考量彈性因素下多目標設施佈置之研究

Abstract

設施佈置規劃的優劣，不僅影響系統之運作順暢與否，更透過物料搬運成 本的影響，成為決定生產成本高低的關鍵因素之一。 本文提出一 多目標設施佈置模式，同時考慮影響設施佈置的定量因素（設施間的物料 搬運成本）及定性因素（設施間的相關程度），利用一成本參數對設施間 的相關程度加權，藉以降低兩目標函式因值域的差異所造成的影響，使個 別目標值間的品質趨於一致。在進行規劃的過程中，並考慮生產水準發生 變動的情況，此即所謂設施佈置的 " 彈性 "。文中利用損失成本來衡量 設施佈置的彈性，損失成本愈小，代表此佈置方案愈具彈性。最後提出一 兩階段的演算法，第一階段利用CRAFT求得規劃週期內各期之近似最佳佈 置方案，以作為計算損失成本的依據；第二階段則以模擬退火法來求解規 劃週期內最具彈性的設施佈置方案。 The result of facility layout will influence the performance of production system and is the key factor of deciding production cost. This paper presents a multi-objective facility layout model for combining quantitative factor (material handling cost) and qualitative factor (closeness rating). In this model, closeness rating is weighted by a cost parameter in order to reduce the influence of difference between two objective functions, and let the quality of individual objective be close each other. During the programming procedure, consider changes in production level, this is "flexibility" of facility layout. In this paper, we use lost cost to measure the flexibility of a layout. The lower the lost cost is, the more flexible the layout is. Finally, this paper presents a two-phase algorithm to solve the flexible facility layout problem. In phase one, CRAFT is ployed to obtained the suboptimal layout for each period. Using these suboptimal layouts, the lost cost of each period can be caculated. In phase two, the most flexible layout during planning horizon can obtained by using simulated annealing algorithm.