Research On The Reliability Of Railway Logistics Service System Based On Stochastic Service Process

The railway, as artery of China's economic system and backbone of comprehensive transportation system,is the important link in the social logistics service system. Under the market economy condition, the people's demand for the cargo and goods'needs for logistics services (loading and unloading, transportation, distribution, circulation processing etc) are random. Also, stock with goods of railway freight transportation system and transportation logistics needs, as important links of social logistics service system, are random. While transportation capacity was nervous, railway mainly carried out planning transportation services. It was lack of research about stochastic service providing random demand in logistics market. Facing the important transition and development opportunities of division of railway passenger and freight and release of railway potential transport capacity, it is in the railway enterprise urgent important problem of how to improve the logistics service quality, to provide more efficient and reliable logistics service, to meet the randomness requirements of society which is under the market economy condition, and to improve market competitiveness. Based on stochastic service theory and information technology and other related theories and methods, this article constructs queuing model of railway logistics service system reliability, and study railway logistics nodes reliability and railway logistics network reliability. Through the comparison of reliability indexes, the text gets a system with optimal service efficiency and higher service reliability, and then uses the information system to reduce uncertainty from stochastic system. As a result, it can provide decision and support for the operation and management of railway enterprise. This article make a systematic research and exploration on railway logistics stochastic service system reliability from the following several aspects.(1) Analysis of tructure and characteristic of the railway logistics service systemThrough analysis of railway logistics service system employing methods of system theory, the following conclusion can be reached. In the situation of division of railway passenger and freight and release of railway potential transport capacity,at the same time in railway network coverage of time and space, the railway logistics service system is an organic whole with mutual connection and interaction. It is composed of the railway logistics service staff, railway logistics nodes, railway logistics network, and the railway logistics information system. Through the definition of the railway logistics service system, the structure and properties can be analyzed. It constructs a theory or model adapting to its structure and characteristics, and extracts the basic theory framework of current railway logistics service system reliability research.(2) Research on queuing model and reliability of the railway logistics service systemAccording to the characteristics of railway logistics service system, queuing model based on stochastic service system theory of can be constructed. With the system reliability measure system, on the base of analyzing typical queuing model of M/M/1/∞, it gives queuing model of GI/G/n/oo type of the general services and general arrival. On the basis of existing qualitative derivation, according to the characteristics of railway logistics service system, the quantitative analysis of different model reliability can be concluded.(3) Research of services reliability of railway logistics nodes queuing systemIntroducing continuous queuing theory into researches of services reliability of railway logistics nodes, it is concluded that M/G/n/∞queuing mode of railway logistics nodes of the general services distribution. Through classification discussion of the service interval time distribution for Erlang flow, adjust flow and Poisson flow, the system efficiency can be solved respectively. So it can be a conclusion that the railway logistics nodes service system with optimal reliability efficiency and higher system reliability is the system whose service interval is adjusting flow. By computer simulation, the theoretical results and computer simulation results are basically the same.(4) Research of services reliability of railway logistics network queuing systemBased on deducing and improving the theory of logistic unit network, combining research conclusion of logistics nodes queuing model M/G/1/∞, it constructs the railway logistics network queuing model M/G/1/∞/N. And respectively solves service reliability and service efficiency of railway logistics service system when the service interval is Erlang flow, adjusting flow and poisson flow. Through analysizing the calculation results of the queue length, queuing waiting time and other measuring indexes of queuing system, it can be concluded as follows. Under the premise of arrival flow for poisson flow, M/D/1/∞/N queuing model whose service time interval distribution is adjusting flow has higher reliability and superior service than the M/Ek/1/∞/N ror M/M/1/∞/N queue model whose service time interval distribution is Erlang flow or poisson flow.(5) Optimization technology of the railway logistics service system's reliabilityUsing information systems and peripheral object networking docking, with theories and technologies such as the data mining technology, customer relationship management theory, supply chain cooperative technology and physical networking technologies, valuable information of large and complex things networking and plenty of basic data from TMIS and DMIS etc, and related information can be analysized and used. So function of information sharing, real-time information transmission, information coordinated management, and decision support can be satisfiedly realized. Service flow of the railway logistics service system is improved to adjusting flow, as well as M/M/n/∞/N queuing model converted to M/D/n/∞/N queuing model. So that it can reduce the uncertainty of randomness in system, achieve best reliability, increase efficiency and reduce cost. Information system can also raise reliability of the entire supply chain system, and better meet the social needs.