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Over the past quarter century, much effort has been devoted to the design and development of simulation modeling languages, and to methods for the development of simulation models themselves. Less effort, however, has been expended on the design of the experimental models upon which simulation studies are based. This paper describes a methodology for the determination of near optimal solutions considering experimental design and simulation modeling. Using this methodology, simulation scenarios are created and analyzed using an analysis of variance (ANOVA)-based experimental design. This paper also presents an application of this method in analyzing a manufacturing system design problem. [ABSTRACT FROM AUTHOR]

Discrete event simulation (DES) has been widely applied to modelling and simulation of computer and engineering systems and is an active field of research that has now evolved from 2D to 3D discrete event simulation. This paper attempts to address several key issues in a successful implementation of DES models based on our own and the previous experiences of others. It describes the common basis, which forms the core for the application of modelling and simulation methodologies that are available to support manufacturing systems analysis, design and performance evaluation. Through a comprehensive literature survey, this paper summarises and compares the most widely used optimisation techniques for simulation of manufacturing systems; an overview of the recent and popular simulation languages and packages available for the modelling and simulation community and the classification of their utility for modelling and simulation of manufacturing systems is also given. Finally, this paper summarises and reports the latest development in the most exciting world wide web (www)-based simulation techniques that represent a future that may completely change the nature and future exploitation of modelling and simulation technology in industry. [ABSTRACT FROM AUTHOR]

Operation flexibility is one of the eight common types of flexibility that exist in flexible manufacturing systems. Dispatching rules are commonly used in loading the machines. This paper studies the effects of different levels of operation flexibility and various dispatching rules on the performance of a flexible manufacturing system. The system performance considered is mean flow time. Simulation results indicate that the mean flow time cannot be always improved by increasing the level of operation flexibility. Altering the dispatching rules seems to have a more significant effect on the mean flow time performance than changing the level of operation flexibility. [ABSTRACT FROM AUTHOR]

A system for geometric and physical simulation of the ball-end milling process using solid modeling is presented in this paper. A commercially available geometric engine is used to represent the cutting edge, cutter and updated part. The ball-end mill cutter modeled in this study is an insert type ball-end mill and the cutting edge is generated by intersecting an inclined plane with the cutter ball nose. The contact face between cutter and updated part is determined from the solid model of the updated part and cutter solid model. To determine cutting edge engagement for each tool rotational step, the intersections between the cutting edge with boundary of the contact face are determined. The engaged portion of the cutting edge for each tool rotational step is divided into small differential oblique cutting edge segments. Friction, shear angles and shear stresses are identified from orthogonal cutting data base available in the open literature. For each tool rotational position, the cutting force components are calculated by summing up the differential cutting forces. The instantaneous dynamic chip thickness is computed by summing up the rigid chip thickness, the tool deflection and the undulations left from the previous tooth, and then the dynamic cutting forces are obtained. For calculating the ploughing forces, Wu's model is extended to the ball-end milling process [21]. The total forces, including the cutting and ploughing forces, are applied to the structural vibratory model of the system and the dynamic deflections at the tool tip are predicted. The developed system is verified experimentally for various up-hill and down-hill angles. [ABSTRACT FROM AUTHOR]

During a manufacturing operation, exceptions may occur dynamically and unpredictably. Their occurrence may lead to the degradation of system performance or, in the worst case scenario, may interrupt the production process. The research proposes a multi-agent architecture for the capacity reconfiguration problem in a reconfigurable manufacturing system (RMS). A policy to manage capacity exchange among manufacturing lines based on due date performance is proposed. The Multi-Agent architecture was built in a simulation environment developed in ARENA® package and it is compared with a dedicated manufacturing and flexible manufacturing systems. The simulations are conducted in several demand scenarios to test the approach in a static and dynamic context. The simulation environment developed can support the planner to decide among the different manufacturing systems by the evaluation of the manufacturing performance. The simulation results, in dynamic environment, showed that the proposed approach leads to similar performance to flexible manufacturing system. [ABSTRACT FROM AUTHOR]

The production system of a wafer fabrication factory is a very complicated process. Job scheduling in a wafer fabrication factory is a very difficult task. To solve this problem, two intelligent scheduling rules are proposed in this study. The intelligent scheduling rules are modified from the well-known fluctuation smoothing rules with some innovative treatments. To evaluate the effectiveness of the proposed methodology, production simulation was also applied in this study. According to experimental results, the proposed methodology outperformed some existing approaches by reducing the average cycle time and cycle time standard deviation, the most important objectives of job scheduling in a wafer fabrication factory. [ABSTRACT FROM AUTHOR]

Increasing consumer awareness towards environmental issues and stricter environmental legislation have forced many manufacturers to set up facilities for product recovery which involves the minimization of the amount of waste sent to landfills by recovering materials and components from returned or end-of-life (EOL) products. Disassembly is an important process in product recovery since it allows for the selective separation of desired parts and materials. EOL products involving missing and/or nonfunctional components increase the uncertainty associated with disassembly yield. Testing, a common solution method, results in high costs. Moreover, if the component is found to be defective, the disassembly time is wasted. Sensor-embedded products (SEPs) can deal with this uncertainty by providing information on the condition of components prior to disassembly. This study evaluates the impact of SEPs on the various performance measures of an air conditioner (AC) disassembly line controlled by a multikanban system which effectively manages material flows considering the stochastic behavior of the disassembly line. First, separate design-of-experiments studies based on orthogonal arrays are carried out for conventional products (CPs) and SEPs. In order to calculate the response values for each experiment, detailed discrete-event simulation models of both cases are developed, considering the precedence relationships among the components of an AC. Then, pairwise t tests are conducted to compare two cases based on different performance measures. The test results show that SEPs improve revenue and profit while achieving significant reductions in backorder, disassembly, disposal, holding, testing, and transportation costs. [ABSTRACT FROM AUTHOR]

The blanking process and structure of the blanked surface are influenced by both the tooling (clearance and tool geometry) and properties of the workpiece material (blank thickness, mechanical properties, microstructure, etc.). Therefore, for a given material, the clearance and tool geometry are the most important parameters. The objective of the present work is to develop a methodology to obtain the optimum punch-die clearance for a given sheet material by simulation of the blanking process. A damage model of the Lemaitre type is used in order to describe crack initiation and propagation into the sheet. A comparative study between numerical and experimental results shows good agreement. [ABSTRACT FROM AUTHOR]