• Spatial Information Research
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• v.20 no.3
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• pp.95-106
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• 2012

Recently, with increase and development of the wireless access network area, u-GIS Service is supported in various fields. Especially, spatio-temporal data is used in the mobile environment for the u-GIS service. However, there is no standard for the spatio-temporal data used in different spaces, spatio-temporal data processing technology is necessary to makes interoperability among mobile u-GIS services. Furthermore, it is also necessary to develop the system of gathering, storing, and managing the spatio-temporal data in consideration of small capacity and low performance of mobile devices. Therefore, in this paper, we designed and implemented a spatio-temporal query processing system based on GML to manage spatio-temporal data efficiently in the mobile environment. The spatio-temporal query processing system based on GML can offer a structured storage method which maps a GML schema to a storage table and a binary XML storage method which uses the Fast Infoset technique, so as to support interoperability that is an important feature of GML and increase storage efficiency. we can also provide spatio-temporal operators for rapid query processing of spatio-temporal data of GML documents. In addition, we proved that this system can be utilized for the u-GIS service to implement a virtual scenario.

• 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.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.6
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• pp.1111-1116
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• 2009

For expression of contour lines in mobile GIS environments, the client needs to receive the numerical data with the topographical map from a server. At this point, a client can't get the entire raw data because of the mobile characteristics. The approach to get representative points and to make isogram by interpolation methods, has some problems. The approach requires huge computing overhead at the client and doesn't guarantee the correctness of the isogram. In this paper, a data structure, algorithm and implementation results for efficient transmission of contour information to a client which is constructed from elevation information at a server, are proposed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.151-154
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• 2008

For expression of isogram in mobile GIS environments, the client needs to receive the value data with the topographical map from a server. At this point, a client can't get the entire raw data because of the mobile characteristics. The approach to get representative points and to make isogram by interpolation methods, has some problems. The approach requires huge computing overhead at the client and doesn't guarantee the correctness of the isogram. In this paper, a data structure, algorithm and implementation results for efficient transmission of contour information to a client which is constructed from a elevation information at a server, are proposed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.08a
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• pp.79-82
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• 2008

For expression of isogram in mobile GIS environments, the client needs to receive the value data with the topographical map from a server. At this point, a client can't get the entire raw data because of the mobile characteristics. The approach to get representative points and to make isogram by interpolation methods, has some problems. The approach requires huge computing overhead at the client and doesn't guarantee the correctness of the isogram. In this paper, a data structure and algorithm for efficient transmission of contour information to a client which is constructed from a elevation information at a server, arc proposed. A proposed methods are focused at minimizing the transmission data volume and time.

• Spatial Information Research
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• v.13 no.3 s.34
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• pp.221-237
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• 2005

This study attempts at building a GIS computing environment that incorporates object-relational spatio-temporal database for the time geography model with space-time path, space-time prism and space-time accessibility. The proposed computing environment is composed of ( i ) mobile GIS application for collecting spatio-temporal trajectory data of an individual, ( ii ) spatio-temporal database server that includes time geography model, and (iii) geovisualization client that performs time geographic queries to the spatio-temporal database. The spatio-temporal trajectory data collected by GPS-PDA client is automatically processed and sent to server through data management middleware. The spatio-temporal database implemented by extending a generic DBMS provides spatio-temporal objects, functions, and SQL. The geovisualization client illustrates 3D visual results of the queries about space-time path, space-time prism, and space-time accessibility. This study confirms the possibility of integrating mobile GIS and DBMS for time geography model, and it presents the appropriate database model with spatio-temporal objects and functions that may handle very large data for time geography application.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.1
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• pp.109-113
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• 2011

Recently, according to the development of ubiquitous computing, the u-GIS which not only used in u-Transport, u-Care, u-Fun, u-Green, u-Business, u-Government, and u-City but also used to provides various spatial information such as the location of user is being the core technology of the ubiquitous computing environment. In this paper, we implemented an mobile spatio-temporal Query Processing Systems for handling the Spatio-Temporal Data in mobile equipment.The mobile spatio-temporal Query Processing Systems provides the spatio-temporal data type and the spatio-temporal operator that is expanded by the spatial data type and the spatial operator from OepenGIS "Simple Feature Specification for SQL". It supports arithmetic coding compression techniques that is considered with a spatio-temporal data specific character. It also provides the function of data cashing for improving the importation and exportation of the spatio-temporal data between a embedded spatio-temporal DBMS and u-GIS server.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.1469-1472
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• 2005

웹상에서 제공되던 지리정보서비스가 최근 모바일 GIS 기술의 발달로 인해 이동 단말기에서 서비스가 가능해졌다. 하지만 이동 단말의 가장 큰 목적 중 하나인 휴대성에 초점이 맞추어지다보니 데이터처리의 용량 부족과 통신 속도의 문제에 부딪히게 된다. 또한 현재 모바일 GIS에 지리정보 표현에 따른 표준이 없기 때문에 특정 포맷에 의존도가 높아서 유연성이 떨어진다. 본 연구에서는 국립지리원에서 제공하고 있는 DXF파일 포맷을 추출 및 인덱스화를 통해 경량화를 시키고, OGC(Open GIS Consortium)가 제안한 XML(eXtensible Markup Language) 기반의 표준 공간 데이터 포맷인 GML(Geographic Markup Language)로 변환기능을 수행하는 GML 생성기를 설계, 구현함으로써 추후 확장 및 호환이 용이하도록 설계하였고 이를 WIPI 에뮬레이터에 가시화한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11c
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• pp.1907-1910
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• 2002

최근 들어 활발히 보급되고 있는 이동 통신은 편리하고 신속한 서비스로 폭발적인 가입자 수의 증가를 보이고 있다. 서비스 면에서도 기존의 음성 및 저속 데이터 서비스에서 다양한 종류의 데이터, 즉 멀티미디어 데이터 서비스로 성장한 것이다. 본 논문에서 개발한 모바일 GIS 엔진은 사용자 위치를 기반으로 한 응용인 서비스 예약 등의 부가 서비스, 위치 기반의 광고 서비스, 위치를 기반으로 한 상거래에 활용하기 위해서 개발되었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10a
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• pp.85-88
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• 2001

최근 모바일 환경을 기반으로 서버와 단절 상태에 있는 모바일 장치들과 수시로 변경되는 서버간의 데이타 동기화(Data Synchronization) 문제가 크게 부각되고 있다. 기존 객체 단위의 동기화 기법은 모바일 지리정보시스템(GIS : Geographic Information System)의 영역 단위 데이타 동기화에 적용하기에 적합하지 않다. 이 논문에서는 모바일 클라이언트와 서버간에 무선통신 기반으로 양방향 공간 데이터의 실시간 동기화 프로토콜을 제시한다. 또한 무선통신의 좁은 대역폭과 고비용을 고려하여 서버와 모바일 클라이언트간의 효율적인 양방향 동기화를 위한 로깅 기법을 도입하여, 모바일 클라이언트에 분산된 지역 공간 데이타를 실시간으로 서버와 동기화시키는 기법을 제시한다.