• 한국실내디자인학회논문집
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• 제13권2호
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• pp.142-149
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• 2004

The purpose of this research is to find out the relationship between housing environment and elementary school children's personality. The samples of this research are 459 children from elementary schools in their fourth or higher year grades. The results were analyzed using frequency, percentage, and t-test, F-test and multi regression. The findings indicated that housing type does not have effect on environmental characteristics of children's room, while housing ownership type, housing size and children's room size have significant effects on them. Housing size and children's room size have significant effects on children's satisfaction. The larger children room provides higher satisfaction with children room environment. The finding showed that environmental characteristics of children's room have relationship with children's personality. The order of environmental characteristics of children's room has the highest relationship with children's personality.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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• pp.71-74
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• 2002

In this study, resonant characteristics of $Pb_{0.88}(La_{0.6}Nd_{0.4})_{0.08}(Mn_{1/3}Sb_{2/3})_{0.02}Ti_{0.98}O_3$ ceramics were investigated with the variations of electrode radius size for manufacturing the best 30MHz SMD type ceramic resonator with the size of $3.7{\times}3.1{\times}0.255mm^3$. Physical properties were proper for appling for 30MHz SMD type ceramic resonator. In third overtone thickness vibration mode, with increasing electrode radius size, resonant resistant($Z_r$) was decreased gradually. Mechanical quality factor($Q_{mt3}$) and dynamic range(D.R) showed the maximum value of 2,283, 47.1dB respectively, at 0.74mm electrode radius size.

• Journal of the Optical Society of Korea
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• 제4권1호
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• pp.58-61
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• 2000

Viewing zone shape and size perform a key role in creating viewing comfort for the viewer. The horizontal and vertical sizes of viewing zones, formed by a full color transmission type holographic screen with a stereoscopic image projection are investigated. The screens have been recorded as holograms of a narrow stripe shaped object with different width; to extend the vertical size of the viewing zone the holograms were exposed two times with the hologram shifting between exposures. The viewing zone parameters were measured as a function of the stripe width of the object and of the exit pupil size of projection optics for several holographic screens having the size of the 30 $\times$ 40 $\textrm{cm}^2$.

• 산업경영시스템학회지
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• 제43권3호
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• pp.87-94
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• 2020

In this study, the factors affecting the efficiency of 48 projects of private R&D institutes were analyzed using the Tobit model. Influencing factors were selected as open R&D network size, IT industry, interaction between R&D network size and IT industry, and type of R&D network cooperation. As a result of Tobit analysis, the R&D network size, the IT industry, and the type of R&D network cooperation were found to be significant. The larger the open R&D network size, the lower the efficiency, and the IT industry showed lower R&D efficiency than other industries. In addition, cooperation with universities and research institutes showed lower R&D efficiency than cooperation with companies. As a result of these studies, companies will be able to select and focus on cooperation with the outside in relations and investment allocation.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.972-973
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• 2007

Relationships between field effect mobility and grain size on pentacene thin-film transistors with $polyimide/SiO_2$ gate dielectrics have been studied. 6 kinds of polyimide were used as surface treatment gate dielectric layer. Grain size of the pentacene thin film were between 5 and $30\;{\mu}m$ and depended on the polyimide. The field effect mobility were also depended on the polyimide and the those values were from 0.027 to $0.69\;cm^2/(Vs)$. The field effect mobility tends to increase with increasing the grain size. Precursor type polyimide containing polyamic acid show better mobility of $0.69\;cm^2/(Vs)$ than soluble type polyimide. Bias stress characteristics in air are discussed in the basis of the grain size.

• 설비공학논문집
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• 제18권7호
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• pp.556-562
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• 2006

The objectives of this paper are to analyze simultaneous heat and mass transfer performance for a plate type bubble absorber with binary nanofluids numerically and to investigate the effects of binary nanofluids and surfactants on the size of the bubble absorber. The effective absorption ratio represents the effect of binary nanofluids and surfactants on the absorption performance. The kinds and concentrations of nano-particles and surfactants are considered as the key parameters. The results show that the addition of surfactants can reduce the size of absorber up to 74.4%, the application of binary nanofluids does the size up to 63.6%. Combination of binary nanofluids and surfactants can reduce the size of absorber up to 77.4%.

• 한국지열·수열에너지학회논문집
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• 제11권2호
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• pp.7-11
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• 2015

Recently, as the demand for sustainable energy sources is increasing, ground-source heat pump (GSHP) systems are receiving growing attention. However, the initial cost of GSHP system is higher than it of the conventional systems, especially, in small-size buildings. Therefore, for the application to the small-size building, it is necessary to develop small-size ground heat exchanger with small-size buildings. In this study, analysis of unit-type heat exchanger due to grouting materials. As a result, 1492.14 W of heat exchange rate was acquired in the condition of cement-silica sand-graphite materials.

• Korean Chemical Engineering Research
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• 제62권3호
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• pp.214-224
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• 2024

밸브는 유량과 압력 조절 등의 중요한 역할을 수행하며, 적절한 밸브 사이즈와 유형 선택이 필요하다. Engineering Procurement Construction (EPC) 산업에선 밸브 사이즈 계수(C_v)의 수식적 계산을 바탕으로 사이즈와 유형을 선정해왔으나 이러한 방식은 전문가의 많은 시간과 비용이 요구되어 비효율적이다. 본 연구는 이를 해결하기위해 머신 러닝기법을 이용한 밸브 사이즈 및 유형 예측 모델을 개발하였다. Artificial neural network (ANN), Random Forest, XGBoost, Catboost의알고리즘을 적용하여 모델들을 개발하였으며, 평가 지표로는 사이즈 예측에는 Normalized root mean squared error (NRMSE)와 R²를, 종류 예측에는 F1 score를 적용하였다. 또한, 유체 상에 따른 영향을 확인하고자 유체 전체, 액체, 기체, 스팀의 4개의 데이터 세트로 사례 연구를 진행하였다. 연구 결과, 사이즈의 경우 전체, 액체, 기체에선 Catboost(R²기준, 전체: 0.99216, 액체: 0.98602, 기체: 0.99300. NRMSE 기준, 전체: 0.04072, 액체: 0.04886, 기체: 0.03619)가, 스팀에선 Random Forest가(R²: 0.99028, NRMSE: 0.03493) 가장 뛰어난 모델임을 확인하였다. 종류의 경우 Catboost가 모든 데이터에서 가장 높은 성과를 제시하였다(F1 score 기준, 전체: 0.95766, 액체: 0.96264, 기체: 0.95770, 스팀: 1.0000). 본 연구에서 제안한 모델들을 적용할 경우, 주어진 조건에 따른 밸브 선택을 도와 의사결정 속도를 높여줄 것으로 기대된다.

• 복식문화연구
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• 제18권5호
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• pp.892-907
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• 2010

The purpose of this study was to compare torso pattern made by draping and flat pattern method in terms of the size of breast. The size of this study was classified as 75A and 75D according to the size of breast. Each torso pattern by the combination of the size and pattern method was compared and analyzed. In order to test the fit of the draping and flat pattern that was developed according to the size of breast, the outer appearance was evaluated. The results of the study were as follows: First, The most striking size difference was difference between the front and the back on bust line level, which decides on position of the side seam in comparison of size between draping and flat pattern of 75A and 75D. In the flat pattern, the difference between the front and the back in the size of breast was consistent regardless of a change in the size of breast. However, in the draping, the bigger breast led to the bigger difference between the front and the back on bustline level. Second, the flat pattern in 75D was evaluated to be the worst in 27 items among total 46 items for the evaluation of outer appearance in the draping and flat pattern of 75A and 75D. Third, regardless of size, the draping was evaluated to be more suitable in the areas related to neck, arm hole, and waist dart than the flat pattern. These results are suggesting that the draping is a method of reflecting characteristic of the body type more accurately than the flat pattern, and that the draping is a more suitable method than the flat pattern for the design of clothing pattern of the body type with big breast like 75D.

• 가정과삶의질연구
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• 제11권2호
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• pp.13-29
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• 1993

The Purpopse of this study are to classify the lifestyles of urban housewives with automobiles living in Gwangju to see their relationship between lifestyle and demographic social and econo-mic variables and to see the relationship between lifestyle and prepurchase information search activity. For these purpose a survey was conducted using questionaires on 410 The data was collected from March 8 to March 20 1993 and analyzed by factor analysis cluster analysis Duncan test {{{{ chi ^2 }} }}- t e s t a nd ANOVA. The findings are classified into 7 types: enjoyable convenience type (15.6%) conservative sound and thrifty type(17.3%) rationative type (13.2%) thrifty life type (11.0%) passive-inactive type(8.3%) fashion-pursuity type(12.9%) 2) The lifestyles of he respondents showed significant difference according to their age education level employment status. length marriage consumer education and type of housing. 3) The lifestyles of the respondents showed a difference only automobile attitude While showing no significant difference by automobile size information sources of automobile priority of automobile attitude and time spent in searching information The lifestyle of respondents showed a difference by automobile price size quality secuity warranty service and maintenance cost. 4) Among the lifestyle patterns of the respondents the passive-inactive type and rationative typ were positive about all the prepurchase information activity of automobile.