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Congestion has been a major challenge to urban traffic system. Based on GPS floating-car data (FCD), a method to acquire traffic congestion information is studied. And then, using about 6,000,000 pieces of data generated by 500 taxis in one day as experiment data, we extract the traffic congestion information of a big city in China through GPS data preprocessing, map matching, travel speed estimation, and several other key steps, and finally a map which exhibit the traffic congestion distribution of the city is produced.

Mobile phone location data has the characteristics such as sampling is random, time interval is long and uncertain, there is greater limitations using the traditional K-th optimal path searching algorithm to search path. We propose an improved random probability K-th optimal path searching algorithm (K-OPSA). This method takes several user's mobile location data as the research object, the searching area is limited by using the modified A * algorithm, combined with random probability statistics to obtain the history probability of the road links, integrated K-th optimal path and improved Dijkstra optimal path algorithm to select the optimal road links which covered by the searching area, find out several optimal paths as reference between OD cells. And then describes the design idea, organizational structure and operational process in detail. Analyze the time and space complexity of the algorithm through practical verification, this method can improve the search space and time cost effectively, so as to solve the problem that there are several random paths and the accuracy of the map matching in traditional road network.

In china, with the development of GPS, GIS, RS, 3S technology is gradually used in the agriculture in recent years. This paper introduced the concepts of GPS, GIS, RS. Considering the fact of the Chinese agriculture, we developed the farmland information support system based on the integration of GPS, GIS, RS. With the application of this system in some counties of Yunnan province, the work mode of the department of the agriculture has started to be changed.

Based on SRTM DEM data, Arc Hydro Tools of ArcGIS is firstly employed with Red River as an example in this paper. On the basis of D8 algorithm, the authors then confirm flow direction of raster units according to the steepest gradient as well as starting-point and end-point of river section by means of threshold catchments area. Next, searching for upstream water-supply district of each river section from sub-watershed exit, the boundaries of whole watershed and each sub-watershed are obtained, which will finish characteristics extracting and generate digital Red River watershed. Eventually, experiment result of watershed is analyzed.

Skyline is perfect network three-dimensional visualization software, especially in the mass data transfer and three-dimensional performance. However, Skyline has limitations in spatial analysis. ArcGIS is also excellent GIS software, especially in the data processing and spatial analysis. This paper integrates Skyline and ArcGIS and makes full use of the advantages to construct Web three-dimensional system which can implement spatial analyses, store mass data and release path analysis. This system provides three-dimensional GIS based on Web a new solution.

Considering the hidden danger in the finished stopes in underground metal mines in China, a new cavity data acquisition method based on 3D laser scanning technology is proposed in Dahongshan mine district. This technology uses contactless measurement mode, by which not only the geometric parameter of cavity such as length, area, volume, deformation of roof and wall rock can be gained accurately, but also the security and efficiency of cavity data acquisition are greatly raised. It provides relatively reliable datum for the safety evaluation and the control of emptied stopes as well as the design of ore column stopping. There is certain particularity in application method of 3D laser scanning technology for the finished stopes in mine. For the sake of enhancing the precision and reliability of obtained datum, in this paper, based on systematic analysis of measurement errors of CMS, the key systematic errors of side rolling, pitching and orientation were discussed in detail, and the corresponding calibration method was put forward.

With the development of the project of Formula Fertilization by Soil Testing in china,in order to investigate the soil condition,fertility level,nutrients status,soil degeneration status and the farmland integrated productivity of china,the government decided to start up the project of the Evaluation of the farmland productivity with the field investigation data and the analysis assay data, which were got in the project of Formula Fertilization by Soil Testing. Based on the spatial analysis function of the geographic information system(GIS), such as overlay analysis and spatial interpolation,using soil image,Present land use map and administrative map of the poroject area?this research decided evaluation unit and connected the field investigation data and the analysis assay data. Considering the actual conditions of the poroject area, the experts selected Sixteen affected factors from four aspects as land management?land growing situation?profile situation and soil nutrient content?and the evaluation system of farmland fertility of was built up?Aimed at the affected factors,It adopts the Delphi method to identify the membership function of severa1 affected factors and introduces Analytica1 Hierarch process (AHP) to calculate the weight of evaluating factors.On the basis of these datas,this research used the Additive Model to calculate the Integrated Fertility Index(IFI) and also analyses its space distribution?Because The results are in 1ine with the local situation of the city,This result can be applied to agricultural production.

Parallel editing of spatial data is one of the concern focuses in GIS research. The paper firstly discusses current status of research and analyzes mechanism and implement method of ArcSDE version management. With ArcObjects component as exploitation platform and Visual Basic as tools, a version management component is designed and developed and integrated into application software which implements multi-users parallel editing and version management of spatial data.