Faculty Profiles - YOSHIHIRO Takuya

Published Papers - YOSHIHIRO Takuya

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A Competition-based SNS to keep motivation of walking exercise for health promotion

TABE Hiroko, YOSHIHIRO Takuya, INOUE Etsuko, NAKAGAWA Masaru

Joho Chishiki Gakkaishi ( 情報知識学会 ) 21 ( 1 ) 37 - 53 2011.02

Recently in Japan, many computer-assisted systems to motivate people to continue walking exercise have been used for health promotion. Some of them try to motivate people using the mechanisms of SNS; they expect that the comradery and the communications among users in SNS systems motivate users to continue their walking exercise. Those systems, however, have a limitation that only the users who afford to make text-based conversation can use the systems. Thus in this paper, we designed a SNS based system to support continuous walking exercise using the number of daily walking steps instead of text-based conversation. Our system is designed in consideration of three motivation levels with three motivation mechanisms to provide various motivation effects without enforcing users so much labor. Through our experiment it is shown that the computer-assisted systems can provide proper motivation effects to have users continue their walking exercise.

Normalization of biological expression data based on selection of a stable element set

Yoshihiko Bouki, Takuya Yoshihiro, Etsuko Inoue, Masaru Nakagawa

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 6883 ( 3 ) 153 - 166 2011 [Refereed]

Normalization of biological expression data is the process to remove several experimental or technical bias from the data in order to perform accurate analysis. Recently computational analysis of expression data is widely applied since very large number of genes or proteins can be examined simultaneously. In this paper we proposed a new normalization method for expression data which is based on selection of a stable element set. Our idea is that using a part of genes or proteins which is relatively stably expressed leads more accurate normalization. We formulate the problem and give the algorithm to solve it in practical time. Through evaluation with artificial and real data, we found that our method outperforms global scaling, and global scaling tend to over-correct the bias. © 2011 Springer-Verlag.

Adaptive load balancing based on IP fast reroute to avoid congestion hot-spots

Masaki Hara, Takuya Yoshihiro

IEEE International Conference on Communications 2011 [Refereed]

Several load balancing techniques for IP routing scheme have appeared in the literature. However, they require optimization process to compute optimal paths to meet traffic demand so that it requires a mechanism to measure traffic demand and to share them among all routes in order to follow dynamics of traffic. It naturally results in communication overhead and losing sensitivity to follow traffic dynamics. In this paper, we investigate a load balancing mechanism from another approach, i.e., based on IP fast reroute mechanisms. The main idea is simply to forward packets into detour paths supplied by IP fast reroute mechanisms only when packets meet congestion. This strategy enables us to use vacant resources adaptively as soon as they are required to avoid and dissolve the congestion. Through traffic simulation we show that IP fast reroute based load balancing mechanisms improve the capacity of networks. © 2011 IEEE.

Adaptive Load Balancing based on IP Fast Reroute to Avoid Congestion Hot-spots

Masaki Hara, Takuya Yoshihiro

2011 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS (ICC) ( IEEE ) 22 ( 2 ) 97 - 105 2011 [Refereed]

Several load balancing techniques for IP routing scheme have appeared in the literature. However, they require optimization process to compute optimal paths to meet traffic demand so that it requires a mechanism to measure traffic demand and to share them among all routes in order to follow dynamics of traffic. It naturally results in communication overhead and losing sensitivity to follow traffic dynamics. In this paper, we investigate a load balancing mechanism from another approach, i.e., based on IP fast reroute mechanisms. The main idea is simply to forward packets into detour paths supplied by IP fast reroute mechanisms only when packets meet congestion. This strategy enables us to use vacant resources adaptively as soon as they are required to avoid and dissolve the congestion. Through traffic simulation we show that IP fast reroute based load balancing mechanisms improve the capacity of networks.

Predicting combinatorial protein protein interactions from protein expression data based on correlation coefficient

Sho Murakami, Takuya Yoshihiro, Etsuko Inoue, Masaru Nakagawa

Proceedings of the 9th Joint Conference on Knowledge-Based Software Engineering, JCKBSE 2010 35 - 45 2010

In this paper we present a method to predict combinatorial protein protein interactions from protein expression data using statistics over correlation coefficient. Several studies, i.e., bayesian networks or boolean networks, have been presented in the literature to predict protein protein (or gene gene) interactions among more than three proteins (or genes) from expression data. However, they measure the interaction level which includes not only combinatorial effects but also sole effect between two proteins so that it tend to retrieve groups in which every pair of proteins have much effects on each other. Also, they require large data with lots of samples to predict reliable results since they need sufficient number of positive and negative expression values for each target proteins. Our method presented in this paper is practical in that it retrieve only combinatorial effects that appear only when two target proteins get together, and also in that it require less samples than other methods since we use correlation coefficient.

Prediction of combinatorial protein-protein interaction networks from expression data using statistics on conditional probability

Takatoshi Fujiki, Etsuko Inoue, Takuya Yoshihiro, Masaru Nakagawa

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 6278 ( 3 ) 509 - 518 2010 [Refereed]

In this paper we propose a method to retrieve combinatorial protein-protein interaction to predict the interaction networks from protein expression data based on statistics on conditional probability. Our method retrieves the combinations of three proteins A, B and C which include combinatorial effects among them. The combinatorial effect considered in this paper does not include the "sole effect" between two proteins A-C or B-C, so that we can retrieve the combinatorial effect which appears only when proteins A, B and C get together. We evaluate our method with a real protein expression data set and obtain several combinations of three proteins in which protein-protein interactions are prediced. © 2010 Springer-Verlag.

Reducing routing loops under dynamic metrics in wireless mesh networks

Takuya Yoshihiro

GLOBECOM - IEEE Global Telecommunications Conference 2010 [Refereed]

Many dynamic metrics for wireless mesh networks (WMNs) to improve communication quality are proposed so far. However, all of them have possibility to create temporary routing loops which may cause severe congestion and disruption of communications. In order that WMNs are regarded as a reliable infrastructure of the next generation, such routing loops are strongly desired to be eliminated since they bring the possibility of service disruption. In this paper, we propose a mechanism called Loop-free Metric Range (LMR) to make existing dynamic metrics loop-free by restricting the range of metric values to change. LMR is applicable to a major part of existing metrics such as ETX, ETT, MIC, and so on without any message overhead. We show the mechanisms of LMR, theoretical results on the range of loop-free metric values, and simulation results on the effectiveness of LMR. ©2010 IEEE.

A System to Mine Hidden Effects from the Classes for Preventing Lifestyle Related Diseases

YOSHIHIRO Takuya, INOUE Etsuko, TABE Hiroko, NAKAGAWA Masaru

Joho Chishiki Gakkaishi ( 情報知識学会 ) 19 ( 1 ) 2 - 14 2009.03

In this paper, we present a system to support medical doctors to derive hidden effects of the classes that are organized to improve lifestyle related disease. Recently in Japan, the number of such kind of classes is increasing rapidly, but it is not easy to know the type of participants for whom each class has particular effects. Our system does a data mining to find a group for which a class has particular effect by generating several combinations of conditions from the data of the classes. With our system, one can find groups of particular effect without much time and labor, and can also confirm the original data from which the effect is revealed. Our system can be used as a fundamental analysis tool to analyze the data of that kind of classes.

A New Interactive Graph-Based Visualization Method for Large-Scale Clustering Analyses

INOUE Etsuko, YOSHIHIRO Takuya, NAKAGAWA Masaru

The IEICE transactions on information and systems ( 一般社団法人電子情報通信学会 ) 92 ( 3 ) 351 - 360 2009.03

本研究では,大規模なクラスタリング結果のグラフを用いた可視化手法を提案する.一般にグラフによる要素間の関係の可視化は,データが大規模になるとノード数・リンク数ともに増加するため,グラフが過密になり要素間の関係把握が困難になる.提案手法では画面上の表示ノード数・リンク数を一定範囲に保ちながら,全体の概観から詳細な要素間の関係までの表示粒度を連続的に変更することができ,いわばクラスタリング結果空間を自由に探索することができるようなインタラクティブな閲覧環境を実現している.このような閲覧環境の実現にはユーザの操作にリアルタイムに追従できる高速なグラフ変形が必須であるが,本論文ではこれを実現するデータ構造とアルゴリズムを提案する.また, Javaを用いて試作を行い,本手法の評価を行った.

Loop-free Link Stability Metrics for Proactive Routing in Wireless Ad Hoc Networks

Takuya Yoshihiro

2009 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, VOLS 1-8 ( IEEE ) 502 - 506 2009 [Refereed]

To improve communication quality in wireless ad hoc networks, it is definitely important to select stable links as communication paths. To this end, various mobility metrics are presented in the literature. However, the routing loop problem, which is inevitably involved in link-state proactive routing scheme, has not been discussed well. In this paper, we propose a simple dynamic metrics in respect of link stability, which is loop-free throughout dynamic metric transition. Through a theoretical analysis of loop-freeness, we present our new strategy to achieve loop-freeness with sufficiently low cost for ad hoc networks.

Loop-free link stability metrics for proactive routing in wireless ad hoc networks

Takuya Yoshihiro

IEEE International Conference on Communications 2009 [Refereed]

To improve communication quality in wireless ad hoc networks, it is definitely important to select stable links as communication paths. To this end, various mobility metrics are presented in the literature. However, the routing loop problem, which is inevitably involved in link-state proactive routing scheme, has not been discussed well. In this paper, we propose a simple dynamic metrics in respect of link stability, which is loop-free throughout dynamic metric transition. Through a theoretical analysis of loop-freeness, we present our new strategy to achieve loop-freeness with sufficiently low cost for ad hoc networks. ©2009 IEEE.

Developing an integrated database system for the large-scale proteomic analysis of Japanese Black cattle

NAGAI Kouhei, YOSHIHIRO Takuya, INOUE Etsuko, IKEGAMI Haruka, SONO Youhei, KAWAJI Hideya, KOBAYASHI Naohiko, MATSUHASHI Tamako, OHTANI Tsuyoshi, MORIMOTO Koichi, NAKAGAWA Masaru, IRITANI Akira, MATSUMOTO Kazuya

Nihon Chikusan Gakkaiho ( 公益社団法人日本畜産学会 ) 79 ( 4 ) 467 - 481 2008.11

We developed an integrated database system of Japanese Black cattle to accelerate our large-scale proteomics to find bio-markers which control quality of Wagyu beef. This system manages enormous data throughout our process of analysis by collecting data scattered in different analytical machines, software and our own data sheets. The data in our system includes 43 traits on Japanese Black cattle (mainly the items on beef quality and bloodlines), expression data, and identification data of hundreds of proteins. The system also provides us flexible search interfaces to fetch data sets to put into further analyses or data mining processes. In this paper, we present whole description about our system and about the data having been accumulated. Further we evaluate the availability of our system through several analytical operations, (1) comparison of carcass weights between progenies of sire-B and sire-C, (2) analysis of the effect of maternal grand sire on the carcass traits of sire-D's progenies, (3) comparison of expression levels of ten proteins between the low rib-thickness group and the high rib-thickness group, and (4) analysis of the correlation between expression level of F1 ATP synthase chain F and carcass traits.

Mining combinatorial effects on quantitative traits from protein expression data

Takuya Yoshihiro, Etsuko Inoue, Masaru Nakagawa

Frontiers in Artificial Intelligence and Applications ( IOS Press ) 180 ( 1 ) 359 - 367 2008 [Refereed]

In this paper we proposed a data mining method to find interesting relation among the small number of proteins and a quantitative trait from protein expression data. It is practically important to find small number of proteins which in combination effects on some characteristics of samples because it motivates further experiments to investigate the function of the proteins. Further, treating quantitative trait rather than categorical data is also practically important since considerable part of characteristics of samples is represented by quantitative values. Our data mining method apply discriminant analysis into protein expression data and quantitative trait data to derive interesting relations among them. © 2008 The authors and IOS Press. All rights reserved.

A Single Backup-table Rerouting scheme for fast failure protection in OSPF

Takuya Yoshihiro

IEICE Transactions on Communications ( Institute of Electronics, Information and Communication, Engineers, IEICE ) E91-B ( 9 ) 2838 - 2847 2008 [Refereed]

We propose a practical link protection scheme, called Single Backup-table Rerouting, (SBR) as an extension for Open Shortest Path First (OSPF). SBR protects against any single link failure as soon as the failure occurs if the topology of every area in OSPF is two-link-connected. An efficient algorithm to compute a set of backup tables is provided for networks with symmetric link costs. The foremost feature of SBR is that the backup process is fully distributed, so no message exchange is required and the modification of OSPF is minor. OSPF is extended with the following: only one extra backup routing table, a 2-bit flag at each traffic packet, and a process for handling the backup table. There are no changes to the message format of OSPF. In this paper, we present the practical link protection scheme by fitting SBR into several OSPF specific mechanisms such as OSPF areas, Equal Costs Multipath (ECMP), and virtual links with proofs of their correctness. Furthermore, together with a loop-free routing technique for link-state routing, SBR guarantees the consistency of every route against a single link failure, even during the path recomputation phase, until it converges to the new shortest paths. Copyright © 2008 The Institute of Electronics, Information and Communication Engineers.

Designing Database Systems for Efficient Analyses in Breeding Tests of Plants

INOUE Etsuko, YOSHIHIRO Takuya, KAWAJI Hideya, NEGORO Keiichi, HANADA Hiromi, WANAKA Manabu, NAKAGAWA Masaru

Joho Chishiki Gakkaishi ( 情報知識学会 ) 17 ( 1 ) 2 - 14 2007.02

We developed a database system to store and analyze crop data which are obtained in breeding tests of various plants. In operating breeding tests, researchers pay considerable labor not only for cultivating but also analyzing obtained data. To improve it, we performed a data-modeling of crop data through investigating a number of reports and also through having interviews with several researchers of breeding. By managing crop data with this model, our system enables researchers to analyze the crop data efficiently, which results in reducing analysis labor of researchers. Our system is designed in consideration of usability: researchers can easily store crop data with their own spreadsheet files. They can also analyze the stored data through web browsers with simple operations such as selecting conditions and items to compare. Further, they can search data with conditions and the result can be downloaded. We evaluated our system by applying some breeding tests, and then we obtain good evaluation results with the comment that the system is useful and it reduces the labor of analyses.

Healthcare Supporting Systems over the Internet

SATOMURA Hiroaki, TANAKA Takehiko, YOSHIHIRO Takuya, NAKAGAWA Masaru

Joho Chishiki Gakkaishi ( 情報知識学会 ) 16 ( 2 ) 59 - 62 2006.05

We have constructed the healthcare supporting systems for aged people, for patients with diabetes, and for pediatric patients and their families. In these systems, the people in need of nursing care actively and regularly send the healthcare data while the medical personnel view them to make use of subsequent medical services or nursing cares. The architecture is almost common to these systems in the sense that there exists a web and database server together with Internet-enable devices. However, since the data in the databases and to be exchanged were entirely difficult, the systems have been designed, implemented and maintained separately. In this paper, we review the features of the systems, and discuss the united, versatile database system for remote healthcare support.

A Database System for High-Throughput Transposon Display Analyses of Rice

INOUE Etsuko, YOSHIHIRO Takuya, KAWAJI Hideya, HORIBATA Akira, NAKAGAWA Masaru

Joho Chishiki Gakkaishi ( 情報知識学会 ) 16 ( 1 ) 28 - 38 2006.01

We developed a database system to support whole experiments which analyze correlation between genotypes and phenotypes by using transposons. We also evaluated the system by applying to our experiments with transposon <i>mPing</i> in rice. Our research group grow large-scale mutant series of rice by taking advantage of <i>mPings</i>, and study correlation between genotypes and phenotypes for predictions of gene functions. However, the analytical phase, in which we find mutation spots from waveform data, involves several problems from a viewpoint of labor amount, and it becomes one of bottlenecks in large-scale experiments. As a solution, our database system manages all the analytical data throughout the experiments, and provides interfaces to perform overall analyses by detecting mutation spots and analyzing correlation between the spots and traits. In order to evaluate the system, we apply to experiments with <i>mPing</i> in rice, and confirmed that our system works effective to reduce the analytical labor by several times. This system realizes high-throughput transposon display analyses in large scale.

System Support of Diabetic Self-treatments Using Mobile Phones

Takuya Yoshihiro, Kazuhiro Ikemoto, Kumiko Mori, Sachiko Kagawa, Yasuhisa Yamamoto, Masaru Nakagawa

KNOWLEDGE-BASED SOFTWARE ENGINEERING ( I O S PRESS ) 140 263 - 272 2006 [Refereed]

We developed a system which helps diabetic people making self-treatments in their home, by exchanging treatment information and advices with their doctors and nurses in the hospital. To cure diabetes, it is essential to make daily treatment such as improving meals, doing exercises, taking insulin, or taking medicines to keep blood glucose level in a proper range. However, since many of diabetic people do not go to see their doctor frequently, say, about once a month, they tend to be lazy about self-treatments during that long period of time. As a result, many people are suffering from diabetes long time. To improve this situation, we developed the system to help self-treatments. In our system, patients report their concrete treatment activities to their doctors using mobile phones. The doctors watch the reports and make proper encouraging advices to the patients. We expect that Such kind of advices call raise patients' motivation for their self-treatments. In designing the system, we tried to have doctors understand the concrete activities of patients' self-treatments through patients' daily reports, so that doctors can make proper and effective advices and encouragements. In this paper, we introduce the new diabetic self-treatment supporting system and report the evaluation results through a short-term test operation with several patients.

Single backup table schemes for shortest-path routing

Hiro Ito, Kazuo Iwama, Yasuo Okabe, Takuya Yoshihiro

Theoretical Computer Science 333 ( 3 ) 347 - 353 2005.03 [Refereed]

We introduce a new recovery scheme that needs only one extra backup routing table for networks employing shortest-path routing. By precomputing this backup table, the network recovers from any single link failure immediately after the failure occurs. To compute the backup routing table for this scheme, we use an almost linear time algorithm to solve the {r,v}-problem, which is a variation of the best swap problem presented by Nardelli et al. We further show that the same solution can be computed in exactly linear time if the underlying graph is unweighted. © 2004 Elsevier B.V. All rights reserved.

A Remote Home Care System in an Underpopulated Area

Miyamoto Hironobu, Okamoto Yuu, Kowaki Ryohei, Yoshihiro Takuya, Horiuchi Emiko, Nakagawa Masaru

Joho Chishiki Gakkaishi ( 情報知識学会 ) 14 ( 2 ) 57 - 60 2004

We developed a remote aged care system for Hanazono village which is one of the typical underpopulated villages in Japan. In many of such depopulated villages, there is the problem that the number of visiting nurses who provide aged care services is not enough. As a result, visiting nurses can visit aged people not so often (it might be once a week or so), and hence aged people is easy to lose their health. To improve this situation, our system helps visiting nurses get hold of the health condition of aged people by showing the information of their daily health condition which is input everyday by aged people at their own houses. Here, to make a easy input operation even for aged people, we use L-mode terminals at each house and design easy-to-operate Web pages which are accessed by the terminal. We further performed a test operation of our system in Hanazono village and confirmed the effectiveness of our system.

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