Production and Manpower Scheduling

调度的一般描述是随时间分配资源以执行一组任务。在文献中，这种解决调度问题的关键方法被形式化为调度理论。然而，在实践中，不同公司之间的调度差异很大，没有“现实世界”调度的确定模型可以帮助制造业。研究界缺乏对调度现实的关注，导致了理论与实践之间的所谓“差距”。许多研究人员只是乐观地认为，他们新的和改进的启发式方法将通过调度软件供应商嵌入到计算机系统中，然后在作业车间广泛使用。然而，大多数作坊式的工厂仍在使用一套远非最佳的调度规则，以老式的方式进行调度和计划。很明显，开发调度算法的理论研究对改进调度实践几乎没有什么帮助。这导致许多行业没有非常适合他们需求的调度系统。在合作行业中确定的研究问题涉及到制造工厂冲压区域大量订单的调度问题。复杂性来自于制造操作及其需求的许多相互依赖关系。所要开发的调度框架和解决方法是将传统调度理论中的作业调度规则与离散事件系统仿真理论中的事件调度/时间提前算法（ESTA）相结合的混合方法。作业调度规则使用简单。然而，它们缺乏处理复杂操作逻辑的能力，也不提供时间表。为了利用这些简单的调度规则获得实际的生产调度，本研究将采用离散事件仿真的概念。这样，制造系统的操作逻辑将在计算机程序中建模。然后使用离散事件系统仿真的ESTA算法在模拟时间内执行调度规则以生成生产计划。

A general description of scheduling is the allocation of resources over time to perform a collection of tasks. Inliterature, this critical approach to scheduling problems has been formalized as scheduling theory. Schedulingin practice, however, varies greatly between different companies with no definitive model of "real world"scheduling available to aid manufacturing industries. The lack of attention to the realities of scheduling by theresearch community has given the rise to the so-called ''gap" between theory and practice. Many researcherswere simply optimistic that their new and improved heuristics would be embedded in a computer systems byscheduling software vendors, which would then in turn be widely used in job shops. However, most job shopstyle factories are still scheduling and planning the old-fashioned way using a collection of dispatching rulesthat are far from being optimal. It is apparent that theoretical research in developing algorithms for schedulinghas done little to improve the scheduling practice. This has resulted in many industries not having schedulingsystems very tailored to their needs. The research problem identified in the collaborating industry involves thescheduling of large numbers of orders in the stamping area of the manufacturing plant. Complexity arises fromthe many inter-dependencies of the manufacturing operations and their requirements. The schedulingframework and the solution methodology to be develop is a hybrid approach that combines Job-Dispatchingrules from traditional scheduling theory and Event-Scheduling/Time-Advance algorithm (ESTA) from thetheory of discrete event systems simulation. Job-dispatching rule are simple to use. However, they lack theability to handle complex operational logic and do not provide schedule. To obtain actual production scheduleusing these simple dispatching rules, in this research, we will apply the concept of discrete event simulation. Indoing so, the operational logic of the manufacturing systems will be modeled in a computer program. Thedispatching rules will then be executed in a simulated time using ESTA algorithm of discrete event systemssimulation to generate production schedules.