A Study of Storage Assignment with Multi-Pickers and Congestion Considerations

• Main Authors: Pei-Hsum Tsai, 蔡佩訓
• Other Authors: Chao-Hsien Pan
• Format: Others
• Language: en_US
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/78437136852760490826

碩士 === 國立臺灣科技大學 === 工業管理系 === 92 === Order picking is an essential operation and is the major cost constituent of distribution center. Generally, there are three significant warehouse policies decisions that determine the efficiency of order picking, picking routing, storage assignment, order batching. Previous research has focused on either picking routing or order batching, but this thesis attempts to reform order picking efficiency based on storage assignment. In efficiency measurement, previous research has generally used travel distance to measure order picking efficiency, because the order picking system only considers single-pickers. Congestion inevitably exists when the system has multiple pickers working together within the same region. Consequently, the travel distance is not suitable for estimating picking efficiency in a multi-pickers problem, and thus travel time is used to determine system efficiency directly. This thesis attempts to develop a storage assignment policy of heuristic, which must simultaneously consider travel distance and workload of each aisle. The objective is to minimize mean travel time of an order. The paper compares the mean travel time for different storage assignment policies, namely frequency-based and heuristic policies. The simulation results show that the heuristic policy is better than the frequency-based storage assignment policy.