基于Dempster合成法则的空管安全评价方法研究

Approach to the aviation and air traffic and transportation safety evaluation based on the Dempster’s combination rule

随着我国民航运输业的蓬勃发展,空中交通管理工作的安全压力日益增加。由于空管安全评价中存在大量的不确定性,如随机性、不精确性和模糊性,提出了一种将证据理论引入空管安全评价工作的新方法。首先对证据理论的核心内容——Dempster合成法则进行了分析,并对＂改进式Dempster合成法则＂进行了详细说明;其次,建立了空管安全评价的3阶安全评价指标体系,使用层次分析法确定了各指标的权重,并在此基础上建立了基于证据理论的安全评价模型;最后,通过空管安全评价算法,深入探讨了模型的可行性,并通过风险计算公式得到了空管系统存在的安全风险值,从而有效地保障空管安全评价工作的效率和准确性。

This paper intends to introduce the D-S evidence theory into the safety evaluation of the air traffic and transportation safety control. As is known,the great uncertainty with the safety evaluation has brought about to the air traffic control,which involves its randomness,imprecision and ambiguity,thus forcing us to work out a new method in this paper. For this purpose,we have,first of all,made a detailed analysis over the actual nature and the principle of the evidence theory—Dempster＇s combination rule. To gain the highly improved reliability in the air control practice,it is necessary to assign the basic reliability data to each proposition so as to build up a weight vector of evidence,known as ＂the Improved Dempster＇s combination rule＂. In so doing,it is necessary to get rid of the defects of the Dempster＇s combination rule,for its introduction may involve more or less inevitable contradictions. And,secondly,starting from the point of view of the principle of systems engineering and SHEL model,China＇s air traffic control safety appraisal involve 4 aspects,that is,＂man power,hardware,environment,and the management. ＂ Seeing the problem,we have built up a 3-aspect safety evaluation index system for the air traffic control safety evaluation,which involves the application of brainstorming method and the hierarchical analysis process,so as to determine the weights of each index in the practice of application. And,finally,it is necessary to refine the safety evaluation algorithm of the index system in terms of the following three ways： the reliability distribution of each factor has to be worked out through calculation of the index system via the basic reliability distribution function; the reliability dependability of the safety risks in the air traffic control system has to be worked out by using the improved reliability function; and,the safety risk probability evaluation of the air traffic control system 0. 407 5 has to be worked out by using the risk calculation formula by using the＂Improved Dempster＇s combination rule＂. It is just the aforementioned 3 kinds of calculation that can help to accomplish the in-depth discussion on the feasibility of the safety evaluation model. At the same time,the availability of the given model can only be verified in its dealing with the uncertainties in the said air traffic control safety.