• 한국정밀공학회지
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• 제21권9호
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• pp.41-47
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• 2004

As mechanical structures are minimized, the demand on micro dies and molds has increased. Machining complex 3D shapes requires fabrication procedures for preparing the electrodes. Micro electrical discharge milling using a simple shape electrode can produce 3D micro structure. In this paper the machining characteristics of micro electrical discharge milling according to depth of cut and capacitance are investigated. The machining time is diminished when simple tool-paths and algorithms for changing the feedrate are applied. But a distorted bottom shape and a tapered wall shape are inevitable after machining. The distorted bottom shape and the taper angle of wall are reduced by finish machining.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.392-396
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• 2012

네 가지 핀틀 형상에 대한 정상상태 노즐 유동실험과 유동해석연구를 진행하였다. 실험과 해석결과 핀틀 형상에 따른 추력기 성능변화가 가장 컸으며, 이는 서로 다른 핀틀 형상이 추력기 안에서 움직임에 따라 연소실 압력과 노즐목 면적을 변화시키기 때문이다.

• 소성∙가공
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• 제31권6호
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• pp.394-403
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• 2022

In the automotive industry, cold-drawn austenitic stainless steel is commonly used to handle high fuel pressures in gasoline direct injection (GDI) engines. In this study, we analyzed the effects of main process variables such as cross-sectional shape, drawing speed and friction coefficient on the microstructure, hardness and residual stress of the drawn material in the two-step cold drawing process. By changing the cross-sectional shape in the first-step cold drawing, the possibility of improving the shape accuracy or physical properties of the finally cold-drawn fuel rail pressure sensor product was investigated.

• Coupled systems mechanics
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• 제11권3호
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• pp.267-284
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• 2022

Due to the high usage of ABS in industries, such as aerospace, auto, recreational devices, boat, submarines, etc., the purpose of this project was to find a way to weld this material, which gives advantages, such as affordable, high speed, and good connection quality. In this experimental project, the friction welding method was applied with parameters such as numerical control (NC) machine with two different speeds and three cross-sections, including a flat surface, cone, and step. After the end of the welding process, samples were then applied for both tensile and bending tests of materials, and the results showed that, with increasing the machining velocity Considering of samples, the friction of the surface increased and then caused to increase in the surface temperature. Considering mentioned contents, the melting temperature of composite materials increased. This can give a chance to have a better combination of Nanomaterial to base melted materials. Thus, the result showed that, with increasing the weight percentage (wt %) of Nanomaterials contents, and machining velocity, the mechanical behavior of welded area for all three types of samples were just increased. This enhancement is due to the better melting process on the welded area of different Nano contents; also, the results showed that the shape of the welding area could play a significant role, and by changing the shape, the results also changed drastically.A better shape for the welding process was dedicated to the step surface.

• 한국산림과학회지
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• 제73권1호
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• pp.21-32
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• 1986

단풍나무속(屬) 15수종(樹種)에 대하여 엽병(葉炳) 유관속지(維管束枝) 변화형(變化型)을 해부학적(解剖學的) 방법(方法)에 의해 엽병(葉炳)의 기부(基部)에서 정부(頂部)까지 추적(追跡)하여 분류(分類)하였다. 기본유관속지(基本維管束技)의 수(數)는 3개(個)이나, 복장나무는 3~4개(個)이었다. 유관속(維管束)은 분리(分離), 이동(移動) 및 결합(結合)되며, 분리(分離)되는 수(數)는 11~32개(個)이었고, 결합(結合)되는 수(數)는 0~17개(個)이었다. 분리(分離)와 결합비(結合比)는 0.00~8.00이며, 유관속지(維管束枝) 최대(最大) 수(數)의 절편번호(切片番號)는 39번(番)으로 12수종(樹種)에서 관찰되었고, 신나무와 중국단풍은 절편번호(切片番號) 11번(番), 만주고로쇠와 놀웨이단풍은 13번(番), 은단풍은 26번(番)이었다. 엽병절편(葉炳切片)에서 나타난 최대(最大) 유관속지(維管束枝)의 수(數)는 11~20개(個)이었다. 주유관속지(主維管束枝)에 결합(結合)되는 분지(分技) 수(數)는 0~6개(個)이며, 분리(分離)되는 수(數)는 0~7개(個)이었다. 기본유관속(基本維管束) A, B와 C의 분리(分離) 및 결합비(結合比)는 B기본유관속지(基本維管束枝)를 중심(中心)으로 한 대칭형(對稱型)은 A>BC, AB>C형(型)이 있었으며, 주유관속지(主維管束枝) 형성과정(形成過程)에 의한 분류군(分類群)은 a~g형(型)으로 7가지가 있었다. 특(特)히, 네군도단풍과 은단풍은 중앙유관속지(中央維管束枝)를 가지고 있었으며 그 변화형태(變化形態)도 특이(特異)하였다.

• Tribology and Lubricants
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• 제26권5호
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• pp.297-302
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• 2010

This study is focused on the resin layer formation of UV imprinting process by changing imprinting pressure and period. The mold shape is made for the process of window open over the pattern transfer area and the imprinting period is assigned as the time just before the UV light curing. The residual layer is measured by changing the imprinting period and pressure magnitude, and the measured data of residual layer provides useful information for the design of the process conditions of imprinting processes.

• 한국가구학회지
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• 제22권3호
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• pp.151-159
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• 2011

This study is to suggest versatile chair designs that are organically shaped to take individual orientation. This study intends to provide design method to ensure the face of the chair that contacts the body of its user is transformed flexibly to support the body. The movement of human body is not just a behavior but the ways and tools that reflexively express against external stimuli that are sensed and identified by the person. The versatile chair whose users' sitting position is fixed is made by covering the lump form with a piece of cloth ensuring that the content is firmly fixed and by placing the beads-woven wood fabric according to the shape. And then, it is covered with the external cover. The proposed versatile chair designs assume specific forms as follows: First, it is a versatile chair whose user's sitting position can fix. The organically-shaped form that can accept varying postures is made as a mass, which changes into different shapes when human body touches the form so that users can lie down or sit. Due to such transformation, body posture is determined and individual differences in shape changing are all acceptable. Second, it is a versatile chair that reflects the user's position in a fixed chair, where a cloth-wrapper feature is applied to the form a sifit wrapped postures so that a variety of body postures can be accepted. Finally, a versatile chair that reflects the user's position by changing the shape of is covered with forms so that it will be transformed and used in accordance with situations and chair shapes and reflect multiple shapes including round or square ones.

• 한국수자원학회논문집
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• 제43권4호
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• pp.399-408
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• 2010

본 연구에서는 지형학적 분산을 고려한 특성유속에 따른 Nash 모형 매개변수의 민감도 분석을 실시하였다. 또한 이러한 특성유속의 변동에 따른 순간단위도의 형상의 변화를 수치실험을 통해 비교 분석하였다. 대상유역은 보청천 유역 중 본류에 위치하고 있는 4개의 소유역을 선정하였다. 각 대상유역에 대해 지리정보체계를 이용하여 지표면과 하천의 배수경로길이에 대한 평균과 분산을 산정하였다. 산정된 배수경로길이와 특성유속에 의한 Nash 모형 매개변수를 추정하였다. 추정된 매개변수에 의해 순간단위도를 유도하여 형상의 변화를 비교하였다. 이러한 연구를 통해 도출된 주요 결과는 다음과 같다. Nash 모형 매개변수는 지표면 특성유속에 민감하게 반응함을 알 수 있었다. 또한 순간단위도의 감수부의 형상과 첨두유량은 지표면 특성유속에 지배적인 영향을 받으며, 순간단위도의 상승부의 형상과 첨두시간은 하천 특성유속에 지배적인 영향을 받음을 알 수 있었다.

• 복식문화연구
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• 제17권5호
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• pp.886-896
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• 2009

Acjurumpo is one of the most representatives daily outfit of Joseon Dynasty is a clothes which has a characteristic of having creases under the armhole and it has a lot of chance to use on modern clothes design. This study wants to provide a information on traditional clothes to the public and modernize traditional clothes by designing modern women clothes by adapting Acjurumpo, one of Joseon Dynasty's men' daily outfit which is not very well-known to publics as a link of traditional clothes modernization. Acjurumpo's characteristic is usually having a knife-shape collar and having two sup and one sup, but outside sup of having two sup was more common. There were tongsu, duri, as a example of shape of sleeve. For Mu the combinations were different from Acjurum starting with a shape of trapezoid, triangle to big Mu on a body of side line. For Gorum there were two pairs of long and short Gorum, two pairs of short Gorum or one pair of short or long Gorum. Slit of po was on both side or back. Acjurumpo which was adapted on modern clothes, it was usually used on Hanbok companies that used traditional shape or similar shape to design children' clothes. This study designed three summer one-piece and two winter jacket for women clothes adapting Acjurumpo. And it was designed by using modern material adapting Acjurumpo's characteristics, changing knife-shape collar, Acjurum, mu and Gorum. This study expects for popularization of many traditional clothes developed by modern design in future.

• 한국멀티미디어학회논문지
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• 제20권9호
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• pp.1584-1595
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• 2017

Each cultural community has developed a variety of fonts to express their own language and characters. Hangul has also diversified its font shapes through changing the composition ratio and look of the consonants and vowels. Rather, thanks to the variety of these fonts, a considerable amount of time and effort must be devoted to the selection of a specific font shape. This is related to the fact that the current Hangul service and classification system process the font only with its name or the name of the manufacturer. It means that there is no consensus about the font shape classification system for Hangul. In this study, we propose a shape property set that can be a basis for classifying Hangul fonts. The font shape property set was generated by performing statistical analysis with features which have been studied by the font design experts and was verified through questionnaire using representative fonts based on the classification scheme defined by the Hangul font design classification system standard. This study is meaningful in that it is a study on shape classification properties of K-means and PCA statistical techniques based on font data rather than design field study.