• 한국의류학회지
• /
• 제28권5호
• /
• pp.713-722
• /
• 2004

This study examined the effects of two kinds of functional sun hats through a head-manikin test and a climatic chamber trial for farm workers in summer. Experiment was composed of four conditions. The first condition was the condition without any hat (Control). The second was the condition with a sun hat on the market (Hat A). The third was the condition with a functional sun hat made of reflective fabric (Hat B). The last was the condition with a functional sun hat having a ventilating structure as well as reflective fabric (Hat C). For the subjects in the climatic chamber trials, 12 healthy males volunteered. Air temperature, relative humidity and globe temperature in the chamber was maintained at $33{\pm}0.5^{\circ}C,\;65{\pm}5%RH\;and\;39{\pm}1^{\circ}C\;(WBGT\;33^{\circ}C)$. Subjects did a simulated red pepper-work (50-min work and 10-min rest, twice repetition) for 120 min. As the result of head-manikin test, the surface temperature on middle of back-neck was the lowest in Hat B of four conditions and the surface temperature on top of head was the lowest in Hat C. As the result of climatic chamber trials, there were apparent differences between with (Hat A, Hat B, Hat C) and without a sun hat (Control). In rectal temperature ($T_{re}$), mean skin temperature ($\={T}_{sk}$), heart rate (HR), total sweat rate (TSR), The physiological heat strain was less in the condition with hats than in the condition without a sun hat. As the increasing rate in Tre, Hat B is the most effective hat for alleviation heat strain. As the subjective responses, Hat B was the most effective hat for thermal comfort even though the difference was not significant. Hat C was less effective than Hat B and the reason might be the increase of weight due to inserting the ventilating structure.

• Ecology and Resilient Infrastructure
• /
• 제4권4호
• /
• pp.187-192
• /
• 2017

본 연구는 보도, 차도, 주차장, 공원, 광장 등에서 많이 사용되고 있는 포장 재료인 블록의 증발 등 열적 성능을 평가하였다. 일반적으로 많이 사용되고 있는 일반블록과 LID (Low Impact Development)형 제품인 투수블록과 보수블록을 비교하였으며, 통제된 기후조건 (일사, 강우, 강설, 온도, 습도 등)이 갖춰진 챔버 (chamber) 내에서 실험을 수행하였다. 환경챔버 내의 공기온도와 상대습도가 제어되는 상태에서 강우설비와 로드셀을 활용하여 강우전과 후의 중량변화 및 일사장치와 송풍장치를 이용하여 증발량을 계측하였다. 결과적으로 보수블록이 일반블록에 비해 증발산량은 약 2.6배 많았으며, 표면온도는 $10^{\circ}C$, 공기온도는 $4.6^{\circ}C$ 낮았다. 따라서 블록시험에 강도, 투수성능뿐만이 아닌 열에 대한 부문도 추가하여 분석한다면, 도시의 열 환경개선에도 많은 도움이 될 수 있을 것이다.

• 한국의류학회지
• /
• 제28권8호
• /
• pp.1175-1185
• /
• 2004

This study evaluated thermo-physiological and subjective properties of improved disposable coveralls for railroad carriage maintenance through climatic chamber trials and a filed study. Subjects wore five kinds of disposable coveralls (Type A: a disposable coverall on the market, Type B: a coverall with an improved hood and size-adjustable design, Type C: a coverall with a portable hood, Type D: a coverall with small holes for ventilation, Type E: a sleeveless coverall, Type F: a separated type of coverall with half sleeves) The air temperature in the climatic chamber was set in 9$^{\circ}C$ and 30$^{\circ}C$ For each condition, subjects simulated the railroad work for 120min. and rectal temperature, skin temperatures, clothing microclimate and subjective sensations were measured. The results of chamber trials showed rectal temperature and clothing microclimate did not display significant differences by clothing type. In 30$^{\circ}C$ air temperature, mean skin temperature was higher in Type E and Type F than in Type A(p＜0.05) but between the improved coveralls(B-F), we could not find any significant difference. In the case of thermal comfort, the most preferred types were Type B and Type C in 9$^{\circ}C$ and Type F in 30$^{\circ}C$. All subjects felt more comfortable in the improved coveralls than in coveralls of the market (Type A). In field study, workers preferred Type B, Type C and Type F to Type A but the most favorite type differed by the specific type of work. Especially, workers were dissatisfied that Type D tore easily due to lots of small holes around the armpits and Type I did not protect workers＇ shoulder and arms from oil contamination. According to the climatic chamber trials and field study, the most effective coveralls were Type B and Type C for winter and Type F for summer.

• 한국농촌생활과학회지
• /
• 제5권2호
• /
• pp.107-115
• /
• 1994

This study was conducted to provide a counterplan for preventing so celled “plastic house syndrome” revealed among farmers spending much time in the plastic houses. For this, working environment inside a plastic house was observed. Then, experiments were carried out mostly in a climatic chamber with three kinds of working posture on uneven($D_1-F_1$) or even($D_2-F_2$) ground surface. Tested work loads with three kinds of working posture were : moving in a sitting posture with attaching breast to legs and waving arms ($A_1$), moving in a bending posture with waving arms ($B_1$), and moving a 6kg weighting luggage in a standing posture ($C_1$) Physiological responses in the workers to three different work loads were observed in a climatic chamber, with or without using some instruments, to evaluate work efficiencies. The results obtained are summerized as follows. 1. $C_1$ was the hardest work and $B_1$ was harder than $A_1$ on the even ground. 2. Worker's physiological fatigue and physical loads remarkably decreased when using the instruments such as a chair and a cart with some rollers on the even ground. 3. Working with pushing a cart($F_1$) was the hardest work, and standing($D_1$) was harder than walking($E_1$) on the uneven ground. 4. Worker's physiological fatigues and physical loads remarkably decreased on the even ground. 5. Similar results were obtained when the same experiment was carried out in a plastic house.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
• /
• pp.27-30
• /
• 2002

In this paper, we were investigated leakage current properties of outdoor insulator on climatic environmental factor. Contamination is one of the most important factor to determine the performance of insulator. Thus, it is very important to exam the contamination degree on the outdoor insulator. There are many limits, such as reliability of data, interval of measurement and similarity of environmental conditions, in conventional method. So, we measured phase and leakage current of outdoor insulator using the temperature & humidity chamber. In this investigation, phase difference was measured to compare the variance of phase difference with the contamination degree and relative humidity.

• 한국지역사회생활과학회지
• /
• 제22권3호
• /
• pp.445-454
• /
• 2011

This study was performed on 5 prehypertensive male participants to investigate the effects of the clothing program for improving the vascular compliance on heat tolerance. The clothing program means the alternate stimulation of the temperature using clothes. The participants wore two different garments with $1.5^{\circ}C$ difference in the temperature inside clothing in a climatic chamber ($18.8{\pm}0.2^{\circ}C$, $38{\pm}3%RH$) alternately for 4 weeks. Heat tolerance tests were conducted in the climatic chamber of $35.2{\pm}0.5^{\circ}C$, $54{\pm}3%RH$ before and after the clothing program. The results were as follows. The $\overline{T}$sk, Tr and heart rate were lower in the post test than in the pre test (p<.01). The whole body and local sweat rates as well as systolic and diastolic blood pressures had reduced the tendencies in the post test. Participants felt less wet and more comfortable in the post test than in the pre test(p<.01). These results showed that the clothing program through the alternate stimulation of the temperature positively affected the improvement of heat tolerance.

• 한국의류학회지
• /
• 제29권8호
• /
• pp.1176-1187
• /
• 2005

The purpose of this study was to evaluate the efficiency of cooling vests developed for farm workers harvesting red pepper in summer. The study was performed using the following two steps: 1) Climatic chamber test, 2) Field test. For the chamber test, a work environment was simulated as $33^{\circ}C$ and $65\%$RH, and the thermo-physiological and subjective responses were measured with and without cooling vests. Twelve young males participated as subjects. For the field test, three farmers participated while harvesting red pepper on the form, in summer. The measurements used were same as in the chamber test. Subjects were tested without any cooling vests, as a control. They were tested wearing vests with 2 frozen gel packs (CV2: Cooling area, $308cm^2$), and vests with 4 frozen gel packs (CV4: Sooting area, $616cm^2$). As a result of the chamber test, rectal temperature($T_{re}$) and mean skin temperature( $T_{sk}$) were lower in both CVs than in Control, and this tendency was statistically significant in CV4 (p<.05). Clothing microclimate temperature ($T_{clo}$) and total sweat rate (TSR) were significantly lower when wearing cooling vests (p<.05) Heart rate (HR) was also lower in wearing cooling vests than in Control, and the speed of recovery to the comfort level was faster when the subjects wore cooling vests. In addition, subjects felt 'less hot, less humid, and less uncomfortable' in both CVs than in Control. Field tests showed a similar tendency with the chamber tests. In particular, wearing the cooling vest was effective in restraining the raise of $T_{clo}$ on the back. It can be concluded that the cooling vest was effective in alleviating heat strain and discomfort in both the chamber test and the field test, despite the cooling area of the cooling vest being just $3.4\%$ of the body surface area ($616cm^2$).

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
• /
• pp.1327-1334
• /
• 2011

subway has became citizen's feet which can transport over 24 million people since the era of high oil price started. Because the request of passengers for more comfortable thermal comfort is drastically increasing, the importance of comfortable environment in the passenger car is more stressed. This paper suggests an indicator whether railroad car is fitted with suitable cooling and heating equipment by applying the international climatic testing method, UIC 553, 553-1. Specified ambient temperature, humidity, solar irradiation condition, as well as extreme outside condition, can be achieved by using an environmental chamber. The change temperature and humidity in the passenger space can be monitored to judge if the passenger room is nicely air-conditioned.

• 시스템엔지니어링학술지
• /
• 제6권1호
• /
• pp.41-46
• /
• 2010

The ground high/low temperature test objective is to check the normal ground operation of FA-50 aircraft in the extreme ground ambient conditions. The aircraft was exposed in climatic conditions of the basic climatic category according to the MIL-HDBK-310. For verified normal operation in the extreme high temperature, the high temperature test was performed in the hot regional type conditions and accentuated solar radiation heat. This test was performed at the test chamber in ADD where is in Haemi. This paper was described about the test procedure of FA-50 high/low temperature including preparation, testing and results.

• Mycobiology
• /
• 제35권4호
• /
• pp.191-195
• /
• 2007

The colonization pattern and extent of decay produced in paddy stubble by soil inhabiting mycoflora were done by using nylon net bag technique. Among the three methods used for isolation of fungi, dilution plate technique recorded the highest number of fungi followed by damp chamber and direct observation method. Nutrient availability and climatic conditions (temperature, humidity and rainfall) influenced the occurrence and colonization pattern of fungi. Maximum fungal population was recorded in October ($48.99{\times}10^4/g$ dry litter) and minimum in May ($11.41{\times}10^4/g$ dry litter). Distribution of Deuteromycetous fungi was more in comparison to Zygomycetes, oomycetes and ascomycetes. In the early stage of decomposition Mucor racemosus, Rhizopus nigricans, Chaetomium globosum and Gliocladium species were found primarly whereas at later stages of decomposition preponderance of Aspergillus candidus, Torula graminis, Cladosporiun cladosporioides and Aspergillus luchuensis was recorded.