• 제목/요약/키워드: elevated temperature and humidity

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소방공무원의 방화복 착용 후 단계별 운동강도 변화 시 의복 내 온도·습도·발한량 차이 (The change in temperature·humidity·perspiration of fire suit when applying phased intensive exercises to fire fighter wearing fire suit)

  • 최서연;박일규;공일천;이동호
    • 대한안전경영과학회지
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    • 제15권4호
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    • pp.97-103
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    • 2013
  • The purpose of this study was to verify the change in temperature humidity perspiration of fire suit when applying phased intensive exercises to fire fighter wearing fire suit. For this study, three male fire fighters took basic physical test and performed 10 minute phased intensive exercises -exercise intensity I (30%VO2max), exercise intensity II (45%VO2max), exercise intensity III (60%VO2max) based on maximum oxygen consumption (VO2max)- wearing fire suit (helmet, boots, air respirator) in treadmill and took a rest. The result of study shows that the temperature in the suit elevated during stabilization period after each exercise intensity, humidity elevated as exercise intensity increased, perspiration elevated as exercise intensity increased. This study indirectly ascertained the fire suit's physiological change in fire fighters during field activities.

황색종 연초 건조중 황변기 온습도차가 잎담배 색상 및 화학성분에 미치는 영향 (EFFECT OF TEMPERATURE AND HUMIDITY ON THE LEAF COLOR AND CHEMICAL COMPONENTS DURING THE YELLOWING STAGE OF FLUE-CURING)

  • 황건중;석영선;이한석
    • 한국연초학회지
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    • 제7권2호
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    • pp.129-139
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    • 1985
  • cent was carried out to study on the effect of temperature and humidity to chemical tobacco leaves during the yellowing stage. The results were follows : In the condition of high humidity and low temperature, yellowing time was delayed ; leaf color appeared lack clearness. In the higher temperature and the lower humidity during the yellowing stage : total sugar, reducing sugar and malic acid content were increased. Decomposition of nitrogenous components elevated in $38^{\circ}C$, 85%RH. Changes of total nitrogen content correlated with total curing time. Adecrease of linolenic acid with a corresponding increase of chlorogenic acid proceeded in the condition of low temperature and high humidity. In a view of tobacco quality by chemical components, the low temperature and high humidity during the yellowing stage decreased quality of tobacco leaves. It is considered to control of the proper condition of temperature and humidity during the yellowing.

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산화 알루미늄 및 냉각거울 노점계의 온도 의존성에 관한 연구 (The Effect of Temperature on Aluminum Oxide and Chilled Mirror Dew-point Hygrometers)

  • 김종철;최병일;우상봉;김용규;이상욱
    • 센서학회지
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    • 제26권1호
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    • pp.50-55
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    • 2017
  • The measurement of absolute humidity of gases is essential in many industries. The effect of temperature on aluminum oxide and chilled mirror dew-point hygrometers is investigated. The temperature of laboratory, pipe line, and sensor is varied and the dew point is measured by two different aluminum oxide hygrometers. In all cases, the dew point of hygrometers is increased as the temperature is elevated. The reason behind this observation is due to desorption of water from the inside of pipe line and/or sensor surroundings at elevated temperature that result in the increase of the absolute humidity. Moreover, the sensor itself shows a certain degree of temperature dependency in sensing the humidity especially at low temperature. It is also studied that chilled mirror dew-point hygrometer may indicate a higher dew point than the reference at high temperature because the cooling capability of mirror is decreased at high temperature. Our study will provide evidences in the incorporation of the temperature effect as uncertainty factors in the standard calibration procedure for dew point hygrometers.

간헐공조 전시관내 유물 진열장의 온·습도 환경 분석 (Analysis for Temperature and Relative Humidity of Showcase in Exhibition Hall Operated Intermittent Air Conditioning)

  • 이선명;임보아;김서진
    • 보존과학회지
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    • 제29권4호
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    • pp.311-320
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    • 2013
  • 조사 대상인 유물 진열장은 온도 변화에 대응한 조온기능이 미약한 반면 조습 능력이 비교적 높았다. 유물 진열장 내부의 연평균 온 습도는 $18.8^{\circ}C$, 60.3% 로 전시실에 비해 온도는 낮고 습도는 높은 분포를 나타냈다. 또한 온도는 계절변화에 따라 변동률이 높은 반면 습도는 계절별 평균값이 59~61%로 일정하게 유지되었다. 여름철에는 전시실과 마찬가지로 고온고습 분포를 나타냈고 공조기 가동에 따른 온도의 하강은 습도를 상승시켰으며. 겨울철에는 공조기 가동에 따라 전시실과 유물 진열장 간 온 습도의 차이가 커져 수분 문제가 제기되었다. 유물 진열장 내부 온 습도에 대한 PI는 18.0%로 전시물 보존을 위한 적정 온 습도 조성률이 매우 저조하였다. 특히 여름철과 겨울철은 PI가 1% 미만으로 진열장 내 철저한 온습도 관리가 필요할 것으로 판단된다.

Analytical model for CFRP strengthened circular RC column under elevated temperature

  • Rashid, Raizal S.M.;Aboutaha, Riyad S.
    • Computers and Concrete
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    • 제13권4호
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    • pp.517-529
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    • 2014
  • In order to increase the load carrying capacity and/or increase the service life of existing circular reinforced concrete bridge columns, Carbon Fiber Reinforced Polymer (CFRP) composites could be utilized. Transverse wrapping of circular concrete columns with CFRP sheets increases its axial and shear strengths. In addition, it provides good confinement to the concrete column core, which enhances the bending and compressive strength, as well as, ductility. Several experimental and analytical studies have been conducted on CFRP strengthened concrete cylinders/columns. However, there seem to be lack of thorough investigation of the effect of elevated temperatures on the response of CFRP strengthened circular concrete columns. A concrete confinement model that reflects the effects of elevated temperature on the mechanical properties of CFRP composites, and the efficiency of CFRP in strengthened concrete columns is presented. Tensile strength and modulus of CFRP under hot conditions and their effects on the concrete confinement are the primary parameters that were investigated. A modified concrete confinement model is developed and presented.

The Wearing Sense of Male Adult Shoes - Comparison of Common Shoes with Elevated Shoes -

  • Shim, Boo-Ja;Yoo, Hyun
    • 패션비즈니스
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    • 제11권6호
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    • pp.35-51
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    • 2007
  • This research was administered in order to know the effects of heels on the foot by comparing the foot environmental characteristics when common shoes and elevated shoes are worn. First, 157 male adults in their 20s through 40s living in Busan were the inquiry subjects to reveal the shoes-wearing reality of adult males. Second, 7 male adults in their early 20s became the subjects for the experiments of wearing common shoes and elevated shoes. 1. Inquiry Results of Shoes-Wearing Reality Common-shoes wearers were in the order: 20s (43.9%) > 30s (24.8%) > 40s (8.3%). Elevated-shoes wearers were mostly 20s (12.1%), followed by 30s (8.3%) and 40s (2.5%). Among the wearing effects of elevated shoes were 'looking taller' (66.7%), 'no height complex & more confidence' (30.6%), and 'higher work efficiency' (2.8%). In sum, 97.3% of the male subjects believed in great positive effects by wearing elevated shoes. 2. Shoes-Wearing Experiment Results In foot skin temperature, significant differences between the two groups were admitted in outer foot a (p<0.05) and other areas (p<0.001), except in the instep. Elevated-shoes group had bigger skin temperature, while the order of temperature was the instep, the big toe, inner foot a/b/c and outer foot a/b/c. Significant difference was accepted in total sweat rate (p<0.05) and local sweat rate (p<0.01). Elevated-shoes group appeared higher in both rates. Significant difference (p<0.001) between the two groups was recognized in fatigue degrees after wearing, whereas significance (p<0.05) in elevated-shoes group was approved in fatigue before and after exercise. So elevated-shoes group experienced more fatigue, especially after exercise.

환경변화에 따른 VCR 코팅드럼의 가속실험 (Accelerated Testing of Coated VCR Drum Under Various Environmental Conditions)

  • 박우현;황동환;김대은;이상조;유대은;김금모;최계철
    • 대한기계학회논문집A
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    • 제20권10호
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    • pp.3095-3104
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    • 1996
  • The tribological characteristics of TIN and DLC coated VCR drums were compared to conventional aluminum drums using a custom built accelerated testing set-up under varying temperature and humidity. It is found that the coated drums exhibit superior frictional properties at elevated temperature and high humidity compared to bare aluminum drum. Futhermore, the coated drums maintained their initial surface conditions over a wider range of temperature and humidity variation. As for the damage incurred to the tape, DLC coated drum was the most favorable of the three types of drums.

A Study on the Plasma Biochemical Indices of Heat-Stressed Broilers

  • Lin, H.;Du, R.;Gu, X.H.;Li, F.C.;Zhang, Z.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권9호
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    • pp.1210-1218
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    • 2000
  • Four experiments were conducted to evaluate the effect of temperature and humidity on biochemical indices of Arbor Acres broilers at different weeks of age. The alkaline phosphatase (AKP), acid phosphatase (ACP), lactic dehydrogenase (LD), creatine kinase (CK), plasma glucose (Glu), calcium (Ca), potassium (K), chloride (Cl), urea nitrogen (UN), uric acid (UA), plasma thyroxin (T4), triiodothyronine (T3) and insulin levels were determined in all the four experiments. In experiment 1, the plasma Glu, LD and CK levels were increased by heat exposure ($35{^{\circ}C}$ and 35, 60, or 85% RH, 2 h) and this effect was aggravated by longer exposure (24 h). No significant changes (p>0.05) were found in Ca concentration, activity of AKP and ACP. In experiment 2, temperature (10, 20, 30, $33{^{\circ}C}$) had significant effect on the levels of K, Cl, UN, UA levels and the activity of LD (p<0.01), but had no significant influence on the activity of CK (p>0.05). The UN, UK and LD levels were elevated by low temperature $(10{^{\circ}C})$ (p<0.01), Cl content was increased by high temperature ($(33{^{\circ}C})$ (p<0.01), and K level was decreased by high ($(33{^{\circ}C})$ or low $(10{^{\circ}C})$ temperature and increased by medium temperature $(30{^{\circ}C})$ (p<0.01). The humidity (35, 85% RH) only had significant effect on Cl concentration which was decreased by high humidity (p<0.01). In experiment 3, the result showed that only the LD and CK activity were significantly increased (p<0.01) by high temperature (7, 24, 28, $32{^{\circ}C}$) or high humidity (35, 85% RH). Temperature and humidity had no significant effect on K, Cl, UA, UN and Glu levels (p>0.05). In experiment 4 (24, 27, 30, $33{^{\circ}C}$; 30, 45, 60, 75, 90% RH), plasma T3 level was declined by high temperature $(33{^{\circ}C})$, and this phenomena disappeared in birds under high temperature and high humidity environment. T4 concentration in plasma was not affected by temperature (p>0.05), but was increased by high or low humidity (p<0.01). Neither temperature nor humidity had significant effect on plasma insulin concentration (p>0.05). The results of the four experiments suggested that broilers at different growth periods might have different thermal requirements and would response differently to heat exposure. The plasma biochemical indices themselves had big variation; the reaction of the indices to thermal exposure treatment differed with the age of broilers. The big variation of biochemical indices themselves might cover the response of indices to temperature and humidity treatments.

Artocarpus chaplasha: Establishment and Initial Growth Performance at Elevated Temperature and Saline Stresses

  • Rahman, Md. Siddiqur;Al-Amin, M.;Akter, Salena
    • Journal of Forest and Environmental Science
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    • 제28권1호
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    • pp.12-18
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    • 2012
  • Like any other natural resources, forest flora may experience the extreme threat of elevated temperature and saline water submergence at different stages of their lives i.e. from germination to maturity due to climate change effects. The overall aim of the study was to measure the effect of higher temperatures along with saline water irrigation on survival and initial growth during seedling stage of Artocarpus chapalasha. The experiment was conducted in temperature- humidity-photoperiod regulated plant growth chamber during stipulated period to measure the growth performance of randomly selected seedlings. Within three different elevated temperatures viz. $30^{\circ}C$, $32^{\circ}C$ and $34^{\circ}C$, the seedlings were given three different saline conditions such as 0.5 g/L, 1.5 g/L and 2.5 g/L NaCl concentrations. Results found from the experiment was that, seedlings of Artocarpus chaplasha reared at different temperatures and saline water treatments showed stunted growth than reared at existing outdoor temperature ($26.31^{\circ}C$) irrigated with regular fresh water. Seedling growth at three different parameters such as height, collar diameter and number of leaves showed that with increasing temperature individuals respond negatively to increasing saline condition. The seedling's growth occurred at every day in height, collar diameter and leaf. However, growth rate reduced later during the observation. The combined effect of high salinity and higher elevated temperature results in seedling mortality. Therefore, Artocarpus chaplasha may not thrive at higher temperature and salinity intrusion at its early growing period in plantation and natural forest areas.

Effects of Relative Humidity and Temperature on the Transport of Chloride in the Concrete

  • Nam Jin-Gak;Hartt William H.;Kim Ki-Joon
    • 콘크리트학회논문집
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    • 제17권5호
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    • pp.821-828
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    • 2005
  • To investigate the role of RH and temperature on the transport of chloride in the concrete, two groups of specimens were configured. For both groups, mix design was based on w/c=0.45, $400kg/m^3$ cement, $794kg/m^3$ fine aggregate and $858kg/m^3$ coarse aggregate. After specimen fabrication these were exposed to four different RH (35, 55, 75 and $95\%$ RH) and temperature (0, 20, 30 and $40^{\circ}C$) conditions. After 3 and 6 months $15\%$ NaCl exposure 5mm cores were taken. These cores were sliced and individual cores were ground to powder. In addition, to evaluate the effect of temperature on the chloride binding some powder samples were leached in the each of four temperature chambers. Chloride titration fur these was performed using FDOT acid titration method. Based upon the resultant data conclusions were reached regarding that 1) effective diffusion coefficient, $D_e$, increased with increasing exposure RH, suggesting that the size and number of water paths increased with elevated moisture content in the specimens, 2) $D_e$ increased with increasing temperature in the range of 0 to $40^{\circ}C$ possibly by elevated thermal activation of chloride ions and reduced chloride binding at higher temperature, 3) water soluble chloride concentration, $[Cl^-]_s$, increased with increasing temperature, and 4) chloride concentration profile for initially dry concrete specimens was higher than for the initially wet ones indicating pronounced capillary suction (sorption) occurred for the dry concrete specimens.