• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.10
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• pp.984-989
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• 2004

Significant air temperature increases in urban areas is well known as the heat island phenomenon in a global scale. Therefore, we propose numerical model in order to analyze quantitative effects of building environmental factors on the heat island phenomenon in urban area. In this paper, thermal property of upper atmosphere is experimentally investigated for Sakae, Nagoya Japan. In conclusion, it was confirmed that the boundary layer of a urban canopy existed near the altitude of 139 m.

• Journal of the Korean earth science society
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• v.26 no.2
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• pp.109-113
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• 2005

In this study, the estimation of the temperature distribution of Jeju Island with coastal ocean derived from the thermal band of Landsat 7/ETM+ of January 6, 2003 was carried out. For the computation of the temperature of the island and the coastal ocean based on the thermal band, we used NASA method wiich is the 8 bit Digital Number(DN) converted into spectral radiance. The computed results showed that the land temperature variations were from 0 to 12 Celsius degrees, and a good agreement with the observation ones based on the method. However, the ocean surface temperature was not much changed ground 15 degree since the water was well mixed between the coastal and the offshore ocean. The interesting results were that the temperature distributions of the southern part(Seogwipo City) of Jeju Island were higher than those of the north one(Jeju City) by more than 2 Celsius degree at the same height although the distance between the Jeju and the Seogwipo is only about 35km in winter season. The reason was found that the solar irradiance intensity of the south part was stronger than the north one by Halla mountain in winter season only. From the results, we found that the seasonal variations of solar irradiation and the height of Mt. Halla were an important role of temperature distribution of Jeju Island.

• Geophysics and Geophysical Exploration
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• v.21 no.4
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• pp.220-230
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• 2018

When thermal conductivity of rock is measured with PEDB (Portable Electronic Divided Bar) in a laboratory, it can be greatly influenced by the change of room temperature. Therefore, measuring the thermal conductivity in a thermo-hygrostat is necessary, where it can remain in its constant temperature and humidity condition. In this study, a system for thermal conductivity measurement in a thermo-hygrostat has been set up and the thermal conductivities for the 45 samples collected from GH3 and GH4 boreholes in Ulleung Island have been measured both in dry and saturated conditions. Also, the correlations between those thermal conductivities, density, and effective porosity have been discussed. As a result of correlation analysis among the thermal conductivity, density, and effective porosity, it showed higher correlation with dry samples than saturated samples. Especially, thermal conductivity ratio between saturated and dry conditions shows very high correlation ($R^2=0.90$) with effective porosity.

• Land and Housing Review
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• v.11 no.3
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• pp.75-82
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• 2020

The urban heat island phenomenon that accelerates global warming has always been controversial when summer heatwaves have occurred since it was first investigated and described by Luke Howard in the 1810s. In Korea, since 2014, government have been interested in Cool Roof and painted white coating on the rooftops of the aging and weak buildings, and the cool roof business has expanded nationwide. However, the roof occupies 20-25% of the entire city surface, much less than 37-45% of the pavement area consisting of roads, parking lots and sidewalks, there is a need to expand the policy of Cool Pavement as a way to reduce the urban heat island phenomenon. Domestic cities are high-rise buildings centered on apartments, and the area occupied by outer walls is larger than that of rooftops compared to foreign low-rise buildings. Therefore, as a way to reduce the urban heat island phenomenon, there is a need for a policy to expand the Cool Roof in buildings and use Cool Wall in parallel. Therefore, this study aims to present the expansion of Cool Wall in buildings and Cool Pavement in urban areas, expanding the installation range of Cool Roof, by comparing and reviewing the thermal characteristics of eco-friendly ceramic coating with excellent thermal proof performance and coatings used for roof waterproofing.

• Journal of the Korean housing association
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• v.25 no.5
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• pp.43-50
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• 2014

This study assesses thermal environment of detached housing area by classifying buildings types with codes based on spatial characteristics and forms of the detached housing area and applying heat island alleviation measures, especially focused on FBCs (Form-Based Codes). We analyzed shapes and materials of outdoor space with 3D-CAD, which can affect the surface temperature of the case studies, focusing on heat island alleviation measures, and performed space design by applying relevant climate factors to a simulation. As to the 3D surface temperature and HIP distribution, low-temperature distribution was shown in the case studies when we applied heat island alleviation measures. FBCs (Form- Based Codes) is being developed for the purpose of creating new urban environment. This study is significant because it pays attention to the effects of surface temperatures on accumulation of sensible heat and reviews heat island alleviation measures with outdoor space shapes/materials in order to lower surface temperatures, aiming at improved pleasantness of the detached housing area.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.1
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• pp.11-18
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• 2000

Taegu is notorious as hot and dry summer among Korea cities. One of the most important goals of the open space planning is to ameliorate urban climate of the city. The objective of this research is to evaluate the thermal mitigation effect of the cool islands in Taegu metropolitan city. Cool islands of this paper includes parks and rivers surrounded by or adjacent to urbanized areas. Based on the analysis of the thermal band of Landsat TM at May 17, 1997, the thermal mitigation effect of open spaces in the city could be summarized as follows ; Kumho river showed the largest mitigation effect in terms of the width of mitigation zone and temperature difference. Evaporation from wide water surface and evapo-transpiration from riparian grass land could bring into results. Significant mitigation effect of parks covered with forest can be observed. The temperature range of such parks were between 19.05$^{\circ}C$ and 19.44$^{\circ}C$ However, the thermal mitigation effect of Dalsung park and Apsan park was insignificant. The small size and high percentage of hard paving of the former and the relative low density of the residential areas adjacent to the latter could be the main reason. In conclusion, the thermal mitigation effect in urban ope spaces could be detectedby the employment of thermal band data of Landsat TM and GIS buffering technique.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.277-279
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• 2003

The study utilizes remote sensing as the main monitoring means. With different spatial high-resolution, multichannel ASTER remote sensing image as the main information in Beijing city zone; with regional border and statistical data as auxiliary factor a study between the thermal space distribution character and the underground medium is analyzed based on the GIS logical algorithm and synthetic analysis technology. Results show thermal forming mechanism and the rule of distribution is mainly related to the underground medium and the change of the city distribution. Different underground medium has different degree and intensity influence on the thermal space distribution. Furthermore, urban greenbelt and water areas can reduce the thermal effect and large-scale greenbelt creates green island effect. In addition, Road net, residential area, population density, heat resources and so on have some positive effect on the thermal distribution, which increase the local temperature and intensity on the other hand. It is important to study the thermal distribution and its related factors, which contributes to the plan, construction and development of the city.

• Korean Journal of Remote Sensing
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• v.37 no.4
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• pp.665-685
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• 2021

This study focused on the a 20-year evaluation of the dynamism of critical thermal anomalies in Busan metropolitan area prompted by unusual infrastructural development and demographic growth rate. Archived Landsat thermal data derived-LST was the major input for UTFVI and hot spot analysis (Getis-Ord Gi^*). Results revealed that the surface urban heat island-affected area has gradually expanded overtime from 23.32% to 32.36%; while the critical positive thermal anomalies (level-3 hotspots) have also spatially increased from 19.88% in 2000 to 23.56% in 2020, recording a net LST difference of > 5℃ between the maximum level-3 hotspot and minimum level-3 coldspot each year. It is been observed that thermal conditions of Busan have gradually deteriorated with time, which is potentially inherent in the rate of urban expansion. Thus, this work serves as an eye-opener to powers that be, to think and act constructively towards a sustainable thermal conform for city dwellers.

• Geophysics and Geophysical Exploration
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• v.19 no.3
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• pp.121-130
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• 2016

Several factors are discussed that should be considered in measuring thermal conductivity of rock cores with a PEDB (potable electronic divided bar) system, which is relatively accurate and easy to operate, and can measure the thermal conductivity of rock cores for various diameters. Then the system is applied to measure thermal conductivity of 70 rock cores from Ulleung Island. Air temperature affects most on the thermal conductivity measurements, so that it is very important to minimize the temperature change during the measurement. Other factors such as the temperature of heat source, averaging time window on the thermal conductivity measurements do not affect much compared to air temperature. Slightly higher thermal conductivity is measured when using the thermal contact paste between the sample and heat source or heat sink. Especially, rock cores with irregular surface showed bigger difference. Repeatability showed less than ${\pm}0.3%$ for standard samples and less than ${\pm}4%$ for rock samples, respectively, when the room temperature changes within $1^{\circ}C$ during the measurements. Thermal conductivity of the rock cores from Ulleung Island roughly increases as depth increases but does not show any dependency on the rock types.

• Korean Journal of Agricultural Science
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• v.37 no.1
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• pp.81-86
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• 2010

The urban thermal environment can be an important index to detect heat island phenomena and manage it to improve urban life quality. Cheongju is a typical plain-city that main part has been formed and developed in lowland. The Mushim stream crosses the city from south to north. We reviewed the use of thermal remote sensing in stream around areas and the thermal environments, focusing primarily on the Urban Heat Island(UHI) effect. The purpose of this study is to determine the relationship between the stream nearby urban area and the stream cooling effect of UHI. The objectives are to determine the usefulness of KOMPSAT-2 bands MS3 and MS4 for vegetation cover mapping, and the usefulness of LANDSAT TM band 6 in identifying thermal environmental characteristics and UHI. Land Surface Temperatures (LST) are retrieved by single-channel algorithm to study the UHI from the 6th band (thermal infrared band) of LANDSAT TM images and thermal radiance thermometer based on remote sensing method and the LST distribution maps are accomplished according to the retrieval results. There is also comparison of satellite-derived and in situ measured temperature. The results indicated that the LST of urban center is higher than that of suburban area, the temperature of mountain and water are the lowest area, so it is clearly proved that there are obvious UHI effects by stream. The surface temperature distribution of Mushim stream is detected $2^{\circ}C$ lower than urban area.