A survey of scheduling problems with setup times or costs

Author name used in this publication: C. T. NgAuthor name used in this publication: T. C. E. Cheng2007-2008 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Analysis of a Parallel Machine Scheduling Problem with Sequence Dependent Setup Times and Job Availability Intervals

In this study, we propose constraint programming (CP) model and logic-based Benders algorithms in order to make the best decisions for scheduling non-identical jobs with availability intervals and sequence dependent setup times on unrelated parallel machines in a fixed planning horizon. In this problem, each job has a profit, cost and must be assigned to at most one machine in such a way that total profit is maximized. In addition, the total cost has to be less than or equal to a budget level. Computational tests are performed on a real-life case study prepared in collaboration with the U.S. Army Corps of Engineers (USACE). Our initial investigations show that the pure CP model is very efficient in obtaining good quality feasible solutions but, fails to report the optimal solution for the majority of the problem instances. On the other hand, the two logic-based Benders decomposition algorithms are able to obtain near optimal solutions for 86 instances out of 90 examinees. For the remaining instances, they provide a feasible solution. Further investigations show the high quality of the solutions obtained by the pure CP model

Integrated machine-scheduling and inventory planning of door manufacturing operations at OYAK Renault factory

Ankara : The Department of Industrial Engineering and the Graduate School of Engineering and Science of Bilkent University, 2012.Thesis (Master's) -- Bilkent University, 2012.Includes bibliographical references.A car passes through press, body shell, painting and assembly stages during its manufacturing process. Due to the increased competition among car manufacturers, they aim to continuously advance and improve their processes. In this study, we analyze planning operations for the production of front/back and left/right doors in body shell department of Bursa Oyak-Renault factory and propose heuristic algorithms to improve their planning processes. In this study, we present four different mathematical models and two heuristics approaches which decrease the current costs of the company particularly with respect to inventory carrying and setup perspectives. In the body shell department of the company, there are two parallel manufacturing cells which produces doors to be assembled on the consumption line. The effective planning and scheduling of the jobs on these lines requires solving the problem of integrated machine-scheduling and inventory planning subject to inclusive eligibility constraints and sequence independent setup times with job availability in flexible manufacturing cells of the body shell department. The novelty in the models lie in the integration of inventory planning and production scheduling decisions with the aim of streamlining operations of the door manufacturing cells with the consumption line. One of the proposed heuristic approaches is Rolling Horizon Algorithm (RHA) which divides the planning horizon into sub-intervals and solves the problem by rolling the solutions through sub-intervals. The other proposed algorithm is Two-Pass Algorithm which divides the planning horizon into sub-intervals and solves each sub-problem in each sub-interval to optimality for two times by maintaining the starting and ending inventory levels feasible. These approaches are implemented with Gurobi optimization software and Java programming language and applied within a decision support system that supports daily planning activities.Bozkaya, NurcanM.S

Theoretical and Computational Research in Various Scheduling Models

Nine manuscripts were published in this Special Issue on “Theoretical and Computational Research in Various Scheduling Models, 2021” of the MDPI Mathematics journal, covering a wide range of topics connected to the theory and applications of various scheduling models and their extensions/generalizations. These topics include a road network maintenance project, cost reduction of the subcontracted resources, a variant of the relocation problem, a network of activities with generally distributed durations through a Markov chain, idea on how to improve the return loading rate problem by integrating the sub-tour reversal approach with the method of the theory of constraints, an extended solution method for optimizing the bi-objective no-idle permutation flowshop scheduling problem, the burn-in (B/I) procedure, the Pareto-scheduling problem with two competing agents, and three preemptive Pareto-scheduling problems with two competing agents, among others. We hope that the book will be of interest to those working in the area of various scheduling problems and provide a bridge to facilitate the interaction between researchers and practitioners in scheduling questions. Although discrete mathematics is a common method to solve scheduling problems, the further development of this method is limited due to the lack of general principles, which poses a major challenge in this research field