The Experts below are selected from a list of 235602 Experts worldwide ranked by ideXlab platform
Eric Gouardères - One of the best experts on this subject based on the ideXlab platform.
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Agent Technologies, Infrastructures, Tools, and Applications for E-Services - Multi-agent model to Control Production System: a reactive and emergent approach by cooperation and competition between agents
Lecture Notes in Computer Science, 2003Co-Authors: Mahmoud Tchikou, Eric GouardèresAbstract:Multi-agent Systems have been successfully used in a number of industrial applications. However, in the domain of industrial automation Systems, little practical experience about the use of agents in such a demanding environment exists. Nowadays automation Systems face new challenges and therefore new concepts are needed to meet them. This paper presents a vision of using agents within industrial automation Systems from the point of view of automation engineering. To this end, the characteristic structures of automation Systems are analyzed and opportunities, as well as advantages, of applying agent-oriented concepts are investigated. A possible approach for the integration of a multi-agent System into existing automation Systems is introduced and illustrated by an application example.
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MULTI AGENT MODEL TO Control Production System
2002Co-Authors: Mahmoud Tchikou, Eric GouardèresAbstract:The need of adaptability of Production structures is continuously increased due to decrease of product life cycle and increase of the competition. The efficiency of a Production System is now described not only in term of time cycle, due date, inventory level, but also in term of flexibility and reactivity in order to integrate the evolution of the market. Current methods for real time Control of Production System do not provide sufficient tools for an effective Production activity Control. The origin of such a problem is at the level of existing Control structures. This work details the design of a Production activity Control System based on distributed structure. The structure is based on the distributed artificial intelligence concepts. After having introduced the context and reasoning work, we describe the different parts of our multi-agent model. Lastly, we illustrate this approach on a practical example of Production cell.
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Multi-Agent Model to Control Production System: A Reactive and Emergent Approach by Cooperation and Competition between Agents
2002Co-Authors: Mahmoud Tchikou, Eric GouardèresAbstract:Face to strong competitive market, current companies tend to new methods of Production, switching from a logic of \llprojected planning\gg to a logic of ``Just in time''. In this context, the System that allows Controlling the Production has to be a modular, flexible and reactive System. The hierarchized and classical approaches don't permit any more to take into account the complexity linked to such a System. That's why, we propose an approach, which has reactive, distributive, and emergent properties to Control the System of Production, based on multi-agent System principles. After having introduced the context and reasoning work, we describe the different parts of our multi-agent model. Lastly, we illustrate this approach on a practical example of Production cell.
Mahmoud Tchikou - One of the best experts on this subject based on the ideXlab platform.
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Agent Technologies, Infrastructures, Tools, and Applications for E-Services - Multi-agent model to Control Production System: a reactive and emergent approach by cooperation and competition between agents
Lecture Notes in Computer Science, 2003Co-Authors: Mahmoud Tchikou, Eric GouardèresAbstract:Multi-agent Systems have been successfully used in a number of industrial applications. However, in the domain of industrial automation Systems, little practical experience about the use of agents in such a demanding environment exists. Nowadays automation Systems face new challenges and therefore new concepts are needed to meet them. This paper presents a vision of using agents within industrial automation Systems from the point of view of automation engineering. To this end, the characteristic structures of automation Systems are analyzed and opportunities, as well as advantages, of applying agent-oriented concepts are investigated. A possible approach for the integration of a multi-agent System into existing automation Systems is introduced and illustrated by an application example.
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MULTI AGENT MODEL TO Control Production System
2002Co-Authors: Mahmoud Tchikou, Eric GouardèresAbstract:The need of adaptability of Production structures is continuously increased due to decrease of product life cycle and increase of the competition. The efficiency of a Production System is now described not only in term of time cycle, due date, inventory level, but also in term of flexibility and reactivity in order to integrate the evolution of the market. Current methods for real time Control of Production System do not provide sufficient tools for an effective Production activity Control. The origin of such a problem is at the level of existing Control structures. This work details the design of a Production activity Control System based on distributed structure. The structure is based on the distributed artificial intelligence concepts. After having introduced the context and reasoning work, we describe the different parts of our multi-agent model. Lastly, we illustrate this approach on a practical example of Production cell.
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Multi-Agent Model to Control Production System: A Reactive and Emergent Approach by Cooperation and Competition between Agents
2002Co-Authors: Mahmoud Tchikou, Eric GouardèresAbstract:Face to strong competitive market, current companies tend to new methods of Production, switching from a logic of \llprojected planning\gg to a logic of ``Just in time''. In this context, the System that allows Controlling the Production has to be a modular, flexible and reactive System. The hierarchized and classical approaches don't permit any more to take into account the complexity linked to such a System. That's why, we propose an approach, which has reactive, distributive, and emergent properties to Control the System of Production, based on multi-agent System principles. After having introduced the context and reasoning work, we describe the different parts of our multi-agent model. Lastly, we illustrate this approach on a practical example of Production cell.
Michael Todinov - One of the best experts on this subject based on the ideXlab platform.
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Risk-Based Reliability Analysis and Generic Principles for Risk Reduction - 8 – RELIABILITY VALUE ANALYSIS FOR COMPLEX SystemS
Risk-Based Reliability Analysis and Generic Principles for Risk Reduction, 2007Co-Authors: Michael TodinovAbstract:The purpose of the reliability value analysis is to determine the net present values (NPV) for the two competing Systems and by comparing them, to establish which Production System is more beneficial. In order to reveal the NPV of competing design solutions, discounted cash-flow models have been proposed. The correct estimation of the losses from failures is at the heart of the correct determination of the outflow. The problem with the classical NPV models related to their application for reliability value analysis is that they are based on the expected values of the outflow. This feature of the models does not permit tracking the variation of the NPV due to variation of the number of failures per year and the variation of their times of occurrence. In view of the drawbacks of the classical models, a dynamic discounted cash-flow model based on a direct Monte Carlo simulation for determining the variation of the NPV as a function of the failure pattern appears to be an attractive alternative. The model incorporates the losses from failures, the capital costs and the income generated from selling the product. The value analysis example in this chapter involves a comparison of the economic performance of an eight-unit dual-Control-channel Production System with an eight-unit single-Control-channel Production System. The results were obtained from running the discrete-event simulator, used for tracking the NPV for the dual-Control and single-Control Production System. The chapter presents the minimum failure-free operation period (MFFOPα) that is an alternative reliability measure. It is the maximum operating interval, the probability of a critical failure within which does not exceed the pre-set level α.
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Risk-Based Reliability Analysis and Generic Principles for Risk Reduction - 3 – METHODS FOR ANALYSIS OF COMPLEX RELIABILITY NETWORKS
Risk-Based Reliability Analysis and Generic Principles for Risk Reduction, 2007Co-Authors: Michael TodinovAbstract:This chapter discusses a number of methods for System reliability analysis oriented mainly towards Systems with simple as well as complex topology, such as, the method of network reduction and the event-tree method. The essence of the network reduction method, for example, is reducing the entire System to a single equivalent element, by Systematically combining appropriate series and parallel branches of the reliability network. At the end, the reliability of the remaining equivalent element equals the reliability of the initial System. The main drawback of the network reduction method is its limited application area—only to networks with relatively simple topology, usually series-parallel. Many Production Systems such as the dual-Control Production System do not have a simple series-parallel topology and cannot be handled by this method. The decomposition method avoids this limitation. The other methods discussed in this chapter with their drawbacks are: decomposition method for reliability analysis of Systems with complex topology; System reliability analysis based on minimum path sets and cut sets; Monte Carlo simulation algorithms for System reliability analysis based on testing minimal paths or minimal cut sets; and System reliability analysis based on finding paths through working components in reliability networks. Algorithms used for determining the existence of a path in complex reliability networks and an algorithm for determining the reliability of a complex reliability network are explored in this chapter. The algorithm for System reliability analysis is demonstrated on two test networks of type ‘full square lattice’ and ‘quasi-complete graph.’
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RELIABILITY ANALYSIS OF COMPLEX SystemS BASED ON THE LOSSES FROM FAILURES
International Journal of Reliability Quality and Safety Engineering, 2006Co-Authors: Michael TodinovAbstract:The conventional reliability analysis is based on the premise that increasing the reliability of a System will decrease the losses from failures. In this paper it is demonstrated that increasing the reliability of the System does not always mean decreasing the losses from failures. An inappropriate increase of the reliability of the System may lead to a simultaneous increase of the losses from failure. In other words, a System reliability improvement, which is disconnected from the losses from failure does not necessarily reduce the losses from failures. An efficient discrete-event simulation model and algorithm have been proposed for reliability analysis based on the losses from failure for Production Systems with complex topology. The model links reliability with losses from failures. A new algorithm has also been developed for System reliability analysis related to Productions Systems based on multiple Production units where the absence of critical failure means that at least m out n Production units are working. The parametric study conducted on the basis of the developed models revealed that a dual-Control Production System is characterized by enhanced Production availability, which increases with increasing the number of Production units in the System. A Production unit from a dual-Control Production System including multiple Production units is characterized by a larger availability compared to a Production unit from a dual-Control Production System including a single Production unit. The proposed approach has been demonstrated by comparing the losses from failures and the net present values of two competing design topologies: one based on a single-channel Control and the other based on a dual-channel Control. The proposed models have been successfully applied and tested for reliability value analysis of Productions Systems in deepwater oil and gas Production. It is also argued that the reliability allocation in a Production System should be done to maximize the net profit/value obtained from the System. Consequently, a method for setting reliability requirements and reliability allocation maximizing the net profit by minimizing the sum of the capital costs and the expected losses from failures has been proposed. Reliability allocation which maximizes the net profit in case of a System consisting of blocks arranged in series is achieved by determining for each block individually, the reliabilities of the components which minimize the sum of the capital costs and the expected losses from failures.
Chengye Jia - One of the best experts on this subject based on the ideXlab platform.
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A dynamic prediction model of pressure-Control Production performance of shale gas fractured horizontal wells and its application
Natural Gas Industry B, 2020Co-Authors: Ailin Jia, Yunsheng Wei, Cheng Liu, Junlei Wang, Chengye JiaAbstract:Abstract For clarifying the inherent relation between relieving fracture closure and improving the EUR by adopting the pressure-Control Production System for shale gas fractured horizontal wells, and the significance of pressure-Control Production for gas reservoir engineering, a dynamic formation–fracture coupling prediction model for Production performance of fractured horizontal wells was established and solved, with the finite conductivity fracture as basic flow unit and the variable stress sensitivity coefficient introduced. Through a comparison of the calculated results from the established model, classical model and numerical modeling by the Saphir software, the effect of characteristic parameters of stress sensitivity and pressure-Control Production System on the Production performance of fractured horizontal wells was analyzed and verified in two wells. The results show that (1) the calculated results from the established model are basically consistent with those from the classical model and the numerical modeling by the Saphir software; (2) the existence of stress sensitivity makes the fracture conductivity decline with the Production of gas wells, which leads to the decrease of cumulative gas Production; the greater the stress sensitivity, the greater the decrease of cumulative gas Production; (3) although the initial gas Production and cumulative gas Production of shale gas gained by the pressure-Control Production System are low compared with those by the pressure-release Production System, the ultimate cumulative gas Production is higher. Thus, it is more reasonable to adopt a long-term pressure-Control Production System for shale gas fractured horizontal wells. In conclusion, the research results provide a theoretical support for the popularization of pressure-Control Production System of shale gas wells.
Wang Jianqiang - One of the best experts on this subject based on the ideXlab platform.
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pressure drop funnel extension of coalbed methane horizontal well
Journal of Liaoning Technical University, 2012Co-Authors: Wang JianqiangAbstract:To understand the extension properties of pressure drop funnel around coalbed methane horizontal wells,using theoretical analysis and numerical simulation method,the regional pressure drop and inter-well interference process were analyzed in this study.The analysis shows that the inter-well interference effect occurs after three years extraction,and the average recovery rate reaches 60% after five years extraction.Therefore,a Production method is proposed,which uses a three-stage management method to Control bottom hole pressure(BHP).The proposed method realizes pressure drop,improves and stabilizes the Production of horizontal well,and reduces the accident of pump blocking and well repairmen.Study results demonstrates that the horizontal well pressure drop is directly proportional to recovery rate,and the three-stage BHP Control Production System can reduce regional pressure and improve CBM well productivity.