Study On Railway Information Autonomous Integration System Based On Service Flexibility

Information systems have covered the whole railway transportation field, but with the development of railway, information techniques and user requirements, railway information systems need to adapt to the development. This thesis analyzed the existing railway information systems from three aspects, such as the development of network technology, the existing systems performance, and enterprise strategy. Hence, the development objective about our national railway information system has been described, the newly information service system should have the information integrating ability, the on-line expansion ability, and user-oriented ability. This thesis, aiming at railway information system, based on the discussion about organization and structure forms of the existing railway and the Passenger-Dedicated Lines (PDL), has studied the newly railway information service integration system which is described above.Firstly, aiming at the integration problem of legacy systems, this thesis combines the service scientific concept with ADS (Autonomous Decentralized System) theory, utilizes the expansion properties of ADS effectively, and proposes the concept of Service-Oriented ADS (SOADS). This thesis completes the description for Service-Oriented Autonomous Integration Architecture (SOAIA), and describes its hierarchy model and autonomous service meta-model. For the Autonomous Service Bus (ASB), it is the key of service quality assurance in SOADS, the thesis designs ASB structure, and describes service flow and its basic assurance facilities. In order to construct and implement SOADS, this thesis proposes the definitions about autonomous integration node and autonomous subsystem, describes the forming process of SOADS via AINs, designs autonomous navigation mechanism based on message-driven model, and gives out the system engineering mapping method of Autonomous Functional Unit (AFU) and Autonomous Information Field. SOADS provides the architecture support for the research of this thesis.Based on the SOADS concepts and model, the thesis also discusses its application on the algorithm ensemble field. In order to utilize idle and distributed computing resources which exists on the networks, this thesis proposes NN ensemble model based on SOADS, designs the communication timeline mechanism, and gives out the training algorithm which is used to accomplish dataset allocating and result collecting autonomously, the experiment results demonstrate the model's generalization and classification ability.Service flexibility is the concept in the field of management science, this thesis proposes the definition of information service" flexibility, defines the measurement method for information flexibility, and finishes its formal description, and then the thesis proposes the information flexibility separating strategy, and the relative Information Flexibility Descending Field (IFDF). The thesis introduces the relative technique of IFDF, such as hierarchy rule, integration mode, and the application advantage. Then, the thesis forms a new SO ADS model based on the information flexibility strategy, discusses the communication technique implemented by Content Code (CC), and discusses service request sending and result collecting by the Pull-MA and Push-MA. In order to test the system responsibility, the newly service-based model's responsibility has been compared with the server-based model via REPAST tools; the result has demonstrated its effectiveness.In accordance with the theory and technique methods of IFDF and SOADS, Railway Information Service Flexible Integration System (RIIS) has been constructed in this thesis. The formal description of RIIS service model is finished which has been used to construct a Petri nets model, and the file transmission service standards is designed, all those can be used to test and verify semantic consistency and accessibility of a information service. In the thesis, the RIIS logic model is formed, and a dynamic logic processes example about train dispatching is given out.In order to improve the expansion and evolution abilities of service knowledge repository, the theory and methods of ontologies has been utilized in RIIS, the thesis constructs RIIS distributed ontology repository based on IFDF, talks about the mode and hierarchy architecture of RIIS distributed ontology repository, and forms the diverse size-level service ontology repository. In order to realize the information service, this thesis proposes service information ontology based on characters, defines and finishes ontology model description.Based on the ADS theory and technique, service science philosophy, and ontology theory, the thesis has proposed and studied the novel RIIS, the novel system's on-line expansion ability, integration ability and user-oriented can be assured. The thesis selects railway electrical emergency response service information integration system as the subsystem of RIIS, gives out the system model and implementation example based on the research results, the example's abilities can be assured.