• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1400-1404
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• 2005

This paper presents the temperature control of aluminum plate by using Peltier element. Peltier effect is heat pumping phenomena by electric energy as one of the thermoelectric effect. So if current is charged to Peltier element, it absorbs heat from low temperature side and emits heat to high temperature side. In this experiment, Peltier element is used to control the temperature of small aluminum plate with current control and operating cooling fan only while cooling duration. Operating cooling fan only while cooling duration is proper to get more rapid heating and cooling duration. As a result of experiment, it takes about 100sec period to repeating temperature between $35^{\circ}C$ and $70^{\circ}C$ and about 80sec from $40^{\circ}C$ to $70^{\circ}C$ in ambient air temperature $25^{\circ}C$ and while operating cooling fan only in cooling duration. Future aim is to apply this temperature control method in actuating SMHA(special metal hydride actuator) which is applicable in Siver project acting in low frequency range by using Peltier element for heating and cooling.

• 한국의류학회지
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• 제32권6호
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• pp.991-998
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• 2008

본 연구는 상변화물질의 농도가 의복내 공기충의 온도변화에 미치는 영향을 연구하고자 하였다. 상변화물질로는 노나데칸을 사용하였으며 농도는 아크릴 바인더 대비 10%, 20%, 30%로 조절하여 면직물에 코팅처리하였다. 동적 열전달 측정장치인 Human-Clothing-Environment Simulator을 사용하여 고온에서 저온 이동시 다시 고온이동시의 의복내 온도변화를 측정하였다. 외부 환경온도는 고온은 34도, 저온은 5도와 10도를 하였으며 먼저 34도에서 한시간 동안 컨디셔닝한 후에 5도 또는 10도에 30분 동안 노출시켜 의복내 온도변화를 측정하였고 다시 34도에 노출시켜 30분동안 의복내 공기층에서의 상변화물질의 열적거동을 살펴보았다. 그 결과 상변화물질처리된 직물로 이루어진 의복내 공기층은 고온에서 저온이동시 상변화물질의 발열효과로 인해 미처리 직물보다 높은 온도를 나타내었으며, 저온에서 고온이동시에는 흡열효과로 인해 미처리 직물보다 온도상승이 느리게 나타났다. 농도가 증가할수록 상변화물질에 의한 발열효과는 증가하는 것으로 나타났으며 흡열효과의 경우에는 20%에서 큰 변화를 갖는 것으로 나타났다. 농도변화에 따른 미처리와 처리직물 사이의 차이를 보면, 10%에서 20% 증가시에 나타난 차이가 20%에서 30% 농도변화시에 나타난 차이보다 크게 나타났다. PCM 처리된 모든 직물들이 상변화를 겪는 것은 아니었으며 직물층에 따라 상변화를 하였고 최외곽층의 경우에는 상변화물질에 의한 흡열발열현상외에도 외부로의 열손실을 겪기 때문에 이에 대한고찰이 있어야하는 것을 알 수 있었다.

• Journal of Mechanical Science and Technology
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• 제19권12호
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• pp.2245-2252
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• 2005

Thermal stratification in the branch piping of power plants can be generated by turbulent penetration or by valve leakage. In this study, a numerical analysis was performed to estimate the thermal stratification phenomenon by in-leakage in the SIS branch piping of nuclear power plant. Leakage rate, leakage area and leakage location were selected as evaluation factors to investigate the thermal stratification effect. As a result of the thermal stratification effect according to leakage rate, the maximum temperature difference between top and bottom of the horizontal piping was evaluated to be about 185K when the valve leakage rate was about 10 times as much as the allowed leakage rate. For leakage rate more than 10 times the allowed leakage rate, the temperature difference was rapidly decreased due to the increased mixing effect. In the result according to leakage area, the magnitude of temperature difference was shown in order of $3\%,\;1\%\;and\;5\%$ leakage area of the total disk area. In the thermal stratification effect, according to the leakage location, temperature difference when leakage occurred in the lower disk was considerably higher than that of when leakage occurred in the upper disk.

• 대한원격탐사학회지
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• 제26권6호
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• pp.675-680
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• 2010

Temperature is one of the main issues in climate change, and the urban heat island effect in highly developed urban areas is an important issue that we need to deal with. This study analyzed the extent of the cooling effects of urban green spaces. The study used a surface temperature map of Seoul. It found that the cooling effects of green space was observed within limited distances, although it varied a little depending on the parks investigated. The cooling effect distance ranged from 240m to 360m, averaging about 300m. It also found the size of an urban green space does not make much difference in cooling the surrounding areas. Although further investigation with diverse urban areas should be conducted on this matter, the results did imply that many small green spaces in the neighborhood are more effective than a single big green space in mitigating the heat island effects of cities.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.401-406
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• 2005

In this paper, both effect of TiN-coating and effect of temperature in TiN-coating by arc ion plating on surface characteristics of TiN coated SKH51 steel are investigated by experiments. Hardness, surface roughness, TiN coating thickness and adsorption force are measured in order to evaluate the effects. For evaluation of the experimental data, the two-way ANOVA method is used. It is concluded that the furnace temperature in the rang of $400^{\circ}C\~500^{\circ}C$ in AIP processing has very little influence on the TiN coating of the SKH51 steels.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2003년도 춘계학술대회 논문집
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• pp.41-46
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• 2003

In recently, Is inhabiting more than 70％ indoors during a day in case of company employee and ordinary people which is looking at usual business. Therefore Thermal comfort of human body about indoor temperature and air flow acting very heftily. When intestine temperature is fallen for external low temperature and air flow in winter in case enter into heated room feel comfort by effect of temperature and feel comfort or discomfort by room heating condition gradually. Therefore it is important that grasp thermal comfort about temperature and air flow in heating to keep continuous comfort in indoor dwelling. Temperature and thermal comfort factor of emotion ＆ sensitivity image exert fair effect since heating middle although thermal comfort change greatly effect on sensation about temperature at actuality heating early. Need much study yet in vantage point of emotion ＆ sensitivity although much study were held about thermal and comfort sensibility and when heat in existing research until now. Therefore this study is targeting that evaluate thermal comfort through introduction of estimation method by emotion ＆ sensibility image real and synthetic sensibility about thermal environment that is becoming winter heating.

• Steel and Composite Structures
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• 제45권6호
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• pp.851-863
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• 2022

This research deals with the study of the Thomson heating effect in magneto-thermoelastic homogeneous isotropic rotating medium, influenced by linearly distributed load and as a result of modified couple stress theory. The charge density is taken as a function of the time of the induced electric current. The heat conduction equation with energy dissipation and with hyperbolic two-temperature (H2T) is used to formulate the model of the problem. Laplace and Fourier transforms are used to solve this mathematical model. Various components of displacement, temperature change, and axial stress as well as couple stress are obtained from the transformed domain. To get the solution in physical domain, numerical inversion techniques have been employed. The Thomson effect with GN (Green-Nagdhi) -III theory and Modified Couple Stress Theory (MCST) is shown graphically on the physical quantities.

• Structural Monitoring and Maintenance
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• 제3권4호
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• pp.335-347
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• 2016

One of major errors in flow rate measurement for two-phase flow using an Electrical Capacitance Sensor (ECS) concerns sensor sensitivity under temperature raise. The thermal effect on electrical capacitance sensor (ECS) system for air-water two-phase flow monitoring include sensor sensitivity, capacitance measurements, capacitance change and node potential distribution is reported in this paper. The rules of 12-electrode sensor parameters such as capacitance, capacitance change, and change rate of capacitance and sensitivity map the basis of Air-water two-phase flow permittivity distribution and temperature raise are discussed by ANSYS and MATLAB, which are combined to simulate sensor characteristic. The cross-sectional void fraction as a function of temperature is determined from the scripting capabilities in ANSYS simulation. The results show that the temperature raise had a detrimental effect on the electrodes sensitivity and sensitive domain of electrodes. The FE results are in excellent agreement with an experimental result available in the literature, thus validating the accuracy and reliability of the proposed flow rate measurement system.

• 한국환경과학회지
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• 제9권2호
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• pp.101-108
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• 2000

Through numerical experiment using simplified OSU-1D PBL(Oregon State University One-Dimensional Planetary Boundary Layer) model and field measurement, we studied the impacts of vegetation canopy on heat island that was one of the characteristics of local climaate in urban area. it was found that if the fraction of vegetation was extended by 10 percent, the maximum air temperature and the maximum ground temperature can come down about 0.9${\circ}C$, 2.3${\circ}C$, respectively. Even though the field measurement was done under a little unstable atmospheric condition, the canopy air temperature was lower in the daytime, and higher at night than the air and ground temperature. This result suggests that the extention of vegetation canopy can bring about more pleasant local climate by causing the oasis, the shade and the blanket effect.

• 한국수산과학회지
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• 제30권6호
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• pp.997-1004
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• 1997

The effect of the oceanic condition on variations of the catches of Alaska pollack (Theragra chalcogramma) in the East Sea (the Japan Sea) is examined using monthly catches data of this fish and temperature data during 1972 to 1991. Since 1973 the catches of Alaska pollack have gradually increased, showing a peak in 1981, and then rapidly decreased after 1986. A significant negative correlation was found between variations of the catches and the temperature at 50 m depth offshore Mukho. In 1981, the year of the highest catches in the study period, the water mass in the Eastern Korean Coastal Sea of the East Sea was extremely cold, while the year of poor catch, 1979, was much warmer than the annual mean temperature. The results show that the temperature variations around the Eastern Korean Coastal Sea play an important role in the variations of the catches of Alaska pollack, implying that the effect of the Tsushima Warm Current is also very important.