Yasuo Tan

Bio: Yasuo Tan is an academic researcher from Japan Advanced Institute of Science and Technology. The author has contributed to research in topics: Emulation & Smart grid. The author has an hindex of 17, co-authored 192 publications receiving 1156 citations. Previous affiliations of Yasuo Tan include Chulalongkorn University & Nagaoka University of Technology.

Secure Data Aggregation in Wireless Sensor Networks: A Survey

Abstract: Data aggregation is a widely used technique in wireless sensor networks. The security issues, data confidentiality and integrity, in data aggregation become vital when the sensor network is deployed in a hostile environment. There has been many related work proposed to address these security issues. In this paper we survey these work and classify them into two cases: hop-by-hop encrypted data aggregation and end-to-end encrypted data aggregation. We also propose two general frameworks for the two cases respectively. The framework for end-to-end encrypted data aggregation has higher computation cost on the sensor nodes, but achieves stronger security, in comparison with the framework for hop-by-hop encrypted data aggregation.

Activity Recognition Using Context-Aware Infrastructure Ontology in Smart Home Domain

Abstract: Nowadays, activity recognition has been proposed in several researches. It is attractive to improve the ability of the activity recognition system because existing research on activity recognition systems still have an error in an ambiguous cases. In this paper, we introduce the novel technique to improve the activity recognition system in smart home domain. We propose the three contributions in this research. Firstly, we design the context-aware infrastructure ontology for modelling the user's context in the smart home. The innovative data, human posture, is added into the user's context for reducing the ambiguous cases. Secondly, we propose the concepts to distinguish the activities by object-based and location-based concepts. We also present the description logic (DL) rules for making the human activity decision based on our proposed concepts. Lastly, We conduct the Ontology Based Activity Recognition (OBAR) system for two purposes: to recognize the human activity, and to search the semantic information in the system, called semantic ontology search (SOS) system. The results show the system can recognize the human activity correctly and also reduce the ambiguous case.

A Novel Human Activity Recognition and Prediction in Smart Home Based on Interaction.

Abstract: Smart Homes are generally considered the final solution for living problem, especially for the health care of the elderly and disabled, power saving, etc. Human activity recognition in smart homes is the key to achieving home automation, which enables the smart services to automatically run according to the human mind. Recent research has made a lot of progress in this field; however, most of them can only recognize default activities, which is probably not needed by smart homes services. In addition, low scalability makes such research infeasible to be used outside the laboratory. In this study, we unwrap this issue and propose a novel framework to not only recognize human activity but also predict it. The framework contains three stages: recognition after the activity, recognition in progress, and activity prediction in advance. Furthermore, using passive RFID tags, the hardware cost of our framework is sufficiently low to popularize the framework. In addition, the experimental result demonstrates that our framework can realize good performance in both activity recognition and prediction with high scalability.

Efficient protocols for privacy preserving matching against distributed datasets

Abstract: When datasets are distributed on different sources, finding out matched data while preserving the privacy of the datasets is a widely required task. In this paper, we address two matching problems against the private datasets on N (N≥2) parties. The first one is the Privacy Preserving Set Intersection (PPSI) problem, in which each party wants to learn the intersection of the N private datasets. The second one is the Privacy Preserving Set Matching (PPSM) problem, in which each party wants to learn whether its elements can be matched in any private set of the other parties. For the two problems we propose efficient protocols based on a threshold cryptosystem which is additive homomorphic. In a comparison with the related work in [18], the computation and communication costs of our PPSI protocol decrease by 81% and 17% respectively, and the computation and communication costs of our PPSM protocol decrease by 80% and 50% respectively. In practical utilities both of our protocols save computation time and communication bandwidth.

Efficient protocols for privacy preserving matching against distributed datasets

Abstract: When datasets are distributed on different sources, finding out matched data while preserving the privacy of the datasets is a widely required task. In this paper, we address two matching problems against the private datasets on N (N > 2) parties. The first one is the Privacy Preserving Set Intersection (PPSI) problem, in which each party wants to learn the intersection of the N private datasets. The second one is the Privacy Preserving Set Matching (PPSM) problem, in which each party wants to learn whether its elements can be matched in any private set of the other parties. For the two problems we propose efficient protocols based on a threshold cryptosystem which is additive homomorphic. In a comparison with the related work in [18], the computation and communication costs of our PPSI protocol decrease by 81% and 17% respectively, and the computation and communication costs of our PPSM protocol decrease by 80% and 50% respectively. In practical utilities both of our protocols save computation time and communication bandwidth.

Machine learning

Abstract: Machine Learning is the study of methods for programming computers to learn. Computers are applied to a wide range of tasks, and for most of these it is relatively easy for programmers to design and implement the necessary software. However, there are many tasks for which this is difficult or impossible. These can be divided into four general categories. First, there are problems for which there exist no human experts. For example, in modern automated manufacturing facilities, there is a need to predict machine failures before they occur by analyzing sensor readings. Because the machines are new, there are no human experts who can be interviewed by a programmer to provide the knowledge necessary to build a computer system. A machine learning system can study recorded data and subsequent machine failures and learn prediction rules. Second, there are problems where human experts exist, but where they are unable to explain their expertise. This is the case in many perceptual tasks, such as speech recognition, hand-writing recognition, and natural language understanding. Virtually all humans exhibit expert-level abilities on these tasks, but none of them can describe the detailed steps that they follow as they perform them. Fortunately, humans can provide machines with examples of the inputs and correct outputs for these tasks, so machine learning algorithms can learn to map the inputs to the outputs. Third, there are problems where phenomena are changing rapidly. In finance, for example, people would like to predict the future behavior of the stock market, of consumer purchases, or of exchange rates. These behaviors change frequently, so that even if a programmer could construct a good predictive computer program, it would need to be rewritten frequently. A learning program can relieve the programmer of this burden by constantly modifying and tuning a set of learned prediction rules. Fourth, there are applications that need to be customized for each computer user separately. Consider, for example, a program to filter unwanted electronic mail messages. Different users will need different filters. It is unreasonable to expect each user to program his or her own rules, and it is infeasible to provide every user with a software engineer to keep the rules up-to-date. A machine learning system can learn which mail messages the user rejects and maintain the filtering rules automatically. Machine learning addresses many of the same research questions as the fields of statistics, data mining, and psychology, but with differences of emphasis. Statistics focuses on understanding the phenomena that have generated the data, often with the goal of testing different hypotheses about those phenomena. Data mining seeks to find patterns in the data that are understandable by people. Psychological studies of human learning aspire to understand the mechanisms underlying the various learning behaviors exhibited by people (concept learning, skill acquisition, strategy change, etc.).

Multiple Imputation for Nonresponse in Surveys

Abstract: 25. Multiple Imputation for Nonresponse in Surveys. By D. B. Rubin. ISBN 0 471 08705 X. Wiley, Chichester, 1987. 258 pp. £30.25.