• Title/Summary/Keyword: Surface Temperature

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A Change in Surface Temperature of Ceramics Made from Board Mixed with Sawdust and Rice Husk - Effect of Resin Impregnation Rate and Carbonization Temperature - (톱밥과 왕겨 혼합보드로 제조된 세라믹의 표면 온도 변화 - 수지함침율 및 탄화온도의 영향 -)

  • Oh, Seung-Won;Park, Hee-Jun
    • Journal of the Korean Wood Science and Technology
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    • v.38 no.1
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    • pp.43-48
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    • 2010
  • This study was aimed at offering basic data to develop a new use of sawdust and rice husk. The results of this study were as follows: In surface temperature of ceramics by resin impregnation rate, the velocity was great in the early time of heat transfer because the temperature precipitously increased to 10 minutes elapsed. Also, the surface temperature of ceramics manufactured in resin impregnation rate of 60~70% indicated the highest. Heat transfer was fast in terms of the changes in surface temperature of ceramics according to the carbonization temperature, as because the density of ceramics made on condition of the carbonization temperature of $1000^{\circ}C$and $1200^{\circ}C$ was high. Moreover, ceramics maintained heat for a long time because the descent velocity of surface temperature of ceramics was slower than that of heater.

Comparison Study on the Estimation Algorithm of Land Surface Temperature for MODIS Data at the Korean Peninsula (MODIS 자료를 이용한 한반도 지표면 온도산출 알고리즘의 비교 연구)

  • Lee, Soon-Hwan;Ahn, Ji-Suk;Kim, Hae-Dong;Hwang, Soo-Jin
    • Journal of Environmental Science International
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    • v.18 no.4
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    • pp.355-367
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    • 2009
  • Comparison study on the land surface temperatures, which are calculated from four different algorithms for MODIS data, was carried out and the characteristics of each algorithm on land surface temperature estimation were also analysed in this study. Algorithms, which are well used for various satellite data analysis, in the comparisons are proposed by Price, Becker and Li, Ulivieri et al., and Wan. Verification of estimated land surface temperature from each algorithm is also performed using observation based regression data. The coefficient of determination ($R^2$) for daytime land surface temperature estimated from Wan's algorithm is higher than that of another algorithms at all seasons and the value of $R^2$ reach on 0.92 at spring. Although $R^2$ for Ulivieri's algorithm is slightly lower than that for Wan's algorithm, the variation pattern of land surface temperature for two algorithms are similar. However, the difference of estimated values among four algorithms become small at the region of high land surface temperature.

Development and Evaluation of Statistical Prediction Model of Monthly-Mean Winter Surface Air Temperature in Korea (한반도 겨울철 기온의 월별 통계 예측 모형 구축 및 검증)

  • Han, Bo-Reum;Lim, Yuna;Kim, Hye-Jin;Son, Seok-Woo
    • Atmosphere
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    • v.28 no.2
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    • pp.153-162
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    • 2018
  • The statistical prediction model for wintertime surface air temperature, that is based on snow cover extent and Arctic sea ice concentration, is updated by considering $El-Ni{\tilde{n}}o$ Southern Oscillation (ENSO) and Quasi-Biennial Oscillation (QBO). These additional factors, representing leading modes of interannual variability in the troposphere and stratosphere, enhance the seasonal prediction over the Northern Hemispheric surface air temperature, even though their impacts are dependent on the predicted month and region. In particular, the prediction of Korean surface air temperature in midwinter is substantially improved. In December, ENSO improved about 10% of prediction skill compared without it. In January, ENSO and QBO jointly helped to enhance prediction skill up to 36%. These results suggest that wintertime surface air temperature in Korea can be better predicted by considering not only high-latitude surface conditions (i.e., Eurasian snow cover extent and Arctic sea ice concentration) but also equatorial sea surface temperature and stratospheric circulation.

Establishment of Optimum Floor Surface Temperature Floor in Ondol Heating System (온수온돌 난방시 바닥면의 중성온도 설정에 관한 연구)

  • 공성훈
    • Journal of the Korean housing association
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    • v.6 no.2
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    • pp.51-55
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    • 1995
  • This study presents a real neutral floor surface temperature in floor panel heating system(Ondol). The Ondol heating system can keep the constant temperature. However, the actual temperature when a person sits on a floor can be different from the surface temparature of a floor it self. The contents of this study are as follows : 1) measuring the spatial distributions of thermal conditions 2) the thermal sensation vote of residents is taken in order to investigate the relation between thermal condition and human thermal sensation in sedentary condition 3) estimating the neutral floor surface temperatures by measuring floor surface temperatures.

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A Quantitative Study on the Effect of Temperature Control by a Shade Tree and the Lawn Area (식물의 온도 완화효과에 관한 기초적 연구)

  • 안계복;김기선
    • Journal of the Korean Institute of Landscape Architecture
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    • v.14 no.1
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    • pp.1-13
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    • 1986
  • The purpose of this study is to investigate the effect of temperature control by a shade tree and the lawn area. In this investigation, we find out that artificial-lawn, concerte, and exposed soil are more higher temperature than covered with plant materials. The results of the measurement may to summerized as follows; 1) Low-temperature effects of zoysia japonica is more controlled by condition of growth than leaf length of grass. Surface temperature make 0.7$^{\circ}C$ difference between long grass (15cm), and short grass (5cm), but make 5$^{\circ}C$ difference between good growth grass (230/10$\textrm{cm}^2$) and bad growth grass (80/10$\textrm{cm}^2$). 2) The surface temperature of the lawn area is 40.5$^{\circ}C$ lower on a maxinum than that of the artificial lawn (July 28, 1985). During the day of summer, shade area under the shade tree is 0.9$^{\circ}C$ lower then lawn area surface temperature, 6.9$^{\circ}C$ lower than bad growth lawn, 10.3$^{\circ}C$ lower than exposed soil, and 18$^{\circ}C$ lower than concrete surface temperature. 3) Natural irrigation effect on the surface temperature fluctuation. But this effect is changed by compositions of ground materials and time-lapse. 4) Sunny day is more effective than cloud day. 5) In summer season, surface temperature make a difference compare to temperature of 0.5-1.5m height from ground : Surface temperature is 3.4$^{\circ}C$ lower at the lawn area (11 a.m.), 4.2$^{\circ}C$ lower at the shade area the shade tree, 12.7$^{\circ}C$ higher at the concrete area (3p.m.), 38.8$^{\circ}C$ higher at the artificial lawn (2p.m.) 6) According to compositions of ground materials and season have specific vertical temperature distribution curve. 7) In summer season, temperature distribution of 0.5-1.5m hight at the shade tree is 4.8-5.7$^{\circ}C$ lower than concrete area (noon-3p.m.)

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SPECTRAL LINE-DEPTH RATIO AS A PRECISE EFFECTIVE TEMPERATURE AND SURFACE GRAVITY INDICATOR FOR WARM STARS

  • Kim, Chul-Hee
    • Journal of The Korean Astronomical Society
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    • v.39 no.4
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    • pp.125-128
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    • 2006
  • In order to determine the precise effective temperature and surface gravity of warm stars, all synthetic spectral lines in the wavelength range of $4000-5700{\AA}$ with T=6000-7750 K, and log g=3.5, 4.0, and 4.5 for [M/H]=0.0, $V_{rot}$=10 km $s^{-1}$, and $V_{tubl}$=2 km $s^{-1}$ were calculated using the SYNSPEC package(Hubeny, et al., 1995) and the Kurucz(1995) model. Then, the depth-ratios for all line pairs were investigated and we selected two and six depth-ratios appropriate for the surface gravity and temperature indicators, respectively. We plotted six grids with X- and Y-axes for the depth-ratios of surface gravity and temperature, respectively, for the simultaneous estimation of these two atmospheric parameters. This method was applied to the spectum of $\delta$ Scu for the determination of its temperature and surface gravity simultaneously.

Effects of Stainless Steel Plate-Patterns on the Thermal Distortion and Surface Temperature of Aluminum Frypan (알루미늄 프라이팬에 부착된 스텐리스판의 패턴이 열 변형 및 표면온도에 미치는 영향)

  • Moon, Sungmo;Yoon, Myungsik
    • Journal of the Korean institute of surface engineering
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    • v.53 no.5
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    • pp.227-231
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    • 2020
  • This article investigated the effects of stainless steel plate-patterns bonded to aluminum frypan on the thermal distortion and surface temperature of the frypan during gas or induction heating. Two different stainless steel plate-patterns were employed: type A contains only circular holes and type B has not only circular holes but also vacant spaces of 0.5 mm thick and 40 mm long straight line crossing 60 mm long curved line. The bottom of the frypan was distorted during heating when type A stainless steel plate-bonded frypan while no significant thermal distortion was observed for type B stainless steel plate-bonded frypan during heating. Temperature of the frypan surface showed the same trend during gas heating, irrespective of stainless steel plate-patterns. During induction heating, however, the frypan with type B stainless steel plate-pattern showed lower surface temperature than the frypan with type A stainless steel plate-pattern. It is concluded that Type B stainless steel plate-pattern with circular holes and vacant spaces of lines is very effective for minimizing a thermal distortion and lowering the surface temperature of an aluminum frypan during induction heating.

Analyzing the Relationship between Climate Change and Anchovy Catch using a Cointegration Test (공적분 검정을 이용한 기후변화의 멸치 생산량에 대한 영향 분석)

  • EOM, Ki-Hyuk;KIM, Hong-Sik;HAN, In-Seong;KIM, Do-Hoon
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.6
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    • pp.1745-1754
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    • 2015
  • This study aimed to analyze the relationship between sea temperatures and anchovy catch of Anchovy drag net fishery using annual time series data from 1970 to 2013. In the analysis, time series data on variables (CPUE, sea surface temperature, and 10m temperature) were estimated to be non-stationary from unit root tests, but one long-term equilibrium relation among variables was found from a cointegration test. From an exclusion test, a 10m temperature would not have relations with CPUE and sea surface temperature. The result of regression analysis on sea surface temperature and anchovy catch indicated that the sea surface temperature would have positive impacts on the anchovy catch. It means that when the sea surface temperature would increase, all other things including the current level of fishing effort being equal, the catch of anchovy was predicted to increase. More specifically, the result showed that when 1% of sea surface temperature increases, CPUE would be increased by 2.81%.

Seasonal Prediction of Korean Surface Temperature in July and February Based on Arctic Sea Ice Reduction

  • Choi, Wookap;Kim, Young-Ah
    • Atmosphere
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    • v.32 no.4
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    • pp.297-306
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    • 2022
  • We examined potential seasonal prediction of the Korean surface temperature using the relationships between the Arctic Sea Ice Area (SIA) in autumn and the temperature in the following July and February at 850 hPa in East Asia (EA). The Surface Air Temperature (SAT) over Korea shows a similar relationship to that for EA. Since 2007, reduction of autumn SIA has been followed by warming in Korea in July. The regional distribution shows strong correlations in the southern and eastern coastal areas of Korea. The correlations in the sea surface temperature shows the maximum values in July around the Korean Peninsula, consistent with the coastal regions in which the maximum correlations in the Korean SAT are seen. In February, the response of the SAT to the SIA is the opposite of that for the July temperature. The autumn sea ice reduction is followed by cooling over Korea in February, although the magnitude is small. Cooling in the Korean Peninsula in February may be related to planetary wave-like features. Examining the autumn Arctic sea ice variation would be helpful for seasonal prediction of the Korean surface temperature, mostly in July and somewhat in February. Particularly in July, the regression line would be useful as supplementary information for seasonal temperature prediction.

Analysis of Relationship between Vegetation Cover Rates and Surface Temperature Using Landsat TM Data (Landsat TM 데이터에 의한 식생피복율과 지표면온도와의 관계 해석)

  • Park, Jong-Hwa;Na, Sang-Il;Kim, Jin-Su
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2005.10a
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    • pp.569-573
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    • 2005
  • Land surface temperature(LST) is one of the key parameters in physics and meteorology of land-surface processes on regional and global scales. Urban Heat Island(UHI), a meteorological phenomenon by which the air temperature in an urban area increases beyond that in the suburbs, grows with the progress of urbanization. Satellite remote sensing has been expected to be effective for obtaining thermal information of the earth's surface with a high resolution. The main purpose of this study is to produce LST map of Cheongju and to analyze the spatial distributions of surface heat fluxes in urban areas. This study, taking Cheongju as the study area, aims to examine relationship between vegetation cover rates and surface temperature, and to clarify a method for calculation surface temperature with Landsat TM thermal images.

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