Evaluation System Based On Bp Neural Network Of The City Living Environment Ecological Security

The great progress of science and technology has met the needs of human growing material and cultural, while it has caused many environmental problems at the same time. It is also a serious threat to human health and the sustainable development of human ecological environment, especially, the influence to the ecological security of city which is the important human settlements is the most serious.The ecological security of human settlements of city is one of the problems faced by the society. We estimate the ecological security of human settlements of city scientifically and rationally, which make public profoundly understand the importance of ecological environment, and promote the operability of ecological environment management and construction of the city, and provide good human settlements. What's more, the sustainable development of human ecological security will come true.At present, the ecological security assessment of human settlements of city is still at exploring constantly and developing stage, and there are no ripe theoretical system and appraisal method. Based on the previous studies, the paper uses the theory of ecology and the theory of safety assessment and related methods, and then makes further study to the security assessment of the human settlements of city. In this article, using the PSR model and AHP, bases on all aspects of many factors, a index system of ecological safety evaluation of human settlement of city has been established, firstly, which uses ecological safety of human settlement of city as the target layer; secondly, uses systematic pressure and the state and systematic response as the first rule layer; thirdly, uses resource status and environmental quality, the status of population development, the status of social development, economic response, ecological and social response and so on as the second rule layer; finally, uses 25 basic elements of city environment as the index layer.On the basis of the said research, this paper, taking ecological environment situations of 11 prefecture-level cities in Jiangxi Province for instances, sets the security ratings of ecological environment, and proposes some measures for ecological security management. According to research and application results, it is feasible of the evaluation model of ecological environment security of human settlements of city, which combines BP neural net work with Matlab. The evaluation result is basically in line with circumstances of prefecture-level cities.