• 대한기계학회논문집
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• 제19권7호
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• pp.1619-1629
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• 1995

The Al/Al$_{2}$O$_{3}$ SiC and Al/Al$_{2}$O$_{3}$/C hybrid metal matrix composites (MMCs) were fabricated by squeeze infiltration method. Uniform distribution of reinforcements were found in the microstructure of metal matrix composites. Mechanical tests were carried out under various test conditions to clearly identify mechanical behavior of MMCs, and the wear mechanism of Al/Al$_{2}$O$_{3}$/(SiC or C) hybrid metal matrix composites were investigated. The tensile strength and hardness of hybrid composites was resulted in increasing compared with those of the unreinforced matrix alloy. Wear resistance was strongly dependent upon kinds of fiber, volume fraction and sliding speed. The wear resistance of metal matrix composites was remarkably improved by the addition of reinforcements. Especially, the wear resistance of the hybrid composites of carbon fibers was more effective than in the composites reinforced with alumina and SiC whiskers of reinforcements. This was due to the effect of carbon fiber on the solid lubrication. Wear mechanisms of hybrid composites were suggested from wear surface analyses. The major wear mechanism of hybrid composites was the abrasive wear at low to intermediate sliding speed, and the melting wear at intermediate to high sliding speed.

• 복식문화연구
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• 제17권2호
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• pp.352-366
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• 2009

The purpose of this study was to investigate the actual wearing conditions and the preferences of knit wear school uniforms. The subjects were 480 high school girls from 6 high schools placed in Daejeon. The method of study is a survey consisted of actual wearing conditions questionnaires, preferences questionnaires, and demographic attribution. Data was analyzed by frequency, variance, crosstabs, and correlation analysis using SPSS 12.0 program. The results of study are as follows. First, high school girls over 90% wearing knit wear school uniforms were satisfied with current knit wear school uniforms(navy color, V-neck, and wool mixed). Second, high school girls preferred 100% cotton material and black/white/gray color group. The style of knit wear school uniforms was most preferred monochrome cardigan with cable pattern. High school girls wanted to show neat image by knit wear school uniforms and to diversify the style of them. Third, the differences of preferences between groups, they were wearing knit wear school uniforms(A group) or not(B group), were about pattern and improvement. A group preferred school mark pattern, and wanted to improve the quality and after service. B group preferred monochrome cable pattern, and wanted to diversify the style. Both groups wanted to wear knit wear school uniforms because knit wear was 'warm' and 'comfort'. Consequently, knit wear school uniforms will help high school girls express individuality and beauty.

• 한국재료학회지
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• 제15권12호
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• pp.824-828
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• 2005

In this study the effect of the content of $TiB_2$ on wear properties was investigated. $Cu-TiB_2$ composites have been fabricated by hot extrusion. Sliding wear tests were peformed by a pin-on-disk type wear test machine under dry condition and loads varied with from 20N to 80N at sliding speed 3.5Hz. The test results showed that the wear losses and the friction coefficients decreased with increasing $Cu-TiB_2$ volume fraction and increasing the size of $Cu-TiB_2$ particle. Wear property of $10{\mu}m,\;5 vol\%\; TiB_2$ specimen was excellent all of the wear specimens. It is thought that the increase of plastic flow resistivity due to uniform distribution of $10{\mu}m,\;5 vol\%\; TiB_2$ wear specimen would improve wear property. The worn surface and wear debris were examined by optical microscope and scanning electron microscope.

• 대한기계학회논문집
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• 제10권2호
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• pp.223-231
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• 1986

본 연구에서는 공구현미경을 이용하여 간판하게 공구수명을 구할 수 있는 방법을 제시하기 위한 전 단계로서 공구의 마멸거동에 대하여 연구하였다. 공구의 마멸은 매우 복잡한 현상이며 대부분의 경우 주로 마멸의 누증이 공구를 파손에 이르 게 한다. 마멸의 형태중 마멸(abrasion wear)과 점착에 의하여 발생되는 측면마멸이 가공물의 표면조도, 정밀도 및 절삭동력에 미치는 영향과 측정상의 경의 때문에 공구 수명을 지배하는 주마멸인자로 취급되고 있다. 따라서 절삭시간에 대한 공구의 측면 마멸 거동을 분석하여 초경공구의 측면마멸유선의 직선모델을 구하고, 측면마멸유선의 일반모델을 확립하였다.

• 한국의상디자인학회지
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• 제23권1호
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• pp.143-154
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• 2021

This study attempted to develop winter jackets and pants patterns reflecting the latest comfortable and active school uniform trends, using middle school boy avatars having various body shapes. Jacket and pants pattern-drawing methods and margins differed. Based on the results, research prototypes were prepared. Then, virtual wear prospective drawings, clothing pressure, and appearance were assessed according to body shape. Jackets were assessed using 25 factors, while pants were assessed using 19. Then, correlations between the jackets and pants were analyzed. According to the analysis, the reason why the dart & tuck position and margin were rated low was confirmed. In a virtual wear assessment on jacket patterns by body shape, a significant difference was found in all categories, except for fit and shape at the front bottom, sleeve length on the side, and the center back line. The virtual wear assessment on the pants patterns by body shape also revealed a significant difference in all categories, except for pants length. In jackets, a significant influence was observed around the shoulders and waist in Type 1 and around the belly in Type 2. On the contrary, for pants, a significant influence was found around the hip and waist in Type 1 and around back crotch in Type 2. Therefore, they should be considered when making of jackets and pants. The above results suggested that jacket and pants patterns should vary depending on body shape. It is anticipated that there should be further studies comparing brand-name school uniforms for middle school girls and school uniforms by body shape.

• 한국의류학회지
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• 제26권1호
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• pp.168-178
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• 2002

This study is aimed at investigating and comparing the differences in the uniform of nurses according to regions and hospital size in Korea. This study takes two large regions as its survey area; one is Seoul, Incheon and Gyeonggi Province, and the other is Daejon and Chungcheong Province. The hospital size is divided into general hospitals and neighborhood hospitals. The survey was conducted among the nurses working in 12 randomly-selected hospitals and its statistical results are analysed firm 818 respondents'questionnaires. The results are divided into 3 categories as follows; 1) Results of analysis of survey on the uniform of nurses : Nurses usually wear two-piece suits and more than half of the hospitals choose a white-color pattern. And the nurse's uniform with color varying according to their position and ward is considered to be desirable; 2) Analysis on regional differences : In the case of Daejon and Chungcheong Province, there is a relatively high ratio of respondents who answered questions with 'high percentage of young nurses', 'position differentiation by means of different design and fabric according to ward'. In case of Seoul, Incheon and Gyeonggi Province, questions with 'use of a patterned textile in nurses'uniform', 'ready-made size system'are higher; 3) Analysis of the differences in accordance with hospital size : In the case of general hospitals, there is relatively a high ratio of respondents who answered questions with 'use of different design and fabric according to a nurse's position', 'use of patterns in nurses'uniform'. In the case of neighborhood hospitals, there is a high ratio of respondents with'use of classical one-piece or two-piece type wear', 'ready-made type size system', 'obligatory use off nurse's cap'.

• 대한가정학회지
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• 제37권11호
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• pp.75-83
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• 1999

To develope an efficient fire fighter’s uniform for the fire fighting work and body protection, this study examined the regulations of fire lighter’s uniform and surveyed the actual wearing conditions, satisfaction degree, preferred color and design others. The results are as follows; 1. As for the satisfaction degree, the degree was normal in ordinary, low in working uniform and heat-proof uniform and very low in water-proof uniform about its design, size, color and materials. 2. As for the color, red was preferred for the working uniform and water-proof uniform. Blue, yellow and green was preferred next for corking uniform and yellow and blue for water-proof uniform. 3. As for the design, fire fighters wanted partial revision of the present uniform. They preferred stretchy training wear style and overact style in order. For the water-proof uniform, they preferred hip-length suit and pants and next to it they liked flee-length suit, waist belt and overact in order. 4. As for the regulations of the uniform, they wanted some addition in casual uniform, water-proof pants and water-proof gloves, and some deletion in the thermal barrier of water-proof uniform and ordinary uniform. 5. As for the distribution of the uniforms, the use of coupons was highly preferred.

• 한국생활과학회지
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• 제17권2호
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• pp.345-353
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• 2008

This survey intends to understand the opinion and status on preschool students' uniform wearing for the purpose of new style development. The results from this study will serve as an activator of related industry. The merit of uniform wearing in these students was recognized primarily as: (1) students can have pride in the schools they attend; (2) they need not worry about clothes to wear every morning. The disadvantage of uniform wearing derives from: (1) students' personality is hardly expressed by uniforms; (2) difficulty in uniform selection suitable for varying weather conditions. This disadvantage felt by their parents suggests the lack of personality expression and appropriate body temperature control. The most prevalent opinion for preference and future improvement points was the consideration of physical activity in children. This indicates that they prefer uniforms rendering minimal restriction on body movements. Other Improvement points stress the activity, uniform laundering and care, convenience in on and off, insulation, colors, design and durability.

• 한국의류학회지
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• 제26권5호
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• pp.654-662
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• 2002

The aim of this paper was to identify high school girls'satisfaction toward Korean traditional style school uniform and their clothing behaviour. The questionnaires were administered to 133 high school girl students in Pusan. To find out attitudes of Korean traditional style school uniform and their clothing behaviour, PC model, mineigen and Varimax Rotation of factor analysis were adopted. The results have shown that each four factors are identified in Korean traditional style school uniform's satisfaction and their clothing behaviour. Multiple Regression analysis has been used to investigate the relationship between these factors of attitudes and satisfaction toward Korean traditional style oriented school uniform. As a result, the relationship between factors of their school uniform behaviour and satisfaction of their school uniform has revealed. They tend to wear their school uniform in various occasions if their satisfaction becomes greater. Besides, the more students have recognized the uniform as symbol of status the more they become satisfied with their school uniform. The relationship between factors of clothing attitudes and satisfaction of school uniform has shown that its uniform doesn't promote students conformity since they might be aware of different style and design of their school uniform compared to other school uniforms.

• Journal of Mechanical Science and Technology
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• 제15권11호
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• pp.1524-1532
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• 2001

The effects of recirculated exhaust gas on the wear of cylinder liner and piston were experimentally investigated by a two-cylinder, four cycle, indirect injection diesel engine operating at 75% lo ad and 1600 rpm. For the purpose of comparison between the wear rates of the two cylinders with and without EGR, the recirculated exhaust gas was sucked into one of two cylinders after the soot in exhaust emissions was removed by an intentionally designed cylinder-type scrubber equipped with 6 water injectors(A water injector has 144 nozzles of 1.0 mm diameter), while only the fresh air was inhaled into the other cylinder. These experiments were carried out with the fuel injection timing fixed at 15.3$^{\circ}$ BTDC. It was found that the mean wear rate of cylinder liner with EGR was greater in the measurement positions of the second half than those of the first half, that the mean wear rate without EGR was almost uniform regardless of measurement positions, and that the wear rate of piston skirt with EGR increased a little bit, but the piston head diameter increased, rather than decreased, owing to soot adhesion and erosion wear, and especially larger with EGR.