Updated on 2022/05/17

写真a

 
MIYASHITA, Tomoyuki
 
Affiliation
Faculty of Science and Engineering, School of Creative Science and Engineering
Job title
Professor
Profile
1992 Nippon Steel Co. Ltd. 2000 Assistant Professor, Waseda Univ. 2001 Dr.Eng, Waseda Univ. 2002 Assistant Professor, Ibaraki Univ. 2005 Associate Professor, Waseda Univ. 2010 Professor, Waseda Univ.

Concurrent Post

  • Faculty of Science and Engineering   Graduate School of Creative Science and Engineering

  • Affiliated organization   Global Education Center

Research Institute

  • 2020
    -
    2022

    理工学術院総合研究所   兼任研究員

  • 2020
    -
    2022

    国際情報通信研究センター   兼任研究員

Education

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    Waseda University   Faculty of Science and Engineering   Department of Mechanical Engineering  

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    Waseda University   Graduate School, Division of Science and Engineering   Major of Mechanical Engineering  

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    Waseda University   Faculty of Science and Engineering   Major of Mechanical  

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    Waseda University   Faculty of Science and Engineering   Major of Mechanical  

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    Waseda University   Graduate School, Division of Science and Engineering   Major of Mechanical Engineering  

Degree

  • 早稲田大学   博士(工学)

Research Experience

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    早稲田大学理工学部機械工学科

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    早稲田大学世紀COE「超高齢社会における人とロボット技術の共生」研究員

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    茨城大学工学部知能システム工学科

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    新日本製鐵株式会社

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    Waseda University   School of Science and Engineering

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    Waseda University

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    早稲田大学世紀COE「超高齢社会における人とロボット技術の共生」研究員

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    茨城大学工学部知能システム工学科

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    Waseda University   School of Science and Engineering

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    新日本製鐵株式会社

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Professional Memberships

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    The American Institute of Aeronautics and Astronautics

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    The American Society of Mechanical Engineers

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    The International Society of Structural and Multidisciplinary Optimization

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    日本応用数理学会

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    情報処理学会

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    日本計算工学会

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    日本機械学会

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Research Areas

  • Mechanics and mechatronics

  • Robotics and intelligent system

  • Medical systems

  • Machine elements and tribology

  • Design engineering

  • Aerospace engineering

  • Mechanics and mechatronics

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Research Interests

  • Inspection

  • Mobility

  • Satellite

  • Robotics

  • Identification

  • Vibration Problem

  • Optimum Design

  • Mathematical Programming

  • Space Structure

  • Aerospace Engineering

  • Strength of Materials

  • Dynamics and Control

  • Design Engineering

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Papers

  • A method to learn high-performing and novel product layouts and its application to vehicle design

    Victor Parque, Tomoyuki Miyashita

    NEUROCOMPUTING   248   41 - 56  2017.07  [Refereed]

     View Summary

    In this paper we aim at tackling the problem of searching for novel and high-performing product designs. Generally speaking, the conventional schemes usually optimize a (multi) objective function on a dynamic model/simulation, then perform a number of representative real-world experiments to validate and test the accuracy of the some product performance metric. However, in a number of scenarios involving complex product configuration, e.g. optimum vehicle design and large-scale spacecraft layout design, the conventional schemes using simulations and experiments are restrictive, inaccurate and expensive.
    In this paper, in order to guide/complement the conventional schemes, we propose a new approach to search for novel and high-performing product designs by optimizing not only a proposed novelty metric, but also a performance function which is learned from historical data. Rigorous computational experiments using more than twenty thousand vehicle models over the last thirty years and a relevant set of well-known gradient-free optimization algorithms shows the feasibility and usefulness to obtain novel and high performing vehicle layouts under tight and relaxed search scenarios.
    The promising results of the proposed method opens new possibilities to build unique and high performing systems in a wider set of design engineering problems. (C) 2017 Elsevier B.V. All rights reserved.

    DOI

  • Simple empirical model for identifying rheological properties of soft biological tissues

    Yo Kobayashi, Mariko Tsukune, Tomoyuki Miyashita, Masakatsu G. Fujie

    PHYSICAL REVIEW E   95 ( 2 )  2017.02  [Refereed]

     View Summary

    Understanding the rheological properties of soft biological tissue is a key issue for mechanical systems used in the health care field. We propose a simple empirical model using fractional dynamics and exponential nonlinearity (FDEN) to identify the rheological properties of soft biological tissue. The model is derived from detailed material measurements using samples isolated from porcine liver. We conducted dynamic viscoelastic and creep tests on liver samples using a plate-plate rheometer. The experimental results indicated that biological tissue has specific properties: (i) power law increase in the storage elastic modulus and the loss elastic modulus of the same slope; (ii) power law compliance (gain) decrease and constant phase delay in the frequency domain; (iii) power law dependence between time and strain relationships in the time domain; and (iv) linear dependence in the low strain range and exponential law dependence in the high strain range between stress-strain relationships. Our simple FDEN model uses only three dependent parameters and represents the specific properties of soft biological tissue.

    DOI

  • A study on the design of deployable cable-panel structure

    Seino, Koujirou, Parque, Victor, Miyashita, Tomoyuki

    4th AIAA Spacecraft Structures Conference, 2017    2017.01

     View Summary

    © 2017, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.Recently, large space structures are being developed. From the point of view of payload capacity and transportation efficiency, large space structures are required to be lightweight and highly efficient in their folding. Cable-panel structures are also expected to satisfy the above conditions mainly due to the omission of frames that hold panels structures. However, the deployment of three-dimensional membranes is difficult to control accurately because of the small stiffness normal to membranes. In this study, we discuss the wire location design in the wire-based deployment of three-dimensional plates. And, through experiments, we evaluate 27 design locations of wires for deployment and compare the deployed shape between the designed dimensions and the measured surface. Then, we confirmed the increment of 2.2 percent in height dimension. Furthermore, we confirmed that our proposed deployment method is feasible, and obtained several design criteria for wire design: First, it is necessary to consider an order of deployment to deploy from the outside surface. Second, the design needs to intersect folds at right angles. Third, extending the length of designs without changing the route shape of the designs leads to higher accuracy of the deployment shape without causing a large increase in the required forces. The multi particle system model was applied to predict the deformation of the structure reasonablly.

  • Expantion and measurement of spiral foldedmembrane by small satellite

    Tomoyuki Miyashita, Hiroshi Yamakawa, Nobuhisa Katsumata, Michihiro C. Natori

    AIAA SciTech Forum - 55th AIAA Aerospace Sciences Meeting    2017

     View Summary

    The small sattelites become popular due to the development of electrical parts and frequent launch opportunities. In this sudy, we will introduce one of our missions on orbit by 1U size small satellite Waseda-SAT3. This satellite have two main missions. One is thermal active control by soft matter and the other is measurement of shpe of membrane expanded from spiral folded shape supported by hinge-less mast. The membrane installed in this satellite has parabolic surface and painted innerside to measure shape by lattice projection method and equips solor cell outside to show effectiveness of spiral folding theory considering thickness effect of the membrane.

    DOI

  • On Succinct Representation of Directed Graphs

    Victor Parque, Tomoyuki Miyashita

    2017 IEEE INTERNATIONAL CONFERENCE ON BIG DATA AND SMART COMPUTING (BIGCOMP)     199 - 205  2017  [Refereed]

     View Summary

    Directed graphs encode meaningful dependencies among objects ubiquitously. This paper introduces new and simple representations for labeled directed graphs with the properties of being succinct (space is information-theoretically optimal); in which we avoid exploiting a-priori knowledge on digraph regularity such as triangularity, separability, planarity, symmetry and sparsity. Our results have direct implications to model directed graphs by using single integer numbers effectively, which is significant to enable canonical (generation of graph instances is unique) and efficient (coding and decoding take polynomial time) encodings for learning and optimization algorithms. To the best of our knowledge, the proposed representations are the first known in the literature.

    DOI

  • Succinct Representation of Directed Graphs

    Parque Victor, Miyashita Tomoyuki

    Proceedings of JSPE Semestrial Meeting   2016 ( 0 ) 577 - 578  2016

     View Summary

    Directed graphs are useful to encode oriented dependencies among entities. We propose a new method that enables the representation of directed graphs via numbers; enabling the succinct, canonical and efficient encoding schemes. We present examples in graph encoding and its applicability to real world networks.

    CiNii

  • Membrane space structure with sterical support of booms and cables

    Torisaka, Ayako, Torisaka, Ayako, Satoh, Yoshitaka, Satoh, Yoshitaka, Akita, Takeshi, Akita, Takeshi, Natori, M. C, Natori, M. C, Yamakawa, Hiroshi, Yamakawa, Hiroshi, Miyashita, Tomoyuki, Miyashita, Tomoyuki

    3rd AIAA Spacecraft Structures Conference    2016.01

     View Summary

    © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.Authors suggested a new structure combined with lightweight membranes and booms using convex tape considering its application as a space structure.. The larger membrane is preferred to get a solar effect from sails and power generation needs. In the past researches, we assumed a square shaped flat structure and studied the use of cables, positions of cables connecting between boom and membrane. In this paper, an additional studies about a steric membrane structure with booms and cables has been carried out to confirm a structural properties. We manufactured experiment model for verifying these properties, and also we confirmed about the same kinds of properties of hexagonal structure.

  • On k-Subset Sum using Enumerative Encoding

    Victor Parque, Tomoyuki Miyashita

    2016 IEEE INTERNATIONAL SYMPOSIUM ON SIGNAL PROCESSING AND INFORMATION TECHNOLOGY (ISSPIT)     81 - 86  2016  [Refereed]

     View Summary

    Being a significant construct in a wide range of combinatorial problems, the k-subset sum problem (k-SSP) computes k-element subsets, out of an n-element set, satisfying a user-defined aggregation value. In this paper, we formulate the k-subset sum problem as a search (optimization) problem over the space of integers associated with combination elements. And by using rigorous computational experiments using the search space over more than 10(14) integer numbers, we show that our approach is effective and efficient: it is feasible to find any combination with a user-defined sum within 10(4) function evaluations by using a gradient-free optimization algorithm. Our scheme opens the door to further advance the understanding of combinatorial problems by improved/tailored gradient-free optimization algorithms based on enumerative encoding. Also, our approach realizes the practical building block for combinatorial problems in planning and operations research using k-SSP concepts.

    DOI

  • Optimization of ZigBee Networks using Bundled Routes

    Parque Victor, Seleem Ibrahim A, Raessa Mohamed S, Miyashita Tomoyuki

    The ... international conference on advanced mechatronics : toward evolutionary fusion of IT and mechatronics : ICAM : abstracts   2015 ( 6 ) 223 - 224  2015.12

     View Summary

    Designing optimal ZigBee networks is key for efficient low-cost communication of multi-agent sensors and mechatronics systems. In this paper, we report a novel approach to optimize ZigBee networks using the optimization of bundled routes. To the best of our knowledge, this is the first approach reported in the literature to find optimal ZigBee network topologies.

    CiNii

  • Optimum Design of Wind Turbine Drivetrain

    Naung Shine Win, Miyashita Tomoyuki

    The ... international conference on advanced mechatronics : toward evolutionary fusion of IT and mechatronics : ICAM : abstracts   2015 ( 6 ) 152 - 153  2015.12

     View Summary

    This article aims to propose a methodology to produce an optimum design of wind turbine drivetrain with the main objectives of minimum vibration, minimum weight and maximum efficiency.

    CiNii

  • Affordable Sensor Fusion for Wireless Control of External Devices

    Raessa Mohamed S, Parque Victor, Miyashita Tomoyuki

    The ... international conference on advanced mechatronics : toward evolutionary fusion of IT and mechatronics : ICAM : abstracts   2015 ( 6 ) 86 - 87  2015.12

     View Summary

    Developing affordable and robust human-machine interfaces is key to improve the quality of life of handicapped and amputee users in developing countries. While most of the available technologies are robust, the cost is inaccessible to large portions of the population with low-income. In this paper, we propose a compact, robust and cost-effective interface for arm pose sensing and control of external devices based on the low-cost accelerometer, gyroscope and Xbee technologies. Experiments using a prototype showed the promising results to detect and classify the robust poses.

    CiNii

  • 2211 A study on optimization of vehicle structure using market data

    HONOBE Kazuhiro, MIYASHITA Tomoyuki

      2015 ( 25 ) "2211 - 1"-"2211-9"  2015.09

     View Summary

    In this research, we proposed a criteria development process treating about 23000 vehicle data which were published on the market from 1982 to 2013 years by Data Envelopment Analysis. DEA is the method for obtaining an evaluation with multidimensional index. However, it is necessary to determine the evaluation model. So we constructed it by Interpretive Structural Modeling. ISM builds a hierarchical structure from paired comparison, and clarifies the relationship between items. As a result, we derived 32 evaluation models from ISM and decided the best model based on the standard deviation to be maximized. This makes it possible to avoid the arbitrariness of the user. In the best model, vehicle data which have lower fuel efficiency obtain higher comprehensive evaluation value. Otherwise, in displacement and price, minimum comprehensive evaluation value is in the middle, vehicle data which has lower and higher evaluation item value obtain higher comprehensive evaluation value. In addition, we optimized the value of each evaluation item for vehicle type and obtained proposition for design for each type, which proposed smaller displacement and shape. From the above, we confirm that DEA is useful for evaluating products and ISM is efficiency for constructing the evaluation model of DEA.

    CiNii

  • Learning the Optimal Product Design Through History

    Victor Parque, Tomoyuki Miyashita

    NEURAL INFORMATION PROCESSING, PT I   9489   382 - 389  2015  [Refereed]

     View Summary

    The search for novel and high-performing product designs is a ubiquitous problem in science and engineering: aided by advances in optimization methods the conventional approaches usually optimize a (multi) objective function using simulations followed by experiments. However, in some scenarios such as vehicle layout design, simulations and experiments are restrictive, inaccurate and expensive. In this paper, we propose an alternative approach to search for novel and high-performing product designs by optimizing not only a proposed novelty metric, but also a performance function learned from historical data. Computational experiments using more than twenty thousand vehicle models over the last thirty years shows the usefulness and promising results for a wider set of design engineering problems.

    DOI

  • Method for Estimating the Temperature Distribution Associated with the Vessel Cooling Effect in Radio Frequency Ablation

    Xiaowei Lu, Hayato Kikuchi, Kazumasa Hirooka, Yosuke Isobe, Hiroki Watanabe, Yo Kobayashi, Tomoyuki Miyashita, Masakatsu G. Fujie

    2015 37TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC)   2015-November   4836 - 4839  2015  [Refereed]

     View Summary

    Recently, radio frequency ablation (RFA) has become one of the most popular thermal treatments for liver cancer. RFA is minimally invasive and effective in inducing tumor coagulation, however, because use the procedure depends on the experience of the physician, consistent accuracy cannot be guaranteed. In particular, when the tumor is close to a large vessel, a suboptimal ablation margin can result in tumor recurrence. To improve the accuracy of RFA treatment, we have developed an RFA supporting system, which was constructed by using finite element method and operated by means of a model-based control method. In this study, we focused on the cooling effect of flow volume inside a large vessel during RFA, and analyzed heat transfer between the large vessel and liver tissue using a model. We derived the heat transfer parameter (the Nusselt number (Nu)) between the large vessel and liver tissue during RFA by using a finite-element method (FEM). When the Nu for FEM analysis had a value of 3, the FEM analysis model was representative of the actual ablation objective, and the maximum error between FEM analysis and the measurement results was within 2.0[degrees C]. Thus, it was suggested that the Nu was effective for FEM analysis regarding heat transfer between a large vessel and tissue. However, according to the differences between the results of FEM analysis and measurements concerning the three livers, the heat transfer volume was determined by the Nu, which is different individually in common with other thermal properties. In conclusion, it is necessary to consider the individual differences in the heat transfer volume parameter for FEM analysis.

    DOI

  • A study on GPU-based Topology Optimization

    KAMEZAKI Hiroki, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2014 ( 27 ) 232 - 234  2014.11

    CiNii

  • A Design of Automobile Structure considering Crashworthiness by Load Transfer Path

    MORISAKI Yohei, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2014 ( 27 ) 191 - 193  2014.11

    CiNii

  • J2410105 Modeling of Heat Generation Value based on Electrical Impedance Frequency Characteristic under Radio-Frequency Ablation

    Yamazaki Nozomu, Kobayashi Yo, Kikuchi Hayato, Lu Xiao Wei, Kusaka Jin, Miyashita Tomoyuki, Fujie Masakatsu G

    Mechanical Engineering Congress, Japan   2014   "J2410105 - 1"-"J2410105-5"  2014.09

     View Summary

    Radio Frequency Ablation (RFA) is one kinds of hyperthermia treatment for cancer. Advantages of RFA are mainly low impact operations and shorter hospital stay. Disadvantage of RFA is difficult to get coagulation information for operator. Therefore, it needs to control ablation energy precisely. Thus, we have been proposed a method control of ablation energy. A feature of RFA, it uses electromagnetic-wave for ablation. RFA is related as not only thermal physics but also electrical physics. And, Heat generation from RF-electrode depends on frequency of electromagnetic-wave frequency. Therefore, in this study, we modeled heat generation based on electric impedance frequency characteristic during RFA. Firstly, it measured electric impedance frequency characteristic of pig liver samples. Secondly, it measured temperature distribution of the samples during RFA. Finally, it modeled electric impedance frequency characteristic of pig liver samples based on equivalent circuit model which was considered about fractional calculus. And, we evaluated a value of electrical impedance. From results, Model value of heat generation was matched with actual measurement value by using a coefficient of electrical impedance.

    CiNii

  • The topology optimization of electronic parts mounted on micro satellite

    Nakamura, H, Miyashita, T

    Engineering Optimization IV - Proceedings of the 4th International Conference on Engineering Optimization, ENGOPT 2014     379 - 384  2014.01

     View Summary

    © 2015 Taylor & Francis Group, London. Printed Circuit Boards (PCBs) are important for operation of actuators to work machines and required upgrading and downsizing. To develop upgrading PCBs needs design based on evaluation criteria. In this study, we verified the availability of GA in pattern design of PCBs by use of the electric power board on WASEDA-SAT2 (small satellite) as a model. As a result, the smaller board by 35% was obtained than the board before optimization.

  • Modeling of Lung's Electrical Impedance using Fractional Calculus for Analysis of heat generation during RF-Ablation

    Nozomu Yamazaki, Yo Kobayashi, Hayato Kikuchi, Yosuke Isobe, XiaoWei Lu, Tomoyuki Miyashita, Masakatsu G. Fujie

    2014 36TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC)     5323 - 5328  2014  [Refereed]

     View Summary

    Recently, Radio Frequency Ablation (RFA) is becoming a popular therapy for various cancers such as liver, breast, or lung cancer. RFA is one kinds of thermal therapy. However, it has been often reported about excessive ablation or non-ablation due to difficult control of ablation energy. In order to solve these difficulties, we have been proposed robotized RF-ablation system for precise cancer treatment. We have been tried to control heat energy by control of electromagnetic-wave frequency.
    In this paper, we reported about relation among electrical impedance of lung, lung's internal air volumes, and heat energy by use of electromagnetic- wave. In case of RFA for lung cancer, heat energy depends on electrical impedance and lung's internal air volumes. Electrical impedance has the dependence of electromagnetic-wave frequency and the dependence of lung's internal air volumes. Therefore, firstly we considered about fractional calculus model between lung's internal air volumes and electrical impedance. Secondly, we measured electric impedance frequency characteristic of lung with change of lung's internal air volumes. The measured and modeled results showed that use of fractional calculus realized high accurate model for electrical impedance of lung. And, from the results of numerical analysis of heat energy, it is supposed that control of electromagnetic-wave frequency has a small effectiveness for lung tissue ablation even if lung includes abundant air.

    DOI

  • 2803 A study on GPU-based FEM analysis of 3-D unsteady heat transfer of sintered metal

    KAMEZAKI Hiroki, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2013 ( 26 ) "2803 - 1"-"2803-3"  2013.11

    CiNii

  • 408 A study on the estimation of passenger's behavior under a train collision

    TAKAHASHI Shuhei, TANAKA Yusuke, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2013 ( 26 ) "408 - 1"-"408-3"  2013.11

    CiNii

  • 3308 A study on the design of scaled impact dummy with optimization methods and similarity rule

    TAKAHASHI Shuhei, MIYASHITA Tomoyuki

      2013 ( 23 ) "3308 - 1"-"3308-10"  2013.10

     View Summary

    Scaled dummy used in the experiment on the estimation of passenger's behavior under a train collision is designed considering a similarity rule. Several tests are applied to evaluate dummy biofidelity according to ISO technicalreport ISO/TR9790. Overall biofidelity of the dummy is 4.62 points out of 10. And it is the third-highest rating "Fair Biofidelity" out of 5 ratings indicating the degree of biofidelity. Next, Finite element is applied conducted to improve thoraxbiofidelity dummy using optimization method, suchas breadth of rib, thickness of soft tissue and Elastic Modulus of soft tissue because response on thoraximpact test is particularly bad. Optimized dummy is developed and thoraximpact test is conducted again. The maximum value of impactor force of optimized dummy is 28.1% better than that of unoptimized one.

    CiNii

  • 3307 A Study on Concept Design Support Using Data Envelopment Analysis

    TAKAHASHI Masafumi, MIYASITA Tomoyuki

      2013 ( 23 ) "3307 - 1"-"3307-10"  2013.10

     View Summary

    In the stage of a conceptual design, designers often stimulate and influence each other, and they must conceive a completely new idea and the outstanding idea. However, as a design problem, it is dependent on a designer's experience and intuition. Furthermore, the suggestion of an idea is sometimes plentifully performed by two or more persons, sharing of mutual knowledge or information for a smooth communication. Therefore, it is necessary to establish the reasonable design method to derive excellent idea, in this study, the new design approach which combined two design methods of an axiomatic design theory and TRIZ is proposed, the validity of a design method is confirmed. The axiomatic design theory clarifies the process in a design TRIZ offers the solution of a design which a designer didn't know. By combining these advantages, we will proposed a new method. The experiment using the proposed methods, technique nothing, TRIZ, the axiomatic design theory, and the TRIZ+ axiomatic design theory. And, it is verified what kind of difference the number of ideas or quality. As a result, TRIZ was able to conceive many ideas, but quality is inferior to other design methods. The axiomatic design theory could conceive the high quality idea, but a number of ideas are inferior to other design methods. Although the TRIZ+ axiomatic design theory had few ideas, the highest quality idea was able to be conceived.

    CiNii

  • 1112 A Study of Design of Shock Absorption Mechanisms Using Compliant Mechanisms

    NAKAMURA Yuta, HATTORI Yuta, MIYASHITA Tomoyuki

      2013 ( 23 ) "1112 - 1"-"1112-10"  2013.10

     View Summary

    In this study, we try to design a shock absorbing structure using the compliant mechanism. To design the shock absorbing structure, it is necessary to consider the plastic deformation. We use the elastic-plastic body to design the compliant mechanism. First, we do topology optimization whose object function is to design the shock absorbing structure and the compliant mechanism. In this topology optimization, we use Evolutionary Structual Optimization. And we investigate the shape and the characteristic while the parameters fluctuation. Secondly, the impact test is done to confirm whether it is functioning as a shock absorbing structure. We test two models and compare the behavior of each model.

    CiNii

  • J164034 Investigation of the Flow Dependence of Heat Transfer Coefficient in Great Vessel for Radio Frequency Ablation

    KIKUCHI Hayato, ISOBE Yosuke, Lu Xiaowei, YAMAZAKI Nozomu, WATANABE Hiroki, KOBAYASHI Yo, MIYASHITA Tomoyuki, FUJIE Masakatsu

    Mechanical Engineering Congress, Japan   2013   "J164034 - 1"-"J164034-4"  2013.09

     View Summary

    Radio frequency ablation (RFA) is one of the minimally invasive and useful treatments for liver cancer. While RFA is popular approach for liver cancer in Japan, RFA has several disadvantages such as ablation temperature is excess or insufficient. Because flow in great vessels absorbs the heat from electrode needle in liver RFA, it is difficult for surgeon to estimate the temperature distribution. In this study, we used the experimental system with porcine great vessels and porcine liver to investigate about the relationship between heat loss and flow volume in great vessels. We calculated the heat transfer coefficient based on Newton's law of cooling under each flow volume in each great vessel, and figured out the relationship between heat transfer coefficient and flow volume. As a result, heat transfer coefficient depends on flow volume in great vessels. And the relationship between heat transfer coefficient and flow volume is linearity. These results suggested that the relationship between flow volume in blood vessel and heat transfer coefficient is linearity, and flow volume in blood vessel causes heat loss in RFA.

    CiNii

  • Pilot Study on Model-Based Temperature Control Method Combined with FEM for Radiofrequency Ablation

    ISOBE Y, L. Xiao Wei, YAMAZAKI N, KOBAYASHI Y, MIYASHITA T, FUJIE M. G

      15 ( 2 ) 136 - 137  2013.08

    CiNii

  • Product design optimization method considering the integrated satisfaction level

    Masataka Yoshimura, Masaki Sato, Tomoyuki Miyashita, Hiroshi Yamakawa

    Control and Intelligent Systems   41 ( 3 ) 117 - 126  2013

     View Summary

    We propose a product design optimization method that maximizes the integrated satisfaction level for evaluative factors. Product designs include many evaluative factors that have complex interrelationships. To cope with such circumstances, we construct strategies and a practical method to obtain optimum design solutions. First, the evaluative items for the product are listed and each item is decomposed into evaluative factors. Next, to express designers' or potential customers' levels of satisfaction for the characteristic values of each evaluative factor, we define satisfaction functions that incorporate the relationship between characteristic values and satisfaction levels. Weighting coefficients for the evaluative factors are then obtained by the pair comparison method. Finally, an integrated satisfaction level is formulated by summing the characteristic values with their weighting coefficients over the entire set of evaluative factors. The integrated satisfaction level of the objective function is maximized, and optimum design solutions with maximum satisfaction levels are then obtained. If necessary, these solutions can be modified and improved by re-examining and adjusting the satisfaction functions and weighting coefficients. Furthermore, the proposed method can be used to find schemes that improve the integrated satisfaction level. The utility of the proposed method is demonstrated using a passenger train coach design.

    DOI

  • Development of a coagulation area presenting system in liver radio frequency ablation (Modeling for temperature-dependence of viscoelasticity in liver tissue)

    Xiaowei Lu, Mariko Tsukune, Hiroki Watanabe, Yo Kobayashi, Tomoyuki Miyashita, Masakatsu G. Fujie

    Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C   79 ( 807 ) 4381 - 4388  2013

     View Summary

    Recently radio frequency ablation (RFA) has been increasingly important in treating liver cancers. RFA is ordinarily conducted using elastographic imaging to monitor the ablation procedure and the temperature of the electrode needle is displayed on the radiofrequency generator. However, the coagulation boundary of liver tissue in RFA is unclear and unconfident. This can lead to both excessive and insufficient RFA thereby diminishing the advantages of the procedure. In the present study, we developed a method for determining the coagulation boundary of liver tissue in liver RFA. To investigate this boundary we used the mechanical characteristics of biochemical components as an indicator of coagulation to produce a relational model for viscoelasticity and temperature. This paper presents the data acquisition procedures for the viscoelasticity characteristics and the results of relationship model of viscoelasticity's temperature dependence. We employed a rheometer to measure the viscoelastic characteristics of porcine liver tissue. To determine relationship model between temperature and viscoelasticity, we used a least-square method and the minimum root mean square error was calculated to optimize the model functional relations. The functional relation between temperature and viscoelasticity was divided into linear and non-linear in different temperature regions. The boundary between linear and non-linear functional relation was 58.0°C. © 2013 The Japan Society of Mechanical Engineers.

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  • Real-time temperature control system based on the finite element method for liver radiofrequency ablation: Effect of the time interval on control

    Yosuke Isobe, Hiroki Watanabe, Nozomu Yamazaki, Xiaowei Lu, Yo Kobayashi, Tomoyuki Miyashita, Makoto Hashizume, Masakatsu G. Fujie

    Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS     392 - 396  2013

     View Summary

    Radiofrequency (RF) ablation is increasingly being used to treat liver cancer because it is minimally invasive. However, it is difficult for operators to control the size of the coagulation zones precisely, because no method has been established to form an adequate and suitable ablation area. To overcome this limitation, we propose a new system that can control the coagulation zone size. The system operates as follows: 1) the liver temperature is estimated using a temperature-distribution simulator to reduce invasiveness
    2) the output power of the RF generator is controlled automatically according to the liver temperature. To use this system in real time, both the time taken to calculate the temperature in the simulation and the control accuracy are important. We therefore investigated the relationship between the time interval required to change the output voltage and temperature control stability in RF ablation. The results revealed that the proposed method can control the temperature at a point away from the electrode needle to obtain the desired ablation size. It was also shown to be necessary to reduce the time interval when small tumors are cauterized to avoid excessive treatment. In contrast, such high frequency feedback control is not required when large tumors are cauterized. © 2013 IEEE.

    DOI PubMed

  • The relation between temperature distribution for lung RFA and electromagnetic wave frequency dependence of electrical conductivity with changing a lung's internal air volumes

    Nozomu Yamazaki, Hiroki Watanabe, XiaoWei Lu, Yosuke Isobe, Yo Kobayashi, Tomoyuki Miyashita, Masakatsu G. Fujie

    2013 35TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC)     386 - 391  2013  [Refereed]

     View Summary

    Radio frequency ablation (RFA) for lung cancer has increasingly been used over the past few years because it is a minimally invasive treatment. As a feature of RFA for lung cancer, lung contains air during operation. Air is low thermal and electrical conductivity. Therefore, RFA for this cancer has the advantage that only the cancer is coagulated, and it is difficult for operators to control the precise formation of coagulation lesion. In order to overcome this limitation, we previously proposed a model-based robotic ablation system using finite element method. Creating an accurate thermo physical model and constructing thermal control method were a challenging problem because the thermal properties of the organ are complex. In this study, we measured electromagnetic wave frequency dependence of lung's electrical conductivity that was based on lung's internal air volumes dependence with in vitro experiment. In addition, we validated the electromagnetic wave frequency dependence of lung's electrical conductivity using temperature distribution simulator. From the results of this study, it is confirmed that the electromagnetic wave frequency dependence of lung's electrical conductivity effects on heat generation of RFA.

    DOI

  • Boundary condition generating large strain on breast tumor for nonlinear elasticity estimation

    Mariko Tsukune, Maya Hatano, Yo Kobayashi, Tomoyuki Miyashita, M. G. Fujie

    Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS     4863 - 4866  2013

     View Summary

    We describe a robotic palpation system that determines whether a breast tumor is benign or malignant by measuring its nonlinear elasticity. Two indenters compress the breast from different directions to generate sufficient strain on the inner tumor, which simply represents clinical dynamic testing. The nonlinear elasticity of the inner tumor is estimated by correcting the reaction force data of the surrounding soft tissue. Here, we present the basic concept of our study and simulation results considering geometric conditions of the indenters using a finite element breast model. Indenters with variable width are applied to the breast at several contact positions in a simulation for comparison. Our results indicate that when the spring stiffness between the contact position of one indenter and the center of the tumor equals the spring stiffness between the contact position of the other indenter and the center of the tumor, a larger contact area (i.e., larger spring stiffness) provides larger strain acting on the inner tumor. © 2013 IEEE.

    DOI PubMed

  • Derivation of the relationship between the rate of temperature rise and viscoelasticity for constructing a coagulation model for liver radio frequency ablation

    Xiaowei Lu, Hiraki Watanabe, Yosuke Isobe, Nozomu Yamazaki, Yo Kobayashi, Tomoyuki Miyashita, Masakatsu G. Fujie

    Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS     382 - 385  2013

     View Summary

    Radio frequency ablation (RFA) is usually conducted using ultrasound (US) imaging to monitor the insertion procedure and the coagulation extent of liver tissue which is contiguous to the RFA electrode. However, when RFA surgery is started, the US image becomes unclear because of water vapor. This disadvantage of RFA can lead to excessive and insufficient RFA thereby diminishing the advantages of the procedure. In the present study, we proposed a simulation system which shows the progress status of coagulation for liver RFA. To derive the coagulation characteristics in liver RFA, we used the viscoelasticity of liver tissue as the coagulation indicator to investigate coagulation development for liver RFA. This paper shows the acquisition procedures for analyzing the relationship between the rate of temperature and viscoelasticity. We measured the complex modulus of porcine liver tissue under different rate of temperature in RFA by controlling the output power. We showed that the viscoelasticity of liver tissue depended on temperature previous temperature increase above 60°C. This result indicates that in RFA, controlling the output power is important to completely coagulate the tumor. © 2013 IEEE.

    DOI PubMed

  • Development of a coagulation area presenting system in liver radio frequency ablation (Modeling for temperature-dependence of viscoelasticity in liver tissue)

    Xiaowei Lu, Mariko Tsukune, Hiroki Watanabe, Yo Kobayashi, Tomoyuki Miyashita, Masakatsu G. Fujie

    Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C   79 ( 807 ) 4381 - 4388  2013

     View Summary

    Recently radio frequency ablation (RFA) has been increasingly important in treating liver cancers. RFA is ordinarily conducted using elastographic imaging to monitor the ablation procedure and the temperature of the electrode needle is displayed on the radiofrequency generator. However, the coagulation boundary of liver tissue in RFA is unclear and unconfident. This can lead to both excessive and insufficient RFA thereby diminishing the advantages of the procedure. In the present study, we developed a method for determining the coagulation boundary of liver tissue in liver RFA. To investigate this boundary we used the mechanical characteristics of biochemical components as an indicator of coagulation to produce a relational model for viscoelasticity and temperature. This paper presents the data acquisition procedures for the viscoelasticity characteristics and the results of relationship model of viscoelasticity's temperature dependence. We employed a rheometer to measure the viscoelastic characteristics of porcine liver tissue. To determine relationship model between temperature and viscoelasticity, we used a least-square method and the minimum root mean square error was calculated to optimize the model functional relations. The functional relation between temperature and viscoelasticity was divided into linear and non-linear in different temperature regions. The boundary between linear and non-linear functional relation was 58.0°C. © 2013 The Japan Society of Mechanical Engineers.

    DOI

  • 2208 A study on optimization of Shock absorbing structures as Compliant Mechanisms

    HATTORI Yuta, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2012 ( 25 ) 154 - 156  2012.10

    CiNii

  • Investigation into the indicator of coagulation for liver radio frequency ablation

    LU Xiaowei, TSUKUNE Mariko, ISOBE Yosuke, YAMAZAKI Nozomu, WATANABE Hiroki, KOBAYASHI Yo, KAKIMOTOD Takashi, CHIBA Toshio, MIYASHITA Tomoyuki, FUJIE Masakatsu G

      14 ( 3 ) 422 - 423  2012.10

    CiNii

  • Developing a method to identify the elastic modulus of soft tissue based on comparison analysis of FEA and ultrasound image

    HOSHI T, TSUKUNE M, KOBAYASHI Y, MIYASHITA T, FUJIE M. G

      14 ( 3 ) 282 - 283  2012.10

    CiNii

  • Development of a temperature distribution simulator for lung RFA based on lung's internal air dependence of thermal and electrical conductivity

    YAMAZAKI N, WATANABE H, ISOBE Y, WEI L. Xiao, KOBAYASHI Y, MIYASHITA T, FUJIE M. G

      14 ( 3 ) 278 - 279  2012.10

    CiNii

  • Development of Breast Cancer Diagnostic Support System Based on the Nonlinear Elasticity : Deformation Analysis of breast during palpation by robotic manipulator

    TSUKUNE M, KOBAYASHI Y, MIYASHITA T, SHIRAISHI Y, YAMBE T, HASHIZUME M, FUJIE M. G

      14 ( 3 ) 206 - 207  2012.10

    CiNii

  • J165034 Development of Robotic Palpation System to Measure the Nonlinear Elasticity for Breast Cancer Diagnosis Support : Consideration of Compression Method Using Two Indenters by Finite Element Analysis

    TSUKUNE Mariko, KOBAYASHI Yo, MIYASHITA Tomoyuki, SHIRAISHI Yasuyuki, YAMBE Tomoyuki, HASHIZUME Makoto, FUJIE Masakatsu

    Mechanical Engineering Congress, Japan   2012   "J165034 - 1"-"J165034-3"  2012.09

     View Summary

    A disadvantage of nonlinear elastography techniques for breast tumor diagnosis is that the tumor does not strain sufficiently to observe nonlinear elasticity We propose a robotic palpation system with two indenters to evaluate the nonlinear elasticity properties of tissues The objective of the present study was to consider a compression method in terms of the position of indenters and the section area of indenters to generate large strain in tumors by finite element analysis As a result, it was found that the following compression conditions made tumor deformable First condition is that the default position of indenter is located near the tumor Second condition is that the section area of indenters is enlarged if the default position of indenter is located near the tumor, and the section area of indenters is made smaller if the default position of indenter is distance from the tumor

    CiNii

  • Validation of accuracy of liver model with temperature-dependent thermal conductivity by comparing the simulation and in vitro RF ablation experiment.

    Watanabe Hiroki, Yamazaki Nozomu, Isobe Yosuke, Lu XiaoWei, Kobayashi Yo, Miyashita Tomoyuki, Ohdaira Takeshi, Hashizume Makoto, Fujie Masakatsu G

    Validation of accuracy of liver model with temperature-dependent thermal conductivity by comparing the simulation and in vitro RF ablation experiment.   2012  2012.09  [Refereed]

     View Summary

    :Radiofrequency (RF) ablation is increasingly used to treat cancer because it is minimally invasive. However, it is difficult for operators to control precisely the formation of coagulation zones because of the inadequacies of imaging modalities. To overcome this limitation, we previously proposed a model-based robotic ablation system that can create the required size and shape of coagulation zone based on the dimensions of the tumor. At the heart of such a robotic system is a precise temperature distribution simulator for RF ablation. In this article, we evaluated the simulation accuracy of two numerical simulation liver models, one using a constant thermal conductivity value and the other using temperature-dependent thermal conductivity values, compared with temperatures obtained using in vitro experiments. The liver model that reflected the temperature dependence of thermal conductivity did not result in a large increase of simulation accuracy compared with the temperature-independent model in the temperature range achieved during clinical RF ablation.

    DOI

  • Development of a temperature distribution simulator for lung RFA based on air dependence of thermal and electrical properties.

    Yamazaki Nozomu, Watanabe Hiroki, Lu XiaoWei, Isobe Yosuke, Kobayashi Yo, Miyashita Tomoyuki, Fujie Masakatsu G

    Development of a temperature distribution simulator for lung RFA based on air dependence of thermal and electrical properties.   2012  2012.09  [Refereed]

     View Summary

    :Radio frequency ablation (RFA) for lung cancer has increasingly been used over the past few years, because it is a minimally invasive treatment. As a feature of RFA for lung cancer, lung contains air. Air is low thermal and electrical conductivity. Therefore, RFA for this cancer has the advantage that only the cancer is coagulated, because the heated area is confined to the immediate vicinity of the heating point. However, it is difficult for operators to control the precise formation of coagulation zones due to inadequate imaging modalities. We propose a method using finite element method to analyze the temperature distribution of the organ in order to overcome the current deficiencies. Creating an accurate thermal physical model was a challenging problem because of the complexities of the thermal properties of the organ. In this study, we developed a temperature distribution simulator for lung RFA using thermal and electrical properties that were based on the lung's internal air dependence. In addition, we validated the constructed simulator in an in vitro study, and the lung's internal heat transfer during RFA was validated quantitatively.

    DOI

  • A study on estimation of the deformation behavior in the collapse process of lung.

    Katsuyama Yusuke, Yamazaki Nozomu, Kobayashi Yo, Hoshi Takeharu, Miyashita Tomoyuki

    A study on estimation of the deformation behavior in the collapse process of lung.   2012  2012.09  [Refereed]

     View Summary

    :In this paper, finite element methodology was applied to predict the deformation of tissue during lung collapse using pre-operative information. Accurate prediction of lung collapse deformation prior to surgical intervention can provide valuable diagnostic information to clinical staff, allowing a better understanding of the movement of the target segment. This paper describe the methodology to derive the deformed shape of finite element model that satisfy the equilibrium condition using 3-D model developed from the image measured by a multi-slice CT imaging device. The movement of the target segment can be predicted by the finite element model. Previous research studies applied the distributed load on the surface of the lung structure as loading conditions. Here we have suggested a method that considers the deformation of alveoli contraction and elongation while breathing. Specifically, by introducing the governing equations of a reduction in volume strain into the governing equations of the finite element method, lung structure is analyzed. Lung deformation obtained from the analysis was compared with experimental results and compared with the proposed method. The proposed method showed an improvement of deformation-prediction accuracy as 0.58%. We confirmed the qualitative similarities between the deformation of the analysis and the experiment, thus demonstrating the effectiveness of the proposed method.

    DOI

  • A method for deriving the coagulation boundary of liver tissue using a relational model of viscoelasticity and temperature in radio frequency ablation.

    Lu Xiaowei, Tsukune Mariko, Watanabe Hiroki, Yamazaki Nozomu, Isobe Yosuke, Kobayashi Yo, Miyashita Tomoyuki, Fujie Masakatsu G

    A method for deriving the coagulation boundary of liver tissue using a relational model of viscoelasticity and temperature in radio frequency ablation.   2012  2012.09  [Refereed]

     View Summary

    :Recently radiofrequency (RF) ablation has become increasingly important in treating liver cancers. RF ablation is ordinarily conducted using elastographic imaging to monitor the ablation procedure and the temperature of the electrode needle is displayed on the RF generator. However, the coagulation boundary of liver tissue in RF ablation is unclear and unconfident. This can lead to both excessive and insufficient RF ablation thereby diminishing the advantages of the procedure. In the present study, we developed a method for determining the coagulation boundary of liver tissue in RF ablation. To investigate this boundary we used the mechanical characteristics of biochemical components as an indicator of coagulation to produce a relational model for viscoelasticity and temperature. This paper presents the data acquisition procedures for the viscoelasticity characteristics and the analytical method used for the coagulation model. We employed a rheometer to measure the viscoelastic characteristics of liver tissue. To determine the model functional relationship between viscoelasticity and temperature, we used a least-square method and the minimum root mean square error was calculated to optimize the model functional relations. The functional relation between temperature and viscoelasticity was linear and non-linear in different temperature regions. The boundary between linear and non-linear functional relation was 58.0°C.

    DOI

  • 3407 Experimental study of seating type and passenger behavior in railway vehicle collision

    MATSUDA Atsushi, MIYASHITA Tomoyuki

      2012 ( 22 ) "3407 - 1"-"3407-10"  2012.09

     View Summary

    When major train collisions occur, train structure deforms to reduce the impact effect. However, some passengers are injured in spite of the shock absorption of the structure. Therefore, it is necessary to design train structure to reduce injuries of passengers when accidents occur. In this study, we proposed the design improvements strategies to reduce injuries of the passengers caused by train collisions. We experimented with scale-down models of passengers and vehicles. To evaluate injury levels, we used HIC36 as a standard for head injuries. As a result of these experiments, HIC36 is influenced by seating position and type. We proposed three train structures to reduce injuries of passengers. These are that of using convertible seats, seating passengers with their backs to the front of the train and seating passengers in the rear of the vehicle.

    CiNii

  • 2309 Study of Designing Shock Absorption Mechanisms Using Compliant Mechanisms

    OKADA Kenta, MIYASHITA Tomoyuki

      2012 ( 22 ) "2309 - 1"-"2309-10"  2012.09

     View Summary

    In this study, to design a shock absorbing structure using the compliant mechanism. To be applied to the shock absorbing structure is necessary to consider the plastic deformation. However, in previous studies such research has not been done. In the present study to design a compliant mechanism targets the elasto-plastic body. And this mechanism is applied to impact-absorbing structure. First we use topology optimization whose object function is to design shock absorbing structure and compliant mechanism. And we can design model which has compliant mechanism and shock absorbing function. Secondly impact test is performed using this mechanism. We create a model for comparison for this test. We compare the behavior of each model and discuss about it.

    CiNii

  • 2208 A study on minimization of weight for satellite considering component location

    MIZUMACHI Seiya, MIYASHITA Tomoyuki

      2012 ( 22 ) "2208 - 1"-"2208-10"  2012.09

     View Summary

    Recently the development of the nano satellite becomes active. In general, nano satellites are expected to be developed faster and cheaper than the large satellites. The launching cost of the piggyback satellite is reasonable, and then a cost of a piggyback satellite is often decided by weight. Therefore it is important to reduce the weight of satellite for cost. We have to design of satellite structure considering the severe mechanical environment of launching. The natural frequency of the satellite should be higher than the value decided by the rocket and the satellite should withstand the loads during launch. In addition, harnesses are also important component when we design satellites. In this paper, we will propose the design of the satellite whose dimension is 400 millimeters cube. The satellite supposed to be launched by H-2A rocket and we focused on the trade-off design between minimization of mass and maximization of natural frequency under the maximum stress condition for optimizing the satellite structures.

    CiNii

  • 2A2-S09 Investigation into mechanism of electrode needle which allows generating asymmetric ablation shape in RFA(Surgical Robotics and Mechatronics (1))

    ISOBE Yosuke, YAMAZAKI Nozomu, WATANABE Hiroki, KOBAYASHI Yo, MIYASHITA Tomoyuki, OHDAIRA Takeshi, HASHIZUME Makoto, FUJIE Masakatsu G

      2012   "2A2 - S09(1)"-"2A2-S09(3)"  2012.05

     View Summary

    RFA is a treatment modality for cancer that is becoming accepted because of its less-invasiveness and high-curability. Controlling the shape of ablation area increases curative effect. Therefore we propose the mechanism of electrode needle that RF current flow between two secondary electrode needles. We examined the parameters required to obtain a trapezoidal ablation area surrounded by two electrode needles. The result of simulation, it was suggested that the relation of length and thickness of two needles affect ablation. In addition, we performed ablation experiments using agar phantoms. We evaluated the ablation shape of simulation and experiment as three-dimensional cube set. Then, we confirmed that result of simulation and experiments were in agreement.

    CiNii

  • Product design optimization method considering the integrated satisfaction level

    Masataka Yoshimura, Masaki Satou, Tomoyuki Miyashita, Hiroshi Yamakawa

    Proceedings of the IASTED International Conference on Engineering and Applied Science, EAS 2012     303 - 310  2012

     View Summary

    We propose a product design optimization method that maximizes the integrated satisfaction level for evaluative factors. Product designs include many evaluative factors that have complex interrelationships. To cope with such circumstances, we construct strategies and a practical method to obtain optimum design solutions. First, the evaluative items for the product are listed and each item is decomposed into evaluative factors. Next, to express designers' or potential customers' levels of satisfaction for the characteristic values of each evaluative factor, we define satisfaction functions that incorporate the relationship between characteristic values and satisfaction levels. Weighting coefficients for the evaluative factors are then obtained by the pair comparison method. Finally, an integrated satisfaction level is formulated by summing the characteristic values with their weighting coefficients over the entire set of evaluative factors. The integrated satisfaction level of the objective function is maximized, and optimum design solutions with maximum satisfaction levels are then obtained. If necessary, these solutions can be modified and improved by re-examining and adjusting the satisfaction functions and weighting coefficients. Furthermore, the proposed method can be used to find schemes that improve the integrated satisfaction level. The utility of the proposed method is demonstrated using a passenger train coach design.

    DOI

  • Pilot study for Ablation lesion of lung RFA with temperature distribution simulator based on lung internal air dependence

    YAMAZAKI N, WATANABE H, SEKI M, KOBAYASHI Y, MIYASHITA T, FUJIE M. G

      13 ( 3 ) 292 - 293  2011.11

    CiNii

  • Estimation of Intraoperative Blood Flow during Liver RF Ablation Using a Finite Element Method-based Biomechanical Simulation

    WATANABE H, YAMAZAKI N, KOBAYASHI Y, MIYASHITA T, OHDAIRA T, HASHIZUME M, FUJIE M. G

      13 ( 3 ) 286 - 287  2011.11

    CiNii

  • 2309 A study on estimation of the deformation behavior in the collapse process of lung

    KATSUYAMA Yusuke, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2011 ( 24 ) 648 - 650  2011.10

    CiNii

  • 2002 A study on GPU-based FEM analysis of medical images

    KOBAYASHI Yuta, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2011 ( 24 ) 589 - 591  2011.10

    CiNii

  • 3202 A study on minimization of weight for satellite considering component location

    MIZUMACH Seiya, MIYASHITA Tomoyuki

      2011 ( 21 ) 537 - 542  2011.10

     View Summary

    Recently the development of the nano satellite becomes active. In general, nano satellites are expected to be developed faster and cheaper than the large satellites. The launching cost of the piggyback satellite is reasonable, and then a cost of a piggyback satellite is often decided by weight. Therefore it is important to reduce the weight of satellite for cost. We have to design of satellite structure considering the severe mechanical environment of launching. The natural frequency of the satellite should be higher than the value decided by the rocket and the satellite should withstand the loads during launch. In this paper, we will propose the design of the satellite whose dimension is 400 millimeters cube. The satellite supposed to be launched by H-II A rocket and we focused on the trade-off design between minimization of mass and maximization of natural frequency under the maximum stress condition for optimizing the satellite structures.

    CiNii

  • 2403 An experimental study on the estimation of passenger's behavior in under a train collision

    TANAKA Yusuke, MIYASHITA Tomoyuki

      2011 ( 21 ) 376 - 381  2011.10

     View Summary

    An experiment on the estimation of a large number of passenger's behavior in under a train collision is studied using small train model. Here, we treated the position of passenger paying attention to a seat for seven persons. As a result of the experiment, passenger's head injury is influenced by seating position or coefficient of static friction of floor material. We discussed relation of between seating position or coefficient of static friction of floor material and passenger's head injury, and proposed four ideas reducing damage of passengers.

    CiNii

  • 2101 A Study on Conceptual Design Method Applying Data Envelopment Analysis and TRIZ

    SATO Masaki, HANADA Ryu, MIYASHITA Tomoyuki

      2011 ( 21 ) 129 - 134  2011.10

     View Summary

    In conceptual design phase, According paying attention to specific design objectives, designers sometimes avoid to get various ideas about new product. On the other hand, using brainstorming allows to get various ideas, but it causes a problem to obtain a lot of unavailable ideas together. In this study, to support generating various and effective ideas in conceptual design, we propose a conceptual design support method applying Data Envelopment Analysis and TRIZ. We proposed the method using several evaluation values to fill the gap of pareto frontier and creating hierarchy graphs. In this study, we propose the method using TRIZ at the Brain Storming stage in addition to the our proposed method. Various information is given to the designer from hierarchy relation graphically and TRIZ when they conceive new ideas. We verified which technique is effective to obtain new ideas with high evaluation by comparing these two methods. The result shows that the proposed method using TRIZ is more efficient than the other way not using TRIZ.

    CiNii

  • Estimation of intraoperative blood flow during liver RF ablation using a finite element method-based biomechanical simulation.

    Watanabe Hiroki, Yamazaki Nozomu, Kobayashi Yo, Miyashita Tomoyuki, Ohdaira Takeshi, Hashizume Makoto, Fujie Masakatsu G

    Estimation of intraoperative blood flow during liver RF ablation using a finite element method-based biomechanical simulation.   2011  2011.09  [Refereed]

     View Summary

    :Radiofrequency ablation is increasingly being used for liver cancer because it is a minimally invasive treatment method. However, it is difficult for the operators to precisely control the formation of coagulation zones because of the cooling effect of capillary vessels. To overcome this limitation, we have proposed a model-based robotic ablation system using a real-time numerical simulation to analyze temperature distributions in the target organ. This robot can determine the adequate amount of electric power supplied to the organ based on real-time temperature information reflecting the cooling effect provided by the simulator. The objective of this study was to develop a method to estimate the intraoperative rate of blood flow in the target organ to determine temperature distribution. In this paper, we propose a simulation-based method to estimate the rate of blood flow. We also performed an in vitro study to validate the proposed method by estimating the rate of blood flow in a hog liver. The experimental results revealed that the proposed method can be used to estimate the rate of blood flow in an organ.

    DOI

  • Evaluation and comparison of the nonlinear elastic properties of the soft tissues of the breast.

    Tsukune Mariko, Kobayashi Yo, Hoshi Takeharu, Miyashita Tomoyuki, Fujie Masakatsu G

    Evaluation and comparison of the nonlinear elastic properties of the soft tissues of the breast.   2011  2011.09  [Refereed]

     View Summary

    :As the number of breast cancer patients increases, there is an increasing need for accurate non-invasive methods for the diagnosis of breast cancer. It is possible that the nonlinear elastic properties of soft tissues of the breast can be used as a basis for diagnostic methods. Therefore, we have proposed a robotic palpation system for diagnosis based on the nonlinear elastic properties of tissue. Here, we measured the nonlinear elastic properties of soft tissues of the breast using creep tests and three parameters of the nonlinear elastic model were acquired. Two of these parameters are significantly different among soft tissues of the breast and that the magnitude of these parameters was determined by the tissue structure. These parameters could be used to differentiate between tissue types and aid in the diagnosis of breast cancer.

    DOI

  • Palpation nonlinear reaction force analysis for characterization of breast tissues.

    Kobayashi Yo, Tsukune Mariko, Hoshi Takeharu, Miyashita Tomoyuki, Shiraishi Yasuyuki, Yambe Tomoyuki, Fujie Masakatsu G

    Palpation nonlinear reaction force analysis for characterization of breast tissues.   2011  2011.09  [Refereed]

     View Summary

    :This paper addresses a diagnostic palpation system based on the measurement of nonlinear elasticity. An indentation probe is used to press against breast tissue. Then, the measured reaction force is used to estimate the parameters of nonlinear elasticity, which enables the identification of tissue type, such as fat, muscle, mammary gland or tumor. Here, we present the basic concept of our study and preliminary experimental and simulation results from pilot studies. More specifically, we measured the nonlinear response of reaction force using the breast of a goat. In addition, we also simulated the reaction force using nonlinear biomechanical simulation with several tissue types. Large differences in reaction force occur only in the nonlinear range in both experimental and simulation situations. Our results confirmed the feasibility of our concept.

    DOI

  • Modeling the internal pressure dependence of thermal conductivity and in vitro temperature measurement for lung RFA.

    Yamazaki Nozomu, Watanabe Hiroki, Seki Masatoshi, Hoshi Takeharu, Kobayashi Yo, Miyashita Tomoyuki, Fujie Masakatsu G

    Modeling the internal pressure dependence of thermal conductivity and in vitro temperature measurement for lung RFA.   2011  2011.09  [Refereed]

     View Summary

    :Radio frequency ablation (RFA) for lung cancer has increasingly been used over the past few years because RFA is minimally invasive treatment for patients. As a feature of RFA for the lung cancer, lung has the air having low thermal conductivity. Therefore, RFA for lung has the advantage that only the tumor is coagulated because heating area is confined to the immediate vicinity of the heating point. However, it is difficult for operators to control the precise formation of coagulation zones due to inadequate imaging modalities. We propose a method using numerical simulation to analyze the temperature distribution of the organ in order to overcome the current deficiencies. Creating an accurate thermophysical model was a challenging problem because of the complexities of the thermophysical properties of the organ. In this work, as the processes in the development of ablation simulator, measurement of the pressure dependence of lung thermal conductivity and in vitro estimation of the temperature distribution during RFA is presented.

    DOI

  • Development and evaluation of an identification method for the biomechanical parameters using robotic force measurements, medical images, and FEA.

    Hoshi Takeharu, Tsukune Mariko, Kobayashi Yo, Miyashita Tomoyuki, Fujie Masakatsu G

    Development and evaluation of an identification method for the biomechanical parameters using robotic force measurements, medical images, and FEA.   2011  2011.09  [Refereed]

     View Summary

    :This paper presents a new identification method for the biomechanical parameters of human tissues for the purpose of improving the accuracy of dynamic organ simulation. We describe the formulation of the method, and also design a robotic system to implement the method using a robotic probe, a medical imaging device, and a numerical simulator for the finite element analysis (FEA). We carried out an experiment using an experimental system and a tissue phantom to verify the effectiveness of the method. The results of this experiment show that the Young's modulus of the tissue phantom can be estimated with the experimental system. We also compared the estimated values of the Young's moduli with the measured values from a rheometer. These results confirm that the identification method and the system design, proposed and developed in this work, are effective for accurately simulating organ behavior.

    DOI

  • Investigation of lung lethargy deformation using finite element method

    Zamani, M. K, Yamanaka, M, Miyashita, T, Ramli, R

    IFMBE Proceedings   35 IFMBE   170 - 174  2011.07  [Refereed]

     View Summary

    Lung cancer has become one of most killing disease in 20th century. There are various external and internal causes identified by experts to be the causes of this disease. Various type of treatments have been developed taking account on the stage and condition of cancer itself, such as Radiation Therapy, Chemotherapy and Surgery. In this paper, a method called Thoracoscopy is focused for improvement by investigating a possibility of using finite element method (FEM) to predict deformation and movement of tumor during lung lethargy process as a preparation stage for this surgery method to be deployed. Thoracoscopy is suitable for stage-I cancer, as it will only create a small incisions on the skin and has high possibility to cure by removing the tumor. This paper used a commercial FEM tool to model lung in 3-dimension and by using tested data of material properties, a simulated result of lung lethargy process was compared with experimental data. Results revealed a few promising points to further develop this virtual capability and use it to predict deformation prior the surgery. © 2011 Springer-Verlag.

    DOI

  • 2P1-C08 Measuring the nonlinear elastic properties of breast tissue components and comparison of measurement results(Medical Robotics and Mechatronics)

    TSUKUNE Mariko, KOBAYASHI Yo, HOSHI Takeharu, MIYASHITA Tomoyuki, FUJIE Masakatsu G

      2011   "2P1 - C08(1)"-"2P1-C08(4)"  2011.05

     View Summary

    As the number of breast cancer patients increases, non- invasive and accuracy diagnosis of breast cancer is required. It is expected that there is diagnostic potential in examining the nonlinear elastic properties of soft tissues. The measurement method of the nonlinear elasticity of tumor in breast is needed. Therefore, we propose the robotic palpation system for diagnosis based the nonlinear elasticity. Here, we report the measurement of the nonlinear elastic properties of breast tissue components. The nonlinear elastic properties of breast tissue were investigated with a creep test. The three parameters of the nonlinear elastic model were acquired. In conclusion, two of these parameters are significantly different among the components. There was indicated that the magnitude of parameter is determined by tissue structure. There was suggested that the difference in parameter distribution causes the difference in dynamic response of breast tissue.

    CiNii

  • Quantitative palpation to identify the material parameters of tissues using reactive force measurement and finite element simulation

    Hoshi, Takeharu, Kobayashi, Yo, Miyashita, Tomoyuki, Fujie, Masakatsu G

    IEEE/RSJ 2010 International Conference on Intelligent Robots and Systems, IROS 2010 - Conference Proceedings     2822 - 2828  2010.12  [Refereed]

     View Summary

    In this paper we present a new robotic palpation method to perform quantitative measurement of the material parameters of human tissues, for use in medical applications. The proposed method is achieved by the use of a system that integrates a robotic component and a numerical simulation component. The robotic component is used to measure the contact force and displacement at each point on the human body contacted by a robotic probe. The numerical simulation component identifies the material parameters using the proposed method, where two data sources are used, namely, (1) the measured data from the robotic part, and (2) simulated deformation data obtained by the finite element method. In order to validate the proposed system, we report initial results from several phantom tissue experiments, which demonstrate the ability of the system to quantitatively determine the elastic moduli of tissues. We also discuss several potential challenges in the future of the proposed system. ©2010 IEEE.

    DOI

  • Measurement of the RF-needle neighborhood temperature distribution during Radio Frequency Ablation for Lung

    YAMAZAKI N, WATANABE H, SEKI M, KOBAYASHI Y, MIYASITA T, FUJIE M. G

      12 ( 3 ) 302 - 303  2010.11

    CiNii

  • 1501 A research on watch device for packing structure and contents acting impact force

    MIZUNO Tomomasa, MIYASHITA Tomoyuki

      2010 ( 20 ) "1501 - 1"-"1501-6"  2010.10

     View Summary

    The corrugated cardboard is widely used for packing in the transportation. Therefore, the technology that minimizes various transportation accidents is necessary. Especially, the accidents by the impact occupies the more than the half of the accidents. There are many researches that evaluates the maximal acceleration of the corrugated cardboard under the impact. However, because the maximal acceleration is not necessarily corresponding to the damage of contents, it is difficult to evaluate the impact of the corrugated cardboard only by the maximal acceleration. Also the place to measure is the center of the ground side but it is not discussed about the measuring place. In this paper, impact force is applied by a free fall test by a guide rail to drop it straight to the ground. The ID acceleration sensor, are glued in several place to make clear the difference between the measured place. From the experiment, we considered impact energy and the maximal acceleration. In addition, we made an analytical model of the corrugated cardboard to analysis to identity the damage. As a result, strain energy has a correspondence between the experiment and the analysis and the maximal acceleration didn't have it. So, the utility of the strain energy was able to be shown as a method of evaluating the impact using FEM. Through this result, we watched how the energy spread and found out the center of the ground side and the wall side has a high energy when it's impacted and when a few second pasts the wall side still has a high energy because of the vibration of the cardboard. To find out the relation between the data from the corrugated cardboard and the contents. As a result, the maximal acceleration has a strong relation between the center of the ground side and the energy has a strong relation between the middle of the center and the corner. Finally, we also considered HIC36 to evaluate the impact.

    CiNii

  • 1201 A Study on Concept Design Support Using Data Envelopment Analysis

    SATO Masaki, MIYASHITA Tomoyuki

      2010 ( 20 ) "1201 - 1"-"1201-6"  2010.10

     View Summary

    In conceptual design phase, if designers are much more conscious of design objectives, they won't come up with various ideas about new product. On the other hand, using brainstorming allow to get various ideas, but to get a lot of unavailable ideas together. In this study, to support generating various and effective ideas in conceptual design, we propose two conceptual design support methods based on Data Envelopment Analysis and Analytic Hierarchy Process. The former is the method using several evaluation values to fill the gap of palate frontier and creating hierarchy graphs. The latter is method establishing a prioritized list of all ideas by paired comparison. Various information is given to the designer from these graphs when they conceive new ideas. We verified which technique is effective to obtain new ideas with high evaluation by comparing these two methods. The result shows that the proposed method using hierarchy graphs is more efficient than the other way using the prioritization graph.

    CiNii

  • 406 Structural analysis of elastic body using Cellular Automaton and GPGPU

    SHIRAI Tomohiko, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2010 ( 23 ) 337 - 339  2010.09

    CiNii

  • Temperature dependence of thermal conductivity of liver based on various experiments and a numerical simulation for RF ablation.

    Watanabe Hiroki, Yamazaki Nozomu, Kobayashi Yo, Miyashita Tomoyuki, Hashizume Makoto, Fujie Masakatsu G

    Temperature dependence of thermal conductivity of liver based on various experiments and a numerical simulation for RF ablation.   2010  2010.09  [Refereed]

     View Summary

    :Radiofrequency ablation (RFA) for liver cancer has increasingly been used over the past few years because RFA is minimally invasive treatment for patients. However, precise control of the formation of coagulation zones is difficult for operators due to inadequate imaging modalities. With this in mind, we have proposed a model-based robotic ablation system using numerical simulation to analyze temperature distributions in the organ to overcome this deficiency. The objective of our work is to develop a temperature-dependent thermophysical organ model to construct a precise numerical simulator for RFA. However, no standard methods exist for obtaining the thermophysical properties of biological tissues, as detailed evaluations of the accuracy of properties obtained from various experiments have not been completed. The purpose of this study was thus to measure and model the temperature dependence of thermal conductivity in hog liver from three representative methods, and to compare these results using our developed numerical simulator to reveal differences in temperature distributions stemming from differences in thermal conductivities.

    DOI

  • Collapse Simulation of Lung for System to Navigate Tumor Position

    KOBAYASHI Yo, YOSHIZAWA Aiko, OKAMOTO Jun, MIYASHITA Tomoyuki, YAMAKAWA Hiroshi, FUJIE Masakatsu G

    Journal of Japan Society of Computer Aided Surgery   12 ( 1 ) 13 - 21  2010.03

     View Summary

    It is required to collapse a lung in VATS (video-assisted thoracic surgery). The tumor position is displaced corresponding to ling collapse. Then, navigation system, which presents the tumor position for a surgeon without any palpation process, may be effective for VATS. The purpose of this study is to develop the navigation system using the collapse simulation of lung. This paper shows a collapse simulation with a loaf lung, which has no lobatum, as a first step of this study. First, we obtained and modeled the material properties of hog lung from the data obtained by rheometer. The Zener's model was used to represent the viscoelastic properties of lung from the analysis of the data. Next, the biomechanical model of lung was developed based on Finite Element Method. The collapse simulation was carried out using the model. The analysis result shows the lung model was collapsing and the deformation had the similar tendency to real lung.

    CiNii

  • A improvement method of conceputual design ideas using Data Envelopment Analysis

    Miyashita, Tomoyuki, Satoh, Daisuke

    DS 58-6: Proceedings of ICED 09, the 17th International Conference on Engineering Design   6 ( PART 2 ) 13 - 22  2009.12  [Refereed]

     View Summary

    The designers often are required to derive ideas of the products satisfying requirements of users and market. To accomplish to derive good design, it is important to have much information for previous designs and collaborate with the other designers. At an early stage of design process, several designers have to derive ideas considering its evaluation in cooperation. In this stage, some existing methods to support thinking processes among several persons are useful. However, it is difficult to give a direction for discussion because a reasonable evaluation of ideas is difficult and it is also difficult for the evaluation to be accepted by the other designers. In this study, we propose a method to support generating various and effective ideas in conceptual design process. The ideas are mathematically defined to have factors of evaluation and features and numerically treated in these factors space. Data Envelopment Analysis (DEA) is applied for ideas having many factors of evaluation to derive reasonably a scalar value for evaluation result. DEA gives us a segment of many ideas and from this segment we can discuss a new idea. To support deriving a new idea, we have identified nonlinear mathematical model between factors of evaluation and features and optimization method was applied for the identified model. The proposed method is applied for the experiment and we could confirm the effectiveness of the proposed method.

  • A Study on Idea Generation Method for Concept Design Using Data Envelopment Analysis(Machine Elements, Design and Manufacturing)

    SATOH Daisuke, KOBAYASHI Masakazu, MIYASHITA Tomoyuki

    Transactions of the Japan Society of Mechanical Engineers. C   75 ( 760 ) 3355 - 3363  2009.12

     View Summary

    At an early stage of design process, it is required to discuss many ideas derived from design requirements using designer's knowledge and experiences. Especially, at conceptual design stage, many designers often discuss together about new product and discuss design ideas considering its effectiveness. However, according to increasing the complexity of the functions of products and variety of consumer's needs in recent years, it becomes difficult for designers to discuss about ideas by only conversations and figures. Then, in the conceptual design process, it is required to derive many ideas that meet the design requirement considering the complicated requirements. The derivation process of ideas often wastes the time because of the inertia of designer's thinking process. In this study, we will propose the method to support derivation process from the visualized relation using Data Envelopment Analysis. Through the experiment, we will confirm the effectiveness of our study.

    CiNii

  • 2417 Structural optimization for energy absorption in a train collision

    KOMATSUZAKI Makoto, MIYASHITA Tomoyuki

      2009 ( 19 ) 536 - 541  2009.10

     View Summary

    As compared with automobile, few train design methods for crashworthiness have been proposed. To establish it, we paid attention to double structure composed of train exterior and cabin, and designed train finite element model. We changed the position and thickness of steel plates joining these two constituents, and simulated train collision to a rigid body wall at the speed of 60 kilometer per hour. As a result of the optimization, it was shown that distortional energy in the cabin and maximum deceleration were reduced. We discussed relation of between absorbed energy and maximum deceleration, and introduced new train structure.

    CiNii

  • 2206 A study on optimization of nano-satellite structure

    SAITO Keisuke, MIYASHITA Tomoyuki, TSUNODA Hiroaki, WATANABE Kazuki

      2009 ( 19 ) 354 - 359  2009.10

     View Summary

    Recently the development of the small satellite becomes active. In general, small satellites are expected to be developed faster and cheaper than the large satellites. A cost of a piggyback satellite is often decided by weight. Therefore it is important to reduce the weight of satellite for cost. Considering the severe mechanical environment of launching, we have to design satellite structure. The natural frequency of the satellite should be higher than the value decided by the launching and the satellite should bear the loads during launch. And the satellite should be considered with the value of the moment of inertia and a center of gravity because of stability of position. In this paper, we will propose the design of the satellite whose dimension is 20 centimeters cube. We focused on the trade-off design between minimization of stress condition and the appropriate center of gravity and the moment of inertia under the minimum natural frequency and the maximum mass for optimizing the satellite structures.

    CiNii

  • 1907 The real time needle inset simulation considering inside deformation

    YOSHITAKE Yusuke, MIYASHITA Tomoyuki

    The Computational Mechanics Conference   2009 ( 22 ) 591 - 592  2009.10

    CiNii

  • G1201-1-1 A Study of an evaluation of a safety behavior of the passengers in the railroad impact

    SHIMADA Masayuki, MIYASHITA Tomoyuki

      2009 ( 4 ) 193 - 194  2009.09

     View Summary

    This study treats human body model and cellular automata for analysis of the passenger behavior for the deceleration at the time of the railway accident. At this case, the deceleration obtained from simulation of the railroad carriage model is used for simulation suppose to collision to the rigid body wall. Consequently, it was shown that injury to the passenger was able to be reduced by the parameter of the partition and the floor when accident was occured.

    CiNii

  • 3・4 CAE・最適化等についての研究動向(3.計算力学,<特集>機械工学年鑑)

    宮下 朋之

    日本機械学會誌   112 ( 1089 ) 615 - 616  2009.08

    CiNii

  • A study on idea generation method for concept design using data envelopment analysis

    Daisuke Satoh, Masakazu Kobayashi, Tomoyuki Miyashita

    Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C   75 ( 760 ) 3355 - 3363  2009

     View Summary

    At an early stage of design process, it is required to discuss many ideas derived from design requirements using designer's knowledge and experiences. Especially, at conceptual design stage, many designers often discuss together about new product and discuss design ideas considering its effectiveness. However, according to increasing the complexity of the functions of products and variety of consumer's needs in recent years, it becomes difficult for designers to discuss about ideas by only conversations and figures. Then, in the conceptual design process, it is required to derive many ideas that meet the design requirement considering the complicated requirements. The derivation process of ideas often wastes the time because of the inertia of designer's thinking process. In this study, we will propose the method to support derivation process from the visualized relation using Data Envelopment Analysis. Through the experiment, we will confirm the effectiveness of our study.

    DOI

  • 835 An Evaluation of The Real-time Needle Insertion Simulation System

    YAMANAKA Masaki, MIYSITA Tomoyuki

    The Computational Mechanics Conference   2008 ( 21 ) 642 - 643  2008.11

     View Summary

    The simulation system that calculates the behavior of the liver by needle insertion in real time, displays the results, and outputs the reaction force to the kinesthetic sense device was developed. The finite element method was used for the calculation of the behavior of the liver. Considering the calculation load, the algorithm to achieve the real-time processing was developed. The simulation system was evaluated from calculating load by using the liver models with different number of elements. It was the model with 905 elements and 209 nods that met the requirement for the real-time processing (calculation speed is 30Hz or more).

    CiNii

  • 908 A Study of an evaluation of a safety between human and car equipment in the railroad impact

    KATAOKA Kosuke, MIYSITA Tomoyuki

    The Computational Mechanics Conference   2008 ( 21 ) 73 - 74  2008.11

     View Summary

    This study treats the reduction of the degree of the passenger injury by analyzing the behavior of 133 passengers being in a commuter vehicle at the time of the impact of the railroad accident outbreak with a computer. Judgment the degree of the injury of the passengers and inspection of the global safety was enabled by developing the behavior analysis program of the passengers with cellular automata with C language and analyzing with a large number of people. In addition, the safety improvement effect of the straps was confirmed by comparing the injury judgment value of the model increased the number of the straps to the normal model.

    CiNii

  • 3305 A Study on Derivation of Design index using Vehicle Structure and Performance Data By Data Envelopment Analysis

    FUKUNISHI Hirotomo, MIYSITA Tomoyuki

      2008 ( 18 ) 529 - 534  2008.09

     View Summary

    In this research, we analyzed the automotive data that contain bringing the automotive performance from about 300000 models from which they were open to the public from 1982 to 2006 years about 20000 models by Data Envelopment Analysis. DEA is the method that can make clear superiority or inferiority of business unit with multi-dimensional index and showing improvement direction of business unit. As a result, we can show trends from graph where horizontal axis was assigned as each performance index and vertical axis was assigned as each efficiency value obtained by DEA. We showed design index of automotive in the future by sensitivity analysis. From the above-mentioned method, we can confirm DEA is the effective method as method of evaluating products with multi-dimensional index.

    CiNii

  • 1111 A Fundamental Examination on a Concept Design Support using Neural Network

    SATOH Daisuke, MIYASHITA Tomoyuki

      2008 ( 18 ) 77 - 82  2008.09

     View Summary

    In conceptual design phase, if designers are much more conscious of design objectives, they won't come up with various ideas about new product. On the other hand, using brainstorming allow to get various ideas, but to get a lot of unavailable ideas together. In this study, we propose the method that supports generating various and effective ideas in conceptual design. In the last our study, we have proposed conceptual design support method using Data Envelopment Analysis. The last method's approach is using several evaluation values to fill the gap of palate frontier. But it was too difficult for subjects to use this approach in the experiment. Proposed method in this paper supplies key words. These key words are made of calculated component values using made nonlinear mathematical model of relation between component and evaluation of idea with Neural Network. We confirm that the method is useful in terms of simplicity of generating various and effective ideas.

    CiNii

  • 3116 A study on optimization of nano-satellite structure

    SAITO Keisuke, MIYASHITA Tomoyuki, TSUNODA Hiroaki, WATANABE Kazuki

      2008 ( 18 ) 441 - 446  2008.09

     View Summary

    Recently the development of the small satellite becomes active. In general, small satellites are expected to be developed faster and cheaper than the large satellites. The launching cost of the piggyback satellite is low, and then a cost of a piggyback satellite is often decided by weight. Therefore it is important to reduce the weight of satellite for cost. Considering the severe mechanical environment of launching, we have to design of satellite structure. The natural frequency of the satellite should be higher than the value decided by the rocket and the satellite should withstand the loads during launch. In this paper, we will propose the design of the satellite whose dimension is 20 centimeters cube. The satellite supposed to be launched by H-2A rocked and we focused on the trade-off design between minimization of mass and maximization of natural frequency under the maximum stress condition for optimizing the satellite structures.

    CiNii

  • Collaboration Support System Based on Assessment of Created Ideas Using Data Envelopment Analysis(Machine Elements and Manufacturing)

    KOBAYASHI Masakazu, MIYASHITA Tomoyuki, YAMAKAWA Hiroshi, YOSHIMURA Masataka

    Transactions of the Japan Society of Mechanical Engineers. C   74 ( 738 ) 459 - 466  2008.02

     View Summary

    This paper focuses on the creative aspects of collaboration and proposes a method for analyzing created ideas to help designers to enhance designers' creativity during collaborative design projects. The proposed method is based on DEA (Data Envelopment Analysis), analyses ideas created by designers to reveal characteristics and overall effectiveness of each idea, interrelationship between ideas and potentially fruitful directions for improvement of created ideas and exploration of new ideas and aims to help designers explore more sophisticated ideas. To enable smooth collaboration when using the proposed analysis method, this paper also proposes a computerized support system. This system is based on a combination of the analysis method proposed here, and the method for visualizing interactive communication processes proposed in our previous work. Analyzing system analyzes created ideas and visualizes the results from the multiple viewpoints, whereas visualizing system records interactive communication processes among designers and visualizes them in an easyto-understand way.

    CiNii

  • 1P1-C10 Robotic heart-beat simulator to evaluate a surgical robot system with heart-beat canceller

    OKADA Kaoru, KATO Atsuhi, NOGUCHI Toyohiro, TOYODA Kazutaka, KAWAMURA Kazuya, KOBAYASHI You, OKAMOTO Jun, MIYASHITA Tomoyuki, FUJIE Masakatsu G.

    The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec)   2008 ( 0 ) _1P1 - C10_1-_1P1-C10_4  2008

     View Summary

    This paper presents the development of robot capable to simulate heartbeat. It is difficult to operate off-pump coronary-artery bypass surgery. Consequently, we develop the surgical robot system with heart-beat compensation. In the process of developing the robot system above, it is necessary to evaluate the tracking capability of the robot system quantitatively. Therefore, we developed the Robotic heart-beat simulator which evaluates the robot system. First of all, required specification of the robot was found by the heartbeat data in vivo experiment. Second, the link parameters of the robot that satisfy the specification were optimized. At the end, the robot was evaluated for accuracy of position and posture. As a result, the robot moved with maximum error of 0.28 [mm] and 0.54 [deg]. In addition, the robot was evaluated in the experiment of movement based on the heartbeat data, it showed a little error and time-lag, but utility of the robotic heartbeat simulator.

    DOI CiNii

  • 2106 Fundamental Study using Vehicle Structure and Performance Data By Data Envelopment Analysis

    FUKUNISHI Hirotomo, MIYSITA Tomoyuki

      2007 ( 17 ) 119 - 120  2007.10

     View Summary

    In this research, we analyzed the automotive market bringing the automotive performance from about 300000 models from which they were open to the public from 1982 to 2006 years about 20000 models by Data Envelopment Analysis. DEA is the method that can make clear about superiority or inferiority of business unit with multi-dimensional index and showing improvement of business unit. As a result, we can show trends from graph where horizontal axis was assigned as each performance index and vertical axis was assigned as each efficiency value obtained by DEA. We showed design index of automotive in the future by sensitivity analysis. From the above-mentioned method, we can confirm DEA is the effective method as method of evaluating products with multidimensional index.

    CiNii

  • 2306 The safety of the passenger in the railroad collision

    KATAOKA Kosuke, MIYSITA Tomoyuki, YAMAKAWA Hirosi

      2007 ( 17 ) 189 - 192  2007.10

     View Summary

    This study treats the reduction of the degree of the passenger injury by analyzing the behavior of the passenger sitting on a box seat at the time of the collision outbreak of the railroad carriage by simulation. Judgment the degree of the passenger injury was enabled by development the behavior analysis program of the passenger with C language and inputting a decelerating acceleration wave pattern at the time of the vehicle collision obtained by the finite element analysis. Injury judgment values decreased by more than 30% by optimizing to assume the spring constant of the seat as a design variable to reduce an injury judgment value.

    CiNii

  • Development and evaluation of the Needle Insertion Surgery Simulation System

    Nakamura Takuma, Miyashita Tomoyuki, Yamakawa Hiroshi

    Proceedings of JSPE Semestrial Meeting   2007 ( 0 ) 141 - 142  2007

     View Summary

    The surgery simulation system for training purpose is useful for training and planning. The system displays the deformation of the human organs calculated using Finite Element Method (FEM) and output the reaction forces with force feedback devices. However, FEM prevents a real time simulation because of high computational cost. In this study, we have developed a Needle Insertion Surgery Simulation System, which has the ability to compute reaction forces and simulates dynamical behaviors in real time using a simple calculation method. Here, we have proposed and discussed a simple method to compute reaction forces from internal stress distribution, which is calculated using FEM. Considering the DOF of the model and computational cost; we have discussed the effectiveness of the proposed method, and the possibility to develop the system.

    CiNii

  • Designing the Path and Retainer Tools for Needle Insertion Surgery

    Md.Kzamani, T.Miyashita, Y.Kobayashi, H.Yamakawa, J.Okamoto, Masakatsu.G.Fujie

    Proceedings of JSPE Semestrial Meeting   2007 ( 0 ) 137 - 138  2007

     View Summary

    The minimal invasive surgical technique used for treatments on cancer infected liver is comparatively to be effective due to fast recovery of the wound and the rehabilitation period. Needle insertion planning shows its difficulties when needle contact the tissue structures and become complicated with existence of gravity, cancer size and position, needle properties and surrounding organs. In this study, a constitutive equation of viscoelastic material properties of liver is formulated using measured experimental results on pig′s liver. 3-D Finite Element Model is created using sliced MRI images. Approximations were made on friction between needle and soft tissue, and the condition of tear-off elements integrated with quasi-static analysis. In simulation, we proposed a retainer tool to minimize the displacement of the cancer infected part as a new boundary condition. Numerical results by proposed boundary condition technique show the possibility to design a new device in order to navigate needle to hit the cancer precisely.

    CiNii

  • A Fundamental Examination on a Conceptual Design Support using Data Envelopment Analysis

    Satoh Daisuke, Miyasita Tomoyuki

    Proceedings of JSPE Semestrial Meeting   2007 ( 0 ) 543 - 544  2007

    CiNii

  • A simulation method for 3-dimension needle invasive medical treatments of cancer infected liver

    Kemarol zamani, Miyashita Tomoyuki, Hiroshi Yamakawa

    PROCEEDINGS OF THE FIFTH IASTED INTERNATIONAL CONFERENCE ON BIOMEDICAL ENGINEERING     43 - 49  2007  [Refereed]

     View Summary

    The medical insertion treatments on cancer infected liver seem to be very effective because of low invasion for patients. Planning for insertion procedure is difficult because the interaction between needle and soft tissue become complicated and the liver may deform largely under the influence of such gravity, cancer, position of needle and so on. It is of significant to grasp natural properties and deformations of liver during medical needle insertion. In this study, viscoelastic material properties are measured by experiments and constitutive equation is formulated based on the experimental results. Then a liver is modeled by finite elements made from the sliced MRI images. 3-Dimensional needle insertion procedures are simulated by quasi-static analysis assuming friction between the needle and soft tissue and conditions of tear-off elements. From the numerical results by the proposed simulation method, it is found that some navigation of the needle insertion is necessary to hit the cancer correctly.

  • Physical Model of Organ for Needle Insertion Procedure

    YAMAKAWA Hiroshi, ZAMANI MD Kemarol, NAKAMURA Takuma, KAWAMURA Kazuya, KOBAYASHI Yo, OKAMOTO Jun, MIYASHITA Tomoyuki, FUJIE Masakatsu G.

      8 ( 3 ) 140 - 141  2006.12

    CiNii

  • Particle swarm optimization using projection matrix for behavior constraints

    Miyashita, Tomoyuki

    Collection of Technical Papers - 11th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference   1   122 - 128  2006.12

     View Summary

    Particle Swam Optimization is one of useful optimization method that has a global search ability and is easy to implement. However there are some difficulties are observed for behavior constraints. This paper proposes a new approach to treat behavior constrains by projection of velocity vector of particles. By projection of velocity vector particks could approach feasible region formed by active constraints. Through several numerical examples, it is recognized better converge performance than original PSO. Copyright © 2006 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

  • 3201 An Optimal Design of Partially Rigidizable Inflatable Structures

    Sato Nobuaki, IWAKOSHI Tomoyuki, TSUNODA Hiroaki, YAMAKAWA Hiroshi, MIYASHITA Tomoyuki

      2006 ( 6 ) 111 - 112  2006.09

     View Summary

    In this study, we proposed partially rigidizable inflatable structures consist of rigidizable layers on the part where to be stiffened. As a result of tension test of the test specimen, we could make the property of the material clear. Furthermore, we made a initial model that wholly covered hemisphere structural model and the topology optimization was applied to find the optimum arrangement of regidizable layers. As a result, the number of edge reduced to 35 lines, and considering the volume to 11% lower than that of the basic model. From the point of view of manufacturing, stiffness and stress concentration, we could suppose that the basic model is suitable for our required.

    CiNii

  • 117 A collaborative support method based on analysis of created ideas

    KOBAYASHI Masakazu, MIYASHITA Tomoyuki, YAMAKAWA Hiroshi, YOSHIMURA Masataka

      2006   105 - 108  2006.07

     View Summary

    This paper focuses on the creative aspects of collaboration and proposes a method for analyzing created ideas to support collaborative design processes. The proposed method, based on DEA (Data Envelopment Analysis), analyses created ideas, reveals their characteristics and interrelationships, clarifies potential directions for improvement of created ideas as well as potentially fruitful directions for exploration of new ideas, and aims to help designers explore more sophisticated products. To enable smooth collaboration when using the proposed method, a computerized support system is constructed. This system is based on a combination of the analysis method proposed here, and the method for visualizing interactive communication processes proposed in our previous work.

    CiNii

  • 2A1-A03 Development of a Respiratory Surgical Navigation System for Identifying a Position of a Metastasis Cancer in a Collapsed Lung

    YOSHIZAWA Aiko, KOBAYASHI Yo, OKAMOTO Jun, MIYASHITA Tomoyuki, YAMAKAWA Horoshi, FUJIE Masakatsu G

      2006   "2A1 - A03(1)"-"2A1-A03(4)"  2006

     View Summary

    This paper shows the development of a respiratory surgical navigation system for the metastasis cancer in a collapsed lung. This system has two navigation methods, (a) Collapsed simulation,(b) Palpation using manipulator. Collapsed simulation provides the position of the cancer in a collapsed lung using the preoperative CT Data. Palpation using manipulator after collapsed simulation provide more precise position of collapsed lung.

    CiNii

  • 2P1-C03 A Real Time Simulation using Finite Element Method : Confirmation using Haptic Device

    YAMAUCHI Hiroshi, MIYASHITA Tomoyuki, INUI Masatomo, YAMAKAWA Hiroshi

      2006   "2P1 - C03(1)"-"2P1-C03(4)"  2006

     View Summary

    In this study, we will review the previous studies treating same problem using FEM analysis and propose the method to treat the cutting simulation considering real time computation and simulation results are directly transferred to the user through the haptic device. The hex and tetra elements were used to model the structure using FEM analysis and dynamical response was calculated using wilson θ method. Here, the elements matrix was normalized according to the distance between a cutting device and nodes to omit the re-mesh procedures. The proposed method was implemented using three threads that handle graphics for display, dynamical calculation and model construction to improve the response for user operation. Then, we have developed the simulation system composed of the haptic device (PHANToM force feedback device) using ToolKit and the proposed method including graphics animation.

    CiNii

  • Inverse Offset of Z-map Model for Process Planning Assistance

    Proc. of ISATP2005(IEEE)   Proc. of ISATP2005  2005.07  [Refereed]

  • The Multi-objective collaborative design using data envelopment analysis

    Proc. of IFIP2005(IEEE)   Proc. of IFIP2005  2005.07

  • Inverse Offset of Z-map Model for Process Planning Assistance

    米国電気学会   Proc. of ISATP2005  2005.07  [Refereed]

  • The Multi-objective collaborative design using data envelopment analysis

    米国電気学会   Proc. of IFIP2005  2005.07

  • Cutting Simulation using Haptic Device

    JSPE Precision Engineering Conference (Spring) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2005.03

  • An Examination for structural optimization algorithm using GPU

    JSPE Precision Engineering Conference (Spring) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2005.03

  • A Examination for improvement of PSO method considering Projection of Search Direction

    JSPE Precision Engineering Conference (Spring) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2005.03

  • 力覚デバイスによる物体切断シミュレーション

    日本精密工学会   春季大会講演論文集  2005.03

  • GPUを利用した二次元応力場における簡易計算と最適化の検討

    日本精密工学会   春季大会講演論文集  2005.03

  • 探索方向の傾斜によるPSO法の改良に関する検討

    日本精密工学会   春季大会講演論文集  2005.03

  • Cutting Simulation with Force Feedback Device

    Inui Masatomo, Miyashita Tomoyuki, Yamauchi Hiroshi

    Proceedings of JSPE Semestrial Meeting   2005 ( 0 ) 239 - 240  2005

     View Summary

    While calculation of reaction force in object cutting, we have to subdivide the original mesh of finite element method in the field where the stress concentration can be observed. It causes a huge computational complexity. We constructed object cutting simulation system that is able to output reaction force to force feedback device using OpenGL library. The system consists of high speed deformation calculation using rough mesh, and static and dynamic calculation method of calculates reaction force to cutting tool.

    CiNii

  • An Application of Database For Design Optimization to Derive Quasi-Optimum Solutions

    Proc. of CJK-OSM3   Proc. of CJK-OSM3  2004.11

  • A Study on Collaborative Optimization using Data Envelopment Analysis and Cutting Plane Method

    Proc. of CJK-OSM3   Proc. of CJK-OSM3  2004.11

  • An Application of Database For Design Optimization to Derive Quasi-Optimum Solutions

    日本・中国・韓国機械学会   Proc. of CJK-OSM3  2004.11

  • A Study on Collaborative Optimization using Data Envelopment Analysis and Cutting Plane Method

    日本・中国・韓国機械学会   Proc. of CJK-OSM3  2004.11

  • Development and Basic Study of Parameter Study tools

    JSME Mechanical Engineering Congress /JSME   No.04-01  2004.09

  • An improvement of Accuracy of Cutting Simulation for Z-map expression using normal line

    JSPE Precision Engineering Conference (Autumn) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2004.09

  • パラメータスタディツールの開発と基礎的検討

    日本機械学会   機講論 No.04-01  2004.09

  • 面法線情報を伴うZ-マップ表現を利用した加工シミュレーションの高精度化

    日本精密工学会   秋季大会講演論文集  2004.09

  • Structural Optimization using Trade-off Satisficing Method

    Proc. of Int. Conf. of MCDM   Proc. of Int. Conf. of MCDM  2004.08

  • Structural Optimization using Trade-off Satisficing Method

    Int. Soc. Of MCDM   Proc. of Int. Conf. of MCDM  2004.08

  • An application of Discrete shape expression considering normal line information]

    JSPE Precision Engineering Conference (Spring) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2004.03

  • A Development of Parameter Study Tools for Design Opotimization

    JSME Mechanical Engineering Congress /JSME   No.040-1  2004.03

  • A Study on Collaborative Design using Data Envelopment Analysis

    JSME Mechanical Engineering Congress /JSME   No.040-1  2004.03

  • 法線情報を伴う離散的形状表現のCAMでの利用

    日本精密工学会   春季大会講演論文集  2004.03

  • 最適設計におけるパラメータスタディツールの開発

    日本機械学会   機構論 No.040-1  2004.03

  • データ包絡分析法による協調設計に関する研究

    日本機械学会   機構論 No.040-1  2004.03

  • A study on immune algoriths considering interaction of design with environment properties

    Miyashita, Tomoyuki, Yamakawa, Hiroshi

    Proceedings of the ASME Design Engineering Technical Conference   2 B   945 - 950  2003.12

     View Summary

    In design problems, designers have to decide many properties of products to satisfy requirements from users or market. The designers also have to consider the environment under the use of the products and the environment is often unpredictable or difficult to be determined in detail. The optimization techniques are useful to support the designers to decide the properties of the product. However, it is required before the application of the optimization techniques to formulate mathematical models and it is difficult to formulate the all properties of products, for examples preferences of the customer. In this situation, it seems to be useful to derive several solutions that equip the variety or diversity about the value of design variables or objective functions. In this paper, the new method to derive several solutions using immune algorithms is described. The proposed method equips the interaction mechanism between the design parameter and the environment parameters. Through some numerical examples of the structural design problems and job-shop scheduling problems, the effectiveness is confirmed.

  • Development of Genetic Range Genetic Algorithms

    Trans of JSME Series C/JSME   70-695C  2003.10

  • An Examination on Jobshop Scheduling Problem in cosideration of diversity

    JSME Mechanical Engineering Congress /JSME   No.02-01  2003.10

  • A Generation of geometoricaly smooth tool path based on discrete shape expression

    JSPE Precision Engineering Conference (Autumn) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2003.10

  • 領域遺伝型遺伝的アルゴリズムの開発

    日本機械学会   機論(C) No.70-695  2003.10

  • 多様性を考慮したジョブショップスケジューリング問題の検討

    日本機械学会   機構論 No.02-01  2003.10

  • 離散的な形状表現に基づく幾何学的に滑らかな工具経路の生成

    日本精密工学会   秋季大会講演論文集  2003.10

  • Genetic Range Genetic Algorithm to Obtain Quasi-Optimum Solutions

    Proc. of ASME 2003 Int. Design Eng. Tech. Conf. and the Comp. and Information in Eng. Conf.   CD-ROM of DETC DAC34051  2003.09

  • A Study on Immune Algorithms Considering Interaction of Design with Environment Properties

    Proc. of ASME 2003 Int. Design Eng. Tech. Conf. and the Comp. and Information in Eng. Conf.   CD-ROM of DETC DAC48802  2003.09

  • Range Zooming for Genetic Range Genetic Algorithms

    Proc. of WCSMO5   Proc. of WCSMO5  2003.09

  • Errors in Optimization using the Response Surface Method and Resulting Physical Phenomena

    Proc. of WCSMO5   Proc. of WCSMO5  2003.09

  • An Examination of Immune Algorithm for Structural and Production Design

    Proc. of WCSMO5   Proc. of WCSMO5  2003.09

  • Genetic Range Genetic Algorithm to Obtain Quasi-Optimum Solutions

    米国機械学会   CD-ROM of DETC DAC34051  2003.09

  • A Study on Immune Algorithms Considering Interaction of Design with Environment Properties

    米国機械学会   CD-ROM of DETC DAC48802  2003.09

  • Range Zooming for Genetic Range Genetic Algorithms

    ISSMO   Proc. of WCSMO5  2003.09

  • Errors in Optimization using the Response Surface Method and Resulting Physical Phenomena

    ISSMO   Proc. of WCSMO5  2003.09

  • An Examination of Immune Algorithm for Structural and Production Design

    ISSMO   Proc. of WCSMO5  2003.09

  • An Application of Immune Algorithms for Job-Shop Scheduling Problems

    Proc. of ISATP2003(IEEE)   ISATP2003  2003.07  [Refereed]

  • Hollow shape extraction: Geometric method for assisting process planning of mold machining

    Proc. of ISATP2003(IEEE)   ISATP2003  2003.07  [Refereed]

  • An Application of Immune Algorithms for Job-Shop Scheduling Problems

    Proc. of ISATP2003(IEEE)   ISATP2003  2003.07

  • Hollow shape extraction: Geometric method for assisting process planning of mold machining

    米国電気学会   ISATP2003  2003.07  [Refereed]

  • A Development of Collaborative Design System using Data Envelopment Analysis

    JSPE Precision Engineering Conference (Spring) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2003.03

  • データ包絡法を用いた協調設計システムの構築

    日本精密工学会   春季大会講演論文集  2003.03

  • A Study on Collaborative Design Considering Features of Design

    Proc. of ASME 2002 Int. Design Eng. Tech. Conf. and the Comp. and Information in Eng. Conf.   CD-ROM of DETC DAC34051  2002.10

  • A Study on Collaborative Design Considering Features of Design

    Miyashita, Tomoyuki, Yamakawa, Hiroshi

    米国機械学会   CD-ROM of DETC DAC34051   155 - 159  2002.10

     View Summary

    In design processes of machinery, much computer software, for examples CAD/CAE/CAM software, are used. The design processes are aided by this software. The seamless connections of the design processes are necessary for the improvement of the cost benefit of the products. However, sometimes, the conflicts among designs or design processes are occurred by the change of the design at a certain design process and these conflicts are should be noticed and solved immediately. In this research, we have developed the design system including CAD software and the developed system has some functions to find the conflicts of the change of designs and to solve the conflicts. We use Data Envelopment Analysis (DEA) to calculate the efficiency of the design and Satisficing Trade-off Method (STM) to find and solve the conflicts. We have confirmed through some fundamental numerical examples and discussed of the proposed system and method and showed the effectiveness of out study.

  • A Study on Structural Optimization using Immune System

      2002 ( 7 ) 193 - 194  2002.09

     View Summary

    Optimization techniques are useful to determine the unknown parameter according to the evaluations of design. This techniques require to be formulated mathematically. Then the indexes that is difficult to express mathematically, for examples "kansei" are difficult to be included in the optimization problems. In this study, we will propose the algorism based on immune algorithms and try to derive some candidates including solution. immune algorithms are considered as the optimization algorithms. However, the immune algorithms are not fully established becase various algorithms are considered and fully investigated. In this study, from above point of view, we will propose the immune algorithm that treates the "antibody-antigen reaction". Through some numerical examples, we will show the effectivenews of th proposed algorithm.

    CiNii

  • A Study on Gradient Based Search Agents in Global Optimization

    Proc. of 10th Symposium on Multidisciplinary Analysis and Opt./AIAA   CD-ROM of MAO, AIAA2002-5508  2002.09

  • A Generation method for tool path using Inverse Offset Plane

    JSPE Precision Engineering Conference (Autumn) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2002.09

  • A Discussion on Job-shop Scheduling Problem considering Environment Properties

    JSPE Precision Engineering Conference (Autumn) / JSPE   Proc. of JSPE Conf. (CD-ROM)  2002.09

  • A Study on Structural Optimization using Immune System

    JSME Mechanical Engineering Congress /JSME   No.02-01  2002.09

  • A Study on Gradient Based Search Agents in Global Optimization

    米国航空宇宙学会   CD-ROM of MAO, AIAA2002-5508  2002.09

  • 金型粗加工のための逆オフセット面に基づく工具経路の生成手法

    日本精密工学会   秋季大会講演論文集  2002.09

  • 多様性を考慮したジョブショップスケジューリングの決定

    日本精密工学会   秋季大会講演論文集  2002.09

  • 免疫システムによる設計最適化に関する研究

    日本機械学会   機構論No.02-01  2002.09

  • A Study on the Collaborative Design using Supervisor System

    Trans of JSME Series C/JSME   JSME Int. J. Series C  2002.03

  • A Study on the Collaborative Design using Supervisor System

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    日本機械学会   JSME Int. J. Series C ( 1 ) 333 - 341  2002.03  [Refereed]

     View Summary

    In recent years, financial difficulties led engineers to look for not only the efficiency of the function of a product but also the cost of its development. In order to reduce the time for the development, engineers in each disciplinary have to develop and improve their objectives collaboratively. Sometimes, they have to cooperate with those who have no knowledge at all for their own disciplinary. Collaborative designs have been studied to solve these kinds of the problems, but most of them need some sorts of negotiation between disciplines and assumed that the negotiation will be done successfully. However, in the most cases of real designs, manager of each disciplinary does not want to give up his or her own objectives to stress on the other objectives. In order to carry out these negotiation smoothly, we need some sort of evaluation criteria which will show efficiency of the product considering the designs made up by each division and if possible, considering the products of the competitive company. In this study, we use Data Envelopment Analysis (DEA) to calculate the efficiency of the design and showed every decision maker the directions of the development of the design. We newly called these kinds of systems as supervisor systems and implemented these systems in computer networks that every decision makers can use conveniently. Through simple numerical examples, we showed the effectiveness of the proposed method.

    CiNii

  • Optimum design using search agents

    Miyashita, Tomoyuki, Yamakawa, Hiroshi

    Proceedings of the ASME Design Engineering Technical Conference   2   19 - 26  2001.12

     View Summary

    Many optimization methods and practical softwares have been developing for many years and most of them are very effective, especially to solve practical problems. But, non-linearity of objective functions and constraint functions, which have frequently seen in practical problems, has caused a difficulty in optimization. This difficulty mainly lies in the existence of several local optimum solutions. In this study, we have proposed a new global optimization methodology that provides an information exchange mechanism in the nearest neighbor method. We have developed a simple software system, which treated each design point in optimization as an agent. Many agents can search the optima simultaneously exchanging the their information. We have defined two roles of the agents. Local search agents have roles on searching local optima by such an existing method as the steepest decent method and so on. Stochastic search agents investigate the design space by making use of the information from other agents. Through simple and several structural optimization problems, we have confirmed the advantages of the method.

  • A Study on the Optimum Design Using Search Agents

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    Transactions of the Japan Society of Mechanical Engineers. C   67 ( 662 ) 3227 - 3235  2001.10

     View Summary

    Many optimization methods and practical softwares have been developing for many years and most of them are very effective, especially to solve practical problems. But, non linearity of objective functions and constraint functions, which have frequently seen in practical problems, has caused a difficult situation for optimization. This difficulty mainly lies in the existence of several local optimum solutions. In this study, we have proposed a new global optimization methodology that provides an information exchange mechanism in the nearest neighbour method. We have developed a simple software system, which treated each design point in optimization as an agent. Many agents can search the optima simultaneously exchanging the their information. We have defined two roles of the agents. Local search agents have roles on searching local optima by an existing method like the steepest decent method and so on. Stochastic search agents investigate the design space by making use of the information from other agents. Through simple and several structural optimization problems, we have confirmed the advantages of this method.

    CiNii

  • A Study on the Optimum Design Using Search Agents

    Trans of JSME Series C/JSME   67-662C  2001.10

  • 探索エージェントによる最適設計に関する研究

    日本機械学会   機論(C) No. 67-662  2001.10

  • Optimum Design Using Search Agents

    Proc. of ASME 2001 Int. DETC and CIE/ASME   (DAC14532)  2001.09

  • Optimum Design Using Search Agents

    Proc. of ASME 2001 Int. Design Eng. Tech. Conf. and the Comp. and Information in Eng. Conf.   Paper No. DAC14532  2001.09

  • 免疫エージェントによる最適設計に関する研究

    日本機械学会   No.01-01  2001.08

  • K-0215 A Study on Structural Optimization using Immune System

      0 ( 1 ) 53 - 54  2001.08

     View Summary

    Immune system in mammals plays a significant role on the survival in the case with attacking of various bacteria. This system seems to equip the mechanism eliminate the various vacteria. From the view point of information mechanism, this system could offer the designs that are considered with the environmental situation, for example, wind loads, deterioration and so on. Especially, immune algorithms are considered as the optimization algorithms. However, the immune algorithms are not fully established becase various algorithms are considered and fully investigated. In this study, from above point of view, we will propose the immune algorithm that treates the "antibody-antigen reaction". Through some numerical examples, we will show the effectivenews of th proposed algorithm.

    CiNii

  • A Study on Structural Optimization using Immune System

    JSME Engineering Congress/JSME   No.01-01 (??)  2001.08

  • データ包絡分析法と設計者の交渉過程を考慮した協調設計システムの開発とその検討

    土木学会    2001.07

  • A Study on Optimum Design using Search Agents

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    Trans of JSME Series C/JSME   6 ( 2 ) 699 - 702  2001.05

    CiNii

  • A Study on Optimum Design using Search Agents

    Proc. of JSCES Conf./JSCES   (??)  2001.05

  • Report of Design Optimization and Satisfaction Research Commitee

    Report of JSCES/JSCES   (??)  2001.05

  • 「多目的最適化設計・満足化設計」

    日本計算工学会   研究分科会活動報告書  2001.05

  • 探索エージェントによる多点同時探索戦略による最適設計に関する研究

    日本計算工学会   日本計算工学会講演論文集  2001.05

  • 協調設計システムの検討-複合領域問題の検討-

    日本機械工学会   機構論 No.00-34, 172-175  2001.03

  • An Examination on Collaborative Design System : Treatement of Multidisciplinary Design Problem

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

      2001 ( 10 ) 172 - 175  2001.01

     View Summary

    Recent years, computational power has been incresing and designers could discuss design problems from several points of view. In these discussions, simulations using computers could offer useful information to evaluate their designs to develop profitable products exceeding the competitor's product. Optimization methods offer reasonable design canditates. However, in the design in which some technical fields are included, it is difficult to make decision to settle design canditates. In our previous study, we have proposed the method that led designers to collaboration and developed the software system. In this paper, we have examined the developed system through the some design problems.

    CiNii

  • An Examination on Collaborative Design System

    Proc. of Design Eng. and System Conf./JSME   No.00-34 (172-175)  2001.01

  • An examination on the supervisor system in multidisciplinary design optimization under conflict objects

    Miyashita, Tomoyuki, Miyashita, Tomoyuki, Yamakawa, Hiroshi, Yamakawa, Hiroshi

    8th Symposium on Multidisciplinary Analysis and Optimization    2000.12

     View Summary

    In the design of products, the designers often have to improve some objects and to satisfy some constraints. Furthermore, these days, it is more important than before to design and develop the products shortly and to commercialize the products for the profit. These needs time-consuming decision-makings and we often treat this problem as multi-objective design problems. However it is difficult for the designers who have no knowledge of the other disciplines when to decide the design collaboratively. Therefore, in this paper, we proposed a method to show some compromise to the designers and developed a system operated through computer network. © 2000 The American Institute of Aeronautics and Astronautics Inc. All rights reserved.

  • An Examination and A Development of the Collaborative Optimization System on Computer Network : Applying the Trade-off Satisficing Method

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

      2000 ( 4 ) 205 - 210  2000.10

     View Summary

    Recent years, financial difficulties led engineers to look for not only the efficiency of the function of a product but also the cost of its development. In order to reduce the time for the development, engineers in each discipline have to develop and improve their objectives collaboratively. Sometimes, they have to cooperate with those who have no knowledge at all for their own disciplines. Collaborative designs have been studied to solve these negotiations will be done successfully. However, in the most cases of real designs, manager of each discipline does not want to give up his or her own objectives to stress on the other objectives. In order to carry out these negotiations smoothly, we need some sort of evaluation criteria which will show efficiency of the product considering the designs by each division and if possible, considering the products of the competitive company, too. In this study, we use data Envelopment Analysis (DEA) to calculate the efficiency of the design and showed every decision maker the directions of the development of the design. We will call here these kinds of systems as supervisor systems and implemented these systems in computer networks that every decision maker can use conveniently. Through simple numerical examples, we showed the effectiveness of the proposed method.

    CiNii

  • An Examination and A Development of the Collaborative Optimization System on Computer Network

    Proc. of System Optimization Symposium   (205-210)  2000.10

  • ネットワークを利用した協調的最適設計システムの構築及び検討

    日本機械学会   最適化シンポジウム講演論文集 205-210  2000.10

  • An Examination on the Supervisor System in the Multidisciplinary Design Optimization under Conflict Objectives

    Proc. of 8th Symposium on Multidisciplinary Analysis and Opt./AIAA   (AIAA2000-4724)  2000.09

  • A Study on the Collaborative Design Using Trade-off Satisficing Method

    Proc. of ASME 2000 Int. DETC and CIE /ASME   (DAC21011)  2000.09

  • A Study on the Collaborative Design Using Trade-off Satisficing Method

    Proc. of ASME 2000 Int. Design Eng. Tech. Conf. and the Comp. and Information in Eng. Conf.   Paper No. DAC21011  2000.09

  • An Examination on the Supervisor System in the Multidisciplinary Design Optimization under Conflict Objectives

    Proc. of 8th Symposium on Multidisciplinary Analysis and Opt.   Paper No. AIAA2000-4724  2000.09

  • An Examination on Structural Optimization using Immute Agents

    JSME Mechanical Engineering Congress/JSME   (151-152)  2000.08

  • 免疫エージェントによる最適設計に関する研究

    日本機械学会   機講論 No.00-01,151-152  2000.08

  • An Examination on Structural Optimization using Immute Agents : An Examination on An Antigen-Antibody Reaction

      2000 ( 1 ) 151 - 152  2000.07

     View Summary

    We, human being, have survived and prosperd in a biological systems and an immute system plays a significant roll in protecting us against foregin bacillus. From the results of the study field in information processing, it is pointed out that the immute system is capable of learning, memory, pattern recognition and optimization using genetic operators. In the optimization of mechanical and structural designs, an environment of products is significant factor to decide the design. In this study, we will treate the design variables in the optimization problem as antibody and the environment as the antigen. We treated simple numerical examples and they resulted the design stored in memory-cell with best evaluation and worst evaluation considering environment. We have confirmed that the design canditates including the design obtained by mathematical programming are found among the results.

    CiNii

  • Collaborative Optimization in Structural Design using Trade-Off Satisficing Method

    Proc. of MCDM/MCDM   (104)  2000.07

  • Collaborative Optimization in Structural Design using Trade-Off Satisficing Method

    Abstract of 15th MCDM Conf.    2000.07

  • A Study on the Collaborative Design using Supervisor System

    Trans. of JSME Series C/JSME   66-643C (921-928)  2000.03

  • A Study on Multi-Objective Optimization using Supervise System

    MPS Symposium/IPSJ   (165-172)  2000.03

  • スーパバイズシステムによる多目的最適化に関する研究

    情報処理学会 MPSシンポジウム 講演論文集/情報処理学会   No.99-27  2000.03

  • スーパバイズシステムを用いた協調設計に関する研究

    日本機械学会 論文集/日本機械学会   66-643C  2000.03

  • A Study on the Optimum Design Applying Multi-Agents Architecture

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    Transactions of the Japan Society of Mechanical Engineers. C   65 ( 640 ) 4589 - 4596  1999.12

     View Summary

    In recent years, multi-agent architectures which have been studied in the field of artificial intelligence might attract a great deal of attention to the ability of the cooperative properties for engineering. In this study, we proposed a new approach to find the improved design in the layout design and shape design problems of framed structures by applying the multi-agent architectures. We considered each agent as an element in Finite Element Analysis and proposed modification rules for the layout shape of the structure. Following this approach, each agent proposes modification plans based on his or her evaluate function. The proposed plans are picked up or rejected by communication among agents and the remained plans may improve a design created from an initially simple structure. We developed the simulation system running on the UNIX and considerations have been given to the simple truss structural design and some advantages of the proposed have been shown and confirmed.

    CiNii

  • A Study on the Optimum Design Applying Multi-Agents architecture

    Trans of JSME Series C/JSME   65-641C (4589-4596)  1999.12

  • マルチエージェントによる最適設計に関する研究

    日本機械学会 論文集/日本機械学会   65-641C  1999.12

  • Function of Gene in Adaptive Range Genetic Algorithms

    Proc. of CJK-OSM1/JSME,KSME   (141-148)  1999.11  [Refereed]

  • A Study on the Collaborative Optimization Using a Supervisor System

    Proc. of CJK-OSM1/JSME,KSME   (501-508)  1999.11

  • A Study on the Collaborative Design using Supervise Agents

    Proc. of Design Eng. and System Conf./JSME   No.99-27(134-137)  1999.11

  • An Examination and Development of Multidisciplinary Design System

    Proc. of Design Eng. and System Conf./JSME   No.99-27(142-145)  1999.11

  • 複合領域設計システムの構築と検討

    日本機械学会 講演論文集/日本機械学会   No.99-27  1999.11

  • スーパバイズエージェントによる協調設計に関する研究

    日本機械学会 講演論文集/日本機械学会   No.99-27  1999.11

  • A Study on the Collaborative Optimization using a Supervisor System

    第1回 構造最適化に関するシンポジウム論文集/日本機械学会他   Vol.1  1999.11

  • Function of Gene in Adaptive Range Genetic Algorithms

    第1回 構造最適化に関するシンポジウム論文集/日本機械学会他   Vol.1  1999.11  [Refereed]

  • An Examination on the Optimum Design by Search Agents With Multi-Start Search Strategy

    JSME Mechanical Engineering Congress /JSME   No.00-01 (555-556)  1999.07

  • An Examination on the Multidisciplinary Design Optimization System

    Proc. of Design Symp./JSME   (69-76)  1999.07

  • 複合領域最適化における設計支援システムに関する検討

    設計シンポジウム99講演論文集/設計工学会他    1999.07

  • 多点同時探索戦略を用いた検索エージェントによる最適設計に関する研究

    日本機械学会 講演論文集/日本機械学会   No.99-1  1999.07

  • A Study on the Optimum Design Applying Multi-Agent architecture

    Proc. of World Congress of Struct. and Multidisciplinary Opt./ISSMO   Vol.1 (578-580 and CD-ROM)  1999.05

  • A Study on the Optimum Design Applying Multi-Agent architecture

    Proc. of World Congress of Struct. and Multidisciplinary Opt./ISSMO   Vol.1 (578-580 and CD-ROM)  1999.05

  • A Study on the Optimum Design Using Symbolic Manipulation System

    Miyashita Tomoyuki, Yamakawa Hiroshi

    Transactions of the Japan Society of Mechanical Engineers. C   57 ( 541 ) 2959 - 2964  1991.09

     View Summary

    In conventional optimum design process, symbolic formulation of mathematical optimization problem usually must be done by the designers before numerical computation. And these pre-process tasks are sometimes tremendously hard and time consuming for the designers. In this paper, we will show a simplification of these pre-process tasks with an aid of symbolic manjpulation systems which have been studied in the field of Artificial Intelligence. In almost existent symbolic manipulation systems, their main purposes being stressed on verifying the expression, the computer programs in the systems could not obtain any information directly from the operator during the excuting of the program. In this study, to reduce this disadvantage we use menu system as interactive computer system to define and decide the objective function and constraints freely. And, we applied a symbolic manupulation system to a formulation of the objective function and the constraints as well as to structural analysis by Energy method. Consideration have been given to the obtained optimum designs and the effectiveness was confirmed.

    CiNii

  • 数式処理システムを用いた最適設計に関する研究

    Tomoyuki MIYASHITA, Hiroshi YAMAKAWA

    日本機械学会 論文集C編   57-541C   2959 - 2964  1991.03  [Refereed]

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Books and Other Publications

  • Engineering Design

    G. Pahl, W. Beitz, J. Feldhusen, K.H. Grote

    Morikita Publishing  2015.02

  • 最適化ハンドブック

    最適化ハンドブック

    朝倉書店  2003.03

Industrial Property Rights

  • 冷却器、半導体モジュール

    宮下 朋之, 立石 義博, 沼田 俊介

    Patent

  • 冷却器

    宮下 朋之, 立石 義博

    Patent

  • 遠隔操作用入力システム及び手首動作検出装置

    三浦 智, 上原 瑠哉, 菅野 重樹, 藤江 正克, 宮下 朋之

    Patent

  • 展開型車輪及びこれを利用した走行装置

    宮下 朋之, 江口 航平, 三浦 智

    Patent

Awards

  • IEEE ISATP2003 Best Paper Award

    2003.07  

  • JSCES Encouragement

    2003.05  

Research Projects

  • ヒトの身体性に柔軟に協調するインタフェースの制御手法の構築

    Project Year :

    2020.04
    -
    2023.03
     

  • Research on simultaneous optimization method of radio wave and large membrane space structure to construct communication system

    Project Year :

    2018.04
    -
    2021.03
     

  • Development of Additive manufacturing for large space structure

    Project Year :

    2017.06
    -
    2019.03
     

     View Summary

    Large space structures generally have a part-like assembly procedure due to the limitations of vehicles such as rockets. However, by enabling transportation in a flexible manner in a state where the shape suitable for transportation of powder, liquid, etc. can be changed, and stiffening in space, construction of a large space structure becomes efficien. In this research, for the purpose of constructing powder molding technology in space, create a structure in an environment where thermal load is applied in vacuum using polyetherimide which is a kind of conductive material and super engineering plastic. Demonstrated and examined. About 10% improvement in strength was seen by producing in space environment

  • Novel Stowed Strategy by Spiral Folding Lines for Curved Membrane and its Deployment Properties

    Project Year :

    2016.04
    -
    2018.03
     

     View Summary

    Several initiatives were implemented on the storage technology of the membrane surface of the curved surface shape proposed by the applicant. (1) We examined the use and storage method as antenna for parabolic shape. (2) Utilizing the characteristics of handling the film thickness as variable, we realized the storage technology considering the existence of the parts on the surface. In addition, the panel shape can be accommodated by considering the thickness. We developed a new method to apply the Miura folding technique to the plate structure. (3) The development behavior of the stored membrane surface was realized considering a mechanical properties as a numerical simulation. (4) A storage technique combining spiral folding and bellows folding was mathematically formulated with respect to the plane surface and curved surface, and verified by experiment. (5) As a new use, application to adhesive plaster, air bag, etc. was studied

  • A Thermal Control Method for Supporting Thermal Therapy based on the Precise Bio-heat Transfer Model and Electromagnetism Model

    Project Year :

    2013.04
    -
    2015.03
     

     View Summary

    Radio frequency ablation treatment has become the most popular thermal therapy in Japan. We aim to improve the accuracy of the radio frequency ablation so that we developed an ablation supporting system based on the accurate bio-heat transfer model and electromagnetism model. We employed the model-based control method to construct the numerical analysis method and electric current control actuator minimal invasively, which can adjust the electric volume based on the bio-heat transfer model to calculate the temperature distribution of tissue. In addition our proposed system was evaluated in both in vitro and in vivo experiments. Both of the experimental results showed our proposed system is possible to ablate tissue reaching the desired temperature, which was viewed suspicion by medical reports. Thus, our proposed method will contribute to improve the ablation supporting system and realize a much more accuracy thermal therapy in future

  • Development of a Soft Clothes-type Robot with Easiness to Wear

    Project Year :

    2012.04
    -
    2014.03
     

     View Summary

    Recently, in the super-aged society in Japan, exoskeletons are developed in many ways to support works and activities of elderly people. However, in present, exoskeletons are used in particular situation even though in rehabilitation field because process to put on exoskeletons takes long time, uncomfortableness to wear, and high cost. In this research, we tried to develop a clothes-type robot to ease the process to put on it and to comfort wearing. The clothes-type robot includes shape memory alloy (SMA) actuator to support lifting up the host's lower limb. We set a movement to climb stairs by paralyzed patients as a target, and tried to develop hardware and software

  • Development for radio frequency ablation supporting system appropriate to coagulation area of tumor by clarifying coagulation mechanism

    Project Year :

    2011.05
    -
    2014.03
     

     View Summary

    In order to provide the accuracy of radio frequency ablation (RFA) treatment we proposed a RFA supporting treatment system. We mainly focused on the problems of RFA treatment and proposed the solutions such as (1) clarify the mechanism of coagulation in RFA and (2) develop the temperature distribution simulator based coagulation condition. We employed both mechanical method and biology method to make analyze the coagulation condition and evaluate the experimental results. According to the in vitro experiments, we found that the viscoelasticity of tissue in RFA treatment was useful as the index of coagulation condition and modeled the temperature dependence of viscoelasticity. And we used both mechanical method and biology method to derive and evaluate the parameters of ablation condition, which determined the coagulation condition of tissue. We also validated the bio-heat transfer model in RFA and developed the temperature distribution numerical simulator for RFA

  • Development of Accistance System for High Accuracy Breast Cancer Radio Frequency Ablation

    Project Year :

    2010.04
    -
    2013.03
     

     View Summary

    Recently the radio frequency ablation (RFA) treatment is focused on as minimally invasive treatment for breast cancer. In order to improve treatment effect of RFA, we developed the support system of RFA treatment for breast cancer ablation high accurately. Our system mainly consists of high accuracy temperature distribution simulator and optimal process for puncture. As the results of some in vivo experiments, the temperature distribution simulator enable to be high repeatability that the temperature difference between experimental results and analysis results is within 4.0 deg C. And, in obtaining the process of optimal puncture for breast cancer, we developed the optimal puncture condition. This condition was derived from in vitro experiments by using simulant cancer which was implanted in hog breast

  • A Study on Integrated Design System using Multi-Agents System

     View Summary

    In this study, we discussed advantages of the proposed methods to integrate the complicated mechanical systems using multi-agents technology that is public attention in the study field of artificial intelligence. In 1999, firstly, we have investigated the multi-agents technology in detail. Then we propose the new collaboration methods and developed the system that can work on computer network. The developed system has the component that can integrate commercial analysis software. From the discussion of the application, we discussed the design of robot manipulator considering dynamic and static properties. In 2000, we have integrated the results obtained in previous year and examined the effectiveness of the proposed method and developed system. It is important to offer the designers the information for compromise and possible to contribute with the formulation of collaboration, especially, in the case that there exists the conflicts among objective functions. It is also recognized that the developed system can treat the design of mechanism, structural design, design of orbit and design of control system using commercial software integrated in the developed system. The designs obtained from the developed system are developed as the experimental facilitate and experimentally confirmed the advantages of the performances. We discussed the results obtained from numerical analysis and experimental analysis and confirmed the advantaged of the proposed methods. We recognized that future works are necessary because the problems treated in this study are important and difficult in the case including some economical features. Then we have stated the future works as follows. (1) The design stages including technical fields and economical fields should be considered especially in the case of early design stages. (2) The performances and design variables are not decided in the case of early design stages. Then, it is important to be considered the modification of the design problems easily

  • Acceleration of Geometric Computations in CAD and CAM by Using Polygon Rendering Hardware

     View Summary

    In order to follow frequently changing customer preferences and to quickly distribute products with high market competitiveness, Japanese manufacturing companies make efforts to shorten the production preparation time after the design completion. Most time period of the production preparation is consumed for making dies and molds for stamping, casting and plastic molding of parts. Dies and molds are usually fabricated using 3-axis numerically controlled (NC) milling machines with various shape cutters. Computation of the reliable cutter path is still a difficult problem. Several hours are often needed for computing whole cutter paths for milling a complex die. Members in this project jointly develop a new technology for fast generation and verification of the cutter path for NC milling. Our technology uses graphics processing unit (GPU) which is currently equipped in most computers, for accelerating the geometric computation in process planning, NC path generation and path verification. As the result of the project, the following technologies are realized ; (1) a practical GPU accelerated CAM system is developed. This system is currently running as a kernel system of one Japanese automobile manufacturer, (2) an algorithm for projecting the machining remained area in a prior machining to the cutter location surface for the next machining is proposed. This projection is useful for automating some process planning task of mold machining, (3) some GPU accelerated algorithms for defining the curved surface and evaluating its geometric quality are developed, (4) several algorithms for accelerating geometric computations in non-manufacturing fields are developed also. Proposed algorithms are implemented and an experimental CAD/CAM/CAPP programs using this technology are demonstrated

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Presentations

  • 伸展マスト構造でのサーマルスナップ現象における摩擦特性に関する研究

    清水駿之介, 石村康生, 宮下朋之

    第62回宇宙科学技術連合講演会 

    Presentation date: 2018.10

  • 多重らせん折り膜面に関する研究

    須崎航, 宮下朋之, 名取通弘

    第62回宇宙科学技術連合講演会 

    Presentation date: 2018.10

  • Benchmarking Deep Learning Models on Prosthetic Hand State Recognition

    MIYASHITA, Tomoyuki

    Presentation date: 2018.09

  • 月面洞窟内のサンプル採取を目指したパラメータ励振による振動制御に関する研究

    三浦智, 熊井雅人, Parque Victor, 宮下朋之

    日本機械学会ロボティクス・メカトロニクス講演会(ROBOMECH2018) 

    Presentation date: 2018.06

  • カテーテル伸展システムの直感的操作に関する研究

    浜島基, 三浦智, Parque Victor, 宮下朋之

    日本機械学会ロボティクス・メカトロニクス講演会(ROBOMECH2019) 

    Presentation date: 2018.06

  • 階層モジュラー型宇宙構造物の自己構築システムに関する研究

    長谷川翔一, 三浦智, Parque Victor, 宮下朋之

    日本機械学会ロボティクス・メカトロニクス講演会(ROBOMECH2020) 

    Presentation date: 2018.06

  • 構造物の位相最適化における荷重伝達指標Ustar (U*)の適用,(1) 荷重伝達指標Ustar (U*) を考慮したレベルセット法

    宮下 朋之

    日本機械学会 IIP2018 情報・知能・精密機器部門(IIP 部門)講演会 

    Presentation date: 2018.03

  • 構造物の位相最適化における荷重伝達指標 Ustar (U*)の適用 (2) 荷重伝達U*エントロピーによる経路の明瞭化

    宮下 朋之

    日本機械学会 IIP2018 情報・知能・精密機器部門(IIP 部門)講演会 

    Presentation date: 2018.03

  • キネマチックカップリングにおける熱変形時の境界面の滑りについて

    宮下 朋之

    宇宙構造材料シンポジウム 

    Presentation date: 2017.12

  • 月面ローバ車輪の走破性の設計と検証

    江口航平, 宮下朋之

    第61回宇宙科学技術連合講演会講演集 

    Presentation date: 2017.10

  • 伸展マスト構造でのサーマルスナップ現象における摩擦特性の影響

    清水駿之介, 浅沼範大, 山川宏, 宮下朋之

    第61回宇宙科学技術連合講演会 

    Presentation date: 2017.10

  • 荷重伝達指標Ustar(U*)を用いた位相最適化

    宮下 朋之

    日本設計工学会2017年度秋季大会研究発表講演会 

    Presentation date: 2017.10

  • 痙縮の発症した片麻痺患者用の円筒型タイピング支援装置の開発

    杉原 壮一郎, 三浦 智, 宮下 朋之

    生活生命支援医療福祉工学系学会連合大会講演要旨集 

    Presentation date: 2017.09

  • 伸展式架台の軌道上におけるサーマルスナップの低減に関する研究

    浅沼範大, 宮下朋之

    構造強度に関する講演会 

    Presentation date: 2017.08

  • Optimization of the upper arm cuff applied the compliant mechanism for holding the forearm artificial arm

    Victor Parque

    Trans. jpn. Soc. Med. Bio. Eng 

    Presentation date: 2017

     View Summary

    <p>For holding the forearm artificial arm, the patient must pull and tighten a part of the belt. However, the pressure distribution becomes heterogeneous so that the patient could become the bedsore. In this paper, our motivation is to develop the upper arm cuff that can distribute the even pressure. We optimized the upper arm cuff design applied the compliant mechanism and compare with the conventional design to validate the feasibility study of the proposed design. We optimized the upper arm cuff based on the Dr. Kanno's design as the initial shape. In experiment, we measured the displacement of the structure. As a result, we identified the consistency between the experimental value and the optimized solution. Then, we measured the internal pressure using a variation index. We concluded that the compliant mechanism design could decrease the pressure dispersion more significantly than conventional design.</p>

  • On Path Planning using Log-Aesthetic Curves

    Parque Victor, Kobayashi Masakazu, Miyashita Tomoyuki, Higashi Masatake

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2017

     View Summary

    Path planning with safety considerations regards the minimization of the (variation) of curvature along the curved path. We present for the first time the application of log-aesthetic curves in path planning. Our results show the feasibility and the computational efficiency compared to the conventional methods.

  • On Route Bundling in Triangulated Space

    Parque Victor, Kobayashi Masakazu, Miyashita Tomoyuki

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2017

     View Summary

    Route bundling consists of compounding multiple paths into a single route by finding optimal anchoring points at intermediate joints, which serve as coordinating locus for joint transport of goods/people. Route bundling is a significant construct in a number of planning scenarios where transport resource is scarce. We present the problem of route bundling and propose a new method for finding such compounded routes. Computational experiments in scenarios with/without obstacles show the feasibility and efficiency of our approach.

  • Measurement of forearm&rsquo;s viscoelastic distribution for tremor suppression robot design

    Kawasaki Motoji, Tsukune Mariko, Matsumoto Yuya, Seki Masatoshi, Kobayashi Yo, Miyashita Tomoyuki, Fujie Masakatsu G

    JNSE 

    Presentation date: 2016

     View Summary

    &emsp; We focused on viscoelasticity of soft biological tissue as a quantitative index to design a wearable tremor suppressing robot frame with high suppression capability. We propose a design method for the robot frame that select parts having high viscosity in the forearm as positions where the robot frame is attached, because high viscosity have the potential to suppress tremor. In this research, we use phase shift between displacement and reaction force from the soft biological tissue as an indicator of viscoelasticity based on forced oscillation model of soft biological tissue by tremor, and investigate the viscoelasticity distribution on a palm side of the forearm in three younger subjects. Additionally, we observed the correlation of the distribution between the subjects and the anatomical features with an ultrasonograph. As a result, proximal part from the elbow with thick aponeurosis had resembled distribution and showed minimum phase shift of 2.03[°], therefore this part is not suitable for suppressing. Distal part from the elbow showed maximum phase shift of 10.9[°], therefore this part is suitable for suppressing, but showed individual distribution. We will develop the individualized design method of the robot frame using these results.

  • A study on optimization of vehicle structure using market data

    HONOBE Kazuhiro, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2016

     View Summary

    <p>In this research, we proposed a process in which criteria was built by Data Envelopment Analysis with vehicle data on the market. Using DEA, we derived a one-dimensional evaluation value from a multi-dimensional index. However, DEA has flexibility in evaluation model. So we constructed it with Interpretive Structural Modeling. ISM is the method to clarify relationship between items with paired comparison and create a hierarchical structure chart. As a result, we made 32 evaluation models and determine the best model which has the maximum standard deviation. This enabled us to eliminate the intention of the user. In addition, we obtained some features of the evaluation result. For example, it was difficult for vehicle data which has better fuel efficiency to acquire a high evaluation. Larger or smaller displacement vehicle obtained higher evaluation value, and middle class vehicle obtained middle value widely. In addition, we optimized the value of each evaluation item and obtained proposition for design, which was derived from data of 108 new vehicles and proposed larger or smaller displacement and shape. From the above, we confirm that DEA is useful for evaluating products and ISM is efficiency for constructing the evaluation model of DEA.</p>

  • Study on Error of Posture in the Arm Tip Using Brain Activity Measurement

    MIURA Satoshi, KAWAMURA Kazuya, KOBAYASHI Yo, MIYASHITA Tomoyuki, G. FUJIE Masakatsu

    Robomech 

    Presentation date: 2016

     View Summary

    <p>This paper presents a novel evaluation method for an intuitive operability of master-slave surgical robot. Surgical robot is controlled to match the posture of the arm tip between master-slave, however, it's impossible to match the posture because strict sensing is difficult and the error accumulates during manipulation. The objective is to validate the change of the brain activation against the change of error of posture in the arm tip. In experiment, participants controlled the virtual master-slave simulation. As a result, the brain activity decreased when the error of posture in the arm tip increased. The paper concluded that the 30° would be the acceptable error because when the error was smaller than 30° , the brain activated same as he relaxed.</p>

  • A Design of Automobile Structure Considering Impact Response Considering Load Transfer Path

    Morisaki Yohei, Miyashita Tomoyuki

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2015

     View Summary

    本研究では自動車の車体構造を対象に, U* と Transfer Path Analysis と呼ばれる2つの手法を適用し,線形領域と非線形領域の両方で衝撃荷重が入力された際に生じる荷重の伝達経路を明確化することで両手法の評価を行った.さらに,モーターサイクルの車体構造に両手法を適用することで設計改善を実施し,衝撃入力時に乗車位置に生じる加速度の10%程度の低減を得た.

  • Evaluation of heat and dynamic characteristics on contact surface between the parts

    Sato Toru, Miyashita Tomoyuki

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2015

     View Summary

    部品間の接触部への粘弾性体の挿入はプラント配管や自動車などの輸送機器といった多くの製品に行われている.本研究ではフィルム・グリス挿入に対してそれらの最適配置の検討を目指して熱・振動特性の評価を行った.モデルとして立方モデルを扱い,接触変化状況やボルト締結による影響を実験・解析により取得し,温度が増大する条件を提示した.また,振動に関して振動応答を低減するフィルム・グリス配置を示した.

  • 1A1-E06 Measurement of relationship between tissue deformations and penetration force for membrane suture supporting system

    SAKAKIBARA Kotaro, TSUKINE Mariko, KOBAYASHI Yo, MIYASHITA Tomoyuki, FUJIE Masakatsu G

    Robomech 

    Presentation date: 2015

     View Summary

    Recently, surgical robot is used in biliary-pancreatic surgery. However, complications, such as failure of the sutures, occur frequently. Therefore, we propose a membrane suture supporting system that prevent from unintentional needle penetration that cause failure of the sutures. Our strategy is that predict the ease of needle penetration through membrane from strain of that. We investigated relationship between strain of tissue isolated from porcine jejunum and penetration force by needle insertion experiment. As a result, the following relationship was suggested; when the strain increased at a constant rate of change, the penetration force became constant, however when the strain exceeded a certain value with the tension, the growth rate of the strain decreased, and the penetration force decreased.

  • 1A1-C09 Development for Radio Frequency Ablation Supporting System : Derivation for Model-based Control based on Ablation Condition

    LU Xiaowei, ISOBE Yosuke, KOBAYASHI Yo, MIYASHITA Tomoyuki, FUJIE Masakatsu G

    Robomech 

    Presentation date: 2015

     View Summary

    While liver RFA treatment is minimally invasive, it is difficult for surgeon to confirm the ablated area on ultrasonic image. For accuracy improvement of RFA treatment we proposed an ablation supporting system for RFA. In this paper we discussed how the time interval affects the accuracy and analysis cost in the system. According to the experimental results under different time interval conditions it is suggested the time interval 30[s] was efficient to realize the goal temperature of the certain location close to the needle.

  • 2211 A study on optimization of vehicle structure using market data

    HONOBE Kazuhiro, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2015

     View Summary

    In this research, we proposed a criteria development process treating about 23000 vehicle data which were published on the market from 1982 to 2013 years by Data Envelopment Analysis. DEA is the method for obtaining an evaluation with multidimensional index. However, it is necessary to determine the evaluation model. So we constructed it by Interpretive Structural Modeling. ISM builds a hierarchical structure from paired comparison, and clarifies the relationship between items. As a result, we derived 32 evaluation models from ISM and decided the best model based on the standard deviation to be maximized. This makes it possible to avoid the arbitrariness of the user. In the best model, vehicle data which have lower fuel efficiency obtain higher comprehensive evaluation value. Otherwise, in displacement and price, minimum comprehensive evaluation value is in the middle, vehicle data which has lower and higher evaluation item value obtain higher comprehensive evaluation value. In addition, we optimized the value of each evaluation item for vehicle type and obtained proposition for design for each type, which proposed smaller displacement and shape. From the above, we confirm that DEA is useful for evaluating products and ISM is efficiency for constructing the evaluation model of DEA.

  • Effects of temperature on orbit by thermal contact resistance with bolted joints of nano-satllite

    佐藤 融, 宮下 朋之

    宇宙科学技術連合講演会講演集 

    Presentation date: 2014.11

  • Development of Parabolic Folding Patterns Considering Their Thickness Effects

    粉川 靖之, 宮下 朋之, 名取 通弘

    宇宙科学技術連合講演会講演集 

    Presentation date: 2014.11

  • A study on GPU-based Topology Optimization

    KAMEZAKI Hiroki, MIYASHITA Tomoyuki

    The Computational Mechanics Conference 

    Presentation date: 2014.11

  • A Design of Automobile Structure considering Crashworthiness by Load Transfer Path

    MORISAKI Yohei, MIYASHITA Tomoyuki

    The Computational Mechanics Conference 

    Presentation date: 2014.11

  • 結合剛性を考慮したスペースフレーム構造を有する車両の最適化に関する研究

    森崎 陽平, 宮下 朋之

    精密工学会学術講演会講演論文集 

    Presentation date: 2014

     View Summary

    中空鋼管で構成されるスペースフレーム構造である競技用車両について,剛性の最大化を目的として最適化を行う.実際の溶接部による基礎実験で得た要素間の結合剛性を考慮する結合要素により,梁要素を結合した有限モデルを作成した.作成したモデルを用い,レギュレーション等の設計要件を満たしつつ剛性が最大となる要素配置を遺伝的アルゴリズムにより検討し,定常円旋回を模擬した荷重に対して最大変位部の変位が約15%減少した.

  • J2410105 Modeling of Heat Generation Value based on Electrical Impedance Frequency Characteristic under Radio-Frequency Ablation

    Yamazaki Nozomu, Kobayashi Yo, Kikuchi Hayato, Lu Xiao Wei, Kusaka Jin, Miyashita Tomoyuki, Fujie Masakatsu G

    The Proceedings of Mechanical Engineering Congress, Japan 

    Presentation date: 2014

     View Summary

    Radio Frequency Ablation (RFA) is one kinds of hyperthermia treatment for cancer. Advantages of RFA are mainly low impact operations and shorter hospital stay. Disadvantage of RFA is difficult to get coagulation information for operator. Therefore, it needs to control ablation energy precisely. Thus, we have been proposed a method control of ablation energy. A feature of RFA, it uses electromagnetic-wave for ablation. RFA is related as not only thermal physics but also electrical physics. And, Heat generation from RF-electrode depends on frequency of electromagnetic-wave frequency. Therefore, in this study, we modeled heat generation based on electric impedance frequency characteristic during RFA. Firstly, it measured electric impedance frequency characteristic of pig liver samples. Secondly, it measured temperature distribution of the samples during RFA. Finally, it modeled electric impedance frequency characteristic of pig liver samples based on equivalent circuit model which was considered about fractional calculus. And, we evaluated a value of electrical impedance. From results, Model value of heat generation was matched with actual measurement value by using a coefficient of electrical impedance.

  • Design and performance evaluation on a deployable membrane mechanism for a nano satellite

    粉川 靖之, 宮下 朋之, 名取 通弘

    宇宙科学技術連合講演会講演集 

    Presentation date: 2013.10

  • A study on prediction of temperature on orbit of nano-satellite considering thermal contact resistance between the parts

    佐藤 融, 宮下 朋之

    宇宙科学技術連合講演会講演集 

    Presentation date: 2013.10

  • 2803 A study on GPU-based FEM analysis of 3-D unsteady heat transfer of sintered metal

    KAMEZAKI Hiroki, MIYASHITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2013

  • 408 A study on the estimation of passenger's behavior under a train collision

    TAKAHASHI Shuhei, TANAKA Yusuke, MIYASHITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2013

  • J164034 Investigation of the Flow Dependence of Heat Transfer Coefficient in Great Vessel for Radio Frequency Ablation

    KIKUCHI Hayato, ISOBE Yosuke, Lu Xiaowei, YAMAZAKI Nozomu, WATANABE Hiroki, KOBAYASHI Yo, MIYASHITA Tomoyuki, FUJIE Masakatsu

    The Proceedings of Mechanical Engineering Congress, Japan 

    Presentation date: 2013

     View Summary

    Radio frequency ablation (RFA) is one of the minimally invasive and useful treatments for liver cancer. While RFA is popular approach for liver cancer in Japan, RFA has several disadvantages such as ablation temperature is excess or insufficient. Because flow in great vessels absorbs the heat from electrode needle in liver RFA, it is difficult for surgeon to estimate the temperature distribution. In this study, we used the experimental system with porcine great vessels and porcine liver to investigate about the relationship between heat loss and flow volume in great vessels. We calculated the heat transfer coefficient based on Newton's law of cooling under each flow volume in each great vessel, and figured out the relationship between heat transfer coefficient and flow volume. As a result, heat transfer coefficient depends on flow volume in great vessels. And the relationship between heat transfer coefficient and flow volume is linearity. These results suggested that the relationship between flow volume in blood vessel and heat transfer coefficient is linearity, and flow volume in blood vessel causes heat loss in RFA.

  • 3308 A study on the design of scaled impact dummy with optimization methods and similarity rule

    TAKAHASHI Shuhei, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2013

     View Summary

    Scaled dummy used in the experiment on the estimation of passenger's behavior under a train collision is designed considering a similarity rule. Several tests are applied to evaluate dummy biofidelity according to ISO technicalreport ISO/TR9790. Overall biofidelity of the dummy is 4.62 points out of 10. And it is the third-highest rating "Fair Biofidelity" out of 5 ratings indicating the degree of biofidelity. Next, Finite element is applied conducted to improve thoraxbiofidelity dummy using optimization method, suchas breadth of rib, thickness of soft tissue and Elastic Modulus of soft tissue because response on thoraximpact test is particularly bad. Optimized dummy is developed and thoraximpact test is conducted again. The maximum value of impactor force of optimized dummy is 28.1% better than that of unoptimized one.

  • 3307 A Study on Concept Design Support Using Data Envelopment Analysis

    TAKAHASHI Masafumi, MIYASITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2013

     View Summary

    In the stage of a conceptual design, designers often stimulate and influence each other, and they must conceive a completely new idea and the outstanding idea. However, as a design problem, it is dependent on a designer's experience and intuition. Furthermore, the suggestion of an idea is sometimes plentifully performed by two or more persons, sharing of mutual knowledge or information for a smooth communication. Therefore, it is necessary to establish the reasonable design method to derive excellent idea, in this study, the new design approach which combined two design methods of an axiomatic design theory and TRIZ is proposed, the validity of a design method is confirmed. The axiomatic design theory clarifies the process in a design TRIZ offers the solution of a design which a designer didn't know. By combining these advantages, we will proposed a new method. The experiment using the proposed methods, technique nothing, TRIZ, the axiomatic design theory, and the TRIZ+ axiomatic design theory. And, it is verified what kind of difference the number of ideas or quality. As a result, TRIZ was able to conceive many ideas, but quality is inferior to other design methods. The axiomatic design theory could conceive the high quality idea, but a number of ideas are inferior to other design methods. Although the TRIZ+ axiomatic design theory had few ideas, the highest quality idea was able to be conceived.

  • 1112 A Study of Design of Shock Absorption Mechanisms Using Compliant Mechanisms

    NAKAMURA Yuta, HATTORI Yuta, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2013

     View Summary

    In this study, we try to design a shock absorbing structure using the compliant mechanism. To design the shock absorbing structure, it is necessary to consider the plastic deformation. We use the elastic-plastic body to design the compliant mechanism. First, we do topology optimization whose object function is to design the shock absorbing structure and the compliant mechanism. In this topology optimization, we use Evolutionary Structual Optimization. And we investigate the shape and the characteristic while the parameters fluctuation. Secondly, the impact test is done to confirm whether it is functioning as a shock absorbing structure. We test two models and compare the behavior of each model.

  • 3407 Experimental study of seating type and passenger behavior in railway vehicle collision

    MATSUDA Atsushi, MIYASHITA Tomoyuki

    Presentation date: 2012.09

     View Summary

    When major train collisions occur, train structure deforms to reduce the impact effect. However, some passengers are injured in spite of the shock absorption of the structure. Therefore, it is necessary to design train structure to reduce injuries of passengers when accidents occur. In this study, we proposed the design improvements strategies to reduce injuries of the passengers caused by train collisions. We experimented with scale-down models of passengers and vehicles. To evaluate injury levels, we used HIC36 as a standard for head injuries. As a result of these experiments, HIC36 is influenced by seating position and type. We proposed three train structures to reduce injuries of passengers. These are that of using convertible seats, seating passengers with their backs to the front of the train and seating passengers in the rear of the vehicle.

  • 2309 Study of Designing Shock Absorption Mechanisms Using Compliant Mechanisms

    OKADA Kenta, MIYASHITA Tomoyuki

    Presentation date: 2012.09

     View Summary

    In this study, to design a shock absorbing structure using the compliant mechanism. To be applied to the shock absorbing structure is necessary to consider the plastic deformation. However, in previous studies such research has not been done. In the present study to design a compliant mechanism targets the elasto-plastic body. And this mechanism is applied to impact-absorbing structure. First we use topology optimization whose object function is to design shock absorbing structure and compliant mechanism. And we can design model which has compliant mechanism and shock absorbing function. Secondly impact test is performed using this mechanism. We create a model for comparison for this test. We compare the behavior of each model and discuss about it.

  • 2208 A study on minimization of weight for satellite considering component location

    MIZUMACHI Seiya, MIYASHITA Tomoyuki

    Presentation date: 2012.09

     View Summary

    Recently the development of the nano satellite becomes active. In general, nano satellites are expected to be developed faster and cheaper than the large satellites. The launching cost of the piggyback satellite is reasonable, and then a cost of a piggyback satellite is often decided by weight. Therefore it is important to reduce the weight of satellite for cost. We have to design of satellite structure considering the severe mechanical environment of launching. The natural frequency of the satellite should be higher than the value decided by the rocket and the satellite should withstand the loads during launch. In addition, harnesses are also important component when we design satellites. In this paper, we will propose the design of the satellite whose dimension is 400 millimeters cube. The satellite supposed to be launched by H-2A rocket and we focused on the trade-off design between minimization of mass and maximization of natural frequency under the maximum stress condition for optimizing the satellite structures.

  • J165034 Development of Robotic Palpation System to Measure the Nonlinear Elasticity for Breast Cancer Diagnosis Support : Consideration of Compression Method Using Two Indenters by Finite Element Analysis

    TSUKUNE Mariko, KOBAYASHI Yo, MIYASHITA Tomoyuki, SHIRAISHI Yasuyuki, YAMBE Tomoyuki, HASHIZUME Makoto, FUJIE Masakatsu

    The Proceedings of Mechanical Engineering Congress, Japan 

    Presentation date: 2012

     View Summary

    A disadvantage of nonlinear elastography techniques for breast tumor diagnosis is that the tumor does not strain sufficiently to observe nonlinear elasticity We propose a robotic palpation system with two indenters to evaluate the nonlinear elasticity properties of tissues The objective of the present study was to consider a compression method in terms of the position of indenters and the section area of indenters to generate large strain in tumors by finite element analysis As a result, it was found that the following compression conditions made tumor deformable First condition is that the default position of indenter is located near the tumor Second condition is that the section area of indenters is enlarged if the default position of indenter is located near the tumor, and the section area of indenters is made smaller if the default position of indenter is distance from the tumor

  • 2208 A study on optimization of Shock absorbing structures as Compliant Mechanisms

    HATTORI Yuta, MIYASHITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2012

  • 2A2-S09 Investigation into mechanism of electrode needle which allows generating asymmetric ablation shape in RFA(Surgical Robotics and Mechatronics (1))

    ISOBE Yosuke, YAMAZAKI Nozomu, WATANABE Hiroki, KOBAYASHI Yo, MIYASHITA Tomoyuki, OHDAIRA Takeshi, HASHIZUME Makoto, FUJIE Masakatsu G

    Robomech 

    Presentation date: 2012

     View Summary

    RFA is a treatment modality for cancer that is becoming accepted because of its less-invasiveness and high-curability. Controlling the shape of ablation area increases curative effect. Therefore we propose the mechanism of electrode needle that RF current flow between two secondary electrode needles. We examined the parameters required to obtain a trapezoidal ablation area surrounded by two electrode needles. The result of simulation, it was suggested that the relation of length and thickness of two needles affect ablation. In addition, we performed ablation experiments using agar phantoms. We evaluated the ablation shape of simulation and experiment as three-dimensional cube set. Then, we confirmed that result of simulation and experiments were in agreement.

  • 2P1-C08 Measuring the nonlinear elastic properties of breast tissue components and comparison of measurement results(Medical Robotics and Mechatronics)

    TSUKUNE Mariko, KOBAYASHI Yo, HOSHI Takeharu, MIYASHITA Tomoyuki, FUJIE Masakatsu G

    Robomech 

    Presentation date: 2011

     View Summary

    As the number of breast cancer patients increases, non- invasive and accuracy diagnosis of breast cancer is required. It is expected that there is diagnostic potential in examining the nonlinear elastic properties of soft tissues. The measurement method of the nonlinear elasticity of tumor in breast is needed. Therefore, we propose the robotic palpation system for diagnosis based the nonlinear elasticity. Here, we report the measurement of the nonlinear elastic properties of breast tissue components. The nonlinear elastic properties of breast tissue were investigated with a creep test. The three parameters of the nonlinear elastic model were acquired. In conclusion, two of these parameters are significantly different among the components. There was indicated that the magnitude of parameter is determined by tissue structure. There was suggested that the difference in parameter distribution causes the difference in dynamic response of breast tissue.

  • 2309 A study on estimation of the deformation behavior in the collapse process of lung

    KATSUYAMA Yusuke, MIYASHITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2011

  • 2002 A study on GPU-based FEM analysis of medical images

    KOBAYASHI Yuta, MIYASHITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2011

  • 3202 A study on minimization of weight for satellite considering component location

    MIZUMACH Seiya, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2011

     View Summary

    Recently the development of the nano satellite becomes active. In general, nano satellites are expected to be developed faster and cheaper than the large satellites. The launching cost of the piggyback satellite is reasonable, and then a cost of a piggyback satellite is often decided by weight. Therefore it is important to reduce the weight of satellite for cost. We have to design of satellite structure considering the severe mechanical environment of launching. The natural frequency of the satellite should be higher than the value decided by the rocket and the satellite should withstand the loads during launch. In this paper, we will propose the design of the satellite whose dimension is 400 millimeters cube. The satellite supposed to be launched by H-II A rocket and we focused on the trade-off design between minimization of mass and maximization of natural frequency under the maximum stress condition for optimizing the satellite structures.

  • 2403 An experimental study on the estimation of passenger's behavior in under a train collision

    TANAKA Yusuke, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2011

     View Summary

    An experiment on the estimation of a large number of passenger's behavior in under a train collision is studied using small train model. Here, we treated the position of passenger paying attention to a seat for seven persons. As a result of the experiment, passenger's head injury is influenced by seating position or coefficient of static friction of floor material. We discussed relation of between seating position or coefficient of static friction of floor material and passenger's head injury, and proposed four ideas reducing damage of passengers.

  • 2101 A Study on Conceptual Design Method Applying Data Envelopment Analysis and TRIZ

    SATO Masaki, HANADA Ryu, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2011

     View Summary

    In conceptual design phase, According paying attention to specific design objectives, designers sometimes avoid to get various ideas about new product. On the other hand, using brainstorming allows to get various ideas, but it causes a problem to obtain a lot of unavailable ideas together. In this study, to support generating various and effective ideas in conceptual design, we propose a conceptual design support method applying Data Envelopment Analysis and TRIZ. We proposed the method using several evaluation values to fill the gap of pareto frontier and creating hierarchy graphs. In this study, we propose the method using TRIZ at the Brain Storming stage in addition to the our proposed method. Various information is given to the designer from hierarchy relation graphically and TRIZ when they conceive new ideas. We verified which technique is effective to obtain new ideas with high evaluation by comparing these two methods. The result shows that the proposed method using TRIZ is more efficient than the other way not using TRIZ.

  • 1501 A research on watch device for packing structure and contents acting impact force

    MIZUNO Tomomasa, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2010

     View Summary

    The corrugated cardboard is widely used for packing in the transportation. Therefore, the technology that minimizes various transportation accidents is necessary. Especially, the accidents by the impact occupies the more than the half of the accidents. There are many researches that evaluates the maximal acceleration of the corrugated cardboard under the impact. However, because the maximal acceleration is not necessarily corresponding to the damage of contents, it is difficult to evaluate the impact of the corrugated cardboard only by the maximal acceleration. Also the place to measure is the center of the ground side but it is not discussed about the measuring place. In this paper, impact force is applied by a free fall test by a guide rail to drop it straight to the ground. The ID acceleration sensor, are glued in several place to make clear the difference between the measured place. From the experiment, we considered impact energy and the maximal acceleration. In addition, we made an analytical model of the corrugated cardboard to analysis to identity the damage. As a result, strain energy has a correspondence between the experiment and the analysis and the maximal acceleration didn't have it. So, the utility of the strain energy was able to be shown as a method of evaluating the impact using FEM. Through this result, we watched how the energy spread and found out the center of the ground side and the wall side has a high energy when it's impacted and when a few second pasts the wall side still has a high energy because of the vibration of the cardboard. To find out the relation between the data from the corrugated cardboard and the contents. As a result, the maximal acceleration has a strong relation between the center of the ground side and the energy has a strong relation between the middle of the center and the corner. Finally, we also considered HIC36 to evaluate the impact.

  • 1201 A Study on Concept Design Support Using Data Envelopment Analysis

    SATO Masaki, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2010

     View Summary

    In conceptual design phase, if designers are much more conscious of design objectives, they won't come up with various ideas about new product. On the other hand, using brainstorming allow to get various ideas, but to get a lot of unavailable ideas together. In this study, to support generating various and effective ideas in conceptual design, we propose two conceptual design support methods based on Data Envelopment Analysis and Analytic Hierarchy Process. The former is the method using several evaluation values to fill the gap of palate frontier and creating hierarchy graphs. The latter is method establishing a prioritized list of all ideas by paired comparison. Various information is given to the designer from these graphs when they conceive new ideas. We verified which technique is effective to obtain new ideas with high evaluation by comparing these two methods. The result shows that the proposed method using hierarchy graphs is more efficient than the other way using the prioritization graph.

  • 406 Structural analysis of elastic body using Cellular Automaton and GPGPU

    SHIRAI Tomohiko, MIYASHITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2010

  • 2417 Structural optimization for energy absorption in a train collision

    KOMATSUZAKI Makoto, MIYASHITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2009

     View Summary

    As compared with automobile, few train design methods for crashworthiness have been proposed. To establish it, we paid attention to double structure composed of train exterior and cabin, and designed train finite element model. We changed the position and thickness of steel plates joining these two constituents, and simulated train collision to a rigid body wall at the speed of 60 kilometer per hour. As a result of the optimization, it was shown that distortional energy in the cabin and maximum deceleration were reduced. We discussed relation of between absorbed energy and maximum deceleration, and introduced new train structure.

  • 2206 A study on optimization of nano-satellite structure

    SAITO Keisuke, MIYASHITA Tomoyuki, TSUNODA Hiroaki, WATANABE Kazuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2009

     View Summary

    Recently the development of the small satellite becomes active. In general, small satellites are expected to be developed faster and cheaper than the large satellites. A cost of a piggyback satellite is often decided by weight. Therefore it is important to reduce the weight of satellite for cost. Considering the severe mechanical environment of launching, we have to design satellite structure. The natural frequency of the satellite should be higher than the value decided by the launching and the satellite should bear the loads during launch. And the satellite should be considered with the value of the moment of inertia and a center of gravity because of stability of position. In this paper, we will propose the design of the satellite whose dimension is 20 centimeters cube. We focused on the trade-off design between minimization of stress condition and the appropriate center of gravity and the moment of inertia under the minimum natural frequency and the maximum mass for optimizing the satellite structures.

  • 1907 The real time needle inset simulation considering inside deformation

    YOSHITAKE Yusuke, MIYASHITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2009

  • G1201-1-1 A Study of an evaluation of a safety behavior of the passengers in the railroad impact

    SHIMADA Masayuki, MIYASHITA Tomoyuki

    The Proceedings of Mechanical Engineering Congress, Japan 

    Presentation date: 2009

     View Summary

    This study treats human body model and cellular automata for analysis of the passenger behavior for the deceleration at the time of the railway accident. At this case, the deceleration obtained from simulation of the railroad carriage model is used for simulation suppose to collision to the rigid body wall. Consequently, it was shown that injury to the passenger was able to be reduced by the parameter of the partition and the floor when accident was occured.

  • A Study on Idea Generation Method for Concept Design Using Data Envelopment Analysis(Machine Elements, Design and Manufacturing)

    SATOH Daisuke, KOBAYASHI Masakazu, MIYASHITA Tomoyuki

    TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C 

    Presentation date: 2009

     View Summary

    At an early stage of design process, it is required to discuss many ideas derived from design requirements using designer's knowledge and experiences. Especially, at conceptual design stage, many designers often discuss together about new product and discuss design ideas considering its effectiveness. However, according to increasing the complexity of the functions of products and variety of consumer's needs in recent years, it becomes difficult for designers to discuss about ideas by only conversations and figures. Then, in the conceptual design process, it is required to derive many ideas that meet the design requirement considering the complicated requirements. The derivation process of ideas often wastes the time because of the inertia of designer's thinking process. In this study, we will propose the method to support derivation process from the visualized relation using Data Envelopment Analysis. Through the experiment, we will confirm the effectiveness of our study.

  • 3・4 CAE・最適化等についての研究動向(3.計算力学,<特集>機械工学年鑑)

    宮下 朋之

    日本機械学会誌 

    Presentation date: 2009

  • 1111 A Fundamental Examination on a Concept Design Support using Neural Network

    SATOH Daisuke, MIYASHITA Tomoyuki

    Presentation date: 2008.09

     View Summary

    In conceptual design phase, if designers are much more conscious of design objectives, they won't come up with various ideas about new product. On the other hand, using brainstorming allow to get various ideas, but to get a lot of unavailable ideas together. In this study, we propose the method that supports generating various and effective ideas in conceptual design. In the last our study, we have proposed conceptual design support method using Data Envelopment Analysis. The last method's approach is using several evaluation values to fill the gap of palate frontier. But it was too difficult for subjects to use this approach in the experiment. Proposed method in this paper supplies key words. These key words are made of calculated component values using made nonlinear mathematical model of relation between component and evaluation of idea with Neural Network. We confirm that the method is useful in terms of simplicity of generating various and effective ideas.

  • 3116 A study on optimization of nano-satellite structure

    SAITO Keisuke, MIYASHITA Tomoyuki, TSUNODA Hiroaki, WATANABE Kazuki

    Presentation date: 2008.09

     View Summary

    Recently the development of the small satellite becomes active. In general, small satellites are expected to be developed faster and cheaper than the large satellites. The launching cost of the piggyback satellite is low, and then a cost of a piggyback satellite is often decided by weight. Therefore it is important to reduce the weight of satellite for cost. Considering the severe mechanical environment of launching, we have to design of satellite structure. The natural frequency of the satellite should be higher than the value decided by the rocket and the satellite should withstand the loads during launch. In this paper, we will propose the design of the satellite whose dimension is 20 centimeters cube. The satellite supposed to be launched by H-2A rocked and we focused on the trade-off design between minimization of mass and maximization of natural frequency under the maximum stress condition for optimizing the satellite structures.

  • Collaboration Support System Based on Assessment of Created Ideas Using Data Envelopment Analysis

    KOBAYASHI Masakazu, MIYASHITA Tomoyuki, YAMAKAWA Hiroshi, YOSHIMURA Masataka

    Transactions of the Japan Society of Mechanical Engineers C 

    Presentation date: 2008.02

     View Summary

    This paper focuses on the creative aspects of collaboration and proposes a method for analyzing created ideas to help designers to enhance designers' creativity during collaborative design projects. The proposed method is based on DEA (Data Envelopment Analysis), analyses ideas created by designers to reveal characteristics and overall effectiveness of each idea, interrelationship between ideas and potentially fruitful directions for improvement of created ideas and exploration of new ideas and aims to help designers explore more sophisticated ideas. To enable smooth collaboration when using the proposed analysis method, this paper also proposes a computerized support system. This system is based on a combination of the analysis method proposed here, and the method for visualizing interactive communication processes proposed in our previous work. Analyzing system analyzes created ideas and visualizes the results from the multiple viewpoints, whereas visualizing system records interactive communication processes among designers and visualizes them in an easyto-understand way.

  • 835 An Evaluation of The Real-time Needle Insertion Simulation System

    YAMANAKA Masaki, MIYSITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2008

     View Summary

    The simulation system that calculates the behavior of the liver by needle insertion in real time, displays the results, and outputs the reaction force to the kinesthetic sense device was developed. The finite element method was used for the calculation of the behavior of the liver. Considering the calculation load, the algorithm to achieve the real-time processing was developed. The simulation system was evaluated from calculating load by using the liver models with different number of elements. It was the model with 905 elements and 209 nods that met the requirement for the real-time processing (calculation speed is 30Hz or more).

  • 908 A Study of an evaluation of a safety between human and car equipment in the railroad impact

    KATAOKA Kosuke, MIYSITA Tomoyuki

    The Proceedings of The Computational Mechanics Conference 

    Presentation date: 2008

     View Summary

    This study treats the reduction of the degree of the passenger injury by analyzing the behavior of 133 passengers being in a commuter vehicle at the time of the impact of the railroad accident outbreak with a computer. Judgment the degree of the injury of the passengers and inspection of the global safety was enabled by developing the behavior analysis program of the passengers with cellular automata with C language and analyzing with a large number of people. In addition, the safety improvement effect of the straps was confirmed by comparing the injury judgment value of the model increased the number of the straps to the normal model.

  • 1P1-C10 Robotic heart-beat simulator to evaluate a surgical robot system with heart-beat canceller

    OKADA Kaoru, KATO Atsuhi, NOGUCHI Toyohiro, TOYODA Kazutaka, KAWAMURA Kazuya, KOBAYASHI You, OKAMOTO Jun, MIYASHITA Tomoyuki, FUJIE Masakatsu G

    Robomech 

    Presentation date: 2008

     View Summary

    This paper presents the development of robot capable to simulate heartbeat. It is difficult to operate off-pump coronary-artery bypass surgery. Consequently, we develop the surgical robot system with heart-beat compensation. In the process of developing the robot system above, it is necessary to evaluate the tracking capability of the robot system quantitatively. Therefore, we developed the Robotic heart-beat simulator which evaluates the robot system. First of all, required specification of the robot was found by the heartbeat data in vivo experiment. Second, the link parameters of the robot that satisfy the specification were optimized. At the end, the robot was evaluated for accuracy of position and posture. As a result, the robot moved with maximum error of 0.28 [mm] and 0.54 [deg]. In addition, the robot was evaluated in the experiment of movement based on the heartbeat data, it showed a little error and time-lag, but utility of the robotic heartbeat simulator.

  • 3305 A Study on Derivation of Design index using Vehicle Structure and Performance Data By Data Envelopment Analysis

    FUKUNISHI Hirotomo, MIYSITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2008

     View Summary

    In this research, we analyzed the automotive data that contain bringing the automotive performance from about 300000 models from which they were open to the public from 1982 to 2006 years about 20000 models by Data Envelopment Analysis. DEA is the method that can make clear superiority or inferiority of business unit with multi-dimensional index and showing improvement direction of business unit. As a result, we can show trends from graph where horizontal axis was assigned as each performance index and vertical axis was assigned as each efficiency value obtained by DEA. We showed design index of automotive in the future by sensitivity analysis. From the above-mentioned method, we can confirm DEA is the effective method as method of evaluating products with multi-dimensional index.

  • 周期的熱荷重による試験環境変動にロバストな熱変形試験法の成立性評価

    宮﨑哲大, 石村康生, 佐藤泰貴, 宮下朋之

    第33回宇宙構造・材料シンポジウム 

    Presentation date: 2007.12

  • Development and evaluation of the Needle Insertion Surgery Simulation System

    Nakamura Takuma, Miyashita Tomoyuki, Yamakawa Hiroshi

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2007

     View Summary

    The surgery simulation system for training purpose is useful for training and planning. The system displays the deformation of the human organs calculated using Finite Element Method (FEM) and output the reaction forces with force feedback devices. However, FEM prevents a real time simulation because of high computational cost. In this study, we have developed a Needle Insertion Surgery Simulation System, which has the ability to compute reaction forces and simulates dynamical behaviors in real time using a simple calculation method. Here, we have proposed and discussed a simple method to compute reaction forces from internal stress distribution, which is calculated using FEM. Considering the DOF of the model and computational cost; we have discussed the effectiveness of the proposed method, and the possibility to develop the system.

  • Designing the Path and Retainer Tools for Needle Insertion Surgery

    Md.Kzamani, T.Miyashita, Y.Kobayashi, H.Yamakawa, J.Okamoto, Masakatsu.G.Fujie

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2007

     View Summary

    The minimal invasive surgical technique used for treatments on cancer infected liver is comparatively to be effective due to fast recovery of the wound and the rehabilitation period. Needle insertion planning shows its difficulties when needle contact the tissue structures and become complicated with existence of gravity, cancer size and position, needle properties and surrounding organs. In this study, a constitutive equation of viscoelastic material properties of liver is formulated using measured experimental results on pig&prime;s liver. 3-D Finite Element Model is created using sliced MRI images. Approximations were made on friction between needle and soft tissue, and the condition of tear-off elements integrated with quasi-static analysis. In simulation, we proposed a retainer tool to minimize the displacement of the cancer infected part as a new boundary condition. Numerical results by proposed boundary condition technique show the possibility to design a new device in order to navigate needle to hit the cancer precisely.

  • A Fundamental Examination on a Conceptual Design Support using Data Envelopment Analysis

    Satoh Daisuke, Miyasita Tomoyuki

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2007

     View Summary

    概念設計段階における分野の異なる設計者集団の合意形成支援,及び目的に沿う多様なアイデアの発想支援を目的とする.複数のアイデアをアンケートで点数評価し,データ包絡分析法を用いて階層関係を提示することで,アイデアの上位関係の空間的な把握を支援する手法を提案した.CDプレーヤーを対象に被験者に概念設計を試行的に行い,提案手法の有用性の検討を行い,多様なアイデアを探索できる点で有用であることが認められた。

  • 2106 Fundamental Study using Vehicle Structure and Performance Data By Data Envelopment Analysis

    FUKUNISHI Hirotomo, MIYSITA Tomoyuki

    The Proceedings of Design & Systems Conference 

    Presentation date: 2007

     View Summary

    In this research, we analyzed the automotive market bringing the automotive performance from about 300000 models from which they were open to the public from 1982 to 2006 years about 20000 models by Data Envelopment Analysis. DEA is the method that can make clear about superiority or inferiority of business unit with multi-dimensional index and showing improvement of business unit. As a result, we can show trends from graph where horizontal axis was assigned as each performance index and vertical axis was assigned as each efficiency value obtained by DEA. We showed design index of automotive in the future by sensitivity analysis. From the above-mentioned method, we can confirm DEA is the effective method as method of evaluating products with multidimensional index.

  • 2306 The safety of the passenger in the railroad collision

    KATAOKA Kosuke, MIYSITA Tomoyuki, YAMAKAWA Hirosi

    The Proceedings of Design & Systems Conference 

    Presentation date: 2007

     View Summary

    This study treats the reduction of the degree of the passenger injury by analyzing the behavior of the passenger sitting on a box seat at the time of the collision outbreak of the railroad carriage by simulation. Judgment the degree of the passenger injury was enabled by development the behavior analysis program of the passenger with C language and inputting a decelerating acceleration wave pattern at the time of the vehicle collision obtained by the finite element analysis. Injury judgment values decreased by more than 30% by optimizing to assume the spring constant of the seat as a design variable to reduce an injury judgment value.

  • 2P1-C03 A Real Time Simulation using Finite Element Method : Confirmation using Haptic Device

    YAMAUCHI Hiroshi, MIYASHITA Tomoyuki, INUI Masatomo, YAMAKAWA Hiroshi

    Robomech 

    Presentation date: 2006

     View Summary

    In this study, we will review the previous studies treating same problem using FEM analysis and propose the method to treat the cutting simulation considering real time computation and simulation results are directly transferred to the user through the haptic device. The hex and tetra elements were used to model the structure using FEM analysis and dynamical response was calculated using wilson θ method. Here, the elements matrix was normalized according to the distance between a cutting device and nodes to omit the re-mesh procedures. The proposed method was implemented using three threads that handle graphics for display, dynamical calculation and model construction to improve the response for user operation. Then, we have developed the simulation system composed of the haptic device (PHANToM force feedback device) using ToolKit and the proposed method including graphics animation.

  • 2A1-A03 Development of a Respiratory Surgical Navigation System for Identifying a Position of a Metastasis Cancer in a Collapsed Lung

    YOSHIZAWA Aiko, KOBAYASHI Yo, OKAMOTO Jun, MIYASHITA Tomoyuki, YAMAKAWA Horoshi, FUJIE Masakatsu G

    Robomech 

    Presentation date: 2006

     View Summary

    This paper shows the development of a respiratory surgical navigation system for the metastasis cancer in a collapsed lung. This system has two navigation methods, (a) Collapsed simulation,(b) Palpation using manipulator. Collapsed simulation provides the position of the cancer in a collapsed lung using the preoperative CT Data. Palpation using manipulator after collapsed simulation provide more precise position of collapsed lung.

  • 117 A collaborative support method based on analysis of created ideas

    KOBAYASHI Masakazu, MIYASHITA Tomoyuki, YAMAKAWA Hiroshi, YOSHIMURA Masataka

    Designシンポジウム講演論文集 

    Presentation date: 2006

     View Summary

    This paper focuses on the creative aspects of collaboration and proposes a method for analyzing created ideas to support collaborative design processes. The proposed method, based on DEA (Data Envelopment Analysis), analyses created ideas, reveals their characteristics and interrelationships, clarifies potential directions for improvement of created ideas as well as potentially fruitful directions for exploration of new ideas, and aims to help designers explore more sophisticated products. To enable smooth collaboration when using the proposed method, a computerized support system is constructed. This system is based on a combination of the analysis method proposed here, and the method for visualizing interactive communication processes proposed in our previous work.

  • 3201 An Optimal Design of Partially Rigidizable Inflatable Structures

    Sato Nobuaki, IWAKOSHI Tomoyuki, TSUNODA Hiroaki, YAMAKAWA Hiroshi, MIYASHITA Tomoyuki

    The Proceedings of Mechanical Engineering Congress, Japan 

    Presentation date: 2006

     View Summary

    In this study, we proposed partially rigidizable inflatable structures consist of rigidizable layers on the part where to be stiffened. As a result of tension test of the test specimen, we could make the property of the material clear. Furthermore, we made a initial model that wholly covered hemisphere structural model and the topology optimization was applied to find the optimum arrangement of regidizable layers. As a result, the number of edge reduced to 35 lines, and considering the volume to 11% lower than that of the basic model. From the point of view of manufacturing, stiffness and stress concentration, we could suppose that the basic model is suitable for our required.

  • 力覚デバイスによる物体切断シミュレーション

    日本精密工学会 

    Presentation date: 2005.03

  • GPUを利用した二次元応力場における簡易計算と最適化の検討

    日本精密工学会 

    Presentation date: 2005.03

  • 探索方向の傾斜によるPSO法の改良に関する検討

    日本精密工学会 

    Presentation date: 2005.03

  • Improvement of Parameter Study tools with Contribution to percent change

    Saito Tomoyuki, Miyashita Tomoyuki, Inui Masatomo

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2005

     View Summary

    In a design, when defining parameters, generally the value that a designer can satisfy is found out using the calculating methods, such as the optimum designing method and the satisfactory designing method. However, since the influence to the performance and conditions which each parameter does etc. is grasped, the value of a variable is changed and work of repeating inquiring and performing it may be performed. This is called &ldquo;Parameter Study&rdquo;. In this paper, in order to enable it to perform a Parameter Study Tool visually, I made the parameter study tool using 3D-Graphics build, and decided that it applies to some exercises and inquires.

  • Analysis of a product data by Data Envelopment Analysis

    Morooka Hiroaki, Inui Masatomo, Miyasita Tomoyuki

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2005

     View Summary

    To pursue the profit of the business, the maximization of the profit to the development cost is demanded. The designer must be demanded an improvement of the function and performance which are superior to ones of other companies. This research, a certain product is compared with the other product in the various points of view. And the efficiency value of the product is calculated by using Data Envelopment Analysis. The purpose is to support deriving the target of the product development with good performance. In conclusion, this research succeeded in deriving the target of the product development with good efficiency value. The designer can understand a part of policy of a new product development from efficient product data.

  • Development and Basic Study of Parameter Study tools

    JSME Mechanical Engineering Congress /JSME 

    Presentation date: 2004.09

  • パラメータスタディツールの開発と基礎的検討

    日本機械学会 

    Presentation date: 2004.09

  • 面法線情報を伴うZ-マップ表現を利用した加工シミュレーションの高精度化

    日本精密工学会 

    Presentation date: 2004.09

  • Development of Genetic Range Genetic Algorithms : 3rd Report, Proposal of Fitness Function to Search Multiple Local Optima

    ARAKAWA Masao, MIYASHITA Tomoyuki, ISHIKAWA Hiroshi

    Transactions of the Japan Society of Mechanical Engineers. Series C. 

    Presentation date: 2004.07

     View Summary

    In some cases of developing a new product, response surface of an objective function is not always single peaked function, and it is often multi-peaked function. In that case, designers would like to have not only global optimum solution but also as many local optimum solutions as possible, so that he or she can select one out of them considering the other conditions that are not taken into account priori to optimization. Although this information is quite useful, it is not that easy to obtain with single trial of optimization. In this study, we will propose a screening of fitness function in genetic algorithms, and give rough search for local optima. Once after they are obtained we will carry out local search to obtain multiple quasi-optimum solutions. In this paper, we demonstrate the effectiveness of the proposed method through a simple benchmark test problem.

  • An application of Discrete shape expression considering normal line information]

    JSPE Precision Engineering Conference (Spring) / JSPE 

    Presentation date: 2004.03

  • 法線情報を伴う離散的形状表現のCAMでの利用

    日本精密工学会 

    Presentation date: 2004.03

  • 最適設計におけるパラメータスタディツールの開発

    日本機械学会 

    Presentation date: 2004.03

  • データ包絡分析法による協調設計に関する研究

    日本機械学会 

    Presentation date: 2004.03

  • A Study on Quasi-Optimum Solutions of Job Shop Scheduling Problems

    長谷川 聡, 宮下 朋之, 乾 正知

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2004

     View Summary

    最適化手法の多くは解が1つしか求まらないため,複数の解を求めるには初期点などのパラメータを変えてやり直さなければならないといったような工夫がなされている.1度の計算で複数の異なる解を提示する方法があれば,目的関数や制約条件を変更しても再計算しなくて良い可能性がある.本研究では,免疫アルゴリズムを改善し,ジョブショップスケジューリング問題を含むいくつかの問題に適用し,研究手法の有効性を検討する.

  • Development of Genetic Range Genetic Algorithms (3rd Report, Proposal of Fitness Function to Search Multiple Local Optima):3rd Report, Proposal of Fitness Function to Search Multiple Local Optima

    ARAKAWA Masao, MIYASHITA Tomoyuki, ISHIKAWA Hiroshi

    TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C 

    Presentation date: 2004

     View Summary

    In some cases of developing a new product, response surface of an objective function is not always single peaked function, and it is often multi-peaked function. In that case, designers would like to have not only global optimum solution but also as many local optimum solutions as possible, so that he or she can select one out of them considering the other conditions that are not taken into account priori to optimization. Although this information is quite useful, it is not that easy to obtain with single trial of optimization. In this study, we will propose a screening of fitness function in genetic algorithms, and give rough search for local optima. Once after they are obtained we will carry out local search to obtain multiple quasi-optimum solutions. In this paper, we demonstrate the effectiveness of the proposed method through a simple benchmark test problem.

  • A Development of Parameter Study Tools for Design Optimization

    MIYASHITA Tomoyuki, Saitoh Tomoyuki

    The Proceedings of Conference of Kanto Branch 

    Presentation date: 2004

  • An Examination on Collaborative Optimization Method considering Cutting Plane

    MIYASHITA Tomoyuki, INUI Masatomo

    The Proceedings of Design & Systems Conference 

    Presentation date: 2004

     View Summary

    In design processes, designers have to propose many design alternatives to satisfy requirements for products and evaluate considering many features or properties of design. Then a final design should be decided from many discussion and evaluation. In these processes, conflicts among designs can be often seen and sometimes designes take time to solve conflicts through discussion and so on. The Multi-objective optimization techniques are useful to consider trade-off between conflict properties. However, in these techniques, unification of objective functions is necessary and in almose case, unification function with weights that should be decided before optimization is used. In this study, we have extend previous proposed evaluation method of designs using cutting plane for weights in Data Envelopment Analysis and evaluated its effectiveness through some numerical examples.

  • 多様性を考慮したジョブショップスケジューリング問題の検討

    日本機械学会 

    Presentation date: 2003.10

  • 離散的な形状表現に基づく幾何学的に滑らかな工具経路の生成

    日本精密工学会 

    Presentation date: 2003.10

  • A Development of Collaborative Design System using Data Envelopment Analysis

    JSPE Precision Engineering Conference (Spring) / JSPE 

    Presentation date: 2003.03

  • データ包絡法を用いた協調設計システムの構築

    日本精密工学会 

    Presentation date: 2003.03

  • Smooth Tool Path Generation Based on a Discrete Shape Representation

    Tsukada Yosuke, Miyasita Tomoyuki, Inui Masatomo

    Proceedings of JSPE Semestrial Meeting 

    Presentation date: 2003

     View Summary

    金型の粗加工用の工具経路は多くが逆オフセット法を用いて計算され、逆オフセット面は離散的な情報に基づく微小な点の集合を元にした膨大な数の多角形の集合として得られる。本研究では、製品形状を構成する面、辺、頂点の情報に基づいて逆オフセット面を構成する点を分類し、より滑らかな工具経路を計算し表示することを目的とする。

  • An Examination on Jobshop Scheduling Problem in consideration of diversity

    HASEGAWA Satoshi, MIYASITA Tomoyuki, INUI Masatomo

    The Proceedings of Design & Systems Conference 

    Presentation date: 2003

     View Summary

    In a production process design, it is required to define working time and scheduling by the number of a machine and performance but single solution is calculated when existing method is applied. It is necessary to propose some schedules and to assist a designer. In this study, immune algorithm is used and improved to solve jobshop scheduling problem known as a difficult problem in combination optimization problems and genetic algorithm is compared with immune algorithm for this problem. Through some examples, we showed that some optimal solutions and quasi-optimal solution could be found

  • 多様性を考慮したジョブショップスケジューリングの決定

    宮下 朋之, 乾 正知

    精密工学会大会学術講演会講演論文集 

    Presentation date: 2002.10

  • 金型粗加工のための逆オフセット面に基づく工具経路の生成手法

    崔 原己, 宮下 朋之, 乾 正知

    精密工学会大会学術講演会講演論文集 

    Presentation date: 2002.10

  • A Generation method for tool path using Inverse Offset Plane

    JSPE Precision Engineering Conference (Autumn) / JSPE 

    Presentation date: 2002.09

  • A Discussion on Job-shop Scheduling Problem considering Environment Properties

    JSPE Precision Engineering Conference (Autumn) / JSPE 

    Presentation date: 2002.09

  • A Study on Structural Optimization using Immune System

    JSME Mechanical Engineering Congress /JSME 

    Presentation date: 2002.09

  • 金型粗加工のための逆オフセット面に基づく工具経路の生成手法

    日本精密工学会 

    Presentation date: 2002.09

  • 多様性を考慮したジョブショップスケジューリングの決定

    日本精密工学会 

    Presentation date: 2002.09

  • 免疫システムによる設計最適化に関する研究

    日本機械学会 

    Presentation date: 2002.09

  • Multi-Criteria Decision Making Environment with Optimization Software iSIGHT

    宮田 悟志, 米澤 智志, 工藤 啓治, 廣安 知之, 三木 光範, 宮下 朋之

    The Proceedings of Mechanical Engineering Congress, Japan 

    Presentation date: 2002

     View Summary

    In design process, not one characteristic but are multiple characteristics should be offten considered. If all of the characteristics have no correlation each other, design problem would be very easily solved, however, in most of actual cases, there are significant correlations between those design characteristics and it makes design review difficult. Such kind of problem has been studied as Multi-Criteria Decision Making (MCDM) or Multi-Objective Programing (MOP) by researchers and have not been perceived as general tools for designers. Nowadays, however, such kind of tasks to meet several conflicting design/production requirements became common due to heigh product requirements. And design tools, which enable designer to perform MCDM or MOP in their usual design tasks, are desired. iSIGHT is a MDO (Multi-Disciplinary Optimization) software system developed by Engineous Software Inc. and has numbers of practical applications in design optimization problems. This paper introduces current functions and recent development efforts on MCDM and MOP in iSIGHT.

  • A Fundamental Examination and Development of the Distributed Design Environment using Computer Networks

    MIYASHITA Tomoyuki, INUI Masatomo

    The Proceedings of Design & Systems Conference 

    Presentation date: 2002

     View Summary

    In design of machinary, computers are very useful and many jobs are aided by computer system and treated more efficient than before. Under recent sever economical environment, cost-benefit becomes important and many computer systems are developed for the sake to do jobs efficiently. Computer networks is the result of the ARPA project and now, this becomes important infrastructure. The success of the design system using computer networks becomes the key-point of the success of the bussiness and design of the product. In this fundamental examination, the authors have developed the design system for the design optimization under computer networks and tried to apply for the simple numerical examples.

  • A Study on Integration of Distributed Models and Collaborative Design

    MIYASHITA Tomoyuki, INUI Masatomo

    The Proceedings of Design & Systems Conference 

    Presentation date: 2002

     View Summary

    The various information is treated in design processes by many designers. In the design of complicated machinary, designers often treat information and make various decision for the design. Recent years, computational power has been increasing and designers could discuss design problems from several points of view. Optimization methods offer reasonable design canditates from the early stage of design. However, in the discussion from several points of view, the unification of the distributed models is useful and it is difficult to make decision to settle design canditates. In the unification of the models, the overlap of the information often occures. In this study, we will develop the database that treats the overlap of the information and apply the developed system for the collaborative design. Through simple numerical examination, we will confirm the effectiveness of the developed system.

  • A Study on Structural Optimization using Immune System

    JSME Engineering Congress/JSME 

    Presentation date: 2001.08

  • 免疫エージェントによる最適設計に関する研究

    日本機械学会 

    Presentation date: 2001.08

  • A Study on Optimum Design using Search Agents

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    Proc. of JSCES Conf./JSCES 

    Presentation date: 2001.05

  • Report of Design Optimization and Satisfaction Research Commitee

    Report of JSCES/JSCES 

    Presentation date: 2001.05

  • 「多目的最適化設計・満足化設計」

    日本計算工学会 

    Presentation date: 2001.05

  • 探索エージェントによる多点同時探索戦略による最適設計に関する研究

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    日本計算工学会 

    Presentation date: 2001.05

     View Summary

    Many optimization methods and practical softwares have been developing for many years and most of them are very effective, especially to solve practical problems. But, non linearity of objective functions and constraint functions, which have frequently seen in practical problems, has caused a difficult situation for optimization. This difficulty mainly lies in the existence of several local optimum solutions. In this study, we have proposed a new global optimization methodology that provides an information exchange mechanism in the nearest neighbour method. We have developed a simple software system, which treated each design point in optimization as an agent. Many agents can search the optima simultaneously exchanging the their information. We have defined two roles of the agents. Local search agents have roles on searching local optima by an existing method like the steepest decent method and so on. Stochastic search agents investigate the design space by making use of the information from other agents. Through simple and several structural optimization problems, we have confirmed the advantages of this method.

  • 協調設計システムの検討-複合領域問題の検討-

    日本機械工学会 

    Presentation date: 2001.03

  • An Examination on Collaborative Design System

    Proc. of Design Eng. and System Conf./JSME 

    Presentation date: 2001.01

  • K-0215 A Study on Structural Optimization using Immune System

    宮下 朋之, 坪田 有玄, 山川 宏

    The Proceedings of Mechanical Engineering Congress, Japan 

    Presentation date: 2001

     View Summary

    Immune system in mammals plays a significant role on the survival in the case with attacking of various bacteria. This system seems to equip the mechanism eliminate the various vacteria. From the view point of information mechanism, this system could offer the designs that are considered with the environmental situation, for example, wind loads, deterioration and so on. Especially, immune algorithms are considered as the optimization algorithms. However, the immune algorithms are not fully established becase various algorithms are considered and fully investigated. In this study, from above point of view, we will propose the immune algorithm that treates the "antibody-antigen reaction". Through some numerical examples, we will show the effectivenews of th proposed algorithm.

  • An Examination on Collaborative Design System : Treatement of Multidisciplinary Design Problem

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    The Proceedings of Design & Systems Conference 

    Presentation date: 2001

     View Summary

    Recent years, computational power has been incresing and designers could discuss design problems from several points of view. In these discussions, simulations using computers could offer useful information to evaluate their designs to develop profitable products exceeding the competitor's product. Optimization methods offer reasonable design canditates. However, in the design in which some technical fields are included, it is difficult to make decision to settle design canditates. In our previous study, we have proposed the method that led designers to collaboration and developed the software system. In this paper, we have examined the developed system through the some design problems.

  • 3402 A Study on Approximate Multi-Objective Optimization in Multi-Objective Design Considering Accuracy

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    The Proceedings of Design & Systems Conference 

    Presentation date: 2001

     View Summary

    In optimization algorithms, the value of design variables are updated according to some criterion and it is nesessary to evaluate objective functions and constraints repeatedly if design variables are updated. In design problems, performances are often taken as the objective functions or constraints and it needs a time to evaluate the performances. A same situation is observed in the multi-objective optimization problems that can handle several objective function simultaneously and is suitable for the real design. Therefore it is desiable to decrease the number of evaluation count of the objective function and constrains. The response surface methodology is helpful for such a situation and many studies have been done. In real design problems, nonlineality of the objective function and constraints can been seen and this make the objective function or constraints the complex form about the design variables. On the other hand, in the mult-objective optimization problems, we have to calculate the pareto optimal set that could not be defined the inferiority or supriority among the solutions. The pareto optimal set forms the hyper plane in objective function space and the sensitivity of this plane make us to be able to do the trade-off analysis among the objective functions. The difficulty to obtain pareto optimal set could be seen in calculation because of the nonlinearity of the objective function and constraints. That is, it seems to be difficult to fund some part of pareto optimal set in probablistic method. In this study, we will approximate the pareto optimal set using response surface methodology and identify the region that needs evaluation. Through numerical example, we will discuss the fundamental charastaristics of the proposed method

  • 1104 A Study on Collaborative Design using Supervise Agents

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    The Proceedings of Design & Systems Conference 

    Presentation date: 2001

     View Summary

    In the case that mechanical system is large or complicated, design of the system is often divided into design of its components and integrated from design resulted from the devided design level. Therefore designers have to integrate their components design into final design. However, in this stage, it can be seen some conflicts and it is important to resolve these conflict to make shorten the leadtime of design process and make profit. Recently, we can widly use computers in various design stages and we can decrease the number of times of time-consuming real experiments using analytical software. It can be seen the situation that offices of designers are apart from each other and the same situation for computers and analytical software in the offices. In this research, we proposed the collaboration design method that resolve the conflict among designs connecting the computers using networks. In our previous paper, we have proposed the design evaluation method using Data Envelopment Analysis and calculation method of compromise design. We have confirmed that it is effective to offer compromise information in the stage of components design. In this paper, we have improved our proposed that can offer the direction for compromise design and confirmed the effectiveness of the proposed method through some numerical examples.

  • ネットワークを利用した協調的最適設計システムの構築及び検討

    日本機械学会 

    Presentation date: 2000.10

  • An Examination and A Development of the Collaborative Optimization System on Computer Network

    Proc. of System Optimization Symposium 

    Presentation date: 2000.10

  • An Examination on Structural Optimization using Immute Agents

    JSME Mechanical Engineering Congress/JSME 

    Presentation date: 2000.08

  • 免疫エージェントによる最適設計に関する研究

    日本機械学会 

    Presentation date: 2000.08

  • スーパバイズシステムによる多目的最適化に関する研究

    情報処理学会 MPSシンポジウム 講演論文集/情報処理学会 

    Presentation date: 2000.03

  • A Study on Multi-Objective Optimization using Supervise System

    MPS Symposium/IPSJ 

    Presentation date: 2000.03

  • An Examination on Structural Optimization using Immute Agents : An Examination on An Antigen-Antibody Reaction

    宮下 朋之, 坪田 有玄, 山川 宏

    The Proceedings of Mechanical Engineering Congress, Japan 

    Presentation date: 2000

     View Summary

    We, human being, have survived and prosperd in a biological systems and an immute system plays a significant roll in protecting us against foregin bacillus. From the results of the study field in information processing, it is pointed out that the immute system is capable of learning, memory, pattern recognition and optimization using genetic operators. In the optimization of mechanical and structural designs, an environment of products is significant factor to decide the design. In this study, we will treate the design variables in the optimization problem as antibody and the environment as the antigen. We treated simple numerical examples and they resulted the design stored in memory-cell with best evaluation and worst evaluation considering environment. We have confirmed that the design canditates including the design obtained by mathematical programming are found among the results.

  • An Examination and A Development of the Collaborative Optimization System on Computer Network : Applying the Trade-off Satisficing Method

    MIYASHITA Tomoyuki, YAMAKAWA Hiroshi

    The Proceedings of OPTIS 

    Presentation date: 2000

     View Summary

    Recent years, financial difficulties led engineers to look for not only the efficiency of the function of a product but also the cost of its development. In order to reduce the time for the development, engineers in each discipline have to develop and improve their objectives collaboratively. Sometimes, they have to cooperate with those who have no knowledge at all for their own disciplines. Collaborative designs have been studied to solve these negotiations will be done successfully. However, in the most cases of real designs, manager of each discipline does not want to give up his or her own objectives to stress on the other objectives. In order to carry out these negotiations smoothly, we need some sort of evaluation criteria which will show efficiency of the product considering the designs by each division and if possible, considering the products of the competitive company, too. In this study, we use data Envelopment Analysis (DEA) to calculate the efficiency of the design and showed every decision maker the directions of the development of the design. We will call here these kinds of systems as supervisor systems and implemented these systems in computer networks that every decision maker can use conveniently. Through simple numerical examples, we showed the effectiveness of the proposed method.

  • A Study on the Collaborative Design using Supervise Agents

    Proc. of Design Eng. and System Conf./JSME 

    Presentation date: 1999.11

  • 複合領域設計システムの構築と検討

    日本機械学会 講演論文集/日本機械学会 

    Presentation date: 1999.11

  • An Examination and Development of Multidisciplinary Design System

    Proc. of Design Eng. and System Conf./JSME 

    Presentation date: 1999.11

  • スーパバイズエージェントによる協調設計に関する研究

    日本機械学会 講演論文集/日本機械学会 

    Presentation date: 1999.11

  • A Study on the Collaborative Optimization Using a Supervisor System

    Proc. of CJK-OSM1/JSME,KSME 

    Presentation date: 1999.11

  • Function of Gene in Adaptive Range Genetic Algorithms

    Proc. of CJK-OSM1/JSME,KSME 

    Presentation date: 1999.11

  • 多点同時探索戦略を用いた検索エージェントによる最適設計に関する研究

    日本機械学会 講演論文集/日本機械学会 

    Presentation date: 1999.07

  • 複合領域最適化における設計支援システムに関する検討

    設計シンポジウム99講演論文集/設計工学会他 

    Presentation date: 1999.07

  • An Examination on the Multidisciplinary Design Optimization System

    Proc. of Design Symp./JSME 

    Presentation date: 1999.07

  • An Examination on the Optimum Design by Search Agents With Multi-Start Search Strategy

    JSME Mechanical Engineering Congress /JSME 

    Presentation date: 1999.07

▼display all

Specific Research

  • 多重らせん折収納膜面の展開機構の考案と宇宙実証

    2020   Parque VICTOR, 三浦 智

     View Summary

    平面の膜面を収納するために、従来の円筒形状を変更し、角柱形状に収納する方法を考案した。さらに、角柱に巻き付く方向を逆転する方法を考案し、展開を容易に角柱形状へ収納する方法を考案した。展開においてはコンベックスrテープを使用して、展開する方法を検討し実証した。また、複数のらせん折形状の膜面を接続し、より大きな平面を複数の角柱形状に収納して展開する方法を提案し実証した。宇宙における実証については、革新3号機への実施プロジェクトへ応募し採択され、考案した膜面を搭載した人工衛星をイプシロンロケットによる打上げる契約を締結し、人工衛星を製作中である。

  • 触診術の定量的評価及び機械システムによる支援方式に関する研究

    2019  

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    本研究では, 臓器の機械的特性をオンライン 同定するシステムを構築することを目的と する.ここで,以下二つの点に着目する.一点目は, 実臓器の形状から実環境に適した有限要素臓器モデルの構築である. 多くの従来研究では,長方形の単純なモデルを扱っているが, 本研究では,実際の豚肝臓から形状を生成したものを用いる. 二点目は臓器の材料特性 を求めることにより,正常部と腫瘍の両方を 同定することである.以上の目的を達成するために,本論文では, ,(肝臓モデルの数値実験, ,( ファントムを用いた物理実験の二つの実験を実施する.以下に各実験の概要を示す.(1)肝臓モデルの数値実験仮想環境上で肝臓の有限要素モデルに対して外力を与え,予め仮定した材料特性を推定する.(2)ファントムを用いた物理実験提案する手法の妥当性を確認するために,ファントムに対して外力を与え,測定した材料特性と推定された材料特性を比較する.肝臓モデルの数値実験では,肝臓の材料特性を同定するために肝臓の有限要素モデルに粒子フィルタを利用したデータ同化を適用した.Mooney-Rivlinの超弾性モデルを利用し,5つの材料定数を推定した.肝臓の有限要素シミュレーションモデルに観測した変位データと肝臓の初期条件を定義し,状態空間モデルに対して不確実性を伴う部分に確率密度関数を加え,粒子フィルタを用いて予測・フィルタリングを行い,尤度関数を最大とするパラメータを推定値とした.予め定義した材料特性を推定する双子実験を行い,材料特性は予め定義した材料特性に収束したため,粒子フィルタを用いたデータ同化を臓器の材料特性同定に優れる手法として決定した. また,提案した手法の妥当性を確認するために,ファントムを使用した物理実験を実施した.臓器モデルとして,腫瘍を内包した直方体ファントムを利用し,正常部と腫瘍部(直径20[mm]の球体)で弾性率を変化させ,それぞれの弾性率を推定した.ファントムを変形させるために,球体で鉛直に押し込み,3つのロードセルで力を観測した.また,レーザ変位計で押し込み量の変位データを取得し,ファントムの変形・力データからシミュレーションと融合することで,弾性率を推定し,自動的に弾性率を逐次更新するシステムを構築した.本システムによって同定された弾性率とレオメータによって測定された弾性率を比較した.データ同化によって推定された弾性率は正常部で15.85[kPa],腫瘍部で58.50[kPa]となった.一方,測定された弾性率は正常部で16.61[kPa],腫瘍部で53.37[kPa]となった.正常部と腫瘍部でそれぞれ相対誤差は4.58[%],9.61[%]となった.

  • 螺旋折絆創膏による簡便な体内の封止システムの開発

    2019  

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    近年,内視鏡下外科手術は低侵襲な治療方法として注目されている.この手術では,身体に設置したトロッカーを介した内視鏡の視野下で,体内組織の治療やその後処置(組織接着,止血, 癒着防止等)を行う.通常の開腹手術では,可吸収性のシート剤を貼付することで簡便な後処置を行うことが多い.しかし,内視鏡下外科手術ではトロッカー内部の弁や作業空間の狭さから, シート剤を対象患部に送達するには工夫が求められる.代表的な工夫として,円筒状に丸めて小さく収納する方法,硬度のあるものと共に送達する方法等が挙げられる[1].しかし, 対象組織以外との接着の危険性や異物回収の必要性があり,確立された方法はない.そこで、本研究では,折り畳みによる体内貼付シートの収納を検討し, 優れた収納性と展開性を持つ内視鏡下外科手術での利用法を 提案することを目的とした.(1) 提案技法体内で対象組織以外との接着を防ぐには,効率の良い収納方法が望まれる.従来の円筒状に丸める方法では,円筒の高さ方向の収納ができない.そこで,全方向に収納可能な螺旋折を体内貼付シートに施すことを提案した.螺旋折りを施した膜面は,小さな円筒形状に収納され,両端を引張り展開する.螺旋折りを施した膜面の簡便な展開が可能な4 本脚アプリケータの設計をした.体内貼付シートを紙の内部に重ね折りして,アプリケータと紙を接続することで, 展開時にシートのみを分離することとした。&nbsp;(2) 展開実験と寸法最適化展開実験では,滑車に吊るした荷重によりアプリケータの糸に張力を付加して,4本脚及び体内貼付シートを展開させた. シートが紙から分離するときの展開率と引張力を測定した.体内貼付シートは可吸収性止血剤の SURGICEL®(Johnson &amp; Johnson)を使用した.螺旋折りを施す膜面の角数,収納した際の相対高さ,アプリケータの筒から展開部までの突出し長さを設計変数として実験計画法を実施した.得られた実験点に対して 625[mm2 ],1250[mm2],1875[mm2]の3種類の面積でそれぞれ3回の実験を行い,その平均を元に最適化を実施した.目的関数は収納体積,収納可能面積(筒の内径に収納できる面積の最大値),展開率,引張力,総突出し長さ(突出し長さと脚長を合わせた長さ) とした.展開実験の結果,収納体積と展開率・収納可能面積,引張力と総突出し長さの間にはそれぞれトレードオフの関係があった.そのため,それぞれを満足化する条件として四角形,相対高さ 34.0%,突出し長さ 23.0[mm]を選定した.この条件で展開実験を実施した結果,収納体積 538[mm3],展開率 69.8%,引張力 558[gf]を得た.応答曲面による予測値との誤差率はそれぞれ 1.76%,3.98%,2.88%であり,正常に応答曲面の近似と実験が実施されていることが確認できた.面積が 1875[mm2]の時の折り目と展開実験結果を以下に示す.体内貼付シートを螺旋折りにより収納し,4本脚アプリケータにより展開させる方法を提案した.優れた収納性と展開性を得るために,螺旋折りのパラメータとアプリケータの寸法を展開実験の結果によって最適化できた.

  • 螺旋折絆創膏の設計手法に関する研究

    2018   三浦智, パルケ・ビクター

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    近年,内視鏡下外科手術は低侵襲な治療方法として,身体に設置したトロッカーを介した内視鏡の視野下で,体内組織の治療やその後処置(組織接着,止血,癒着防止等)を行う.通常の開腹手術では,可吸収性のシート剤を貼付することで簡便な後処置を行うことが多い.しかし,内視鏡下外科手術ではトロッカー内部の弁や作業空間の狭さから,シート剤を対象患部に送達するには工夫が求められる. 本研究では,折り畳みによる体内貼付シートの収納を検討し,優れた収納性と展開性を持つ内視鏡下外科手術での利用法を提案することを目的とした.展開実験により、 螺旋折りを施す膜面の角数,収納した際の相対高さ,アプリケータの筒から展開部までの突出し長さを設計変数として実験計画法を実施した.得られた実験点に対して625[mm2 ], 1250[mm2],1875[mm2]の3種類の面積でそれぞれ3回の実験を行い,その平均を元に最適化を実施した.目的関数は収納体積,収納可能面積(筒の内径に収納できる面積の最大値),展開率,引張力,総突出し長さ(突出し長さと脚長を合わせた長さ) とした.&nbsp;

  • 金属スペースデブリの蒸発による非デブリ化

    2018   三浦智, パルケ・ビクター

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    宇宙空間に存在する構造物の非デブリ化を可能とする新たな技術を構築するものである。宇宙空間における高真空環境及び輻射熱入出力が支配する特徴を活かして、熱環境(断熱・輻射)を最大限に活用し、構造物の主要材料であるアルミニウムを気化温度へ到達させ、宇宙空間に放出するものである。地上においての既存技術を活用し以下のような検討を実施した。①非デブリ化対象衛星への熱源素子の取り付け方法の考案 機能停止した人工衛星は回転運動しており、その衛星を非デブリ化するための機器を設置する技術の考案及び好適の検討②高真空環境及び輻射熱入出力環境におけるアルミニウムの気化手順および条件の明確化 高真空環境において、太陽光にによる輻射熱入力を効果的に利用することによるエネルギを低減した加熱方法の検討③気化したアルミニウムの飛散管理手法の確立 宇宙空間において、構造物の破壊を生じさせないデブリの粒子寸法として粒径が0.1mm以下であるという基準を充足することが必要である。一方、この飛散粒子をイオン化して電場を通して加速することにより、イオンエンジンと同様の原理により推力を得ることができる。イオンエンジンを机上検討及び試作を実施し、発生させたイオン状アルミニウムによる効果を見積もった。

  • ラジオ波焼灼療法における力学特性を活用した柔軟針の穿刺操作と焼灼制御

    2016   三浦智

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    ラジオ波焼灼療法では,電極を患部付近に伸展させ通電させ,患部を焼灼する手技である.侵襲が少なく手術が可能であるものの,電極を的確な位置に配置することや通電する電力を的確に制御することが患部に位置する悪性細胞の焼灼の確率を高め,周辺の正常細胞の確保の確率が高まる.そこで,本研究では,(1)力学情報を用いた患部の位置同定,(2) 柔軟性を有する針を患部位置に到達させる力学的作用様式の検討,(3)針に通電させる電力の制御を目的として検討を進めた.

  • 超小型人工衛星WASEDA-SAT3の各種試験による性能評価

    2016  

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    超小型人工衛星WASEDA—SAT3の開発に際して,各種の試験を実施した.振動試験,熱真空試験,環境適合性試験を実施し,機能動作試験及び総合試験を実施した.このための運搬作業・学外試験場を利用した振動試験および試験による修繕・改良作業・成果公表などへの本支援を受けた.本衛星では,以下の2点において,新たな試みを実施している.一つは,パラボラ曲面のらせん折り様式による収納された膜面の展開実験であり,二つは,LCDパネルの稼働・非稼働による輻射熱流出量の制御の実験である.膜面の形状確認のため,小型プロジェクタ及びカメラを搭載し,公募映像を搭載している.JAXAへの受け渡しが完了し,ISSへの輸送あとに,ISSより放出された.

  • モデル予測制御法を用いた熱治療における組織凝固領域の状態推定アルゴリズムの導出

    2015   山川宏, 藤江正克

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    焼灼された生体組織の凝固に伴い硬化する特性に着目し,温度が異なる環境で粘弾性率を測定した.粘弾性率が急激に増加する境界温度が,肝臓の主要成分であるタンパク質の不可逆的変性温度に近く,粘弾性率が凝固の指標として有用性を確認した.焼灼条件の昇温速度が異なる場合組織の粘弾性率の温度依存性が異なった.さらに,生体組織の変性状態に応じたエネルギの導出を目的として生体組織の熱容量を用いて変性状態の推定手法を提案した.示差走査熱量測定を用いてラジオ波焼灼したブタ肝臓組織の熱容量の測定結果では電極針の近傍組織のみの熱容量の結果にピークが表れ,熱容量のピークの有無によって組織の可逆と不可逆的変性が判別できた.

  • 超小型人工衛星による薄膜展開構造の実証研究

    2015  

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    外形約12cm四方である超小型人工衛星の打ち上げが2016年度に予定している.衛星開発に必要な材料及び試験環境の構築を実施した.使用材料は米国軍事規格材料の使用が要求されており,一定の費用を充当し購入した後に衛星機体の製造を完了した.一方で,本衛星の重要な機能である直径約80cmの曲面らせん折り膜面の展開のため,真空環境試験環境の整備と試験を実施した.曲面らせん折り膜面はミウラ折りを発展させ,当研究室において改良が施されたものであり,宇宙空間での実証は世界初となるものである.また,LCDパネルを搭載し,熱輻射の入出力を制御する機能を有し,この点においても宇宙空間の実証は世界初となるものである.

  • 衝撃荷重が作用する縮小人体モデルの構築

    2013  

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    機械構造物が社会の中において重要な役割を果たし,多くの人間との接点を持つ状況で,機械が所望される機能と性能を実現するために,設計者は安全性を十分に考慮するようになっている。しかしながら,人間と機械の特性の相違が顕著となる衝撃荷重が作用する状況や一度に多くの人員が相互に接触する状況が発生し,座席等の機械設備とも力学的な相互作用を発現し,人体の損傷に影響する状況を十分に設計時に加味することは容易ではない.解析技術では計算規模が大きく,考慮すべき境界条件,荷重条件へロバストに適応する必要があり,計算負荷が高い.一方で,実験技術においては,実物が大きい場合には,その取扱いや実験の実施には多大な費用と時間が要する.従来の縮小モデルでの衝突事件で用いられた人体モデルは,衝突時の各身体部位の変形が考慮されていない簡易なモデルであった.そこで本研究では,相似則を用いて設計した人体ダミーモデルをラピッドプロトタイピングにより製作し,衝突時の応答特性の評価を行った.評価は側面衝突用ダミーの生態忠実性について記されたISOのテクニカルレポートTR9790(3)に従って行った.また,皮膚や筋肉を模擬した軟組織を付けたモデルに対して有限要素法解析によるダミー評価試験のシミュレーションを行い,ダミー胴体のリブの幅,胸部を覆う軟組織の厚み,軟組織の弾性係数を設計変数として応答波形の最適化を行った.最適化されたモデルを再びラピッドプロトタイピングにより製作し,評価実験を行うことで解析との整合性の確認と,生態忠実性の向上を確認した. 相似則を用いて縮小ダミーを設計・製作し,ISOのテクニカルレポートに従って胸部,腰部,腹部の生態忠実性の評価試験を行ったところ,ダミー全体で10点満点中4.615点,5段階評価にすると上から3番目の「Fair Biofidelity」という評価であった.部位ごとに見ると胸部の生態忠実性が特に低かったため,皮膚を模擬した軟組織を導入し,リブ幅,軟組織の厚み,軟組織の弾性係数を設計変数として解析による最適化を行った.その結果,胸部インパクト試験の応答波形の最大荷重を30.4%だけ応答目標に近づけることができた.また,ラピッドプロトタイピングで製作した最適化ダミーでも評価試験を行い,最適化前のモデルと比べて最大荷重が34.3%応答目標に近づいた. 以上より,人体ダミーモデルの定量的評価と,解析を用いた最適化による人体モデルの改善に成功した.

  • 初期設計段階における設計評価の統合に関する研究

    2013  

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    機械構造物の設計では、市場調査の後、概念設計、基本設計、詳細設計、生産設計などの段階を経て、その形状が決定されていく、さらに近年では、構造物の生産、消費、廃棄などの生産・消費活動における機械構造物の役割を十分に想定した設計が求められ、実際の市場評価と統合され製品設計にフィードバックされる。このように各種の事柄を精度よく想定することが必要となり、さらに、各種の事柄の同時成立性を考慮した唯一の製品を設計していくことが必要となる。このため、通常は構造物の特性は多くの事柄が密接に関連し、設計の評価は、多くの視点より多次元に評価されることになる。複数の評価尺度が適用される機械構造物の設計では、近年のリードタイムの短縮への要求に伴い、設計の初期段階である概念設計における精度の良い設計評価を実施することが設計手戻り低減にともなうリードタイム短縮を可能とし、さらに、円滑な設計工程の進捗に寄与するものと考えられる。そこで本研究では、設計者及び市場の満足度を考慮した設計支援法の構築を目的とする。平成25年度は、設計者の選好や顧客のニーズを含めた設計への満足度に影響する要因項目より満足度を算出する満足度関数(下図左)を定義する。これを利用した設計者の意思決定支援法(下図右)を改良・考案し、設計実験を実施し評価することを目的とし,車両構造物を対象として,以下の方法を提案し,計算実験を実施した.適用対象構造物として,車両構造物を選定し,その設計変数となる設計指標を選定した.車両構造物が有する機能構造および評価指標の明確化のため,Design Structure Matrix法により構造物が有する設計指標の関連を設計者による一対比較により明確にした。一般的には,設計指標は定量的に表現できるものが多く,その増減の場合を分け,関係性を明確にした.明確にされた構造をもとに,シグモイド関数関数を用い満足度関数を定式化した.車両構造物の性能評価には,非線形有限要素法を適用し導出し、衝突安全性の観点から,評価され定量化した。(4)多目的最適化手法による評価実験満足化トレードオフ法により,満足度関数を目的関数として,車両の構造設計問題ついて適用した.通常は物理量により直接に表現される目的関数により評価されパレート解が得られ,その後に,設計者の主観を活用した評価がなされる.この評価過程およびトレードオフ分析により,希求水準の試行錯誤が行われ,最終的な選好解が決定されていく.本研究での提案手法により,この試行錯誤が減少する効果が認めれた.

  • 医療画像からの力学情報の直接抽出と利用法の開発

    2011  

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    画面描写等に必要な計算処理を行う半導体集積回路であるGraphics Processing Unit(GPU)の計算能力は近年飛躍的に向上しており,今日では浮動小数点の計算速度ではCPUを大きく上回っている.このGPUの計算能力を画面描写以外の用途で用いることが試みられており,GPGPU(General Purpose computing on GPU)と呼ばれている.GPUは非常に多くのストリームプロセッサを持ち、並列処理でとても高い計算能力を持つ。このことから、動画のエンコーディングや音声処理、フーリエ変換などの並列度の高い計算においてGPGPUを適用することで計算速度を大きく向上させることができる。本研究では、CTやMRIなどの撮像装置より抽出した画像を格子状のセルとセル毎に定められた計算則からなる離散的計算モデルとして、直接に利用する計算法を構築した。すなわち、セルラ・オートマトン法(以下C.A.法)を利用した弾性体の解析手法を提案し、その演算の並列性に注目し、GPUによる高速演算による処理を可能とした。特に、本研究では、C.A.法を用いた粘弾性体のクリープ解析手法を提案し、更にCUDAに適用することで高速化を目指す。粘弾性の代表的なモデルとしてフォークトモデル(Voigt Model)とマクスウェルモデル(Maxwell Model)の2つが挙げられる。本研究ではクリープ解析挙動を表現することに適しているフォークトモデルとして定式化した。 C.A.法で使用する状態遷移式は解析対象を細分化した微小物体の運動を考えることで立式し、離散化することで導出することができ、解析対象の内部、表面などの境界条件によって遷移式を用意する必要がある。そのため、解析方法は基本的には弾性体の解析と同じであるが、粘性項を含むことにより変位の時刻暦応答依存を解き定式化した。C言語とCUDAにて作成したプログラムを用いて提案手法GPGPUによる解析結果、時間について考察した。GPGPUを適用することで、GPUのマルチプロセッサを生かした並列度の高い演算をすることができるようになる。立方体を模擬したセルに対して初期変位を与え、クリープ挙動を見る解析を行い、その際の解析時間と解析精度を比較した。C言語とCUDA双方の解析において、同様の結果を得ることが出来た。また、解析速度は、セル数が多く計算量が多くなるほどCUDAが高速という結果を得ることができ、提案手法の有効性を確認した。

  • オンライン同定法による力学情報統合システムの構築

    2010  

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    本研究は、材料特性の同定の精度を向上させるため、実際の臓器への力学的作用を明確にする実験中に取得した形状データを使用し、臓器の材料特性の更新を実現した同定法を検討するものである。本年度は、肺構造を対象にし、有限要素モデルの作成および準静的粘弾性解析や粘弾性解析などを実施し、材料特性、境界条件および肺構造のモデル化粒度との関連を実際の実験との整合性を考慮し調査した。また、解析手法として収縮要素を効率的に取り扱う方法についても検討を加えた。材料特性は肺胞や気管支の特性の中庸な特性で変形形状を表現できることが確認できた一方で、気管支構造の影響が高く表れる部位が明らかになり、モデル構築への指針を得ることができた。また、摩擦に関する境界条件は大きな影響を及ぼさないことが明らかになった。

  • FPGAを用いた粘弾性物質保持システムの構築

    2008  

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    近年,コンピュータの性能向上に伴い,大規模な有限要素モデルの取扱が可能となりつつあり,従来は計算が困難であった現象の解析や計算時間が短縮され,設計工程へ有限要素法を実装した机上シミュレーションソフトウエアの導入も進んでいる.コンピュータの基本性能の向上に加え,ハードウエアも進歩が見られ,例えば,グラフィックスハードウエアやFPGA(Field Programmable Gate Array)に作成したプログラムを転送し高速に実行できる環境が整いつつある.本研究では,有限要素法をFPGAを用いて高速に実行可能とすることを目的とし,特にロボットなどの動作機械におけるダイナミクスの推論エンジンとして活用することを視野に入れ,特に,ロボットアームにより取扱が困難である“やわらかい”物質の保持や移動を対象にした動作計画を支援するために,有限要素法による計算手順にリアルタイム性を実現できることを目標にアルゴリズム考案やシステム開発を実施し検証を行う.具体的には,(1)FPGA及びFPGA用プログラム開発コンパイラを購入し,運動方程式の求解アルゴリズムのいくつかを実装し計算時間を比較し,(2)既所有の摩擦測定装置を活用したロボットアーム先端及び保持部と粘弾性物質間の摩擦測定を実施する.(3)FPGAの並列性を活用する有限要素法及び時刻暦応答計算の実装方法を検討し実装を行うこととし,(1)運動方程式の求解アルゴリズムとしてRunge-Kutta法,Newmark-b法,Wilson-θ法をソフトウエアのみで実装し,そのなかからFPGAへの実装に適したアルゴリズムの選定を行った.この選定は,単純に移植するのみでは,その計算時間面にて不十分であるとの結論を踏まえて選定し,ルンゲクッタ法を対象とし,さらにルンゲクッタ法の状態行列を対角化し多元の状態更新式を並列に実行できるアルゴリズムを検討した.すなわち,並列化アルゴリズムとして実装することが必要との結論に至った.(2)摩擦測定装置により摩擦を測定し,速度依存項を同定し力学的境界条件の同定を行った.

  • グラフィックスハードウエアを用いた簡便な有限要素解析計算法の構築

    2006  

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    本研究は,従来はコンピュータの中央演算装置(CPU)が担っていた計算機能の一部をグラフィックハードウエア(GPU)を活用し計算効率を向上させることを目的としている.構造解析を対象とし,形状変化の運動方程式の求解と,材料配置に関する位相最適化問題を取り扱った.形状変化の運動方程式の求解については,3次元立体について,CPUのみ処理時間及び商用解析ソフトウエアとの比較検討を行い,約10倍の速度向上が明らかになった.また,材料配置に関する位相最適化問題については,2次元画像を対象に従来手法と同様な結果を得ることが確認できた.

  • グラフィックスハードウエアを用いた有限要素法の高度化に関する検討

    2005  

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    本研究は,従来はコンピュータの中央演算装置(CPU)が担っていた計算機能の一部をグラフィックハードウエア(GPU)を活用し計算効率を向上させることを目的としている.特に,構造解析問題を対象とし,与えられた荷重・境界条件より,2次元応力場における基礎式を充足する解を導出することになる.本研究では,この基礎式を満足するための計算法としてセルオートマトン理論を利用し,GPUで計算を可能とするデータ構造を提案し,実際に計算実験を行った.構造形態を示すデータは,その形状を表す画像データとして与え,その画像に境界条件,荷重条件を示す特異な画像を挿入することにより計算が可能となり,画像取得にはデジタルカメラなどの映像機器の利用が可能であることから利便性を有するものである.さらに,構造形状を決定するために従来より用いられている最適設計法の検討を試み,学会発表を行った.一方で,ハードウエアによる計算時間の短縮は近年のCPUの計算速度の向上に伴うことが考慮されるが,わずかながらの向上にとどまっている.一方で,3次元データへの拡張を試みた.ここでは,MRIで取得される積層画像を対象として,計算可能とするデータ構造を考案した.実装するにあたり,動的問題への拡張への必要性を認識し,その点を考慮しデータ構造を考案した.この部分に関しては,現在,計算実験中であり,その成果が得られ次第に発表を行う予定である.

  • エージェントベース協調設計法に関する研究及び協調設計システムの開発

    2001  

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    複数の設計者が複数の異なる技術分野に属するような複合領域における設計問題においては,競合した設計要求や設計指標の協調をはかり設計候補を絞ることが重要であることをまず指摘した.ここでは,技術領域が複合するために設計指標間の比較や単一化の困難が生じるために,単一化可能な合理的な評価尺度を構築するためにデータ包絡分析法を工学問題に適用する工夫を施した方法を提案した.さらに,設計者の妥協を形成するために妥協案を算出する方法を提案した.これらの提案した方法に加え,設計者の妥協状況を判定する方法を提案し組み合わせることにより,妥協のための各種の情報を設計者に提示する擬人的な設計者をスーパバイズエージェントとして,コンピュータネットワークを利用したシステムとして開発した.すなわち,コンピュータネットワークを介して設計問題を地理的に分散する設計者や解析ソフトウエアなどの人的および物的資源を統合したシステムを開発している.提示した設計案の評価方法により得た評価値を向上する設計案を設計者に提示するよう要求することにより,競合する設計者間が妥協する設計案が得られることが明らかになり,スーパバイズエージェントが提示する妥協案を参考とすることにより,設計者の妥協形成に寄与できることを明らかにした.さらに,交渉状態に応じた妥協情報の提示度合いを変化させることにより,特に設計初期における妥協する意志の無い状況における妥協情報の提示の抑制が可能なこと,妥協が進まなくなった状況の設計者に対する設計案に近い妥協案を提示することにより,さらに妥協を進めることができることが明らかにした.また,実際の設計を行う場合に有用である商用解析ソフトウエアと最適化アルゴリズムを接続するソフトウエア部品を開発し,商用解析ソフトウエアの利用が可能となるとともに,各種,最適設計システムの構築において利用可能であることを確認した.

  • 免疫エージェントによる最適設計に関する研究

    2000  

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     機械構造物の設計においては、複数の指標の向上を実現する設計解を、多くの制約条件を充足するように見出す必要がある。その設計解を求める手段として数理計画法が用いられている。一方、自然界に目を向けると、多くの制約が存在する自然環境において、多くの外的要因から生命の維持を実現している生命体が存在する。自然界における最適性を実現する仕組みとして、ほ乳類の持つ免疫機構が存在し、非常に多くの種類からなる抗原から、細胞体の維持を実現するために、抗体が大きな役割を果たしている。本研究では、この点に着目し、エージェント技術により、免疫機構をモデル化して、そのうち、抗原-抗体反応を利用して最適設計を行う方法として検討することを目的とする。ここでは、設計対象となる構造物の風荷重や地震などの外的要因を抗原と考え、部材配置や寸法などを内的要因として設計において定めるパラメータ(設計変数)を定める手法として、新たに提案した。いくつかの計算例によって、既存手法と比較することによりいくつかの点が明らかになった。(1)寸法最適化問題および位相最適化問題において、構造物の外的要因のうち、最も構造物の設計指標の悪化を最小限にとどめることができる設計案を導出できることがわかった。(2)多様な抗原に対する防御システムであるため、複数の極値を持つ多峰性の設計問題の場合においては、複数の局所的最適解を導出でき、単峰性の設計問題の場合には、最適解が求まることに加え、その周辺の解を導出でき、設計変更において、最適解が利用できず再計算を実行しない場合に、次善の解として利用できることがわかった。一方、計算中において設計候補の評価回数が多く必要となる欠点が認められた。この点を克服するために、(1)設計変数に関する目的関数や制約条件の感度を利用する種類の既存手法と組み合わせた計算法の構築や(2)応答局面法による近似的な局面生成技術を検討することが必要であると考えられ検討を加えている。

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Overseas Activities

  • 解析手法の高度化及びその応用に関する研究

    2011.03
    -
    2012.02

    マレーシア   (マラヤ大学)

    アメリカ   マサチューセッツ工科大学

 

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Teaching Experience

  • 加工学・実習

    早稲田大学  

  • 宇宙構造の設計と制御

    早稲田大学  

  • 宇宙科学技術

    早稲田大学  

  • 機械構造の最適化・満足化

    早稲田大学  

  • 振動工学

    早稲田大学  

  • 材料力学

    早稲田大学  

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