• 제목/요약/키워드: local skin temperature

검색결과 88건 처리시간 0.022초

Effect of a chemical reaction on magnetohydrodynamic (MHD) stagnation point flow of Walters-B nanofluid with newtonian heat and mass conditions

  • Qayyum, Sajid;Hayat, Tasawar;Shehzad, Sabir A.;Alsaedi, Ahmed
    • Nuclear Engineering and Technology
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    • 제49권8호
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    • pp.1636-1644
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    • 2017
  • The main purpose of this article is to describe the magnetohydrodynamic stagnation point flow of Walter-B nanofluid over a stretching sheet. The phenomena of heat and mass transfer are based on the involvement of thermal radiation and chemical reaction. Characteristics of Newtonian heating are given special attention. The Brownian motion and thermophoresis models are introduced in the temperature and concentration expressions. Appropriate variables are implemented for the transformation of partial differential frameworks into sets of ordinary differential equations. Plots for velocity, temperature, and nanoparticle concentration are displayed and analyzed for governing parameters. The skin friction coefficient and local Nusselt and Sherwood numbers are studied using numerical values. The temperature and heat transfer rate are enhanced within the frame of the thermal conjugate parameter.

EFFECTS OF SORET AND DUFOUR ON NATURAL CONVECTIVE FLUID FLOW PAST A VERTICAL PLATE EMBEDDED IN POROUS MEDIUM IN PRESENCE OF THERMAL RADIATION VIA FEM

  • RAJU, R. SRINIVASA
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제20권4호
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    • pp.309-332
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    • 2016
  • Finite element method has been applied to solve the fundamental governing equations of natural convective, electrically conducting, incompressible fluid flow past an infinite vertical plate surrounded by porous medium in presence of thermal radiation, viscous dissipation, Soret and Dufour effects. In this research work, the results of coupled partial differential equations are found numerically by applying finite element technique. The sway of significant parameters such as Soret number, Dufour number, Grashof number for heat and mass transfer, Magnetic field parameter, Thermal radiation parameter, Permeability parameter on velocity, temperature and concentration evaluations in the boundary layer region are examined in detail and the results are shown in graphically. Furthermore, the effect of these parameters on local skin friction coefficient, local Nusselt number and Sherwood numbers is also investigated. A very good agreement is noticed between the present results and previous published works in some limiting cases.

한랭환경하에서 인체의 국소가온 자극이 온열생리.감각반응에 미치는 영향 (Physiological and Psychological Thermal Responses to Local Heating of the Human Body in a Cold Environment)

  • Shin, Jounghwa
    • 한국의류학회지
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    • 제25권10호
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    • pp.1745-1753
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    • 2001
  • 본 연구는 한랭 환경 하에서의 인체의 국소 가온 자극이 생리, 감각반응에 끼치는 영향을 검토했다. 건강한 성인여자 7명을 대상으로, 기온 $25^{\circ}C$, 습도50%의 환경 하에서 균일한 국소 가온을 부하 했을 때 피부온, 고막온, 손가락, 발가락 혈류량, 온냉감, 쾌적감의 반응에 미치는 영향을 검토한 결과는 다음과 같다. 1) 국소가온에 의해 가온 부위 피부온은 유의하게 상승하고 가온 부위에 따라 상승도에는 유의한 차가 보였다. 2) 국소가온에 의해 고막온은 머리의 가온 시에 높은 상승, 전완의 가온 시에 상승하고, 다른 가온 부위에서는 하강의 경향이 보였다. 3) 국소가온에 의해 혈류량의 변화는 3개의 군으로 분류된다. 가온과 함께 손가락 혈류량이 증가하는 군, 발가락 혈류량이 변화하는 군, 양쪽의 혈류량이 적게 변화하는 군으로 나누어진다. 이것을 각 피험자의 평균 피부온 수준 즉 체온조절 수준과 관계 있는 것으로 논할 수 있다 4)국소 가온에 의해 각 부 위 피부온으로의 파급효과는 머리, 상완의 가온 시에 크지만 대퇴, 하퇴 다리의 가온 시에는 대부분의 부위에서 영향이 보이지는 않았다. 5) 이와 같이 국소 가온에 의 한 생리, 감각반응은 가온 부위에 따라 다르고 머리, 상완의 가온 시에는 생리반응이 크고 하퇴, 다리의 가온시에는 국소의 감각변화가 컸다.

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운동복의 기능성과 쾌적성에 관한 연구 (Sportswear Physiological Optimization: Effects of Clothing ease, local heating and materiales)

  • 이영숙;안태환
    • 한국의류학회지
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    • 제15권2호
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    • pp.127-138
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    • 1991
  • The aim of the present stud)r has been to obtain new and additional data allolwing a better design of sports garments as well as a better choice among some materiales, through measure-ment of body surface changes in the upper trunk in movement, measurement on the effects of local heating on other parts of the body and measurement of the thermal resistance of 6 types of materials applied on a manikin. In the first experiment, the upper trunk was divided in 32 Parts, the surface of which was measured by the tape method for two upper limb positions: extension at $90^{\circ}$ and $180^{\circ}$. In the second experiment, skin temperature, local thermal sensations and whole body thermal sensation were measured every 5 minutes during 40 minutes. The four areas of the shoulder, abdomen, hande and feet were heated with the hot pack at $50^{\circ}C$. In the third experiment, the regional thermal resistance of the various materials selected, in two different cases of clothing ease, have been measured by using a thermal manikin. Resultes of experiments were: 1. Extensions cause the upper front part of the trunk surface to lengthen vertically while the back tends to stretch in width. 2. Skin temperatures of the upper limbs are influenced by the abdomen and shoulder boatings. The correlation between the whole body thermal sensation and the upper trunk thermal sensation is significantly asserted. 3. Ceramic and aluminium coated materiales offer the most effective thermal resistance; ease in clothing increases the thermal resistance at the breast and the abdomen as well as the clo value of the materials.

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성인 남녀의 투습방수소재 스포츠 웨어의 소재별 착용감에 관한 연구 (The Wearing Sensation of Men and Women in Sports Wear with Waterproof and Water Vapor Permeable Fabrics)

  • 조지현;류덕환
    • 한국생활과학회지
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    • 제9권1호
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    • pp.47-61
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    • 2000
  • The purpose of this study was to examine the performance and properties of sports wear that have the excellent wearing sensation and are in harmony with the functions of human bodies. With four kind(sample A, B, C, D) of materials which have different water vapor transmission, the physiological responses of human bodies and the changes of subjective sensations were studied through the actual aerobic sports program at $20^{\circ}C$, 60%R.H. The forehead temperature had the minimal variation among the local skin temperatures. The fabrics of low water vapor transmission demonstrated high breast temperature. There are significant differences among materials depending on the humidity in clothes(especially back and breast), which was about 6 % for breast and about 14 % for back. The order of loss in body weight was in the opposite direction to that of water vapor transmission for each material.

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The Effects of Skin Pigmentation on Physiological Factors of Thermoregulation and Grazing Behaviour of Dairy Goats in a Hot and Humid Climate

  • Darcan, Nazan Koluman;Cankaya, Soner;Karakok, Serap Goncu
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권5호
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    • pp.727-731
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    • 2009
  • The aim of this study was to understand the effects of skin pigmentation on physiological parameters of thermoregulation and grazing behaviour of dairy goats in a hot and humid climate. The study used 26 crossbred Saanen yearling goats (95% Saanen+5% Local Hair Breed). The animals were raised at semi-intensive private farms in Adana (36 59'N, 35 18'E). Groups were selected 2 d before the start of observations. Goats were categorized as predominantly pigmented (P) skin and unpigmented (UP) skin. All observations and measurements were collected on grassland during the grazing period of June and July 2007 (60 d). Air temperature and relative humidity were recorded at 10 min intervals by a portable data logger. The physiological data (rectal temperature, respiration and pulse rate, and skin temperatures from head and udder) were recorded twice weekly in the morning (07:00-08:00); at midday (13:00-14:00); and in the evening (18:00-19:00). Additionally, the activity of the animals was observed and classified (eating, ruminating, drinking, standing, walking, lying) for 12 h during the day twice weekly, using a portable camera system linked directly to a computer. Panting behaviour was also observed. According to the THI values, the experimental goats were subjected to stressful conditions. The pigmented goats had significantly lower rectal temperatures (39.68 vs. $29.89^{\circ}C$), pulse rate (74.08 vs. 84.10 beat/min) and respiration rate (65.65 vs. 88.23 breath/min.) compared with unpigmented goats at midday when the THI exceeded 92. The rectal, head and udder temperatures, pulse and respiration rates of the non-pigmented group exceeded $40^{\circ}C$, $37^{\circ}C$, $37.5^{\circ}C$, 84 beats/min and 78 breaths/min, respectively. Higher activity was observed among pigmented compared with unpigmented goats. Unpigmented goats grazed (4.3 vs. 5.6 h), ruminated (2.0 vs. 2.4 h), and stood (0.8 vs. 1.2 h) less, but lay down (2.2 vs. 1.8 h) more than pigmented goats. The data obtained in this experiment support the hypothesis that unpigmented goats are more adversely affected by climatic stress, likely due to their decreased activity and increased water consumption, as demonstrated by previous studies.

여름철 냉방 조건에서의 착의 훈련이 인체의 체온 조절 반응에 미치는 효과 (Effect on the Human Thermoregulation of Wear Training in Air Condition)

  • 김미경;최정화;염희경
    • 한국의류학회지
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    • 제19권3호
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    • pp.504-515
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    • 1995
  • This study was performed to investigate that wear training using thermal insulation with clothes has the effect on the human thermoregulatory response, especially on the heat tolerance. Twelve men and women in twenties wert divided into the control group, the training groups and each group except the control group had participated in wear training. The heat tolerance was assessed in all subjects who had participated in the experiment carried out in hot environment(40$\pm$1$^{\circ}C$, 50$\pm$5%RH) by such parameters as rectal temperature, skin temperature, systolic blood pressure, diastolic blond pressure, plume rate, total sweat volume, local sweat volume, subjective sensation, and the differences of heat tolerance in each group were compared. The results were as follows: In hot environment(4$0^{\circ}C$) the changing width of rectal temperature was decreased in the control and the heavy clothing group. Forehead and abdomen temperature in hot environment were significantly decreased after the training. Sweat rate was higher after the training than before. In all experimental groups, systolic and diastolic blood pries.;uses in hot environment(4$0^{\circ}C$) were significantly decreased after the training.

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다한증 환자에서 흉부 교감신경절 차단과 인지 체온 변화와의 관계 (Changes of Index Finger Temperature as Indices of Success of Thoracic Sympathetic Ganglion Block)

  • 이효근;윤경봉;서영선;김찬
    • The Korean Journal of Pain
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    • 제7권2호
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    • pp.217-221
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    • 1994
  • Percutaneous neurolysis of upper thoracic sympathetic ganglion was performed in 40 patients by simultaneously injecting 3 ml of pure alcohol into the T2 and T3 levels after 3 ml of injection of local anesthetic agent on the same sites. Using a skin temperature probe, finger tip temperatures were measured on the index finger ipsilateral to the nerve block before block, 15 and 30 minutes after test block, and 30 minutes after alcohol block. Alcohol block was performed immediately after 30 minutes test block. Finger tip temperatures obtained at 30 minutes post alcohol block and test block and the differences in the temperatures measured before and 30 minutes after alcohol block were shown to be statistically important as potential indicators for prediciting long term outcome of therapy for palmar hyperhidrosis using this technique. These results demonstrate that the palmar temperature monitoring method is sufficiently sensitive to predict the outcome of nerve block during and after thoracic sympathetic ganglion block.

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In vivo verification of regional hyperthermia in the liver

  • Noh, Jae Myoung;Kim, Hye Young;Park, Hee Chul;Lee, So Hyang;Kim, Young-Sun;Hong, Saet-Byul;Park, Ji Hyun;Jung, Sang Hoon;Han, Youngyih
    • Radiation Oncology Journal
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    • 제32권4호
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    • pp.256-261
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    • 2014
  • Purpose: We performed invasive thermometry to verify the elevation of local temperature in the liver during hyperthermia. Materials and Methods: Three 40-kg pigs were used for the experiments. Under general anesthesia with ultrasonography guidance, two glass fiber-optic sensors were placed in the liver, and one was placed in the peritoneal cavity in front of the liver. Another sensor was placed on the skin surface to assess superficial cooling. Six sessions of hyperthermia were delivered using the Celsius TCS electro-hyperthermia system. The energy delivered was increased from 240 kJ to 507 kJ during the 60-minute sessions. The inter-session cooling periods were at least 30 minutes. The temperature was recorded every 5 minutes by the four sensors during hyperthermia, and the increased temperatures recorded during the consecutive sessions were analyzed. Results: As the animals were anesthetized, the baseline temperature at the start of each session decreased by $1.3^{\circ}C$ to $2.8^{\circ}C$ (median, $2.1^{\circ}C$). The mean increases in temperature measured by the intrahepatic sensors were $2.42^{\circ}C$ (95% confidence interval [CI], 1.70-3.13) and $2.67^{\circ}C$ (95% CI, 2.05-3.28) during the fifth and sixth sessions, respectively. The corresponding values for the intraperitoneal sensor were $2.10^{\circ}C$ (95% CI, 0.71-3.49) and $2.87^{\circ}C$ (1.13-4.43), respectively. Conversely, the skin temperature was not increased but rather decreased according to application of the cooling system. Conclusion: We observed mean $2.67^{\circ}C$ and $2.87^{\circ}C$ increases in temperature at the liver and peritoneal cavity, respectively, during hyperthermia. In vivo real-time thermometry is useful for directly measuring internal temperature during hyperthermia.

Implantable Port System을 이용한 복합부위통증증후군 치험 1예 -증례 보고- (A Case of CRPS Treated with Implantable Port System -A case report-)

  • 신성식;김태삼;양인숙
    • The Korean Journal of Pain
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    • 제10권2호
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    • pp.274-277
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    • 1997
  • The complex regional pain syndrome(CRPS) exhibit symptoms such as: abnormal skin color, temperature change, abnormal pseudomotor activity, edema. If CRPS is not treated appropriately at acute stage, then the affected extremity may become a useless, painful appendage. Treatment of CRPS by sympathetic blockade may be achieved by repeated intravenous regional guanethidine blocks, repeated anesthetic sympathetic blocks, surgical sympathectomy or oral sympatholytic therapy. We treated 29-year-old male patient with CRPS of left upper extremity by continuous cervical epidural blockade. Due to wound infection and dislocation of the epidural catheter, we inserted an implantable port system to inject the mixture of local anesthetics and small amount of morphine. After 10 months of treatment, patient was cured of symptoms and signs of CRPS and was able to resume a normal life.

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