Seeking Simulation-based Optimization of Job shop Scheduling in Small and Medium Enterprises to Minimize the Cost of Tardiness and Earliness of Activities

• Main Authors: Seyed Mojtaba Sajadi, Sadegh Shahbazi
• Format: Article
• Language: fas
• Published: University of Tehran 2017-04-01
• Series: مدیریت صنعتی
• Subjects: Cost of tardiness and earliness; Job shop; Optimization; Queue; simulation
• Online Access: https://imj.ut.ac.ir/article_63902_8aa8bf202c281703773ebd14a5011e53.pdf
• ISSN: 2008-5885; 2423-5369

Determining the optimal sequence of jobs in job shop scheduling for small and medium enterprises, affect the machine productivity, earliness and tardiness costs of delivery. The deterministic variant of the problem is well-known to be NP-Hard. If random elements are introduced into the problem, the level of complexity goes higher. Hence, many priority rules have been developed to tackle stochastic job shop scheduling problem. However, to devise a better solution approach, simulation-optimization approach might be used. In this study, a mathematical model was developed for job shop scheduling with random process times and possible machine breakdowns. Then, a simulation-optimization model was applied to choose among a list of priority rules using Rockwell Arena 14. Finally, a numerical example was used to evaluate the quality of the model. Results showed that the rule Longest Processing Time (LPT) yields the lowest total earliness and tardiness costs. However, the total costs of the following rules are also acceptable: First in First out (FIFO), Last in First out (LIFO), Earliest Due Date (EDD) and Slack time (Slack).