• Transactions of Materials Processing
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• v.12 no.4
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• pp.302-307
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• 2003

Hot rolled strip is cooled by air and water in Run-Out-Table. In this process, phase transformation and shape deformation occurs due to temperature drop. Because of un-ideal cooling condition of ROT, irregular shape deformation and phase transformation arise in the strip. which affect the strip property and lead to the residual stress of strip. And these exert effects on the following processes, coiling process, coil cooling process, and re-coiling process. Through these processes, the residual stress becomes higher and severe. For the prediction of residual stress distribution and shape deformation of final product, Finite element(FE) based model was used. It consists of non-steady state heat transfer analysis, elasto-plastic analysis. thermodynamic analysis and phase transformation kinetics. Successive FEM simulation were applied from ROT process to coil cooling process. In each process simulation, previous process simulation results were used for the next process simulation. The simulation results were matched well with the experimental results.

• International Journal of Automotive Technology
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• v.6 no.3
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• pp.277-283
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• 2005

Formability simulation of automotive panels at early design phases can reduce product and tooling development time and cost. However, for the simulation to be effective in leading the design process, fast and reliable results should be achieved with limited design definition and minimum modeling effort. In this paper, nonlinear finite element analysis is used to develop an automated process for the formability simulation of automotive body panels at early design phases. Due to the limited design definition at early design phases, the automated simulation process is based on the plane strain analysis for selected number of typical sections along the panel. Therefore, an entire panel can be analyzed with few sections. The state of plane strain can be easily induced, during simulation through symmetry and applied boundary conditions that simplify the modeling process. To study the reliability and effectiveness of the developed simulation process, the analytical results are compared with measured results of production automotive body side panels. The comparison demonstrates that the developed simulation process is reliable and can be effective for analyzing sheet metal formability, in early vehicle development phases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.924-929
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• 2007

This paper introduces a simulation model regarding the process analysis of a LED assembly process. The objective of the simulation model is to evaluate the performance of various design aspects of process alternatives. To develop the simulation model, a time study is performed for each process. Next, by using ARENA, a simulation model is conducted based on the process analysis and the line balancing methodology. We found out several problems for the assembly process, and then suggest several alternatives to improve the system.

• Proceedings of the Korea Society for Simulation Conference
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• 1999.04a
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• pp.94-99
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• 1999

In this Paper, the estimation method of painting process in the automobile plant using computer simulation techniques is studied to improve the bottle neck process, the weak point and the productivity. For model and analysis, Promodel is used which is a manufacturing oriented simulation software developed by Promodel corporation in the U.S.A. Firstly the result of the simulation shows that we can obtain capability improvement in the system performance using computer simulation. Secondly, the optimum system specification is decided by comparing reports generated by scenario in simulation program find out the suitable conditions. Finally, the speed of conveyor and a pitch of painting body as the most critical parameters are chosen on the basis of exhaustive field evaluation to study their effects o the capacity of the process. The best alternative condition for the maximum capacity of the process is selected by computer simulation.

• Proceedings of the Korea Society for Simulation Conference
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• 2001.05a
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• pp.169-169
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• 2001

With the aid of fast computing power, resampling techniques are being introduced for simulation output analysis (SOA). Autocorrelation among the output from discrete-event simulation prohibit the direct application of resampling schemes (Threshold bootstrap, Binary bootstrap, Stationary bootstrap, etc) extend its usage to time-series data such as simulation output. We present a new method for inference from a regenerative process, regenerative bootstrap, that equals or exceeds the performance of classical regenerative method and approximation regeneration techniques. Regenerative bootstrap saves computation time and overcomes the problem of scarce regeneration cycles. Computational results are provided using M/M/1 model.

• Journal of the Korea Society for Simulation
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• v.24 no.3
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• pp.55-60
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• 2015

This paper presents an SBA (simulation-based acquisition) effectiveness analysis environment using the RUP (Relational Unified Process) model. The RUP model has 4 phases which cover the whole development steps such as requirement analysis, design, development and test. By applying the RUP model, SW development can be represented with the iterations of developments for each phase. Such a characteristics of the model would make the model suitable for defense acquisition. In this paper, we show the relation between the RUP model and V process model, which is the foundation for defense acquisition. In order to show how the model could be applied to SBA effectiveness analysis, graphical user interfaces for the analysis are presented at the end of the paper.

• International Journal of Automotive Technology
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• v.7 no.2
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• pp.217-226
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• 2006

To maintain competitiveness in the modern automotive market, it is important to carry out process planning concurrently with new car development processes. Process planners need to make decisions concurrently and collaboratively in order to reduce manufacturing preparation time for developing a new car. Automated generation of a simulation model by using the integrated process plan database can reduce time consumed for carrying out a simulation and allow a consistent model to be used throughout. In this research, we developed a web-based system for concurrent and collaborative process planning and flow analysis for an automotive general assembly using web, database, and simulation technology. A single integrated database is designed to automatically generate simulation models from process plans without having to rework the data. This system enables process planners to evaluate their decisions quickly, considering various factors, and easily share their opinions with others. By using this collaborative system, time and cost put into the assembly process planning can be reduced and the reliability of the process plan would be improved.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.21-29
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• 2010

This research suggests a simulation model regarding the performance analysis of the Heat-Shrink-Tube manufacturing process using a simulation method. To analyze this study, firstly, we have collected the operating data from 'A' automobile parts company. Secondly, we have analyzed the collected data to apply a simulation model. Thirdly, we have developed a simulation model to experiment the process analysis and the line balancing methodology. The proposed simulation model can be executed by various input data without changing the simulation model and the performance of the Heat-Shrink-Tube Manufacturing system can be calculated by this model.

• Korean Journal of Computational Design and Engineering
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• v.16 no.6
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• pp.449-457
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• 2011

The productivity improvement is indispensible to shipbuilding industry for maintaining the world's No. 1. Simulation based production recently has been an issue as prat of efforts to high efficiency production and Korean shipyards requests simulation system tools specialized in a shipbuilding industry. IT convergence project between conventional shipbuilding industry and IT simulation technology has been carried out and integrated simulation framework was proposed as a way to overcome sporadic developments. The framework would provide reusability of kernels and modules and also ensure for expansibilities to other production simulations. The fact that production simulation system should reflect shipyard requirement would be most important. We suggest an analysis process of customer requirements and functional requirements for production simulations. It is partially based on concepts of software engineering and axiomatic design. The process is applied to a design of configuration for simulation framework.

• IE interfaces
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• v.18 no.1
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• pp.22-34
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• 2005

This paper introduces a simulation model which is based on the process analysis of a semiconductor company. The objective of the simulation modelis not only to estimate the overall performancesof the company but also to evaluate the performances of various operation rules for shop floor control. First, in order to develop the simulation model, a time study is performed for each process after analyzing the processes for the company. Second, by using ARENA, a simulation model is constructed based on the process analysis and the time study. After the simulation model is tested and run, its results are discussed.