Operation safety evaluation system of ship lock based on extension evaluation and combination weighting method

Abstract Ship locks are the most widely used, promising, and important type of navigation structure in world at present. It is, therefore, crucial to evaluate operation safety a ship lock service. However, determination indicator thresholds is challenging. Accordingly, this paper describes systematic study evaluation system safety. First, accidents counted. According rhombic thinking mode (that ‘first divergence then convergence’), with help extenics, multi-indicator hierarchical including 5 first-class indicators 47 second-class for established, 4 grades classified: normal, deterioration, early warning, shutdown. The threshold range each grade determined individually. Second, based on idea multi-factor optimization integration, process matter-element model extension theory proposed. Then weight by combination weighting method. result consistent actual situation.