Major Research Subjects of Shiraishi, Y.

Major Research Subject of Shiraishi, Y. (2004-) Assistant Professor

Further information is available at
http://www.csis.u-tokyo.ac.jp/~siraisi/index_en.html

A Framework of Sensor Data Mapping for A Personal Spatial Information System
A various kinds of sensor data from distributed databases on the Internet are useful for personal spatial information systems. We have proposed a framework of sensor data mapping for a personal spatial information system and reports the implementation of the prototype system. Our method generates a query based on user's track log for realizing direct and effective sensor data mapping. This method produces useful information from collected sensor data based on GIS methods such as spatial interpolation and overlay processing. Experimental results suggested that our framework is effective for sensor data mapping in a personal spatial information system.

Incremental Spatial Aggregation for Interactive Browsing and Mapping of Distributed Sensor Data
We have proposed an incremental spatial aggregation method for interactive browsing of distributed sensor data. When an application collects and aggregates a large amount of sensor data over the Internet, the processing time for data search, data transmission and data integration may increase. The response until the aggregated results are presented will be very slow. The increase of a user's waiting time will become a problem when realizing interactive sensor data browsing.Therefore, our method incrementally aggregates sensor data provided from sensor data servers based on location information. A sensor data server is a wrapper that manages time-series sensor data from each sensor network. This method decomposes a query from a browsing client into sub-queries based on the query region. Each data server transmits incrementally the retrieval result for each decomposed region. A mediator agent controls the query execution and the transmission of these results. The browsing client incrementally aggregates these retrieval results and shows the aggregated results at each decomposed region.