• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.325-329
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• 2002

This paper is intended as an investigation of the interface between Neutral section insulators and pantograph interface. Neutral section insulators are installed at the boundary between AC catenary system and DC catenary system, which should provide electrical insolation between two different catenary systems and pass the trains without interruption. As the number of the pantographs installed on the train increased, which is necessary for the VVVF inverter drive trains introduced in recent years, there occurs an serious aspects of the interaction between pantographs and Neutral section insulators. These effects hinder the automatic switch operation of MCB(Main Circuit Breaker) after passing through the section insulators, and lead to the extra-ordinary wear of FRP insulator material of section insulators. Countermeasures in terms of the interface between the Neutral secton insulators and electric collection system of train are provided too.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1142-1143
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• 2006

Kinik Company pioneered diamond pad conditioners protected by DLC barrier ($DiaShield^{(R)}$ Coating) back in 1999 (Sung & Lin, US Patent 6,368,198). Kink also evaluated Cermet Composite Coating (CCC or $C^3$, patent pending) with a composition that grades from a metallic (e.g. stainless steel) interlayer to a ceramic (e.g. $Al_2O_3$ or SiC) exterior. The metallic interlayer can form metallurgical bond with metallic matrix on the diamond pad conditioner. The ceramic exterior is both wear and corrosion resistant. The gradational design of $C^3$ coating will assure its strong adherence to the substrate because there is no weak boundary between coating and substrate.

• Journal of Korea Foundry Society
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• v.26 no.4
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• pp.191-196
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• 2006

The effects of Bi and Te on the anti-galling behaviors of Ni base alloy were investigated by SEM, galling test and wear test. Anti-galling characteristics depended on the structure of matrix and distribution of Bi-rich phase which was precipitated at grain boundary. The addition of 5 wt% Bi markably enhanced anti-galling properties. The addition of Te caused Bi-rich precipitates to disperse finely and casting structure to form equiaxed type. From the above tests, the concentration of 5 wt% Bi and 1 wt% Te was selected to optimize in this alloy.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.513-518
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• 2001

This research has been performed to estimate the hunting motion hysteresis of railway passenger cars. An old and a new car with almost same structure are chosen as analysis models. To solve effectively a set of simultaneous equations of motion strongly coupled with creep relations, shooting algorithm in which the nonlinear relations are regarded as a two-point boundary value problem is adopted. The bifurcation theory is applied to the dynamic analysis to distinguish differences between linear and nonlinear critical speeds by variation of parameters. It is found that there are some factors and their operation area to make nonlinear critical speed respond to them more sensitivity than linear critical speed. Full-scale roller rig tests are carried out for the validation of the numerical results. Finally, it is concluded that the wear of wheel profile and the stiffness discontinuities of wheelset suspension caused by deterioration have to be considered in the analysis to predict hysteresis of critical speed precisely.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.1
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• pp.137-142
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• 2003

In automotive brake systems, the frictional heat generated can cause high temperature at the interface of rotor and pad which may deteriorate the material properties of the sliding parts and can result in brake fade. Conventionally, a pie-shaped 3-dimentional model is adopted to calculate temperature of ventilated disk using finite element method. To overcome the difficulties in preparing 3D finite element model and reduce the computational time required, the ventilated rotor is to be analyzed, in this study, as an axisymmetric finite element model in which, taking into considerations the effects of cooling passages, a homogenization technique is used to obtain the equivalent thermal properties and boundary conditions for the elements placed at the vent holes. Numerical tests show the proposed procedure can be successfully applied in practice, replacing 3-dimensional thermal analysis of ventilated disk.

• Journal of the Korea Fashion and Costume Design Association
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• v.2 no.2
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• pp.81-94
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• 2000

This study attempted to make a comparative investigation into architecture and fashion. It was intended to grasp the contemporary meaning of fashion expressed in fashion by investigating the image of lightness expressed in contemporary fashion. With the increasing trend of the characteristics of lightness over the whole field of contemporary design, this study took an opportunity to probe its understanding and a desirable direction of expression. The study results were summarized as follows: First, flexibility conveys comfortableness and lightness that makes people feel wear no costume in a soft and flowing style. This phenomenon is thought to express the desire to depart from the dismal and heavy ideology of the past times. Second, lightness is expressed as the virtual transparency felt from what is spatial. It shows a sense of openness while removing the internal and external boundary. Third, liberalness expresses the unfettered consciousness of freedom by expressing an open, free image through free, thin and transparent fashion.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.367-373
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• 2001

The effect of characteristic of surface roughness and roughness patterns on friction and sliding wear was studied experimentally under reciprocating boundary lubricant sliding conditions. The test was conducted with specimens which have various arithmetic mean value and roughness pattern under the condition of different normal load. The experimental results show that the friction coefficient is decreased because of oxidation mass and valley effect as the normal loads increasing It was found that the specimens with surface roughness with a transverally oriented pattern have a smaller firction coefficient than the other two roughness patterns under the condition of the roughness values of Ra=0.5 and Ra=0.2 .

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.96-99
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• 2001

The fatigue life of support bearings is one of the most critical factors for the performance of a control rod driving mechanism. They are operated at high temperature and high pressure and especially lubricated with dramatically low viscosity water. The support bearing is made of standardized 440C stainless steel, and it supports thrust load including the weight of the driving system and external force. Friction and wear characteristics of this material operating under severe lubrication condition is not well known yet, although it is expected to be changed with respect to temperature and boundary pressure. So the friction characteristics are investigated in sliding conditions using the reciprocating tribometer which can simulate the operating conditions. Highly purified water is used as lubricant, and the water is heated up and pressurized. Friction farce on the reciprocating specimens is monitored by the load cells. The results of the experiments are presented in this paper.

• Journal of the Korean Society of Costume
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• v.54 no.6
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• pp.119-130
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• 2004

The purpose of this study was to analyze the characteristics of 1980s' oversize fashion. Especially in 1980s, there were some characteristics that the leading style did not exist as the other decades, but instead of that, various styles coexisted and the existing traditional rule of fashion was destroyed. On the basis of such background, the moulding nature resident in oversize fashion is considered and analyzed as follows. Firstly, 1980s is the time of power suit booming and through such clothes, women disclosed their consciousness that they want to be equal with men. Secondly, In contrast to that a shoulder pad was the trademark of 1980s' clothes, the social aspect that Japanese designers' clothes of layered look and them of grunge look coexisted is directly expressed through these oversize clothes. Thirdly, In 1980s of the time that people's interest to health risen, sports wear was developed to be everyday wear and furthermore, it had variously influences on high fashion so that developed to big look. Fourthly, when it comes to 1980s' clothes, the atmosphere of society denying apparent boundary between sex at that time was resident in androgynous look and the folklore image of sexless style by their appearance in oversize fashion. What is this situation that the style of the past time is popular in the 21st century even such intentional spirit of challenge already passed？ Maybe for women, the one way of expressing themselves is through their clothes, and for such reason, it can be considered that the social meaning resident in 1980s' clothes is re-examined in the present age.

• Journal of Fashion Business
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• v.21 no.5
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• pp.15-29
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• 2017

The purpose of this study is to examine modern people's lifestyle and identify their needs by analyzing clothing behavior through city nomads' attitudes in dairy life, tastes, and methods to pursue in their life. This study tries to understand substitute values as ethical life emerging recently, free life style of mental emotion, clothing behaviors, and fashion style represented by the results. Upon observing city nomads' fashion trend, tunics symbolizing flexibility and comfort and simultaneously reflect colors in a monk style or from basic items that have been used. City nomads' fashion trend also reveals androgynous freeness-and-easiness. City nomads reflect a folksy inspiration, and different cultural perspectives appear in a mixed fashion. Multi-purpose gypsy/boho style is ideal for traveling and occupying smaller spaces in line with the nomadic lifestyle reflectings an American casual image partially by way of gypsy or bohemian nuances. Motorcycle jeans symbolizing functionality for traveling are becoming a part of everyday life. The fashions discussed are categorized as urban, tourer, sports and road. Everyday sportswear - athleisure - is attracting attention enabling a healthy and sound lifestyle. Athleisure is fashion wear harmonizing workplace with leisure, and everyday life and social gatherings. Athleisure represents a significant collapse of the boundary of high fashion and street fashion. Urban- tech wear is light and enables modern people to perform garment and gear functions simultaneously, making storage useful using various technical devices by elevating activity and functionality. Urban outdoor fashion holding functionality and adding modern fashion in appearance has appeared.