Research On The Key Technology Of GIS Based On Simulation Of Forest Fire

Forest is a kind of valuable material resource. It is necessary to have a knowledge of the basic situation around the fire spot in order to discover the fire and put out the fire as soon as possible when forest fire happens, so that we can master it before hand and deal with it in time, and predict and stimulate the spread of the fire. This paper takes Erpi River Forestry Station of Hongxing Forestry Bureau in Yichun as the main research object, conducts in-depth research on key technology related in the GIS system, and puts forward new improved algorithm and its way of application, which promotes further development of GIS system in forest fire. This paper mainly states from the following four aspects:(l)Method Based on multi-features and Support Vector Machine for forest fire recognitionIt adopts new way of color feature extraction, taking the features like the color of the image, texture shape and so on as the eigenvector of the image, and taking Support Vector Machine as the tool of learning. Takes the advantage of existing image data, enhance the accuracy of automatic identification in forest fire. The research result shows that18-color non-uniform quantization algorithm which is based on HSV can be applied to quick recognition of fire ground. Compared with traditional166-color and36-color algorithm, the feature dimension and calculation goes down but the retrieval efficiency goes up by0.6percent. The author have designed a image system of forest fire recognition that include basic functions like feature extraction, integration, tagging, recognition, SVM and data maintenance and have a great effect in application.(2)Simplified algorithm of three-dimensional terrain in forest fireThis thesis is to study the simplified algorithm of three-dimensional terrain, and make a comparative analysis among these simplified algorithms. Besides, this paper improves the simplified algorithm for the mixed-structure quadtree terrain, and builds the multi-resolution texture model and spatial index both based on quadtree structure, which consist a set of data modeling of three-dimensional terrain of the forest fire based on quadtree structure and an efficient deal of texture mapping. It makes the speed of three-dimensional roaming increase by(3)Three dimensional terrain simulation based on GPUCombined with three-dimensional terrain technology, the paper uses ChunkedLOD to achieve the three dimensional terrain simulation which is based on GPU and. Compared with traditional CPU, the method makes full use of the parallel operation ability of GPU, reduces the cost in computing input and improves the rendering efficiency of three-dimensional terrain in forest fire. (4)Forest fire spreading model and improving of algorithmThe paper pays close attention to the factors which may influence fire ground like combustible, topographic slope and meteorological condition. By comparing the features and scope of application of several forest fire spreading model, this paper puts forward a algorithm based on Wang Zhengfei fire spreading model and introduces cellular automata technique into algorithm, taking simulation of forest fire which is based on cellular automata technique into practice.ErPi River Forestry Station of Hongxing Forestry Bureau in Yichun was the research example, and a set of solution of forest fire was proposed by employing dimensional GIS system which was consisted of the forest fire automatic positioning system, terrain simplification model structure, and fire spreading model. This solution would actively promote the development of forestry fire GIS system in our country and have a research and application value.