• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1445-1449
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• 2005

The ram assembly is important equipment in fueling machine of PHWR(Pressurized Heavy Water Reactor) plant where fuel replacement is possible while the plant is in service. Troubles in the ram assembly can cause lots of difficulties in power plant operation. The ram assembly is typically composed of the B-ram, the L-Ram and the C-Ram. The B-ram is focused in this paper because it plays the most important role in the ram assembly. Among the ram fault phenomena, ram stuck phenomena are the most frequent cases in the B-ram, which has a ball screw mechanism driven by a hydraulic motor. Ram stuck phenomena are due to ball wear and damage in ball nut that increase in proportion to the number of fuel replacement. It is required to predict ram stuck phenomena before they occur. In this paper, a method is proposed for predicting ram stuck phenomena using a discrete wavelet transform. The discrete wavelet transform provides information on both the time and frequency characteristics of the input signals. The proposed method uses the frequency bandwidths of coefficients of discrete wavelet decompositions and detail coefficients of discrete wavelet transform to predict ram stuck phenomena. The signal used in this paper is a torque-related signal such as a hydraulic service outlet pressure signal in a hydraulic driving system or a current signal in a DC motor driving system. Finally, the validity of the proposed method is shown via experiment using ball nut characteristic test equipment that simulates ram stuck phenomena due to increased ball friction in ball nut.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권2호
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• pp.136-142
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• 2006

Temporomandibular joint(TMJ) disorders have characteristic clinical findings such as pain, joint sound, and abnormal jaw function. With the rapid progress in TMJ imaging techniques, magnetic resonance imaging(MRI) especially provides the clinician and researcher with the ability to evaluate TMJ disorders(effusion, anterior disk displacement) and the hard and soft tissue of the TMJ. In order to manage the internal derangement of TMJ such as anterior disk displacement, the so-called appliance therapy is commonly used. This technique became the treatment of choice before surgical intervention by many practitioners. The purpose of the present study was to evaluate and determine the efficacy of anterior repositioning splint by means of the change of the position of the disk through pre- and post-treatment MRI. MRI and clinical symptom were carefully recorded in TMJ disorder patients. The relationship between TMJ symptoms such as pain, clicking sound, and disk displacement and effusion in MRI were analyzed. Then, splint therapy was applied for 3 months according to our protocol; at day 1, patients should wear 24 hours, in order to accomodate the splint and then, wearing time is reduced to 12 hours per day for one month. During next 2 months, it is tapered to 8 hours per day according to the evaluation of the clinical symptoms. Post-treatment MRI was obtained after 3 month protocol. This treatment strategy improved the clinical symptoms of TMJ disorder, and effusion and articular disk position showed a significant change. In conclusion, a treatment modality using an anterior repositioning splint therapy is an appropriate method for temporomandibular disorder patients.

• 복식문화연구
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• 제6권1호
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• pp.136-148
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• 1998

This is a study on the change of the Medievalmen's underclothes. Underclothing includes all such articles, worn by either sex, as were completely or mainly concealed from the spectator by the external costume. Throughout the Middle Ages, the underclothing of both sexes possessed characteristic inherited from earlier times. Its function was purely utilitarian. It was not used to express class distinction and only very indirectly to enhance sex attraction. The idea of underclothes was associated with the idea of the body's sinfulness. Underclothes could also symbolize the discipline of humility. To appear clad only in underclothes was a voluntary form of selfabasement often practised by pilgrims. The notion that underclothes might express the spirit of the changing times, in sympathy with the outer clothing, did not enter the medieval mind. The length of the shirt was less than that of the modern garment, especially after the middle of the fourteenth century. The sleeves were somewhat full, without cuffs, and cut straight. During the second half of the twelfth century, when braies become definitely an undergarment. In the fourteenth century braies became shorter and shorter and the shirt could no longer be tucked in but hung outside over the thighs. After 1340 the costume on the surface somewhat resembling modern 'tights', began to reveal display the shape of the male leg as a form of sex attraction. By the close of the Middle Ages, braies had become less like loincloths, and more like modern bathing trunks. The peasant and laborer did not attempt to keep pace with the changes of fashion but, continued, as a rule, to wear the long braies of their forefathers. The higher ranks how this garment reflected the changes of the mode of outer costumes.

• 대한기계학회논문집A
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• 제35권5호
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• pp.555-559
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• 2011

본 연구는 유압 피스톤 펌프 재료로 사용되고 있는 SACM645소재를 사용하여 모재, QT(quenching & tempering) 시험편 및 QT 질화시험편의 피로특성을 조사하였다. 피로특성 조사결과는 다음과 같다. QT 질화시험편은 피로한도가 인장강도의 80%로 나타나 아주 높은 값을 나타내었다. 이것은 시험편 표면에 단단한 질화처리를 실시하여 피로균열의 발생을 지연시켰고, 피로균열이 발생하더라고 소재가 단단하여 균열진전속도가 늦었다고 판단된다. 파면 관찰결과 피로균열진전 영역에서는 모두 스트라이에이션이 관찰되었고, 피로균열진전 이외의 영역에서 QT 시험편은 벽개파괴의 양상을, 모재와 Qt 질화시험편은 딤플 파괴의 양상을 나타내었다.

• 복식
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• 제62권6호
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• pp.165-181
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• 2012

Alexander McQueen is a typical designer of unconventional and experimental design who showed maximalism through outstanding tailoring. The purpose of this research is to study formative characteristics of maximalism that are expressed in modern fashion based on the works of Alexander McQueen, and to suggest boundless possibilities of development through his sense of design and the expressive ability of his works. Theoretical considerations will be made through literature research and precedent studies, and the collection data for case analysis will be used to select ready-to-wear women's collections from 2001 S/S to 2010 F/W by referring to internet sites. The study results are as follows. First, the most representative characteristic of formative characteristics of maximalism expressed in Alexander McQueen's works is expandability. Second, decorations used as a part of detail on clothes is used as decoration itself, and handcraft expression is shown through excessive use of decorations. The expandability of decoration that emphasizes splendid magnificence is expressed through flawless technique. Third, the fusion of each different image and the combination of ethnic image and modern image was most prevalent. Fourth, fantasy expresses a fictive image that could not be seen in reality by expressing an unrealistic and maximized image through the imagination of designer. Fifth, experimental element is expressed as an image that actively reflects the challenging spirit, which suggests a new direction of beauty through shocking and extraordinary images of the inner world of the designer and the root of new ideas about inhumane modern society.

• 복식문화연구
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• 제13권5호
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• pp.790-803
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• 2005

This study purposes to examine the background of the sexual concept and femininity, masculinity and gender role in the fields of social psychology and cultural anthropology and investigate the traditional gender role and the fashion's changes according to its role and the examples of the masculinity and femininity expressed in the contemporary fashion and finally analyze the gender identity expressed in fashion. The image changes which appeared in the modern fashion can be considered to be Masculine Look, Garconne Look, Feminine Look, Unisex Look, Androgynous Look and Genderless Look. The Garconne Look caused lots of changes to masculinity in the 1920's along with the changes of femininity. With the effect of feminism, many females wore clothing which had been thought as male's clothing by the appearance of Masculine Look. The major formation reason of Unisex Look can be regarded as the attitude change of the society toward to females and a meaning which doesn't want the differences of the distinction of gender to appear any longer as a characteristic external factor is implied. Androgynous Look which appeared in the 1980's means the integration of femininity and masculinity which is the same meaning with 'androgyny' in itself, Not denying its gender characteristics individually, the Androgynous Look means that women aim at the masculine image in men's clothing or men do at the feminine image in women's clothing. Genderless Look can be considered to a look with a notion to wear clothing freely even in fashion transcending the border of masculinity and femininity differentiated socially and culturally.

• 복식문화연구
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• 제28권3호
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• pp.356-375
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• 2020

The purpose of this study is to understand the characteristics and cultural values of the headdress among Chinese minorities with diverse ethnic cultures, and to provide various data on the design of clothing accessories. Theoretical considerations about ethnic minorities were addressed through literature and prior research, with data being collected using literature and websites. The results are as follows. First, the most common type of headdress is the horizontal type, which includes the head style, headband, and head scarf. The second most common is the cylinder type, which is a headdress with variations in the shape of a round hat, and has is evident among various minorities. Third, the pagoda type is decorated with ornaments mounted on top of a round shape. Fourth, the square crown type is a piece of wood as a material for a form of the material and for a variety of jewelry and the production of up to meet the women's head of the jewelry. Fifth, head belt-type ornaments consist of a headband and fancy bead ornaments from the bottom of the head. Mongol women usually wear an exaggerated form of this type. Sixth, the head cover type is a head decoration influenced by the dress code of Muslim women. Seventh is the disc type of crown shape worn by the Dai. Next, the ogival type is a cone-shaped headdress hat most commonly seen as head ornament hat among the Dai. Lastly, the sailboat type is the most exaggerated form of hair ornaments found among ethnic minorities.

• 한국자동차공학회논문집
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• 제18권2호
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• pp.83-90
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• 2010

The windshield wiper consists of 4 parts: a blade, an arm, a linkage and a motor. The wiper blade makes contact with the windshield and is designed to be operated normally at an angle of 30~50 degrees to the front glass. If the contact pressure between the wiper blade and windshield surface is too high, noise and wear of the rubber will result. On the other hand, if the contact pressure is too low, the performance will do badly, since foreign substances such as dust and stains will not be removed well. The pressure and friction of the wiper blade has a great influence on its effectiveness in cleaning the front window. This is due to the contact of the rubber with the window. This paper presents the dynamic analysis method to estimate the performance of the flat type blade of the wiper system. The blade has a nonlinear characteristic since the rubber is an incompressible hyper-elastic and visco-elastic material. Thus, Structural dynamic analysis using a complex contact model for the blade is performed to find the characteristics of the blade. The flexible multi-body dynamic model is verified by the comparison between test and analysis result. Also, the optimization using the central composite design table is performed.

• 대한기계학회논문집A
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• 제37권3호
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• pp.373-378
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• 2013

엔진의 출력증대와 이에 따른 변속기의 크기 증가 등으로 인한 회전체의 관성증가로 변속기의 변속성능은 악조건이 되고 있다. 따라서, 이를 해결하기 위하여 내마모성이 높은 마찰소재의 개발이 요구된다. 디젤차량 수동변속기용 싱크로나이저 링에 요구되는 마찰특성에 적합한 소재를 개발하고, 이에 대한 접합 특성을 평가하였다. 즉, 철합금 모재와 동합금계 마찰재를 접합하는 공정을 개발하고, 접합층에 대하여 BSE분석, EDX분석을 수행하여 접합특성을 평가하였으며, 해당 시험편에 대하여 전단강도를 평가하였다.

• 한국정밀공학회지
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• 제15권10호
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• pp.65-72
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• 1998

The BTA drilling chip is better for deep hole drilling than other self-piloting with pad drilling chips because the large length to diameter ratio allows a unique cutting force dispersion and better supplies the high pressure fluid. Therefore the BTA is useful for many tasks, such as coolant hole drilling of large scale dies, as well as tube seat drilling, which is essential for the heat exchanger, and variable component drilling for automobiles. Deep hole drilling has several significant problems, such as hole deviation, hole over-size, circularity, straightness, and surface roughness. The reasons for these problems, which often result in quality short comings, are an alignment of the BTA drilling system and the unbalance of cutting force by work piece and tool shape. This paper analyzes the properties through an experiment which com¬pared single-edge BTA drills with multiple-edge BTA drills, as well as the shapes of the tools to cause an unbalance of cutting force, and its effect on the precision of the worked hole. Conclusions are as follows. 1) In SMSSC drilling, 60m/min of BTA with single and multi-edged tools proved the best cutting condition and the lowest wear character. 2) The roundness got a little worse as cutting speed was increased, but surface roughness was hot affected. 3) It was proved that the burnishing torque of both drills approached 26%. which is almost the same as the 24% insisted on by Griffiths, and the dispersion characteristic of the multi-edged BTA drill proved better than the single-edge BTA drill.