• Title/Summary/Keyword: 열적 공간 대표성

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Test of Therrml Spcial Representativity Using Satellite based Land-Surface Temperature (위성기반의 지표면 온도를 활용한 기상관측소의 열적 공간 대표성 테스트)

  • Lee, Chang-Soek;Han, Kyung-Soo;Yeom, Jong-Min;Park, Yoon-Young
    • Proceedings of the KSRS Conference
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    • 2007.03a
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    • pp.228-233
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    • 2007
  • 지표면 온도(Land Surface Temperature, LST)는 지표와 대기간의 수증기 교환을 조절하는 중요한 기상변수중의 하나이다. 그 외에도 지표면 온도는 토양의 상태나 식생의 성장에도 밀접한 관계가 있어 임업과 농업에도 널리 활용되고 있다. 본 연구의 목적은 위성 지표면 자료를 이용하여 지상관측점의 열적 공간 대표성을 알아내는 것이다. 전국에총 76개의 관측소가 있으며 그중에서 선정된 6곳 의 관측소(서울,부산,대전,대구,광주,춘천)를 MODIS LST product와 비교를 하였다. 비교 방법은 위성 자료의 pixel size를 $3{\time}\;3$, $5{\time}\;5$, $7{\time}\;7$, $9{\time}\;9$, $11{\time}\;11$, $15{\time}\;15$, $19{\time}\;19$, $25{\time}\;25$로 변환하여 각 pixel size별 평균값을 계산하여 MODIS product와 비교하여 선형분석을 하였다. 분석의 요소로 Fraction Vegetation Cover(FVC)와 Digital Elevation Model(DEM)을 사용하였으며 분석 결과 FVC의 상관관계과 DEM보다 높은 상관성을 보여주었다. 선형분석으로 도출한 식으로 지표면 온도를 재산출한 뒤 지상관측값과의 RMSE를 산출하였다. 대표성 규명을 위한 RMSE는 일 최고 기온 산출 모델에 관한 연구를 참고하여 $^{\circ}C$로 결정하였다.

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Thermal Spatial Representativity of Meteorological Stations using MODIS Land Surface Temperature (MODIS 지표면온도 자료를 이용한 기상관측소의 열적 공간 대표성 조사)

  • Lee, Chang-Suk;Han, Kyung-Soo;Yeom, Jong-Min;Song, Bong-Geun;Kim, Young-Seup
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.3
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    • pp.123-133
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    • 2007
  • Thermal spatial representativities of meteorological stations over Korea have been investigated using land surface temperature (LST) based on MODerate resolution Imaging Spectroradiometer (MODIS) satellite observation. The linear regression method was used to estimate air temperatures from MODIS LST product. To compare MODIS LST with observed air temperatures at six meteorological stations, the mean values of MODIS LST with nine given window sizes were calculated. In this case, the position of centered pixel in each given window size is correspond to that of each meteorological station. We also applied $4^{\circ}C$ threshold for RMSE comparison, which is based on a analogous study on daily maximum air temperature model using satellite data. In this study, the results showed that each station has a different representativity; Deajeon $15km{\times}15km$, Chuncheon $11km{\times}11km$, Seoul $7km{\times}7km$, Deagu $5km{\times}5km$, Kwangju $3km{\times}3km$, and Busan $3km{\times}3km$.

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A Study of Correlation between Air Environment Index and Urban Spatial Structure: Based On Land Use and Traffic Data In Seoul (대기오염지수와 도시공간구조 특성에 관한 연구: 서울시 토지이용과 교통자료를 바탕으로)

  • Lee, Won-Do;Won, Jong-Seo;Joh, Chang-Hyeon
    • Journal of the Economic Geographical Society of Korea
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    • v.14 no.2
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    • pp.143-156
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    • 2011
  • Recently, the environmental problems become a serious social issue, there are many efforts to manage it efficiently. As one of the ways to measure the environment in quantitative index, the environmental indicators are used in decision-making process. Air Environmental Index(AEI), which is derived from the U.S. Air Quality Index(AQI), illustrates the degree of air pollution. In study as follows: to find the charateristics of administrative dongs in Seoul, correlation analysis is conducted based on the land-use patterns and daily traffic data that represent AEI and urban spatial structure of Seoul.

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Temperature Log in Boreholes (착정공 온도검층의 이용)

  • 염병우;김형찬
    • Journal of the Korean Society of Groundwater Environment
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    • v.4 no.2
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    • pp.73-77
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    • 1997
  • Temperature log is an effective method for evaluating the thermal situation and ground water flow path within boreholes. When pumping is proceeding, the continuous temperature logs in a neighboring holt are very helpful to assess connectivity between holes. Mean geothermal gradient is calculated as 26.6$^{\circ}C$/km from 400 bottom hole temperatures, their depths, and the annual mean temperature at each location. Various examples of temperature logs in crystalline rocks are described: first examples show linear increases in homogeneous granitic rocks. Another one illustrates that isolated aquifers have connected each other after a borehole is completed. Slopes of temperature gradient indicate ground water inlet and/or outflow within a borehole. The other log concludes that thermal response in observation borehole induced by pumping is related to the location of interconnected fractures.

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Thermal Transient Response of a PWR Pressurizer Vessel Wall for the Inadvertent Auxiliary Spray Transient (PWR 가압기에서 오동작 보조살수 과도시 용기벽의 열적 과도응답)

  • Jo, Jong-Chull;Lee, Sang-Kyoon;Shin, Won-Ky;Cho, Jin-Ho
    • Nuclear Engineering and Technology
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    • v.23 no.2
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    • pp.183-199
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    • 1991
  • Transient response of temperature distributions in a Pressurized Water Reactor (PWR) pressurizer vessel wall for the Inadvertent Auxiliary Spray transient has been analyzed with conservatism accounted for the resulting thermal stresses in the regions of the vessel wall which are wetted by the spray water droplets. In order to determine the forced convective heat transfer coefficient at the inner boundary surface of vessel wall where the droplets impinge on and flow down, the transient temperatures of spray droplets when they reach the inner surface of the vessel wall after travelling from the spray nozzle through the pressurizer interior space occupied with the saturated steam-noncondensable hydrogen gas mixture have been predicted. The transient temperature distributions in the vessel wall have been obtained by using the finite element method, and the typical results have been provided. It has been shown that the results of thermal analysis are consistent with representation of the input transient and have plausible physical meaning.

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A Study of Hierarchical Stepwise Migration and Depopulation : focusing on city rank-size and NIR change, 1995~2014 (도시 계층성에 따른 단계적 이동과 과소화 검토 -1995~2014년 도시 순위-규모와 자연적 인구증가율 변화를 중심으로-)

  • Lee, Chung Sup;Eun, Seog In
    • Journal of the Korean association of regional geographers
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    • v.22 no.1
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    • pp.120-134
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    • 2016
  • This study aims to investigate the hierarchical stepwise migration and its influences on regions (metropolitan areas, cities and counties of Korea administrative district) through analyzing the city rank-size and the changes of natural increase of population. The result shows that the inter-regional migration has been associated to the decrease of the population and the decline of NIR in the regions where outflows have been persisted. Also, theses demographic events have sequentially occurred through the hierarchy of settlement system: gradually from rural (gun) and lower ranked regions in the system of city rank-size, to urban (si) and regions in the high ranks in the system. Based on the result of this study, it is possible to understand and expect the major origins of inter-regional migration, the presence of the hierarchical stepwise migration and most significantly, the spatial expansion of depopulation problems.

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