With more and more information acquired by radar remote sensing the classification technology for radar imagery is heading towards high precision, high correctness and rapidness due to the application of new algorithms, theories, ancillary information and characteristics. In the paper, the development of new classification technology for radar imagery is overviewed. To improve the precision and stability, the authors consider that new characteristics (polarimetric and interferometric information, multi_temporal and geographic information etc.), new theories (like wavelet, fractal and fuzzy theory etc.), and new designed algorithms (such as improved max_likelihood, context Classifier and neural network classifier etc.) should be applied to the classification process of radar imagery.
The image characteristics of the sand_dust storm processies monitored by meteorological satellite are described, and different synoptic systematic models for the formation of sand_dust storm are analyzed. In addition, a preliminary study is made on the climatic reasons for the repeated occurrence of sand_dust storm in 2001.
Based on the practical demands for coal bed gas exploration in the loess highlands of the Ordos Basin, the authors, by interpreting the remote sensing images in the study area and utilizing the Statistics and Analysis of Fracture Density method, have predicted the high permeation belt of the coal bed gas in the study area, and made a preliminary evaluation on the favorable sectors for coal bed gas exploration. The result has provided important references for the coal bed gas in the oil field.
This paper introducs the spectral character of main vegetations along Yanhe river, which are determined by the contents of many materials within vegetations, such as chlorophyll, carotenoids, nitrogen, lignin and cellulose. The spectra are also affected by many factors, like Leaf Area Index, sun's position, atmosphere condition, background character, observation geometry and growthing period of vegetations.
Based on the interpretation of color-infrared aerial photographs and field investigation, this paper has summarized various image characteristics of rock-soil ground and geological danger areas along Kuisal Highway. This can deliver new reference materials for remote sensing investigation in the exploring of westpart of our country.
Remote sensing was used to investigate types, distributions and areas of the wetland in Shinghai. As a result, the distribution and zoning of vegetable communities in wetland, the micromorphologic units, the habitats of rare birds and the benthons were identified. Using the time characteristic of remote sensing images, the authors also studied ecological capacity of rare birds in the natural reserve, and revised the base maps.
Based on the data from remote sensing investigation on islands and water depth as well as from aero_magnetic survey, basic GIS for the Nansha Islands (NsbGIS) is formed by using computer, GIS, database and webGIS technology. NsbGIS is a professional information system for providing comprehensive and actual data as well as decision_making basis for marine planning, environmental protection, natural resources development, boundary negotiation, regional cooperation and sustainable marine development. This paper focuses on introducing the establishment of database of NsbGIS and the development of its function. In addition, some cases are given in the paper.
Being a database management system, GIS can manage to capture, store, and analyze processes and display spatial data. Therefore, it is a very powerful tool for studying spatial objects. This paper describes the establishment of spatial database system for estimating regional stability of Hubei province by using GIS software Arc/Info and on the basis of available geo_data and remote sensing data, which constitute an important source to capture and updata data in the spatial database system. The content, function, application and significance of establishing the spatial database system are also discussed.