On sequencing ordered matrix flowshop problems

Abstract

In industrial processes, several jobs are processed by the same set of machines or facilities. As a result, each job competes for the use of the available facilities. The problem is then to determine the sequence in which the jobs should be processed at each facility in order to satisfy some objective criterion.

Sequencing problems can be divided into three broad categories; flowshop, job shop, and general sequencing. These categories are based on the job routing patterns in a shop. Within the flowshop category Smith [11] has defined subcategories, two of which are called "ordered matrix" and "semiordered matrix problem".

This research is concerned with the ordered matrix problem. The purpose of the research is to analyze the problem with respect to three different objective criteria. These objective criteria are the minimum makespan, minimum mean completion time of jobs and minimum total tardiness of late jobs. The relevance and importance of these criteria will be discussed in subsequent chapters.