• 한국환경과학회지
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• 제17권8호
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• pp.907-918
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• 2008

In order to monitor the impact of high temperature which is seen frequently with climate change, we investigated the monthly change in globe temperature, air temperature, mean radiant temperature and effective radiant heat flow, because the four well reflect thermal radiation from bio-meteorological aspect. Both globe temperature and air temperature showed an increasing trend every month. Compared to air temperature, globe temperature had a wider range of temperature change and was more influenced by meteorological element such as precipitation. Diurnal trends of air temperature, globe temperature and the difference between their temperature had the lowest value before the sunrise and the highest around $1300{\sim}1500$ LST, showing the typical diurnal trends. Globe temperature and the difference between their temperature had a sharp increase around $1000{\sim}1100$ LST, maintained high value until 1700 LST and then reclined, though varied by month. The difference between globe temperature and air temperature was highly dependent on the amount of precipitation and clouds. The duration in which globe temperature was higher than air temperature was the lowest in July. Therefore the amount of precipitation was the most affecting, followed by the amount of clouds and wind. In order to find out the diurnal trends of temperature in city center and city outskirts, we assumed the roof of a concrete build ing as a city center, and the grass-covered observatory of the Gimhae International Airport as city outskirts. The diurnal trends of temperature in the two sites showed a strong correlation. The highest and lowest temperature also had the same trend.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.128-131
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• 2004

This paper is to investigate the mock up test results of mass concrete for transfer girder using setting time difference with super retarding agent(SRA) to reduce hydration heat. According to test results, the temperature history of plain concrete without placing lift had a steep rising curvature, and plain concrete had a big temperature difference between surface and middle section of mass concrete, which may result in occurrence of temperature crack. However, considering placing method B, because setting time of middle section concrete was retarded with an increase in SRA contents, higher hydration heat temperature was observed at surface section concrete compared with that at middle section concrete at early age, which can lower the possibility of hydration heat crack. In case of placing method C, although peak temperature of hydration heat was much lower, at early age, high crack occurrence possibility of the hydration heat attributable to the big temperature difference between middle section and bottom section of concrete was expected at bottom section concrete. Therefore, the structure above the ground like transfer girder is not applicable to consider the placing method C.

• 한국생활과학회지
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• 제5권2호
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• pp.123-130
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• 1996

The purpose of this study is to examine and to evaluate the wearing performance of pile materials to produce velvet fabrics which have excellent wearing comfort. Acetate velvet, Cuprammonium rayon velvet were combined as textiles for clothing and acetate and viscose rayon were as textiles for lining at the environmental condition of temperature $15^{\circ}C,\;18^{\circ}C,\;21^{\circ}C,\;24^{\circ}C$, relative humidity $50{\pm}5%$ and air velocity 0.25 m/sec. Wearing comfort among 4 materials combinations(Aa, Av, Ra, Rv) was examined and compared. The results are as follows. The investigation of mean skin temperature for environmental temperature and material combinations showed that the mean temperature had a significant difference at the p<0.01 level in accordance with environmental temperature and material combinations.(Aa>Av>Ra>Rv) Moreover, in clothing climate only clothing temperature tended to increase almost linearly but at $24^{\circ}C$ there was no significant difference among textiles for lining compared with the other environmental temperatures. In subjective sensations thermal sensation and comfort sensation showed a significant difference in environmental temperatures and materials.(Aa>Av>Ra>Rv) Though a subject felt warmer, more humid, and more uncomfortable at $24^{\circ}C$ for all of the material combinations comparing with the other temperatures, there was no significant difference in materials.

• 한국정밀공학회지
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• 제16권8호
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• pp.46-52
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• 1999

Large valves for steam turbines of fossil power plants are exposed to a severe mechanical and thermal loading resulting from steam with high pressure and high temperature. Valve casings are designed to withstand such a loading. During the operation of a plant, temperatures at inner and outer surface of the casings are measured and steam flow is controlled so that the measured difference is lower than the maximum allowable value determined in the design stage. In this paper, a method is presented to calculate the maximum allowable temperature difference at the inner and outer surface of valve casings for steam turbines of fossil power plants. The finite element method is used to analyze distribution of temperature and stresses of a casing under the operating condition. Low cycle fatigue and creep rupture are taken into consideration to determine the maximum allowable temperature difference. The method can be usefully applied in the design stage of the large valves for the steam turbines, contributing to safe and reliable operation of the fossil power plants.

• Computers and Concrete
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• 제26권4호
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• pp.343-350
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• 2020

Concrete-filled steel tubular (CFST) members have been widely used in engineering, and their tube diameters have become larger and larger. But there is no research on the thermal field of large-diameter CFST structure. These studies focused on the thermal field of the large-diameter CFST structure under solar radiation. The environmental factors and the actual placement position were considered, and the finite element model (FEM) of the thermal field of CFST members under solar radiation (SR) was established. Then the FEM was verified by practical experiments. The most unfavorable temperature gradient model in the cross-section was proposed. The testing results showed that the temperature field of the large-diameter CFST member section was non-linearly distributed due to the influence of SR. The temperature field results of CFST members with different pipe diameters indicated that the larger the core concrete diameter was, the slower the central temperature changed, and there was a significant temperature difference between the center and the boundary. Based on the numerical model, the most unfavorable temperature gradient model in the section was proposed. The model showed that the temperature difference around the center of the circle is small, and the boundary temperature difference is significant. The maximum temperature difference is 15.22℃, which appeared in the southern boundary area of the specimen. Therefore, it is necessary to consider the influence of SR on the thermal field of the member for large-diameter CFST members in actual engineering, which causes a large temperature gradient in the member.

• 한국의류산업학회지
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• 제2권5호
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• pp.423-429
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• 2000

This study was conducted to find out the relationship between skin temperature and clothing temperature in body parts. Four different kinds of fabrics were used in this experiment. These fabrics were a (Ny/Spun, 81.8/18.2%), b (Wool/Poly/span, 50/45/5%), (Wool/Ny/Span70/25/5) and d (Wool/Poly/Span 45/45/10%). The subjects skated at indoor ice rink where the length was 111.12 m, the temperature was $11{\pm}1^{\circ}C$ and the humidity was $70{\pm}10%$. The four an male professional skaters speed was $17{\pm}1$ seclm/lap. Physiological parameters were skin temperature at 4 body points (chest, upper arm, thigh, leg) and clothing temperature at chest was measured every 15 second. Experiment protocol was as follows: resting before skating (5 min.), skating (5 min.), and resting after skating (10 min.). The results were as follows; The mean skin temperature by fabrics shows b > a > d > c. The mean skin temperature began to decline little by little as soon as the subjects entered the indoor ice rink. After they rested for five minutes, they started skating and the mean skin temperature declined widely. After skating, the mean skin temperature increased step by step. It maintained the similar temperature. The value of skin temperature at body points shows Leg > Chest > Upper arm > Thigh. Because of the characteristics of skating uniforms, the skin temperature of the leg is the highest. The skating uniform was designed to have a protective portion in the leg. The chest produces the highest temperature in the body. The comparison of difference values in skin temperature show Thigh > Upper arm > Chest > Leg. While skating in a cold atmosphere, the largest difference value is clothing temperature. The clothing temperature is lower than the skin temperature during skating. The difference value of clothing temperature is larger than the skin temperature of the chest.

• 한국광학회지
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• 제13권3호
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• pp.240-244
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• 2002

광 위상지연기에서 두 편광축 사이의 위상차가 온도의 함수라는 현상을 이용하여 새로운 온도측정기를 제안하였다. 특정한 파장의 입력광이 일정한 길이의 광 위상지연기를 통과하면 온도에 따라 그 편광상태가 바뀌게 된다. 이때의 편광성분을 진행방향에 수직한 두 축 성분으로 분리하여 그 출력을 비교하면 광 위상지연기의 온도를 결정할 수 있다. 본 연구에서는 광 위상지연기로 길이 100mm의 편광유지 광섬유를 이용하여 온도측정기를 구현하였다. 온도에 대한 위상차 변화율은 0.236$^{\circ}C$$_{-1}$이었고, -2.6$^{\circ}C$~3.4$^{\circ}C$에서 $\pm$0.038$^{\circ}C$의 측정오차를 보였다.

• 한국환경과학회지
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• 제32권2호
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• pp.145-148
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• 2023

The purpose of this study was to investigate the changes in body temperature of canine via their hair lengths before and after grooming. A total of 120 companion canines were used in this study for a total of 6 weeks, and 20 dogs each week consisted of both 10 poodles and 10 malteses (five females and males). For accurate temperature measurement, the anal depth was measured at approximately 1.5 cm. Temperature before and after grooming was measured at 10 am and after more than three hours, respectively. There was statistical significance (p<0.05) in body temperature changes for male poodles at 1, 2, and 3 weeks and for female poodles at 1, 3, 4, and 5 weeks, and the total period showed a statistical difference for both male and female poodles (p<0.05). In addition, male and female malteses had an effect (p<0.05) on changes in body temperature at 1 and 6 weeks and only at 4 weeks, respectively. For total period, there was a statistical difference in male and female poodles (p<0.05). Moreover, when the temperature changes of females were compared, there was no remarkable difference. In conclusion, the body temperatures of both male and female dogs according to the length of their hair were lower after grooming than before grooming. The measurement of body temperature three hours after grooming, which could reduce stress or other factors, is judged to be able to help customers who are worried about clipping.

• Journal of Korean Neurosurgical Society
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• 제30권7호
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• pp.903-906
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• 2001

Objective : The brain temperature is about $0.4-1^{\circ}C$ higher than that of the other peripheral body area. But most of these results have been obtained in normothermic condition. The objective of this study is to evaluate the temperature difference between the brain and axilla, in patients under hypothermia. Methods : Sixty-three patients(37 women and 26 men) who underwent craniotomy with implantation of the thermal diffusion flowmetry sensor were included in this study. The temperature of the cerebral cortex and axilla was measured every 2 hours, simultaneously. The patient group was divided according to axillary temperature hyperthermia( over $38^{\circ}C$), normothermia($36-38^{\circ}C$) and hypothermia(under $36^{\circ}C$). Total 1671 paired sample data were collected and analyzed. Results : The temperature difference between the cerebral cortex and the axilla was $0.45{\pm}1.04^{\circ}C$ in hyperthermic patients, $0.97{\pm}1.1^{\circ}C$ in normothermic patients and $1.04{\pm}0.81^{\circ}C$ in hypothermic patients. The temperature difference has statistical significance in each group(unpaired t-test, p<0.05). Conclusion : From our study the temperature difference between the brain and the axilla in hypothermic condition increased more than that of normothermic state. And in hyperthermic condition, the temperature difference decreased.

• 설비공학논문집
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• 제3권5호
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• pp.365-375
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• 1991

Confined natural convection due to lateral temperature difference in rectangular enclosures was studied numerically and experimentally for the insulated and the constant temperature enclosures. In the case of insulated enclosure, the flow pattern and heat transfer modes are rather simple depending mainly upon Rayleigh number. In the case of isothermal enclosure, however, the phenomena of flow and heat transfer are somewhat complex and interesting due to the stable thermal gradients and various circumstances resulted from four wall temperature conditions. As a dimensionless variable, to describe properly the flow and heat transfer phenomena in the isothermal enclosure, temperature difference ratio ${\Delta}T_v/{\Delta}T_H$ is newly introduced and this parameter seems to be appropriate in the analysis of results on the effect of stabilizing thermal gradient.