Research Of Mission Reliability Evaluation Method For Ships

With the increasing degree of modernization, the modern ship has also become a high-tech product, also a complex system. Research of mission reliability evaluation method for ships has great application value not only in the field of military technology but also in the field of civilian technology. Mission reliability is an important performance indicator concerned by the use department and the production department. Therefore, research of mission reliability evaluation method for ships has great application meaning.To small sample, maintainable and large complex system just as a ship, how to apply the meaning of reliability indicators to the evaluation method, establish rational reliability evaluation model scientifically, and carry out ship system mission reliability evaluation, are research keys for both the use department and the production department. Based on a brief review of the characteristics of ship system and the reliability relevant theory, the paper discusses the reliability evaluation theory and analysis methods. Through analysis and testing of a variety of sources of reliability information, the overall mission reliability information is treated; through the fault tree analysis and minimum cut-set analysis, the overall mission reliability model is established;through Bayes fitting reliability evaluation method, the overall mission reliability lower limit and specific MATLAB statement are given to solve the complex system, small sample and calculation difficulty problems. These are effective and feasible reliability evaluation methods for a ship system and other large complex equipments, which have great significances for ship design, optimization and improvement.The contributions of the paper lie in:a) Pre-processing different sources of reliability data, according to the multi-sources, high-cost and small-sample nature, through a certain way to make full use of all kinds of reliability data and expand the amount of reliability evaluation data, a reliability data platform is provided for the ship overall mission reliability evaluation.b) Establishing the overall mission reliability evaluation model, according to the typical task model, the task is divided into different task stage, fault tree analysis and the minimum cut-set analysis are done for each task phase. All the minimal cut sets of all the mission phase are connected in series to the overall mission reliability evaluation model.c) Evaluating the ship overall mission reliability, using Bayes thought and fitting moment theory, overall mission reliability lower confidence limit and specific MATLAB statement are given, which are demonstrated by a example.