• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.5
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• pp.836-847
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• 2022

This study establishes basic data for the development of a new Chemical, Biological, and Radioactive (CBR) protective clothing by selecting the ventilation position to optimize thermal comfort on the basis of the opening and closing of each part. Participants were eight men in their 20s who had previously worn CBR protective clothing. After vigorous exercise and perspiration, the microclimate of the clothing and skin temperature was measured. Results revealed that when the ventilation zipper was opened after exercising, the skin and clothing microclimate temperatures, which had increased during the exercise, decreased in the chest and shoulder blade regions. The clothing microclimate humidity decreased in the chest area. The change was greatest in the chest region; the skin temperature decreased by 0.2℃, the clothing microclimate temperature by 2.7℃, and the clothing microclimate humidity by 3.2%RH through ventilation. Thus, the opening that allows the exchange of accumulated heat and moisture while wearing the CBR protective clothing is efficient.

• Journal of the Korea Fashion and Costume Design Association
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• v.25 no.3
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• pp.53-67
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• 2023

Blood circulation is one of the most important life support functions of our body. It is essential to maintain healthy blood circulation as problems with blood circulation can lead to numerous diseases and serious complications. This study developed women's leggings with gradual compression and soft surface heating functions to improve blood circulation, and evaluated their performance and wearability. A silicon print pattern was developed to provide gradual compression, and a flexible heating surface coated with MWCNT (multi-walled carbon nanotube) conductive ink was fabricated for comfort and thermal effect. For the design, incision lines and materials were applied in consideration of aesthetic aspects, and design lines and colors were altered using a 3D program. The developed leggings showed that blood circulation can be improved when gradual compression and heating functions are simultaneously applied. Results were confirmed through measurements of clothing pressure, blood flow, and surface temperature. In the subjective wearability evaluation, it was confirmed that wearers felt gradual pressure, and they showed high satisfaction with wearability and design.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.12
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• pp.1098-1125
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• 2000

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 1998 and 1999 has been done. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environment. The conclusions are as follows. 1) A review of the recent studies on fluid flow, turbomachinery and pipe-network shows that many experimental investigations are conducted in applications of impingement jets. Researches on turbulent flows, pipe flows, pipe-networks are focused on analyses of practical systems and prediction of system performance. The results of noise reduction in the turbomachinery are also reported. 2) A review of the recent studies on heat transfer analysis and heat exchanger shows that there were many papers on the channel flow with the application to the design of heat exchanger in the heat transfer analysis. Various experimental and numerical papers on heat exchanger were also published, however, there were few papers available for the analysis of whole system including heat exchanger. 3) A review of the recent studies on heat pump system have focused on the multi-type system and the heat pump cycle to utilize treated sewage as the heat source. The defrosting and the frosting behaviors in the fin-tube heat exchanger is experimentally examined by several authors. Several papers on the ice storage cooling system are presented to show the dynamic simulation program and optimal operation conditions. The study on the micro heat pipes for the cooling of high power electronic components is carried out to examine the characteristics of heat and mass transfer processed. In addition to these, new type of separate thermosyphon is studied experimentally. 4) The recent studies on refrigeration/air conditioning system have focused on the system performance and efficiency for new alternative refrigerants. New systems operating with natural refrigerants are drawing lots of attention. In addition to these, evaporation and condensation heat transfer characteristics of traditional and new refrigerants are investigated for plain tubes and also for microfin tubes. Capillary tubes and orifice are main topics of research as expansion devices and studies on thermophysical properties of new refrigerants and refrigerant/oil mixtures are widely carried out. 5) A review of the recent studies on absorption cooling system shows that numerous experimental and analytical studies on the improvement of absorber performance have been presented. Dynamic analysis of compressor have been performed to understand its vibration characteristics. However research works on tow-phase flow and heat transfer, which could be encountered in the refrigeration system and various phase-change heat exchanger, were seemed to be insufficient. 6) A review of recent studies on duct system shows that the methods for circuit analysis, and flow balancing have been presented. Researches on ventilation are focused on the measurement of ventilation efficiency, and variation of ventilation efficiency with ventilation methods by numerous experimental and numerical studies. Furthermore, many studies have been conducted in real building in order to estimate indoor thermal environments. Many research works to get some information for cooling tower design have been performed but are insufficient. 7) A review on the recent studies on architectural thermal environment and building mechanical systems design shows that thermal comfort analysis is sitting environment, thermal performance analysis of Korean traditional building structures., and evaluation of building environmental load have been performed. However research works to improve the performance of mechanical system design and construction technology were seemed to be insufficient.

• Journal of Environmental Impact Assessment
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• v.30 no.2
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• pp.105-116
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• 2021

In the city of high population density crowded with buildings, Urban Heat Island (UHI) is intensified, and the city is vulnerable to thermal comfort. The maintenance of vacant land in downtown is treated as a factor that undermines the residential environment, spoils the urban landscape, and decreases the economic vitality of the whole region. Therefore, this study compared the effects on microclimate in the surrounding area according to the development scenarios targeting the vacant land in Songhyeon-dong, Jongno-gu, Seoul. The status quo, green oriented, building oriented and green-building mediation scenarios were established and ENVI-met was used to compare and analyze the impact of changes in wind speed, air temperature and mean radiant temperature (MRT) within 1 km of the target and the target site. The result of inside and 1 km radius the targeted area showed that the seasonal average temperature decreased and the wind speed increased when the green oriented scenario was compared with the current state one. It was expected that the temperature lowered to -0.73 ℃ or increased to 1.5 ℃ in summer, and the wind speed was affected up to 210 meters depending on the scenario. And it was revealed that green area inside the site generally affects inside area, but the layout and size of the buildings affect either internal and external area. This study is expected to help as a decision-making support tool for developing Songhyeon-dong area and to be used to reflect the part related to microclimate on the future environmental effects evaluation system.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.3 s.151
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• pp.407-411
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• 2006

This study was carried out to investigate the physiological responses of obese children after a short-term wear training and education. A ten-week program was conducted on thirteen obese elementary school children of six boys and seven girls in the 4th to the 6th grade. During the program, the children were instructed to measure daily ambient temperature and weight of their clothing. Physiological responses of the sedentary children in 100$\%$ cotton short sleeved t-shirt (0.13clo) and T/C short pants(0.09clo) were observed in the climatic chamber of 23.0$\pm$0.5$^{circ}C$ and 50$\pm$5$\%$RH before and after program. During the experiment, internal ear temperature ($T_{ear}$), seven site skin temperatures, systolic blood pressure, diastolic blood pressure, heart rate, and subjective responses of thermal comfort and thermal sensation were measured every 5minutes. Mean skin temperature($T_{sk}$) and mean arterial pressure(MAP) were calculated. Obtained data are statistically analyzed and main results are as follows. There was highly significant correlation between the ambient temperature and the total clothing weight. $T_{ear}$ and MAP were reduced in the post-program compared to the pre-program. The obese girls felt slightly warmer than the obese boys and the girls were likely to prefer lower ambient temperature in the post-program than the pre-program. It was concluded that the 10 week wear training is apt to be more applicable to the obese girls than the obese boys. However, a more comprehensive study including. diverse measurements of deep body temperature with a long-term training would be needed to clarify the improvement of temperature adaptability in the obese children.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.1
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• pp.93-106
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• 2016

This study aimed to estimate and evaluate the thermal mitigation of the urban tree canopy on the summer outdoor environment by quantitative use of mean radiant temperature. This study applied the SOLWEIG model based $T_{mrt}$ comparison method by using both (1) urban tree canopy presence examples and (2) urban tree canopy absence examples as constructed from airborne LiDAR system based three-dimensional point cloud data. As a result, it was found that an urban tree canopy can provide a decrease in the entire domain averaged daily mean $T_{mrt}$ about $5^{\circ}C$ and that the difference can increase up to $33^{\circ}C$ depending both on sun position and site conditions. These results will enhance urban microclimate studies such as indices (e.g., wind speed, humidity, air temperature) and biometeorology (e.g., perceived temperature) and will be used to support forest based public green policy development.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.6
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• pp.121-132
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• 2021

Green facade has a significant impact on building's energy performance by controlling the absorption of solar radiation and improving outdoor thermal comfort through shading and evapotranspiration. In particular, since high-density building does not enough green space, green facade, and rooftop greening using artificial ground plants are highly utilized. However, the level of cooling effect according to plant traits and irrigation control is different. Therefore, in this study, the cooling effect analyzed for a total of 4 cases by controlling the irrigation condition based on hedera and spurge. Although hedera under sufficient water had the highest cooling effect(-2℃~-4℃), had the lowest cooling effect under non-irrigation(+1.1℃~+4.4℃). In addition, hedera under sufficient water had cooling effect than hedera under non-irrigation(-1℃~-8.1℃) and in the case of spurge, it had cooling effect(-0.3℃~-7.8℃) more than non-irrigation. As a result of measuring the amount of transpiration according to the light intensity (PAR) and carbon dioxide concentration conditions, transpiration of hedera was higher than the spurge (respectively 0.63204mmolm^-2s^-1, 0.674367mmolm^-2s^-1). The difference in the cooling effect of the green facade under irrigation condition was significant. But the potential cooling effect of green facade according to plants species was different. Therefore, in order to maximize and continuously provide the cooling effect of green facade in urban areas, it is necessary to consider the characteristics of plants and the control of water supply through the irrigation system.

• Science of Emotion and Sensibility
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• v.13 no.2
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• pp.359-370
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• 2010

The purpose of this study is to test the performance of the recommended summer dressing for office man through the analysis of skin temperature changes by air-conditioning temperature. We tested two clothing combinations; formal wear with necktie and casual shirts without necktie as for Cool mapsi. 4 male subjects sat to stabilize for thirty minutes after entering artificial-climate chamber with both temperature of $25^{\circ}C$, $27^{\circ}C$ and $50{\pm}10%$ R.H. And during 60 minute experiments of simulating office work, the subjective feelings including thermal, humidity and comfort sensation, skin temperature, clothing humidity and sweat amount were measured at the equal intervals. The result is that formal wear of $25^{\circ}C$ and Cool mapsi of $27^{\circ}C$ show good values such as low skin temperature, low clothing humidity and neutral thermal sensation. And Cool mapsi of $25^{\circ}C$ shows the risk of low rectal temperature for long and static energy level of office work. Formal wear of $27^{\circ}C$ shows high values of mean skin temperature, clothing humidity and thermal sensation. Second experiment was to find the ambient temperature when the subject wearing formal wear shows the skin temperature corresponding to which he shows on Cool mapsi of $27^{\circ}C$. The air-conditioning temperature on wearing formal wear has to be $2^{\circ}C$ lower to produce the corresponding skin temperature to which shows on wearing Cool mapsi of $27^{\circ}C$. Therefore it is possible to increase room temperature to $27^{\circ}C$, when wear Cool mapsi for summer office, for skin temperature and thermal sensation are produced the same.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.7
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• pp.492-507
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• 2010

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2009. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery and piping, and new and renewable energy. Various topics were covered in the field of general thermal and fluid flow such as an expander, a capillary tube, the flow of micro-channel water blocks, the friction and anti-wear characteristics of nano oils with mixtures of refrigerant oils, etc. Research issues mainly focused on the design of micro-pumps and fans, the heat resistance reliability of axial smoke exhaust fans, and hood systems in the field of fluid machinery and piping. Studies on ground water sources were executed concerning two well type geothermal heat pumps and multi-heat pumps in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included the heat transfer in thermoelectric cooling systems, refrigerants, evaporators, dryers, desiccant rotors. In the area of industrial heat exchangers, researches on high temperature ceramic heat exchangers, plate heat exchangers, frosting on fins of heat exchangers were performed. (3) In the field of refrigeration, papers were presented on alternative refrigerants, system improvements, and the utilization of various energy sources. Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and $CO_2$ were studied. Efforts to improve the performance of refrigeration systems were made applying various ideas of suction line heat exchangers, subcooling bypass lines and gas injection systems. Studies on heat pump systems using unutilized energy sources such as river water, underground water, and waste heat were also reported. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. In the area of cogeneration systems, papers on energy and economic analysis, LCC analysis and cost estimating were reported. Studies on ventilation and heat recovery systems introduced the effect on fire and smoke control, and energy reduction. Papers on district cooling and heating systems dealt with design capacity evaluation, application plan and field application. Also, the maintenance and management of building service equipments were presented for HVAC systems. (5) In the field of architectural environment, various studies were carried to improve indoor air quality and to analyze the heat load characteristics of buildings by energy simulation. These studies helped to understand the physics related to building load characteristics and to improve the quality of architectural environment where human beings reside in.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.6
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• pp.521-537
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• 2012

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2011. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of fluid machinery and fluid flow, thermodynamic cycle, and new and renewable energy. Various topics were presented in the field of fluid machinery and fluid flow. Research issues mainly focused on the rankine cycle in the field of thermodynamic cycle. In the new and renewable energy area, researches were presented on geothermal energy, fuel cell, biogas, reformer, solar water heating system, and metane hydration. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer, nanofluids and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer above liquid helium surface in a cryostat, methane hydrate formation, heat and mass transfer in a liquid desiccant dehumidifier, thermoelectric air-cooling system, heat transfer in multiple slot impinging jet, and heat transfer enhancement by protrusion-in-dimples. In the area of pool boiling and condensing heat transfer, researches on pool boiling of water in low-fin and turbo-B surfaces, pool boiling of R245a, convective boiling two-phase flow in trapezoidal microchannels, condensing of FC-72 on pin-finned surfaces, and natural circulation vertical evaporator were actively performed. In the area of nanofluids, thermal characteristics of heat pipes using water-based MWCNT nanofluids and the thermal conductivity and viscosity were measured. In the area of industrial heat exchangers, researches on fin-tube heat exchangers for waste gas heat recovery and Chevron type plate heat exchanger were implemented. (3) Refrigeration systems with alternative refrigerants such as $CO_2$, hydrocarbons, and mixed refrigerants were studied. Heating performance improvement of heat pump systems were tried applying supplementary components such as a refrigerant heater or a solar collector. The effects of frost growth were studied on the operation characteristic of refrigeration systems and the energy performance of various defrost methods were evaluated. The current situation of the domestic cold storage facilities was analyzed and the future demand was predicted. (4) In building mechanical system fields, a variety of studies were conducted to achieve effective consumption of heat and maximize efficiency of heat in buildings. Various researches were performed to maximize performance of mechanical devices and optimize the operation of HVAC systems. (5) In the fields of architectural environment and energy, diverse purposes of studies were conducted such as indoor environment, building energy, and renewable energy. In particular, renewable energy and building energy-related researches have mainly been studied as reflecting the global interests. In addition, various researches have been performed for reducing cooling load in a building using spot exhaust air, natural ventilation and energy efficiency systems.