| Dock erection plays an important role in shipbuilding process.When more ships equipped with dock resources,reasonable arrangements of hoisting sequence and hoisting time for each section,use the resource balance to reduce conflict is a key problem that the shipbuilding enterprise must consider and solve carefully in preparing the ship’s hoisting plan.The section hoisting scheduling optimization problem on the dock of multi-ships as the research object,through arrange the hoisting sequence and hoisting time of sections reasonable,so as to improve the efficiency of erection and shorten the period of dock.Research work and conclusions were mainly included as follows:(1)The operation flow and characteristics of section hoisting on the dock are described.Introduced the importance of stage-loading hoisting work plan,and expounded the key problems of section hosting scheduling from the three aspects of embark method,section process constraints and resource constraints on the dock.(2)According to the scheduling process of the multi-ships section hosting,described the optimization of section hoisting sequence problem on the basis theory of the resource-constrained project scheduling problem firstly;Then,the optimization model based on the theory of "limited resources-minimum duration" which target is minimized the sum of post-weld period for dock erection of multi-ship was established.Finally,described the relevant theoretical knowledge of genetic algorithms,improved the performance of standard genetic algorithm for the lack from the angle of dynamic determination of population size and cross mutation rate and the implementation process and design method of genetic algorithm for solving the problem were given.(3)Based on the hoisting scheme of four 64000 DWT bulk carrier,the optimization of multi-ships hoisting schedule in the double constraints of section process and dock resources was solved by the improved genetic algorithm for Matlab language programming.By compared with the initial plan of the enterprise,it is verified that the method proposed in this paper is completely practical.The method has important practical guiding significance for enterprises to formulate the dock erection hoisting plan,improve the efficiency of erection and shorten the period of dock.(4)For the convenience of the enterprise actual work needs,developed the section hoisting scheduling optimization toolbox based on Matlab GUI platform,to realize the platform operation of section hoisting scheduling problem on the dock which was solved by the improved genetic algorithm.Taking the hoisting plan of four 64000 DWT bulk carrier as an example,the toolbox was verified to be feasible and practical through comparative analysis of the output results,which was provided a new idea for the enterprise to adopt the improved genetic algorithm to solve the optimization of section hoisting scheduling problems. |
