Two-Machine No-wait Openshop Scheduling Problem

• Main Authors: Po-hsiu Chen, 陳柏秀
• Other Authors: Ching-Fang Liaw
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/58804559741516615119

碩士 === 朝陽科技大學 === 工業工程與管理系碩士班 === 91 === The openshop scheduling problem can be stated as follows. There are n independent jobs and m different machines. There is no restriction on the order in which the operations of a job are to be performed. Each machine can process at most one job at a time and each job can be processed on one machine at a time. Examples of openshop problem include teacher-class timetabling problem, health examination and the operate of car maintenance. Scheduling problems with no-wait constraints occur in many industries. For instance, in hot metal rolling industries , where the heated metal has to undergo a series of operations at continuously high temperatures before it is cooled in order to prevent defects.Similarly , in the plastic molding and silverware production industries, a series of operations must be performed to immediately follow one another to prevent degradation. We consider the problem of minimizing makespan in a two-machine no-wait openshop environment. In our research, we present a heuristic solution method for solving large-scaled problems. We also develop a branch and bound algorithm. We use an upper bound based on a heuristic algorithm, and discuss new dominance rules to help pruning unpromising nodes in the branch-and-bound search tree. Finally, computational experiments are conducted to evaluate the performances of the heuristic algorithm , upper bound, lower bounds, and branch-and-bround algorithm.