Summary: | 博士 === 國立成功大學 === 工業管理學系 === 89 === Abstract
This study is concerned with jointed cell clustering-layout problem in which the cell formation and the intercell layout are determined simultaneously. The machine cells are to be located along two popular material handling facilities, i.e. the unidirectional unicyclic loop network and the linear single-row bi-directional layout. The decision parameters include demand data and routing sequence of parts, processing time, unique and duplicated machine types, and machine capacities or workload. The objective of the joint problem is to minimize the actual intercell flow cost, instead of the typical measure that minimizes the number of intercell movements.
A three-phase heuristic approach is proposed to solve the jointed problem when the unidirectional loop network is considered. In this approach, the intercell flow cost function is reformulated as a weighted criterion and a divide and conquer algorithm is proposed to quickly estimate the intercell movement cost. The workloads of machine are assigned in the formation process. For the bi-directional linear flow layout, a two-phase approach is developed. The jointed problem has been transformed into a multi-terminal network flow model. A cut tree is then constructed and partitioned the machines into a number of cells, and their layout sequences are assigned by comparing the cut capacities.
Computational procedures are illustrated with examples and additional experiments are performed with 32 cases, which are adapted from the literature. The numerical study has shown that the approaches are effective and efficient. It also reveals that the cell formation and the material flow feature should be jointly considered when layout or material handling information is available. The two approaches can also be extended to address the cell formation problems when different types of layout or duplicated machines are considered.
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