• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.629-632
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• 2009

The polymeric desiccant rotor is made from the super absorbent polymer by ion modification. The moisture sorption capacity of the super desiccant polymer(SDP) is 4 to 5 times larger than those of common desiccant meterials such as silica gel or zeolite. It is also known that SDP can be regenerated even at the relatively low temperature. To fabricate the desiccant rotor, firstly the SDP was laminated by coating the SDP on polyethylene sheet. Then corrugated and rolled up into a rotor. The diameter, the depth, the dimensions of the corrugated channel, etc. were pre-determined from numerical simulation on the heat and mass transfer in the desiccant rotor. The dehumidification performance was tested in a climate chamber. The relevant tests were carried out at the process air inlet temperature of $32^{\circ}C$, the regeneration air inlet temperature of $60^{\circ}C$ and the inlet dew-point temperature of both the process air and the regeneration air of $18.5^{\circ}C$, when the rotation period is long, the moisture sorption is not effective. In the desiccant rotor developed in this study, the optimum rotation period is found about 350s at the regeneration temperature of $60^{\circ}C$. It was found from further experiments that the optimum rotation tends to decreases as the regeneration temperature increases. Meanwhile, the outlet temperature of the process air deceases monotonically as the rotation period increases.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.1
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• pp.30-41
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• 1999

This study was conducted to verify the advantages of Gal-Ot. Gal-Ot is defined the clothings dyed with persimmon juice. Firstly the physical properties of fabrics were examined. Secondly the wear tests were conducted. The wear tests were performed in climatic chamber controlled 3$0^{\circ}C$ air temperature 50$\pm$5% R.H and 0.2m/s air movement. Four women subjects participated in this experiment and 4 times experiments were performed per one subject. The expeimental schedule was planned following 4 steps that is sedentary posture during 30 minutes-walking the 5。slope treadmill by 70m/min during 20 minutes-sedentary posture during 20 minutes-standing posture on toward the blowing wind during 10 minutes. The results obtained is as folows : The insulation of fabric was increased with dyeing with persimmon juice. The air permeability of fabric was remarkably increased with dyeing with persimmon juice. The mean skin temperatures of subjects were apt to be higher in wearing Gal-Ot than undyed clothing. The clothing micro temperature of subjects were slightly inclined to become lower in wearing Gal-Ot than undyed clothing, The clothing micro humidity was decreasee when: the subjects were gal-Ot than wore undyed clothing, And then it brought about more comfortable on wear sensation. The differences of physiological reactions were not consistent between clothing types except for sweat rate on the back. This result may be attributed the to complex experimental schdules consisted of four steps and to a little difference between open type and close type. However I consider that the clothing type of Gal-Ot is suitable for open type because Gal-Ot is summer wear for blocking the sultry heat.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.1
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• pp.3-13
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• 1999

This study was performed for purpose of getting fundamental information requisite to wear velvet clothes that is more comfortable for the human body and also the environment. It was carried out in a human wearing test and thermal manikin test at the same time in a controlled-condition chamber. The experimental environment had a ambient temperature of 15$\pm$0.5$^{\circ}C$ with the relative humidity at 5$^{\circ}C$$\pm$5% and with air velocity at less that than 0.2m/sec. Velvet differ from common plain weaves in thermal properties because it's constructed in two parts one is ground part and the other part is pile part. In order to investigate the thermal resistance of velvet eight different combination of 4 velvet kinds and 2 lings kinds as experimental clothes. [(4 velvet kinds : Acetate cuprammoium Rayon Cotton Wool) (2 lining kinds : acetate viscose rayon)longrightarrow8 combination: Aa, Av, Ra, Rv, Ca, Cv, Wa, Wv: the simplified character] The results of this study can be summarized as follows : 1. For the regional thermal resistance the differences in eight clothes as well as differences in each part were significant. As a whole the breast part showed the highest thermal resistance and the leg part was higher than the shank part. The rank of the total thermal resistance was put at Wa>Wv>Ca>Cv>Aa>Av>Ra>Rv in this order. 2. Considered clothing microclimate microclimate temperature has a similar tendency to the total thermal resistance. It showed a significance in the differences of eight clothes and each parts. the belly part was highest in every combination. On the other hand for clothing humidity there was a significance between back and breast part only in the human wearing test. 3. It was indicated that CLO value was highly positively correlated with the clothings' weight and showed a high negative correlation with the air permeability.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.2
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• pp.292-304
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• 2006

The Atrophy of lung among chronic asthenia disease is a kind of tuberculosis. It is divided in two types. One is the Atrophy of lung with consumptive fever, the other is the Atrophy of lung with consumptive cold. Four prescriptions can be used treat this disease. Pulmonary abscess(肺癰) is infected by poisonous fatcors of wind and heat. It's symptoms like coughing, chest pain, fever and phlegm with pus after coughing are appeared generally, in case of serious condition, pyemia after coughing can be appeared. This disease is applicable to lung abscess, bronchiectasis, lung gangrene. Six prescriptions can be used to treat this disease. Coughing and congestion of the head(咳嗽上氣) is called Lung-distension(肺腸). Its symptom is dyspnea caused by more expiration rather than inspiration. This disease is divided into two types like chronic asthenia type and inflammatory type. Seven prescriptions can be used to treat this disease.

• Journal of Technologic Dentistry
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• v.22 no.1
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• pp.113-128
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• 2000

The purpose of this study was to serve as a basis for the development of dental technology and for creating a condition that dental technicians could work with pride and right values, by examining what problems there were in their health care, what they thought about them, and how the problems could be solved, The findings of this study were as below: 1. The most serious and harmful element in dental technology workshop was a dust(57.5%) and a noise(33.3%). 2. Approximately 99.0% of the dental technicians investigated made a complain of air pollution caused by noise. Their opinion on a possible measure to remove noise air pollution was that the noise-generating machine should be replaced(64.1%) or that it should be isolated(28.8%). 3. 76.0% complained air pollution cause by dust deteriorates their working efficiency. As a way to eliminate it, they suggested a dust chamber(35.3%) or an air cleaner(27.5%) should be installde. 4. About 80% made a complain of gas air pollution. The most common related symptom was a headache(56.9%). They thought that gas-generating machine should be isolated(39.9%) or that an air purifier should be prepared(33.3%). 5. The largest impact of heat and light on their body was weakening their eyesight(56.9%). 47.1% got burn once though four times, and 34.3% did five times or more. The way to prevent them was to install an automatic casting machine(66.0%) or use protective glasses(28.1%). 6. Approximately 47.7% were considering a change of occupation, and the most common reason was heavy work(23.5%), followed by poor prospect(21.6%) and working environment(19.0%) in the order named. 7. 88.9% responded they were likely to have an occupational disease. Their idea about the proper frequency of regular health examination was once a year(53.6%), or once per every six months(41.8%). 8. The field they were most interested in was health care(39.2%), followed by academic research activities(31.4%). This fact indicated it's most urgently required to improve their working environment.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1159-1163
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• 2006

This experiment was performed to examine the influences of high ambient temperature on milk production, nutrient digestibility, energy and protein sufficiency ratio, and plasma metabolites concentration in lactating cows. In a $2{\times}2$ crossover design, four multiparous lactating Holstein cows were maintained in a chamber under treatment of constant moderate ($18^{\circ}C$) ambient temperature (MT) or high ($28^{\circ}C$) ambient temperatures (HT). The DMI and milk protein yield were significantly lower in HT (p<0.05). The milk yield, milk lactose yield, and milk SNF yield tended to be lower in HT (p<0.10). No statistical differences for 4% fat-corrected milk and milk fat yield were observed. Rectal temperatures were significantly higher in HT than MT (p<0.05). The apparent DM, OM, ether extract, CF, and ash digestibility did not differ between treatments. On the other hand, the apparent CP digestibility was increased significantly (p<0.05) and nitrogen free extract tended to increase (p<0.10) in HT. The sufficiency ratio of ME and DCP intake for each requirement tended to be lower in HT than in MT (p<0.10). Concentrations of total protein (TP), albumin, and urea nitrogen in plasma did not differ between treatments. Plasma 3-methylhistidine (3MH) concentration as a marker of myofibrillar protein degradation tended to be higher in HT (p<0.15). In conclusion, high ambient temperature was associated with a lower energy and protein sufficiency ratio, and decreased milk protein production, even though the body protein mobilization tended to be higher.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.7
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• pp.1129-1136
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• 2008

The gaiter is one of the personal protective equipments worn in various industrial sites. This study was performed on humans to investigate the physiological strain of wearing gaiters and to compare control gaiters that are currently on the market and new gaiters that are developed for alleviating heat stress. Experiments were conducted in a climatic chamber of WBGT $30.0\pm0.7^{\circ}C$ under five differed experimental conditions: None, Control A, Control B, New A, New B. The results were as follows. The temperature inside gaiters was significantly lower in both New A and New B than in both Control A and Control B and the difference between news and controls was 1$^{\circ}C$ (p<.01). The humidity inside gaiters in both New A and New B were higher than that in Control A, and lower than that in Control B (p<.01). The outermost surface temperature of the gaiter was the lowest in None and it increased in the following order: New B < New A < Control A < Control B. Mean skin temperature was higher by 0.14$^{\circ}C$ in wearing gaiters than in no gaiters. Skin temperatures in lower body were lower in Control than in New and skin temperature in upper body were higher in Control than in New (p<.01). Local sweat rate, total weight loss and subjective sensations did not show a significant difference according to the gaiters. It was concluded that wearing gaiters affected distribution of skin temperature and local sweat rate.

• Journal of Animal Science and Technology
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• v.47 no.2
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• pp.253-260
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• 2005

This study was conducted to utilize the wastes produced from thinning the forest as a roughage source for ruminants. Four ruminally cannulated Korean steers were used to investigate the ruminal fermentation characteristics and blood concentrations of stress-related hormones. Treatments were composed of the rice straw only (Control) and the 30% pine silage plus 70% rice straw(Pine silage) as roughages. The experiment was conducted with four replicates by a double tum over design. For sampling of blood under high temperature steers were accommodated in respiratory chamber. Concentrations of ruminal pH, volatile fatty acids and ammonia were not affected by substitution of pine silage. Mean concentration of blood thyroxine was significantly(P < 0.01) lower in the pine silage than the control. However, blood cortisol concentration was not affected by substitution of pine silage, even though it was significantly(P < 0.05) decreased after exposure for 6 hrs in high temperature. It was concluded that the pine silage using the wastes produced from thinning the forest could be use as a substitute roughage for reduction of heat stress in ruminant.

• Tunnel and Underground Space
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• v.25 no.2
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• pp.144-154
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• 2015

Mechanical energy is accumulated in the object when stress is exerted on rock specimens, and the failure is occurred when the stress is larger than critical stress. The accumulated energy is emitted as various forms including physical deformation, light, heat and sound. Uniaxial compression strength test and point load strength test were carried out in low temperature environment, and thermal variation of rock specimens were observed and analyzed quantitatively using thermal infrared camera images. Temperature of failure plane was increased just before the failure because of concentration of stress, and was rapidly increased at the moment of the failure because of the emission of thermal energy. The variations of temperature were larger in diorite and basalt specimens which were strong and fresh than in tuff specimens which were weak and weathered. This study can be applied to prevent disasters in rock slope, tunnel and mine in cold regions and to analyze satellite image for predicting earthquake in cold regions.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.2
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• pp.193-198
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• 2017

Rubber materials are widely used for anti-vibration in various industries such as railways, automobile, and aviation. However, various factors hinder the accurate prediction of mechanical properties and lifetime of these materials. Particularly, a stress softening phenomenon Mullins effect greatly affects the accuracy of test results by reducing the initial peak stress. Although the Mullins effect has been studied previously, research on its temperature dependence is lacking. In this study, we performed experiments to estimate the temperature dependence of the Mullins effect. Dumbbell specimens made of natural rubber (NR65) was mounted on a stress softening tester and placed in a heat chamber, where they were tested at temperature of 25, 50, and $80^{\circ}C$. Further, five test sets, each consisting of 10 loading/unloading cycles were sequentially performed at predetermined time intervals. Based on the test results, we assessed the effect of temperature and time interval on stress softening and recovery.