Research On Navigation Co-scheduling Of The Three Gorges Dam And Gezhouba Dam

With the large-scale and complexity of systems increasing, the large-scale complex scheduling has become one of the hotest problems. Based on the background of the project on the co-scheduling systems engineering of the the Three Gorges Dam and the Gezhouba dam, the network scheduling with the uncertainty is discussed and the methods of modeling and optimization for these networks are studied.As the Golden Channel's gorge of the Yangtze River, the Three Gorges reach from MiaoHe to ZhongShuiMen is 59 kilometers, where is the location of the hinge of the Three Gorges Dam and the Gezhouba dam. In order to improve the navigation capability for the establishment of the double-line five-grade ship locks of the Three Gorges Dam and the three one-step ship locks of the Gezhouba Dam as one whole framework, the co-scheduling of the Three Gorges Dam and the Gezhouba dam is implemented for all the ships to pass the dams expeditely. Effective navigation on the Golden Channel's gorge is bound to be of great benefit to the Yangtze River economically. According to the work on the scheduling problems and the experience from the administrative bureau, the more effective models and methods are presented, so as to offer the new research and methods for the scheduling of the transportation on the highway, railway, and voyage.In this dissertation, in order to make the co-scheduling as efficient as possibly and provide the design and betterment of the co-scheduling with the theoretical approaches, my research is foused on the mathematic model of co-scheduling, the strategies of co-scheduling, the rolling interval scheduling under uncertainty, arrangement outside of ship locks and the adjustment for scheduling.The main research work lies in five aspects as follows.(1) Navigation co-scheduling system is studied, and the mathematical model is set up with the definition of objective function and the corresponding restrictive conditions, and the mathematic model of co-scheduling is described as a multi-objective non-linear programming problem. Solving the Three Gorges Dam and the Gezhouba Dam co-scheduling model is based on the timetable sequence deduced from the ship sequence, in this sense, this is a scheduling problem of the time table from time aspect. The ship needs to be arranged into the two-dimensional space(arrange ships) in accordance with the timetable of the sequence (the arrangement answer includes the location information of the ships in the ship lock), that is, a bin packing problem from space aspect. The two problems are coupled as a NP-hard combinatorial optimization problem, and the actual shipping scheduling system variables in the structure is complex and precise, and optimization algorithm is unrealistic. Therefore, in view of the scheduling model objectives and constraints, the progressive optimality algorithm is designed, which is fit for the multi-stage decision-making for a method of using multi-cycle iterative optimization strategy with multi-constraint problem.(2) The best strategy is the centralized scheduling coupled with distributed scheduling. From the distribution of the five dams, they build a network. The nodes of the network are linked by the ship flow, and are bound respectively by the location of the dams. There is 38 kilometers between two dams, distributed scheduling is accepted considering the long distance between the two dams, and it is close to the scheduling at spot. Distributed scheduling is convenient to make the navigation capability maximal, and the shortcoming is that the interlinkage between the two dams is problematical to make the ships overstocked between dams. Centralized scheduling is adopted considering the short distance between the two dams, that is the united scheduling for all ship locks. The advantage of the centralized scheduling is good to the interlinkage between the two dams, and it is lack of the maximal navigation capability because of the restricted dam. By the comparison analysis of the two strategies, based on full analysis of Three Gorges-Gezhouba dam's actual needs, the best co-scheduling of the Three Gorges Dam and the Gezhouba Dam with the area buffer and the time punishment is introduced.(3) It is chaos for ships to pass the dams by by the small data sets method in chaotic time series analyzing, predicting interval is obtained to keep the scheduling plan precise, according to the method of the the rolling scheduling with the appropriate rolling interval, the rolling interval scheduling which can satisfy the spot scheduling better is presented. By means of experiment's analysis, illustrative results show that the the rolling interval scheduling is feasible and the the scheduling plan deduced from the algorithm is quite close to the schema in practice. The rolling interval scheduling can make the more accurate scheduling plan to instruct the spot scheduling, and can significantly improve the throughput of the ship locks.(4) With focus on the whole process of the co-scheduling to optimize the ship scheduling, a new concept of the arrangement outside of the ship locks and the adjustment for scheduling are introduced. Based on the analysis of the operation process of ships'entry into ship locks, the mathematic model with the objectives of the safety and the time for entry into ship locks is established, followed with a corresponding heuristic solution algorithm, which can heuristically educe the arrangement approach for the ships outside of the ship locks through the objectives and constraints in the model. During the spot scheduling, the adjustment for scheduling is used to optimize and meet the emergency, and it is the arrangement inside compared with the arrangement outside. By means of experiment's analysis, illustrative results show that the arrangement outside of the ship locks and the adjustment for scheduling are feasible. Considering the time for ships'entry into ship locks and the principle of safety , two strategies can increase the operation times of ship locks, and can make the efficient scheme for ship scheduling.At last, the navigation co-scheduling system is designed and developed by the author, involving the navigation co-scheduling module and navigation information management module. Based on the mathematic model, the strategies of co-scheduling, the rolling interval scheduling under uncertainty, arrangement outside of ship locks and adjustment, the co-scheduling system has worked for two years. The results show that it is general and adaptive for co-scheduling system to make the practice and theory combined. The research on the co-scheduling systems engineering of the the Three Gorges Dam and the Gezhouba dam can solve the problems in practice, at the same time, can offer the certain methods of the network scheduling with the uncertainty.