中文摘要：

在当今的自动化制造系统中，计算机控制的抓钩的排序直接影响系统的生产率。本文研究了产品在系统的一边装载、而在另一边卸载的电镀线周期性排序问题。工件在每个工作站的处理时间在给定时间范围内，工作站之间没有缓冲槽，相同轨道上的两个抓钩用于工作站之间工件的运送，目标是对运送进行排序以极小化生产周期。为了求解这个问题，本文提出一个求解方法，所提出的方法首先将生产线分为两个无重叠的区域，并且为每个区域分配一个抓钩，然后，提出了一个给定抓钩分配下的混合整数线性规划模型。通过求解不同抓钩分配下模型的最优解，并且选择这些解中最好的一个，以便得到最优解，一个标杆示例被运行，以表明该方法的应用。另外，给出有多重处理槽工序问题的模型和求解方法。

英文摘要：

In today＇s highly automatic manufacturing systems, computer-controlled hoists affect directly the productivity of the systems. In this paper, we study the cyclic scheduling problem with electroplating lines where products are loaded into the system at one end and unloaded at the other end. The processing time at each workstation must be within a given range. There is no buffer between these stations. Two hoists sharing a common track are used to move products between the workstations in the line. The objective is to schedule the moves to minimize the production cycle. To solve the problem, we propose a method, with which we first divide the line into two non-overlapping zones and assign a hoist for each zone. Then a mixed integer linear programming model is developed for given hoist assignment. Solving the model at different hoist assignment and comparing with these different solutions we get the optimal solution. An example is given to demonstrate the application of the proposed method. Besides, both a model and a solving method are given for multi-tank.