• 제목/요약/키워드: shading ratio

검색결과 128건 처리시간 0.028초

사무소 건물의 외피요소가 냉난방 및 조명에너지 소비에 미치는 영향에 관한 연구 (A Study on the Effect of Envelope Factors on Cooling, Heating and Lighting Energy Consumption in Office Building)

  • 손장희;양인호
    • 조명전기설비학회논문지
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    • 제26권2호
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    • pp.8-17
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    • 2012
  • The objective of this study is to perform an analysis of the heat(heating and cooling) and lighting energy consumption according to the window area ratio and the application of horizontal louver, which is external shading device installed for the purpose of energy savings in office buildings. For this, a building was chosen as a typical example, and the heat and lighting energy consumption was calculated by using the daylight and building energy analysis simulation. The results showed that the total energy consumption, when the lighting control was applied, was reduced by an average of 11.49[%] compared to when there was no lighting control. The smaller the glazing ratio is, the less the total energy consumption is. Also, the application of the horizontal louver increases the total energy consumption under the same condition of glazing ratio.

An Effective Algorithm for Transmitted Solar Radiation Calculation through Window Glazing on a Clear Day

  • Oh, John Kie-Whan
    • KIEAE Journal
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    • 제14권4호
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    • pp.35-45
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    • 2014
  • The main objective of this study is to provide an effective algorithm of the transmitted solar radiation calculation through window glazing on a clear day. This algorithm would be used in developing a computer program for fenestration system analysis and shading device design. Various simulation methods have been evaluated to figure out the most accurate and effective procedure in estimation of transmitted solar radiation on a tilted surface on a clear day. Characteristics of simulated results of each step have been scrutinized by comparing them with measured results of the site as well as results from other simulation programs. Generally, the Duffie & Beckman's solar calculation method introducing the HDKR anisotropic model provided the most reliable simulation results. The DOE-2 program usually provided over-estimated simulation results. The estimation of extraterrestrial solar radiation and beam normal radiation were conducted pretty accurately. However, the solar radiation either on horizontal surface or on tilted surface involves complicated factors in estimation. Even though the estimation results were close to the real measured data during summer when solar intensity is getting higher, the estimation provided more error when solar intensities were getting weaker. The convex polygon clipping algorithm with homogeneous coordinates was fastest model in calculation of sunlight to shaded area ratio. It could not be applied because of its shape limitation.

Deep Learning-Based Low-Light Imaging Considering Image Signal Processing

  • Minsu, Kwon
    • 한국컴퓨터정보학회논문지
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    • 제28권2호
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    • pp.19-25
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    • 2023
  • 이 논문에서는 image signal processing 을 고려하여 저조도에서 촬영된 저품질의 raw 이미지를 딥러닝에 기반하여 개선하는 방법을 제안한다. 스마트폰 카메라의 경우 DSLR 카메라에 비해 렌즈나 센서의 확장에 제약이 있어 저조도 상황에서 이미지에 노이즈가 증가되고 품질이 저하되는 문제점을 보인다. 기존 딥러닝 기반 저조도 이미지 처리 방식은 image signal processing의 주요 요소인 렌즈 쉐이딩 효과와 화이트 밸런스를 고려하지 못하여 부자연스러운 이미지를 생성하기도 한다. 본 논문에서는 렌즈 쉐이딩 효과와 화이트 밸런스를 딥러닝 모델에 적용하기 위해 중심거리와 채널 평균을 활용한다. 스마트폰으로 촬영된 저조도 이미지를 통한 실험에서 제안하는 방법이 기존 방법에 비해 더 높은 peak signal to noise ratio 와 structural similarity index measure를 달성함과 동시에 높은 품질의 저조도 이미지를 생성함을 확인한다.

울릉연화바위솔 분화재배를 위한 적정 광도, 분용토 및 시비 수준 (Proper Light Intensity, Potting Media, and Fertilization Level for Potted Orostachys iwarenge for. magnus)

  • 정경진;천영신;최경옥;하수현;윤재길
    • 원예과학기술지
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    • 제30권4호
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    • pp.357-362
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    • 2012
  • 울릉연화바위솔을 분화로 재배하고자 할 때, 적정 광도와 내음성 정도, 적정 분용토, 그리고 적정 시비조건을 알아보기 위해 실험을 수행한 결과는 다음과 같다. 적정 광도를 알아보기 위해 광도를 52, 82, 90, 97% 차광을 하고 울릉바위솔을 재배한 결과, 52% 차광에서 생육이 가장 양호한 것으로 나타나 최적 광도는 차광율 52% 이하로 판단되었다. 또한 82% 차광구부터는 생육이 급격하게 저하되고 엽색도 엷어지는 것으로 나타나 울릉연화바위솔은 내음성이 비교적 약한 종류임을 알 수 있었다. 적정 분용토 선발을 위하여 마사토:유비상토(80:20, v/v), 마사토:유비상토(60:40), 유비상토:강모래(20:80), 마사토:유비상토:강모래(60:20:20)와 같이 4종류의 배합토를 이용하였다. 그 결과 마사토:유비상토:강모래(60:20:20)에서 지상부생체중, 초폭, 런너수 등에서가장 좋은 것으로 나타났다. 특히 지상부 생체중의 경우 다른 용토에서는 약 5-8g 범위였으나, 마사토:유비상토:강모래(60:20:20)에서는 16g으로 2배 정도의 생육량을 보였다. 시비조건은 하이포넥스 액비를 1,000배로 희석하여 1회/주처리했을 때, 생체중 및 초폭, 분지수 등에서 가장 좋게 나타났다. 특히 생체중의 경우 대조구(무처리)가 19g인데 비해 1,000배액 1회/주 처리에서 약 35g으로 84% 정도 생장량이 증가하였다. 대체적으로 액비농도가 높고 처리횟수가 많을수록 생육이 양호하였다.

차광처리에 따른 시설하우스 재배 고들빼기의 생육 및 생리활성 변화 (Shading Effect on Plant Growth and Physiological Activity of Youngia sonchifolia Grown in Plastic House)

  • 천상욱
    • 한국잡초학회지
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    • 제30권3호
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    • pp.215-224
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    • 2010
  • 고들빼기의 시설생산을 위해 배지조성 및 차광정도를 달리한 환경조건에 대한 생육특성과 그에 따른 생리활성 변이를 검토하고자 온실시험을 수행하였다. 고들빼기 시설재배를 위한 적정한 배지조합은 코코피트와 펄라이트를 각각 70:30과 50:50으로 혼합한 배지가 코코피트와 펄라이트의 단독배지보다 생육 및 수량에 있어서 유의적으로 높게 나타났다(P<0.05). 차광정도에 따른 고들빼기의 근장, 엽면적 및 생체중을 비롯한 생육은 무차광에서 가장 높게 나타났고 그 다음이 50%차광 및 70%차광 순이었다(P<0.05). 총페놀 함량(110.2~119.2mg $kg^{-1}$)과 총플라보노이드 함량(128.3~146.7mg $kg^{-1}$)과 같은 생리활성물질의 함량은 지하부보다는 지상부에서, 무차광보다는 차광에서 높게 검출되었다. 한편, DPPH 라디컬 소거능 측정을 통한 항산화성은 추출물 농도가 증가할수록 높은 활성을 보였고 지하부(47.7~49.8%)보다는 지상부(50.2~80.8%)에서, 차광보다는 무차광에서 높은 활성을 보였다.

시뮬레이션을 이용한 외부 베네시안 블라인드의 약식 SHGC 계산법 개발 (The Development of the Simple SHGC Calculation Method in Case of a Exterior Venetian Blind Using the Simulation)

  • 엄재용;이충국;장월상;최원기
    • 한국태양에너지학회 논문집
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    • 제35권2호
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    • pp.73-83
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    • 2015
  • When it comes to these buildings for business use, cooling load during summertime was reported to have great importance which, as a result, impressively increased interest in Solar Heat Gain Coefficient (SHGC). Such SHGC is considered to be lowered with the help of colors and functions of glass itself, internal shading devices, insulation films and others but basically, these external shading devices for initial blocking that would not allow solar heat to come in from outside the buildings are determined to be most effective. Of many different external shading devices, this thesis conducted an analysis on Exterior Venetian Blind. As for vertical shading devices, previous researches already calculated SHGC conveniently using concepts of sky-opening ratios. However in terms of the Venetian Blind, such correlation is not possibly applied. In light of that, in order to extract a valid correlation, this study first introduced a concept called shape factor, which would use the breadth and a space of a shade, before carrying out the analysis. As a consequence, the concept helped this study to find a very similar correlation. Results of the analysis are summarized as follows. (1) Regarding SHGC depending on the surface reflectance of a shade, an average of 2% error is observed and yet, the figure can always be ignored when it comes to a simple calculation. (2) As for SHGC of each bearing, this study noticed deviations of 4% or less and in the end, it is confirmed that extraction can be achieved with no more than one correlation formula. (3) When only the shape factor and nothing else is used for finding a correlation formula, the formula with a deviation of approximately 5% or less is what one would expect. (4) Since the study observed slight differences in bearings depending on ranges of the shape factors, it needed to extract a weighted value of each bearing, and learned that the smaller the shape factor, the wider the range of a weighted value. The study now suggests that a follow-up research to extract a simple calculation formula by dealing with all these various inclined angles of shade, solar radiation conditions of each region (the ratio of diffuse radiation to direct radiation and others) as well as seasonal features should be carried out.

실내 차양장치 결합형 창호의 태양열 취득률 평가에 대한 실험적 연구 (A Experiment Study on Performance Evaluation of Solar Heat Gain Coefficient in Glazing with Shading Devices)

  • 김태중;강재식;박준석
    • 한국태양에너지학회 논문집
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    • 제34권5호
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    • pp.89-99
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    • 2014
  • The determination of the solar and thermal performance of fenestration is required for the evaluation of fenestration energy performance, estimating building load. Presently, there exist several methods for determining the thermal transmission(U-value) and solar heat gain coefficient (SHGC) of fenestration system. These method are commonly grouped under calculation or experimental methods. While U-value testing and calculation methods have been long established, SHGC has been evaluated only by the method of calculation under the lack of any established testing method. However, it is difficult to assess the exact SHGC for various types of fenestration with sun-shading or other solar control systems. The purpose of this study was to evaluate the effect of interior venetian blind and roll screen on the SHGC of glazing system. SHGC has been evaluated by the KS L 9107 test method and exiting calculation method for precise comparison of the energy performances of various shading devices. In this research, the test sample consists of three different types of double glazing unit with venetian blind and roll screen. Slat angles of venetian blind were changed to $-45^{\circ}$, $0^{\circ}$, and$-45^{\circ}$. For the roll screen, measurements were taken with the roll screen in the closed position. In result, the venetian blind reduced SHGC by 21.2~28.4% at $45^{\circ}$, when compared to the double glazing unit. The roll screen reduced SHGC by 34.4~41.7% at closed. The differences between the measured and calculated SHGC were found to range between 0.001(0.2%) and 0.047(11.1%) for all test cases. For the cases of venetian blind $-45^{\circ}$, $0^{\circ}$ and $45^{\circ}$, the deviation ratio were 3.6~9.8%, 1.1~2.6%, 4.2~11.1%, respectively. For the case of roll screen, the deviation ratio were 4.1~5.7%.

상대광도 차이에 따른 구상나무 유묘의 생장과 물질생산에 관한 연구 (Studies on Growth and Biomass Production of Abies koreana Seedlings under Different Relative Light Intensity)

  • 조혜경;홍성각;김종진
    • 임산에너지
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    • 제20권2호
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    • pp.58-68
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    • 2001
  • 본 연구는 상대광도 차이에 따른 구상나무(Abies koreana Wilson) 유묘의 생장과 물질생산에 대하여 구명하고자 자연전광이 100, 50, 30, 10% 및 2%로 조절된 피음포지에서 구상나무 5년생 포트묘를 사용하여 24개월간 실시하였으며 다음과 같은 결과를 얻었다. 1. 3회의 수고생장을 측정한 결과, 가장 낮은 생장치를 기록한 2% 처리구를 제외하고 처리구 간에 큰 차이를 보이지 않았다. 2. 근원경생장은 상대광도가 낮아짐에 따라 단계적으로 감소하는 경향이 뚜렷하게 나타났다. 3. 상대적으로 낮은 광도에서 자란 유묘의 다음해 생장시작 시기가 늦어졌으며, 신엽의 갯수 및 신초의 갯수, 신초의 길이도 감소하였다. 4. 지상부와 지하부, 엽중량을 포함한 총 건물생산량은 광도가 감소할수록 점진적으로 감소하였다. 5. 구엽의 건물량에 대한 신엽의 건물량의 비율은 1년간 피음처리한 경우 0.99±0.25∼1.06±0.06으로서 100, 50, 30% 처리구에서 비슷하게 높았고, 10%와 2% 처리구에서 각각 0.60±0.04, 0.52±0.03으로서 그 비율이 상대적으로 낮았다. 2년간 피음처리한 경우에는 0.79±0.04∼1.00±0.03으로서 100, 50, 30, 10% 처리구에서 비슷하였고, 2% 처리구에서 0.29±0.03으로 매우 낮은 비율로 나타났다. 6. T/R율은 1년간 피음처리한 유묘의 경우 3.35±0.33∼4.61±0.25로서 100, 50, 30, 10% 처리구 간에 비슷하였으며, 2% 처리구에서는 7.36±0.15로서 다른 처리구에서보다 높게 나타났다. 2년간 피음처리한 유묘의 T/R율은 상대광도 2% 처리구의 2.01±0.14를 제외하고는 1.76±0.11∼3.12±0.19로서 상대광도가 감소할수록 높게 나타났다.

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년생 및 재배조건이 인삼의 엽형에 미치는 영향 (Effects of Plant Age and Cultural Conditions on Leaf Shape of Korean Ginseng)

  • 이종철;최창렬
    • Journal of Ginseng Research
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    • 제8권2호
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    • pp.178-183
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    • 1984
  • This study was conducted to know the influence of plant age and cultural conditions such as plant population density and light intensity under the shading on the leaf shape of panax ginseng. The result obtained were as follows; 1) Leaf length(L)/maximum width(W) was no difference with different age of over 3-over 3year old plant, but that of 1 or 2-yearold was smaller than those of over 3-year old. The values of L/W showed in the order of 2 or 4,3, 1 or 5 leaflet. 2) Ratios of leaflet area to leaf area were 32.0% in leaflet 3, from 209.% to 27.9% in leaflet 2 or 4, and from 6.5% to 7.1% in leaflet 1 or 5. 3) The coefficients of variability for L/W and ratio of leaflet area to leaf area of leaflet 3 were smallest among leaflets. 4) There were significant differences between largest and smallest leaflet 3, leaf areas and ratio of leaflet 3 area to leaf area in same plant. 5) LW and ratio of leaflet 3 area to leaf area were not affected by plant population density. 6) It showed a tendency that the L/W was increased with increasing the light transmittance rate (LTR). The ratio of leaflet 3 area to leaf area of ginseng grown under 20% LTR was not different comparing to that of plant grown under 5% LTR, but it was significantly increased in plant grown at 100% LTR.

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Competition Responses of Populus alba Clone ‘Bolleana’ to red:far-red light

  • Bae, Han-hong;Kang, Ho-duck;Richard B. Hall
    • Plant Resources
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    • 제7권1호
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    • pp.77-86
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    • 2004
  • The reduced ratio of red:far-red (R:FR) light acts as a measure of the proximity of competitors and plants can detect the potentially competing neighbor plants by perceiving reflected R:FR signals and initiate the response of “shade avoidance” before actual shading occurs. The phytochrome system is responsible for monitoring the changes in the R:FR and initiating the shade avoidance response. The response to low R:FR ratio was studied in a white aspen Populus alba clone ‘Bolleana’ using two filter systems: a clear plastic filter system that allows a R:FR ratio less than 1.0 to pass from adjacent border plant reflection; and a special commercial plastic that blocks FR light and creates a R:FR ratio above 3.0. The reduced R:FR signals enhanced the stem elongation in response to competition at the expense of relative stem diameter growth. Trees grown inside clear chambers were 27 % taller than trees grown inside the FR-blocking filter chambers. Stem taper of clear chamber trees was 16% less than the FR-blocking filter trees. Low R:FR also induced 22% more stem dry weight and 13% greater petiole length per leaf compared to the FR-blocking filter trees. There were no statistically significant differences in leaf area, leaf number increment, and total dry weight between the two light filter treatments.

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