Research On Resouce Scheduling Problems During Ship Block Assembly Process

In moden shipbuilding mode, ship block assembly process has a longproduction time and multi-resource constraints, which is the bottleneck of theentire shipbuilding cycle. Thus research on how to optimally schedule therelated resources during the ship block assembly process would help tomanage and control the shipbuilding process, shorten the shipbuilding cycle.It is a key to improving the productivety and competitiveness of shipbuildingenterprises.The ship block assembly process can be viewed as including: assemblingin ship block assembly workshop, repairing in ship block storage yard andship block transpoortation therebetween. The ship block assembly process isdifferent from normal production process because of the requirement ofspatial resource, such as, assembly space, storage space and the space fortransportation. Besides, working teams for assembling work and flattransporters for transporting work are also very important resources. Withrespect to the above analysis, the main contents of this dissertation areoutlined as follows:(1) For the spacial resource requirement in ship block assemblyworkshop, analyze on the characteristics of shape of ship blocks, and proposea method to handle spatial cosntraint. Based on the three dimensionaltime-spacial model, a new positioning algorithm is proposed and improvedreferencing to the three-dimensional packing algorithm. The objective of thealgorithm is to optimize the time and spacial resources in ship block assembly workshop simultaneously.(2) For the limited resource of working teams which are the units of shipblock assembly work, and the differences in the technology and the ability ofeach working team would lead to the asssembly time of ship block uncertain,a combinational mathematical model of the spatial scheduling and theworking team assignment is built, with the multi objectives on both thetime-spacial optimization and the workforce balance. A method combininggenetic algorithm and the time-spacial positioning algorithm described aboveis proposed for a better scheduling plan in ship block assembly workshop.(3) One of the key factors that cause traffic jams in shipbuildingenterprises is the unresonable spacial resource utilizaiotn in ship blockstorage yard. With the objective on minimizing the block temporarymovements in the ship block storage yard, research on the locationassignment algorithm, the temorary movement strategy and the ship blocksequence optimization is made in order to meet the time and spacialrequirements of storing ship blocks and the space and path contraints of flattransporters.(4) In order to transport ship blocks among different locations, thetransportation scheduling problem considering multi cars for one object at atime is researched. Since the quantity and ability of flat transporters arelimited, an optimization scheduling model and method are proposed with theobjecitve to minimize the logistics time, which includes the nun-load time offlat transporters, the waiting time and the delay time of ship block tasks.(5) Considering the practice of ship block assembly management inshipbuilding enterprises of our country, a ship block scheduling system isconstructed. Take the data of the ship block assemly process in one of the shipbuilding enterprises for example, the resource scheduling methods areillustrated to meet the actual requirement of the shipbuilding enterprise.