• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.12
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• pp.3094-3104
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• 1993

The five punch and die sets are selected as the examples of arbitrary cross sections which have two opposite inclined sides. Two kinds of blank shapes are designed for all cross sections. One(h-b1.) is determined by slip-line theory and the other (G-b1.) is determined conventionally as the similar shapes with the cross sections which were used by Gopinathan. As a result of the experimental procedures, the superiority of the blank shapes designed by slip-line theory is verified in the limiting drawing ratio, the uniformity of cup height and the thickness distributions.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.263-266
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• 2002

This paper describes extraction procedure for the center coordinates of steam generator tubes of Youngkwang NPP #6, which are arrayed in triangular patterns. Steam generator tube images taken with wide field-of-view lens and low-light lamp mounted on a ccd camera tend to have low contrast, because steam generator is sealed and poorly illuminated. The extraction procedures consists of two steps. The first step is to process the region with superior contrast in entire image of steam generator tubes and to extract the center points. Using the extracted coordinates in the first step and the geometrical array characteristics of tubes lined up in regular triangle forms, the central points of the rest region with low contrast are estimated. The straight lines from center point of a tube to neighbour points in horizontal and 60, 120$^{\circ}$ degree directions are derived. The intersections of straight line In horizontal direction and slant line in regular triangle direction are selected as the center coordinates of steam generator tubes. The Chi-square interpolation method is used to determine the line's coefficients in horizontal and regular triangle direction.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.488-493
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• 2005

Railload line design of the railroad construction project should be planed considering the variety of quantitative and qualitative factors, and needs to be selected the optimum altinative weighing from VE/LCC analysis of the planned design. The purpose of this research is for showing selecting plan of the optimum railload line and railway bridge applying VE/LCC analysis in selecting the optimum altinative of railroad construction based on quantitative and qualitative factors, such as initial construction cost, maintenance cost, owner and user's requirements. In this research showed the application plan by each stage using data analysis, function analysis, and alternative evaluation of VE/LCC analysis with AHP and LCC analysis program for the selection. This research is proved the rationality and application of the course of selecting the optimum alternative through case application

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.4
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• pp.363-368
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• 2005

This paper proposes an LOS(line-of-sight) guidance system of a ship for path following. From the viewpoint of a control configuration, guidance is a special type of compensation algorithm that is placed in front of the controller to accomplish navigational objects. A guidance system generates a reference trajectory for trajectory tracking or path control and decides the desired velocity, position and heading angle. A control system executes commands based on a reliable guidance law during navigation. An LOS vector from the vessel to a point on the path between two way-points in straight-line navigation or a point among turning circle in turning navigation is selected, and then a heading angle is calculated to converge the desired path based on the LOS vector. The LOS guidance law is defined for the straight-line and the turning circle, respectively. The effectiveness of the suggested LOS guidance system is assured through computer simulation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.11
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• pp.2089-2094
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• 2009

The fault current has increased due to growth of distributed generations for the large power demand in power distribution system. To solve some problem such as excess of the circuit breaker's cut-off ratings, the superconducting fault current limiter(SFCL) has been progressed. However, the operational characteristics of the relay is changed by SFCL. Therefore, the proper impedance for the SFCL should be selected to keep protective coordination with the SFCL when SFCL is introduced on the neutral line of main transformer in distribution system. In this paper, the proper normal conducting resistance was suggested to solve the problem in case of the protection coordination with SFCL.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.441-444
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• 2004

Each electrical apparatus radiates various infrared as the condition of surface and load current. Because heat distribution of the apparatus changes as the condition, it is able to analyze the condition of the apparatus by using the distribution. However, methods having been used to measure the heat distribution cannot compare normal condition with abnormal, and the apparatus has diagnosed by intuition. This paper deal with a program that is able to analyze changed temperature distribution. The program is to analyze temperatures on pixels in selected region of interest or position and is able momently and logically to analyze condition of the apparatus. The results are able to apply to a on-line monitoring system.

• Journal of Fashion Business
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• v.6 no.3
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• pp.52-59
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• 2002

Companies desire to increase total profits. Consumer's buying behavior depends on the nature of the product just like look, touch, and feel of fabric in apparel shopping on-line with Quick Response based mass-customization. The purpose of this study is to investigate the consumer's texture sensibility from textile image under on-line environment in order to give the direction for marketing strategy in apparel ebusiness. Total 8 kinds of textile swatches representing each of 8 texture-sensibility-axes were selected for this research on the basis of finding in previous studies. The analyses of 60 questionnaires were conducted by frequency, mean, and standard deviation using SPSS 10.0. The results of this research were as follows: Under on-line environment, consumers recognized Homespun as natural, strong, and warm texture sensibility, but not as glossy, and transparent. Oxford was recognized by consumers as refreshing, and plain texture. Consumers recognized Muslin as flat and refreshing, Melton not as transparent but as warm, strong, dense, and natural, Habutae as thin, transparent, refreshing, flat, glossy, and soft, Linen as sandy, Suede not as transparent but as strong, and warm, and Terry as warm, and dense.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.6
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• pp.849-852
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• 2021

This paper presents a vision based tire mold inspection system where mold defects are inspected and the sizes of specific parts of the mold are measured. There are a lot of challenging issues as letters and pictures of intaglio are engraved on a bright surface of the tire mold. To solve the issues, we carefully selected a line-scan camera and a line light. In addition, we used PLC to control the mechanical parts. The developed system provides inspection of misspelled and deformed letters as well as a variety of the functions such as size measurement of engraved regions and inspection report file creation.

• Journal of the Semiconductor & Display Technology
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• v.21 no.2
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• pp.1-6
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• 2022

This computational investigation of micro-sized particle dispersion concerns the fume particle contamination over target surface in high-precision laser line machining process of semiconductor and display device materials. Employing the random sampling based on probabilistic fume particle generation distributions, the effects of sphericity for nonspherical fume particles are analyzed for the fume particle dispersion and contamination near the laser machining line. The drag coefficient correlation for nonspherical particles in a low Reynolds number regime is selected and utilized for particle trajectory simulations after drag model validation. When compared to the corresponding results by the assumption of spherical fume particles, the sphericity of nonspherical fume particles show much less dispersion and contamination characteristics and it also significantly affects the particle removal rate in a suction air flow patterns.

• Educational Technology International
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• v.6 no.2
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• pp.101-111
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• 2005

This study was to examine effects of On-Line Community Assisted Small Group Peer Tutoring(OCSPT) on university students' learning strategies. To achieve the purpose, twenty-eight university students were randomly selected. Fourteen students participated in OCSPT and they were divided into small groups consisted of 2 to 5. Students in experimental group participated in OCSPT for total thirty-four hours during sixteen weeks. There is no treatment for the other fourteen students in control group. To measure students' learning strategies, Motivated Strategies for Learning Questionnaire (MSLQ) shorts has been used. The result revealed that students in experimental group showed higher possession than control group in resource-management strategy(p<.05). However, there were no significant difference between both groups in cognitive and motivative strategies.