• Korean Journal of Remote Sensing
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• v.28 no.2
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• pp.203-214
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• 2012

The physical environment of urban areas covered mostly by concrete and asphalt is the main cause of the urban heat island effect, primarily becoming apparent through increased land surface temperature. This study examined the effect of different urban land cover types on the land surface temperature using MODIS, Landsat ETM+ and RapidEye satellite data. As a result, the remote sensing based land surface temperature showed a marked difference according to the land use pattern in the case study of Ilsan new city. The high-rise apartment residential districts with less building-to-land ratio and higher green area ratio revealed lower land surface temperature than the low-story single-family housing districts characterized by relatively high building-to-land ratio and low green area ratio. From the view of climate zone and land cover types, there is a strong linear correlation between the impervious land cover ratio and the land surface temperature; the land surface temperature increases as the impervious built-up areas expand. In contrast, vegetation;water and shadow areas affect the decrease of land surface temperature. There is also a negative (-) correlation between NDVI and land surface temperature but the seasonal variation of NDVI can be hardly corrected.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.11a
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• pp.19-19
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• 2007

• Korean Journal of Agricultural Science
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• v.42 no.3
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• pp.231-235
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• 2015

This study was performed to investigate the change of the body surface temperature during socialization of weaning pigs. A total of 108 piglets (Landrace 60 and Yorkshire 48) aged 31 (${\pm}1.1$) day was used for this study. Experiment was designed as follows; familiar group (T1), randomly mixed with unfamiliar piglets (T2), mixed based on weight of unfamiliar piglet (T3). The transport and mixing of pigs were performed at 10:00, and then body surface temperature was taken by thermo-graphic camera after 4 hours (14:00). Average surface temperature and hot-spot-temperature, which is the hottest spot of the body surface, were analyzed using Testo IRsoft 3.1 software. Average temperature of body surface were 36.0, 38.2, and 37.5 in T1, T2, and T3, respectively. Average of body surface temperature in T2 and T3 were higher (p<0.001) than T1, and average temperature of body surface of T3 was greater (p<0.001) than that of T2. The hot-spot-temperature of T1, T2, and T3 were 38.7, 39.5, and 39.6, respectively. The hot-spot-temperature of T2 (p<0.01) and T3 (p<0.001) were significantly higher than that of T1. Above results demonstrate that grouping unfamiliar pigs leads to increase in the body temperature possibly by pigs aggressive behavior during social conflict. By the result on average body temperature, this study suggests that the mixing with similar body weight would increase the struggle time and frequency.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.4
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• pp.511-517
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• 1993

Changes of the surface and interface tension with temperature for washing liquids and alkanes were measured by FACE surface tensiometer. Using the extended Fowkes' equation, the dispersion and polar force components of the surface tension were estimated. The results were as follows : 1. The surface tensions of washing liquids and alkanes decreased almost linearly with the increase of temperature. 2. The interface tensions of 0.25% DBS/alkane increased slowly with the increase of temperature. In the case of nonionic surfactant solutions, however, the interface tensions with alkanes varied with the number of hydrophilic ethylene oxide(EO) groups. 3. Of the surface tension of water at $20^{\circ}C$, the dispersion force component was 25.3 dyn/cm and the polar force component was 47.8 dyn/cm. As the temperature increased, both the polar and dispersion force components decreased in a similar fashion. 4. The dispersion force component of surface tension of 0.25% DBS solution was 30.0 dyn/cm, and the polar force component was 2.2 dyn/cm at $20^{\circ}C$. The two components decreased with the increase of temperature. 5. As the temperature increased, the dispersion force component of surface tension decreased and the polar force component increased significantly for 0.25% NPPG-7.5EO solution. In the case of 025% NPPG-10EO, both the dispersion and polar force components decreased slowly, but the polar force component is expected to increase from $60^{\circ}C$. However, the polar force component of surface tension decreased with the increase of temperature for 025% NPPG-15EO solution, and at the temperature higher than $60^{\circ}C$ the surface tension is expected to be composed of only dispersion force component.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.06a
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• pp.251-257
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• 2000

A numerical simulation of the temperature rise for sliding surface in dry contact is based on Jaeger's formula combined with a calculated heat input. A gear tooth temperature analysis was performed. The pressure distribution has the Hertzian pressure distribution on the heat source. The heat partition factor is calculated along line of action. A Temperature distribution of tooth surface is calculated about before and after profile modification. A Temperature of addendum and deddendum in modified gear have reduced.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.757-762
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• 2002

Many reports have been shown that the buoyancy, electromagnetic force, surface tension, and gas shear stress are the driving forces of weld pool circulation in arc welding. Among them, the surface tension of molten metal plays an important role in the flow in weld pool, which are clarified by the specially designed experiments with small particles as well as the numerical simulations. The surface tension is also related to the penetration in arc welding. Therefore, a quantitative evaluation of surface tension is demanded for the development of materials and arc process control. However, there are few available data published on the surface tension of molten metals, since it depends on the temperature and the composition of materials. In this study, a new method was proposed for the evaluation of surface tension and its temperature dependence, in which it is evaluated by the equilibrium condition of acting forces under a given surface geometry, especially back surface. When this method was applied to the water pool and to the back surface of molten pool in the stationary gas tungsten arc welding of thin plate, following results were obtained. In the evaluation of surface tension of water, it was shown that the back surface geometry was very sensitive to the evaluation of surface tension and the evaluated value coincided with the surface tension of water. In the measurement of molten pool in the stationary gas tungsten arc welding, it was also shown that the comparison between the surface tension and temperature distribution across the back surface gave the temperature dependent surface tension. Applying this method to the mild steel and stainless steel plates, the surface tension with negative gradient for temperature is obtained. The evaluated values are well matched with ones in the published papers.

• Carbon letters
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• v.11 no.2
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• pp.131-136
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• 2010

Propellant waste was impregnated on the surface of activated carbon fiber and heat-treated at different temperature to introduce newly developed functional groups on the ACF surface. Functional groups of nitrogen and oxygen such as pyridine, pyridone, pyrrol, lacton and carboxyl were newly introduced on the surface of modified activated carbon fiber. The porosity, specific surface area, and morphology of those modified ACFs were changed as increasing the heat-treated temperature from 200 to $500^{\circ}C$. The optimum heat-treatment temperature was suggested to $500^{\circ}C$, because lower temperature given rise to the decrease of specific surface area and higher temperature resulted in the decrease of weight loss. Propellant waste can be used as an useful surface modifier to porous carbons.

• Journal of the Korean Wood Science and Technology
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• v.35 no.3
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• pp.22-28
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• 2007

Using woodceramics made from sawdust board of pine thinning logs, changes in surface temperature were investigated, by the heating rate and keeping time at maximum temperature. The heating rate of $2^{\circ}C/min$ and keeping time at maximum temperature 1 hour, were the highest in surface temperature. Also, it was found that woodcermics maintained heat for a long time because the descending velocity of their surface temperature was slower than that of the heater.

• Journal of Welding and Joining
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• v.20 no.1
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• pp.69-75
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• 2002

This study investigated the effect of the system parameters on penetration depth measurement using infrared temperature sensing system. The distance from focusing lens to detector was varied to diminish the error in measuring weld bead width. The effect of bead surface shape on measured surface temperature profile was evaluated using specimen heated by electric resistance. The measuring distance from laser beam was changed to optimize the measuring point. The results indicated that the monitoring device of surface temperature using infrared detector array was applicable to real time penetration depth control.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.35-44
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• 2017

PURPOSES: This study suggests a specific methodology for the prediction of road surface temperature using vehicular ambient temperature sensors. In addition, four kind of models is developed based on machine learning algorithms. METHODS : Thermal Mapping System is employed to collect road surface and vehicular ambient temperature data on the defined survey route in 2015 and 2016 year, respectively. For modelling, all types of collected temperature data should be classified into response and predictor before applying a machine learning tool such as MATLAB. In this study, collected road surface temperature are considered as response while vehicular ambient temperatures defied as predictor. Through data learning using machine learning tool, models were developed and finally compared predicted and actual temperature based on average absolute error. RESULTS : According to comparison results, model enables to estimate actual road surface temperature variation pattern along the roads very well. Model III is slightly better than the rest of models in terms of estimation performance. CONCLUSIONS : When correlation between response and predictor is high, when plenty of historical data exists, and when a lot of predictors are available, estimation performance of would be much better.