• 설비공학논문집
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• 제17권10호
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• pp.891-897
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• 2005

The characteristics of energy Performance for total heat exchanger have been investigated under various conditions. In cooling operation the latent and enthalpy efficiency are affected by the difference of absolute humidity ratio between indoor and outdoor air. In addition to this the characteristics of absorbing material in the element affects the energy performance. Low dry bulb temperature of indoor air or high absolute humidity ratio in outdoor air give high latent and enthalpy efficiency even with the same temperature difference of dry bulb temperate between indoor and outdoor air.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.988-992
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• 2006

In recent semiconductor manufacturing clean rooms, air washers are used to remove airborne gaseous contaminants such as $NH_3,\;SO_x$ and organic gases from outdoor air introduced into clean room. Meanwhile, there is a large quantity of exhaust air from clean room. It is desirable to recover heat from exhaust air and use it to reheat outdoor air. In the present study, an experiment was conducted to investigate the heat recovery and gas removal efficiencies of a direct atomization type heat recovery air washer.

• 설비공학논문집
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• 제29권6호
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• pp.289-296
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• 2017

This study aimed to analyze the deck floor heating system of an outdoor swimming pool in terms of the thermal capacity/output and the surface temperature distribution based on the outdoor temperature, to design for anti-freezing during winter. Through the transient heat transfer simulation with PHYSIBEL and theoretical equations, the surface temperature distribution of the floor heating system at two outdoor conditions in Jeju, were calculated and evaluated. The results indicate that the specific thermal output required for maintaining $4^{\circ}C$ surface temperature at the design outdoor temperature of $0.1^{\circ}C$, was about $90W/m^2$. This performance analysis can be applied for future design criteria, including optimizations of system capacity and size.

• 설비공학논문집
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• 제15권6호
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• pp.489-494
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• 2003

"Anmadang" of traditional Korean house is an empty space, surrounded by buildings shaped like the letter, ‘ㅁ’.‘ㅁ’shaped traditional Korean house provides much more comfortable outdoor space for various activities than ‘ㅡ’shaped traditional Korean house. In this paper it has been tried to analyse the dry bulb temperature condition of indoor and outdoor space through measurement of dry bulb temperature in Anmadang, Maru and outdoor space. This paper also analyses the correlation of dry bulb temperature between Anmadang and outdoor space with seasonal variations in traditional Korean houses.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.393-398
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• 2006

This study is undertaken to evaluate the characteristics of cross contamination around exterior air-vents. A CFD analysis has been performed to calculate the cross contamination index for five exterior air-vents sizes according to the outdoor air velocity and separation distance of it. From the result of the numerical method, As the outdoor air velocity is increased, the cross contamination index is increased. on the contrary, as the separation distance of exterior air-vents is increased, the cross contamination index is decreased, additionally the cross contamination is affected by the aspect ratio of the size of exterior Air-vents.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.333-337
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• 2003

The use of reactive shearing structural intensity to place small patches of constrained layer damping material in order to achieve the largest reduction in the radiated sound power of Air-conditioner outdoor unit is described. The normal surface velocity of each panel was measured using a laser doppler vibrometer. Experimental results indicated that patches of constrained layer damping material placed over areas of high reactive structural intensity reduced the radiated sound power significantly more than patches of the same area placed over areas of low reactive structural intensity

• 한국주거학회논문집
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• 제15권1호
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• pp.25-32
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• 2004

The purpose of this study is to understand the indoor thermal environment in the earth brick wall building what is called a ecological Architecture. To investigate thermal performances of the earth brick walls, it measured indoor and outdoor air temperature, relative humidity, globe temperature and PMV in reference house. The result of this study were summarized as the followings; 1) When the outdoor average air temperature was $21.8^{\circ}$, livingroom was $24.9^{\circ}$, kitchen was $25.1^{\circ}$ and 2nd floor room was $25.6^{\circ}$ at 150 cm height from the floor. 2) Although the average outdoor relative humidity was 78%, the livingroom was 67.5%. 3) As the air temperature difference between at the top and bottom was $0.6^{\circ}$ in living room, this value was below 1 % of PPD by ASHRAE Handbook. 4) Predicted Mean Vote(PMV) by ISO-7730 was +0.41.

• 설비공학논문집
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• 제13권11호
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• pp.1165-1173
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• 2001

The objectives of this study are to analyze the application of radiant floor cooling and to evaluate the control methods through experiments when the radiant heating system is used for cooling. Through the experiment analysis the control methods such as on/off control, variable flow control and outdoor reset with indoor temperature feedback control are evaluated and compared. The cooling curve (reset ratio) is found for radiant cooling, which shows tole relation between outside air temperature and supply water temperature. Comparison of cooling methods shows that outdoor reset with indoor temperature feedback control is more appropriate than on/off control and variable flow control with regard to prevention of the condensation and thermal comfort.

• Journal of Preventive Medicine and Public Health
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• 제27권1호
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• pp.59-73
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• 1994

The purpose of this study is to experiments the environmental conditions and the adaption of the human body in the vinyl house. The study was done in spring and winter and experimental clothes were used working clothes in the vinyl house. The results are as follows. 1. Environmental Conditions In the spring season, the indoor air temperature was $27.4{\pm}3.7^{\circ}C$ and the outdoor air temperature was $14.4{\pm}2.7^{\circ}C$. In the winter season, the indoor air temperature was $18.3{\pm}4.8^{\circ}C$ and the outdoor air temperature was $7.6{\pm}2.5^{\circ}C$ on the average. 2. Skin Temperature In the spring season, the mean skin temperatures indoor and outdoor were $33.81{\pm}0.7^{\circ}C\;and\;31.57{\pm}0.8^{\circ}C$ respectively, a difference of $2.24^{\circ}C$. In the winter season, they were $31.95{\pm}1.93^{\circ}C\;and\;29.86{\pm}0.55^{\circ}C$ respectively, a difference of $2.09^{\circ}C$. 3. Clothing Climate In the spring season, the temperature and humidity in the inner layer of clothing were $34.77{\pm}0.80^{\circ}C\;and\;70.75{\pm}1.65%$ indoor, $31.9{\pm}0.52^{\circ}C\;and\;51.9{\pm}3.70%$ outdoor respectively. In the winter season, those were $32.52{\pm}1.04^{\circ}C\;and\;64.65{\pm}3.68%$ indoor, $30.27{\pm}0.96^{\circ}C\;and\;45.07{\pm}2.68%$ outdoor respectively. 4. Physiological Factors Body temperature increased slightly and the pulse rate also rises, but blood pressure decreased a little with the rise of environmental temperature both in the spring and winter seasons. 5. Psychological Factors Thermal sensation in the spring season was expressed as 'slightly warm' or 'warm' indoor and as 'neutral' in the open air, while in the winter it was expressed as 'neutral' or 'slightly warm' outdoor the house and as 'cold' in the open air. Comfort sensation was characterized as 'uncomfortable' or 'slightly uncomfortable' indoor both in the spring and winter seasons, but in the open air it was characterized as 'comfortable' in the spring and as 'slightly uncomfortable' in the winter.

• 한국산업보건학회지
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• 제30권2호
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• pp.163-173
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• 2020

Objectives: The study was evaluated exposure variation and daily absorption level of cadmium, lead concentration of ambient air of monthly data from 1999 to 2017 for main exposure factor in outdoor workers. Methods: Based on the monthly data from 'The annual report of air quality in Korea from 1999 to 2018' in 'Air Korea' website in the Korean Ministry of Environment. The monthly data of PM_2.5, PM₁₀, cadmium, lead concentration of ambient air were recalculated to average, minimum, and maximum. And these data were combined to Asian-dust exposure data from 'The annual report of Asian-dust·smog in 2017' of National Institute of Meteorological Sciences in Korea. Results: Geometric mean(minimum-maximum) concentration in ambient air of monthly data were 0.0017 (ND-0.2015) mg/㎥ in cadmium and 0.0467(ND-0.8554) mg/㎥ in Pb from 1999 to 2017. Both of Cd and Pb concentration in ambient air showed the highest concentration in January and the lowest in August among annual variation from 1999 to 2017. PM₁₀ and PM_2.5 level showed the highest in March(PM₁₀) and February (PM_2.5) the lowest in August both of PM₁₀ and PM_2.5. Discussion: Based on exposure data and prior reports, daily Cd absorption was estimated to 0.013(ND-1.511) mg/day from respiration and 1.89 mg/day from daily food(25.2 mg/day of daily Cd intake). In case of Pb, daily absorption was estimated to 0.350(ND-6.416) mg/day from respiration and 1.38-1.71 mg/day from daily food intake. Conclusion: Cd and Pb with Asian-dust have high influential factor to increase the Cd and Pb exposure at Winter and Spring season in outdoor workers.