• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.869-874
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• 2003

The atomization characteristics were investigated through the influence of the change of GLR and the change of working fluid on droplet size distribution and mean diameter of drop produced by effervescent atomizer. For simultaneous injection of water and high viscous waste vegetable oil, effervescent atomizer with two aerator tubes was specially designed. From the experimental results, regardless of mass fraction of vegetable oil in working fluids, it is expected that effervescent atomizer will exhibit excellent atomization performance at the high GLR conditions.

• 대한기계학회논문집
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• 제16권5호
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• pp.933-942
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• 1992

본 연구에서는 이상류 동축 노즐의 미립화 기구를 규명하기 위한 기초단계로 20˚의 증류수를 사용하여 이상류 동축노즐의 평균액적 직경에 미치는 공급유량의 영 향을 직접사진 촬영법을 사용하여 규명하고자 한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.434-440
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• 2000

The atomization characteristics of air-assist atomizer which is surrounded by a coflowing airstream is investigated. The air-assist, coflow air stream had swirl imparted to them in the same direction with 45 degree's angle swillers. The fuel and air entered the combustor at ambient temperature and the combustor was operated in an unconfined environment. Diesel fuel was used for all the experiments. Drop size and mean velocity are reported for certain distances downstream from the nozzle. The droplet size and velocity measurements were performed using a two-component phase/Doppler particle analyzer and velocity profiles across the entire flowfield are presented.

• 한국분무공학회지
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• 제11권3호
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• pp.131-139
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• 2006

An experimental study was performed to investigate the liquid breakup and atomization characteristics in electrohydrodynamic atomization according to the changing of experimental parameters such as nozzle size, fluid flow, and electrical intensity. An original electrohydrodynamic atomizer equipment was designed and manufactured for the analysis of spray visualization and the exploration of relationship between applied power and the behavior of liquid atomization. The image processing technique by using the back-illumination method was applied to visualize the distilled liquid breakup process and to examine the variation of the droplet size distribution. The results show that the spray modes of electrohydrodynamic atomization are closelyconnected by the strength of the electric stresses at the surface of the liquid film and the kinetic energy of the liquid jet leaving the needle tip.

• 청정기술
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• 제14권4호
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• pp.242-247
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• 2008

화장품, 의약품, 전자소재 분야에서 생체적합, 생분해성 고분자로 널리 사용되는 폴리비닐피롤리돈(PVP)을 에어로젤 용매추출 방법에 의해 미세입자를 제조하였다. 용매로는 이 염화메탄올, 반용매로는 초임계 이산화탄소가 사용되었다. 온도, 압력, 이산화탄소 유량, 용액유량의 작업조건에 따라 0.184 - $0.249\;{\mu}m$입자크기를 얻었고, 그 입자크기에 영향을 미치는 초기구형 입자크기와의 상관관계를 규명하였다.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1995년도 추계학술대회논문집
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• pp.249-267
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• 1995

The purpose of this study is to analyze breast shape by age, to classify breast types and then to suggest brassiere size chart. The subject of anthropometric measurement were 232 women in 20's and 40's. The direct anthropmetric measurement were analyzed by mean, standard deviation, duncan test, T-test, ANOVA, factor & cluster analysis The results are as follows; 1) as a result of analysis for the measurements, according to the increase of age, the items of height were decreased and the items of width, depth, cir- cumference, length were increased, being obesity and breast points were dropped. So the volume and bottom area of 40's women's breast were lager than 20's women's. The width of breast points was bide by increasing of intereior. 2) as a result of factor analyxis, 5 factors were extracted as important factor of breast shapes(obesity of breast and location of breast point, breast height and volume, upper dimensions of breast/lower dimensions of breast, interior dimensions of breast/exterior dimensions of breast, volume of the lower part and drop of breast) 3) as a reslut of cluster analysis, the breast shape were classified into 4 types. namely, typel has the smallest volume, bottom area of breast and the slenderest breast, type2 was the second obesity type. type3 was middle sized type. type4 has much dropped, wide bottom area of breast and the biggest form. 4) To establish brassiere sizing system, the loss funtion was used to decide interval of under bust girth and cup size of size chart. 20 brassiere sizes were established and the size chart covers 92.2% of all subject.

• 패션비즈니스
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• 제11권2호
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• pp.155-171
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• 2007

This research aims to present the corresponding dimensions of China men's clothes on the basis of size specification of Korea men's suits. The results of this study, with the cooperation of Sejung Company exporting men's clothes to Ningbo City, Zhejiang Province in China, are as follows: 1. Based on the drop standard of KS K 0050, the body types of Chinese men in their 20s were classified. A body types were 55.77%, Y body types were 32.16%, B body types were 11.55% and BB body types were 1.51%. 2. According to the criteria of ready-made dimensions of normal body type suggested in Korea Standards, and in consideration of the basic distribution reality of body dimensions, representative 5 sizes were selected. 3. Research jackets by different sizes were produced and went through wearing tests. The means of 1st wearing test were 3.86, 4.09, 4.09, 3.57, and 3.69. The mean of 2nd wearing test of 88-73-170 size was 4.32. 4. The corresponding size specification of China men's clothes based on those of Korea men's suits were presented here, showing product sizes and physical items in detail.

• 한국분무공학회지
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• 제10권1호
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• pp.43-52
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• 2005

The effect of fuel injection spray on engine performance has been known as one of the major concerns for improving fuel economy and reducing emissions. In general, reducing the spray droplet size could prevent HC emission in gasoline engine. As far as PFI (Port Fuel Injection) gasoline engine is concerned, the mixture of air and fuel may not be uniform under a certain condition, because breakup and production of spray droplets are made in a short distance between the fuel injector and intake valve. This study, by constituting PFI gasoline spray system, was performed to study the transient spray characteristics and dynamic behavior of droplets from 2hole 2spray type injector used in DOHC gasoline engine. Mean droplet size and optical concentration in accordance with various conditions were measured by LDPA and CCD camera. Through this study, the variation of drop size and optical concentration could be used for understanding the behavior of unsteady spray was declared and the existing the small droplets between each pulse spray could be estimated caused to the development of wall film was conformed.

• 한국자동차공학회논문집
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• 제13권5호
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• pp.64-74
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• 2005

The effect of fuel injection spray on engine performance has been known as one of the major concerns for improving fuel economy and reducing emissions. In general, reducing the spray droplet size could prevent HC emission in gasoline engine. As far as PFI gasoline engine is concerned, the mixture of air and fuel may not be uniform under a certain condition, because breakup and production of spray droplets are made in a short distance between the fuel injector and intake valve. This study, by constituting PFI gasoline spray system, was performed to study the transient spray characteristics and dynamic behavior of droplets from two-holes two-sprays type injector used in DOHC gasoline engine. Mean droplet size and optical concentration in accordance with various conditions were measured by LDPA and CCD camera. Through this study, the variation of drop size and optical concentration could be used for understanding the behavior of unsteady spray was declared and the existing the small droplets between each pulse spray could be estimated caused to the development of wall film was conformed.

• 한국의류학회지
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• 제26권5호
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• pp.691-702
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• 2002

The purpose of this study was to provide basic information on the propriety of the ready to wear garment sizes of Tween Generation(ages from 5th grade to 8th grade) who has different clothing preferences in color, styles, and design and also different body sizes and shapes from younger and older students. The objectives of the study were to ascertain (a) the body figure changes occurring during Tween Generation; (b) the coverage of manufactures'garment sizes. The body measurements of elementary school students(5th & 6th grades) and junior high school students(7th & 8th grades) provide the basic statistics for this study. The mean differences of each size within each figure type are compared by using t-teats. The differences in various manufacturers'apparel sizing and figure size are investigated. Also the body measurements and the apparel sizes of the manufacturers are compared in order to evaluate the suitability of the garment size. Results indicate that the body type factors are different in each age group. And manufactures'sizes come out to be much smaller than the actual body measurements. Young casual wear can cover junior high school students satisfactorily but for elementary school students, because of low drop-value, the overall satisfaction with filling is low.