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Policy and decision making in the context of sustainable development requires rapid, effective and efficient access to and integration of appropriate current information from a wide range of sources and disciplines, including land cover dynamic information derived from remotely sensed data. The analysis of data from high spatial resolution satellite sensors has potential in land cover monitoring. In this paper, a post-classification method is used to detect land cover change from multi-temporal satellite data, and particular attention is given to the selection of an appropriate method for land cover classification. The use of a Geographic Information System (GIS) allows further spatial analysis of the data derived from remotely sensed images and analysis of the impact of land cover change on regional sustainable development. The satellite-derived data used in this study are Thematic Mapper (TM) data acquired by Landsat-5 on 14 May 1985, 20 May 1987, 26 April 1990 and 20 May 1993 in Ansan City, Korea. The ...

In this paper, a method on land cover identifying by combining unsupervised algorithm and training data (CUT) was developed. The procedures of land cover classification by using the CUT method are: (a) to carry out remotely sensed image classification by using an unsupervised algorithm (e.g. ISODATA unsupervised classification) to make a land cover classification map, MAP1, with n classes, where n is much greater than the proposed number of land cover classes, m, in the study area; (b) to collect training data for each of the proposed m classes; (c) to make a mask by using training data sets and statistically compute MAP1; (d) to assign the class h in MAP1 to class c in the final classification map, MAP2, if and only if the number of pixels in class c is with the maximum ratio at the statistic. The CUT method was also used to produce a land cover classification map in a test area, Ansan City of Korea, with Thematic Mapper (TM) data acquired by Landsat‐5. The accuracy analysis on the classificatio...

Wireless Local Area Network (WLAN) is a new information access platform which can be used to achieve positioning, monitoring and tracking in wide area. Self-positioned of the network node is the basis and prerequisite for most applications, although the current popular WiFi positioning technology is a position solution for WLAN series standard (IEEE802.11). In this paper, based on the principle of satellite navigation and positioning with wireless sensor networks, the new method of combining GPS and WiFi networks is put forward to achieve seamless positioning and navigation. And the potential problems of existed technology are conducted in-depth discussion by summing up the seamlessly, current location and navigation technology, as well as analyzing existed problems and trends. Finally, the WiFi network assisted GPS positioning algorithm is analyzed in detail.

Using the broadcast ephemeris and precise ephemeris provided by the international GPS service for geodynamics (IGS), the precision of the orbit computed by GPS broadcast ephemeris are analyzed. The orbit precision of broadcast ephemeris is about 5 meters. This paper describes the approach of point positioning using pseudo-range in detail, and then discusses some problems in data processing. Based on this, the differences of positioning accuracy between broadcast ephemeris and IGS precise ephemeris are analyzed and compared. The experiment data is set from IGS tracking stations. With the result calculated, some conclusions are given in the end. In addition, some beneficial conclusions on improving positioning precision are gained.

Technological principle of EDSS and its architecture are introduced in this paper. In proposed EDSS, the four technologies, i.e. GPS, GIS, RS and ES are integrated to provide decision support for environment problem. The system model based on spatial information technology is elaborated on. The integration hierarchical structure of EDSS is also proposed and the conclusion is given in the final

The basic components of location based service (LBS) is introduced in this paper. It is composed of client, network and server. According to the work flow of LBS system, LBS service hierarchical architecture is elaborated on based spatial information Integration. Five levels architecture is described in detail and around 10 primary functions are analyzed also. Finally the application mode of LBS is proposed.

The hybrid genetic algorithm (HGA) were expatriated on, which is integrated by genetic algorithm (GA) and tabu search (TS). The intelligent scheduling was studied by using intelligent characteristic of hybrid optimizing algorithm. Description of scheduling of public traffic vehicles (PTV) was given and simulation results were analyzed. It is demonstrated that intelligent scheduling of PTV based on HGA can overcome the shortcomings of traditional PTV scheduling effectively.

By introducing spatial information technology (SIT), including remote sensing, geographic information system (GIS), satellite navigation system, etc., the principals and methodologies of traffic information collection and management based on SIT were discussed in this paper. The analysis and fusion of all the available information by the support of GIS was described, and the Traffic Information Management System (TIMS) was designed and developed, which has many features such as friendly interface, easy operation and versatile functions. The system can be widely applied to traffic control, vehicle guidance and dispatching, route planning and infrastructure construction.