• 교육시설
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• 제4권3호
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• pp.31-39
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• 1997

The purpose of this study was to improve the lighting environment of the VDT workspaces in computer laboratory. This study was carried out through the field measurements on the computer laboratory and a survey using the questionnaire about the VDT workspaces. The major findings of the study were as follows: (1) It was unbalanced among the illumination, luminance, and color distributions in the the VDT workspaces. (2) The difference of brightness between the CRT screen and its surroundings have presented on the whole unbalanced. (3) It was proved that the artificial light source of the ceiling lighting should use the parabolic louver luminaire limiting the radiant luminance.

• KIEAE Journal
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• 제9권6호
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• pp.45-50
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• 2009

Nowadays, the lighting of urban nightscape has become important for improvement in city. Lighting the outdoor is different that lighting an interior. Outdoor lighting designs should be designed to minimize glare, light trespass, light clutter and energy conservation to avoid light pollution. Mokpo city launched into a large scale project of the city beautification using outdoor lighting. However, outcomes of outdoor lighting project have faced strong opposition from environmental groups. This study aims to analyze the light pollution of outdoor lighting in Mokpo-si for creating a health night environment. The Radiant Imaging Prometric-1400 was used to measure the luminance of Yudal Mountain, Goha Island and Luminarie Street. The result showed that the all the outdoor lighting produce light pollution and some places like mountain and island did not need a lot of lighting all the time.

• 대한설비공학회지:설비저널
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• 제12권3호
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• pp.189-197
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• 1983

In this study, the thermal environment of a certain building was investigated by using of concerned equipments and enquete sheets. The measured items were temperature, humidity, air flow and radiant heat, and thermal responses for the occupants were checked also, which are oriented to be used as basic data for environmental design. The results of this study are as followed. 1. The optimal room temperature was $24\~26.5^{\circ}C$ DBT in cooling season. 2. Under the condition from $50\%\;to\;70\%$ of relative humidity, the difference of relative humidity did not impact upon the feeling temperature. 3. In cooling season, the average clothing factor of occupants was 0.34 clo ; 0.49 clo for men and 0.25 clo for women. 4. The average working factor of occupants was $1.1\~1.3\;Met$ in that cooling season.

• 한국환경복원기술학회지
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• 제26권1호
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• pp.47-59
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• 2023

Due to climate change and urbanization, abnormally high temperatures and heat waves are expected to increase in urban and deteriorate thermal comfort. Planting of street trees and changing the albedo of urban surfaces are the strategies for mitigating the thermal environment of urban, and both of these strategies affect the exposure and blocking of radiative fluxes to pedestrians. After measuring the shortwave and longwave radiation according to the ground surface with different albedo and the presence of street trees using the CNR4 net radiometer, this study analyzed the relationship between this two strategies in terms of thermal environment mitigation by calculating the MRT(Mean Radiant Temperature) of each environment. As a result of comparing the difference between the downward shortwave radiation measured under the right tree and at the control, the shortwave radiation blocking effect of the tree increased as the downward shortwave radiation increased. During daytime hours (from 11 am to 3 pm), the MRT difference caused by the albedo difference(The albedo of the surfaces are 0.479 and 0.131, respectively.) on surfaces with no tree is approximately 3.58℃. When tree is present, the MRT difference caused by the albedo difference is approximately 0.49℃. In addition, in the case of the light-colored ground surface with high albedo, the surface temperature was low and the range of temperature change was lower than the surrounding surface with low albedo. This result shows that the urban thermal environment can be midigate through the planting of street trees, and that the ground surface with high albedo can be considered for short pedestrians. These results can be utilized in planning street and open space in urban by choosing surfaces with high albedo along with the shading effect of vegetation, considering the use by various users.

• KIEAE Journal
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• 제8권6호
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• pp.21-26
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• 2008

According to the tendency of energy efficiency and environment-friendly chracteristics, demend of High-efficiency lighting using LED(Light Emitting Diode)are being increased actively and applied in various fields. However, In order to adequate application of LED light sources, it is necessary to lighting environment and luminous characteristics of LED light sources. This Study aims to characterize the work-plane lighting environment by LED light sources comparing with fluorescent light sources which are widely used. For the sake of this study, a fluorescent light source and 5 LED light sources were introduced and luminance and correlated color temperature were measured to evaluate luminance contrast. The experimental model is Mock-up which is $4.9m{\times}7.2m$ with a height of 2.9m. The test room was set up partition and desks. Luminance and correlated color temperature were measured work-plane on the desk which was set up local lighting by the Radiant Imaging ProMetric 1400. The optical characteristics data of LED can give a lot of advantages to design LED lighting appliances. Hereafter, the object of research will be conducted to evaluate effects of LED light sources on working performance, survey of visual performance, preference and physiology of subjects.

• 한국태양에너지학회 논문집
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• 제26권4호
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• pp.109-118
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• 2006

The tree is regarded as an sustainable architectural outdoor design element which reduce urban heat island effect by its solar shading and evapotranspiration. This study carried out field observations of measuring thermal environment of selected tree and its ambience to determine passive cooling effects. Results from the field observations are as below; Tree-shading effect to the thermal environment can not be properly evaluated by merely measuring air temperature differences between tree-shaded space and unshaded space for the maximum temperature difference is less than $1.5^{\circ}C$. The differences of longwave radiation and shortwave radiation between tree-shaded space and unshaded space are measured. Shortwave radiation is considered as a main thermal comfort determining factor for the difference of the shortwave radiation is much bigger than that of longwave radiation. By thermal infrared image analysis, the surface temperature of the tree under strong solar radiation is measured same as ambient air temperature. By which the evapotranspiration is considered to retard tree surface temperature raising effectively.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.475-479
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• 2012

Thermal energy storage (TES) systems using Microencapsulated phase change material (MPCM) have been recognized as one of the most advanced energy technologies in enhancing the energy efficiency and sustainability of buildings. We examined a way to incorporate MPCMs with building materials through application for wood-based flooring. Wood-based flooring is commonly used for floor finish materials of residential buildings in Korea. However, wood-based flooring has not performed the characteristic of heat storage. This study is aimed at manufacturing high thermal efficiency wood flooring by increasing its heat storage using MPCM. As a result, this study confirmed that MPCM is dispersed well in adhesive through the scanning electron microscopy analysis. From the differential scanning calorimetry analysis, it can be confirmed that this composite has the characteristic of a thermal energy storage material. Also, we analyzed how this composition was formed by physical combination through the Fourier transform infrared analysis. Also, we confirmed the bonding strength of the material by using the universal testing machine.

• 한국태양에너지학회 논문집
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• 제27권4호
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• pp.137-146
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• 2007

This study is about the passive cooling effects of three outdoor solar shading facilities as trees, pergola with wistaria vine and membrane shading structure, which are expected to provide cool spots in the summer. Field observations of measuring thermal environment of selected facilities is executed. Thermal environment measuring was categorized as short wave radiation, long wave radiation, net radiation, globe temperature, surface temperature measured by infrared camera. Heat transfer mechanism is analyzed with overall data from field measurement. Results from this study are as below; 1) Radiation balance measured on shaded surface under membrane shading structure was 17%($86W/m^2$) of the unshaded surface radiation balance($511W/m^2$). 2) Surface temperature comparison between vegetation and membrane of the shading structure is performed at 3 o'clock in the afternoon. Surface temperature of vegetation was same as air temperature and that of membrane was $5^{\circ}C$ higher than air temperature. Vegetation transpiration is considered as the causing factor which make those differences. 3) Results from this study could be used as fundamental data for reducing heat island phenomena and continuos research on this subject would be needed.

• KIEAE Journal
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• 제10권1호
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• pp.19-24
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• 2010

Modern people are spending most of time in interior area. Indoor air environmental problem is one of the most effective factors influenceable to human health. Furthermore, saving energy and making ventilation system for pleasant indoor environment are necessary when it is faced shortage of energy over the world. In our country's case, it is already imposed that required quantity of air ventilation in buildings is 0.7 times per hour on "The regulation on building engineering system". As on the rise of the interests about Indoor air environment, Heat and Carbon dioxide emissions from User's metabolism, activity, furniture, and construction materials etc. could be the causes of Indoor air pollution. If these materials stays in Indoor air for so long, it could directly influence the user's health condition with a disease. As of building's sterilization improved that raised more mechanical ventilation. It also leads much energy waste in a period of high price of fossil fuel. Therefore, the way that saves energy and effective control of indoor ventilation is urgently needed. So, this study places the purpose on validating volume of indoor ventilation and user's comfortable degree by comparison CO2 emission rate through changing floor temperature.

• 한국가스학회지
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• 제20권5호
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• pp.17-26
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• 2016

현대 화학플랜트 및 석유 가스 산업 시설은 다양한 잠재위험으로 인하여 위험물질의 누출 및 화재가 빈번히 발생하고 있다. 그 중 특히 화재는 직접적인 화염의 접촉 또는 복사열로 인하여 인명피해는 물론 건물, 설비에 대한 피해 발생으로 domino effect가 발생하여 2차, 3차 피해까지도 발생하기도 한다. 따라서 본 연구에서는 발생가능한 화재를 파악하여 사고피해영향과 빈도를 낮추어 화재 위험성을 관리하는 FRA(Fire Risk Assessment)기법의 절차를 제시하였으며, 사고피해영향으로 화염의 직접적인 접촉과 복사열로 인한 주요건물(제어실, 창고, 변전소)의 물리적 특성이 변형되는 시간을 고려하였다. 사례연구를 통하여 수행한 FRA기법으로 국내외 화학공장의 위험성을 경감시킬 수 있었으며, Protection 설정을 통한 사고의 빈도와 피해영향의 감소를 정량적으로 파악할 수 있었다.