• Atmosphere
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• v.21 no.4
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• pp.405-414
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• 2011

In this study, the influence of a change in land use on the local weather fields is investigated around the Lake Shihwa area using synthetic land cover data and a high-resolution mesoscale model - the Weather Research and Forecasting (WRF). The default land cover data generally used in the WRF is based on the land use category of the United States Geological Survey (USGS), which erroneously presents most land areas of the Korean Peninsula as savannas. To revise such a fault, a multi-temporal land cover data, provided by the Ministry of Environment of Korea, was employed to generate a land cover map of 2005 subject to the land use in Korea at that time. A new land cover map of 1989, before the construction of the Lake Shihwa, was made based on the 2005 map and the Landsat 4-5 TM satellite images of two years. Over the areas where the land use had been changed (e.g., from sea to wetlands, towns, etc.) due to the Lake Shihwa development project, the skin temperature decreased by up to $8^{\circ}C$ in the winter case while increased by as much as $14^{\circ}C$ in the summer case. Changes in the water vapor mixing ratio were mostly affected by advection and topography in both seasons, with considerable increase in the summer case due to continuous sea breeze. Local decrease in water vapor occurred over high land use change areas and/or over downstream of such areas where alteration in wind fields were induced by changes in skin temperature and surface roughness at the areas of land use changes. The albedo increased by about 0.1% in the regions where sea was converted into wetland. In the regions where urban areas were developed, such as Songdo New Town and Incheon International Airport, the albedo increased by up to 0.16%.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.1
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• pp.115-126
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• 2001

In this paper, through a series of comparative experiments, effects of two different cure processing methods, cocure and precure, on the mechanical properties of honeycomb core materials for aircraft applications are considered. Mass of moisture accumulated into the closed cells of the sandwich panel specimen from the measured mass of moisture diffused to the full saturation state into the elements(skin, adhesive layer, Nomex honeycomb), consisting the honeycomb sandwich specimen has been calculated. Water reservoir of 70$\^{C}$ was used to have specimens absorb moisture to see the influence of moisture absorbed into sandwich panel on its mechanical properties. For the repair condition holding for 2 hours at 177$\^{C}$(350℉) temperature, a pressure due to the vapor expansion in each cell of the sandwich panel, which may result in the local separation of the interface between laminated skin and the surface of the honeycomb, has been estimated by vapor pressure-temperature relation from the thermodynamic steam table and compared to the pressure from the ideal gas state equation. The bonding strengths of the laminated skins on the flat surface of the Nomex honeycomb have been compared by the flatwise tension test and climbing drum peel test performed at room temperature for dry, wet and wet-repair specimens, respectively.

• Fashion & Textile Research Journal
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• v.8 no.6
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• pp.727-732
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• 2006

The purpose of this study was to investigate the effects of flame-proof clothing on physiological responses and subjective sensation. We measured rectal temperatures, local skin temperature, clothing microclimate, blood pressure, heart rate, body weight loss and subjective sensation during 90 minutes (30 min of rest, 45 min of exercise and 15 min of recovery periods). Seven male subjects wore flame-proof clothing or reformed flame-proof clothing under the environmental condition of $35{\pm}1^{\circ}C$, $45{\pm}5%$ RH and $25{\pm}1^{\circ}C$, $50{\pm}5%$ RH. The results of this study were as follows; Rectal temperature, mean skin temperature, clothing microclimate and blood pressure were significantly lower levels in reformed flame-proof clothing. Heart rate and body weight loss were also showed lower levels. Subjects replied less hot, less uncomfortable and less wet in wearing a reformed flame-proof clothing. Our present results suggest that the ventilation through of gusset in underarm seam and zipper in sideseam of slacks are qualitatively useful for physiological needs.

• The Korean Journal of Physiology
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• v.3 no.1
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• pp.19-28
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• 1969

Skin temperatures on 10 sites and rectal temperature at every 10 minutes, oxygen consumption at every 20 minutes were measured on 18 male subjects (ages between 14 and 47 years) after exposure to cold air at $15^{\circ}C$ for two hours in a climatic room. Total body fat measured by means of a skinfold method and ratio of body surface area (S) to body volume (V), S/V, were utilized as basis of observations. Surface area was calculated after DuBois equation and body volume was calculated by our original formula. In influencing on the heat loss from the body core to the cold environment, % fat showed inverse relations, whereas, S/V ratio showed direct relations. Thus these two factors acted antagonistically on the body heat loss. Local skin temperatures showed negative correlations with skinfold thickness on the same site, nemaly, on chest, r=-.567; on back, r=-.507; and on upper arm, r=-.353. The other 7 skin sites showed low correlations with % fat. Minimum mean weighted skin temperature (MWST) showed a negative correlation (r=-.443) with % fat, and showed no correlation with S/V ratio. Oxygen consumption in the cold air at $15^{\circ}C$ increased from the first measurement at 20 minutes after exposure and maintained the same increasing trend up to 120 minutes. ${\Delta}T_R$ was greater in tile lean subjects who showed a greater % change in oxygen consumption. The antagonistic actions of % fat and S/V ratio on the heat loss were manifested by observations as follows: minimum rectal temperature was higher In fat subjects (r=.600) and lower in subjects with a greater S/V ratio (=-.582), ${\Delta}T_R$ was smaller in fat subjects (r=-.738) and greater in subjects with a greater S/V ratio (r=.618). Temperature difference between body core and skin surface (minimum rectal temperature minus minimum MWST) showed a positive correlation with % fat (r=.600) and a negative correlation with S/V ratio (r=-.881). Decrease in the mean body temperature and heat debt, respectively, showed negative correlations with % fat and positive correlations with S/V ratio.

• Journal of Magnetics
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• v.21 no.3
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• pp.476-489
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• 2016

In the present study, squeezing flow of micropolar nanofluid between parallel infinite disks in the presence of magnetic field perpendicular to plane of the disks is taken into account. The constitutive equations that govern the flow configuration are converted into nonlinear ordinary differential with the help of suitable similarity transforms. HAM package BVPh2.0 has been employed to solve the nonlinear system of ordinary differential equations. Effects of different emerging parameters like micropolar parameter K, squeezed Reynolds number R, Hartmann number M, Brownian motion parameter Nb, thermophoresis parameter Nt, Lewis number Le for dimensionless velocities, temperature distribution and concentration profile are also discussed graphically. In the presence of strong and weak interaction (i.e. n = 0 and n = 0.5), numerical values of skin friction coefficient, wall stress coefficient, local Nusselt number and local Sherwood number are presented in tabulated form. To check the validity and reliability of the developed algorithm BVPh2.0 a numerical investigation is also a part of this study.

• Fashion & Textile Research Journal
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• v.8 no.1
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• pp.123-128
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• 2006

For the purpose of examining the relationship of physiological and subjective responses to different exercise intensities and varied types of sportswear material, under environmental condition $20{\pm}1^{\circ}C$ $50{\pm}3%$RH, five men who wear four different kinds of sportswear which have same clothing cover area. The subjects exercised for 20 min with a 20 min pre-exercise rest period and another 20 min post-exercise recovery period. Throughout the 60 min. duration, we monitored the local skin temperature, rectal temperature, clothing microclimate and subjective sensation. The mean skin temperature was recorded to range from $33.5{\sim}34.1^{\circ}C$ for the entire duration of the experiment with the highest temperature observed at the 7th min after starting the exercise. During the exercise intensity at THR 20, the lowest recorded temperature was at the 5th min of the recovery time and stabilized at the 10th min. However, in the exercise intensity condition at THR 70, the temperature declined steadily until the end of the experiment. With regard to clothing materials, cotton 100% and Polyester/Cotton blended fabrics knit(35/65) was $0.5{\sim}0.7^{\circ}C$ maintained lower than Polyester 100% and polyester/Cotton blended woven fabrics (65/35). In the case of the rectal temperature at THR 70 in case of PET 100%, Polyester/Cotton blended woven fabrics (35/65) was higher $0.2{\sim}0.5^{\circ}C$ than other sportswear throughout the duration of the experiment.

• Journal of IKEEE
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• v.24 no.3
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• pp.913-916
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• 2020

In this paper, we propose the development of nitrogen cooling equipment for personalized local area. The proposed equipment consists of a cold air supply module, a body, and nitrogen injection with the following characteristics. First, it automatically controls the amount and time of cold air supply by utilizing information measuring skin temperature with volumetric temperature sensors, so it can have a competitive edge in function by ensuring complete safety. Second, if the distance measuring sensor is applied to the skin for more than a certain distance, it can block the cold air or control the discharge of nitrogen in conjunction with the control GUI to improve the efficiency of higher cooling therapy while providing safe management. Third, by installing a control module that can control the supply of nitrogen, the cost of maintenance can be minimized by minimizing the loss of nitrogen. Experiments at an external testing agency to evaluate the performance of the proposed equipment showed that the accuracy of the temperature sensor was measured in the range of ±3.8%, which is lower than the world's highest level(±5%), with a range of 110℃ to -160℃ similar to the world's highest level. Distance accuracy was measured in the range of ±3.0%, lower than the world's highest level(±5%), and weight accuracy in the range of ±0.1%, lower than the world's highest level(±5%). In addition, emission control was measured in four stages, higher than the world's highest level(stage 1) and nitrogen use was measured at 0.8L/min below the world's highest(6L/min). Therefore, the effectiveness of the methods proposed in this paper was demonstrated because they produced the same results as the world's highest levels.

• The Korean Journal of Pain
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• v.3 no.1
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• pp.27-33
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• 1990

In the past decades there has been a growth of interest in the use of stellate ganglion block (SGB) as part of the diagnosis and therapy for the disease of the head, neck and upper extremities. For the evaluation of changes in hemodynamics and temperature of the affected extremity after the SGB, unilateral SGB (either right or left) was performed by local injection of 10 ml of 1% lidocaine without epinephrine in 45 patients (right side SGB: 25, left side SGB: 20) with various diseases. Systolic and diastolic blood pressure, pulse rate and skin temperature of the ipsilateral hand were studied before and 1, 2, 3, 4, 5, 10, 15, 30 and 60 minutes after the block. The results were as follows: 1) Changes of blood pressure: Systolic and distolic blood pressure after either right or left side SGB showed no statistically significant change. 2) Changes of pulse rate: While the left side SGB showed a mild decrease without statistical significance, the right side SGB showed a statistically significant decrease at 30 and 60 minutes after the block (p<0.05). 3) Changes of skin temperature of the blocked hand: Either side SGB produced a gradual increase in temperature with time and showed statistical significance from 10 minutes in the left side block (p<0.01), and a from 10 minutes after the block in the right side (p<0.01). Both sides SGB showed a maximal increase at 30 minutes after the block and a small decrease at 60 minutes after the block compared to the 30 minutes value. 4) Despite the successful SGB. 4 of 45 patients failed to produce a significant increase in skin temperature on the affected upper extremity. In conclusion, unilateral SGB with 1% lidocaine at the 6th cervical vertebral level is a safe method for use on an outpatient basis, and an increase in skin temperature in the affected upper extremity is necessary to confirm the successful therapeutic effect on disease of the upper extremity.

• The Korean Journal of Community Living Science
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• v.18 no.4
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• pp.599-607
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• 2007

We analyzed the effects of regular Jjimjilbang (Korean sauna) exposure on the cold tolerance in young and elderly females. Subjects were young (n=7) and elderly (n=7) females who had never had Jjimjilbang exposure experience. The Jjimjil training group was exposured in the Jjimjilbang 19 times per week. Jjimjibang exposure was limited to three times per day. Jjimjil activity was taken freely. To prove the effects of the cold tolerance, subjects were exposed to cold air ($12{\pm}1^{\circ}C,\;60{\pm}10%$RH). In these conditions, subjects were exposed for 30 minutes at which time rectal temperature, skin temperatures, clothing microclimate, energy expenditure, blood pressure and subjective sensation were measured. To prove the effects of the local cold tolerance, vascular hunting reaction was observed measuring the finger skin temperature while the left middle finger tip was immersed in cold water of $0^{\circ}C$ for 30 minutes. The results are as follows. According to repeated Jjimjil exposure, rectal temperature changes, peripheral temperature and energy expenditure were increased gradually in the cold climate chamber. Blood pressure, subjective sensation and vascular hunting reactions did not show any significant difference. In conclusion, regular Jjimjilbang exposure has negative effects on the ability of the body to improve its regulation of temperature especially in cold tolerance.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.83-90
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• 2001

Cooling garments are being considered for reducing heat strain in hot environment. We evaluated the effectiveness of ice gel-based cooling vest in hot environment both resting and exercising. Four male subjects were exposed to heat(4$0^{\circ}C$, 50%RH) with vest or without it. The results were as follows; In case of the trial wearing ice gel-based cooling vest, total body weight loss, and local sweat volume were less than those without it. Mean skin temperature, rectal temperature, pulse, energy expenditure, temperature of inside clothes, and humidity of inside also were lower than those without cooling vest. By subjective thermal sensation, subjective humidity sensation, and thermal comfort sensation, it was proved that non-wearing vest decreased comfort than wearing that. These results suggested that wearing ice gel-based cooling vest reduced human heat strain in hot environment both resting and exercising.