Study On Railway Regional Network Wagon Flow Organization Optimization And Adjustment

With the fast development of global economy, exchange activity is developed synchronously in each field. The most outstanding one is the circulation of the goods and materials among areas. The current transportation mode mainly includes railway, waterway, highway, aviation and pipeline, which has formed multimodal transportation through crossing and permeating with each other. However, no matter which kind of transportation, it includes the process of gathering goods and turning into logistics. Railway transport dispatch is the conductor centre of daily transportation organization, which is responsible for organizing passenger-cargo transportation, guarantying the state transports safety, improving the service quality. With the cancelation of the railway branch office,the application of DMIS,TMIS and the appearance of new generation CTC technology, the current railway bureau deployment command area has been much more widened and concentrated, which also allowed the enlargement of the dispatch conductor managing ability. Therefore, the actual produce requires the proper division and regulation of labor work.Organization and adjustment of railway wagon flow are the foundation of the transportation organization work. Railway wagon flow organization refers to that according to the requirements of, such as line capacity and station capacity limitation, they can organize and compose all the cars and form the train marshalling plan to direct daily transportation and production. The optimization contains wagon flow trace and train marshalling plan optimization, which both belong to the combination optimization research area. Adjustment of railway wagon flow can prevent capacity waste, period olocking of line and station by forecasting, calculating and organizing.As the deep development of railway mercerization, the wagon flow unbalance is oeeoming obvious, which influences wildly and is much harder to adjust. To adapt to the unbalance wagon flow transportation environment, the thoughts and methods of the wagon flow adjustment must be changed. We must take certain methods to improve the strain capacity, quickly easer the influence of unbalance and keep a dynamic balance of auportation to maximize the whole transportation utility. This has been the most urgent problem for the dispatch conductor to solve after the concentration of railway deployment system.Optimization of wagon flow and organization has made an achievement. But the whole integration of two still need more research. In this dissertation, on the basis of research results at home and abroad, we considered the features of the railway transportation in China and did research on coordination between the sector railway wagon flow organization and adjustment. Here we proposed some methods and models to optimize dynamic wagon flow with practical application value, by which we hope to establish theory foundation for deep research of wagon flow in our nation.The main research work of the dissertation includes the following several respects:1. Considering the progressive relation of railway freight transportation, the flow of goods, wagon and train and the inner link between them has been analyzed systematically.2. By analyzing the determination of wagon flow routing and the compiling of formation plan, aimed at minimizing the cost of aggregation and line operation, a comprehensive optimization model of regional-network train organization has been formulated, which can help the determination of formation plan and the choice of train routing.3.Based on the emergence, significance, principle, classification and method of transportation adjustment, according to the principle of non-division and flow connection together with the constrain of line capacity, a collaborative optimization model of loaded and empty wagon flow been formulated aiming at minimizing the total cost of empty and loaded wagon transportation. It overcame the defect of separation between the loaded and empty wagon flow transportation in traditional way, met the wagon organization requirement of our nation with non-division principle and arrived at a more concrete allocation scheme by taking the related parameters between the category of goods and wagon into consideration, which determined that the empty wagon could be allocated only when there were suitable goods.4. On the basis of constructing the space-time network, the global optimization models of regional network wagon flow organization and adjustment named SOMCOR has been formulated. Following the structure feature, the solution to the model uses the integer constraint of slack variable of locomotive as the nonnegative constraint to get the model SOMCOR*. Meanwhile, it divided into two sub problems depending on the type of decision variable. The one was wagon flow organization optimization model named OMCO whose objective was the minimum cost of locomotive. The other one was wagon flow adjustment optimization model named OMCR which aimed at the minimum cost of empty and loaded wagon flow adjustment. The optimal solution to the two sub problems formed the upper bound of optimal solution of SOMCOR while the optimal solution to SOMCOR*as the lower bound. As a result, the upper and lower bound determined the range of optimal solution of SOMCOR.5. A designed ant colony algorithm was applied to the solution to the comprehensive optimization model. Testing by the data from Chengdu Railway Bureau, it was proved that the algorithm could adjust wagon flow in a short time, which well demonstrated its availability and practicality.