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Manufacturing systems design is a complex task and is crucial to the future of a company. Computer simulation provides an efficient and visual method for system designers. The popularity of simulation is owing to its ability to model systems in a fast and cost‐effective way, its flexibility and its ability to model the time dynamic behavior of systems. This paper demonstrates the use of computer simulation as a tool for assisting managers and engineers in the design and analysis of a new manufacturing system by presenting a case study. The case study is a study of proposed instrument panel/crashpad production and assembly work‐cells in an automotive industry. The emphasis on the case study was to evaluate alternative designs, predict system performance, detect any potential problems, experiment with system parameters and determine the sensitivity of the system to these parameters. The case study results show that computer simulation can be a useful decision‐making support tool for the analysis of the system performance and the selection of the design alternatives before the system is actually implemented.

Management simulations are used in many adult education programmes. Yet, little has been written about how people learn through participation in such simulations. After a description of how management simulations work, we propose four ideas to support the increasingly held belief that it is worthwhile to use management simulations in business education. Because management simulations are able to provide relevant, individualised, and experience‐based learnings for both programme participants and the facilitators, their use in management education is likely to increase several fold by the year 2000.

Simulation is a powerful analytical technique that plays a role in the development of managers′ problem‐solving and decision‐making skills as well as those skills related to effecting organisational change and dealing with the dynamics of organisational behaviour. An overview is presented of simulation in the health services setting. Two specific hospital simulation applications concerning the design of a same‐day surgery unit and the reallocation of beds among services are described. Each examines the impact on managerial skills and how simulation enhanced those skills. Finally, the implications of using simulation as a strategy for management development are discussed.

The purpose of this paper is to analyse, in a finite element simulation, the failure of a multilayer printed circuit board (PCB), exposed to an impact load, to better evaluate the reliability and lifetime. Thereby the focus was set on failures in the outermost epoxy layer.

The fracture behaviour of the affected material was characterized. The parameters of a cohesive zone law were determined by performing a double cantilever beam test and a corresponding simulation. The cohesive zone law was used in an enriched finite element local simulation model to predict the crack initiation and crack propagation. Using the determined location of the initial crack, the energy release rate at the crack tip was calculated, allowing an evaluation of the local loading situation.

A good concurrence between the simulated and the experimentally observed failure pattern was observed. Calculating the energy release rate of two example PCBs, the significant influence of the chosen type on the local failure behaviour was proven.

The work presented in this paper allows for the simulation and evaluation of failure in the outermost epoxy layers of printed circuit boards due to impact loads.

Simulation is one of the most widely used tools within management science. The teaching of simulation has traditionally involved theory and practical model development. With the advent of modern software, practical model development can be undertaken with very little knowledge of simulation theory. This enables students who are more able in model building to develop their capabilities in this area and use their strengths to help develop the theoretical knowledge as they progress. This paper demonstrates how a little knowledge of the principles of simulation has been used to help students to develop working models by prototyping.

Induction machines for traction applications are operated at working points of high ferromagnetic saturation. Depending on the working point, a broad spectrum of harmonic frequencies appears in the magnetic flux density of induction machines. Detailed loss analysis therefore requires local and temporal highly resolved nonlinear field computation. This loss analysis can be performed in the post processing of nonlinear transient finite element simulations of the magnetic circuit. However, it takes a large number of transient simulation time steps to build up the rotor flux of the machine.

In this paper, hybrid simulation approaches that couple static FEA, transient FEA and analytic formulations to significantly decrease the number of simulation time steps to calculate the magnetic field in steady state are discussed, analyzed and compared.

The proposed hybrid simulation approaches drastically decrease the simulation time by shortening the transient build-up of the rotor flux. Depending on the maximum error of the rotor flux linkage amplitude compared to the steady state value, a reduction of simulation time steps in the range of 55.5 to 98 per cent is found.

The presented hybrid simulation approaches allow efficient performing of the transient FE magnetic field simulations of induction machines operated as traction drives.

The University Council for Educational Administration (UCEA) is a principal producer of instructional simulations for preparing educational administrators. The most recent simulation product of the Council is the Monroe City Simulation, parts of which are currently being disseminated and other parts of which are still in various stages of planning and development. The authors describe in this article five generic issues which UCEA simulation developers have had to resolve and which continue to face others engaged in similar kinds of development work. The issues described include those of (1) the use of theoretical vs. empirical models, (2) realism, (3) bias, (4) complexity and (5) learning effects.

Typical assembly cell development requires that the hardware be mostly functional before significant software development can begin. Utilizing a software simulation of the hardware allows concurrent development of the hardware and software and provides many benefits including reduced time to market. Traditional simulation tools, though, are geared towards prototyping and early application development, but for advanced applications are of little or no use during later stages of development and deployment. The Cimetrix CODE (Cimetrix Open Development Environment) system provides a unique solution that supports development of a single software application that can drive not only the simulation, but also the physical machine, without the use of a translator. CODE applications run on Windows NT and can take full advantage of the wide range of third party software and hardware available on that platform. This article will explore the use of simulation throughout the life cycle of an assembly cell, including project definition, development and maintenance, and discuss the benefits that simulation can provide.

In the last 10 years simulation has become an integral tool in planning and running complex logistic systems. In the future the application of simulation in logistics will increase still further as discussed by Axel Kuhn and Rolf Schmidt of the Fraünhofer Institute for Transport Engineering and Physical Distribution.

This paper describes the use of simulation in a large manufacturing organisation and analyses how it could have been used more fully. Although the benefits from using simulation were clear, it was seen that the technique could have been deployed more effectively by considering the organisational context of the use. From the analysis of the case study, certain recommendations are made on how to maximise the benefits from simulation within the organisation, thereby extending the benefits from what is often a considerable investment in developing a simulation model. Recent developments in simulation software in terms of improvements in usability and integration with organisational data are seen to increase the feasibility of a wider role for simulation if the organisational barriers discussed can be overcome.