• 한국축산시설환경학회지
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• 제1권1호
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• pp.39-45
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• 1995

Temperatures of blood and skin, respiratory rate and plasma cortisol concentration in sheep at a warm (average ambient temperature of $15.3^{\circ}C$) and a hot (average ambient temperature of $27.0^{\circ}C$ environment were measured to investigate the effect of hot environment on the physiological responses in ruminant. Temperatures of core, mean skin and mean body in sheep were tended to increase at day time and to decrease at night time at both warm and hot environment, while 24-hr average for those temperatures were significantly higher at hot environment than at warm environment (P<0.05). The calculated body heat content was higher in sheep at hot environment than at warm environment (P<0.05). Respiratory rate and plasma cortisol concentration had no significant differences between warm and hot environment, suggesting that sheep were not stress by the hot environment in this experiment. It is, therefore, suggested that sheep were well adopted to hot environment by increasing body heat content against heat stress.

• 대한한방소아과학회지
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• 제29권2호
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• pp.1-15
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• 2015

Objectives In the theory of Korean Medicine, Cicadae Periostracum (CP) has been used to treat skin diseases such as inflammatory dermatitis, tetanus and pruritus. CP can reduce heat and disperse wind. In prior studies, anti-allergic effect and anti-inflammatory effect of CP were reported. However, there has been no report regarding the correlation of CP and allergic contact dermatitis (ACD). This study was performed to show the effects of CP in ACD induced by 2,4-dinitrochlorobenzene (DNCB) in mice. Methods In this experiment, the effects of CP on biological changes were measured, such as changes in ear and spleen weight, ear and dorsum skin thickness, clinical aspect on the dorsum skin and histological changes. The effect of proliferation rate of splenocytes was also investigated in vitro and vivo study. Results In results, CP application (CPA) group and CP application and administration (CPAA) group were significantly restrained in ear weight gain and increase in ear and dorsum skin thickness compared to the control group. In addition, CPA and CPAA group showed diminished erythema, desquamation, bloodstain, and marks. Also, the histological assessment showed that CP treatement diminished thickness of epidermis, hyperkeratosis, pigmentation and parakeratosis. Conclusions In conclusion, these data suggest that CP can decrease symptoms of ACD.

• Physical Therapy Rehabilitation Science
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• 제2권2호
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• pp.63-69
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• 2013

Objective: To assess the effect of vitamin D administration on the skin blood flow response to occlusion and heat. Design: Cross-sectional study. Methods: Twenty age matched subjects; 10 who had diabetes and 10 who were controls were administered 4,000 IU of vitamin D3 for 3 weeks at breakfast. The function of the endothelial cells was evaluated in 2 ways; first, the response to 4 minutes of vascular occlusion of the skin was measured with a laser Doppler flow meter. Second, the skin blood flow response to local heat at 42 degrees C for 6 minutes was examined. Results: The results of the experiments showed that the blood flow response to heat was reduced after 3 weeks administration of vitamin D in the subjects with diabetes and in the control subjects (p<0.05). The response to occlusion was not significantly different within each group before and after vitamin D administration, but the group with diabetes had a significantly lower blood flow response to occlusion than did the controls (p<0.05). Conclusions: Acute doses of vitamin D may impair nitric oxide production and reduce blood flow to tissue during stressors in people with diabetes.

• International Journal of Korean Welding Society
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• 제5권1호
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• pp.29-34
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• 2005

Finite element analysis (FEA) and experimental studies on an elastic bending method have been performed in order to control the angular distortion at the fillet weldment for curved panel. Process parameters for the elastic bending method such as clamping span and release time were analyzed with reference to welding condition and geometric effect of the curved panel, which can minimize or prevent the angular distortion by producing a proper skin stress to the fillet weldment. The amounts of the angular distortion decrease almost in a linear manner with an increase in the skin stress. The skin stress required for non-angular distortion at the fillet weldment is strongly dependent on the plate thickness, not the heat intensity applied. The clamping span for obtaining uniform skin stress was defined as functions of the plate thickness and length of the free edge. Clamp should be removed after the fillet weldment is cooled down to room temperature for non-angular distortion. Effectiveness of the elastic bending method established was verified by its application to an actual curved panel.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제12권4호
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• pp.201-202
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• 2008

Because of the importance of suction or injection in the fields of aerodynamics, space science and many other industrial applications, our present study is motivated. The effect of natural convection on MHD flow past a vertical plate with suction or injection is studied. We have tried to solve the dimensionless governing equations by using finite difference scheme. To ensure the validity of our numerical solutions, we have compared our numerical solutions for temperature and velocity for the case of suction and injection for unit Prandtl number with the available exact solutions in the literature. The corresponding codes were written in Mathematica 5.0 for calculating numerical solutions for temperature and velocity and the comparison between the exact and numerical solutions. For the purpose of discussing the results some numerical calculations are carried out for non-dimensional temperature T, velocity u, skin friction ${\tau}$ and the Nusselt number $N_u$, by making use of it, the rate of heat transfer is studied.

• 대한기계학회논문집
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• 제18권9호
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• pp.2431-2442
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• 1994

In this paper the efficient space marching Viscous Shock Layer and Parabolized Navier-Stokes method have been applied to study the complex 3-D hypersonic equilibrium chemically reacting flowfilelds over sphere-cone($10^{\circ}$) vehicle at low angles of attack($0^{\circ}~5^{\circ}), Mach 20, and an altitude of 35km. The current bluntbody/afterbody space marching numerical method predicts the complex flowfields accurately and efficiently even on a small computer. The shock thickness from equilibrium air model is thinner than that from the perfect gas model. The windside wall heat-transfer rate, pressure and skin friction force were increased significantly when compared with those of leeside. The CA, CN, CM were increased almost linearly with the angle of attack in this region. The wall pressure, heat transfer, skin friction and axial force coeffient from equilibrium model were much higher than those from perfect gas model. The center of pressure moved forward with the increase of angle of attack.

• Journal of Photoscience
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• 제5권1호
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• pp.39-43
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• 1998

Pulsed Er: YAG and CO$_2$ lasers induced temperature rise of tissue is studied using axisymmetric, two-dimensional, and transient Pennes bio-heat equation for elucidating the implications of skin resurfacing. Modeling indicates that Er:YAG laser induced temperature has much higher but more shallow distribution in tissue than that of the CO$_2$ laser because of much higher absorption coefficient. The increase of repetition rate does not much affect on temperature rise because these laser modalities have much shorter heat diffusion time than the temporal length of each off-pulse. This model works as a tool to understand the photothermal effect in the laser-tissue interaction.

• 한국산업융합학회 논문집
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• 제5권1호
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• pp.81-89
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• 2002

The objective of this paper is to clarify the combined effect of heat conduction, air temperature and thermal radiation on the person seated on the floor under operation of floor heating system. Experiments were conducted for summer seasons under 8 kinds of condition: combinations of air temperature $20^{\circ}C$, $22.5^{\circ}C$ and floor temperature $20^{\circ}C$, $22.5^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$ and $40^{\circ}C$ under still air. Japanese and Koreans were adopted as subjects. To evaluate the effect of conduction operative temperature modified by heat conduction was derived from the human heat balance equation. New weighting coefficients were estimated from the modified operative temperature and modified mean skin temperature. As for thermal sensation the modified operative temperature more significantly correlated to that sensation each heat transfer processes. As the floor temperature is higher, the human conduction heat gain from floor increase and the dry heat from the human body decrease.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.61-72
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• 2003

In cosmetic area, retinol is prominent ingredient for anti-wrinkle but unstable against light, heat, oxygen and so on. Therefore the stabilization of retinol is required. Here, we capsulated doubly retinol in the SLM(Skin Lipid Matrix) that makes three dimensional lamellar structure similar to skin, after formation of primary liposome (retinol-nanoemulsion). First, we make primary liposome from retinol / hydrogenated lecithin / polysorbate20 / caprylic ＆ capric triglyceride / ethanol / and so on, and the mean diameter to 70 nm, using microfluidizer passed three times at 800 Bar, repeatedly. Then we produce DC-liposome (doubly capsulated-liposome) that was encapsulated primary liposome with SLM made of hydrogenated phosphatidyl choline / caprylic ＆ capric triglyceride / 1, 3-butylene glycol / ceramide3 / cholesterol /etc. We measured for color stability against light and heat with chromameter. As a result of this experiment, we observed DC-liposome was more than from 1.5 to 3 times as stable as general liposome. Livability of retinol has improved from 2 to 6 times when we analyzed it by HPLC. Also, penetration effect of DC-liposome has improved.

• Radiation Oncology Journal
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• 제2권1호
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• pp.1-9
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• 1984

To evaluate the influence of prior heat treatment on the thermal enhancement of irradiation effect after hyperthermia, an experimental study was carried out using a total of 80 mice. Hyperthermia was carried out at $43^{\circ}C$ for 40 minutes and was repeated with various intervals. A single dose of 3,000 rad was delivered on skin of mouse tail immediately after the second hyperthermia. The skin changes of the irradiated mouse tail were observed from 7th to 35th post-irradiation days, and the skin scores were analyzed. The results are as follows, 1. The radiation damage on mouse skin increased significantly when radiation was combined with hyperthermia. 2. The radiation damage after repeated hyperthermia is significantly less than that after single hyperthermia, when the interval is 1 to 6 days. 3. As a result, thermal tolerance persists from 1 through 6 days after the initial hyperthermia.