• 설비공학논문집
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• 제30권4호
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• pp.159-166
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• 2018

The Korean fenestration energy consumption efficiency rating system only considers thermal performance of the heat transfer coefficient (U-value) and airtightness excluding optical characteristics of the solar heat gain coefficient (SHGC). This study analyzed annual heating and cooling energy requirements on the middle floor of apartment by optical and thermal performance of windows to evaluate the suitability of the rating system. One hundred and twenty-eight windows were analyzed using THERM and WINDOW 7.4, and energy simulation for a reference model of an apartment house facing south was performed using TRNSYS 17. The results showed that window performance was the main factor in the heating and cooling load. The heating load of the reference model was 539 kWh to 2,022 kW, and the cooling load was 376 kWh to 1,443 kWh. The coefficient of determination ($R^2$) of the heating and cooling loads driven from the SHGC were 0.7437 and 0.9869, which are more compatible than those from the U-value, 0.0558 and 0.4781. Therefore, it is not reasonable to evaluate the energy performance of windows using only the U-value, and the Korean fenestration energy consumption efficiency rating system requires a new evaluation standard, including SHGC.

• Nuclear Engineering and Technology
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• 제52권6호
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• pp.1297-1303
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• 2020

In this study, nuclear radiation shielding and rigidity parameters of Y (0.1-x)B0.6Bi1.8O3La2x glassy system were investigated in order to determine it's suitability for use as nuclear radiation shielding materials. Therefore, a group of bismuth borate glass samples with La₂O₃ additive were synthesized using the technique of melt quenching. According to the results, the increase of the La₂O₃ additive increases the density of the glass samples and the mass attenuation coefficient (μ_m) values, whereas the half-value layer (HVL) and mean free path (MFP) values decrease. The effective atomic number (Z_eff) is also enhanced with an increment of both mass removal cross section for neutron (Σ_R) and absorption neutron scattering cross section (σ_abs). In addition to the other parameters, rigidity parameter values were theoretically examined. The increase of La₂O₃ causes some other important magnitudes to increase. These are the average crosslink density, the number of bonds per unit volume, as well as the stretching force constant values of these glass samples. These results are in concordance with the increase of elastic moduli in terms of the Makishima-Mackenzie model. This model showed an increase in the rigidity of the glass samples as a function of La₂O₃.

• 한국경제지리학회지
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• 제16권3호
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• pp.458-471
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• 2013

본 논문은 토지 이용 변화를 예측하는 계량 모형의 정확도 평가에 필수적인 통계량인 성능 지수를 심도 있게 이해하는 것을 목적으로 한다. 이 통계량은 기존의 토지 이용 변화 연구에서 소개된 예측 모형의 정확도를 평가하는 다른 통계량들 (예: 카파 통계량)의 단점을 보완하여 만들어진 것이나, 이 또한 계량 모형의 예측력을 명확하게 평가하고 해석하기에는 제한적이다. 본 논문에서는 성능 지수의 보다 명확한 해석을 위해서 결과물의 공간해상도를 고정해야 함을 밝히고, 그 특정 공간해상도를 "성능 해상도"라 정의한다. 성능 해상도는 예측오류가 현격하게 줄어들면서 계량모형의 예측력이 증가하는 시점의 공간해상도를 일컫는다. 따라서 토지 이용 변화 예측 모형의 예측력을 정확하게 평가하기 위해 두 통계량, 즉 성능 지수와 성능 해상도를 함께 이용할 것을 제안한다.

• Human Ecology Research
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• 제52권2호
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• pp.141-150
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• 2014

The purpose of the present study was to determine the structural relationship among the father's participation in childcare, parenting stress, marital satisfaction, and the job satisfaction of working mothers. This study is based on the 2011 Panel Study on Korean Children, a large, population-based study conducted by the Korea Institute of Child Care and Education. The participants were 431 working mothers. To ensure the reliability and validity of the questions, descriptive statistics of the frequency, ratio, average, standard deviation, skewness, and kurtosis were obtained using SPSS 21.0. Exploratory factor, variables correlation, and reliability analysis were also performed. The structural analysis using AMOS 20.0 in the bootstrapping method was conducted to perform a path analysis among the variables and to assess the suitability of the model. A hypothetical model was proposed, which was composed of a father's participation in childcare as an exogenous variable and parenting stress, marital satisfaction, and job satisfaction of a working mother as the endogenous variables. The results of this study are as follows: First, a father's participation in childcare and the parenting stress and marital satisfaction of a working mother affect the job satisfaction of the mother. The most influential factor is marital satisfaction. Second, marital satisfaction has mediating effects between the father's participation in childcare and the parenting stress and job satisfaction of the working mother. Third, parenting stress does not affect job satisfaction.

• 한국한의학연구원논문집
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• 제14권2호
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• pp.113-119
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• 2008

In pulse diagnosis, floating pulse and sinking pulse are frequently used for diagnosis about where disease is located and how much severe they are. However, in what mechanism floating pulse and sinking pulse arise is not known well. There are two point of views on substantial of floating pulse and sinking pulse. The first one is the floating and sinking degrees is the expression on the depth of pulsation. And, the second one is floating and sinking pulse is based on the response of pulsation to the indent pressure on radial artery. In this paper, we discussed these two opinions in the view point of tonometric measurement. The process for diagnosis on floating pulse and sinking pulse is similar to the tonometric measurement for non invasive blood pressure or intraocular pressure. We modelled the degrees of depth of pulsation with different indent pressures for initial pulsation feeling and different slopes of indent pressure lines. From this modelling, we can confirm the effect of pulsation depth on P-H curve, that is, in the model where lower pulsation is assumed, the shift of optimal indent pressure to the right was observed. The response of pulse pressure to the indent pressure was tried to be modelled with the degrees of mean blood pressure. Consequently, we tried to model the phenomenon of floating and sinking pulse for the first. And, from this modelling, we can get abundant understanding on how floating and sinking pulse can be caused. In the further study, we want to prove the suitability of this tonometric measurement based modelling with various studies including ultrasound measurement for the depth of pulsation in different EMI subjects.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.278-283
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• 2006

2005년 공공시설의 조기 공급을 통해 국민의 시설편익을 향상시키고자 도입된 BTL(Build - Transfer - Lease: 임대형 민자사업)을 통해 2006년 15개 시설유형, 84개 사업에 총 8조 3147억원이 투입될 계획이다. 그러나 일부 대형업체는 수익률이 저조하다는 이유로 BTL사업에 대한 투자를 꺼리고 있고, 특히 부분적으로 수익이 발생하는 사업에 대해서도 일괄적으로 BTL방식을 적용할 경우 수익률이 더욱 저하될 수 있는 문제가 있다. 따라서 본 연구에서는 수익성이 낮은 부분은 BTL방식으로 운영함으로써 사용자의 편익을 도모하고, 한편 수익성이 높은 부분은 민간투자자에게 운영권을 부여는 BTO방식으로 운영함으로써 사업의 수익률을 향상시킬 수 있는 BTL+BTO방식을 제안하고 운영기간을 기반으로 하는 BTL+BTO방식의 수익성 산정모델을 제시하였다. 그리고 본 모델을 실제 00지역 관사사업을 적용함으로써 BTL+BTO방식의 운영기간을 산정하여 BTL방식의 운영기간을 비교함으로써 BTL+BTO방식의 모델의 적절성을 검증하였다.

• 한국산학기술학회논문지
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• 제16권10호
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• pp.6458-6465
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• 2015

모바일 어플리케이션의 잦은 변경으로 인해 모바일 서비스의 관리가 부담이 되고 있으며, 이에 중앙관리가 용이한 모바일 웹 서비스 개발이 증가하고 있다. 모바일 웹 서비스 개발에 대해 개발자뿐 만 아니라 일반 사용자도 쉽게 개발할 수 있는 도구들이 개발되고 있다. 그러나 모바일 웹 서비스를 일반 사용자가 동적으로 구현하기 위한 표준화된 메타모델의 연구가 미흡한 상황이다. 이에 본 논문에서는 동적으로 모바일 웹 서비스를 개발할 수 있는 메타모델을 제안한다. 동적 메타모델은 XPDL 구조를 이용하여 모바일 웹 페이지와 모바일 웹 페이지 인스턴스, 그리고 동적 연결로 구성된다. 연결 메타모델에 대해 조건연결, 분기연결, 결합연결에 대해 연구하며, 최종적으로 전체 모델들을 통합하여 통합메타모델을 제안한다. 또한, 동적 메타모델의 적합성을 검증하기 위해 각 메타모델에 대해 XPDL 기반으로 사례 연구를 수행한다.

• 한국산학기술학회논문지
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• 제13권1호
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• pp.73-86
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• 2012

본 연구는 대학에서 경영 시뮬레이션 게임을 활용하는 교과과정의 도입과 운영을 위한 적합성을 높이기 위한 목적으로 수행되었다. 이를 위해 국내 기업, 기업체 교육기관, 국내외 대학의 활용실태와 수요자인 대학생의 수요를 조사하고 분석하였다. 분석에 기초하여 경영시뮬레이션게임을 적용한 교과모형을 경영대생 대상과 공대생 대상으로 설계하였다. 연구 방법으로는 문헌연구를 통해 연구동향을 확인하고, 국내 기업과 기업체 교육기관의 현장 전문가에 대한 면담조사를 실시하였으며, 국내외 대학의 활용실태를 강의계획서 조사를 통해 분석하였다. 결과로는 소수의 대학과 기업체들이 경영시뮬레이션게임을 부분적으로 실습하는 일부 교과목을 단기간으로 실시하고 있었다. 관련 연구단체가 전무하고 국내 기업의 경영상황과 운영 현실을 반영한 교육콘텐츠들이 상대적으로 부족한 실정이었으나 대학생 수요자의 기대가 크고 현장에서 새로운 경영교육 도구로써 활용성과를 확인하였다는 의의를 갖는다. 연구결과는 대학의 경영학 실습수업과 기업체 직원교육의 교육과정 운영에 사용이 기대된다.

• 소성∙가공
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• 제29권4호
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• pp.203-210
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• 2020

In this study, formability and springback behavior of 1.5 GPa grade ultra-high strength steel (UHSS) sheet were predicted through the finite element simulation, and structural stability of the forming dies was verified by the coupled forming-structural analysis. Uniaxial tension and uniaxial tension-compression tests were performed to obtain experimental data for modeling the springback properties of the sheet material. The springback values predicted by simulation were compared with those from actual measurements. The results calculated from the kinematic hardening model were found to be much more accurate than those from the isotropic hardening model. Deformation of the forming die and springback of the product were calculated by the coupled forming-structural analysis. The higher the strength of the die material, the smaller the surface displacement of the die and the springback of the product. The internal stresses of the dies made of three materials, FC300, FCD550 and STD11 were compared with the yield stress of each material. The results provided a basis for determining the most suitable material for each part of the die set. As a result, simulation techniques have been established for predicting formability and springback in the UHSS sheet forming process.

• 한국농림기상학회지
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• 제6권1호
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• pp.61-69
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• 2004

A long-term growth simulation was performed at 99 land units in Yeoncheon county to test the potential adaptability of each land unit for growing soybean cultivars. The land units for soybean cultivation(CZU), each represented by a geographically referenced land patch, were selected based on land use, soil characteristics, and minimum arable land area. Monthly climatic normals for daily maximum and minimum temperature, precipitation, number of rain days and solar radiation were extracted for each CZU from digital climate models(DCM). The DCM grid cells falling within a same CZU were aggregated to make spatially explicit climatic normals relevant to the CZU. A daily weather dataset for 30 years was randomly generated from the monthly climatic normals of each CZU. Growth and development parameters of CROPGRO-soybean model suitable for 2 domestic soybean cultivars were derived from long-term field observations. Three foreign cultivars with well established parameters were also added to this study, representing maturity groups 3, 4, and 5. Each treatment was simulated with the randomly generated 30 years' daily weather data(from planting to physiological maturity) for 99 land units in Yeoncheon to simulate the growth and yield responses to the inter-annual climate variation. The same model was run with input data from the Crop Experiment Station in Suwon to obtain a 30 year normal performance of each cultivar, which was used as a "reference" for evaluation. Results were analyzed with respect to spatial and temporal variation in yield and maturity, and used to evaluate the suitability of each land unit for growing a specific cultivar. A computer program(MAPSOY) was written to help utilize the results in a decision-making procedure for agrotechnology transfer. transfer.