• Journal of the Korean Society for Railway
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• v.12 no.5
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• pp.663-669
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• 2009

In the electrical railway, the increase of tensions in an overhead contact lines is essential to speed-up of train, because current collection quality largely depends on the ratio of a wave propagation speed to a train speed. For Kyungbu high-speed line, a pulley-type tensioning device is required to have a tension variation of maximum 3%. Therefore we developed a pulley-type tensioning device in order to meet tension variation requirement of the high-speed tensioning device. To verify the performance of the developed device, a performance test, overload test and failure test were carried out according to the factory test procedure of the Kyung-Bu High-speed line. Furthermore, we also performed reliability performance through not only a fatigue test in a factory, but also on-line verification test in Chungbuk line for over 1 year. These tests verified that the tensioning device had applicability to a main line.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.6
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• pp.1100-1111
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• 2001

The purpose of this study was to develop fashion On-line store attributes for fashion On-line shopping mall and to identify significant On-line store attributes, influencing consumers'purchase intention of interned fashion product shopping. A questionnaire was administered to 456 adults who had purchasing experience at fashion On-line shopping mall. SPSS 9.0 package was used for data analysis. Factor analysis, $X^2-test$, t-test, frequency, percentage, one-way ANOVA, multiple regression analysis were utilized. The results were as follows; 1. The On-line store attribute dimensions of fashion On-line shopping mall were tangibility, variety, marketing promotion, responsiveness, reputation, price and convenience. 2. The purchase experienced consumers showed higher purchase intention of Internet fashion product shopping and highly perceived about all sub-factors, except reputation. in On-line store attributes that have significantly positive influence on fashion On-line shopping attitudes. The purchase experienced consumers showed more favorable attitudes toward Fashion On-line shopping than non purchase experienced consumers. Attitudes toward Fashion On-line shopping have directly impact on purchase intention of Internet fashion product shopping.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.9
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• pp.14-24
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• 2009

Memory cell array and peripheral circuits are designed for system on panel style frame buffer. Moreover, a parallel test methodology to test multiple blocks of memory cells is proposed to overcome low yield of system on panel processing technologies. It is capable of faster fault detection compared to conventional memory tests and also applicable to the tests of various embedded memories and conventional SRAMs. The various patterns of conventional test vectors can be used to enhance fault coverage. The proposed testing method is also applicable to hierarchical bit line and divided word line, one of design trends of recent memory architectures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.6
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• pp.491-496
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• 2005

In this paper, test on characteristics of 3-phase line-interactive UPS system, known as delta conversion UPS system, is studied. Delta conversion UPS system is new line-interactive UPS system using two series-parallel PWM converters instead of using series inductor in conventional single conversion line-interactive UPS system. It is known that the characteristics of input and output in delta conversion UPS system is much improved by controlling source current of AC lines directly. Here the results on load test, normal/backup mode test, and normal/bypass mode test, which are very important in the test on characteristics of UPS system, is presented. And finally overall evaluation on delta conversion UPS system is given.

• Proceedings of the KOSOMBE Conference
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• v.1990 no.05
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• pp.43-46
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• 1990

Modern society is prevailed a lot of allergies. So, the allergy test is very important. There are many kinds of allergy test. A doctor usually uses skin allergy test among many allergy tests. However, little standadization and objectivity of grading-standard has been established in the skin allergy test. A measurement of the reaction area has been a major objective to perform skin allergy test. Recently, a doctor's method is to measure the reaction area after drawing a line that represents the reaction area on the skin. But this method differs slightly from the real reaction area and individual doctor's measurement is different, because the edge of the reaction area is obscure. In this paper, we propose a algorithm which is able to detect vague edges using the fuzzy set. The algorithm that detects the line and curve is proposed first. Here, the maximum value is calculated by comparing the membership function of the line and curve seperately. We also encode the direction of the line and curve by using 8-direction code. Then, we calculate the reaction area by measuring the pixels which are inside the reaction area. And finally the Allergy grade is decided by grading-standard, and we accomplish faster, the 80re accurate and objective allergy grade decision.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.6
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• pp.436-441
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• 1999

Joule heating effect in EM(Electromigration) test were performed on a bend test structure. EM test is done under high current densities(1.0-2.5MA/cm2), which leads to joule heating. Since joule heating is added to the controlled oven(stress) temperature, themetal line temperature is higher than the stress temperature. The increase in the stress temperature due to joule heating is important because EM phenomena and metal line failure are related to the stress temperature. In this paper, metal line was stressed with a current density of 1.0 MA/$cm^2$, 1.5MA/$cm^2$, 2.0MA/$cm^2$, 2.5MA/$cm^2$, for 1200 sec and temperature increase due to joule heating was less than $10^{\circ}C$. Also it took 30 minutes for the metal line to equalized with oven temperature. Recommendations are given for the EM test to determine the initial resistance of EM test structure under stress temperature and current density.

• IE interfaces
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• v.17 no.3
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• pp.282-293
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• 2004

Line Balancing is the problem to assign tasks to stations while satisfying some managerial viewpoints. Most researches about the Mixed-Model Line Balancing problems are focused on the minimizing the total processing time or the number of workstations. Independently, some research reports consider the balance issues of the physical workloads on the assembly line. In this paper, we are presenting a new mathematical model to accomplish the line balance considering both the processing time and the workloads at the same time. To this, end, we propose an zero-one integer program problem, and we use the Chebyshev Goal Programming approach as the solution method. Some computational test runs are performed to compare the pay-offs between the processing time and the workloads. And, the test results show us that the reliable balanced work schedules can be obtained through the proposed model.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.334-338
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• 2004

KTX has started commercial service from Seoul to Busan and Mokpo since April 1, 2004. The service line is composed of new-high speed line and conventional line. Before KTX is runs, the maximum operational speed on conventional line was 140km/h. In order to reduce the traveling time, operation speed of KTX must be increased on the conventional line. So, we performed test running with prototype HSR-350x and verification of safety was made in $10\%$ speed-up. Korean High Speed Train HSR-350x) was developed by G7 - R&D project. In this study, in safety aspect, several technical reviews are introduced and the possibility for reduction of traveling time is investigated on the conventional line by using HSR-350x.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.1
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• pp.48-59
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• 2018

This paper is mainly concerned with developing the formulae of predicting thermal deformation of steel plate due to multi-line heating. By investigating the results of line heating test and numerical analysis, reasonable heat flux model has been defined. Formulae of predicting the transverse shrinkage and the angular distortion as the dominant thermal deformation types in plate forming by line heating have been derived based on the results of line heating test and numerical analysis with varying plate thickness, heating speed and distance between torches. This paper illustrates how the derived formulae are used in investigating the effect of multi-line heating upon the thermal deformation and how they can be used in defining the limit distance with that there is no interacted effect between torches. This paper ends with describing the extension of the present study.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.11
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• pp.520-526
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• 2006

Corona interferences, such as radio noise, audible noise and television noise, need to be taken into account in the design of HVDC transmission line conductor configuration. Therefore the line designer requires data from which to estimate the corona performance of any set of conductors. To get a sufficiently complete set of design data, it is necessary to examine the corona test of a large number of conductor geometries. This paper presents the results of corona cage test among three types of candidate conductors. It is quite clear from test results that the conductor geometries play an important role in establishing the magnitude of corona noise. Corona noise data from corona cage test are expressed as a statistical distribution of results obtained over long periods of time and various weather conditions. Therefore we can determine an environmentally-friendly conductor bundle for HVDC overhead transmission line. Based on this finding results, various simulations about HVDC line configurations, such as pole space and pole height, will be conducted. And then finally an optimal configuration for HVDC transmission line will be decided.