| By means of the probability and statistics theory, the Grey system theory, the artificial neural network system theory, and the liner programming theory, the oil spill risk analysis of ships and some problems with rather close relationship with it was studied in the thesis.Based on the history records of the ship's oil spill events in china, the probability characteristic of ship's oil spill events was first revealed in chap 2 of the thesis. The oil spill events with different oil spillage levels were studied at different exposure quantity levels respectively. The theoretical base of the study is the Poisson distribution, which is quite suitable for the probability analyses of the events belong to "rare events". By the introduction of the Gamma density into the analysis, we have got the relationship between the probability of the spill events that we are concerned and the oil quantity as the "exposure variable" in the thesis.The conclusion show that the probability characteristic of the oil spill event is not always accordance to the conclusion made by the qualitative analysis only .The difference between them are explored here in a quite detail manner. The result is quite helpful to master the probability characteristics of ship's oil spill events.The ship's oil spillage trend has been forecasted by using the method of the Grey Topology Analysis based on the historic records of oil spill events in our country during 1973-1996. A group of GM (1,1) Models are built for each of the ten different oil spill levels, which are used as "threshold value" in this analysis. The result has shown that the trend after 1996 is still serious. So it is important to pay more attention to prevent the spill occurring especially for the spill events with spilled quantity over 50 tones. This oil spillage trend study was proceed in chap. 3.The model is rather helpful for the risk management of oil spill from ships.As an important part of the oil spill risk research, we precede the factor analysisof ship's oil spill events in chap 4. The ship's oil spill events history records of China and Japan are studied. Three sub-system are involved in the study, they are ship selves' properties, environmental factors and man-made factors. By incorporating the AHP and the Grey system theory in this study, a multi level Grey system model are constructed for the oil spill potential analysis of ships such as oil tankers, cargo ship, etc. The problem of which the comparison or identification of ships with highest or higher oil spill potential among ships that are concerned can be solved with some certain satisfaction. And this is quite useful for the improvement for the ships oil spill monitoring and controlling.In addition to the oil spill potential analysis for ships, we also try to make a comparison of the dangerous level of ship's oil spill events occurrence in different subareas of a sea that are interested. The ANN is first introduced into this kind of analysis, and the model we constructed is rather practicable and reliable. It can make a real time auxiliary for the ships monitoring with the main aim of oil spill event preventing. The study is in chap 5 of the thesis.In chap 6, an ANN system of forecasting the oil spill damage level of a ship's oil spill event is constructed .The system involved 4 sub-systems, they are spill location analysis system, oil analysis system, accidental ship status analysis system and oil spill response analysis system. The shortcoming of which neglect the decreasing function for the oil spill damage by the oil spill response activity existed in studies before are improved. The prerequisite of applying the ANN into the oil spill damage forecasting is that all indexes in the system have a reasonable quantification method or rule. In this part, the quantification rules for each index are proposed. By the benefit of ANN system's excellent characteristics, the model is easy to use at real time works, and easy to be expending in the future.The optimizations for the oil spill response decision...
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