| 山本 景 | 1551114: M, 2回目発表 | 大規模システム管理 | 笠原 正治,飯田 元,笹部 昌弘,川原 純 |
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title: Improving the performance of Hadoop distributed file system based on the access frequencies of files
abstract: Apache Hadoop has been widely used as a distributed processing platform, and it is desired that the processing speed is improved. In Hadoop, Hadoop distributed file system (HDFS) stores and controls data onto multiple nodes. Previous research shows that the topological relation between a node that processes a task and one on which the data required by the task is located affects the performance of HDFS. In the HDFS default setting, the data is divided into blocks and they are placed on nodes. Two replicas of each block are created and placed onto other distinct nodes. When determining the locations of blocks, the HDFS default strategy does not sufficiently consider the network topology of nodes. In this study, I try to improve the strategy of determining the location of blocks on HDFS. I propose a data placement method such that the data are located near processing nodes in a given network topology and much frequently access blocks are replicated much times and distributed all over the nodes, based on the existing algorithm for contents distribution systems. I develop the Monte Carlo-based simulator, and show preliminary experimental results in order to evaluate the proposed method. language of the presentation: Japanese 発表題目: ファイルのアクセス頻度に着目したHadoop分散ファイルシステムの性能向上 発表概要: Apache Hadoopは分散処理プラットフォームとして広く普及しており，処理速度の高速化が急務である．Hadoopでは，分散ファイルシステムであるHDFSによって複数のノードでデータの保存，管理を行っている．HDFSでは，タスクの実行を行うノードと実行時に必要とされるデータを保持するノードのネットワーク上での位置関係が処理速度に大きな影響を及ぼすことが先行研究で明らかににされている．HDFSのデフォルト設定では，データはブロックに分割され，ノードに配置される．各ブロックに対して，異なるノードに2つの複製が作成される．しかし，複製の生成先を決める際，生成先のネットワーク上での位置関係は十分考慮されていない．そこで，本研究では，HDFSにおけるブロック配置法の改良により，HDFSの処理性能の改善を図る．そこで，コンテンツ配信サーバーの性能向上アルゴリズムを参考とし，必要とされる可能性の高いブロックをなるべく全てのラックに均等に配置する手法を提案する．提案手法を評価するため，モンテカルロシミュレーションを行うシミュレータの作成を行い，予備実験を行った． | |||
| 奥 雅和 | 1551026: M, 2回目発表 | 情報基盤システム学 | 藤川 和利,笠原 正治,飯田 元,新井 イスマイル,猪俣 敦夫 |
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title: An access controling data management system using the combination of secret sharing scheme and attribute-based encryption
abstract: The number of users sharing data with cloud storage is increasing under favor of low cost and accessibility. However, have a problem of confidence such as an outsider leaks data. There are researches improving such problem by using secret sharing scheme. However users' labor of access control for sharing among cloud storages still remains. This paper proposes the system using secret sharing scheme and attribute-based encryption. The system solves the problem of confidence and classifies data which users can access by using secret sharing scheme and attribute-based encryption. language of the presentation: Japanese | |||
| 立花 幸子 | 1551059: M, 2回目発表 | 知能システム制御 | 杉本 謙二,笠原 正治,松原 崇充,南 裕樹 |
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title: Design of prediction governors for systems with input saturation
abstract: This presentation focuses on the tracking control of dynamical systems under the case that actual reference signal can not be available in real time. In such case, although a predicted signal including prediction error is used as a reference signal, the error degrades the control performance of the systems. The previous work presented the predition governor which shapes predicted signals adequately. However, there is a case that amplitude of shaped signals becomes large, and thus the previous result can not be applied to a limited class of systems. In this presentation, we talk about a linear programming based design method of prediction governors for systems with input saturation. Then, the effectiveness of the proposed method is verified by a simulation. language of the presentation: Japanese | |||
| 角間 大輔 | 1551030: M, 2回目発表 | ロボティクス | 小笠原 司,萩田 紀博,高松 淳,丁 明 |
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title:
The Alignment of the Occupancy Grid Maps and the Floor Maps using Graph Matching
abstract: To manage information of positions of mobile robots on one map have many benefits. For example, the robot becomes available on infomation of other robots ,and owners become easy to manage robots. But it is difficult because robots see environments for many ways of expressing styles of environmental maps. In this study, we use floor map, which exist everywhere. The floor maps simply show constructions of the structures, so many robot maps potentially contain information of floor maps. In this paper, we propose the alignment method of the occupancy grid maps and the floor maps using graph matching and take corresponding between maps. The experiment shows the method was able to do coarse alignment of the real-world maps. language of the presentation: Japanese 発表題目: グラフマッチングを用いた占有格子地図とフロアマップの対応付と位置合わせ | |||
| 湯口 彰重 | 1551116: M, 2回目発表 | ロボティクス | 小笠原 司,萩田 紀博,高松 淳,丁 明 |
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title: Eye contact for natural interaction between humans and android robots
abstract: Android robots are used as communication robots due to their human-like appearance and their ability to generate gaze motions. Previous research shows that gaze motions have a more important meaning in a non-verbal communication of android robots, in comparison to other such as facial and body motions. As the android robot lacks of built-in sensors in the eyes, it is necessary to calibrate the robot's gaze for eye contact. In this research, we propose a gaze calibration method for an android robot without built-in sensors based on external sensors such as a motion capture system. language of the presentation: Japanese | |||
| 岡島 知也 | 1551024: M, 2回目発表 | 環境知能学 | 萩田 紀博,小笠原 司,神原 誠之 |
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title: Analysis of the dynamic stress factors in autonomous vehicles and stress reduction by showing information for drivers in autonomous vehicles abstract: In this study, we focus on the dynamic stress which drivers feel on autonomous vehicles, and try to reduce it by showing information of the dynamic stress factors to drivers. Nowadays, autonomous car has become a hot topic beyond the car company or the governments, because of environmental problems and aged society. When the initiative of driving shifts from human drivers to autonomous driving systems, the passengers feel the unique stress to them. We first analyze and sort the dynamic stress factors, and reduce a part of them by showing information. language of the presentation: Japanese | |||
| 中田 彩 | 1551067: M, 2回目発表 | 環境知能学 | 萩田 紀博,小笠原 司,神原 誠之 |
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title: Does being hugged by a robot encourage prosocial behavior and interaction with the robot?
abstract: This presentation presents the effects of being hugged by a robot for both prosocial behaviors and interaction with the robot. In human-human interaction, interpersonal touch including hug is an essential interaction to construct relationship. Also, interpersonal touches showed interesting effects, well known as “Midas touch” which encourage prosocial behaviors. Previous research demonstrated with a robot the effects of user hug on improving impressions, but they did not clarify whether a robot’s hug, especially being hugged by a robot, has enough influences on prosocial behaviors and interactions with the robot. We developed a fluffy robot, which can reciprocate a hug to people and experimentally investigated its effects. In the experiment, a robot requested participants to cooperate to donations with a reciprocated hug or no reciprocated hug. The results of experiment showed significant trend that participants who are being hugged by a robot increased the amount of donations more than participants who are not being hugged by a robot. language of the presentation: Japanese | |||