scholarly journals Simultaneous Planning of Production, Setup and Maintenance for an Unreliable Multiple Products Manufacturing System

2021 ◽  
Vol 6 (5) ◽  
pp. 24-34
Author(s):  
Guy Richard Kibouka ◽  
Jean Brice Mandatsy Moungomo ◽  
Adoum Traoré Ndama
Keyword(s):  
Production System ◽  
Manufacturing System ◽  
Numerical Approach ◽  
Joint Optimization ◽  
Maintenance Strategy ◽  
Repair Rate ◽  
Hjb Equations ◽  
Corrective Maintenance ◽  
Multiple Products ◽  
Maintenance Activities

The work presented in this paper addresses the problem of joint optimization of the production, setup and corrective maintenance activities of a manufacturing system. This system consists of a machine subject to breakdowns and repairs and producing two types of parts. A corrective maintenance strategy whose repair rate depends on the number of setup operations already performed on the production system is considered in this work. The objective of this research is to propose a policy that controls production, setup, and corrective maintenance. The contribution of this paper is through the control of the repair rate, combined with the planning of production and setup in a dynamic and stochastic context. Optimality conditions in the form of Hamilton-Jacoby-Bellman (HJB) equations are obtained and a numerical approach is proposed in order to deal with the joint optimization issues. Extensive simulations are performed to address many scenarios that illustrate the interactions between production, setup and maintenance activities.

scholarly journals Construction of Intelligent Integrated Model Framework for the Workshop Manufacturing System Via Digital Twin

2021 ◽  
Author(s):  
Zhongyu Zhang ◽  
Zhenjie Zhu ◽  
Jinsheng Zhang ◽  
Jingkun Wang
Keyword(s):  
Real Time ◽  
Production System ◽  
Manufacturing System ◽  
System Optimization ◽  
Production Cycle ◽  
Model Framework ◽  
The Real ◽  
Digital Twin ◽  
Twin Model ◽  
Information Layer

Abstract With the drastic development of the globally advanced manufacturing industry, transition of the original production pattern from traditional industries to advanced intelligence is completed with the least delay possible, which are still facing new challenges. Because the timeliness, stability and reliability of them is significantly restricted due to lack of the real-time communication. Therefore, an intelligent workshop manufacturing system model framework based on digital twin is proposed in this paper, driving the deep inform integration among the physical entity, data collection, and information decision-making. The conceptual and obscure of the traditional digital twin is refined, optimized, and upgraded on the basis of the four-dimension collaborative model thinking. A refined nine-layer intelligent digital twin model framework is established. Firstly, the physical evaluation is refined into entity layer, auxiliary layer and interface layer, scientifically managing the physical resources as well as the operation and maintenance of the instrument, and coordinating the overall system. Secondly, dividing the data evaluation into the data layer and the processing layer can greatly improve the flexible response-ability and ensure the synchronization of the real-time data. Finally, the system evaluation is subdivided into information layer, algorithm layer, scheduling layer, and functional layer, developing flexible manufacturing plan more reasonably, shortening production cycle, and reducing logistics cost. Simultaneously, combining SLP and artificial bee colony are applied to investigate the production system optimization of the textile workshop. The results indicate that the production efficiency of the optimized production system is increased by 34.46%.

Integrated maintenance/spare parts management for manufacturing system according to variable production rate impacting the system degradation

2020 ◽  
Vol 28 (1) ◽  
pp. 72-84 ◽  
Author(s):  
Sofiene Dellagi ◽  
Wajdi Trabelsi ◽  
Zied Hajej ◽  
Nidhal Rezg
Keyword(s):  
Production Rate ◽  
Preventive Maintenance ◽  
Manufacturing System ◽  
Planning Horizon ◽  
Sensitivity Study ◽  
Spare Parts ◽  
Rate Variation ◽  
Maintenance Strategy ◽  
Spare Parts Management ◽  
The Impact

This study develops an analytical model in order to determine an optimal integrated maintenance plan and spare parts management. We consider a manufacturing system, producing only one type of product, over a finite planning horizon H equal to the sum of all production periods and the production quantity of each period is known. This system is subject to a continuously increasing degradation rate. That is why a preventive maintenance strategy is adopted in order to face the increasing failure rate. We noted that contrarily to the majority of studies in literature, we take into account the impact of the production rate variation on the manufacturing system degradation and consequently on the adopted optimal maintenance strategy. In addition, the real need of spare parts relative to the scheduled maintenance actions is taken into account. In fact, the purpose of our study consists at determining the optimal preventive maintenance frequency and the optimal quantity of spare parts to order by minimizing a total cost, including maintenance and spare parts management. Numerical examples are presented along with a sensitivity study in order to prove the use of the developed model for deriving the optimal integrated strategy for any instance of the problem.

Convertibility and Productivity of Manufacturing System Configurations

Manufacturing ◽  
2003 ◽  
Author(s):  
Valerie Maier-Speredelozzi ◽  
Theodor Freiheit ◽  
S. Jack Hu
Keyword(s):  
Manufacturing Systems ◽  
Manufacturing System ◽  
Reconfigurable Manufacturing ◽  
Productivity Analysis ◽  
System Productivity ◽  
Require Time ◽  
Multiple Products ◽  
Productivity Losses ◽  
System Configurations

Conversions between different products manufactured on the same system often require time-consuming shut-downs and thus, incur productivity losses. Producing multiple products on the same line complicates system productivity analysis because production rates, failure rates, and repair rates vary between different part types. Certain manufacturing system configurations have advantages when convertibility is considered. Ideally, manufacturing lines that produce a mix of products or undergo a product rollover would not see any loss in production relative to lines that continuously produce a single product throughout the system lifetime. This paper investigates the interactions between convertibility and productivity for different manufacturing system configurations, using analytical methods. The methods presented in this paper can be applied to assembly or machining stations in dedicated, flexible, or reconfigurable manufacturing systems. When designing such systems, it is important to recognize that more convertible systems are more productive over the long-term, as product designs change.

NATURAL GAS-FIRED POWER PLANTS VALUATION AND OPTIMIZATION UNDER LÉVY COPULAS AND REGIME SWITCHING

2017 ◽  
Vol 20 (01) ◽  
pp. 1750004 ◽  
Author(s):  
NEMAT SAFAROV ◽  
COLIN ATKINSON
Keyword(s):  
Natural Gas ◽  
Regime Switching ◽  
Power Plants ◽  
Control Strategies ◽  
Numerical Approach ◽  
Spot Price ◽  
Operating Characteristics ◽  
Hjb Equations ◽  
Explicit Finite Difference ◽  
Hamilton Jacobi Bellman

In this work, we analyze a stochastic control problem for the valuation of a natural gas power station while taking into account operating characteristics. Both electricity and gas spot price processes exhibit mean-reverting spikes and Markov regime-switches. The Lévy regime-switching model incorporates the effects of demand-supply fluctuations in energy markets and abrupt economic disruptions or business cycles. We make use of skewed Lévy copulas to model the dependence risk of electricity and gas jumps. The corresponding coupled Hamilton–Jacobi–Bellman (HJB) equations are solved by an explicit finite difference method. The numerical approach gives us both the value of the plant and its optimal operating strategy depending on the gas and electricity prices, current temperature of the boiler and time. The surfaces of control strategies and contract values are obtained by implementing the numerical method for a particular example.

Process Modeling for Production System Based on Matrix Mapping

2010 ◽  
Vol 156-157 ◽  
pp. 1497-1500 ◽  
Author(s):  
Meng Qi Li ◽  
Dong Ying Li
Keyword(s):  
Process Modeling ◽  
Production System ◽  
Process Model ◽  
Manufacturing System ◽  
Production Systems ◽  
System Modeling ◽  
Three Dimensional ◽  
Modeling Methods ◽  
Mapping Technology ◽  
Matrix Mapping

In order to reduce the work of repeated nad iterative of process model for manufacturing system, the paper proposed the establishment of three-dimensional "product - process - property" of the modeling methods with matrix mapping technology and mapped products, function, performance, process to model of production system according to the steps. Production system modeling of light-box as a case to detail description of production systems and process modeling. The modeling method with convenience, comprehensive, integrated, inheritable, and sometimes with large amount of calculation.

Sign in / Sign up

Export Citation Format

Share Document