Updated on 2022/05/19

写真a

 
KANAI, Kenji
 
Affiliation
Faculty of Science and Engineering, Waseda Research Institute for Science and Engineering
Job title
Junior Researcher(Assistant Professor)

Concurrent Post

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

  • Faculty of Science and Engineering   School of Fundamental Science and Engineering

  • Faculty of Political Science and Economics   School of Political Science and Economics

Research Institute

  • 2020
    -
    2022

    国際情報通信研究センター   兼任研究員

Education

  • 2012
    -
    2015

    早稲田大学   基幹理工学研究科 情報理工学専攻   博士後期課程  

  • 2012
    -
    2015

    Waseda University  

  • 2012
    -
    2015

    Waseda University  

  • 2010
    -
    2012

    早稲田大学   基幹理工学研究科 情報理工学専攻   前期課程  

  • 2010
    -
    2012

    早稲田大学   基幹理工学研究科 情報理工学専攻   前期課程  

  • 2005
    -
    2010

    Waseda University   School of Science and Engineering  

▼display all

Degree

  • Waseda University   Doctor of Engineering

Research Experience

  • 2016
    -
    2018

    Tsuda University

  • 2016
    -
    2018

    Waseda University   Assistant Professor

  • 2014
    -
    2016

    Waseda University   Research Associate

  • 2013
    -
    2014

    Waseda University

Professional Memberships

  •  
     
     

    IEEE Tokyo Young Professionals

  •  
     
     

    IEEE ComSoc

  •  
     
     

    IEEE

  •  
     
     

    IPSJ

  •  
     
     

    IEICE

 

Research Areas

  • Information network

Research Interests

  • IoT, multimedia communication, mobile application, mobile networking, multimedia system

  • IoT, mobile network, mobile computing

Papers

  • IoT-centric service function chainingorchestration and its performance validation

    Hibiki Sekine, Kenji Kanai, Jiro Katto, Hidehiro Kanemitsu, Hidenori Nakazato

    2021 IEEE 18th Annual Consumer Communications and Networking Conference, CCNC 2021    2021.01

     View Summary

    In order to simplify deployment and management of IoT services, Network Function Virtualization (NFV) and Service Function Chaining (SFC) are promising solutions, and much researchers have conducted these topics. To enhance the reliability of former research efforts, in this paper, we propose an orchestration framework for IoT-centric SFC by using Docker and Kubernetes. The framework enables an automatic IoT service deployment by satisfying service requirements and computing and network resource constraints. In such deployment, we apply a Virtual Network Function (VNF)/Service Function (SF) placement problem to achieve efficient utilization of the resources. We set an objective function as minimizing both numbers of SF instances and communications and build a mathematical model based on Integer Linear Programming (ILP). To validate it, we implement a model for the framework and evaluate the performances by carrying out a numerical evaluation and a real experiment. From the evaluation results, we confirm that the proposed approach can reduce the number of SF placements and the number of communications among SF instances.

    DOI

  • Performance evaluations of channel estimation using deep-learning based super-resolution

    Daiki Maruyama, Kenji Kanai, Jiro Katto

    2021 IEEE 18th Annual Consumer Communications and Networking Conference, CCNC 2021    2021.01

     View Summary

    Thanks to breakthrough and evolution of deep learning in computer vision areas, adaptation of deep learning into communication systems are getting lots of attention to researchers. Recently, a channel estimation method by using a deep learning-based image super-resolution (SR) technique, namely ChannelNet, has been proposed. Inspired by this research, in this paper, we propose a deep SR based channel estimation method by applying more accurate deep learning-based SR network architecture, EDSR. In order to enhance intelligibility and reliability of deep SR based channel estimation methods, we evaluate the performance of several deep SR based channel estimation methods (SRCNN, ChannelNet and EDSR) by carrying out practical 5G simulations. From the evaluations, the results conclude that the deep SR based channel estimation methods can potentially improve accuracy of channel estimation and reduce BER characteristics.

    DOI

  • Road Crack Detection Using U-Net

    Naoki Wada, Kenji Kanai, Masaru Takeuchi, Jiro Katto

    2020 IEEE 9th Global Conference on Consumer Electronics, GCCE 2020     301 - 302  2020.10

     View Summary

    Recently, an efficient and automatic infrastructure maintenance service is mandatory. To address this demand, in this paper, we introduce a segmentation-based road damage detection method by using U-Net. To train the model, we collect 4K images by using a smartphone mounted on a bicycle and build our own road damage dataset. In addition, to improve detection accuracy, we apply focal loss and image patch for loss function and input image, respectively. From the evaluation, the result confirms that the method demonstrates to extract road damages with acceptable accuracy.

    DOI

  • Deep Pedestrian Distance Estimation from Single-shot Image

    Kazuki Murayama, Kenji Kanai, Masaru Takeuchi, Jiro Katto

    2020 IEEE 9th Global Conference on Consumer Electronics, GCCE 2020     276 - 277  2020.10

     View Summary

    In this paper, we propose a deep learning-based distance estimation method from a single-shot image. In the proposal, we model the estimation as a regression problem, and estimate the distance between a pedestrian and a camera by using three main features; size of bounding box, image blur and image features. By using KITTI dataset, we evaluate the accuracy of the proposed model.

    DOI

  • Accuracy evaluation of corridor width estimation using RGB-D camera

    Daiki Maruyama, Kenji Kanai, Jiro Katto

    2020 IEEE 9th Global Conference on Consumer Electronics, GCCE 2020     297 - 298  2020.10

     View Summary

    Recently, in order to build barrier-free smart cities, Japanese government is actively promoting to construct open data regarding roads and buildings, including existence of bumps, road slope and corridor width. To contribute this activity, in this paper, we introduce a corridor width estimation method by using an RGB-D camera. In this method, we assume that the RGB-D camera is mounted on the electric wheelchairs for a mobile sensing platform. The corridor width estimation is mainly operated by three steps: planes extraction, side walls extraction and distance calculation. We evaluate the accuracy of this method at eight corridors in Waseda University.

    DOI

  • Curb height estimation using 2DLiDAR mounted on e-bike

    Kento Yamamoto, Kenji Kanai, Jiro Katto

    2020 IEEE 9th Global Conference on Consumer Electronics, GCCE 2020     389 - 390  2020.10

     View Summary

    To contribute to publishing pedestrian networks as open data, this paper introduces a curb height estimation method by using 2DLiDAR mounted on e-Bike. We develop a prototype system by using e-Bike, 2DLiDAR and other sensors, and collect actual curb data around Waseda University. From accuracy evaluations, the results confirm that the prototype can estimate road level differences and positions with high accuracy.

    DOI

  • Light-weight video coding based on perceptual video quality for live streaming

    Yusuke Sakamoto, Shintaro Saika, Masaru Takeuchi, Tatsuya Nagashima, Zhengxue Cheng, Kenji Kanai, Jiro Katto, Kaijin Wei, Ju Zengwei, Xu Wei

    Proceedings - 2018 IEEE International Symposium on Multimedia, ISM 2018     139 - 142  2019.01

     View Summary

    In video streaming on the internet, effective encoding recipes (i.e. bitrate-resolution pairs) are a main obstacle to deliver high-quality video streams. We developed a method to generate an encoding recipe that considers subjective visual quality with one just-noticeable difference (JND) distance. However, this method requires excessive computation time, which is not directly applicable for live streaming. In this paper, in order to provide a light-weight method for live streaming, we developed three acceleration techniques: resolution extrapolation, VMAF skipping and sampled objective measure calculation. These techniques are heuristic, but greatly contribute to reducing computational cost. Experimental results demonstrate that the proposed method achieves a significant reduction in computation time without significant effects on rate-JND characteristics.

    DOI

  • Evaluation of Throughput Prediction for Adaptive Bitrate Control Using Trace-Based Emulation

    Bo Wei, Hang Song, Shangguang Wang, Kenji Kanai, Jiro Katto

    IEEE Access, Vol.7, pp.51346-51356, Apr.2019.   7   51346 - 51356  2019  [Refereed]

     View Summary

    Dynamic adaptive video streaming over HTTP (DASH) is widely studied and has been adopted in modern video players to ensure user quality of experience (QoE). In DASH, adaptive bitrate control is a key part whose ultimate goal is to maximize video bitrate while minimizing rebuffering. Throughput prediction plays an important role in helping select the proper video bitrate dynamically. In this paper, we studied the influence of throughput prediction on adaptive video streaming. Because the real-world network is dynamic, different methods need to be tested with large-scale deployments and analyzed statistically. However, this is difficult in academic research. Therefore, we established a reproducible trace-based emulation environment, which enables us to compare different methods quantitatively under the artificially same condition, with limited experiments. The throughput prediction methods are implemented into DASH to evaluate the effect on QoE for video streaming. The results indicate that the prediction method using long short-term memory (LSTM) performs better than the other methods. However, throughput prediction alone is not enough to ensure high QoE. To further improve the QoE, we proposed the decision map method (DMM), where the buffer occupancy is also incorporated to make a selection. By using this decision map, the choice of bitrate can be smarter than that when only prediction information is used. The total QoE is further improved by 32.1% in the ferry trace, which shows the effectiveness of DMM in further improving the performance of throughput prediction in adaptive bitrate control.

    DOI

  • Methods for Adaptive Video Streaming and Picture Quality Assessment to Improve QoS/QoE Performances

    Kenji Kanai, Bo Wei, Zhengxue Cheng, Masaru Takeuchi, Jiro Katto

    IEICE Trans. on Comm., July 2019   E102B ( 7 ) 1240 - 1247  2019  [Refereed]  [Invited]

     View Summary

    This paper introduces recent trends in video streaming and four methods proposed by the authors for video streaming. Video traffic dominates the Internet as seen in current trends, and new visual contents such as UHD and 360-degree movies are being delivered. MPEG-DASH has become popular for adaptive video streaming, and machine learning techniques are being introduced in several parts of video streaming. Along with these research trends, the authors also tried four methods: route navigation, throughput prediction, image quality assessment, and perceptual video streaming. These methods contribute to improving QoS/QoE performance and reducing power consumption and storage size.

    DOI

  • Throughput Prediction Using Recurrent Neural Network Model

    Bo Wei, Mayuko Okano, Kenji Kanai, Wataru Kawakami, Jiro Katto

    2018 IEEE 7th Global Conference on Consumer Electronics, GCCE 2018     88 - 89  2018.12

     View Summary

    To ensure good quality of experience for user when transmitting video content, throughput prediction can contribute to the selection of proper bitrate. In this paper, we propose a throughput prediction method with recurrent neural network (RNN) model. Experiments are conducted to evaluate the methods, and the results indicate that proposed method can decrease the prediction error by a maximum of 29.39% compared with traditional methods.

    DOI

  • Proactive Interest Adaptation and Content Caching for Adaptive Bit-Rate Video Streaming over NDN

    Suphakit Awiphan, Kanin Poobai, Kenji Kanai, Jiro Katto

    2018 3rd International Conference on Computer and Communication Systems, ICCCS 2018     187 - 191  2018.09

     View Summary

    Named Data Networking (NDN) has been recently introduced as a new network architecture. The implementation of adaptive bit-rate video streaming on NDN is one of the most challenging tasks. The in-network caching feature of NDN could mislead a consumer to overestimate the end-to-end throughput for the next video segment. In this paper, we propose a strategy for more efficient rate adaptation by allowing Interest message adaptation in a hop-by-hop fashion. Moreover, the proactive content caching is designed to be utilized on the related router when a bottleneck on the transmission path was detected. The experiments using NDN-JS and DASH-JS demonstrate that our proposed solution provides better average stream bit-rate than the traditional rate adaptation method. Also, the link bandwidth consumption for video data transmission using the proposed scheme could be reduced efficiently.

    DOI

  • TRUST: A TCP Throughput Prediction Method in Mobile Networks

    Bo Wei, Wataru Kawakami, Kenji Kanai, Jiro Katto, Shangguang Wang

    IEEE Globecom 2018, Dec.2018.    2018  [Refereed]

     View Summary

    Throughput prediction is essential for ensuring high quality of service for video streaming transmissions. However, current methods are incapable of accurately predicting throughput in mobile networks, especially for moving user scenarios. Therefore, we propose a TCP throughput prediction method TRUST using machine learning for mobile networks. TRUST has two stages: user movement pattern identification and throughput prediction. In the prediction stage, the long short-term memory (LSTM) model is employed for TCP throughput prediction. TRUST takes all the communication quality factors, sensor data and scenario information into consideration. Field experiments are conducted to evaluate TRUST in various scenarios. The results indicate that TRUST can predict future throughput with higher accuracy than the conventional methods, which decreases the throughput prediction error by maximum 44% under the moving bus scenario.

    DOI

  • Overview of multimedia mobile edge computing

    Kenji Kanai, Kentaro Imagane, Jiro Katto

    ITE Transactions on Media Technology and Applications   6 ( 1 ) 46 - 52  2018  [Refereed]  [Invited]

     View Summary

    Recently, to provide a low-latency mobile computing platform, Mobile Edge Computing (MEC) is proposed. In this paper, we first summarized the feature capabilities of MEC, such as content distribution and caching, computational offloading and multimedia Internet of Things (IoT). Then, to understand recent research efforts of multimedia MEC, we briefly highlight the research efforts in terms of above three capabilities: how to achieve edge caching in video distribution, how to schedule computational offloading to the cloud and how the communication quality degradation affects to the user experience of multimedia IoT. Finally, we addressed the emerging research issues of multimedia MEC to improve reliability and robustness of multimedia MEC.

    DOI

  • [奨励講演]通信速度変動を考慮した省電力配信のための消費電力推定モデルの特性評価

    竹中幸子, 金井謙治, 甲藤二郎, 村瀬勉

    電子情報通信学会ICM研究会   ICM2016-63 ( 507 ) 57-62  2017.03

  • Adaptive Video Streaming in Hybrid Landslide Detection System with D-S Theory

    Zhi Liu, Kenji Kanai, Masaru Takeuchi, Toshitaka Tsuda, Hiroshi Watanabe

    2017 IEEE INTERNATIONAL CONFERENCE ON SMART COMPUTING (SMARTCOMP)     352 - 357  2017

     View Summary

    Disaster detection is an important research topic and draws great attentions from both industry and academia. In this paper, we study the hybrid landslide detection system, which utilizes the video surveillance camera and multiple kinds of sensors and can detect the landslide automatically. Edge processing is adopted in this hybrid system to fuse the sensor data based on the Dempster-Shafer (D-S) theory, i.e. utilizing multiple sensors' information to calculate the possibility of the landslide. Edge processing can make faster decisions than the control center, the results of the edge processing are then used to schedule the sensor's transmission frequency and video transmission under the network constraints in this system. The simulation results show that the proposed scheme outperforms the competing schemes in typical network scenarios.

  • HISTORY-BASED THROUGHPUT PREDICTION WITH HIDDEN MARKOV MODEL IN MOBILE NETWORKS

    Bo Wei, Kenji Kanai, Jiro Katto

    2016 IEEE INTERNATIONAL CONFERENCE ON MULTIMEDIA & EXPO WORKSHOPS (ICMEW)    2016

     View Summary

    Throughput prediction contributes a lot to adaptive bitrate control, adjusting the quality of video streaming accordingly to offer smooth media transmission and save energy at the same time. To solve the problem of throughput prediction for real time communication, this paper puts forward a new history-based throughput prediction method applying Hidden Markov Model in mobile networks. The main purpose of this method is to predict future throughput for real time communication in mobile network. Our novel approach utilizes Hidden Markov Model (HMM) with Gaussian Mixture Model (GMM) to deal with history time series of throughput and judge fluctuation factor with total variance when predicting future throughput. By conducting experiments with the new methodology, we compare the accuracy of the proposed method with three other conventional prediction methods. Results show our proposed method could identify data fluctuation effectively and predict future 100s throughput with high accuracy in various situations.

  • Evaluation and Analysis of System Latency of Edge Computing for Multimedia Data Processing

    Kentaro Imagane, Kenji Kanai, Jiro Katto, Toshitaka Tsuda

    2016 IEEE 5TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS    2016

     View Summary

    In order to analyze system latency of edge computing for multimedia data processing, we propose a model of system latency of two different distributed processing scenarios: pipeline and parallel processing. We validate the model by using actual cloud services and human detection processing.

  • Quality Evaluations of 8K/60P UHDTV Retransmission for a Broadcasting and Communication Integrated Platform

    Rintaro Harada, Shintaro Saika, Masaru Takeuchi, Kenji Kanai, Jiro Katto, Yasutaka Matsuo

    PROCEEDINGS OF 2016 IEEE INTERNATIONAL SYMPOSIUM ON MULTIMEDIA (ISM)     111 - 112  2016

     View Summary

    In this study, we propose a broadcasting and communication integrated platform that can retransmit 8K broadcasting contents from a TV receiving set to mobile devices. We then evaluate the QoS characteristics and the qualities of 8K contents in this platform. Evaluation results conclude that 8K broadcasting contents can be retransmitted to mobile devices smoothly and their qualities are nearly as high as those of assumed 8K broadcasting service in Japan.

    DOI

  • A Highly-Reliable Buffer Strategy Based on Long-Term Throughput Prediction for Mobile Video Streaming

    Kenji Kanai, Konishi Hidenori, Yuya Ishizu, Jiro Katto

    2015 12TH ANNUAL IEEE CONSUMER COMMUNICATIONS AND NETWORKING CONFERENCE     677 - 682  2015

     View Summary

    Providing robust video streaming along with efficient wireless resource usage is necessary for mobile users, especially on subway, and mobile carriers. To achieve this, we propose a highly-reliable buffer strategy based on long-term throughput prediction. Our approach has two elements which are called "long-term throughput prediction" and "guaranteed playout buffer filling mechanism." To avoid any video freeze due to network quality degradation, our approach calculates the optimal amount of playout buffer and schedules video download timing in a theoretical manner. We evaluate its performance via experiments in real environment. Evaluations conclude that our approach can provide highly-reliable video streaming and also achieve to reduce the average playout buffer size on the client.

  • Implementation Evaluation of Proactive Content Caching using DASH-NDN-JS

    Takeshi Muto, Kenji Kanai, Jiro Katto

    2015 IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE (WCNC)     2239 - 2244  2015

     View Summary

    Proactive content caching scheme utilizing transportation systems, especially on trains, was proposed in order to provide a robust content delivery with efficient wireless resource usage. This system requires content servers with NDN capability to be placed on every station and trains. The mechanism is to pre-cache the contents that users request to the station server before the train arrives, and the train server caches the content during its stoppage time. With this mechanism, users are able to have a continuous playback of videos while riding on trains. In this paper, we have proposed a browser-based implementation, called DASH-NDN-JS, for this proactive content caching scheme. We evaluate this scheme, and experiment with multiple users to see how it will affect the video quality each user will achieve and the bandwidth consumption between the connections. Our evaluations conclude that the increase of users lowers the video quality, but avoids congestion depending on what video content each user will want to request.

  • QoS Improvement of Mobile 4K Video by Using Radio Quality Map

    Sakiko Takenaka, Kenji Kanai, Jiro Katto

    2015 IEEE 4TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)     541 - 542  2015

     View Summary

    Effective use of various wireless network interfaces is expected. In this paper, we evaluate Quality of Service characteristics of mobile 4K video using a radio communication quality map. We collect radio communication quality (e.g. throughput) by smartphones and visualize the quality in a heat map. Using this map, we select two routes that are expected to bring the highest and the lowest communication quality. We then evaluate QoS characteristic of 4K video streaming using MPEG-DASH on these two routes. The result shows that a good route user can achieve 1.5 times higher communication quality than a bad route user.

  • Evaluations of 4K/2K Video Streaming Using MPEG-DASH with Buffering Behavior Analysis

    Rintaro Harada, Kenji Kanai, Jiro Katto

    2015 IEEE 4TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)     539 - 540  2015

     View Summary

    In this paper, we evaluate performances of 4K/2K video streaming using DASH-JS over 2.4/5GHz WiFi networks. We confirmed that fluctuation of reception quality was mainly caused by the minimum representation rate of MPEG-DASH contents and overlapped ON cycles for packet transmission.

  • Energy-Efficient Video Streaming over Named Data Networking using Interest Aggregation and Playout Buffer Control

    Yuya Ishizu, Kenji Kanai, Jiro Katto, Hidenori Nakazato, Marie Hirose

    2015 IEEE INTERNATIONAL CONFERENCE ON DATA SCIENCE AND DATA INTENSIVE SYSTEMS     318 - 324  2015

     View Summary

    In wireless networks, it is important to realize energy-efficient video delivery. To do this, we introduce energy-efficient video streaming over named data networking (NDN). In our proposed approach, we focus on two areas, namely, to improve the throughput performance by Interest aggregation, and to reduce the overhead energy using playout buffer-size control. We evaluate the power savings realized by our method using a hardware power-measurement tool. Our results show that Interest aggregation can realize an approximately 50% reduction in energy compared to conventional NDN implementation, and a large playout buffer size can reduce the energy by approximately 37% compared to the case of a small playout buffer size.

    DOI

  • Energy Consumption Evaluation of ICN Toward Power-Saving Video Delivery

    Daiki Aoki, Sakiko Takenaka, Kenji Kanai, Jiro Katto, Hidenori Nakazato, Marie Hirose

    2015 IEEE INTERNATIONAL CONFERENCE ON DATA SCIENCE AND DATA INTENSIVE SYSTEMS     390 - 395  2015

     View Summary

    Information Centric Networking (ICN) is a new networking paradigm in which the network provides users with named content, instead of communication channels between hosts. However, many issues, such as naming, routing, resource control, and security, still need to be resolved before it can be realized practically. Further, the energy efficiency of ICNs has not been sufficiently considered. In this study, we evaluate the energy consumption of an ICN network by first measuring the power consumption of actual PCs/smartphones and constructing an energy consumption model. Then, by using the model and the simulator ndnSIM, we calculate the energy consumed by the network. We also evaluate the energy consumed for video delivery, with a view toward power-saving video delivery.

    DOI

  • Content Offloading System on CCN Architecture utilizing Transportation Systems

    Hiroto Kisara, Sayo Kurokawa, Kenji Kanai, Jiro Katto

    2015 IEEE GLOBECOM WORKSHOPS (GC WKSHPS)    2015

     View Summary

    In order to tackle recent mobile traffic explosion, content offloading using Wifi access points from cellular network is deployed but the Wifi system itself is sometimes heavily congested. In this paper, we propose a content offloading system using transportation systems such as a train. In addition, we aim to incorporate CCN (Content Centric Networking) into our system to exploit its in-network caching capability. We compare three protocol designs, pure IP, IP+CCN hybrid and pure CCN, and show the efficiency of our system using a network simulator.

  • Performance Evaluation of Proactive Content Caching for Mobile Video through 50-User Field Experiment

    Kenji Kanai, Takeshi Muto, Jiro Katto, Wataru Kameyama, Yong-Jin Park, Takuro Sato, Shinya Yamamura, Tomoyuki Furutono, Takafumi Saito, Hirohide Mikami, Kaoru Kusachi, Toshitaka Tsuda

    2015 IEEE GLOBECOM WORKSHOPS (GC WKSHPS)    2015

     View Summary

    Providing robust content delivery service, such as Video on Demand, with efficient wireless resource usage is important for mobile users. To achieve this, we have proposed a proactive content caching scheme utilizing transportation systems (e.g., train). Because our previous prototype is immature and has a scalability issue, in this paper, we introduce an efficient transmission mechanism of Interest messages to improve throughput efficiency in mobile NDN, develop two prototypes based on NDN and HTTP, and then evaluate prototype performances by performing larger-scale field experiments on actual commercial railroad line. Evaluations conclude that our system can achieve high efficient content transfer and fully utilize wireless network bandwidth. As a result, our system can provide high-quality video streaming for up to 50 users simultaneously.

  • Performance Analysis and Validation of High QoS Route Navigation for Mobile Users

    Kenji Kanai, Jiro Katto, Tutomu Murase

    2014 16th Asia-Pacific Network Operations and Management Symposium (APNOMS)    2014

     View Summary

    Improving Quality of Service (QoS) in wireless networks is important and necessary for mobile users. We have previously proposed Comfort Route (CR) Navigation, which navigates users to their destinations using high QoS communication areas, such as Wi-Fi APs, rather than the geographical Shortest Route (SR). In this paper, we employ an analytical model to estimate the CR gain in a theoretical manner which assumes that available cellular and Wi-Fi throughputs are uniform within their coverage. The CR gain is computed by using basic parameters, including wireless network bandwidth and transmission time. To validate our model, we compare simulation results and real observation. These results conclude that the CR gain could estimate by using our analytical model.

  • Improvement of Throughput Prediction Accuracy for Video Streaming in Mobile Environment

    Hidenori Konishi, Kenji Kanai, Jiro Katto

    2014 IEEE 3RD GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)     749 - 750  2014

     View Summary

    With the increasing demand for video streaming in mobile environment, we have been tackling a research on throughput prediction based on the measurement history data in order to improve service quality[1][2]. Since throughput fluctuation occurs sharply in mobile environment, useless packet loss or congestion occurs when available network bandwidth is insufficient compared to the bit rate of video contents. Hence, it is possible to improve the quality of service by deducing the available throughput and selecting appropriate bit rate for the video contents. In this paper, we propose a throughput prediction method that considers mobile locations of a train and their throughput history and show promising experimental results.

  • Comfort Route Navigation Providing High Communication Quality and Energy Saving for Mobile Devices

    Kenji Kanai, Hidenori Konishi, Jiro Katto, Tutomu Murase

    2014 IEEE 3RD GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)     547 - 548  2014

     View Summary

    Extending battery life for smartphones while using wireless networks is important. In this paper, we propose Comfort Route for Energy Saving (CRFES), which helps users extend the battery life of their smartphones by navigating to their destinations via Quality of Service (QoS)-compliant energy-efficient spots such as Wi-Fi spots. To create CRFES, we construct maps of Wi-Fi spots using logging software we developed for Android phones. In addition to locations, we record actual throughput and energy consumption observed in cellular/Wi-Fi networks. So comfort route navigation is done by choosing a route which minimizes energy consumption instead of choosing the shortest path. Evaluations are carried out by computer simulation and one real city map. The results conclude that CRFES can save the battery life by approximately 50% by spending 1.6 times time cost to reach their destinations on average.

  • Proactive Content Caching utilizing Transportation Systems and its Evaluation by Field Experiment

    Kenji Kanai, Takeshi Muto, Hiroto Kisara, Jiro Katto, Toshitaka Tsuda, Wataru Kameyama, Yong-Jin Park, Takuro Sato

    2014 IEEE GLOBAL COMMUNICATIONS CONFERENCE (GLOBECOM 2014)     1382 - 1387  2014

     View Summary

    Providing robust content delivery along with efficient wireless resource usage is important for next generation wireless networks. To achieve this, we propose a proactive content caching scheme utilizing transportation systems, especially trains. In our system, we place content servers with CCN capability to every train and station. Segments of video contents are pre-cached by the station servers before trains arrive at stations. Trains receive the contents via high-speed wireless transport while they stop at the stations. We develop a prototype system based on IP and CCN Hybrid protocols. We evaluate its performance by field experiment and compare with traditional CDN scenarios using cellular networks. Evaluations conclude that our system can achieve high-speed and high-reliable video delivery without freezing.

  • Performance Evaluations of Comfort Route Navigation Providing High-QoS Communication for Mobile Users

    Kenji Kanai, Jiro Katto, Tutomu Murase

    ITE Transactions on Media Technology and Applications   2 ( 4 ) 327 - 335  2014  [Refereed]

     View Summary

    To improve Quality of Service in wireless networks while mobile users travel, we introduce Comfort Route Navigation (CRN) which is a navigation system based on a user centric mobility management for next generation wireless networks. CRN provides an optimal route that satisfies user needs, such as obtaining maximum wireless resources. To achieve CRN, we construct an access point (AP) map of Shinjuku city. To reflect quality of APs in this map, we evaluate throughputs at seven public Wi-Fi spots. Based on these observations, we evaluate performance of our CRN via computer simulations and in a real environment. These evaluations conduct that a CRN user could obtain higher communication quality rather than a Shortest Route (SR) user. These evaluations also conclude that CRN gain depends heavily on the quality and location of the best broadband spot.

    DOI

  • QoS characteristics on a longcut route with various radio resource models

    Kenji Kanai, Yuri Akamatsu, Jiro Katto, Tutomu Murase

    2012 IEEE International Conference on Pervasive Computing and Communications Workshops, PERCOM Workshops 2012     419 - 422  2012

     View Summary

    Previous our research has introduced an optimal longcut route problem and a number of solutions to this problem. However, to date, the literature has only presented evaluations based on a single theoretical radio propagation model. Because throughput characteristics derived from radio propagation models significantly affects longcut route performance, this study introduces three simple models by referring to actual measurement values. The results of our evaluation show that there are large differences in performance between the three models. The Non-Line-of-Sight model can have an improvement ratio approximately five times greater than that of the Line-of-Sight Indoor model and six times greater than that of the previous theoretical model. © 2012 IEEE.

    DOI

  • Implementation and Performance Evaluations of Adaptive Rate Control Mechanisms in VIC

    Kenji Kanai, Masaru Takeuchi, Jiro Katto

    Workshop on Picture Coding and Image Processing 2010, Dec.2010.  

  • Evaluation of MPEG-DASH over CCNx over different TCPs

    Takeshi Muto, Wang Wu, Suphakit Awiphan, Kenji Kanai, Jiro Katto

    Packet Video Workshop 2013, Dec.2013.  

  • Performance Evaluations of Edge Computing for Multimedia Data Processing

    Kentaro Imagane, Kenji Kanai, Jiro Katto

    IEICE SISA 2016, Sep.2016.  

  • Green Video Delivery System using Moving Route Navigation and Playout Buffer Control

    Sakiko Takenaka, Kenji Kanai, Jiro Katto, Tutomu Murase

    IEEE CCNC 2017, Jan.2017.  

  • QoS and QoE Evaluations of 2K and 4K Video Distribution Using MPEG-DASH,

    Tatsuya Nagashima, Kenji Kanai, Jiro Katto

    IEEE GCCE 2017, Oct.2017.  

  • Accuracy Evaluations of Human Moving Pattern Using Communication Quality Based on Machine Learning,

    Wataru Kawakami, Kenji Kanai, Bo Wei, Jiro Katto

    IEEE GCCE 2017, Oct.2017.  

  • Image Quality Evaluations of Image Enhancement Under Various Encoding Rates for Video Surveillance System

    Airi Sakaushi, Kenji Kanai, Jiro Katto, Toshitaka Tsuda

    IEEE GCCE 2017, Oct.2017.  

  • QoS and QoE Evaluations of 2K and 4K DASH Contents Distributions

    Tatsuya Nagashima, Kenji Kanai, Jiro Katto

    IEEE IMAD 2017, Dec.2017.  

  • A History-based TCP Throughput Prediciton Incorporating Communication Quality Features by Support Vector Regression for Mobile Network

    Bo Wei, Wataru Kawakami, Kenji Kanai, Jiro Katto

    IEEE ISM 2017, Dec.2017.  

  • Edge-centric Field Monitoring System for Energy-efficient and Network-friendly Field Sensing

    Keigo Ogawa, Kenji Kanai, Masaru Takeuchi, Jiro Katto, Toshitaka Tsuda

    IEEE EdgeCom 2018, Jan.2018.  

  • Performance Evaluations of Multimedia Service Function Chaining in Edge Cloud

    Kentaro Imagane, Kenji Kanai, Jiro Katto, Toshitaka Tsuda, Hidenori Nakazato

    IEEE CCNC 2018, Jan.2018.  

  • Edge-centric Video Surveillance System Based on Event-driven Rate Adaptation for 24-hour Monitoring

    Airi Sakaushi, Kenji Kanai, Jiro Katto, Toshitaka Tsuda

    IEEE PerFoT 2018, Mar.2018. (to be published)  

  • Performance Evaluations of Software-Defined Acoustic MIMO-OFDM transmission

    Airi Sakaushi, Mayuko Okano, Kenji Kanai, Jiro Katto

    IEEE WCNC 2018, Apr.2018. (to be published)  

  • Perceptual Quality Driven Adaptive Video Coding Using JND Estimation,

    Masaru Takeuchi, Shintaro Saika, Yusuke Sakamoto, Tatsuya Nagashima, Zhengxue Cheng, Kenji Kanai, Jiro Katto, Kaijin Wei, Ju Zengwei, Xu Wei

    PCS 2018, June.2018.    [Refereed]

  • A Fast No-Reference Screen Content Image Quality Prediction using Convolutional Neural Networks

    Zhengxue Cheng, Masaru Takeuchi, Kenji Kanai, Jiro Katto

    IEEE MLAI Workshop in ICME 2018, July 2018.    [Refereed]

  • Machine Learning based Transportation Modes Recognition using Mobile Communication Quality

    Wataru Kawakami, Kenji Kanai, Bo Wei, Jiro Katto

    IEEE ICME 2018, July 2018.    [Refereed]

  • Accuracy Evaluations of Contact-Free Heart Rate Measurement Methods Using 4K Facial Images

    M.Yasumaru, Z.Cheng, R.Yokoyama, K.Kanai, J.Katto

    IEEE ICCE 2019, Jan.2019.    [Refereed]

  • IoT Device Virtualization for Efficient Resource Utilization in Smart City IoT Platform

    Keigo Ogawa, Kenji Kanai, Kenichi Nakamura, Jiro Katto, Hidenori Nakazato

    IEEE PerCom 2019, WiP, Mar.2019.    [Refereed]

  • TCP throughput characteristics over 5G millimeter-wave network in an indoor train station

    Mayuko Okano, Yohei Hasegawa, Kenji Kanai, Bo Wei, Jiro Katto

    IEEE WCNC 2019, Apr.2019.    [Refereed]

  • Performance Evaluations of IEEE 802.11ad and Human Pose Detection towards Intelligent Video Surveillance System

    Mayuko Okano, Kenji Kanai, Jiro Katto

    IEEE 2019 ICCE-TW, May.2019.    [Refereed]

  • Performance Evaluations of Tile-based 360-degree DASH Streaming with Clustering-based Viewport Prediction

    Yuya Shinohara, Satomi Shirasaki, Yiyan Wu, Kenji Kanai, Jiro Katto

    IEEE 2019 ICCE-TW, May.2019.    [Refereed]

  • Performance Evaluations of IoT Device Virtualization for Efficient Resource Utilization

    Keigo Ogawa, Hibiki Sekine, Kenji Kanai, Kenichi Nakamura, Hidehiro Kanemitsu, Jiro Katto, Hidenori Nakazato

    2019 Global IoT Summit, Jun.2019.    [Refereed]

  • A Function Clustering Algorithm for Resource Utilization in Service Function Chaining,

    Hidehiro Kanemitsu, Kenji Kanai, Jiro Katto, Hidenori Nakazato

    IEEE CLOUD 2019, July 2019.    [Refereed]

  • Road Infrastructure Monitoring System using E-Bikes and Its Extensions for Smart Community

    Jiro Katto, Masaru Takeuchi, Kenji Kanai, Heming Sun

    SMAS 2019, ACM Mobicom Workshop, Oct. 2019.    [Refereed]

  • Performance Evaluations of Viewport Movement Prediction and Rate Adaptation for tile-based 360-degree Video Delivery

    Yuya Shinohara, Kenji Kanai, Jiro Katto

    IEEE ISM 2019, Dec.2019.    [Refereed]

  • Field Experiments of 28 GHz Band 5G System at Indoor Train Station Platform

    Mayuko Okano, Yohei Hasegawa, Kenji Kanai, Bo Wei, Jiro Katto

    IEEE CCNC 2020, Jan.2020.    [Refereed]

  • Proactive Content Caching for Mobile Video utilizing Transportation Systems and Evaluation through Field Experiments

    Kenji Kanai, Takeshi Muto, Jiro Katto, Shinya Yamamura, Tomoyuki Furutono, Takafumi Saito, Hirohide Mikami, Kaoru Kusachi, Toshitaka Tsuda, Wataru Kameyama, Yong-Jin Park, Takuro Sato

    IEEE JSAC, Vol.234, Issue. 8, pp.2102-2114, Aug. 2016.    [Refereed]

  • Intelligent Video Surveillance System Based on Event Detection and Rate Adaptation by Using Multiple Sensors

    Kenji Kanai, Keigo Ogawa, Masaru Takeuchi, Jiro Katto, Toshitaka Tsuda

    IEICE Communication, Vol.E101-B, No.3, Mar.2018    [Refereed]

  • HOAH: A Hybrid TCP Throughput Prediction with Autoregressive Model and Hidden Markov Model for Mobile Networks

    Wei Bo, Kenji Kanai, Wataru Kawakami, Jiro Katto

    IEICE Communication, Vol.E101-B, No.7, Jul.2018    [Refereed]

  • Energy-efficient Mobile Video Delivery utilizing Moving Route Navigation and Video Playout Buffer Control

    Kenji Kanai, Sakiko Takenaka, Jiro Katto, Tutomu Murase

    IEICE Communication, Vol.E101-B, No.7, Jul.2018    [Refereed]

  • A Fully-blind and Fast Image Quality Predictor with Convolutional Neural Networks

    Zhengxue Cheng, Masaru Takeuchi, Kenji Kanai, Jiro Katto

    IEICE Trans. on Fundamentals Vol.E101-A, No.9, pp.1557-1566, Sep.2018.    [Refereed]

  • A highly accurate transportation mode recognition using mobile communication quality

    Wataru Kawakami, Bo Wei, Kenji Kanai, Jiro Katto

    IEICE Trans. on Comm. Vol.E102-B, No.4, pp.741-750, Apr. 2019.    [Refereed]

▼display all

Misc

  • Performance Evaluations of Feedback Control Framework Using IoMT Edge Computings (モバイルネットワークとアプリケーション)

    小川 啓吾, 金井 謙治, 竹内 健, 甲藤 二郎, 津田 俊隆

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 308 ) 35 - 40  2017.11

    CiNii

  • スループット履歴に基づく高信頼且つ省電力映像配信を実現するバッファ制御

    竹中幸子, 金井謙治, 甲藤二郎, 村瀬 勉

    電子情報通信学会ICM研究会   ICM2016-8   1-6  2016.07

    Research paper, summary (national, other academic conference)  

  • Energy-Friendly Mobile Video Streaming using High Throughput Transfer and Buffering Strategy

    Sakiko Takenaka, Ishizu Yuya, Kenji Kanai, Jiro Katto, Murase Tutomu

    IEICE Technical workshop on Communication Quality     CQ2015-141  2016.03

    Research paper, summary (national, other academic conference)  

  • QoS Evaluations of Smart Route Navigation for Efficient Wireless Resource Usage with Multiple Mobile Users

    Kenji Kanai, Sakiko Takenaka, Jiro Katto, Tutomu Murase

    IEICE Technical workshop on Communication Quality     CQ2015-120  2016.03

    Research paper, summary (national, other academic conference)  

  • Energy Consumption Evaluation of ICN Networks

      115 ( 483 ) 213 - 217  2016.03

    CiNii

  • BS-6-16 Performance Analysis of Multimedia Edge Cloud Computing utilizing Transportation Systems(BS-6.Network and service Design, Control and Management)

    Kanai Kenji, Aoki Daiki, Katto Jiro, Tsuda Toshitaka

    Proceedings of the Society Conference of IEICE   2015 ( 2 ) "S - 46"-"S-47"  2015.08

    CiNii

  • BS-6-28 Throughput prediction based on stochastic model of mobile network(BS-6.Network and service Design, Control and Management)

    Wei Bo, Kanai Kenji, Takenaka Sakiko, Katto Jiro

    Proceedings of the Society Conference of IEICE   2015 ( 2 ) "S - 68"-"S-69"  2015.08

    CiNii

  • Performance Evaluation of Proactive Content Caching for Mobile Video through 50-User Field Experiment (画像工学)

    金井 謙治, 武藤 健史, 甲藤 二郎

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   115 ( 171 ) 29 - 34  2015.08

    CiNii

  • Performance Evaluation of Proactive Content Caching for Mobile Video through 50-User Field Experiment (メディア工学 コンシューマエレクトロニクス)

    金井 謙治, 武藤 健史, 甲藤 二郎

    映像情報メディア学会技術報告 = ITE technical report   39 ( 29 ) 29 - 34  2015.08

    CiNii

  • B-7-65 Improvement of Congestion Control of NDNx

    Ishizu Yuya, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2015 ( 2 ) 215 - 215  2015.02

    CiNii

  • B-6-104 Power Consumption Evaluation of ICN toward power-saving video delivery

    Aoki Daiki, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2015 ( 2 ) 104 - 104  2015.02

    CiNii

  • B-6-26 A Proposal on Highly Efficient HCCA utilizing Capture Effect under OBSS Environment

    Kanda Masanori, Kanai Kenji, Katto Jiro, Murase Tutomu

    Proceedings of the IEICE General Conference   2015 ( 2 ) 26 - 26  2015.02

    CiNii

  • B-6-88 Content Offloading Utilizing Transportation Systems and Its Scheduling

    Kurokawa Sayo, Kisara Hiroto, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2015 ( 2 ) 88 - 88  2015.02

    CiNii

  • B-6-126 Evaluations of MPEG-DASH for Multiple Users Using 4K/2K Video

    Harada Rintaro, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2015 ( 2 ) 126 - 126  2015.02

    CiNii

  • B-6-127 Throughput Prediction for Mobile Video Streaming in Mobile Environment

    Konishi Hidenori, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2015 ( 2 ) 127 - 127  2015.02

    CiNii

  • A Study on Comfort Route Navigation with Proactive Content Delivery and an Offloading Scheme for Mobile Devices

    KANAI Kenji, TAKENAKA Sakiko, KATTO Jiro, MURASE Tutomu

    IEICE technical report   114 ( 297 ) 87 - 92  2014.11

     View Summary

    In this paper, we propose a "comfort route" navigation system with proactive content delivery and an offloading scheme for mobile users. To search an optimal path for highly reliable video streaming, we apply a delivery scheduling algorithm, which has been proposed for proactive content delivery scheme, to a path-finding problem. In preliminary evaluation, the result concludes that our approach can drastically reduce transmission time rather than a cellular usage case. This is because the mobile user can communicate with only high-speed hot spots. So, we expect that our approach could also save user's mobile battery life.

    CiNii

  • Evaluations of MPEG-DASH over Mobile Wireless Networks Using 4K Video

    TAKENAKA Sakiko, HARADA Rintaro, KUROKAWA Sayo, MUTO Takeshi, KANAI Kenji, KATTO Jiro

    IEICE technical report   114 ( 297 ) 69 - 74  2014.11

     View Summary

    In this paper, we evaluate Quality of Service characteristics of MPEG-DASH using 4K video over various wireless networks. We also evaluate the effects of various environments, such as the number of users who share the same wireless channel or bandwidth and users' behaviors (e.g. still, walking, and moving on subway), over Long Term Evolution (LTE), 2.4 GHz and 5 GHz Wi-Fi networks. The results conclude that, in case of LTE and 5 GHz Wi-Fi networks, mobile users enjoy high quality 4K video without any video playback interruption in any situations, even on subway. However, in case of 2.4 GHz Wi-Fi networks, mobile users are forced to experience very low quality video with long video playback freeze. This is because network quality of 2.4GHz Wi-Fi network is quite low due to interference waves from other access points of which wireless channels are severely overlapped.

    CiNii

  • An Adaptive Buffer Control Technique Based on Long-term Throughput Prediction for Robust Video Streaming

    KANAI Kenji, KONISHI Hidenori, ISHIZU Yuya, KATTO Jiro

    IEICE technical report. MoNA, Mobile network and applications   114 ( 210 ) 7 - 12  2014.09

     View Summary

    In this paper, we propose an adaptive buffer control technique for robust video streaming. Our approach has two elements which are called "long-term throughput prediction" and "guaranteed playout buffer filling." Since network quality degradation can be detected by using long-term throughput prediction, playout buffer also can be adaptively and proactively controlled. To avoid any video playback interruption due to the network quality degradation, our approach calculates the optimal amount of playout buffer and schedules video download timing in a theoretical manner. We evaluate its performance in real environment and then validate the effectiveness of our proposal.

    CiNii

  • 1-4 Evaluations of MPEG-DASH over Mobile Wireless Networks Using 4K Video

    HARADA Rintaro, KUROKAWA Sayo, TAKENAKA Sakiko, MUTO Takeshi, KANAI Kenji, KATTO Jiro

    Proceedings of the ... ITE annual convention   ( 2014 ) 1 - 4-1"-"1-4-2"  2014.09

     View Summary

    We evaluated various characteristics of 4K video streaming using DASH-JS over LTE, public Wi-Fi services and WiMAX. We did experiments while stopping, walking, and riding the train. We found that a mobile user could enjoy smooth video streaming by using these networks even 4K video.

    CiNii

  • Performance Validation of Proactive Content Caching utilizing Transportation Systems by Field Experiment

    Kenji Kanai, Takeshi Muto, Hiroto Kisara, Jiro Katto, Toshitaka Tsuda, Wataru Kameyama, Yong-Jin Park, Takuro Sato

    IPSJ SIG Notes   2014 ( 30 ) 1 - 6  2014.05

     View Summary

    We propose proactive content caching scheme utilizing transportation systems for robust video streaming with efficient wireless resources usage. In this paper, we develop a prototype system and evaluate its performances by using actual train vehicles and computer simulations. Evaluations conclude that our system can achieve higher-speed and highly-reliable video streaming rather than traditional CDN scenarios using cellular networks.

    CiNii

  • Performance Validation of Proactive Content Caching utilizing Transportation Systems by Field Experiment

    Kenji Kanai, Takeshi Muto, Hiroto Kisara, Jiro Katto, Toshitaka Tsuda, Wataru Kameyama, Yong-Jin Park, Takuro Sato

    IPSJ SIG technical reports   2014 ( 30 ) 1 - 6  2014.05

     View Summary

    We propose proactive content caching scheme utilizing transportation systems for robust video streaming with efficient wireless resources usage. In this paper, we develop a prototype system and evaluate its performances by using actual train vehicles and computer simulations. Evaluations conclude that our system can achieve higher-speed and highly-reliable video streaming rather than traditional CDN scenarios using cellular networks.

    CiNii

  • Performance Analysis and Experimental Validation of Proactive Delivery Scheduling in the Content Delivery System utilizing Transportation Systems

    KANAI Kenji, MUTO Takeshi, KATTO Jiro, TSUDA Toshitaka, KAMEYAMA Wataru

    IEICE technical report   113 ( 472 ) 479 - 484  2014.03

     View Summary

    We have introduced a proactive content delivery system utilizing transportation systems for next generation mobile networks. In this paper, we propose a proactive delivery scheduling, which is called "Smart Scheduler." This scheduler calculates contents quality and quantity and also selects delivery location and timing. To validate and evaluate our method, we experiment in the real environments. Experimental results conduct that our method performs effectively.

    CiNii

  • Analysis and Experimental Validation of Comfort Route Navigation in HetNet

    KANAI Kenji, KATTO Jiro, MURASE Tutomu

    IEICE technical report   113 ( 472 ) 531 - 536  2014.03

     View Summary

    We have already introduced an analytical model for Comfort Route (CR) Navigation providing high communication quality routes to users. In this paper, to estimate CR performance in more realistic environment, we modify the previous analytical model to Heterogeneous Network (HetNet). To validate our model, we employ several scenarios in real experiments. We evaluate throughputs characteristics at ten public Wi-Fi spots in Takadanobaba, which is a city near to our university. We compare the results in real experiments and prove that our model works well with high accuracy.

    CiNii

  • B-6-75 A Study on Improvement of Throughput Prediction Accuracy in Mobile Environment

    Konishi Hidenori, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2014 ( 2 ) 75 - 75  2014.03

    CiNii

  • B-6-94 Proactive Delivery Scheduling in the Content Delivery System utilizing Transportation Systems

    Katto Jiro, Kanai Kenji, Tsuda Toshitaka, Kameyama Wataru

    Proceedings of the IEICE General Conference   2014 ( 2 ) 94 - 94  2014.03

    CiNii

  • B-6-35 Evaluation of Energy Consumption in Video Streaming by Smart-Phones

    Ishizu Yuya, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2014 ( 2 ) 35 - 35  2014.03

    CiNii

  • B-6-39 Performance Evaluation of Proactive Delivery Scheduling and its Multi-channel Extension

    Kanai Kenii, Katto Jiro, Tsuda Tositaka, Kameyama Wataru

    Proceedings of the IEICE General Conference   2014 ( 2 ) 39 - 39  2014.03

    CiNii

  • B-6-125 Power Consumption Evaluation of Video Streaming Application Using a Smartphone

    Aoki Daiki, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2014 ( 2 ) 125 - 125  2014.03

    CiNii

  • Performance Analysis of Comfort Route Navigation with Energy Saving for Mobile Devices

    KANAI Kenji, KATTO Jiro, MURASE Tutomu

    IEICE technical report   113 ( 292 ) 97 - 102  2013.11

     View Summary

    Recently, extending battery life of mobile devices is important for mobile users. We have already introduced Comfort Route (CR) Navigation with energy saving. In this paper, to estimate energy saving effect in a theoretical manner, we employ the analytical model for this route. We find that the effect depends on four basic parameters, such as cellular and Wi-Fi throughput, energy consumption for cellular, Wi-Fi, and idle states, CR and Shortest route cellular usage ratio, and CR longcut ratio. To validate our model, we compare to simulated results and prove that our model works well with high accuracy.

    CiNii

  • Performance Analysis of Comfort Route Navigation Providing High Communication Quality for Mobile Devices

    KANAI Kenji, KATTO Jiro, MURASE Tutomu

    IEICE technical report   113 ( 244 ) 43 - 48  2013.10

     View Summary

    Recently, improving Quality of Service (QoS) in wireless networks is important for mobile users. We have already introduced Comfort Route (CR) Navigation providing high communication quality. In this paper, to estimate CR performance in a theoretical manner, we employ the analytical model for CR. To validate our model, we compare to simulated results and prove that our model works well with high accuracy. We find that the CR gain depends on four basic parameters, such as the cellular and Wi-Fi throughput ratio, the shortest route Wi-Fi coverage area, the CR cellular usage ratio, and user cost which specifies longcut margin. We also find that the best CR gain strongly depends on the cellular and Wi-Fi throughput ratio.

    CiNii

  • BS-7-16 Performance Analysis of Comfort Route Navigation Providing High Communication Quality for Mobile Devices

    Kanai Kenji, Katto Jiro, Murase Tutomu

    Proceedings of the Society Conference of IEICE   2013 ( 2 ) "S - 63"-"S-64"  2013.09

    CiNii

  • BS-7-4 A Simulation Study for Video Streaming over Content-Centric Networking

    Kisara Hiroto, Kanai Kenji, Awiphan Suphakit, Wang Yu, Muto Takeshi, Katto Jiro

    Proceedings of the Society Conference of IEICE   2013 ( 2 ) "S - 39"-"S-40"  2013.09

    CiNii

  • A Study on Visualization of Congestion Levels of Wireless LAN APs

    KANAI Kenji, KATTO Jiro, MURASE Tutomu

    IEICE technical report   112 ( 463 ) 37 - 42  2013.03

     View Summary

    Recently, the demand for visualizing congestion levels of Wi-Fi spots is increasing because Wi-Fi spots are said to be quite congested. In this paper. for this purpose, we employ a simple approximation formula about the relationship between throughputs and the number of active users associated with the access point. In addition, we try to estimate fiiture throughput variation which depends on fluctuation of the associated users using a state transition model. Then, we classify the congestion level into four categories depending on the current and future expected throughputs and evaluate the accuracy of our proposal. We found that our proposal shows acceptable accuracy rate of 70〜90% in our experimental conditions.

    CiNii

  • B-6-142 A Study on Accuracy of lndoor Fingenyrint Localization using WiFi

    KONISHI Hidenori, KANAI Kenji, KATTO Jiro

    Proceedings of the IEICE General Conference   2013 ( 2 ) 142 - 142  2013.03

    CiNii

  • B-6-91 Resource Optimization in the Mobile Terminal using Cloud

    Kanda Masanori, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2013 ( 2 ) 91 - 91  2013.03

    CiNii

  • B-6-144 Performance Comparison ofMPEG-DASH/HTTP Live Streaming over different TCPs in wjreless networks

    Muto Takeshi, Nozaki Tomoya, Kanai Kenji, Katto Jiro

    Proceedings of the IEICE General Conference   2013 ( 2 ) 144 - 144  2013.03

    CiNii

  • B-6-24 A Study on Visualization of Congestion Level of Wireless LAN APs

    Kanai Kenji, Katto Jiro, Murase Tutomu

    Proceedings of the IEICE General Conference   2013 ( 2 ) 24 - 24  2013.03

    CiNii

  • Wi-Fiを用いたIndoor Fingerprint Localizationにおける精度の検討

    小西秀典, 大木哲史, 金井謙治, 甲藤二郎

    情報処理学会シンポジウムシリーズ(CD-ROM)   2013 ( 2 )  2013

    J-GLOBAL

  • Comfort Route Navigation with Energy Saving for Your Mobile Devices

    KANAI Kenji, KATTO Jiro, MURASE Tutomu

    IEICE technical report   112 ( 350 ) 121 - 126  2012.12

     View Summary

    Recently, Internet services and wireless infrastructures have grown widely and diversely, and people can easily access Internet anytime and anywhere. Smartphones have become an indispensable part for this purpose, so people are very nervous about smartphone's battery life. In this paper, we therefore propose Comfort Route for Energy Saving (CRFES) which helps users reach their destinations while stopping by Quality of Service (QoS) fulfilled low-power communication places such as Wi-Fi spots. We evaluate the performance of CRFES in a computer simulation and a real environment. We find that CRFES can save mobile device batteries drastically by using Wi-Fi rather than cellulars with small extra time cost to visit hot spots.

    CiNii

  • BS-4-2 A Proposal and Evaluation of Comfort Route Navigation for Energy Saving

    Kanai Kenji, Katto Jiro, Murase Tutomu

    Proceedings of the Society Conference of IEICE   2012 ( 2 ) "S - 18"-"S-19"  2012.08

    CiNii

  • B-6-22 Evaluation of Longcut Route Navigation based on Actual Throughput Performances of Wireless LANs

    Kanai Kenji, Akamatsu Yuri, Katto Jiro, Murase Tutomu

    Proceedings of the IEICE General Conference   2012 ( 2 ) 22 - 22  2012.03

    CiNii

  • Evaluation of Longcut Route Navigation based on Actual Throughput Performance of Wireless LANs

    KANAI Kenji, AKAMATSU Yuri, KATTO Jiro, MURASE Tutomu

    IEICE technical report   111 ( 468 ) 487 - 492  2012.03

     View Summary

    The demand for access to communication while in transit is increasing, especially among mobile device users. Previous our research has introduced an optimal route problem and a number of solutions to this problem. However, to date, the literature has only presented evaluations based on a theoretical model. In this paper, to validate and enhance the previous work, we observe actual throughput characteristics in public wireless LAN services such as FreeSpot and DOCOMO 's Mzone. We evaluate an optimal longcut route navigation using the results of these observations and show its effectiveness in computer simulations and experiments in actual environment. In both experiments, the optimal longcut route can gain data amount approximately 15 times greater than that of a short cut route.

    CiNii

▼display all

Industrial Property Rights

  • コンテンツ配信システム及び方法

    甲藤 二郎, 佐藤 拓朗, 津田 俊隆, 亀山 渉, 金井 謙治

    Patent

Awards

  • 情報通信マネジメント研究賞

    2017   電子情報通信学会  

  • 山下記念研究賞

    2017   情報処理学会  

  • 英語セッション奨励賞

    2014   電子情報通信学会  

Research Projects

  • 無線LANを用いた車載APの広域被覆配置による広域高速大容量通信

    Project Year :

    2019.04
    -
    2022.03
     

     View Summary

    本研究では、IEEE802.11技術の無線LANを用いた車載APの広域被覆配置による「広帯域かつミッションクリティカルな通信サービス」を実現することを目的とする。第五世代移動通信(5G)では不可能な「高速かつ大量収容」のネットワークを提供するために、次の3つの技術を開発する。(1) AP(アクセスポイント)を提供する車を最適に選択し、移動している車であることを考慮して、APが必要な場所に効率よく配車(通過させる)する技術、(2) APの干渉を抑え、なおかつ複数のAPから通信が良好なAPを時々刻々と選択する技術、(3) 移動する車に対する瞬間的な通信を良好に行う技術

  • High-speed and energy efficient content delivery method using wireless communication quality prediction

    Project Year :

    2017.04
    -
    2020.03
     

  • 世界最高水準のモバイルICT環境を実現する次世代情報通信基盤と応用実証

    Project Year :

    2015.04
    -
    2019.03
     

     View Summary

    本申請の研究開発項目として以下を設定している。基盤技術として、(1) 無線通信履歴の取得、(2) 無線通信履歴を活用した通信品質予測、(3) 品質予測に基づく適応配信制御と最適経路探索。拡張技術として、(4) クラウド拡張、セキュリティ、センサー活用、新無線技術、QoE評価、(5) アプリケーションの具体化とプロトタイプ実装。(1)では、初年度に開発したスマートフォンアプリを使用し、大学周辺の無線通信品質計測を進めている。この時、移動手段や時間情報による場合分けも進めている。(2)では、初年度から継続して隠れマルコフモデルと線形予測分析を併用したスループット予測の検討を進めており、国際学会発表を行うと共に、論文誌投稿を準備している。(3)では、通信品質履歴を活用し、スループットを最大化、もしくは消費電力を最小化する移動経路を提示し、実機実験によって有効性を実証し、国際学会で成果発表を行った。(4)でば、クラウド拡張として、研究室内にパーソナルクラウド、学外に商用クラウドを配し、携帯端末情報をエッジ処理する階層化クラウド環境を整備した。セキュリティに関しては、マルウェア対策のためのトラヒック分析に関する成果発表を行った。センサー活用に関しては、可視光カメラ、赤外線カメラ、測距センサーなどを配した実験環境を構築し、イベント検知に基づく適応配信制御に関する成果発表を行った。無線技術に関しては、5Gを想定した実験環境の情報収集と整備を開始した。QoE評価に関しては、新指標の構築を目指した注視点計測等の成果発表を行った。(5)では、高効率・省電力映像配信アプリケーション、家庭内の8K映像再配信、各種IoTデバイスを用いたセンサーアプリケーション、などのプロトタイプ実装を進めた。これらに加え、次世代ネットワークや無線LANの効率的な制御技術に関する招待講演も行った。本研究課題はおおむね順調に進展している。また、昨年度は研究費の前倒し申請を行い、研究開発の加速に役立てた。(1)では、初年度に開発したスマートフォンアプリを活用し、大学周辺の無線通信品質の計測を進めている。また、アプリ拡張として、ダウンロードに加えてアップロード時の省電力化を図る工夫を加えている。(2)では、現状の隠れマルコフモデルと線形予測分析によるアプローチに加え、機械学習を活用した方式検討の準備を進めている。(3)では、実機実験評価として提案方式の有効性を確認し、論文誌投稿の準備を開始した。(4)では、クラウド拡張では、OpenStackによるパーソナルクラウド構築をほぼ完了し、次年度以降の通信実験、ならびに応用実験の目途を付けた。セキュリティでは、研究成果の論文誌投稿の準備を進めている。センサー活用では、上記クラウド拡張と連携し、エッジコンピューティングも活用した効率的かつ柔軟な応用開発を目指している。無線技術は2020年の5G実用化を想定した実験準備を開始し、シミュレーション評価、実機評価実験の二面から準備を進めている。QoE評価に関しては、観測可能な変数(瞬断時間など)からのQoE推定式も活用した評価実験を進めている。(5)のアプリケーション開発では、各種のプロトタイプ実装と評価に加え、上記クラウド拡張とセンサー活用を統合した今後の新規なプロトタイプ実装の準備を進めている。(1)の通信履歴取得では、スマートフォンアプリの開発・改良を進め、試験的な公開を目指す。ユーザに不要なストレスを与えないインライン計測は昨年度からの継続課題であり、今後も継続する。(2)の通信品質予測では、国際学会の動向も踏まえ、深層学習の導入が緊急の課題であり、新規課題としての検討を進める。このとき、(4)のクラウド拡張を踏まえた深層学習の計算環境整備も課題になる。(3)の適応配信制御と最適経路探索に関しては、プロトタイプ実装も含めた評価として、基礎検討に関しては一通りの目途を付けた。今後は、規模の拡大や無線通信環境の動的な変化への対応など、実用的な課題検討にシフトする。(4)の拡張技術に関しては、まずクラウド拡張とセンサー活用を統合し、各種の通信実験と応用実験への拡張を図る。具体的には、SDN拡張やビッグデータ拡張が可能であり、必要に応じて拡張テーマを設定し、外部資金による新規の研究費申請も検討する。また、(1)の通信履歴取得とセンサー活用の統合も図り、通信履歴取得に加え、人間の行動分析等への拡張を図る。また、新無線技術は5Gへの対応を図り、4K/8K映像配信のシミュレータ・エミュレータ評価を開始し、今後の実機評価に向けた準備を進める。QoEに関しては、人間の知覚特性の計測と反映を継続すると共に、客観指標の活用によるプロトタイプ実装評価への適用を図る。(5)のアプリケーション開発に関しては、最終年度も想定し、各種のプロトタイプ実装を開始する

  • 稠密な無線LANの高品質化を実現するユーザ移動制御方法

    Project Year :

    2015.04
    -
    2018.03
     

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    当初の計画通り,ユーザ(人,車)が所用のためでは無く,通信のために移動する場合における,移動に伴う,通信性能の影響を調査した.[A].インフラモードにおける,移動に伴う通信性能の特性を評価した.ユーザ移動にあたって,スマートフォンにより収集した通信履歴を用いて最適なスループットや消費電力が得られる経路を推定するモデル式を確立した.応用として,映像アプリケーションにおける省電力な映像配信方式の検討を進めた.キャプチャ効果が期待できる無線LAN環境において,双方向フローのスループット向上を目指したMAC制御を検討・評価した.無線LANのQoS向上を目指したMAC制御およびTCP制御のQoE特性評価を実施した.モバイルエッジコンピューティングにおけるサーバ移動が性能に与える影響を評価した.ユーザの過般型無線LAN(テザリング,WiFiルータなど)を移動させることにより,全体の品質向上が図れることを定量的に明らかにした.その応用として,帯域確保型優先制御方法においても,ユーザ移動制御が有効であることを確認した.その応用として,車車間および歩車間通信など,非常に多くのユーザ同士が干渉し合う場合でも,ユーザ移動制御が有効であることを無線LANの場合およびLTE方式の場合において確認した.[B].アドホックモードにおける,移動に伴う通信性能の特性を評価した.アドホックネットワークにおけるユーザ移動(この場合は,ネットワークの移動)制御が品質向上に有効であることを明らかにした.3つ以上の複数のユーザ移動における最適移動地点に関する知見を得た.アドホックネットワークにおけるノード間の最適接続(最適トポロジー)に関して,ユーザが移動することで,最適接続関係を変化させるべきであることを定量的に明らかにした.今年度は,学会などにおける有識者との議論および研究分担者・研究協力者との打ち合わせを頻繁に行い,多くの成果を得た.上述の研究結果を,学会などで発表し,議論を広げることで多くの知見を得ることができた.また,研究自体への外部からの期待も高く,電子情報通信学会情報通信マネジメント研究賞などを受賞したほか,ジャーナルや国際会議にも多く採択された.計画通りに進んでおり,概ね順調と判断している.今年度と同様に,学会などにおける有識者との議論および研究分担者・研究協力者との打ち合わせを頻繁に行い,シナジー効果をねらう.また,同様に研究結果を,学会などで発表し,議論を広げることで多くの知見を得る所存である

 

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Committee Memberships

  • 2017
    -
     

    IEICE 通ソ IoT関連ワークショップ実行委員会  実行委員

  • 2017
    -
     

    電子情報通信学会 MoNA研究会  専門委員

  • 2017
    -
     

    電子情報通信学会 通信方式研究会  幹事補佐

  • 2016
    -
    2017

    電子情報通信学会 CS研究会  専門委員

  • 2016
    -
     

    電子情報通信学会 Dソサエティ 英文論文誌編集委員会  編集委員

  • 2015
    -
     

    情報処理学会 オーディオビジュアル複合情報処理研究会  運営委員

  • 2012
    -
    2014

    IEEE Student Branch at Waseda University  Chair

  • 2012
    -
    2014

    IEEE Student Branch at Waseda University  Chair

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