Research And Application Of Simulation On The Tugboat Whole Allocation In Port

By understanding and realizing the system that is on studying, the The Discrete Event System Simulation taking out some key parameters from the system, establishing simulation model resemble to realistic system. Carrying through the simulation experiment on system model by the technology of data collecting and statistics analysing, imitating the running process of the system, observing the system state variableness dynamic regulation with the time change, estimating the reality parameter of the system and measuring the system performance, which will provide evidence for assistant decision.In the port, the ships passes in and out the harbor demand tugboat drag, the ships passes in and out the harbor event is a typical DESS(all the ships size, the ship tonnage, the time of ship passes in and out the harbor are random), which will bring the certain difficulty to reasonable marshaling for ship team. One side ,the unreasonable marshaling may result in the longer waiting time of the port ships, and it may result in the lower efficiency of the tugboat, accordingly waste the port resources. For the sake of adapting the port development, it is important to put forward reasonable project for quantity and horsepower of tugboat after studying on tugboat optimization marshaling. On the base of analyzing the Regulation of port tugboat working, this paper establish simulation model of tugboat working process by the principle of the DESS, and realize the model with object-oriented method. The paper run 10 kinds of to combine projects of the port may take place now or further, and get the port tugboat working characteristic values, for example, the waiting time of ships ,the max long of ships team, then analysis the output of simulation by and do some performance evaluation, finally, so as to calculate the best project of marshaling for tugboat to run normally in port, this paper carry through fuzzy-optimization by the method of fuzzy-synthetic judge with multi objective.For the particularity of the the port's tugboat working process , It's difficult to set up simulation model of the port's tugboat working process by the traditional single service stage and multi service stage theories. This paper set up the model with the queue theory, the simulation policy of Event Scheduling and the method of Flow Chart.It's a typical example of multi-objective-optimization optimization design tooptimize the outcome of simulation running. The DESS can't optimize the project of the tugboat allocation, So it must run the simulation program with many allocation projects, and get the best project after evaluating all the project outcome. For the factors affect simulation outcome uncertainly and fuzzily, this paper will optimize the simulation projects by multilevel fuzzy-synthetic judge that get from the combination of fuzzy technique with classic synthetic judge theory.On the above theories foundation, this paper will program simulation software for the port's tugboat marshaling, at the moment of designing, for the consumer's convenience using, the software will save and maintenance the large data of simulation running by adopting the technique of database. The simulation software not only provide applied tool for optimizing the marshaling of port's tugboat, but also verify the validity of the simulation model, so it has practical worth and theory worth in certain engineering.