• 한국태양에너지학회 논문집
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• 제31권4호
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• pp.72-79
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• 2011

Solar radiation data are the best source of information for estimating average incident radiation. Lacking this or data from nearby locations of similar climate, it is possible to use empirical relationships to estimate radiation from days of hours of bright sunshine. It is necessary to estimate the regression coefficients in order to predict the daily global radiation on a horizontal surface. Therefore many different equations have proposed to evaluate them for certain areas. In this work a new correlation has been made to predict the solar radiation for 16 different areas over Korea by estimating the regression coefficients taking into account hours of bright sunshine. Particularly, the proposed straight line regression model shows reliable results for estimating the global radiation on a horizontal surface with monthly average deviation of -0.2 to +0.5% and each station annual average deviation of -1.6 to +1.7% from measured values.

• 한국태양에너지학회 논문집
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• 제32권6호
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• pp.44-52
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• 2012

In all building's energy simulation applications, solar radiation must be calculated on inclined surfaces. Various solar radiation models based on measured data of specific region were used in building simulation programs. Therefore, we should choose the appropriate solar radiation model for Seoul. The purpose of this study is to compare four solar radiation models on inclined surfaces that are widely used in building energy simulations. In this case, it can be said the appropriate model in Seoul is the Isotropic model.

• 생물환경조절학회지
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• 제6권3호
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• pp.176-182
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• 1997

온실의 동방위 및 지붕경사각, 구조물의 재원, 설치 지역의 위도 등이 단동형 유리 온실내의 직달 및 산란일사 투과에 미치는 효과를 분석하고자 컴퓨터 시뮬레이션 모형이 개발되었다. 개발된 모형은 년중 일수, 온실의 방위 및 설치된 지점의 윈도, 지붕경사각이 서로 다른 단동 및 연동 온실에 대하여 적용할 수 있다. 본 연구에서 수행된 온실의 동방위가 온실내의 직달 및 산란일사 투과율에 미치는 영향에서 얻어진 결과를 요약하면 다음과 같다. 1. 단동의 유리온실에서 계산된 산란일사의 투과율은 60.4％로서, 동방위에 무관하게 일정한 값을 갖는 것으로 나타났다. 2. 겨울철에 직달일사의 투과율은 동서동에서 67∼69％ 정도이고, 남북동의 경우 51∼55％ 정도로서 동서동에서 14∼16％ 정도 높게 나타났다. 3. 여름철에 직달일사의 투과율은 동서동에 서보다 남북동에서 높게 나타났다. 4. 직달일사의 투과율에 미치는 국내 지역간의 차이는 거의 없는 것으로 나타났다.

• 한국태양에너지학회 논문집
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• 제28권4호
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• pp.17-24
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• 2008

Estimation of typical solar radiation is very important for the calculations concerning many solar applications. But solar radiation measurements are not easily available because of the expensive measuring equipment and techniques required. Accordingly, for regions where no solar radiation is measured, solar radiation need to be estimated using other meteorological data. However, currently in Korea, there is no study on how to do this. In this paper, the global radiation of the six major cities in South Korea where the global radiation is measured using comparatively simple CRM model was calculated compared and analyzed. The comparison between the original coefficient and the site-fitted coefficient for these cities are as follows. Differences between the site-fitted coefficient and the original coefficient for six cities are small. Except for Gwangju, both calculations show strong correlation. In case of Seoul, the $R^2$(coefficient of determination) were 0.747 and 0.749. In case of Busan and Daegu the figures were 0.817, 0.819 and 0.820, 0.821 respectively. For Gwangju, these were 0.618 and 0.622, Thus, the site-fitted coefficients were slightly higher for these four cities. On the other hand, Daejeon and Incheon was reported 0.773, 0.772 and 0.785, 0.783, respectively.

• 한국농공학회지
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• 제45권3호
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• pp.84-93
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• 2003

Photoreactivation of microorganism following UV-disinfection is one of the research topics of interest in assessing the UV-disinfection performance. Apparent photoreactivation was examined under fluorescent lamp and solar radiation as well as in darkness. Total coliform, fecal coliform, and Escherichia coli were used as indicator microorganisms, and their concentration was monitored with time after UV-disinfection. Under the darkness, their initial concentration of 10∼30 MPN/100 mL increased to the level of 100 MPN/100 mL after 24 hours, which implied that part of damaged microorganisms by UV-disinfection might be repairable with time. Under the fluorescent lamp, photoreactivation was more apparent that their concentration increased up to 1,000 MPN/100 mL which might significantly impair the water uses specially in reuse of reclaimed wastewater. However, their concentration further decreased down to below 2 MPN/100 mL under the solar radiation primarily due to additional disinfection by solar radiation rather than photoreactivation. Samples not disinfected by UV-disinfection also demonstrated substantial decrease of their concentration under solar radiation from about 5,000 MPN/100 mL to less than 30 MPN/100 mL in 24 hours. But direct reuse of effluent without disinfection is not recommended because natural decay by solar radiation may take time and be affected by climatic conditions. The result suggests that photoreactivation of pathogenic microorganisms may not be concerned in agricultural reuse of reclaimed wastewater because solar radiation may provide further disinfection after UV-disinfection.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.297-302
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• 2011

In this study, used Trnsys and will apply metropolitan city distinguishes, fixations and BIPV systems the photovoltaic module arrangement environment which receives solar radiation quantity plentifully from the case design process which and most the outcome value simulation did analyzed. The climate data uses each metropolitan city distinguishes 20 average weather data, With measured values of horizontal solar radiation. The error scope appeared with 0.1%~6.7%. Variable of module arrangement Azimuth and angle of inclination of module and comparison group Module on due south direction angle of inclination $45^{\circ}$ day time set with the yearly average solar radiation quantity which receives. The result When the case comparison group which arranges a solar storehouse module with optimum environment and comparing until the minimum 1.4% - maximum 10.9% the solar radiation quantity difference appears with the thing, metropolitan city distinguishes considers the case solar radiation quantity which will arrange a photovoltaic module and that must establish with optimum environment judges.

• 대한원격탐사학회지
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• 제32권3호
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• pp.201-220
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• 2016

본 연구에서는 대기 상단에서 반사된 복사와 지표면에서 흡수된 복사에너지가 서로 선형 관계임을 보인 기존의 알고리즘을 MODerate resolution Imaging Spectroradiometer (MODIS) 관측 자료에 적용시킬 수 있도록 개선하여 하향 및 순 태양 복사에너지를 산출하였다. 비교 검증을 수행하기 위해 Clouds and the Earth's Radiant Energy System (CERES) 센서와 강릉원주대학교(GWNU), 미국의 Atmospheric Radiation Measurement (ARM) 관측소의 지상 일사계 자료를 사용하였다. 지구 에너지 수지와 관련하여 지표면에서의 복사에너지를 비교하기에 앞서 알고리즘을 통한 산출 결과와 CERES 자료의 대기 상단 복사에너지를 비교한 결과, 결정계수가 0.9이상을 보여 상당히 유사함을 보였지만 Root-Mean-Square-Deviation (RMSD) 값이 다소 차이가 있는 것으로 나타났고 하향과 순 태양 복사에너지도 비슷한 결과를 얻었다. 강릉원주대학교 자료와 비교한 결과, 본 연구의 알고리즘을 통해 산출된 결과가 CERES 자료보다 작은 RMSD를 보임으로서 더 높은 정확도를 보였다. 한편, ARM 관측소의 경우 하향 태양 복사에너지의 평균적인 RMSD가 CERES 자료에 비해 다소 크게 산출되었지만 순 태양 복사에너지의 경우 비슷한 결과가 나타났으며 시 공간 해상도를 고려하였을 때 상당히 유사한 경향을 보이고 있음을 확인하였다. 본 연구에서 파악된 문제점에 대한 개선을 통해 향후 지상 관측을 대신하여 위성 관측으로부터 지표면에서의 하향 및 순 태양 복사에너지 자료를 고해상도로 제공하는데 유용하게 활용될 수 있을 것으로 기대된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 제17회 워크샵 및 추계학술대회
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• pp.595-598
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• 2005

The thermal performance of glass evacuated tube solar collectors are numerically and experimentally investigated. Four different shapes of solar collectors are considered and the performances of these solar collectors are compared. Dealing with a single collector tube, the effects of not only the shapes of the absorber tube but also the incidence angle of solar irradiation (beam radiation) on thermal performance of the collector are studied. However the solar irradiation consists of the beam radiation as well as the diffuse radiation. Also, the interference of solar irradiation and heat transfer interaction between the tubes exist in an actual solar collector. These effects are considered in this study experimentally and numerically the accuracy of the numerical model is verified by the experimental results. The result shows that the thermal performance of the absorber used a plate fin and U-tube is the best.

• Journal of Advanced Marine Engineering and Technology
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• 제37권7호
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• pp.799-806
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• 2013

As a first step to develop the hybrid power generation system, on this study, the time-variable resources of wind and solar radiation of Yeongdo, Busan, Korea had been measured during June and July 2013. And the quantity of generated wind power and solar photovoltaic had also been measured during the same period. It is found out that the wind mainly flew from southwest at the average speed of 2 m/s during 2 months. And it is clear that, because of the low wind velocity, the wind quality to generate the power seems not enough at this area. Meanwhile solar radiation was measured every daytime (6:00~19:00) and the peak solar radiation occurred around 12:00~14:00. And it is clear that the time-based variations of quantity of generated power were proportional to the variations of these resources, respectively. As a proposal, these 2 natural energies can be combined as resources of a hybrid system, because these 2 patterns are not overlapped so much on time base.

• 한국태양에너지학회 논문집
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• 제29권2호
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• pp.47-54
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• 2009

The amount of incident rays over inclination according to direction has been widely utilized as important data m installing solar thermal systems. To optimize the incident solar radiation, the slope, that is the angle between the plane surface in question and the horizontal, and the solar azimuth angles are needed for these solar thermal systems. This is because the performance of the solar thermal systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized solar thermal systems will be provided for designers and employees working in the solar collector related industries.