研究期間:10108~10207;In a sequential zone picking system or a synchronized zone picking system, a picker is not allowed to leave his/her zone and enter other zones. This restriction can cause a serious shortcoming in which some zones are very busy, while some are not or even idle. Another shortcoming caused by this restriction is the longer travel distance of pickers in a synchronized zone picking system. These two shortcomings can hinder the performance of the entire system. To avoid these shortcomings, we propose a cooperation strategy so that pickers of neighboring zones can help each other. The main task is to develop various cooperation methods and compare their performance so that the best cooperation method can be found. We will also discuss the issue of how to design zones and the cooperation zones to facilitate the cooperation between neighboring zones. We plan to complete studying the above problems in two years. The main steps of this research are briefly described as follows. (1) First, to have a better understanding of the problems studied here, an extensive survey of related studies will be conducted. (2) One then defines and models the problems. (3) The next step is to devise methods for these problems. (4) To understand the performance of the proposed methods, computer simulation experiments will be conducted. (5) The experimental results will be analyzed. The analysis result can help us improve the proposed methods. Finally, it is hoped that the results of this study can benefit distribution centers. It is also hoped that this study can provide some helpful insights in the related research.