• 대한기계학회논문집B
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• 제34권3호
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• pp.291-299
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• 2010

본 연구에서는 열의 수가 세 개인 원형관 및 종횡비가 고려된 납작관-평판휜 형상의 밀집형 열교환기 내 공기의 유동 및 열전달 특성을 RNG $k-{\varepsilon}$ 난류모델을 적용하여 수치적으로 해석하였다. 수치조건의 범위는 원형관인 경우 1,000<$Re_D_h$<10,000이며, 납작관인 경우 1,000<$Re_{D_h}$<10,000 및 3.06$f\;=\;CRe^m_{D_h}$의 형태로, Colburn j 계수는 $j\;=\;CRe^m_{D_h}$ 형태로 상관관계식을 제시하였다. 이러한 상관관계식은 향후 원형관 및 납작관-평판휜 형상의 열교환기 설계시에 기본적인 자료로 충분히 활용될 수 있을 것으로 판단된다.

• 설비공학논문집
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• 제13권5호
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• pp.398-410
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• 2001

The flow and heat transfer characteristics for three-dimensional mixed convection flows in a radiator flat tube with U--shaped grooves are analyzed numerically. The flow and temperature fields are calculated by using the modified SIMPLE algorithm for irregular geometry. One tube specification among the various flat tube exchangers is recommended by considering the heat transfer and pressure drop. The effects of variation of coolant flow conditions and external air conditions on the flow and the thermal characteristics for the selected tube are investigated. the results show that inlet velocity of coolant flow is the very important factor in heat transfer and pressure drop, and top side is better position than the others as fin cleave to tube.

• 한국축산시설환경학회지
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• 제16권2호
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• pp.123-128
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• 2010

비닐하우스용 소형 액비살포기를 설계, 제작하였으며, 납작호스용 일체형과 견고한 둥근호스 분리형으로 되어 있다. 살포장치의 구성은 권취기, 유압모터, 유압실린더, 배출장치, 호스, 3점링크히치, 호스고정장치, 프레임 등으로 되어있다. 살포 시스템은 일체형과 분리형으로 나누어진다. 일반적으로 납작호스는 일체형에 사용되고 둥근호스는 분리형에 사용된다. 분리형은 좁은 공간에서 선회 등을 할 때 작업의 활동성을 개선할 수 있다. 액비살포기를 사용함으로써 작업효율을 5배 정도 높일 수 있었으며, 인력소요는 1/3로 감소되었다. 원하는 살포량에 따른 작업속도를 맞추어주면 면적당 목표 살포량을 얻을 수 있다. 관리자에 대한 작업환경이 개선되었다.

• 대한기계학회논문집B
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• 제33권5호
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• pp.318-325
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• 2009

Numerical analysis has been carried out to investigate air-side convective heat transfer characteristics in compact heat exchanger with flat tubes and continuous plate fins having a symmetric and non-symm etric staggered arrangements. Simulation results such as air velocity and temperature distributions are presented, and heat transfer coefficients are compared with previous experimental results. In order to investigate the flow and heat transfer features by periodic boundary conditions, the three blocks were used. Predicted heat transfer coefficients between the three blocks are similar while there are relatively differences, compared with the experimental data. From the calculated results a correlation for Colburn j factor in the compact heat exchanger system is suggested. The predicted results in this study can be applied to the optimal design of air conditioning system.

• 대한기계학회논문집B
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• 제32권9호
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• pp.695-703
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• 2008

Numerical analysis has been carried out to investigate air-side convective heat transfer characteristics in a compact heat exchanger with flat tubes and continuous plate fins according to the aspect ratio. RNG k-$\varepsilon$ model is applied for turbulence analysis. Simulation results such as air velocity and temperature distributions are presented, and heat transfer coefficients are compared with previous correlations for circular tubes. The numerical conditions are considered for the aspect ratios ranging from 3.06 to 5.44 and Reynolds number ranging from 1000 to 10,000. The results showed that heat transfer coefficients decreased with the increase of aspect ratio. From the calculated results a correlation of Colburn j factor for the considered aspect ratio in the compact heat exchanger system is suggested. The predicted results in this study can be applied to the optimal design of air conditioning system.

• 박물관보존과학
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• 제30권
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• pp.71-88
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• 2023

조선시대 유리구슬의 가시적 특성과 화학 조성을 알아보고 그에 따른 연관성을 알아보았다. 또한 권역에 따른 특성에 대하여 고찰하였다. 연구 대상은 경기, 충청, 경상권역 25개소에서 출토된 1,819점으로 이 중에서 화학 조성 분석은 537점을 실시하였다. 조선시대 유리구슬은 크게 둥근형, 코일형, 꽃잎형, 연주형, 납작형, 대추형과 표주박형 구슬 등의 형태가 나타난다. 색상은 크게 갈색계(갈색, 담황색), 청색계(청록색, 벽색, 감청색), 백색계(무색, 백색), 녹색계(녹색, 녹청색, 녹갈색) 등이 나타난다. 갈색이 가장 많은 수량을 차지하고 다음으로 청록색과 벽색이 주로 확인된다. 조선시대 유리구슬 제작기법은 대표적으로 말은 기법이 확인된다. 유리구슬의 융제는 주로 K₂O가 사용되었고, 포타쉬유리군, 알칼리혼합유리군 등이 가장 많은 수량을 차지한다. 안정제는 융제의 종류에 따라 다르긴 하나 주로 CaO와 Al₂O₃가 사용되었다. 포타쉬유리군과 포타쉬납유리군은 HCLA계, 알칼리혼합유리군은 HCA계. 이와 반대로 납유리군은 LCA계에 속한다. 색상과 형태의 연관성으로 갈색계와 청색계는 둥근형이 가장 많으며 청색계는 코일형이 두드러지게 나타난다. 녹색계와 무색계도 코일의 비중이 높고 백색은 꽃잎형의 비중이 높다. 형태와 화학 조성에 대한 연관성으로 둥근형, 꽃잎형, 연주형은 포타쉬유리군이, 코일형과 납작형은 알칼리혼합유리군의 수량이 많다. 색상과 화학조성의 연관성으로 각 색상의 착색제에 대하여 알아보았다. 갈색과 백색은 Fe, 담황색은 Ti, Fe가 착색제로 작용하였다. 감청색은 Co가, 벽색과 청록색, 녹색, 녹청색은 Fe와 Cu가 작용하였으며, 무색은 착색제의 성분함량이 대체적으로 낮은 편이다.

• 한국의상디자인학회지
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• 제5권1호
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• pp.59-71
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• 2003

The purpose of this study is to provide for the basic data useful to the development of a quality brassiere featuring a good wearing feeling and an effect of reinstating and correcting breast shape. For this purpose, 220 adult women aged between 20 and 59 were sampled to survey their perceived and actual breast shapes. The results of this study can be summarized as follows; 1. Most adult women correctly perceive the changes of their breast shapes as they become older. However, the younger women tend to evaluate their breast as larger than their actual sizes, being more dissatisfied with their breast shapes than older women, while wanting their constitution to be more high and slim. In short, there is a little difference between their perceived and actual breast shapes. 2. The breast shape perceived most by the adult women is "droopy type I"(37.7%), followed by "conical type"(21.8%), "flat type"(16.8%), "semi-circular"(10.8%), "droopy type II"(8.6%) and "extruded type"(5.0%) in their order. The younger women tend to perceive their breasts as "flat", "conical" or "semi-circular", while the older women tend to perceive their breasts as "droopy". 3. According to the increase of age, the items of height were decreased and items of width, depth, circumference and length were increased, being obser and breast point were drooped. so volume and bottom area of breast of 40ㆍ50's women's age group were larger than 20?30's women's age group and breast point width of 40ㆍ50's women was being wider by increase of interior dimensions of breast.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1443-1448
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• 2009

Numerical analysis has been carried out to investigate air-side convective heat transfer characteristics in compact heat exchangers with continuous plate fins. Simulation results such as air flow and temperature distributions are presented, and heat transfer characteristics are compared for various inlet conditions. Results from various turbulence models are also compared for applicability. There is large difference between the local heat transfer coefficient distributions along the cylinder wall for circular tubes. Colburn j factors from the calculated results of circular and flat tubes in the heat exchangers are compared for various Reynolds number. The predicted results in this study can be applied to the optimal design of air conditioning system. with compact heat exchanger.

• 패션비즈니스
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• 제12권2호
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• pp.72-86
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• 2008

This research focused on determining the brassiere preference index and wearing status of chinese ladies in their 20's living in the Shanghai region of China, to help Korean lingerie companies in their development of bras to successfully advance into the Chinese lingerie market. The main research tool of this research was various different surveys, and the results of the surveys were evaluated using the SPSS 12.0 for Window program. The results of the survey can be summarized as: 1) consciousness and satisfaction level of the body. The satisfaction level of the brest was proportionate to the size of the brassiere, thus, people showed higher level of satisfaction for cone-shaped, semi-circular shaped, prominent-shaped(exposing), lifted-shaped brest over flat-shaped brest. Concerning the relationship between the shape of the brest and the age of the customers, people under 22 years of age preferred flat-shaped, and those between 23-24 years of age preferring exposing and lifted brest, thus as females mature and get older, the size of their brest increases, thus having preference on more circular and lifted-shaped brest and bras. 2) Status of bra wearing in China When we look at the size of the bra in relation to the shape of the brest, those classified as having 'flat-shaped' brest showed a high proportion of A-cups, ranging from 75A, 70A and 80A, where as those of 'cone-shaped' brest represented high ration of B-cups, ranging from 75B, 75A and 80B. Majority of those classified as having 'semi-circular shaped' and 'prominent-shaped(exposing)' brest showed a high ration in the size 80 range. And vast majority of those classified into the 'lifted-shaped' brest group, were reported of having C-cup size bras. 3) Status of Bra Purchasing As people mature, the main reason behind choosing a bra was the actual design of the bra, where they emphasized the importance of aesthetic values. People classified as having 'flat-shaped' and 'cone-shaped' brest emphasized the importance of design and beauty, while those having 'semi-circular shaped,' 'prominent-shaped(exposing),' and 'liftedshaped' brest groups emphasized the importance of hygiene and the material(fabric) of the bra. This shows that when people have relatively smaller brest, they emphasize the importance of external appearance whereas when the size of the brest increases, they pay more attention to the function of the bra rather than the external appearance.

• 한국식품영양학회지
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• 제29권5호
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• pp.670-676
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• 2016

서기 530년부터 1950년까지의 고조리서 32권에 수록된 장 만드는 방법 중 메주 만드는 방법을 언급한 225가지 중 재료의 가열방법, 메주의 형태, 메주를 띄우는데 사용하는 용기, 덮개 및 깔개를 분석하였다. 그 결과 전통 메주의 콩이나 전분질의 가열 방법은 찌기 57가지, 삶기 58가지, 볶아 삶기 21가지, 밥짓기 2가지의 순으로 나타났다. 메주의 형태는 알 41가지, 구형 27가지, 덩어리 22가지, 칼자루형 8가지, 납작형 6가지, 쪼가리형 4가지, 구멍형 1가지, 사각형 1가지의 순으로 나타났다. 고추장 메주 72가지 중 콩 가열 방법은 삶기 9가지, 찌기 6가지의 순이었고, 전분질의 가열방법은 떡찌기 19가지, 밥 짓기 11가지, 익반죽 삶기 5가지의 순으로 나타났다. 콩메주 띄우는 용기는, 가마니 섬 섶 49가지, 독 5가지, 둥구미 멱서리 14가지, 온돌 11가지, 소쿠리 채반 광주리 7가지, 독 5가지, 흙도랑 4가지, 시루 오쟁이 3가지, 바가지 2가지, 시루 2가지, 용수 1가지의 순으로 나타났다. 메주 띄우기용 덮개나 깔개는 짚 36가지, 닥나무잎 17가지, 멍석 거적 자리 15가지, 쑥 14가지, 솔잎 11가지, 콩잎 10가지, 도꼬마리잎 6가지, 북나무잎 6가지, 보릿짚 6가지, 뽕잎 6가지, 가랑잎 5가지, 띠풀 5가지, 삿자리 4가지, 헝겊 3가지, 개오동나무잎 2가지, 갈잎 1가지의 순으로 나타났다. 매달기는 5가지 밖에 없었다.