The Probe Of Fault Diagnosis Method Of Urban Road Intersection

Survey found that the existing fault diagnosis research of urban road intersection are inadequate, and significantly, the intersection as the important node of urban road traffic network influence the traffic system’s "life-cycle". Deficiency in traffic fault diagnosis theory makes the lack of a method or thought for guiding the traffic administrative Department to improve and solve city traffic problem, avoiding helpless or worse handling when facing the existing traffic problems. This paper preliminarily explores fault diagnosis method of Urban Road intersection, aiming to establish an ideological method of traffic system for transportation system engineering, selecting appropriate technical methods and means for improvement and optimization of urban road traffic system.Deeply studying the links among the transportation system, transportation system engineering and traffic system methodology, the traffic system methodology guides and includes method of transportation system engineering and transportation systems engineering method is to deal with the problem of traffic system and to optimize traffic system, traffic system exists as the theory of vector of traffic system methodology. Therefore, in order to solve the traffic system problems, we must first find out a set of scientific and suitable for the methodology, this paper researches the characteristics of transportation system and compares analysis of the differences between the hard systems methodology and soft systems methodology and their respective advantages and disadvantages, and ultimately determine the Checkland soft system methodology as the theory base of traffic system, under the guidance of the theory, choosing the fault diagnosis method based on the Signed Directed Graph to solve the technical problem of fault diagnosis of the existing urban road intersection.Analysis of the characteristics and classification of traffic fault serves as reference to select a method of fault diagnosis, based on meeting the traffic fault diagnosis principle and evaluation standard, choosing the fault diagnosis method based on the Signed Directed Graph (SDG) as the technical means. The method in fault diagnosis of intersection exists great superiority and feasibility and clears fault diagnosis process and priority, on the basis of actual cases, presenting the established SDG model of the common intersection faults.The project’s real case tests research results and the accuracy of the model, appropriate adjustments makes the SDG fault diagnosis method more suitable for the fault diagnosis of Urban Road intersection. The case analysis confirms the system methodology’s theoretical core and guiding significance in handling traffic system problem.The fault diagnosis of urban road intersection is based on Signed Directed Graph as the technique method, and the SDG fault diagnosis model is established under the guidance of the traffic system methodology thought, and the fault diagnosis is carried out according to the diagnostic process. Fault diagnosis method of urban road intersections will influence the field of traffic enormously and promote the formation of emerging industries in transport sector, conducive to resolving the facing severe traffic problems in the road network of large-sized and medium-sized cities in China.