Integrated Studies On Job Shop Processing And Shipment Planning

In supply chain management, there are lots of material and product flows with different features and different directions. Assembly parts could be manufactured at different factories, and shipped to the assembly factory for processing. Finished products are then shipped to the retailers or customers by logistics companies. In this study, a job is defined as a sequence of manufacturing activities and logistics activities. A manufacturing activity performs some specific engineering tasks in the production process. Logistics activities generally refer to the physical movement of materials and products and warehousing in the shipping process. In practice, decision makers often manage a portfolio of jobs or product lines in the company. The arrangement of manufacturing activities is considered in "job shop processing". The objective is to determine the machine assignment to complete job activities. On the shipping process, the management of logistics activities is studied in "shipment planning". Nowadays, a manufacturing job may be processed at several locations. The research of job shop processing and shipment planning should be integrated. Extensive works are found in the study of job shop scheduling and shipment planning respectively. However, the existing studies mostly ignore the linkages between job shop processing and shipment planning. This thesis develops several models to study the integration of job shop processing and shipment planning. Managerial issues that affect the job processing cost are addressed.The first study considers a shipment planning problem which includes both forward and reverse logistics jobs and the identification of reverse logistics centers. The inclusion of reverse logistics jobs introduce manufacturing process activities and transport activities in different directions. In this study, the cost saving factors through combining forward and reverse logistics activities are considered in managing the job portfolio. The site selection of reverse logistics centers focuses on the cost saving in the grouping of job processing activities at the same location. Results show that the reduction in total job processing cost could be achieved from the compatibility and integration among forward and reverse logistics jobs.The second study studies a job shop processing problem where the processing activity locations are to be determined. We consider a job shop processing problem where the machines could be set up in several factories at different locations. Thus, the shipping of materials and parts in job processing is a consideration in cost saving. The objective of this problem is determining the machine set up locations and the machine assignment of job activities in minimizing the total job processing cost. A NLP model is proposed to solve this job shop problem and managerial issues are discussed.This thesis contributes to the integration study of job shop processing and shipment planning. The research provides useful tools for practitioners in supply chain management who manage several product lines that include both job processing and shipment activities.