• Transactions of Materials Processing
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• v.8 no.5
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• pp.498-506
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• 1999

The metal forming processes of aluminum alloy wheel forging at elevated temperature are analyzed by the finite element method. A coupled thermo-mechanical model for analysis of plastic deformation and geat transfer is adapted in the finite element formulation. In order to consider the strain-rate effects on material properties and the flow stress dependence on temperatures, rigid-viscoplasticity is introduced in this formation. In this paper, several process conditions were applied to the dimulation such as die speed, rib thickness, and depth of die cavity. Simulation results are compared, and discussed with each case. Metal flow, die pressure distributions, temperature distributions, velocity fields and forging loads are summarized as basic data for process design and selection of a proper press equipment.

• Journal of Information Technology Services
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• v.10 no.1
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• pp.89-103
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• 2011

ITS (Intelligent Transportation System) has been more popular but ITS project managements remain complex because of diverse stakeholders and multidisciplinary processes of ITS. The multidisciplinary process enforces specialized competencies on ITS project managers comparing to other system integration project managers. In this paper, we derived core competencies of ITS projects from previous researches, built the hierarchy of the competencies, and employed AHP (Analytic Hierarchy Process) surveying ITS project managers and auditors with the hierarchy. Finally, we analyzed the difference of evaluation model on ITS project manager between project managers and auditors using Mann-Whitney U test. Additionally we suggest a method of building MECE (Mutually Exclusive and Collectively Exhaustive) structure for AHP using the HoQ (House of Quality). We expect our model to give some inspirations for raising capable ITS project managers and selecting a proper project manager for an ITS project.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.6
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• pp.802-810
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• 1998

The purpose of this study is to find the analytic solution of determining the optimal capacity of processes and storages to meet the product demand. Recent trend to reduce product delivery time and to provide high quality product to customer requires the increasing capacity of storage facilities. However, the cost of constructing and operating storage facilities is becoming substantial because of increasing land value, environmental and safety concern. Therefore, reasonable decision making about the capacity of processes and storages is important subject for industries. The industrial solution for this subject is to use the classical economic lot sizing method, EOQ(Economic Order Quantity) model, trimmed with practical experience but the unrealistic assumption of EOQ model is not suitable for the chemical plant design with highly interlinked processes and storages. This study, a first systematic attempt for this subject, clearly overcomes the limitation of classical lot sizing method. The superstructure of the plant consists of the network of serially and/or parallelly interlinked processes and storages. A novel production and inventory analysis method, PSW(Periodic Square Wave) model, is applied. The objective function of optimization is minimizing the total cost composed of setup and inventory holding cost. The advantage of PSW model comes from the fact that the model provide a set of simple analytic solution in spite of realistic description of material flow between process and storage. The resulting simple analytic solution can greatly enhance the proper and quick investment decision for the preliminary plant design confronting diverse economic situation.

• Journal of the Korea Safety Management & Science
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• v.13 no.4
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• pp.9-16
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• 2011

Modern systems become more complex and the demand for systems safety goes up sharply. Thus, the proper handling of the safety requirements in the systems design is getting greatly increased attention these days. Hazard analysis has been one of the active areas of research in connection with systems safety. In this paper, we study a subject on how the hazard analysis results can be incorporated in the systems design. To this end we set up a goal on how to systematically generate safety requirements that should reflect hazard analysis results and be implemented in the systems design and development. To do so, we first review the process for systems design and suggest the associated Model. Then the process and results of hazard analysis are analyzed and Modeled particularly with emphasis on the safety data. The resulting data Model incorporating both the hazard analysis and system life cycle is used in the generation of safety requirements. Based on the developed data Model, the generation of the requirements, the construction of requirements DB, and the change management later on is demonstrated through the use of a computer-aided software tool.

• Journal of applied mathematics & informatics
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• v.9 no.1
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• pp.185-195
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• 2002

Previous research has shown that the flow of patients around departments of geriatric medicine and ex-patients in the community may be-modelled by the application of a mixed-exponential distribution. In this proper we considered a ave-compartment model using a continuous-time Markov process to describe the flow of patients. Using a M/ph/c queuing model, we present a way of optimizing the number of beds in order to maintain an acceptable delay probability a sufficiently low level. Finally, we constructed a Java computer simulation, using data from St George's Hospital, London.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.297-300
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• 2009

The roll forming process is often used to manufacture long, thin-walled products such as a pipe. The final cross-section is a comparatively simple open-channel, a closed tube section or a complex profile with several bends. In recent years, that process is often applied to the bumper beam in the automotive industries. In this study, a optimal Center Floor Cross Member manufacturing technology, model deign and proper roll-pass sequences can be suggested by forming number of roll-pass and bending angle, and also effects of the process parameters on the final shape formed by roll forming defects were evaluated.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.199-202
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• 2009

In roll forming process, a sheet metal is continuously progressively formed into a product with required cross-section and longitudinal shape, such as a circular tube with required diameter, wall-thickness and straightness, by passing through a series of forming rolls in arranged in tandem. Tn this process, each pair of forming rolls installed in a forming machine play a particular role in making up the required cross-section and longitudinal shape of the product. In recent years, that process is often applied to the bumper rail in the automotive industries. In this study, a optimal Front Bumper Beam manufacturing technology, model deign and proper roll-pass sequences can be suggested by forming number of roll-pass and bending angle. And also effects of the process parameters on the final shape formed by roll forming defects were evaluated.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.11
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• pp.1073-1079
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• 2009

The proper orthogonal decomposition (POD) method can identify principal modes that optimally capture the energy content from large multi-dimensional data set. In this study unsteady pressure fields on the rotor blade surface of a helicopter in forward flight are expressed by a reduced order model based on the POD method. Special modes containing high energy are analyzed to investigate the aerodynamic characteristics in more efficient way. The CFD simulation of flowfields around helicopter rotor blade in hovering motion is also conducted to validate its prediction with experimental result. In the process 7 modes containing energy ratio 99% from 240 snapshots information are identified and utilized to construct a reduced order model.

• Information Systems Review
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• v.8 no.1
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• pp.25-41
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• 2006

This paper is about how to drive a Business Process Management(BPM) implementation project from selecting a target process to BPM deployment. For guidance of BPM implementation, LG CNS BPM Methodology and enPAM(Entrue Process Assessment Model) were used. This paper focuses on the methodology of process selection and presents a case study from the telecommunication industry. The enPAM consists of three major criteria in determining process priority for BPM system deployment: business impact, BPM adequateness and implementation feasibility. These three criteria can be easily modified for other telecommunication business just as we did to suit this telecom case. Moreover, it could provide useful ideas to companies that consider introducing a BPM solution for process management. Although we propose a comprehensive design methodology for selecting a proper target business process for BPM implementation, more work is still needed to extend the results for rigorous and practical method.

• Korea Journal of Hospital Management
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• v.1 no.1
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• pp.83-107
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• 1996

This study discusses how to rationalize or innovate the managerial practice of the profitability-deteriorated hospitals in Korea, and attempts to suggest proper planning models and strategies to reorient them. For these purposes, the hospitals' financial indicators were analysed, the process of profit planning were reviewed, and strategic assessment were made, using relevant data. The analysis shows that failures both in proper capital investment to fixed assests and in effective containment of operating costs have been causing the worsening of profitability. For the improvement of the profitability management, seven procedural and behavioral strategies were suggested from the innovative and rationalizing perspectives, together with necessary prerequisite conditions to be equipped with for their implementation. This study concludes that the top management should attempt the changs on their own initiative.