基于改进型AHP与证据理论的应答器系统风险评估

Risk assessment of balise system based on the improved AHP and evidence theory

为了科学客观地对应答器系统进行风险评估,规避评估过程中的主观性和不确定性,提出了一种基于改进型AHP与证据理论的评估方法。首先识别系统的风险因素,采用改进型AHP法确定风险因素的权重;然后依据权重将模糊子集引入证据体空间,并加入模糊概率,将专家的模糊描述转换为定量描述,利用证据理论合成规则得到系统风险的mass函数值。最后,以应答器系统为例进行风险评估,结果表明,该方法的评估结果与实际情况基本吻合,验证了该方法的可靠性和有效性。

In order to provide a scientific and objective assessment of the risk of balise system and avoid subjectivity and ambiguity in the process of assessment,this paper intends to bring about a method for such assessments by joining the improved analytic hierarchy process(AHP)with the evidence theory.For this purpose,we have,first at all,identified the risk factors of the research goals,and,then,we have managed to ascertain the weights of each risk index via the improved AHP method on the basis of each risk factor,we have been trying to establish the fuzzy subsets and introduced them into the evidence embodiment areas.By adding the fuzzy probability,we have also transformed the fuzzy descriptions given by the expertise judgment into the quantitative description.Furthermore,we have also combined the rule of the evidence theory with the mass function indexes of the system risk.Last of all,we have taken the balise system as a practical assessment sample to verify the aforementioned methods to identify the 21 risk factors for the lane side electronic units(LEU).In addition,the paper has also made a detailed description to heighten the analysis operability,the ground balise,the antenna unit and balise transmission module(BTM)by analyzing the structure and function of the said system as well as the analysis process,in which the mass function indexes has been made in strict correspondence with the“acceptable”,“admissible”,“undesired”and“unacceptable”ones of 0.001 7,0.805 8,0.192 5 and 0.Besides,the risk indexes of the balise system has been made well accepted and admitted with the weak links being on-board transmission device on account of the maximum membership degrees.From the above mentioned research,it can be concluded that the analysis results offered in this paper should turn out well in accord with the actual situation of the balise system.Thus,this assessment model should be not only reliable and effective in determining the weights,but also applicable and practical in dealing with the fuzzy process and the uncertainty information.