• Journal of Korea Spatial Information System Society
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• v.6 no.1 s.11
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• pp.73-85
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• 2004

Recently, as the growth of the wireless Internet, PDA and HPC, the focus of research and development related with GIS(Geographic Information System) has been changed to the Real-Time Mobile GIS to service LBS. To offer LBS efficiently, there must be the Real-Time GIS platform that can deal with dynamic status of moving objects and a location index which can deal with the characteristics of location data. Location data can use the same data type(e.g., point) of GIS, but the management of location data is very different. Therefore, in this paper, we studied the Real-Time Mobile GIS using the HBR-tree to manage mass of location data efficiently. The Real-Time Mobile GIS which is developed in this paper consists of the HBR-tree and the Real-Time GIS Platform HBR-tree. we proposed in this paper, is a combined index type of the R-tree and the spatial hash Although location data are updated frequently, update operations are done within the same hash table in the HBR-tree, so it costs less than other tree-based indexes Since the HBR-tree uses the same search mechanism of the R-tree, it is possible to search location data quickly. The Real-Time GIS platform consists of a Real-Time GIS engine that is extended from a main memory database system. a middleware which can transfer spatial, aspatial data to clients and receive location data from clients, and a mobile client which operates on the mobile devices. Especially, this paper described the performance evaluation conducted with practical tests if the HBR-tree and the Real-Time GIS engine respectively.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.11-16
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• 2004

최근 PDA와 같은 모바일 장치와 무선 인터넷의 사용이 확대되고, GPS의 개발로 인하여 위치 기반 서비스가 활발히 연구되고 있다. 그러나, 위치 기반 서비스의 중요한 요소인 이동 객체는 이동에 따른 갱신 비용이 높기 때문에 이전의 디스크 기반의 GIS에서 사용되던 인덱스를 이용하는 것은 효과적 이 지 못하다. 본 논문에서는 위치 기반 서비스를 위한 효과적인 현재 위치 데이타 처리를 위해 공간 해쉬 인덱스와 R-tree 인덱스를 결합한 형태인 HB(Hash Based)R-tree 인덱스를 개발하였다. HBR-tree 인덱스는 위치 기반 서비스에서 이동 객체의 위치 데이타가 빈번하게 갱신된다는 특징을 이용하여 갱신 작업은 HBR-tree 인덱스의 공간 해쉬 테이블 내에서 처리하고, 생성된 공간 해쉬 테이블을 이용하여 R-tree 인덱스를 구성함으로써 빠른 검색 질의 처리가 가능하고 갱신 비용을 줄일 수 있다는 장점이 있다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.11
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• pp.1960-1972
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• 2006

In this thesis, GPS and the electronic mapping were used to realize such a system by recognizing license plate numbers and identifying the location of objects that move at synchronous times with simulated movement in the electronic map. As well, throughout the study, a camera attached to a PDA, one of the mobile devices, automatically recognized and confirmed acquired license plate numbers from the front and back of each cu. Using this mobile technique in a wireless network searches for specific plate numbers and information about the location of the car is transmitted to a remote sewer. The use of such a GPS-based system allows for the measurement of topography and the effective acquisition of a car's location. The information is then transmitted to a central controlling center and stored as text to be reproduced later in the form of diagrams. Getting positional information through GPS and using image-processing with a PDA makes it possible to estimate the correct information of a car's location and to transmit the specific information of the car to a control center simultaneously, so that the center will get information such as type of the cu, possibility of the defects that a car might have, and possibly to offer help with those functions. Such information can establish a mobile system that can recognize and accurately trace the location of cars.