The Study Of The Method Of Risk Assessment Of Warship

The risk assessment was applied to the marine engineering in the 1970s'. Hitherto, IMCk IACS and many countries have carried out researches on the risk assessment. In comparison with the researches done by IMO and IACS, the researches on the risk assessment are not enough in China. This thesis concentrates on the study of the methods of risk assessment, in which the formal safety assessment (FSA) is applied to the risk assessment of warship and data envelopment analysis (DEA) is applied to the decision for decreasing risk. The main works are summarized as following:1) The dangers the warship may encounter are clarified. Some methods normally used to identify these dangers are also clarified, such as FMEA, FTA, ETA. An example is presented to illustrate how to apply the FTA method to the hazard identification.2) Both the probability and the consequence are considered in the risk assessment. Two methods are used to quantify the risk. The first one is the method of risk contribution tree, by which the risk of the basic event can be quantified and the components of the risk can be depicted in detail. The second one is weighted fuzzy estimation, by which the theory of the fuzzy mathematics is used to quantify the risk and the process of the quantification is simplified. 3)With the various risks being considered, the measures are discussed to decreasethe risk.4) The assessment of the decision for decreasing risk is carried out by introducing the data envelopment analysis (DEA). The weight of the index values and the relationships among them need not to be known in advance. The candidate schemes can be assessed, only if the input values (cost) and the output values (benefit) are known, and then the best scheme can be selected.