• Journal of Institute of Control, Robotics and Systems
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• v.15 no.12
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• pp.1240-1245
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• 2009

The throughput characteristics of the cluster tool with dual blade robot are analyzed. Using equipment's cycle time chart of the equipment, simple analytic form of the throughput is derived. Then, several important throughput characteristics are analyzed by the throughput formula. First, utilization of the process chamber and the robot are maximized by assigning the equipment to the process whose processing time is near the critical process time. Second, rule for selecting optimal number of process chambers is suggested. It is desirable to select a single process chamber plus a single robot structure for relatively short time process and multi process chambers plus a single robot, namely cluster tool for relatively long time process. Third, throughput variation between equipments due to the wafer transfer time variation is analyzed, especially for the process whose processing time is less than critical process time. And the throughput and the wafer transfer time of the equipments in our fabrication line are measured and compared to the analysis.

• Laser Solutions
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• v.10 no.3
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• pp.15-24
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• 2007

In this paper laser micromachining system design process for commercialization is suggested. The constructed system design process is properly adjusted for laser micromachining area after tailoring engine process of system engineering process such as requirement analysis, functional analysis and allocation, system synthesis and system optimization process. In the current laser machining system design, system components and specifications are determined on the basis of experimental experience which a laser is being used in machining some materials as well as the current machining and research trend. In this paper, however, systematic process is suggested in addition to experimental experience, which the laser and system components and their specifications are decided in the process of definition of functional requirements and engine design variables of system to satisfy the customer's requirements.

• 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 Korean Society of Industrial and Systems Engineering
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• v.25 no.2
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• pp.1-10
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• 2002

Process capability indices are widely used in industries and quality assurance system. In past years, process capability analysis have been used to characterize process performance on the basis of univariate quality characteristics. However, in actual manufacturing industrial, statistical process control (SPC) often entails characterizing or assessing processes or products based on more than one engineering specification or quality characteristic. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index $MC_{pm}^+$ using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.76.4-76
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• 2001

ESR(ElectroSlag Remelting) Process is secondary fine process and melts steels by electric resistance heat and fines the melting steels by an approproate solidification process. The final products are determined through the velocity of melting and the course of solidification in the process that is achieved by way of proper course of solidification. Thus, it is very important to monitor and control the process parameters which affects the melting and solidification process to get the high quality products. This paper describes a method to derive the mathematical model and analysis the dynamic characteristics for designing a controller of the ESR processes. The process consists of a melting and solidifying process and electrical system include the contact resistance mechanism ...

• Journal of Information Technology Services
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• v.14 no.2
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• pp.69-86
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• 2015

The current contract awarding process regulated by laws and ordinances is analyzed and more reasonable processes are suggested. To this end, the principle of economic analysis is described with emphasis on the cost-effectiveness analysis, and the laws and ordinances regulating the process are thoroughly examined. The current contract awarding rule is based on the weighted sum of effectiveness score and cost score. This may not conform to the framework of economic analysis where effectiveness is supposed to be measured as an output and cost measured as an input. An improvement is attempted to the defense acquisition system and it is recognized that the economic analysis and policy consideration should be performed separately. Concept of statistical testing is introduced to see if the results of the cost effectiveness analyses show the significant difference between the alternatives. It is suggested that the contract awarding process can be improved by performing significance test followed by the aggregation of the two analyses. A minor improvement is also suggested on the application of current rules.

• Journal of Digital Convergence
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• v.10 no.1
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• pp.87-104
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• 2012

The purpose of this study was to analyze and present of action learning process in education programs for senior officials, engineers, chief executive officers. The main contents of this study is focused on analysis of orientation activities for each step of action learning process, project selection, analysis of problem clarification, review of data research and analysis, analysis of process for seeking of alternative and selecting execution item, comparison and analysis for the results of execution.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.02a
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• pp.274-284
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• 2002

Deep drawing process for rectangular drawn section is different with that for axisymmetric circular one. Therefore deep drawing process for rectangular drawn section requires several intermediate steps to generate the final configuration without any significant defect. In this study, finite element analysis for multi-stage deep drawing process for high precision rectangular cases is carried out especially for an extreme aspect ratio. The analysis is performed using rigid-plastic finite element method with an explicit time integration scheme of the commercial program, LS-DYNA3D. The sheet blank is modeled using eight-node continuum brick elements. The results of analysis show that the irregular contact condition between blank and die affects the occurrence of failure, and the difference of aspect ratio in the drawn section leads to non-uniform metal flow, which may cause failure. A series of experiments for multi-stage deep drawing process for the rectangular cases are conducted, and the deformation configuration and the thickness distribution of the drawn rectangular cases are investigated by comparing with the results of the numerical analysis. The numerical analysis with an explicit time integration scheme shows good agreement with the experimental observation.

• 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.

• Journal of the Korean Society of Safety
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• v.37 no.5
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• pp.22-32
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• 2022

The domestic smart factory is being built and spread rapidly, mainly by mid-sized companies and large enterprises according to the government's active introduction and support policy. But these factories only promote production system and efficiency, so harmfulness and risk factors are not considered. Therefore, to derive harmful risk factors in terms of industrial safety for 12,983 government-supported smart factory workplaces from 2014 to 2019, industrial accident status analysis compared workplaces with automation facilities and government-supported workplaces with automation facilities. Also, to reduce risks associated with domestic smart factory processes, twenty government-supported workplaces with automation facilities underwent analysis, evaluating risks through a status survey using the process evaluation table. In addition, the status survey considered region, size, industry, construction level, and accident rate; the difference in risk according to the structure of the process was confirmed. Based on the smart factory process evaluation results, statistical analysis confirmed that serial, parallel, and hybrid structures pose different risk levels and that the risks of mixed structures are greater. Finally, safety control system application was presented for risk assessment and reduction in the smart factory process, reflecting the results of disaster analysis and actual condition investigation.