• Title/Summary/Keyword: Temperature change

Search Result 9,979, Processing Time 0.038 seconds

Women's Comfort Temperature Range and Dynamic Temperature Change for Maintaining Thermal Comfort in Low Temperature Environment (저온환경에서 여성 온열쾌적성 유지를 위한 쾌적온도범위 및 동적 온도변화 연구)

  • Kim, Soyoung;Lee, Okkyung;Lee, Heeran
    • Fashion & Textile Research Journal
    • /
    • v.22 no.6
    • /
    • pp.853-861
    • /
    • 2020
  • Various types of clothing are being developed to boost thermal comfort during cold winters along with research on change of body temperature when heating is applied. There is a noticeable behavioral difference by gender when using heating panels in a cold environment; however, research on women has been insufficient. This study find a temperature range that provides sustainable thermal comfort in a low temperature environment by observing temperature and change of temperature when subjects are classified according to physical activities or cold sensitivities. For the study results, 8 women in their 20s were subjected to experiment in a low temperature environment for 75 minutes (sitting position: 30 min., running: 15 min., and sitting position: 30 min.). Subjects were asked to turn on/off the heating panel freely to analyze the range of comfortable temperature and clothing microclimate; in addition, skin temperature and heating panel temperature were measured and analyzed at 9 points. As a result, temperature at which subjects turn on and off the heating panel indicated a statistically meaningful difference between the cold sensitivity group depending on exercise or non-exercise. The range of comfortable abdomen temperature was wider than the lower back and was significantly reduced when the subject was running. The range of comfortable temperature was also largest for the heating panel temperature, microclimate, and skin temperature in suggesting that adequate adjustment will be required depending on the surrounding environment or movement of the wearer.

Planning for Adapting to the Rural Region Impacts of Climate Change - Case study in Yesan - (기후변화에 따른 농촌지역 영향 및 대응방안 연구 - 예산군을 대상으로 -)

  • Lee, Gyeong-Jin;Cha, Jung-Woo
    • Journal of Korean Society of Rural Planning
    • /
    • v.19 no.4
    • /
    • pp.115-123
    • /
    • 2013
  • Owing to increase of meteorological disasters by climate change, it needs to study of climate change which will be able to deal with adaption for basic local authorities. A case study area of Yesan have been impacted by land-use which alter natural environment demage. It has led to micro-climate change impacts in rural area, Yesan. In order to adapt to the effects, this paper estimated temperature change in productivity of fruits and conducted decline of nonpoint pollutant loadings. As the results of temperature change of effecting on growth of apple, since a rise in temperature have not increased high, therefore the apple productivity could not be influence until 2030s. While the apple productivity could be declined 14.8% in 2060s. In addition, it supposes that the productivity would be decreased 44.5% in 2090s. Furthermore, it showed that the apple maturity has become worse, because length of high temperature has dramatic increased 54.2% in 2030s, 103.2% in 2060s and 154.0% in 2060s beside 2000, respectively, compared with 2000. As results of analysing between the future rainfall characteristics and nonpoint pollutant loadings, the subject of reduction of nonpoint pollutant was efficiency when it implemented around Oga-myeon or Deoksan-myeon Dun-ri. This study classified the region more detail each Eup and Myeon after that it analysed the rural region impacts of climate change for basic local authorities. Hence, this study is able to predict adaptation of rural region impacts of climate change. Due to increase of green house gases emission, meteorological disasters could often occur in the future. Therefore, it needs follow-up studies that assess climate change of effecting on rural region.

A Study on the SH Structure Change of Myosin Head by Temperature Effect (온도 영향에 따른 Myosin Head의 SH 구조 변화 연구)

  • 김덕술;송주영
    • Journal of Life Science
    • /
    • v.9 no.6
    • /
    • pp.646-652
    • /
    • 1999
  • The effect of temperature on the structure change of the SH of myosin head have been investigated with improved resolution by x-ray diffraction using synchrotron radiation. The movement of myosin head and conformational change of contractile molecules were occurred in the muscle contraction. IASL (iodo acetamide) and MSL (maleimide) disordered the orderly helix arrangement of myosin in the rest state of spin level. The temperature effect on the structure change was great at the UL in the equatorial reflection. But those of IASL and MSL were minor. Equatorial reflection (10, 11) change inferred that myosin head was moved to the vicinity of actin filament by temperature change (from $25^{\circ}C$ to $0^{\circ}C$) at UL, but spin level was not changed. The intensity change of 143 $\AA$ and 72 $\AA$ could offer information of the mass profection of population of myosin heads along the filament axis. The slope of intensity profile of the mass profection of 143$\AA$ and reflection of MSL is appeared sharply and those of UL and IASL were not changed. The decrease of MSL actin reflection at 51 $\AA$ and 59 $\AA$ in the actin reflection change refers that the shifted myosin head binds a certain actin or changes an actin structure. From these results, we could conclude that IASL and MSL were spin labeled on SH of myosin head and disordered the helix arrangement of actin.

  • PDF

Effects of Temperature Change on the Current Injected MRI (전류 주입 자기공명영상에 온도 변화가 미치는 영향)

  • 이수열;강현수;우응제;조민형
    • Journal of Biomedical Engineering Research
    • /
    • v.22 no.3
    • /
    • pp.303-309
    • /
    • 2001
  • It is well known that the electrical impedance of biological tissues is very sensitive to their temperature. In this paper, we have analyzed the effects of temperature change on the phase of magnetic resonance images obtained with external current injection. It has been found that the local phase in the current injected magnetic resonance image can be changed noticeably when local temperature change appears at a part of the tissue. At the experiments with a 0.3 Tesla MRI system, we observed the local phase changes at the phantom images when the phantom temperature was varied between 25 -45$^{\circ}C$. We think that the current injection MRI technique can be used for in-vivo monitoring of the temperature inside biiological tissues if the relation between the local temperature and phase can be quantified.

  • PDF

The Effects of the Annealing Temperature and Environments on Room Temperature Wear Behavior of Plasma-Sprayed Partially Stabilized Zirconia Coatings (플라즈마 용사된 부분안정화 지르코니아 코팅의 상온 마모거동에 미치는 열처리온도 및 분위기의 영향)

  • 김장엽;임대순
    • Journal of the Korean Ceramic Society
    • /
    • v.31 no.10
    • /
    • pp.1176-1180
    • /
    • 1994
  • The sliding wear behavior of the plasma-sprayed zirconia containing 3 mol% yttria was investigated after the annealing at room temperature to 80$0^{\circ}C$ in various concentrations of humid atmosphere as laboratory, humid, dry argon atmosphere. Both of the friction coefficient and the wear loss increased with increasing temperature up to 80$0^{\circ}C$. Surface morphology of the worn samples changed with annealing temperature. The change of monoclinic/tetragonal (m/t) x-ray peak intensity ratio effected the wear behavior. The m/t ratio had maximum value at 20$0^{\circ}C$ and decreased with increased temperature in laboratory and humid atmosphere. In argon atmosphere the m/t ratio had no maximum value and decreased with increasing temperature. At all the annealing temperature humid atmosphere had more the m/t ratio value than any other atmosphere. The change of toughness was showed the inversed result of m/t ratio change. The results indicated that the resudial stress which was induced by the different amount of phase transformation takes a detrimental role in wear behavior.

  • PDF

The finite difference analysis on temperature distribution by coordinate transformation during melting process of phase-change Material (상변화 물질의 용융과정에 있어서 좌표변환을 이용한 온도분포의 해석적 연구)

  • Kim, J.K.;Yim, J.S.
    • Solar Energy
    • /
    • v.5 no.2
    • /
    • pp.77-83
    • /
    • 1985
  • An analysis is performed to investigate the influence of the buoyancy force and the thickness variation of melting layer in the containment that is filled with phase-change Material surrounding a cylindrical heating tube during melting process. The phase-change material is assumed to be initially solid at its phase-change temperature and the remaining solid at any given time is still at the phase-change temperature and neglecting the effect of heat transfer occuring within the solid. At the start of melting process, the thickness of melting layer is assumed to be a stefan-problem and after the starting process, the change of temperature and velocity is calculated using a two dimensional finite difference method. The governing equations for velocity and temperature are solved by a finite difference method which used SIMPLE (Semi Implicit Method Pressure linked Equations) algorithm. Results are presented for a wide range of Granshof number and in accordance with the time increment and it is founded that two dimensional fluid flow occurred by natural convection decreases the velocity of melting process at the bottom of container. The larger the radius of heating tube, the higher heat transfer is occurred in the melting layer.

  • PDF

The Effects of an Additive on the Thermal Properties of a Clathrate Compound (III) - The Case of TMA Clathrate Compound with Acetone - (포접화합물의 열물성에 미치는 첨가제의 효과 (III) - TMA 물계 포접화합물에 Acetone을 첨가한 경우 -)

  • Kim Jin Heung;Chung Nak Kyu;Kim Suk Hyun;Kim Chang Oh;Kang Seung Hyeon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.16 no.12
    • /
    • pp.1183-1189
    • /
    • 2004
  • An experimental investigation is conducted to measure phase change temperature and supercooling when acetone is added to TMA 30 wt% clathrate during cooling process in heat source. Also rate of volume change is investigated when acetone is added to TMA 30 wt% clathrate during the cooling process in heat source -8$^{\circ}C$. The results show that phase change temperature is about 4.5~5.5$^{\circ}C$ when acetone is added to TMA 30 wt% clathrate during the cooling process for heat sink temperature of -6, -7$^{\circ}C$ and -8$^{\circ}C$. Supercooling is repressed about 2~1$0^{\circ}C$ when 0.08 wt% acetone is added to it and rate of volume change is decreased about 2.9% when 0.1 wt% acetone is added for the heat sink temperature of -8$^{\circ}C$.

Potential Influence of Climate Change on Shellfish Aquaculture System in the Temperate Region

  • Jo, Qtae;Hur, Young Baek;Cho, Kee Chae;Jeon, Chang Young;Lee, Deok Chan
    • The Korean Journal of Malacology
    • /
    • v.28 no.3
    • /
    • pp.277-291
    • /
    • 2012
  • Aquaculture is challenged by a number of constraints with future efforts towards sustainable production. Global climate change has a potential damage to the sustainability by changing environmental surroundings unfavorably. The damaging parameters identified are water temperature, sea level, surface physical energy, precipitation, solar radiation, ocean acidification, and so on. Of them, temperature, mostly temperature elevation, occupies significant concern among marine ecologists and aquaculturists. Ocean acidification particularly draws shellfish aquaculturists' attention as it alters the marine chemistry, shifting the equilibrium towards more dissolved CO2 and hydrogen ions ($H^+$) and thus influencing signaling pathways on shell formation, immune system, and other biological processes. Temperature elevation by climate change is of double-sidedness: it can be an opportunistic parameter besides being a generally known damaging parameter in aquaculture. It can provide better environments for faster and longer growth for aquaculture species. It is also somehow advantageous for alleviation of aquaculture expansion pressure in a given location by opening a gate for new species and aquaculture zone expansion northward in the northern hemisphere, otherwise unavailable due to temperature limit. But in the science of climate change, the ways of influence on aquaculture are complex and ambiguous, and hence are still hard to identify and quantify. At the same time considerable parts of our knowledge on climate change effects on aquaculture are from the estimates from data of fisheries and agriculture. The consequences may be different from what they really are, particularly in the temperature region. In reality, bivalves and tunicates hung or caged in the longline system are often exposed to temperatures higher than those they encounter in nature, locally driving the farmed shellfish into an upper tolerable temperature extreme. We review recent climate change and following environment changes which can be factors or potential factors affecting shellfish aquaculture production in the temperate region.

Heat Transfer in Heat Storage System with P.C.M. - Inward Melting in a Vertical Tube (상변화 물질을 사용한 축열조에서의 열전달 - 수직원관에서의 내향용융 실험 -)

  • Shon, H.S.;Hwang, T.I.;Lee, C.M.;Choi, G.G.;Yim, C.S.
    • Solar Energy
    • /
    • v.9 no.1
    • /
    • pp.53-61
    • /
    • 1989
  • In the present investigation, experiments on the melting of a phase change material were performed to research heat transfer phenomena generated by means of conduction and natural convection in the vertical tube at inward melting. The phase change material used in the experiments is 99 percent pure n-Docosane paraffin which is measured melting temperature of $42.5^{\circ}C$, latent heat of 37.5 cal/g, heat conductivity of $0.1505W/m^{\circ}C$. Experiments were performed both in the no-subcooling which is initiating it at melting temperature of phase change material, and in the subcooling which means to initiate it under melting temperature of phase change material, in order to compare and investigate the horizontal temperature history, vertical temperature history, ratio of melting and melted mass, figure of the melting front in the vertical tube. In the experimental results, heat transfer from tube wall to phase change material were due to conduction at early stage and due to natural convection with the passage of time, and then occurred melting downward from surface by volumetric expansion. Natural convection affects temperature distribution in the tube, ratio of melting and melted mass, figure of the melting front and then progress rapidly in case of nosubcooling compared to subcooling.

  • PDF

A Study on the Temperature Change of Green House using Aerogel (에어로젤을 사용한 시설하우스의 온도 변화에 대한 연구)

  • Yang, Ji-Ung;Lee, Eun-Suk;Ko, Joon-Young;Kim, Won-Kyung;Byun, Jae-Young;Park, Jin-Gyu;Choi, Won-Sik
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.23 no.6_2
    • /
    • pp.1067-1074
    • /
    • 2020
  • Green houses provide a more conditioned and warmer environment than the outside environment due to insulation. Currently used insulation materials include soft film (PVC, PE, EVA), foamed PE sheet, non-woven fabric, reflective film, and multi-layer insulation curtain, but there are many disadvantages and to compensate for this, silica aerogel insulation material with excellent warmth, light weight, and small volume Research using is in progress. In this study, the temperature change of the quadruple-structure green house and the temperature change in the dual-structure green house of soft film and silica airgel were investigated. The daytime temperature change was highest in A and A2 (soft film) at 10 to 16:00 after sunrise, but showed the lowest temperature at 17 to 18:00, which is the sunset time, showing the greatest change. The airgels of D and D2 showed the smallest change in temperature after sunrise and right after sunset. That is, it can be said that the airgel is hardly affected by external temperature. The temperature change at night was highest in D and D2 (aerogel) for both quadruple and dual structures. The temperature at night was measured higher in the quadruple structure than in the double structure. As for the ratio of the internal temperature to the external temperature for the quadruple structure and the double structure, D (aerogel) was not affected by the external temperature during the day in the quadruple structure and the double structure. D (Aerogel) seems to be able to reduce the damage caused by high temperatures in summer due to the high thermal insulation effect of the airgel, as the temperature rises above 4℃ at night. And in winter, it helps to save heating costs due to less heat emitted to the outside.