Chongjun Yang

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This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, redistribution , reselling , loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents(More)
Spatial Information Search Engine (SISE), aiming to search the World Wide Web for online geographic information to meet the end users needs, is a totally new research area in the field of spatial information sharing. In this paper we introduce an OpenGIS WMS specification based SISE prototype system. This SISE prototype is capable of discovering available(More)
Web Map Service (WMS) provides spatial information to Internet users by map images. Commonly, spatial data are stored as vector data. It is a long job to create map images from vector data. To reduce the time cost, we employ Linux cluster. When a map is requested, coordinates scope that is a rectangle defined with xmin, ymin, xmax, ymax must be specified.(More)
Internet-based GIS (WebGIS) development on infectious disease is a challenge, especially during its severe outbreak. Global SARS information WebGIS we developed is a typical case application. This work discusses the methods and steps on how to design and develop the WebGIS application. A "thin-server" and Java Applet based WebGIS solution is employed to(More)
Mobile computing system based on personal digital assistant (PDA) products has been used widely, and location-based service (LBS) is one of the most promising application directions of GIS. It is important to integrate the mobile computing technology and GIS technology to meet the need of LBS. The purpose of the paper is to propose a solution of mobile GIS(More)
With the rapid development of GIS, embedded technology and wireless communication technology, embedded GIS based on wireless networks becomes an active research area in the field of GIS. On the one hand, mobile embedded GIS enables users to enjoy spatial information service by wireless networks anytime and anywhere. On the other hand users can customize(More)
The problem of content-based retrieval of remote sensing images presents a major challenge not only because of the surprisingly increasing volume of images acquired from a wide range of sensors but also because of the complexity of images themselves. In this paper, a prototype software system for content-based retrieval of remote sensing images, namely(More)
Traditionally, to provide Web Map Service (WMS), a program named "Map Server" must be run as a standalone process to create map images. Map server receives the requests from the clients, construct SQL statements and send them to spatial database. Spatial database execute the SQL statements and send the results to map server. Map server gets the features,(More)
Data sharing and integration are the inherent request of GIS. Data format conversion, data interoperability and direct data access are three ways of data sharing. All of them have many shortcomings respectively. So this paper proposed a method to build a WebGIS for sharing and integration of multi-source heterogeneous spatial data well. It introduced(More)