• Title/Summary/Keyword: outdoor temperature

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Influence of Seasonal Variation on Basal Metabolic Rates on Thermal Environments & Clothing Weight (생활환경온도와 착의량이 기초대사에 미치는 영향)

  • 이원자;침규남;김진선;박승순
    • The Research Journal of the Costume Culture
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    • v.8 no.3
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    • pp.374-386
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    • 2000
  • This study investigated the relation between seasonal variation of total clothing weight, room, outdoor temperature and basal metabolic rate in man. The basal metabolic rate and total clothing weight, room temperature was determined seasonal for a period of two years and grouped four seasons. Subjects (adults volunteers) who live in seoul and mokpo were compose 120 subject The results were obtained as follows. Seasonal outdoor temperature was difference of seoul and. mokpo. But room temperature in apartments was a little difference than private house. Total-clothing weight is showed seasonal variations at the seoul, private house than at the mokpo, apartment.. The basal metabolic rate is suggested there in gender difference in the basal metabolic rate (P〈.001). The basal metabolic rate increased gradually with the peak of winter sespectively and deceased again todward summer. The difference of between basal metabolic rate in summer and winter was significant room temperature, of seoul and private house, and light total clothing weight.

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The Variation of Top Floor Indoor Thermal Environment with Roof Storage Using Model Experiment (옥상 저류조 설치에 따른 최상층 실내열환경 변화에 관한 모형 실험연구)

  • Park, Bong-Gil;Lee, Kyung-Hee;Jang, Seung-Jae
    • Journal of the Korean housing association
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    • v.20 no.3
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    • pp.105-112
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    • 2009
  • The purpose of this study is to investigate a top floor, indoor, thermal environment by comparison between the indoor air temperature and the rooftop surface temperature, and between the indoor air temperature and the outdoor air temperature using an experimental model. The model experiment was conducted with 4 cases,: no-rainfall, 1 em-height, 10 em-height and 20em-height of rainfall on the rooftop. According to the results of the height of stored rainfall, the average air temperature difference between the indoor and outdoor air with 1, 10 and 20 em-height of rainfall on the rooftop was $4.0^{\circ}C$, rooftop $1.2^{\circ}C$ and rooftop $1.0^{\circ}C$, respectively. The upper 10 em-height of rainfall on the rooftop acted to decrease the indoor air temperature on the top floor.

EFFECT OF DESIGN PARAMITERS ON SEASONAL PERFORMANCE OF AN A/C SYSTEM (공기조화기의 설계인자가 계절성능에 미치는 영향)

  • Park, Y.C.
    • 한국전산유체공학회:학술대회논문집
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    • 2010.05a
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    • pp.239-241
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    • 2010
  • Performance evaluation for an air conditioning system is conducted at a specified test conditions. One is low temperature and the other is high temperature condition. Most of the manufactures tried to improve the performance at higher outdoor temperature. One of the reasons is that the customer wants to get ore capacity at high temperature climate. To cope with these kinds of demand, manufactures are tried to achieve higher capacity at high temperature with minimum power consumption even with same size of the system. Consequently, previous studies on performance of the air conditioning system are focused on capacity and performance improvement at high outdoor temperature.

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An Experimental Study of Temperature Profiles in Mixing Zone of AHU with an Air Mixer (에어믹서가 설치된 공조기 혼합실 내의 온도분포에 관한 실험적 연구)

  • Pak, Kwon-Jong;Lee, Sek-Jun;Jang, Young-Keun
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.18 no.12
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    • pp.999-1006
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    • 2006
  • A study of temperature profiles in mixing zone of AHU (air handling unit) can contribute greatly to enhance performance of AHU system, so the study on the temperature distribution between RA (return air) and OA (outdoor air) is important to analyze the mixing characteristics in a mixing zone of AHU. Accordingly, the temperature profiles during RA (return air) and OA (outdoor air) supply process into mixing zone of AHU with an air mixer are studied experimentally. The effect of air mixer, OA temperature and RA/OA flow rate are studied in detail. In this study, the results show that the mixing efficiency is all high for installed the air mixer. The more OA temperature increase and OA flow rate decrease, the more mixing efficiency is high.

Outdoor $(1{\rightarrow}3)-{\beta}$-D-glucan Levels and Related Climatic Factors

  • Hwang, Sung Ho;Yoon, Chung Sik;Park, Jae Bum
    • Journal of Preventive Medicine and Public Health
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    • v.47 no.2
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    • pp.124-128
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    • 2014
  • Objectives: To evaluate the monthly variation in the airborne $(1{\rightarrow}3)-{\beta}$-D-glucan level throughout one year and its relationship with climatic factors (temperature, relative humidity, wind speed, hours of daylight, cloud cover, and pollen counts). Methods: A total of 106 samples were collected using a two-stage cyclone sampler at five outdoor sampling locations (on top of 5 university buildings). The kinetic limulus amebocyte lysate assay was used to obtain $(1{\rightarrow}3)-{\beta}$-D-glucan levels. Results: Airborne $(1{\rightarrow}3)-{\beta}$-D-glucan levels were significantly higher in the spring, particularly in April, and temperature was significantly related to $(1{\rightarrow}3)-{\beta}$-D-glucan levels (r=0.339, p<0.05). Conclusions: $(1{\rightarrow}3)-{\beta}$-D-glucan levels may be highest in the spring, and outdoor temperature may influence $(1{\rightarrow}3)-{\beta}$-D-glucan levels.

Thermal Performance of an Enthalpy Exchanger Made of Paper at Different Outdoor Temperatures and Humidities (외기 온·습도 변화에 따른 종이재질 전열교환 엘리먼트 성능에 관한 연구)

  • Kim, Nae-Hyun;Lee, Eul-Jong;Song, Kil-Sup;Oh, Wang-Kyu
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.7
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    • pp.697-702
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    • 2010
  • An enthalpy exchanger in which heat and moisture transfer occur between the indoor and outdoor air operates at various outdoor conditions. In this study, the effect of the outdoor-air temperature and humidity on the performance of an enthalpy exchanger was experimentally investigated. An apparatus was specially-made to accurately measure the incoming and outgoing dry- and wet-bulb air temperatures as well as the flow rates. Tests were conducted in constant-temperature and constant-humidity chambers at different outdoor temperatures and humidities. It is shown that the effectiveness of latent-heat exchange increases as the relative humidity increases; further, this effect exhibited minimal dependence on the absolute humidity. However, the effectiveness of sensible-heat exchange is independent of both temperature and humidity

Experimental Research Application to each Types of Insulation Materials in Rural Houses (농촌주택의 단열 재료별 현장 적용을 위한 실험 연구)

  • Kwon, Soon-Chan;Kim, Eun-Ja
    • Journal of the Korean Institute of Rural Architecture
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    • v.19 no.4
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    • pp.57-65
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    • 2017
  • Life quality in farming areas is declining these days on account of decrease in population with the outflow of young generations, advent of aging society, and also lack of social and physical infrastructure. To reverse this, the central and local governments have been devising policies in many ways; however, the vulnerable class in farming area suffering from financial difficulty is not supported with that properly. The results of applying insulation materials applicable to rural houses, EPS, e-board, and glass wool, actually to rural houses are summed as follows. EPS is the most inexpensive among the three installations in terms of material cost and expenses. The indoor and outdoor temperature difference increased from $0.9^{\circ}C$ to $2.5^{\circ}C$, and the temperature change reduced as $0.04^{\circ}C$. With e-board, the indoor and outdoor temperature difference increased from $3.3^{\circ}C$ to $7.5^{\circ}C$; however, the temperature change increased as $0.09^{\circ}C$. Unlike the other two methods, glass wool requires the additional installation of wooden frames. The material cost is highest, and the indoor and outdoor temperature difference increased from $1.1^{\circ}C$ to $8.0^{\circ}C$, and the temperature change reduced as $0.01^{\circ}C$. According to the results of measuring temperature, glass wool's temperature difference is measured to be the highest, but temperature change is found to be the most effective in EPS. Among the three insulation methods, EPS is the most economically advantageous as the material supply is easy and the cost is low. The material is easily processible, so ordinary town residents can install it easily, and it is effective at improving insulation performance, too. But this method cannot be applied when the house has walls that are not even. Also, as the insulator is thick, after the installation, the living space may be narrower as a result.

Application of Four-season Dedicated Outdoor Air Handling Unit in Central and Personal Air-conditioning (중앙공조 및 개별공조에서의 외조기 적용)

  • Park, Seung-Tae;Kim, Young-Il;Lee, Tae-Ho;Choi, Se-Young
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.591-596
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    • 2008
  • The present study has been conducted to study the performance of dedicated outdoor air handling unit in central and personal air-conditioning. With conventional central and personal air-conditioning systems which are designed according to the maximum load, humidity increase above comfort level can not be avoided as the cooling load decreases. The adoption of dedicated outdoor air handling unit, however, can solve this problem. Moreover, the dedicated outdoor air handling unit has the characteristics of anti-bacteria due to dry coil, energy saving and good indoor air quality. During cooling seasons, dedicated outdoor air handling unit can save energy up to 30% than the conventional cooling+reheating system for controlling both temperature and humidity.

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Analysis of Outdoor Design Temperatures for Heating and Cooling Greenhouses Based on Annual Percentiles (연간 백분위 방식에 의한 온실 냉난방 설계기온의 분석)

  • Nam, Sang-Woon;Shin, Hyun-Ho
    • Journal of Bio-Environment Control
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    • v.27 no.3
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    • pp.269-275
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    • 2018
  • In order to establish the criterion for analyzing outdoor weather conditions in the greenhouse heating and cooling system design, we analyzed heating and cooling design outdoor temperatures by the annual percentile method and compared with design outdoor temperatures by the existing seasonal percentile method. In the annual percentile method, 0.4%, 1% and 2% of the total 8,760 hours per year are presented as cooling design outdoor temperatures and 99.6% and 99% as heating design outdoor temperatures. When the annual percentile method was adopted, heating design outdoor temperatures increased by 6.7 to 9.6% compared with the seasonal percentile method, and cooling design outdoor temperatures decreased by 0.6 to 1.1%. The maximum heating load in the same greenhouse condition decreased by 3.0 to 3.6% when the annual percentile method was adopted, but the effect on the maximum cooling load was insignificant. Therefore, it is necessary to consider the change of heating design outdoor temperatures to the annual percentile method, but it is not necessary to change the cooling design outdoor temperatures since there is little difference between the two methods.

Outdoor Reset Control based on Fuzzy Algorithm for Radiant Floor Heating System (퍼지 알고리즘을 기반으로한 바닥복사 난방시스템의 외기보상제어)

  • Choi, Jong-Yo;Baek, Jae-Ho;Kim, Eun-Tai;Lee, Hee-Jin;Park, Mig-Non
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.1073-1074
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    • 2008
  • This paper presents outdoor reset control based on fuzzy algorithm for radiant floor heating system. We construct fuzzy system under indoor temperature and outdoor temperature. Simulation is based on TRNSYS with MATLAB. MATLAB is calculating and decide heat source using fuzzy system. Energy efficiency of Fuzzy algorithm is analyzed in term of indoor by TRNSYS System.

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