• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.2
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• pp.174-183
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• 2018

In the industrial fields, the process capability index has been using to evaluate the variation of quality in the process. The traditional process capability indices such as $C_p$, $C_{pk}$, $C_{pm}$ and $C^+_{pm}$ have been applied in the industrial fields. These traditional process capability indices are mainly applied in the univariate analysis. However, the main streams in the recent industry are the multivariate manufacturing process and the multiple quality characteristics are corrected each other. Therefore, the multivariate statistical method should be used in the process capability analysis. The multivariate process indices need to be enhanced with more useful information and extensive application in the recent industrial fields. Hence, the purpose of the study is to develop a more effective multivariate process index ($MC_{pI}$) using the multivariate inverted normal loss function. The multivariate inverted normal loss function has the flexibility for the any type of the symmetrical and asymmetrical loss functions as well as the economic information. Especially, the proposed modeling method for the multivariate inverted normal loss function (MINLF) and the expected loss from MINLF in this paper can be applied to the any type of the symmetrical and asymmetrical loss functions. And this modeling method can be easily expanded from a bivariate case to a multivariate case.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.2
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• pp.143-151
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• 2019

This study describes a method for analyzing log data generated in a process using process mining techniques. A system for collecting and analyzing a large amount of log data generated in the process of manufacturing an offshore plant piping material was constructed. The analyzed data was visualized through various methods. Through the analysis of the process model, it was evaluated whether the process performance was correctly input. Through the pattern analysis of the log data, it is possible to check beforehand whether the problem process occurred. In addition, we analyzed the process performance data of partner companies and identified the load of their processes. These data can be used as reference data for pipe production allocation. Real-time decision-making is required to cope with the various variances that arise in offshore plant production. To do this, we have built a system that can analyze the log data of real - time system and make decisions.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.150-153
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• 2001

The present work concerns optimal design for the injection molding process of a deflection yoke (coil separator). The optimal design for the injection molding process is developed using design of experiments and finite element analysis. Two design of experiments approaches are applied such as: the design of experiment for mold design and the design the experiments for determination of process parameters. Finite element analyses have been carried out as a design of experiments for mold design: runner system and cooling channel. In order to determine optimal process experiments have been performed for various process conditions with the design of experiments scheduling.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.10
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• pp.923-928
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• 2014

Elongation rolling process is an intermediate process to make the uniform thickness and uniform surface roughness during producing seamless pipes. The thickness and surface roughness of seamless pipes are generally affected by the distance of rolls and guide shoes, the roll shape, and its cross angle. In this study, finite element analysis for shape forming process is based on the analysis model of elongation rolling mill with guide shoes. This paper shows how the cross angle of the roll, the rolling rpm, and the distance of the guide shoe influence on the outer diameter and the thickness of seamless pipes. The rolling rpm did not give much influence on outer diameter.

• Korean Institute of Interior Design Journal
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• no.19
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• pp.53-58
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• 1999

The goal of this paper is to understand the visual information process and the characteristics of behaviour of the architectural design process using visual protocol analysis through the actual experiment by the architect. The visual protocol analysis is developed on the basis of the theories of the visual information processing model and visual mental image, which can explain visual representation in architectural design process. A protocol study is reported in which the experimental data by architect is analyzed through the protocol analysis method. The whole design process is divided into the stage of 9 tasks which are classified into 18 visual representatiov. The results about visual cognition in cognitive science are reviewed and summarized, and these findings will help understand the architectural design nature.

• Journal of Korean Institute of Industrial Engineers
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• v.27 no.1
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• pp.37-46
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• 2001

Business process(workflow) analysis has been recognized as a core step to building information systems. However, most analysts have recognized that deriving consistent business process artifacts even in a simple business domain is very difficult, since most analysis methods give the designers narrative and/or diagrammatic tools that do not support rigorous analysis rules. This often generates inconsistent analysis results, leading to create useless information systems and resulting in tremendous budget wastes. To overcome this weakness, this paper presents a declarative business process modeling method called contract-collaboration net(cc-net), which is not only somewhat formal but also useful to the practitioners. A case study on bank domain is presented to illustrate our approach.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.23-26
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• 2004

This paper describes the analysis of extrusion process and integrity for the condenser tube which is component of the heat exchanger in automobile and air conditioning apparatus. As development of the analysis method using computer, recently. It have been applied to the 3-dimensional hot extrusion process with complex section area of the non-steady statement and then results of the analysis have been applied to optimal die design and process design. As the result, this paper confirmed that used extrusion die of the research is satisfactorily designed to dimensional accuracy. And the stress point of view, condenser tube confirmed that it was influenced by the flow pressure of alternative regrigerants.

• Journal of Korean Society for Quality Management
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• v.22 no.4
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• pp.79-101
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• 1994

In modern manufacturing, a product consists of many components created by different processes. Variations in the individual component dimensions and in the processes may result in unacceptable final assemblies. Thus, engineers have increased pressure to properly set tolerance specifications for individual components and to control manufacturing processes. When a proper variation stack-up analysis is not performed for all of the components in a functional system, all component parts can be within specifications, but the final assembly may not be functional. Thus, in order to improve the performance of the final assembly, a proper variation stack-up analysis is essential for specifying dimensional tolerances and process control. This research provides a detailed case example of the use of variation stack-up analysis using a Monte Carlo simulation method to improve the defect rate of a complex process, which is the commutator brush track undercut process of an armature assembly of a small motor. Variations in individual component dimensions and process mean shifts cause high defect rate, Since some dimensional characteristics have non-normal distributions and the stack-up function is non-linear, the Monte Carlo simulation method is used.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.88-97
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• 1999

In this study, a systematic approach for roll pass design in bar rolling was studied. To minimize the trial and errors in the process design, a roll CAD system and a FE analysis system were combined. Based on the system, a methodology for roll pass design by FEM was studied. At first, designed process was compared with the FE analysis results and process redesign based on the FEM results was performed to obtain the specified final geometry. Then, empirical formula for roll speed set-up was compared with the FE analysis results. Further study on various simulations for bar rolling will help in making up for the inaccuracy in the currently used empirical roll speed rules. In addition, verification of the accuracy of the FE analysis system must be performed using experimental data in the industry.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.4
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• pp.44-49
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• 2008

The characteristic of magnesium alloy is the most light in utility metal, the effect of electromagnetic wave interception, excellent specific strength and absorptiveness of vibration. Although magnesium alloy with above characteristic is a subject matter which is suitable in world-wide tendency of electrical component frame, sheet magnesium alloy is difficult to process. Therefore, forming analysis of sheet magnesium alloy and applying warm-working to process are indispensable. Among Finite element method, the static implicit finite element method is applied effectively to analyze sheet magnesium alloy stamping process, which include the forming stage. In this study, it was focused on the crack, wrinkling and spring back on sheet magnesium alloy stamping by the static implicit analysis. According to this study, the result of simulation will give engineers good information to access the forming technique on sheet magnesium alloy. And its application is being increased especially in the production of electrical component frame for the cost reduction, saving of defective ratio, and improvement of Productivity.