In this paper, we deal with the problem of a joint maintenance and production policy under a subc... more In this paper, we deal with the problem of a joint maintenance and production policy under a subcontracting constraint. In fact, this paper is the continuity of our previous work. The manufacturing system under consideration consists of a machine M that produces a single product. To satisfy a random demand d under a given service level constraint, the system called upon another machine M 2 (the subcontractor) which recycles and remanufactures the products rejected by the customer. We first establish an optimal production plan which minimizes the total inventory and production cost taking into consideration the subcontractor constraint. Secondly, using this optimal production plan and based on the operational age concept, we derive an optimal maintenance schedule which minimizes the total maintenance cost. Finally, a numerical example is studied in order to apply the developed approach.
After the results from a research project with former students of the university were published i... more After the results from a research project with former students of the university were published in Applied Sciences [...]
This paper proposes an optimal solution to large-scale Flexible Manufacturing System (FMS) schedu... more This paper proposes an optimal solution to large-scale Flexible Manufacturing System (FMS) scheduling problems under availability constraints based on Timed Petri Nets (TPNs). First a decomposition method of TPNs is proposed, then a mathematical model is derived based on their properties. The mathematical model is built to determine the optimal firing sequence of TPN transitions to minimize the total manufacturing time. The resulting firing sequence of TPN transitions is used to generate the manufacturing system supervisor operated by TPN and digital controllers. Several numerical examples and comparative studies are provided in this paper in order to prove the new approach's efficiency.
Ym ci _ nXllZfo p qrstu Wfv]g w_ xZg y dZoz g Zi {Xx]Y Zo l_ o_ lXi dfz x XoY |]z g _ o]z xf{m dZ... more Ym ci _ nXllZfo p qrstu Wfv]g w_ xZg y dZoz g Zi {Xx]Y Zo l_ o_ lXi dfz x XoY |]z g _ o]z xf{m dZoz g Zi i ]g x dZZg Y_ oXz _ Zoa } oz ]g oXz _ ZoXĩ Zfg oXi Z Wyxz ]lx Wd_ ]od]a sa qm a } sr srr rrqrqs qrs srtr U() ' "L # (# C' 0 &%# ' 2) $4
Journal of Quality in Maintenance Engineering, 2015
Purpose – The purpose of this paper is to determine a nearly optimal inspection sequence for a se... more Purpose – The purpose of this paper is to determine a nearly optimal inspection sequence for a series system consisting of two components subject to gradual deterioration and whose failures are not self-announcing and can be detected only through inspection. Design/methodology/approach – The problem is tackled in the context of condition-based maintenance (CBM) with a maintenance model in the class of the control-limit policies for which the maintenance decision is made following inspection by comparison of the deterioration level to critical thresholds. A mathematical model is developed to express the total expected cost per time unit as a function of the inspection instants. Findings – For any given series system composed of two components with known critical deterioration threshold levels, and for any given set of costs related to inspection, inactivity due to failure, and preventive and corrective replacements of each component, a nearly optimal inspection sequence of the system...
This paper addresses the design of Petri net (PN) supervisor using the theory of regions for forb... more This paper addresses the design of Petri net (PN) supervisor using the theory of regions for forbidden state problem with a set of general mutual exclusion constraints. In fact, as any method of supervisory control based on reachability graph, the theory of regions suffers from a technical obstacle in control synthesis, which is the necessity of computing the graph at each iteration step. Moreover, based on the reachability graph, which may contain a large number of states, with respect to the structural size of the system, the computation of PN controllers becomes harder and even impossible. The main contribution of this paper, compared to previous works, is the development of a control synthesis method in order to decrease significantly the computation cost of the PN supervisor. Thus, based on PN properties and mathematical concepts, the proposed methodology provides an optimal PN supervisor for bounded Petri nets following the interpretation of the theory of regions. Finally, case studies are solved by CPLEX software to compare our new control policy with previous works which use the theory of regions for control synthesis.
2008 IEEE International Conference on Industrial Engineering and Engineering Management, 2008
Abstract - In this paper, we have developed an integrated maintenance policy for a manufacturing ... more Abstract - In this paper, we have developed an integrated maintenance policy for a manufacturing system subjected to a random failure and calling up on several subcontractor machines. The problem consists on a machine, unable to satisfy a constant demand. That's why it called ...
A data mining approach is integrated in this work for predictive sequential maintenance along wit... more A data mining approach is integrated in this work for predictive sequential maintenance along with information on spare parts based on the history of the maintenance data. For most practical problems, the simple failure of one part of a given piece of equipment induces the subsequent failure of the other parts of said equipment. For example, it is frequently observed in mining industries that, like many other industries, the maintenance of conventional equipment is carried out in sequence. Besides, depending on the state of parts of the equipment, many parts can be consumed and replaced. Consequently, with a group of spare parts consumed sequentially in various maintenance activities, it is possible to discover sequential maintenance activities. From maintenance data with predefined support or threshold values and spare parts information, this work determines the sequential patterns of maintenance activities. The proposed method predicts the occurrence of the next maintenance activi...
Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA), 2014
This paper deals with the production control of a manufacturing/remanufacturing system within a c... more This paper deals with the production control of a manufacturing/remanufacturing system within a closed loop reverse logistics system with machines subject to random failures and repairs. Three types of inventories are involved in this system. The manufactured and remanufactured products are stored respectively in the manufacturing and remanufacturing inventories. The returned products are collected in the recovery inventory and then remanufactured. The customer demands are constant and known. To describe the system, a stochastic fluid model is adopted and which take into account returned products and remanufacturing products. The objective of this paper is to evaluate the optimal inventory levels of the manufacturing and remanufacturing products that allow minimizing the total cost which is the sum of inventory and lost sales costs. Infinitesimal perturbation analysis is used for optimization of the considered system. The trajectories of the inventories levels are studied and the infinitesimal perturbation analysis estimates are evaluated. These estimates are shown to be unbiased and then they are implemented in an optimization algorithm which determines the optimal inventories levels.
In this paper, we deal with the problem of maintenance planning and production planning for a mul... more In this paper, we deal with the problem of maintenance planning and production planning for a multiple-product manufacturing system. The manufacturing system under consideration consists of one machine which is subject to random failures and produces several products in order to satisfy some random demands. At any given time, the machine can only produce one type of product. The purpose of this study is to establish an economical production planning followed by an optimal maintenance strategy, taking into account the influence of production rate on the system degradation. Analytical models are developed in order to minimize sequentially the production/storage costs and the total maintenance cost. Finally, a numerical example is presented to illustrate the usefulness of the proposed approach.
Proceedings of the 11th IEEE International Conference on Networking, Sensing and Control, 2014
In this paper, a stochastic fluid model is used to study a manufacturing/ remanufacturing system ... more In this paper, a stochastic fluid model is used to study a manufacturing/ remanufacturing system composed by two parallel machines, a serviceable inventory, a remanufacturing inventory and customers who demand a stochastic quantity of product. Stochastic fluid model is adopted to describe the system and to take into account machine failure, stochastic demand, stochastic returned products and remanufacturing products. The goal of this paper is to evaluate the optimal serviceable inventory level which allows minimizing the sum of inventory and lost sales costs. Perturbation analysis is applied to the stochastic fluid model to optimize the considered system. The trajectories of the serviceable inventory level are studied and the perturbation analysis estimates are evaluated. The unbiasedness of these estimates is proved and then they are implemented in an optimization algorithm which determines the optimal serviceable inventory in the presence of stochastic returned products and stochastic demand.
Sixth International Workshop on Discrete Event Systems, 2002. Proceedings., 2002
This paper presents a formal treatment of Petri net controller design problems. Two supervisory c... more This paper presents a formal treatment of Petri net controller design problems. Two supervisory control problems of plant Petri net models, forbidden state and forbidden state-transition problems, are defined. The theory of regions is used to provide algebraic ...
2001 IEEE International Conference on Systems, Man and Cybernetics. e-Systems and e-Man for Cybernetics in Cyberspace (Cat.No.01CH37236), 2001
Abstract The job shop scheduling problem (JSP) deals with the sequencing operations of a set of j... more Abstract The job shop scheduling problem (JSP) deals with the sequencing operations of a set of jobs on a set of machines with minimum cost. The flexible job shop scheduling problem (FJSP) is a generalization of the JSP, which is concerned with both the ...
Proceedings 2002 IEEE International Conference on Robotics and Automation (Cat. No.02CH37292), 2002
Forbidden state problem of Petri nets with non blocking requirement and uncontrollable transition... more Forbidden state problem of Petri nets with non blocking requirement and uncontrollable transitions is addressed in this paper. The approach proposed in this paper combines the Ramadge-Wonham's approach and the theory of regions, a theory recently proposed for compiling a labelled automaton into a Petri net. It first determines the automaton model of the closed loop system using a Ramadge-Wonham-like approach. It then uses the theory of regions to design a set of control places to add to the initial Petri net to realize the maximum permissive and non blocking control. Although the proposed approach does not avoid the state explosion problem in its design phase, it does provide a compact representation of the optimum control in terms of control places and hence can be very useful in the implementation of optimum control. 1895 0-7803-7272-7/02/$17.00
2008 IEEE International Conference on Industrial Engineering and Engineering Management, 2008
In this paper, we have developed an integrated maintenance policy for a manufacturing system subj... more In this paper, we have developed an integrated maintenance policy for a manufacturing system subjected to a random failure and calling up on several subcontractor machines in order to satisfy a constant demand. In order to reduce the machine failure a preventive maintenance plan is made. The machine is unable to satisfy a constant demand, that's why it called upon another machine, comprising the so-called subcontractor machine, which produces at a certain rate the same type of product. In order to assure an economical objective, we have a choice between several subcontractors having some different data and to optimize the preventive maintenance plan. Two strategies are developed and optimized in this work. The first strategy, single subcontractor strategy, consists in choosing only one subcontractor among several ones. For this strategy we have proved analytically, that the choice of the subcontractor machines is conditioned by the unit lost cost due an unsatisfied demand of one product; The second strategy, switching strategy, consists in relaying on one subcontractor machine and then switching to another. An analytical study is developed in order to optimize firstly the preventive maintenance plan and secondly to determine the optimal switching date. A numerical example is developed for very strategy in order to apply the analytical results.
2008 IEEE International Conference on Industrial Engineering and Engineering Management, 2008
Abstract Several periodic preventive maintenance (PM) models have been developed in the literatur... more Abstract Several periodic preventive maintenance (PM) models have been developed in the literature. This paper introduces an adaptive failure law which can vary over time depending on the missions to achieve. From this degradation law, the purpose of this paper is to ...
In this paper, we deal with the problem of a joint maintenance and production policy under a subc... more In this paper, we deal with the problem of a joint maintenance and production policy under a subcontracting constraint. In fact, this paper is the continuity of our previous work. The manufacturing system under consideration consists of a machine M that produces a single product. To satisfy a random demand d under a given service level constraint, the system called upon another machine M 2 (the subcontractor) which recycles and remanufactures the products rejected by the customer. We first establish an optimal production plan which minimizes the total inventory and production cost taking into consideration the subcontractor constraint. Secondly, using this optimal production plan and based on the operational age concept, we derive an optimal maintenance schedule which minimizes the total maintenance cost. Finally, a numerical example is studied in order to apply the developed approach.
After the results from a research project with former students of the university were published i... more After the results from a research project with former students of the university were published in Applied Sciences [...]
This paper proposes an optimal solution to large-scale Flexible Manufacturing System (FMS) schedu... more This paper proposes an optimal solution to large-scale Flexible Manufacturing System (FMS) scheduling problems under availability constraints based on Timed Petri Nets (TPNs). First a decomposition method of TPNs is proposed, then a mathematical model is derived based on their properties. The mathematical model is built to determine the optimal firing sequence of TPN transitions to minimize the total manufacturing time. The resulting firing sequence of TPN transitions is used to generate the manufacturing system supervisor operated by TPN and digital controllers. Several numerical examples and comparative studies are provided in this paper in order to prove the new approach's efficiency.
Ym ci _ nXllZfo p qrstu Wfv]g w_ xZg y dZoz g Zi {Xx]Y Zo l_ o_ lXi dfz x XoY |]z g _ o]z xf{m dZ... more Ym ci _ nXllZfo p qrstu Wfv]g w_ xZg y dZoz g Zi {Xx]Y Zo l_ o_ lXi dfz x XoY |]z g _ o]z xf{m dZoz g Zi i ]g x dZZg Y_ oXz _ Zoa } oz ]g oXz _ ZoXĩ Zfg oXi Z Wyxz ]lx Wd_ ]od]a sa qm a } sr srr rrqrqs qrs srtr U() ' "L # (# C' 0 &%# ' 2) $4
Journal of Quality in Maintenance Engineering, 2015
Purpose – The purpose of this paper is to determine a nearly optimal inspection sequence for a se... more Purpose – The purpose of this paper is to determine a nearly optimal inspection sequence for a series system consisting of two components subject to gradual deterioration and whose failures are not self-announcing and can be detected only through inspection. Design/methodology/approach – The problem is tackled in the context of condition-based maintenance (CBM) with a maintenance model in the class of the control-limit policies for which the maintenance decision is made following inspection by comparison of the deterioration level to critical thresholds. A mathematical model is developed to express the total expected cost per time unit as a function of the inspection instants. Findings – For any given series system composed of two components with known critical deterioration threshold levels, and for any given set of costs related to inspection, inactivity due to failure, and preventive and corrective replacements of each component, a nearly optimal inspection sequence of the system...
This paper addresses the design of Petri net (PN) supervisor using the theory of regions for forb... more This paper addresses the design of Petri net (PN) supervisor using the theory of regions for forbidden state problem with a set of general mutual exclusion constraints. In fact, as any method of supervisory control based on reachability graph, the theory of regions suffers from a technical obstacle in control synthesis, which is the necessity of computing the graph at each iteration step. Moreover, based on the reachability graph, which may contain a large number of states, with respect to the structural size of the system, the computation of PN controllers becomes harder and even impossible. The main contribution of this paper, compared to previous works, is the development of a control synthesis method in order to decrease significantly the computation cost of the PN supervisor. Thus, based on PN properties and mathematical concepts, the proposed methodology provides an optimal PN supervisor for bounded Petri nets following the interpretation of the theory of regions. Finally, case studies are solved by CPLEX software to compare our new control policy with previous works which use the theory of regions for control synthesis.
2008 IEEE International Conference on Industrial Engineering and Engineering Management, 2008
Abstract - In this paper, we have developed an integrated maintenance policy for a manufacturing ... more Abstract - In this paper, we have developed an integrated maintenance policy for a manufacturing system subjected to a random failure and calling up on several subcontractor machines. The problem consists on a machine, unable to satisfy a constant demand. That's why it called ...
A data mining approach is integrated in this work for predictive sequential maintenance along wit... more A data mining approach is integrated in this work for predictive sequential maintenance along with information on spare parts based on the history of the maintenance data. For most practical problems, the simple failure of one part of a given piece of equipment induces the subsequent failure of the other parts of said equipment. For example, it is frequently observed in mining industries that, like many other industries, the maintenance of conventional equipment is carried out in sequence. Besides, depending on the state of parts of the equipment, many parts can be consumed and replaced. Consequently, with a group of spare parts consumed sequentially in various maintenance activities, it is possible to discover sequential maintenance activities. From maintenance data with predefined support or threshold values and spare parts information, this work determines the sequential patterns of maintenance activities. The proposed method predicts the occurrence of the next maintenance activi...
Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA), 2014
This paper deals with the production control of a manufacturing/remanufacturing system within a c... more This paper deals with the production control of a manufacturing/remanufacturing system within a closed loop reverse logistics system with machines subject to random failures and repairs. Three types of inventories are involved in this system. The manufactured and remanufactured products are stored respectively in the manufacturing and remanufacturing inventories. The returned products are collected in the recovery inventory and then remanufactured. The customer demands are constant and known. To describe the system, a stochastic fluid model is adopted and which take into account returned products and remanufacturing products. The objective of this paper is to evaluate the optimal inventory levels of the manufacturing and remanufacturing products that allow minimizing the total cost which is the sum of inventory and lost sales costs. Infinitesimal perturbation analysis is used for optimization of the considered system. The trajectories of the inventories levels are studied and the infinitesimal perturbation analysis estimates are evaluated. These estimates are shown to be unbiased and then they are implemented in an optimization algorithm which determines the optimal inventories levels.
In this paper, we deal with the problem of maintenance planning and production planning for a mul... more In this paper, we deal with the problem of maintenance planning and production planning for a multiple-product manufacturing system. The manufacturing system under consideration consists of one machine which is subject to random failures and produces several products in order to satisfy some random demands. At any given time, the machine can only produce one type of product. The purpose of this study is to establish an economical production planning followed by an optimal maintenance strategy, taking into account the influence of production rate on the system degradation. Analytical models are developed in order to minimize sequentially the production/storage costs and the total maintenance cost. Finally, a numerical example is presented to illustrate the usefulness of the proposed approach.
Proceedings of the 11th IEEE International Conference on Networking, Sensing and Control, 2014
In this paper, a stochastic fluid model is used to study a manufacturing/ remanufacturing system ... more In this paper, a stochastic fluid model is used to study a manufacturing/ remanufacturing system composed by two parallel machines, a serviceable inventory, a remanufacturing inventory and customers who demand a stochastic quantity of product. Stochastic fluid model is adopted to describe the system and to take into account machine failure, stochastic demand, stochastic returned products and remanufacturing products. The goal of this paper is to evaluate the optimal serviceable inventory level which allows minimizing the sum of inventory and lost sales costs. Perturbation analysis is applied to the stochastic fluid model to optimize the considered system. The trajectories of the serviceable inventory level are studied and the perturbation analysis estimates are evaluated. The unbiasedness of these estimates is proved and then they are implemented in an optimization algorithm which determines the optimal serviceable inventory in the presence of stochastic returned products and stochastic demand.
Sixth International Workshop on Discrete Event Systems, 2002. Proceedings., 2002
This paper presents a formal treatment of Petri net controller design problems. Two supervisory c... more This paper presents a formal treatment of Petri net controller design problems. Two supervisory control problems of plant Petri net models, forbidden state and forbidden state-transition problems, are defined. The theory of regions is used to provide algebraic ...
2001 IEEE International Conference on Systems, Man and Cybernetics. e-Systems and e-Man for Cybernetics in Cyberspace (Cat.No.01CH37236), 2001
Abstract The job shop scheduling problem (JSP) deals with the sequencing operations of a set of j... more Abstract The job shop scheduling problem (JSP) deals with the sequencing operations of a set of jobs on a set of machines with minimum cost. The flexible job shop scheduling problem (FJSP) is a generalization of the JSP, which is concerned with both the ...
Proceedings 2002 IEEE International Conference on Robotics and Automation (Cat. No.02CH37292), 2002
Forbidden state problem of Petri nets with non blocking requirement and uncontrollable transition... more Forbidden state problem of Petri nets with non blocking requirement and uncontrollable transitions is addressed in this paper. The approach proposed in this paper combines the Ramadge-Wonham's approach and the theory of regions, a theory recently proposed for compiling a labelled automaton into a Petri net. It first determines the automaton model of the closed loop system using a Ramadge-Wonham-like approach. It then uses the theory of regions to design a set of control places to add to the initial Petri net to realize the maximum permissive and non blocking control. Although the proposed approach does not avoid the state explosion problem in its design phase, it does provide a compact representation of the optimum control in terms of control places and hence can be very useful in the implementation of optimum control. 1895 0-7803-7272-7/02/$17.00
2008 IEEE International Conference on Industrial Engineering and Engineering Management, 2008
In this paper, we have developed an integrated maintenance policy for a manufacturing system subj... more In this paper, we have developed an integrated maintenance policy for a manufacturing system subjected to a random failure and calling up on several subcontractor machines in order to satisfy a constant demand. In order to reduce the machine failure a preventive maintenance plan is made. The machine is unable to satisfy a constant demand, that's why it called upon another machine, comprising the so-called subcontractor machine, which produces at a certain rate the same type of product. In order to assure an economical objective, we have a choice between several subcontractors having some different data and to optimize the preventive maintenance plan. Two strategies are developed and optimized in this work. The first strategy, single subcontractor strategy, consists in choosing only one subcontractor among several ones. For this strategy we have proved analytically, that the choice of the subcontractor machines is conditioned by the unit lost cost due an unsatisfied demand of one product; The second strategy, switching strategy, consists in relaying on one subcontractor machine and then switching to another. An analytical study is developed in order to optimize firstly the preventive maintenance plan and secondly to determine the optimal switching date. A numerical example is developed for very strategy in order to apply the analytical results.
2008 IEEE International Conference on Industrial Engineering and Engineering Management, 2008
Abstract Several periodic preventive maintenance (PM) models have been developed in the literatur... more Abstract Several periodic preventive maintenance (PM) models have been developed in the literature. This paper introduces an adaptive failure law which can vary over time depending on the missions to achieve. From this degradation law, the purpose of this paper is to ...
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