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The short-term scheduling problem (STSP) of oil refinery operations with unreliable distillation units (CDUs) is a NPhard problem, necessitating a high degree of accuracy and efficient techniques. Developing effective scheduling optimization techniques for oil refineries is a significant challenge. In order to provide solutions to this difficult problem, this study proposes a new hybrid Petri net and tabu search (PNTS) approach with unreliable CDUs to effectively solve this problem. To show the efficiency of the developed approach, an industrial case study is used. The results demonstrate that the developed method efficiently solves the industrial case study. [ABSTRACT FROM AUTHOR]

Machines can become unavailable during the planning horizon due to unexpected breakdowns. Such periods of unavailability should be properly taken into account when designing the production schedule. This paper proposes an optimal solution to unrelated parallel machine scheduling problems with availability constraints based on timed Petri nets (TPNs) to minimize the maximum completion time of jobs. For this NP-hard problem, a new hybrid Petri net and tabu search (PNTS) approach is proposed to find an optimal solution for this problem. A numerical example is used to assess the performance of the proposed PNTS. The computational results highlight the ability of the proposed PNTS to obtain optimal solutions for this problem. [ABSTRACT FROM AUTHOR]

Deadlock control techniques for automated systems have been developed based on Petri nets. Some resources in these systems are unreliable or failing. Thus, the developed deadlock policies are not appropriate to these systems. Thus, this paper presents a strategy for solving deadlocks in systems with unreliable resources. The first step is to apply elementary siphon control method to design control places without considering resources failures. Second, all control places in the first step are merged into a global control place by using a colored Petri net. The third stage involves the design of a common recovery subnet based on colored Petri nets to handle all resource failures. Finally, the proposed strategy is evaluated using a manufacturing system from the literature. The results demonstrate that the suggested strategy is capable of handling all unreliable resources in the system, has a simpler structure, and has small computational overhead. [ABSTRACT FROM AUTHOR]

Petri nets are an effective way to model, analyze, and control deadlocks in automated manufacturing systems (AMSs). The need for an effective design tool to design a control system and convert Petri net to ladder diagram for PLC implementation becomes increasingly more important. Therefore, the objective of this paper is to design behaviorally optimal liveness-enforcing supervisor for automated manufacturing system and their ladder diagram for programmable logic controller (PLC) implementation. To do this, first, deadlock prevention method (elementary siphons control method) has been used to design a supervisor to prevent the deadlock in AMSs. Next, a token passing logic (TPL) technique has used to convert the resulted controlled model into ladder diagrams (LDs) for implementation. Finally, the presented methodology can be applied for multiproduct and sizes of AMSs and provided a more effective for PLC implementation. [ABSTRACT FROM AUTHOR]

Bibliometric analysis is a statistical tool that can quantitatively measure and assess the research impact of a subject of interest. It focuses on identifying research strengths and weaknesses, assessing country contributions, and recognizing the impact of journals and top authors. Recently, a bibliometric analysis was applied to characterize the author's affiliation, citation habits, and research collaborations. Petri net tool is evolving rapidly and gaining popularity in the research community. This paper displays a public picture of research in Petri nets in manufacturing systems sciences by utilizing and analyzing indicators of bibliometric analysis. The main objective is that these indicators present a public review, determining the most effective and influential research around this field. The analysis of the study is partitioned into key areas that related to journals, papers, keywords, authors, and nations or countries. Moreover, the study aims to be informative and identifying most researches in this field. However, some very influential issues may omit if they are not included in the Web of Science database. The outcomes of the study give a clear roadmap for research in this field in future. [ABSTRACT FROM AUTHOR]

Quality is becoming a business strategy leading to success, growth, and enhanced competitive position. Organizations with successful quality improvement programs can enjoy significant competitive advantages. With increasing automation and mechanization, production processes are shifting from workers to machines. Consequently, the role of equipment maintenance in controlling quantity, quality and costs are more evident and important than ever. To succeed in this new environment, equipment must be maintained in ideal operating conditions and must run effectively. This paper summarizes an overview of integrating statistical process control and maintenance by jointly optimizing their policies to minimize the total costs associated with quality, maintenance, and inspection. Based on the review of some typical new approaches and methods that were introduced, the advantages and disadvantages of these methodologies were discussed. Finally, a review of the literature, there has been some increased trends in the area of integrated research on maintenance and quality control. [ABSTRACT FROM AUTHOR]