• Journal of Urban Science
• /
• v.9 no.1
• /
• pp.17-31
• /
• 2020

This study aims to analyze the relations among greenbelt, urban land surface temperature empirically in order to assess the environmental effects of the greenbelt in the Seoul metropolitan area, objectively. For this purpose, this study conducts an empirical analysis of impacts of greenbelt on urban land surface temperature using a multiple-regression model. The main data employed in the analysis include real-time air pollution data, Landsat 8-OLI Landsat imagery data, KLIS data and Jip-gye-gu data. The major findings are summarized as follows. NDVI has a negative (-) correlation with the land surface temperature, and the urban temperature is high in areas with poor vegetation. The land surface temperature is low in residential or commercial areas, while the temperature is high in industrial areas. The temperature is low in green fields, open spaces, and river areas. it is found that the urban land surface temperature is low in the greenbelt zone. In the greenbelt zone, there is an effect that reduces the land surface temperature by 1% on average, as compared to that at the center of the Seoul metropolitan area. Especially, the center of the Seoul metropolitan area, in a range from 0.6% to 1.9% of the average temperature, the temperature gets lower up to approximately 3km from the greenbelt boundary.

• Journal of the korean Society of Automotive Engineers
• /
• v.4 no.3
• /
• pp.24-39
• /
• 1982

It has already been known that quenching effect is influenced greatly by stirring and changing coolant's temperature on quenching. But according to the past investigations its effect has not been taken into consideration quantitatively in the cooling process. The purpose of this study is that the influence of flow rate and temperature on the quenching effect of cooling water as quenching medium is quantitatively examined by using the open channel. The stream of water in this study is turbulent flow. The temperature of the specimen made of pure copper is measured by CA thermocouple in the vicinity of the surface and recorded by an automatic recorder during the quenching process in city water. The results obtained are as follows; 1. The quenching effect of cooling water generally increases with Reynolds Number(characteristic length; specimen diameter)as shown in the experimental formula; but at the realm of Reynolds Number from 1.2 * 10$^{4}$ to 9.2 * 10$^{4}$, the increasing rate of quenching effect shows little increase. 2. The increasing rate of quenching effect was increased under the flow rate of 221 cm/sec. On the other hand, it was decreased below this flow rate. 3. The quenching effect was influenced by the water temperature and the flow rate. But it was rather dependent upon the former than the latter. 4. Although the quenching effect appeared loosely in the water temperature of 50.deg. C, it was shown that the quenching effect increased in the low flow rate of 31 cm/sec. comparing with the still water. 5. It is desirable to design the quenching system to be over 1.2 * 10$^{4}$ in Reynolds Number or over, 3000$cm^{-1}$ / in V/v in order to increase the quenching effect of the system using open channel.annel.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.15 no.3
• /
• pp.936-943
• /
• 1991

• Smart Structures and Systems
• /
• v.25 no.2
• /
• pp.135-153
• /
• 2020

There has been a sustained interest towards the non-contact structural displacement measurement by means of videogrammetric technique. On the way forward, one of the major concerns is the spurious image drift induced by temperature variation. This study therefore carries out an investigation into the temperature effect of videogrammetric technique, focusing on the exploration of the mechanism behind the temperature effect and the elimination of the temperature-caused measurement error. 2D videogrammetric measurement tests under monotonic or cyclic temperature variation are first performed. Features of measurement error and the casual relationship between temperature variation and measurement error are then studied. The variation of the temperature of digital camera is identified as the main cause of measurement error. An excellent linear relationship between them is revealed. After that, camera parameters are extracted from the mapping between world coordinates and pixels coordinates of the calibration targets. The coordinates of principle point and focal lengths show variations well correlated with temperature variation. The measurement error is thought to be an outcome mainly attributed to the variation of the coordinates of principle point. An approach for eliminating temperature-caused measurement error is finally proposed. Correlation models between camera parameters and temperature are formulated. Thereby, camera parameters under different temperature conditions can be predicted and the camera projective matrix can be updated accordingly. By reconstructing the world coordinates with the updated camera projective matrix, the temperature-caused measurement error is eliminated. A satisfactory performance has been achieved by the proposed approach in eliminating the temperature-caused measurement error.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.20 no.3
• /
• pp.281-283
• /
• 1991

The effect of temperature on hysteresis of rough rice grown in Korea was investigated. The maximum hysteresis effect of Chucheongbyeo paddy rice at 5$^{\circ}C$ amounted to an average 1.7% moisure content. However, their values at $25^{\circ}C$ and 4$0^{\circ}C$ averaged 1.2% and 0.7% moisture, respectively. It may be suggested that the exteents of hysteresis are affected by the temperature of hysteresis are affected by the temperature of adsorption and desorption.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.6 no.1
• /
• pp.28-33
• /
• 2003

In this study, we observed air temperature to make clear that land coverage condition and stand form has a certain relationship to air temperature during the night in various green space. And with revolution analysis, we interpreted relationship of air temperature distribution in the green space, The way of analysis is this land coverage rate and air temperature, of number of tree volume of tree air temperature. With this experimental result, we can propose green plan, which is taking into consideration lower effect of air temperature. In this result, lower zone is formed in forest and water area, higher zone is formed in paved surface and barren ground. but this gap is a little. arbor+subarbor area, in the point of water area surrounded stand is formed relative lower air temperature. As a result to make up efficiency lower air temperature area, it is needed to make water area which has surrounded forest, and it is needed to make stand form lower air temperature 2~3 layer forest. In order of arbor, subarbor, shrub, the lower air temperature is more effect.

• The Korean Journal of Soil Zoology
• /
• v.5 no.2
• /
• pp.119-123
• /
• 2000

Effect of fluctuating temperatures on the development of the immature beet armyworm, Spodoptera exigua (H bner), was analyzed. At constant rearing temperature regimes, the estimated developmental threshold temperatures were varied among stages and instars, but had an average 13$^{\circ}C$ from egg hatch to adult emergence. Based on the 13$^{\circ}C$ threshold temperature, we set up three different rearing temperature regimes having the same day-degrees. Two fluctuating temperature regimes changed significantly the developmenta1 period expected by the constant rearing temperature regime. Under the same thermophase temperature (25$^{\circ}C$), the thermocycling regime with the higher cryophase temperature (10$^{\circ}C$) decelerated the developmental rate probably by lowering temperature limit thor development, but that with the lower cryophase temperature (5$^{\circ}C$) gave a negative developmental effect.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.03a
• /
• pp.361-367
• /
• 2009

The criteria such as ASTM recommends that the zero reading process of CPT must be performed in the same temperature condition with underground in order to reduce the effect of temperature. However, this method can not consider the change of temperature occurred during penetration. In this study, ultra small size temperature sensor with 0.5mm in diameter is manufactured to estimate and compensate the effect of temperature by using FBG sensor. The continuous temperature changes are monitored during cone penetration by using FBG temperature sensor installed in cone penetrometer. The temperature compensated tip resistances show the uniform and similar distributions with depth in different with originally measured tip resistance in cohesive soil. This study verifies that the tip resistances measured by previous zero reading method are affected by the change of underground temperature, and suggests the new temperature compensation technique using by FBG temperature sensor.

• Journal of Environmental Science International
• /
• v.13 no.7
• /
• pp.667-674
• /
• 2004

The objective of this study was to investigate the effects of pH and temperature on the formation of bromate, which is ozonation by-products, during ozonation. In this experiment, the operating parameters including pH 3 ～ 10 and temperature 15 ～ $30^{\circ}C$ were studied. Through the study for the bromate formation, reaction rate constant, and ozonation effect index on pH and temperature, the results obtained are as follows. At the same initial pH condition, the increase of pH shown similar trends even if the reaction variables such as temperature and reaction time of ozonation were exchanged. As pH and temperature were increasing, the bromate concentration was increased but bromine(HOBr+OBr) was decreased with increasing pH from 3 to 10. The activation energy(J/mol) for bromate formation decreased with increasing pH. The rate constants of bromate formation for the reaction of ozone and bromide, and ozone dosage coefficient$(K_{0})$ increased with temperature and pH. Ozonation effect index(OI) decreased with increasing temperature and pH.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.51 no.4
• /
• pp.561-566
• /
• 2015

In this study, the effect of temperature effect of the rubber matrix filled with nano sized silica particles composites with silica volume fraction of 19-25% was investigated by the Charpy impact test. The Charpy impact test was conducted in the temperature range from $-40^{\circ}C$ to $0^{\circ}C$. The critical energy release rate GIC of the rubber matrix composites filled with nano sized silica particles was considerably affected by temperature and it was shown that the maximum value was appeared at higher temperature between temperature tested and it was shown that the value of GIC increases as temperature tested increases. The major fracture mechanisms were matrix deformation, silica particle debonding and delamination, microcrack between particles and matrix, and/or pull out between particles and matrix which is ascertained by SEM photographs of Charpy impact surfaces fracture.