Integrated Production and Manpower Scheduling - Second Phase

在调度研究中，大多数已发表的文章都集中在开发模型和算法来解决应用有限的理论问题。在合作公司中发现的调度问题恰好与文献中所知的非常不同。它涉及到具有更大操作复杂性的大量订单的调度。产品上的许多操作都是逐个单元地进行的。然而，大多数产品还需要通过批处理设施，这显然很复杂，以便纳入调度模型。此外，产品需要加工和装配操作，其中组件和子组件需要通过许多加工站。有些产品的操作是外包的，它们的半成品库存需要发送到其他设施，并返回进行进一步的内部处理。机器操作员是有限的资源。许多操作员都经过交叉培训，可以被分配到不同类型的机器上。操作员也可以同时操作多台机器。因此，他们的任务需要在操作过程中详细安排。生产设施的关键部分实行多班制或加班制，而其余部分只实行单班制。这些问题特征的独特组合使得调度非常困难。因此，该公司面临的挑战是如何以最小的在制品库存顺利运行其业务，同时满足产品交付日期。初步研究了一种基于事件调度/时间提前（ESTA）算法的高效调度技术。该方法被证明能够处理制造设施的许多操作逻辑，并为机器和操作员生成时间表，并优化几个性能标准。本研究是这一成就的延续，旨在增强开发的算法，以纳入制造系统的几个细节。此外，将进行有限的研究，将生产调度与其他操作问题，如库存管理和维护计划相结合。

Most published articles in scheduling research are focused in developing models and algorithms to theoreticalproblems having limited applications. The scheduling problem identified in the collaborating company happensto be very different from those know in literature. It involves the scheduling of a large variety of orders withgreater operational complexity. Many of the operations on the products are to be processed unit by unit.However, most products also need to passes through a batch processing facility with apparent complexity toincorporate in a scheduling model. Moreover, products need both machining and assembly operations wherecomponents and sub-assemblies need to pass through many processing stations. Some of the products haveoperations that are outsourced and their semi-finished inventory needs to be sent to other facilities and bereturned for further in-house processing. Machine operators are limited resources. Many of these operators arecross trained and can be assigned to different types of machines. Operators may also tend more than onemachine at a time. Hence their task need to be scheduled in details along the operations. Critical segments ofthe manufacturing facility are operated multiple shift or overtime while the rest are operated only a single shift.These unique combination of problem features makes scheduling very difficult. Hence, the company faces achallenge in running its operations smoothly with minimal work-in-process inventory while at the same timemeeting product delivery dates. A preliminary study was conducted to develop an efficient schedulingtechnique based on Event Scheduling/Time Advance (ESTA) algorithm. The approach proves to be capable ofhandling many of the operational logic of the manufacturing facility and generate schedules for the machinesand the operators, and optimize several performance criteria. This research is a continuation of thisachievement and is aimed at enhancing the developed algorithm to incorporate several details of themanufacturing system. Moreover, a limited study will be conducted for integrating production scheduling withother operational issues such as inventory management and maintenance planning.