• 한국태양에너지학회 논문집
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• 제25권4호
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• pp.53-60
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• 2005

The purpose of this study is to improve energy efficiency of windows in office buildings through the evaluation of their heating, cooling and illumination load. Energy efficiency is influenced by window size which is determined at the early stage of building design. The process of this study is as follows. First, energy performance is analysed according to the various rates of windows through computer simulation (ECOTECT). Then, the annual heating, cooling and illuminating loads according to the different window sizes are compared one another. Results indicated that the optimal window size considering energy efficiency is 50% of the surface area. When the window size is 50% of the surface area, annual maintenance expense is also smallest. Since the cost of cooling is larger than that of heating, too low indoor air temperature in summer is unfavorable based on the reasonable annual maintenance expenses.

• 한국화재소방학회논문지
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• 제12권3호
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• pp.21-30
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• 1998

본 연구는 실제 화재실험을 통하여 구획 화재 시 일어날 수 있는 창유리의 파괴 형태 및 시간 그리고 개구 조건과의 관계 등을 고찰하고자 했다. 화재 시 창유리의 파괴현상은 창호 유리 중간 부분과 프레입 안에 있는 유리부분의 현저한 온도차이로 인한 열웅력으로 일어남을 확인했다. 실험 1-3은 프레엄 내부와 유리면의 온도차가 233.4$^{\circ}C$ 였으며, 실험 2-1은 138$^{\circ}C$, 실험 2-2는 83.6$^{\circ}C$의 차이를 보였다. 파괴 발생 시 실내의 온도는 실험 2-1의 경우 434.4$^{\circ}C$, 실험 2-2는 83.6$^{\circ}C$의 차이 를 보였다. 파괴 발생 시 실내의 온도는 실험 2-1의 경우 434.4$^{\circ}C$, 실험 2-2는 440.6$^{\circ}C$ 실험 2-3 은 400.9$^{\circ}C$를 기록하여 화염이 직접 닿지 않는 경우의 균열은 400-50$0^{\circ}C$의 온도에서 발생한다. 화재로 인한 창유리(한글라스 플로탱 유리)는 1541.14kW의 화재에 노출되었을 시 열웅력에 의한 파괴가 일어나기는 하나 유리면이 파괴에 의해 개구부가 되지 않는다.

• KIEAE Journal
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• 제13권4호
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• pp.27-32
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• 2013

This study focus on shaft box facade, special form of box window construction. It consists of a system of box window with continuous vertical shafts that extend over a number of stories to create a stack effect. The subject building was decided by analyzing various types of exiting apartments. Shaft box type balcony was devised by setting up shaft space at a part of balcony. Air flow and indoor air temperature were simulated, performance of shaft box type balcony was compared with existing types using VE computer simulation program. Research consequence can be summarized as follow: 1) In the case of existing types, the change of window opening rate has only a little effect on the improvement of indoor temperature. But, air flow rate increased two times in the case that changed opening rate 20% to 40% 2) In the case of existing types, the growth of air flow rate has little effect on the improvement of indoor temperature. But, shaft box type represented the remarkable effect on the improvement of indoor temperature as well as the growth of air flow rate.

• 교육시설 논문지
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• 제25권4호
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• pp.19-30
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• 2018

The school classroom is a common living place where students spend 7 to 14 hours a day to prepare for their careers. Therefore, if the ventilation of the classroom is not properly performed, it may lead to the deterioration of learning ability due to the unclear air. The concentration of carbon dioxide in the classroom is reported to be high, and the increase in carbon dioxide concentration has a negative effect on the learner's academic performance. In this context, the purpose of this study is to propose a methodology for intelligent and responsive window opening-closing operation process that can reduce the concentration of $CO_2$ in the classroom in order to build a support space that can create an effective teaching-learning environment for adolescents. The specific objectives are as follows. First of all, we define the concept of window opening-closing operation. Secondly, twe develop the operation process of window opening-closing. Thirdly, we develop an algorithm for real-time window opening and closing (process) (Window Opening-Closing Operation Process). Finally, we verify the intelligent responsive window opening-closing operation process through developing examples of window opening-closing operation process using the parametric design program. This study is a preliminary study to develop algorithms necessary for window opening-closing operation. Based on the first-order algorithm, We simulated window opening-closing operations according to a hypothetical scenario. As a result, This study can show that the window is open and close depending on the $CO_2$ concentration, but the $CO_2$ concentration in the room is higher than outdoors. Consequentially, we suggest that it is necessary to develop an algorithm to supplement these results because window is often not working when the temperature difference between indoor and outdoor in winter is large.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.51-53
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• 2001

Permanent Magnet DC Motors are widely used in Automotive parts because they have cheap price, simple structure and high torque-speed ratio. But the motor in automotive parts is required high quality, complex function and lower price than before. This paper deals with design of controller for safety function that body trap on the automotive window. The algorithm of controller can adapt variety conditions with temperature, electrical, driving, etc.

• 설비공학논문집
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• 제14권7호
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• pp.543-551
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• 2002

Gravity ventilators allow the escape of the warm air and air contaminants due to both (either) buoyancy and (or) convection. As a natural ventilation strategy, various gravity ventilators can be installed on the roof. Ventilation efficiency could be affected by various parameters, such as, area of openings, wind velocity and incidence angle, temperature difference between inside and outside, and shape of ventilator. Especially, the shape of roof gravity ventilator might be one of influencing factors for the effective ventilation. The window type gravity ventilators are frequently installed instead of general (standard) gravity ventilator. However, the ventilation efficiencies of them were not proved yet. To compare the ventilation efficiency, general type ventilator and two window type ventilators were numerically tested. Mean age of air, temperature and CO concentration were predicted by using commercial CFD code, AIRPAK (Ver. 2.0) with various conditions. The predicted result showed that general type ventilator is more effective for natural ventilation than window type ventilators.

• 대한원격탐사학회지
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• 제11권1호
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• pp.31-45
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• 1995

The values of brightness temperature difference (BTD) between 11um and 12um infrared channels may reflect amounts of low-level water vapor and cloud types due to the different absorptivity for water vapor between two channels. A simple method of classifying cloud types at night was proposed. Two-dimensional histograms of brightness temperature of the 11um channel and the BTD between the split window data over subareas around characteristic clouds such as Cb(cumulonimbus), Ci(cirrus), and Sc(stratocumulus) was constructed. Cb, Ci and Sc can be classified by seleting appropriate thresholds in the two-dimensional histograms. And we can see amounts of low-level water vapor in clear area as well as cloud types in cloudy area in the BTD image. The map of cloud types and low-level water vapor generated by this method was compared with 850hPa and 1000hPa relative humidity(%) of numerical analysis data and nephanalysis chart. The comparisons showed reasonable agreement.

• 한국태양에너지학회 논문집
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• 제38권3호
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• pp.29-36
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• 2018

The goal of this study is to retrofit the windows of residential buildings and to activate the green remodeling by verifying energy saving and indoor thermal environment. As a result of analysis of the energy saving effect of 458 units window retrofits, it was possible to reduce the energy requirement by 48.20% ~ 54.97%. According to the improvement on indoor environment, it was possible to operate by reducing heating temperature and supply time. The actual gas consumption of the heating period was reduced by 25% compared with that of the window retarder to save 28,968 thousand won of heating energy cost. Resident's satisfaction surveys were conducted one year after window retrofit. More than 80% of the respondents answered that they satisfied the improvement on window performance, indoor thermal environment and indoor sound environment. As a result, we verified the energy saving effect and the improvement on the indoor environment through window retrofits.

• 한국화재소방학회논문지
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• 제28권2호
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• pp.26-33
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• 2014

최근 국내에서는 건축물에서 공간의 미관이나 활용성 때문에 유리창 및 유리벽체의 사용에 대한 관심이 높아지고 있다. 하지만, 건축물의 내부공간은 화재시 연소확대 및 인명피해를 막기 위해 건축법에 따라 내화구조로 방화구획을 하여야 한다. 이러한 방화구획벽에 비차열 유리를 사용할 경우, 화재시 인접 거실로 복사열에 의한 화재의 확대, 인명 피해가 일어날 수 있다. 본 연구에서는 비차열 유리창에 대한 복사열의 위험성을 평가하기 위하여 내화실험을 실시하여 실험체 이면에서의 온도와 열류량을 측정하여 그 결과를 분석하였다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(3)
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• pp.193-198
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• 1996

The effect of dynamic strain aging (DSA) on the leak-before-break (LBB) analysis was estimated through the evaluation of leakage-size-crack and flaw stability in SA106 Gr.C piping steel. Also. the results were represented as a form of "LBB allowable load window". In the DSA temperature region. the leakage-size-crack length was smaller than that at other temperatures and it increased with increasing tensile strain rate. In the results of flaw stability analysis. the lowest instability load appeared at the temperature corresponding to minimum J- R curve which was caused by DSA. The instability load near the plant operating temperature depended on the loading rate of J-R data. and decreased with increasing tensile strain rate. These are due to the strain hardening characteristic and strain rate sensitivity of DSA. In the "LBB allowable load window". LBB allowable region was the narrowest at the temperature and loading conditions where DSA occurs.