Study On Emergency Decision Supporting System For Trans-Boundary River Pollutions

Compared with normal river pollution, the pollutions, in the sudden water pollution accidents of trans-boundary river, have the characteristics: photolysis-resistent and biodegradation-resistent, heavy damage, long duration and large ranges. Due to the problems in the practice of risk management and control of trans-boundary river pollution, 362 environmental pollution incidents of past five years have been collected, especially the four incidents have been emphasized on, the water pollution incident in Songhua River in 2005 and in 2010, the two water pollution incident over the boundary of Jiangsu and Shandong in 2009, the domestic and foreign typical watershed cross-border environment pollution case and environmental risk management mechanism are research basis, typical trans-boundary basin (inter-provincial, borders) the songhua river basin are the research object we studied on trans-boundary river pollution emergency decision support system technology.Trans-boundary river pollution was divided into conventional pollution and unconventional sudden pollution. Conventional pollution prediction technology was studied based on data-driven module, applying MATLAB to establish conventional water quality prediction model, Through recent and long-term prediction model analysis of the data available, it conclude that recent average prediction error is 3.82%, long-term average prediction error is 4.74%, which means forecast effect of recent significantly better than that of long-term. In order to predict high concentration pollution plume during emergency with long-time transport and large-scale transmission, the process was modeled by SMS(Surface Water Modeling System) based on mechanism-driven module, meanwhile, constructing two-dimensional random water quality model based on uncertainty principle to research sudden water pollution accidents with data scarce condition, and slick size and concentration of the time line target section was computational predicted and analyzed. By using the related experimental data validate the model parameters set by the means of certainty and uncertainty method separately, obtained that the rate of transverse and longitudinal mass transfer coefficient probability distribution and maximum frequency, Slick length and width of the average error of the analog verification less than 15%, indicating that the model can accurately simulated calculation the polluted plume.To solve the problem of environmental authorities, for the lack of scientific and effective technical assessment on trans-boundary pollution incident emergency plans, Casebase based on CBR/RBR was designed on the basis of analyzing trans-boundary water environmental pollution events happened in domestic and abroad. Using the analytic hierarchy process (AHP) to build case evaluation index system, calculation index weight and proposed including problem description, solutions and results evaluation framework. Comparing and analyzing common mathematical algorithm and the standard model, adopting an improved Euclidean distance method to eliminate index for case matching between the magnitude of differences cause, using decision tree method to establish rule reasoning mechanism to perfect plan formation process. Based on blind number theory, established the credibility assessment algorithm of the plan and the case of nitrobenzene pollution of Songhua river was used for verification.Non-complete information dynamic game process between the local governments was analyzed based on game theory during the pollution happened in in the trans-boundary basin. Identification and definition of the game elements in decision process was made and return matrix of the game was also constructed. Following Nash equilibrium concept for group decision strategy equilibrium, establishing trans-boundary basin pollution group decision model.Based on the scenario-responses emergency management theory and of multi-Agent technology, the collaborative decision-making mechanism in trans- boundary emergency was researched and multitudinous departments in upstream and downstream of river basin was designed as an Agent, modified contract nets protocol (CNP) was chosen as Agent collaboration mechanism, at last, collaborative decision- making of multi-Agent system was established based on the thought of distributed parallel processing design. The conflicts of Agents was solved through the traditional group consistency algorithm processing.Finally, integrating artificial intelligence and software engineering technology, water pollution emergency decision support system and its database and case base was constructed based on WebGIS technology. Case of nitrobenzene pollution happened in Songhua river basin, 2005 was chosen as inversion case to validate river's long-range pollution simulating, rapid preplan generation and decision-making consultation. The function of environmental risk information bulletin and sharing, water pollution emergency response, laws and regulations inquires was realized for the purpose of effective control of the pollution of Songhua river basin and it provides group decision support for trans-boundary pollution.