A Single Row Layout Problem With Additional Clearances And The Algorithms

Facilities layout problems have been addressed in practice and theoretical studies for many years, and there are abundant versions and formulations in the manufacturing context. As a typical form of equipment layout, the single row layout problem has been extensively studied. The problem seeks the arrangement of a fixed number of facilities along one row that minimize the objective of total material handling cost. In production, the flow cost between two facilities is an important part of the cost. However, the area cost occupied by facilities is expensive, accounting for a part of total cost as well. This paper investigates the actual situation at home and abroad about the single row facility layout problem, and takes consideration of the area of the facility sequence as one of the research objectives, combining the basic production requirements, then proposes a new model:a single row layout problem with additional clearances. The clearances can be placed on both sides of facilities according to the demand. The new problem can be devised into two parts:1) The single row layout problem with additional clearances to optimize the flow cost. To solve this problem, a combination of tabu search (TS) and mathematical programming is proposed to solve this problem. In detail, the tabu search is used to find the sequence of facilities then mathematical programming is used to optimize the additional clearance for each facility. To enable a facility sequence in TS to be evaluated (that is, calculate its objective function value), a constructive procedure is devised and embedded into the TS to determine the additional clearance for each facility.2) The single row layout problem with additional clearances to optimize the flow cost and facility area. To solve this problem, we propose a discrete differential evolutionary algorithm based on integer.In order to verify the proposed models and the method proposed are correct and effective, the verification of small size instances (10facilities)> medium-size instances (20、30facilities) and large-size instances (50facilities) are shown in the paper. The result shows that the model can describe the demands and the proposed method can solve the model effectively.