A Model for Assessment Collision Risk Degree of Ships in Sight of Another

Ship evaluation factors of navigation risks are determined according to the principles of choice evaluation factors and the practical situations of ship collisions in sight of another. Collision risk assessment criterions have about three circumstances of crossing situation. These circumstances being head on taking situation and overtaking situation are established according to some ship collision data which will be analyzed. With the help of Delphi, Analysis Hierarchy Process (AHP) and Fuzzy theories, a comprehensive fuzzy mathematical model for assessment collision risk degree (CRD) with some subordinate degree functions can be constructed. According to comparisons with other BP network models and the truth, the present CRD model in this paper is practicable and credible because the CRD assessment results for many ships encountering are basically agreed with BP network model and the truth. The research indicates that the fuzzy mathematical model can provide some scientific decisions and references for ship commanders.