• Journal of Internet Computing and Services
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• v.6 no.5
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• pp.97-110
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• 2005

Recently, many WMS(Web Map Services) and POI(Point of Interest) services come to be in service on the Internet using Web GIS(Geographic Information System) as Information Technology and computer H/W are evolved faster in its speed, network bandwidth and features. The Web GIS is, however, limited and constrained on the specification of its system configuration, the service class provided and the presentation methodology of a map. As the mobile Internet becomes popular in mobile service, Web GIS service on mobile environment is strongly required and to be provided by location based WMS(Web Map Service) on a mobile client such as PDA with location information of the user. In this paper, we made an effort to design and implement a GIS computing environment by thin client for mobile web map service. For implementing the thin client GIS computing environment. we were using NGII's(National Geographic Information Institute's) DXF map, representing the map by SVG(Scalable Vector Graphics) recommended by OGC(OpenGis Consortium), and adapting standard XML web service to provide the thin client GIS service on PDA by applying the location information of the user in realtime with GPS on mobile environment.

• The KIPS Transactions:PartD
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• v.10D no.3
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• pp.359-366
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• 2003

Although the reuse of the cached data for scrolling the map reduces the amount of passed data between client and server, it needs the conversions of data coordinates, selective deletion of objects, cache compaction and object structuring step in the clients. The conversion is a time- intensive operation due to limited resources of mobile phones such as low computing power, small memory. Therefore, in order to control the map efficiently in the vector map service based mobile phones, it is necessary to study the methods which reuse cached objects for reducing wireless network bandwidth and overwhelming the limited resources of mobile phones as well. This paper proposes the methods of reusing pre-received spatial objects for map control in the mobile vector map service system based on client-server architecture. The experiments conducted on the Web GIS systems with real data show that the proposed method is appropriate to map services for mobile phone. We also analyze the advantages and drawbacks between the reuse of cached data and transmission of raw data respectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1588-1596
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• 2004

Recently, many WMS(Web Mapping Services) and POI(Point of Interest) service on to be in service on the Internet using Web CIS(Geographic Information System) as information Technology and computer HW are evolved faster in its speed, network bandwidth and features. The Web GIS is, however, limited and constrained on the specification of its system configuration, the service class provided and the presentation methodology of a map. As the mobile Internet becomes popular in mobile service, Web GIS service on mobile environment is strongly required and to be provided by LBS(Location Based Service) on a mobile client such as PDA with location information of the user. In this paper, we made an effort to design and implement a GIS computing environment by thin client for mobile web mapping service. For implementing the thin client GIS computing environment, we were using NGII's(National Geographic Information Institute's) DXF map, representing the map by SVG(Scalable Vector Graphics) recommended by OGC(OpenGis Consortium), and adapting standard XML web service to provide the thin client GIS service on PDA by applying the location information of the user in realtime with GPS on mobile environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1612-1616
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• 2006

For map services in the mobile environment, it should be considered that resource restriction or the mobile device. on, if a map database dedicated to mobile services may not be developed, the spatial data extracted from general map databases should be simplified before transmitting. % is paper suggests the filtering methods to manipulate the spatial data, which are changed to be able to displayed on the mobile devices. The suggested methods are evaluated by experiments. This method is based on the map generalization operator 'selection' and is refined to adapt on mobile phone environments.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1253-1258
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• 2006

In the mobile vector map service environments, there are problems like as terminal resource shortage and transmission delay for the characteristics of large spatial data. For the normal mobile vector map services, some techniques are required to overcome the problems. Spatial data compression approach is one of the techniques to reduce the bandwidth and the waiting time at clients. However it also must be considered that the effect on total efficiency caused by the overhead of compression and restoration time. This thesis proposes two spatial data compression techniques. First approach is to get relative coordinates to first coordinate of each object. The other approach is to compute client coordinates before transmission. Through the implementation and experiments, proposed techniques are evaluated the compression effects and efficiency.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.358-362
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• 2004

According to the rapid advance of computer and communication techniques, the request of mobile internet services is highly increasing. However, the main obstacles for mobile vector map service environments, are large data volume and narrow wireless bandwidth. Among the many possible solutions, spatial data compression technique may contribute to reduce the load of bandwidth and client response time. This thesis proposes two methods for spatial data compression. The one is relative coordinates transformation method, and the other is client coordinates transformation method. And, this thesis also proposes the system architecture for experiments. The two compression methods could be evaluated the compression effect and the response time.

• Journal of KIISE:Computing Practices and Letters
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• v.12 no.1
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• pp.9-20
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• 2006

Web Map Service on mobile environment, provided with cost effective mobile GIS contents and user preferred POIs(Points of interests), is strongly required at this moment when mobile and portable Internet is rapidly spreaded on mobile user community as information technology and mobile HW are evolved in its speed, bandwidth and features. As the mobile and portable Internet becomes popular in mobile services, LBS(Location Based Service) is positioned on a mobile client as one of the best information infra services. Recently mobile GIS (Geographic Information System) comes in service to support LBS, but it is constrained and limited on its system configuration and its presentation methodology of a map, and also it depends on its run time environment. In this paper, we made an effort to design and implement a GIS computing platform with server based thin client for mobile WMS(Web Map Service). For its cost effective Platform which could be easily building up POIs and GIS contents, we're not using commercial GIS solution but NGII's (National Geographic Information Institute's) DXF numerical map, and representing the maps, GIS contents and POIs by SVG(Scalable Vector Graphics) recommended by OGC(OpenGis Consortium). We're also adapting de facto standard of XML web service technology such as WSDL, SOAP to provide real time mobile GIS service on PDA as well as mobile terminal by applying a GPS receiver for a user's location information on mobile environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.3
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• pp.452-458
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• 2002

Although the reuse of the cached data for scrolling the map reduces the amount of passed data between client and server, it needs the conversions of data coordinates, selertive deletion of objects and cache compaction at client. The conversion is time intensive operation due to limited resources of mobile phones such as low computing power, small memory. Therefore, for the efficient map control in the vector map service based mobile phone, it is necessary to study the method for reducing wireless network bandwidth and for overwhelming the limited resources of mobile phone as well. This paper proposes the methods for racking pre-received spatial objects in client-server systems for mobile CIS. We also analyze the strengths and drawbacks between the reuse of cached data and transmission of raw data respectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.4
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• pp.950-954
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• 2004

According to the rapid advance of computer and communication techniques, the request of mobile internet services is highly increasing. However, the main obstacles for mobile vector map service environments, are large data volume and narrow wireless bandwidth. Among the many possible solutions, spatial data compression technique may contribute to reduce the load of bandwidth and client response time. This thesis proposes two methods for spatial data compression. The one is relative coordinates transformation method, and the other is client coordinates transformation method. And, this thesis also proposes the system architecture for experiments. The two compression methods could be evaluated the compression effect and the response time.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.201-204
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• 2002

Although the reuse of the cached data for scrolling the map reduces the amount of passed data between client and server, it needs the conversions of data coordinates, selective deletion of objects and cache compaction at client. The conversion is time intensive operation due to limited resources of mobile phones such as low computing power, small memory. Therefore, for the efficient map control in the vector map service based mobile phone, it is necessary to study the method for reducing wireless network bandwidth and for overwhelming the limited resources of mobile phone as well. This paper proposes the methods for caching pre-received spatial objects in client-server systems for mobile GIS. We also analyze the strengths and drawbacks between the reuse of cached data and transmission of raw data respectively.