• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.585-588
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• 2008

Thermal mixing phenomena in a Y-type microchannel were investigated using a micro-PIV. Two inlet reservoirs of the microchannel were controlled individually so that the characteristics of thermal mixing in the channel with temperature difference were compared with those without the difference. The velocity field in the mixing process was measured using the micro-PIV system that includes an ICCD (Intensified CCD) camera. The mixing area and uniformity were also analyzed. It is observed that the flow fluctuation in spanwise direction is induced by temperature difference, which enhances mixing process in microchannels.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.481-484
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• 2004

A form of measured temperature distribution to estimate condition of a electrical apparatus is a absolute reference for condition of the apparatus, time rate of transition, and difference between reference and currently temperature. Because passive thermography which has not injection of external thermal stimulation shows difference of temperature being on surface of a structure and temperature difference between the structure and back ground, the result could apply only to estimation or monitor for condition of terminal relaxation and overload related with temperature rising. However, a thermal flow in active thermography is differently generated by structure and condition of surface and subsurface. This paper presents the nondestructive testing using the properties and includes the results by heat injection and cooling to the apparatus. The buried discontinuity of subsurface could be detected by these techniques.

• 농업과학연구
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• 제38권1호
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• pp.115-120
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• 2011

20% of total energy use to sustain temperature of building inside. In this reasons, researchers effort to improve the thermal insulation capacity with new wall system. Using appropriate materials and consisting new wall system should considered in energy saving design. OSB(Oriented strand board), Larch lining board used to consist wall system. $2{\sim}6$ Larch lining board has tongue & groove shape for preventing moisture. Comparing with gypsum board and green timber lining board as interior sheathing material, temperature difference of Green timber wall system was bigger than temperature difference of gypsum board wall system. This aspects indicate that Green timber wall system was revealed higher thermal insulation property than gypsum board wall system. Gypsum board portion transfer heat easily because temperature difference gradient of gypsum board wall system was smaller than OSB wall system. Total temperature variation shape of G-4-S and G-6-S show similar model but, temperature variation shape in green timber wall portion assume a new aspect. The purpose of this study was that possibility of thermal insulation variation and new composition of wall system identify to improve thermal insulation performance. In the temperature case, this study shows possibility of improving thermal insulation performance. Humidity, sunshine and wind etc. should considered to determine building adiabatic properties.

• 한국주거학회논문집
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• 제24권1호
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• pp.51-59
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• 2013

This study aims to improve the thermal comfort level of detached housing area by reducing the impact of thermal environment. The study focused on reducing surface temperature that is generated in buildings and adjacent spaces as a result of sensible heat load and presented a proposal on implementing planting method considering its outdoor condition and structure and composed materials. To perform the study, we utilized 3D-CAD to examine the outdoor condition and structure and composed materials that impact on surface temperature and conducted space design after reflecting climatic elements in simulations. The result is as follows. In reviewing temperature distribution of Heat Island Potential (HIP) of buildings and adjacent spaces, in case where green coverage ratio is increased, there was a $6^{\circ}C$ temperature difference and in regard to changes in the thermal environment in detached housing area, in case where rooftop planting, surface improvement, planting, and overall green coverage ratio is increased, there was a $10^{\circ}C$ temperature difference. In addition, there was difference in temperature in detached housing area following the changes in wind.

• KIEAE Journal
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• 제14권3호
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• pp.79-86
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• 2014

Studies have shown that the thermal performance of buildings changes depending on the year of construction completion. It leads to increased energy consumption of buildings and significant financial burden on users. Thus, this study has calculated the thermal insulation performance of 86 apartments quantitatively, using temperature difference ratio and sensible heat flux. Also, energy consumption characteristics depending on the year of construction completion and thermal insulation performance were analyzed by comparatively analyzing the results of insulation performance evaluation and heating costs. The analysis results are as follows. As for thermal insulation performance, it was around 70% lower in the apartments completed before 1985, compared to apartments completed after 2010. As for heating costs, the apartments with the highest heating cost incurred 1.5 higher heating cost than the apartment with the lowest heating cost. In terms of the insulation performance evaluation, the difference was 2.5-fold.

• 한국지열·수열에너지학회논문집
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• 제17권4호
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• pp.36-45
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• 2021

In this study, to improve the indoor thermal environment of the radiant floor heating system, a study was conducted on the temperature change characteristics and energy consumption according to the change of the indoor air set temperature, the supply hot water temperature and the outdoor temperature. As for the control method, the on/off control and the thermal difference proportional control method proposed through previous studies were applied. In addition, in consideration of field applicability, numerical analysis was performed for the case where the indoor air temperature sensor was affected by the wall temperature. As a result, it was found that the temperature difference proportional control method is more effective for thermal comfort and energy saving than on/off control.

• 한국구조물진단유지관리공학회 논문집
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• 제17권3호
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• pp.145-152
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• 2013

본 논문은 1990년대~2011년 시공 중이었던 건축물의 커튼월의 단열성을 평가하기 위하여 내외 표면 온도를 측정하여 부위별 온도 차이를 분석하였다. 유리면이나 단열층이 있는 표면보다 커튼월의 프레임 (멀리온 및 트랜섬)의 온도는 동절기 외부 평면의 경우 $6^{\circ}C{\sim}10^{\circ}C$ 정도 높게 나타났다. 또한, 같은 프레임에서도 앵커유닛이 있는 부위가 다른 프레임보다 $2^{\circ}C{\sim}3^{\circ}C$ 더 높게 나타나 보다 큰 열 손실이 일어나고 있는 것으로 나타났다.

• 한국주거학회논문집
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• 제19권1호
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• pp.89-96
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• 2008

This study measured the thermal environment and residents' control behaviors of cooing according to 3 groups of household type-families with preschool children, families of middle age and families of senior. The object of this study are to fmd the difference of the actual condition of indoor thermal environment and cooling control behavior by age or household type and to develop user oriented climate control system. The results were summarized as follows. When the age of members at household is younger, the indoor mean temperature and temperature that people turned off the air conditioner became lower. These different indoor thermal environment of each group means that younger generation is familiar with cooler from their early age and these early uses of cooler made them prefer cooler condition than family of senior. Therefore, this results show that different indoor thermal environment is influenced by factors such as household type and metabolism difference and so on.

• 설비공학논문집
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• 제14권11호
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• pp.890-896
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• 2002

Purpose of this study is to clarify the evaluation of thermal comfort based on temperature differences between outdoor and indoor thermal conditions in summer. The experiments were performed to evaluate temperature difference between indoor and outdoor thermal conditions (29, 31, $33^{\circ}$) by physiological and psychological responses of human. According to physiological responses, TSV (thermal sensation vote) and CSV (comfort sensation vote) and psychological responses, ECG (electrocardiogram), MST (mean skin temperature) of human, it was clear that the optimum temperature difference is about $5^{\circ})\;and\;7^{\circ}$).

• Steel and Composite Structures
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• 제27권6호
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• pp.777-788
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• 2018

An investigation on the thermal buckling resistance of simply supported FGM beams having parabolic-concave thickness variation and temperature dependent material properties is presented in this paper. An analytical formulation based on the first order beam theory is derived and the governing differential equation of thermal stability is solved numerically using finite difference method. a function of thickness variation is introduced which controls the parabolic variation intensity of the beam thickness without changing its original material volume. The results showed the high importance of taking into account the temperature-dependent material properties in the thermal buckling analysis of such critical beam sections. Different Influencing parametric on the thermal stability are studied which may help in design guidelines of such complex structures.