• The Journal of the Acoustical Society of Korea
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• v.18 no.4
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• pp.65-70
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• 1999

To examine the space variances of the sound pressure level for five different types (normal frequency spacing) of reverberation rooms, simulations were conducted using the Finite Element Method. In case of infinite surface impedance, nonrectangular reverberation rooms showed small Standard Deviations across the band of frequency, and in case of finite surface impedance, ideal rectangular reverberation rooms showed the similar results as those in irregular shaped reverberation rooms.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.205-210
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• 2020

The purpose of this study is to propose grading increments chart for women's bodice sloper in their 20s in order to increase consumer satisfaction with apparel products. The selected bodice sloper is a compromise between the German Müller bodice sloper and the Japanese Munhwa bodice sloper. Based on National Standards Position Survey data, the main dimension average for women in their 20s was set. The grading increments was set at the grading deviation application area in bodyboard and sleeve. Thereafter grading was done and the suitability of the graded pattern was checked.

• Korean Journal of Human Ecology
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• v.14 no.1
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• pp.107-117
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• 2005

The purpose of this study is to develop the size and grading increments chart for the middle-aged obese women compared with normal women in middle age. Seven hundred and thirty three women's data from the 4th National Korean Size Survey for Standardization (1997) were analyzed. It was found that size increment of bust and hip girth of obese women was different from that of ordinary middle-aged women. The rate of coverage for a certain set of size specification and the grading increment value for the clothing of Korean obese women in middle aged group were also suggested. The relative percentage value of grading rule based on the change in bust girth increment of Korean obese women was quite different from that of American women. In conclusion, it was noted that the characteristics of the body size specification of obese women was quite different from those of the corresponding age group, so that the separated size specification and grading rule are needed to be used in the manufacturing process of obese women's clothing.

• Proceedings of the Safety Management and Science Conference
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• 2013.11a
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• pp.587-595
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• 2013

기계가공으로 인한 사고는 작업자에게 치명적인 경우가 많다. 이러한 사고는 완벽한 가공지그을 통해 대부분 예방이 가능하지만 제품설계초기 후가공과 양산 공정은 고려되지 않고 설계되어 기계가공 시 재해로 연결되는 경우가 빈번히 발생하고 있다. 사형주조법은 수작업으로 손쉽게 제품을 생산하는 장점을 가지는 반면 치수오차가 다른 양산공정 보다 크다는 단점을 가진다. 이런 사형 주조품을 기계 가공할 때 제품의 치수편차로 인해 불안전한 고정및 과다한 절삭, 제품이탈, 공구파손, 장비와 공구의 빠른 수명감소 등의 다양한 문제가 발생 하지만 사형주조의 특성상 개선하기 어려운 문제로 인식되고 있다. 본 연구에서는 원형의 용기형태의 제품을 사형주조 후 기계가공 하는 것을 금형으로 대체하기 위한 셸몰드법을 제시하고 셸몰드로 만든 셸주형으로 주조함으로서 표면조도 평균 $Ra9.94{\mu}m$의 기계가공에 준하는 표면을 구현하였다. 외형의 정밀한 제품을 대량 생산하여 가공공정의 간소화 및 평균 두께 편차를 줄임으로서 제품파손 및 제작 시 발생할 수 있는 안전사고예방에 긍정적인 영향을 주었다. 기계가공전 제품의 치수정밀도를 높여 안전성, 생산성향상, 가공 공정단축, 환경개선 등을 이 가능함을 확인하였다.

• The Korean Journal of Rheology
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• v.9 no.2
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• pp.66-72
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• 1997

사출성형품의 품질특성으로 외관, 치수, 기계적 강도 등이 있으나 조립부품으로써 사 될경우에는 치수가 주요한 품질이 된다. 성형품은 용융수지의 특성상 사출공정 중 수축을 일으키므로 이를 고려해서 금형설계가 이루어지지만 실제 사출과정에서 공정변수를 최적화 하여 관리하지 않으면 허용오차 내의 치수를 얻기가 힘들다. 본 논문에서는 주요조립부의 치수가 허용오차 내에서 얻어지도록 설계시 적용된 수축률과 측정된 수축률의 차이를 목적 함수로 하여 최소화 시키며 반복이차계획 알고리즘을 채택한 IDESIGN 프로그램을 이용해 최적 사출성형조건을 구하였다. 제약조건은 성형품의 부위별 수축률 편차 및 싱크마크 깊이 가 공정변수의 부등호 제약식으로 도출되었고 성형이 이루어지는 공정변수의 상하한 값이 최대 및 최소 경계값으로 적용되었다.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.6
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• pp.999-1011
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• 2008

To most of the students studying fashion related major, the graduation fashion show is a big challenge. They have to put together all they learn and show what they can do to their future employers. They design, pattern work, and make up garments for the show all by themselves. Unfortunately. while they make up their garments, they usually don't Dow exactly body measurements of the models. So quite often they have to alter their art works up to the last minute of the fashion show opening. Sometimes such unadequate work process ruins their work. The purpose of this study is to suggest block patterns of Korean fashion models measurements for basic items, such as jacket and pants for male models and torso length block pattern, skirt and pants for female models. 20 male and 20 female professional models were measured. The block patterns were based on their measurements. After the first fitting test, patterns were corrected by their body characteristic. For both male and female models, it was found desirable to fix the shoulder width and make an adjustment to the patterns with a deviation of width and girth items. In case of the resultant patterns the satisfaction was made better. Model sizes proposed in this study are considered closer to the size of average models, since they were based on A-grade models who are currently working in Korea. The resultant patterns can be produced by simply making a slight adjustment to the width of the proposed pattern in this study.

• Polymer(Korea)
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• v.32 no.6
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• pp.501-508
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• 2008

Small injection molded articles such as lens and mobile product parts are usually molded in multi-cavity mold. The problem occurring in multi-cavity molding is flow unbalance among the cavities. The flow unbalance affects the dimensions and physical properties of molded articles. First of all, the origin of flow unbalance is geometrical unbalance of the delivery system. However, even the geometry of the delivery system is well balanced, cavity unbalance occurs. This comes from the temperature distributions in the cross-section of runner. Temperature distribution depends upon injection speed because heat generation near runner wall is high at high injection speed. Among the operational conditions, injection speed is the most significant process variable affecting the filling unbalances in multi-cavity injection molding. In this study, experimental study of flow unbalance has been conducted for various injection speeds and materials. Also, the filling unbalances were compared with CAE results. The dimensions and weights of multi-cavity molded parts were examined. The results showed that the filling unbalances vary according to the injection speeds and resins. Subsequently, the unbalanced filling and pressure distribution in the multi-cavity affect the dimensions and physical states of molded parts.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.172-176
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• 2003

In this paper, we studied the effects of mold temperature on the microstructure of injection molded parts. The weld line decreases in length and width as mold temperature increases. We investigated the dimensional stability of the parts made of two kinds of resin(polypropylene and polystyrene) by varying the mold temperature. As the mold temperature is high, both the shrinkage ratio and the thickness difference for the PS parts decreases. But the observation of PP parts shows a tendency to increase. The easiness of cavity filling and transcription of the mold texture is improved as the mold temperature is high.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.418-418
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• 2015

산업화로 인하여 지구온난화가 가속화됨에 따라 전 세계적으로 경험하지 못한 자연재해가 발생하고 있다. 한반도 역시 집중호우와 같은 극치수문사상으로 인해 매년 막대한 인명 및 재산피해가 발생하고 있다. 2010년 9월 21일 발생한 호우는 상대적으로 지역적인 편차가 큰 국지성 집중호우 형태로 인하여 국가기관시설이 밀집한 종로구 광화문 일대에 내수침수를 야기한바 있으며, 2011년 7월 26일 이후에 발생한 집중호우의 경우 연 강수량의 30% ~ 45%를 차지할 만큼의 많은 양의 비가 내리면서 우면산 산사태, 강남역 및 도림천 침수를 발생시킨 바 있다. 특히, 치수대책을 고려하지 않은 무분별한 도시개발과 여름철의 강우 집중화(연강우량의 약 70%) 때문에 수자원확보 및 수방대책에 어려움을 겪고 있는 실정이다. 보다 효율적인 이 치수 대책을 위해서는 한반도에 영향을 미치는 집중호우에 대한 정량적인 분석이 수행되어야 한다. 따라서 본 연구에서는 호우분리기법을 적용하여 집중호우만을 추출하고 한반도 집중호우의 극치사상을 시공간적인 특성 및 변동 및 경향 분석을 수행하고자 한다. 본 연구의 결과는 향후, 이 치수 대책을 고려한 도시계획 및 대책 수립에 대한 기초자료로 활용 가능 할 것으로 판단된다.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.5
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• pp.839-852
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• 2023

This study examined personal protective clothing, specifically the D (M, L, XL) and C (L, XL, 2XL) levels with high sales rates. The goal was to collect essential data for developing Korean personal protective clothing. There were eight and twelve patterns for the D-level and C-level, respectively. While the pattern dimensions were similar, the chest and waist circumferences (relaxed) were larger in the C-level, and the waist (extended), hip, upper arm circumference, and total lengths were larger in the D-level. The D-level wear sensation worked well for average-sized Koreans in their twenties, but the C-level caused discomfort in multiple areas, such as the face, arms, armpits, hips, crotch, thighs, and knee during movement. Consequently, this region required pattern adjustments and resetting for improved comfort. The grading rules were 10 cm in the chest, waist, and hip circumference, regardless of the level, with slight differences in other parts depending on the levels. Thus, manufacturers should establish new grading rules to suit the Korean body shape.