Some Analytical Rules for Job Mix Evaluation for Reactive Scheduling of Parallel Machines

平行機器反應式排程之工單組合評估的分析法則

Yon-Chun Chou(周雍強) ； Yue-Lan Lin(林玉蘭)

《中正嶺學報》 43卷2期 (2014/11) Pp. 17-28

摘要

Assigning jobs to parallel machines is a classic problem in manufacturing and computer science. In many manufacturing environments, machines availability and job orders might change dynamically. The aim of reactive scheduling is mainly to repair a previous schedule. Reactive scheduling requires fast methods and knowledge rules in response to unexpected events. This paper presents some analytical rules on the dominance relationships on job mixings under Poisson job arrival and a method for estimating machine workload when there are alternative machines. It is found that uneven mixings of job types are better than even mixings in reducing setup time. An iterative procedure is shown to converge in workload balancing and the resultant makespan. Workload can be estimated with accuracy without running time-consuming optimization programs. Applications are demonstrated with numerical examples.

關鍵字

setup avoidance ； load balancing ； job-machine assignment

並列摘要

平行機器的工單指派是常見的製造決策與電腦科學問題，在很多情況，工單的到達情況與機器的妥善狀況是隨時變化的，工單的反應式排程的主要目標是在發生不預期的情況，對既有的排程進行快速修補，這需要對工單排程的快速分析方法與知識法則。本文以普瓦松過程表示工單到達的不確定性，以分析法推導不同工單組合對設定轉換的機率，本文的第一項貢獻是推導出不均勻工單組合要優於均勻工單組合的法則，第二項貢獻是對工單指派的工作負載，推導出不必動用優化軟體的快速估算方法。這兩項結果提供快速解法，適合應用在反應式的工單指派問題。

並列關鍵字

設定減廢 ； 負載平衡 ； 工單機台指派