• Journal of the Ergonomics Society of Korea
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• v.17 no.3
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• pp.41-59
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• 1998

Thermal comfort aspect of a locally-cooled target space in warm and humid environments(typically in the rainy summer season) was studied in view of PPD index. First. theoretical analyses were conducted to examine the effect of the governing parameters(such as air temperature, relative humidity and air velocity, etc.) using a computer model. Secondly, experimental investigations were also performed in a climatic room designed to simulate corresponding thermal conditions of outdoor environments. During the tests, temporal variation of PPD was recorded as functions of climatic variables(outdoor and indoor temperatures, relative humidity and air velocity) for the given human factors(metabolic heat generation and clothing). From both theoretical and experimental investigations, air temperature and air velocity were found to be the most dominant parameters affecting PPD of the target space. Results were summarized as: 1. Relative humidity of the locally-cooled target space tends to approach that of outdoor's as the space is subjected to an ON-OFF mode of cooling, since moisture potential of the two rooms reaches an equalized state as a result of moisture diffusion. 2. It was recognized that changes in relative humidity did not show any significance in view of thermal comfort as was reported in the previous studies, while variations of both temperature and air velocity caused relatively large changes in the degree of thermal comfort. 3. In-door environment should be evaluated in terms of PPD instead of relative humidity commonly recognized as an important climatic variable particularly in warm and humid environments.

• Journal of the Korean Institute of Educational Facilities
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• v.15 no.5
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• pp.13-20
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• 2008

The sense of place at school environment becomes more important as children increasingly spend more time in school and children's attachment to the environment affects the cognition development of children. The goal of this research is to identify characteristics that enhance the sense of place for children in outdoor space and check the possibilities of forming it in the school environments. Through the analysis of design document and design report for schematic design of elementary school which is executed through Korean Institute of Educational Facilities between 2002-2005, 47cases from 32elementary schools are analyzed. As a result it is found that designers tend to orient towards the visual aspects compared to other invisible aspects such as thermal comfort and participation of children, which is extracted as a key characteristics of forming a sense of place for children. More attention is required to enhance the sense of place in school environment to support the child development in everyday space.

• Journal of the Korean Solar Energy Society
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• v.34 no.6
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• pp.27-37
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• 2014

Heat island is caused by changes of land coverage structure of cities and use of energy in buildings. As a result energy use in buildings get to increase further followed by rising of GHG emission and deteriorating climate change. Eco-friendly housing complex is a kind of plan that applies environmental control elements like water and green spaces to housing complex. With these methods, it can be expected to create thermal environment of indoor and outdoor. In this paper quantitative examination is studied on using CFD to find out the effects of river, water permeable, parks and planting on thermal environment. And by comparing field measurements with CFD results which are aimed to development phase housing complex, feasibility and usability of the CFD analysis results are confirmed. And also, analysis on the ventilation performance followed by natural ventilation system is analyzed by selecting one building in housing complex. Based on the results, the possibilities of energy reduction through making thermal environment and applying natural ventilation are studied. With these outcomes, creating thermal conditions and using natural ventilation would be contributed to GHG reduction.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.281-284
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• 2008

The purposes of this study were to make clear the present condition of indoor thermal environment in apartment units and to analyze the relation of the living factors with indoor thermal elements. The field surveys consisted of measurements on physical elements and observations on living factors and interview on resident's subjective responses were carried out in 20 apartment units. The field surveys were carried out during the $January{\sim}March$ 2007. Measuring elements were air temperature, globe temperature, and relative humidity. As results, the averages of indoor temperature each houses were $21.2{\sim}27.2^{\circ}C$, the number of houses exceed the comfort zone were 4. The averages of globe temperature each houses were $21.3{\sim}27.5^{\circ}C$, 6 houses exceeded the comfort zone. The means of relative humidity were $19.5{\sim}58.8%$, relatively dry condition. The clothing value of residents were $0.39{\sim}0.89$ clo(average 0.68 clo). The average of thermal sensation ratings each room were $4.2{\sim}4.8$, 'neutral'$\sim$'slightly warm'. The results of regression analysis on relations of living factors with the thermal elements are as follow; ventilation time(outdoor air exchange), door opening time with balcony, and gas cooker use time had significant effect on indoor temperature.

• Journal of the Korean Solar Energy Society
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• v.40 no.2
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• pp.25-36
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• 2020

The Korean government has a plan to mandate zero-energy buildings in 2020 for public and 2025 for private buildings. In order to design a zero-energy building, insulation and airtightness, which are the most basic elements of passive house technology, are required, and the government has been accomplished this through step-by-step strengthening of related standards. In passive house with high thermal insulation and airtightness performance, the heat introduced into the building through solar radiation can be stored for a long time to keep the inside warm during winter. On the other hand, during summer, heat introduced into the building cannot be easily released to outside, so it is necessary to actively block solar radiation and high temperature outdoor air to prevent an increase of indoor temperature. Therefore, this study aims to derive an appropriate operation condition of passive house to maintain the indoor temperature at an suitable level according to the ventilation methods and solar shading conditions. As a result, under the conditions that the outdoor temperature was 28℃ or less, the ventilation using a heat recovery ventilation system at daytime and natural ventilation at nighttime were selected for the most appropriate operation method. In addition, in the case of solar shading, it was found that blocking solar radiation at daytime using the blind and open the blind at nighttime to ensure natural ventilation were selected for the most appropriate solar shading condition.

• KIEAE Journal
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• v.9 no.4
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• pp.37-42
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• 2009

Photovoltaic-thermal(PVT) collectors are a combination of photovoltaic modules with solar thermal collectors, forming one device that receives solar radiation and produces electricity and heat simultaneously. The PVT collectors can produce more energy per unit surface area than side by side PV modules and solar thermal collectors. There are two types of water type PVT collectors, depending on the existence of glass cover over PV module; glass-covered(glazed) PVT module, which produces relatively more thermal energy but has lower electrical yield, and uncovered(unglazed) PVT module, which has relatively lower thermal energy with somewhat higher electrical performance. In this paper, the experimental performance of two types of the water-based PVT combined collectors, glazed and unglazed, was analyzed. The electrical and thermal performances of the PVT combined collectors were measured in outdoor conditions, and the results were compared.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.8
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• pp.682-691
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• 2001

Most of radiant floor heating systems are operated in the intermittent heating mode in Korea. The application possibility of predictive suboptimal control for Koran residential house was investigated by computer simulation and experiment. For this study, TRNSYS program was used and an experimental facility consisting of tow rooms ($3\times4.4\times2.8 m$) identical in construction was built. The facility enabled simultaneous comparison of two different control method. And real multi residential hose was investigated. Results showed that outdoor air temperature prediction control was superior to the conventional control for radiant floor heating system operated in the intermittent heating mode. New control system resulted in good thermal environment and les energy consumption.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.283-284
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• 2023

Green remodeling of pubic buildings for improving indoor environment and reducing energy consumption is increasingly promoted. The objective of this study is to measure and analyze for wall's thermal performance, thermal transmittance, of existing buildings. The method of this present study refered the ISO 9869-1 and is to measured heat flow, surface temperature of wall, and in/outdoor temperature over 7 days. And it was compared the calculated thermal transmittance with measured one. The measured wall's thermal transmittance value is about two times than the calculated thermal transmittance value.

• Journal of the Korean Solar Energy Society
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• v.26 no.4
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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.

• Journal of the Korean housing association
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• v.19 no.4
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• pp.97-105
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• 2008

The purposes of this study were to determine the actual state of the indoor thermal environment in apartment units and to analyze the relationship between the living factors and indoor thermal elements. The field surveys consisted of measurements of physical elements and observations of living factors. In addition, the residents of 20 apartment units were interviewed to survey their subjective response. Field surveys were carried out from January to March 2007. Measuring elements were air temperature, globe temperature, and relative humidity. The results showed that the average of indoor temperature for the houses was $21.2{\sim}27.2^{\circ}C$, while 4 houses exceeded the comfort zone. The average of globe temperature for the houses was $21.3{\sim}27.5^{\circ}C$, while 6 houses exceeded the comfort zone. The mean relative humidity was $19.5{\sim}58.8%$, which is a relatively dry condition. The residents' average clothing value was $0.39{\sim}0.89$ clo(average 0.68 clo). The average thermal sensation vote on each room was $4.2{\sim}4.8$, which is 'neutral' to 'slightly warm'. Living factors had significant effect on indoor temperature in regression analysis were ventilation time(outdoor air exchange), opening time of door through balcony, and gas cooker use time.