• Journal of the Korean Society of Industry Convergence
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• v.4 no.3
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• pp.319-327
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• 2001

The objective of this study is to clarify the effect of thermal radiation environments on human thermal comfort, depending on different canyon types and surface materials on the human thermal comfort in a housing complex in Pohang city, Korea. For this purpose, the operative temperature and new effective temperature were calculated based on the modified mean radiant temperature of canyon models variated by the existence of direct radiation existence, surface materials, and the width and length of the street spaces in a housing complex. These indices for the canyon have been calculated from the meteorological data of Pohang city, which include air temperature, relative humidity, air velocity, global solar radiation and cloud. And the monthly averages of these climate factors measured at noon have been used. The results are as follows: (1) It is revealed that the short-wave radiosity reached the human body is affected by direct solar radiation and surface materials, and the long-wave radiosity by canyon types. (2) The existence of direct solar radiation, the kinds of surface materials and canyon types affect operative temperature($OT_n$) and new effective temperature($ET^*{_n}$). (3) The analysis of the human heat balance in the canyon indicates that the influence of radiation on human body is marc likely to be affected by the existence of direct solar radiation on human model.

• Journal of Environmental Impact Assessment
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• v.22 no.1
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• pp.19-26
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• 2013

The propose of this study is to analyze the optimum spatial resolution of the urban spatial thermal environment structure and to evaluate of the possibility detection using aerial photographs and thermal satellite images. The proper techniques of the optimum spatial resolution for the urban spatial thermal environment structure were analyzed. Thermal infrared satellite image of Seoul city were used for the change rate of surface temperature variation and suggested to the spatial extent and effects of urban surface characteristics and spatial data was interpreted as regions. To extract the surface temperature, Landsat thermal infrared satellite image compared with an automatic weather station data and in the field of the measured temperature and surface temperature by thermal environment affects, the spatial domain has been verified. The surface temperature of the satellite images to extract after adjusting surface temperature isotherms were constructed. The changes in surface temperature from 2008 to 2012 the average surface temperature observation images of changing areas were divided into space. The results of this study are as follows: Through analysis of satellite imagery, Seoul city surface temperature change due to extraction comfort indices were classified into four grades. The comfort index indicative of the temperature of Gangnam-gu, $23.7{\sim}27.2(^{\circ}C)$ range and Songpagu, a $22.7{\sim}30.6(^{\circ}C)$ respectively, the surface temperature of Yeouido $25.8{\sim}32.6(^{\circ}C)$ were in the range.

• Journal of the Korean housing association
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• v.3 no.1
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• pp.85-92
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• 1992

A floor system have played a major part in the living in Korean house. It is an essential element in the residential houses. Uufortunately, a design method of the floor heating system for the human thereat comfort has not established in Korea system. This paper aims to review the previous researches to find the issue for the futher study of comfort floor heating design. The following results were obtained: 1) Nevins et at conducted experiments on the effect of the comfortable of floor and air temperatures on the psychological responses by a large number of subjects. Its objective was to find the combined condition to obtain thermal comfort for sedentary posture.7here has never been researches regarding a sitting Person on the heated floor. 2) Some investigation in Japan on the effect of floor heating system on a sitting person on the floor have been conducted for these years, but they are net based on the human heat balance but on only psychological responses. 3) Hirayama et al developed an indication method of the effect of heat conduction on the sedentary person.4) There are few researches on the human thermal comfort compared whth indoor environmental researches on mechanical controls in Korea. Thus, the further study on the followings in needed the estimaiing of heat conduction between tile hunman body and a floor, developing an index expressed the combined effect of convection, radiation and conduction and its associated experiments.

• Ecology and Resilient Infrastructure
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• v.3 no.1
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• pp.46-53
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• 2016

This study was conducted to analyze the effect of the different land covers of an urban park (Hyowon park) in downtown Suwon on the urban thermal variations during a hot summer. The effect of the air temperature reduction in the urban park was 4.4%-4.5% for the downtown residence (Maetan-dong). This value was about 0.8% lower than that of the outskirts residence (Sanggwanggyo-dong). The daily mean temperature, daily maximum temperature, summer day and heat wave frequency were measured under the different land covers (cement-block, grass, pine-grass, shading area and mixed forest) showed these values generally decreased under natural land cover types. Daily minimum temperature and tropical night frequency didn't seem to correlate with the land cover types. Means of thermal comfort indices (wet bulb globe temperature, heat index and discomfort index) in the shading area, mixed forest and the pine-grass types were lower than those of cement block and grass types. However the levels of those indices were equal to 'very high' or 'caution' levels in the afternoon (13:00-15:00). In the morning (06:00-08:00), thermal comfort indices of the urban park didn't correlate with land cover types. Therefore, to reduce heat stress and to improve the thermal comfort in urban parks, an increase in the area of natural land cover such as grass, forest and open spaces is required.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.4
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• pp.32-44
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• 2024

This study aimed to analyze changes in temperature and humidity based on the presence of roadside trees (tree, tree + shrub) and their arrangement (single row, double row), and calculate the discomfort index to evaluate the thermal environment. For this, three temperature and humidity observation campaigns were conducted from June to September 2023 in Dalseo-gu and Jung-gu, Daegu. Results from the observation in Dalseo-gu showed that temperature and humidity were inversely related. During the day, areas with roadside trees consistently exhibited lower temperatures than those without trees. This pattern was evident in all observation campaigns. In particular, the temperature difference between the areas increased during peak heat hours (15:00-16:00). Specifically, the average temperatures were lowest in areas with tree + shrub planting, followed by tree-only areas, and highest in areas without trees, showing statistically significant differences. The highest temperatures were observed at night and early morning in areas with trees or tree + shrub planting. Conversely, when calculating the discomfort index, areas with trees and shrubs showed the most favorable thermal comfort. In Jung-gu, nearly all observations indicated that areas with double-row tree-planting had significantly lower temperatures than areas with single-row tree-planting. The discomfort index was also found to be more positive in second-row tree planting areas compared to first-row tree planting areas. By quantitatively analyzing the cooling effect of urban roadside trees and the improvement in thermal comfort, this study provides empirical evidence that can be used to support urban forest projects and related policy implementations.

• KIEAE Journal
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• v.12 no.2
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• pp.65-75
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• 2012

The rapid urbanization caused drastic temperature changes in Korea. Excessive urbanization and development result in unpredictable and abnormal climate change all over the world. These changes are reflected in Korean government policy and research about cities, such that various research endeavors have been undergone recently. There are lots of ways to improve the urban environment; the easiest way to solve the urban heat effect problem is to make green spaces within the city. Even though we can't enlarge green spaces over the city limitlessly, it is desperately need for a methodology to efficiently create green space in limited area. Based on awareness of issues as mentioned earlier, we would like to propose landscaping method that can increase thermal comfort in the same area. For this study, simulating the change of temperature, mean radiant temperature, PMV were done due to number of species planted in apartment complex. To increase the reliability of the simulation, first above all, field measurement for temperature change was performed in apartment complex, where residential building are arranged in the form of ㄷ. And based on this data, Envi-met simulation was performed varying 1-7 kinds of species divided by grass, shrubs, arbor (deciduous, conifers) planted in apartment complex. As a result, there was a change less than $1^{\circ}C$ with the increasing number of species in daytime, but the average radiation temperature about $6-7^{\circ}C$ was reduced. In addition, PMV index was improved by more than 0.5 point. Thermal comfort indicator improved significantly depending on the number of species during the day, on the other hand, there were no significant changes at night. As a consequence, this study has shown that not single-species planting but mixed planting varied the number of species would improve the thermal comfort in the same area of landscaping space at daytime.

• Journal of computational fluids engineering
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• v.10 no.1
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• pp.87-93
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• 2005

Macao, a city with three sides bounded by water, is hot and humid in weather in more than six months of a year. This uncomfortable weather induces the frequency of operating air-conditioners. Choice of location for installation of air-conditioner in a building will affect the performance of cooling effect and thermal comfort on the occupants, which in turn will affect the indoor air quality (IAQ) of the building. In the paper, investigation of distribution on carbon dioxide, room air temperature and velocity, as well as air diffusion performance index (ADPI) of a single bedroom in Macao is studied by using the computational fluid dynamics (CFD) software FLOVENT 3.2. Simulations of locating the air-conditioner at 4 different walls will be done and comparisons and analyses of the results will be performed to decide a proper location for the air-conditioner for obtaining good thermal comfort.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.2
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• pp.1-22
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• 2022

The modification effects of street trees on outdoor thermal comfort in summertime according to tree planting types and road direction were analyzed using a computer simulation program, ENVI-met. With trees, the air temperature and wind speed decreased, and the relative humidity increased. In the case of mean radiant temperature (T_mrt) and human thermal sensation, physiological equivalent temperature (PET) and universal thermal climate index (UTCI), there was a decrease during the daytime. The greatest change among the meteorological factors by trees happened in Tmrt, and PET and UTCI showed similar patterns with T_mrt·The most effective tree planting type on thermal comfort modification was low tree height, wide tree crown, high leaf area index, and narrow planting interval (LWDN). T_mrt, PET and UTCI showed a large difference depending on shadow patterns of buildings and trees according to solar altitude and azimuth angles, and building locations. When the building shade areas increased, the thermal modification effect by trees decreased. In particular, results on the east and west sidewalks showed a large deviation over time. When applying the LWDN, the northwest, west and southwest sidewalks showed a significant reduction of 8.6-12.3℃ PET and 4.2-4.5℃ UTCI at 10:00, and the northeast, east and southeast sidewalks showed 8.1-11.8℃ PET and 4.4-5.0℃ UTCI at 16:00. On the other hand, when the least effective type (high tree height, narrow tree crown, low leaf area index, and wide planting interval) was applied, the maximum reduction was up to 1.8℃ PET and 0.9℃ UTCI on the eastern sidewalks, and up to 3.0℃ PET and 0.9℃ UTCI on the western ones. In addition, the difference in modification effects on T_mrt, PET and UTCI between the tree planting types was not significant when the tree effects were reduced by the effects of buildings. These results can be used as basic data to make the most appropriate street tree planting model for thermal comfort improvement in urban areas in summer.

• Journal of the Korean housing association
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• v.14 no.1
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• pp.19-27
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• 2003

This study aims to survey the living spaces of the welfare facilities for the aged to get the objective relationships between the physical thermal environment and the users' subjective responses. The surveys were made twice in winter and once in summer during 2001 and 2002. An ambient temperature, relative humidity, air velocity, globe temperature were measured as physical elements of thermal environment and the ASHRAE Psychophysical Voting Scale were used as an evaluation index for subjective responses. As the results, the aged respond thermally comfortable, in spite of the differences among important factors such as thermal sensations, humidity sensations and air velocity sensations. Also the physical thermal environmental elements and the subjective responses indices exceed thermal comfort range calculated by PMV(Predicted Mean Vote) and PPD(Predicted Percentage Dissatisfied). It shows that the insulation of walls of the facilities is not enough for heating and cooling seasons, and the indoor environmental control is necessary.

• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.2 s.25
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• pp.5-10
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• 2006

The heavy thermal load to battle tanks can cause electronic components' malfunction and crew to be put out of action. The thermal load is generated from Internal heat sources such as electronic devices installed in the room as well as extremely hot weather. In this study, heat and flow analysis for the cabin room of a battle tank was performed to deal with this thermal problem. This study presented the validation of simulation results in comparison with those of test, the investigation of optimal flow design for effective cooling in cabin room and finally the evaluation of thermal comforts to crew.