• 한국지리정보학회지
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• 제15권1호
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• pp.133-143
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• 2012

본 연구는 창원시 도시지역을 대상으로 도시공간을 고려한 야간시간대의 도시열섬특성을 파악하기 위해 1:1,000 축척의 토지이용도 및 토지피복도와 DTM, 그리고 ASTER 위성영상에서 추출된 야간시간대의 지표온도자료를 활용하였다. 분석결과에 따르면, 야간시간대는 건물이 밀집되어있는 단독주거지역이 상업지역이나 공공시설지역보다 열섬강도가 높았고, 이것은 에너지소비에 의한 인공열 방출이 열섬형성에 많은 영향을 미치기 때문으로 판단된다. 또한 이러한 점 때문에 공업지역에서는 건물은 가동시간에 따라 온도차이가 매우 크게 나타났다. 한편, 도시녹지지역과 하천지역은 도시열섬을 완화하는 냉각효과가 있는 것으로 확인되었으며, 열섬강도가 높은 지역에 녹지 및 수변공간의 조성으로 열섬강도를 낮출 필요가 있을 것으로 판단된다. 이상과 같은 결과는 야간시간대의 도시열섬을 완화하는데 있어 개발계획 수립시 효율적인 공간활용을 위해 기초자료로 이용될 것으로 사료된다.

• 토지주택연구
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• 제5권4호
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• pp.291-296
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• 2014

공동주택은 기밀성능 향상에 의해 수증기의 배출이 어려워 졌다. 본 연구에서는 최근에 건설된 소형 공동주택의 실내 온습도의 조건에 대해 현장조사를 수행하여 결로방지 설계 시 필요한 실내 온습도기준을 제시하고자 한다. 조사지역으로는 대전과 성남 지역 3개 공동주택을 대상으로 하였으며, 1월부터 3월 동절기를 대상으로 측정하였다. 실내 온도는 $20{\sim}24^{\circ}C$, 상대습도는 40~60%이며, 조성된 습도는 외부의 영향보다는 주민의 다양한 특성에 의해 발생되었다. 주간(6:00~22:00)과 야간(22:00~6:00)을 비교하면, 야간에는 온도는 낮고 절대습도는 높아 결로발생 가능성이 높을 것으로 판단되었다. 누적 상대빈도와 절대습도를 사용하여 소형 공동주택의 설계 기준(온도, 상대습도)을 설정할 수 있다.

• Journal of Biosystems Engineering
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• 제25권5호
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• pp.379-384
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• 2000

In order to use the natural thermal energy as much as possible for greenhouse heating, the air-air heat pump system involved PCM(phase change material) latent heat storage system was composed, and three types of greenhouse heating system(greenhouse system, greenhouse-PCM latent heat storage system, greenhouse-PCM latent heat storage-heat pump system) were recomposed from the greenhouse heating units to analyze the heating characteristics. The results could be concluded as follows; 1) In the greenhouse heated by the heat pump under the solar radiation of 406.39W/$m^2$, the maximum PCM temperature in the latent heat storage system was 24$^{\circ}C$ and the accumulated thermal energy stored in PCM mass of 816kg during the daytime was 100,320kJ. In the greenhouse without heat pump under the maximum solar radiation of 452.83W/$m^2$, the maximum PCM temperature in the latent heat storage system was 22$^{\circ}C$ and the accumulated thermal energy stored during the daytime was 52.250kJ. 2) In the greenhouse-PCM system without heat pump the heat stored in soil layers from the surface to 30cm of the soil depth was 450㎉/$m^2$. 3) In all of the greenhouse heating systems, the difference between the air temperature in greenhouse and the ambient temperature was about 20~23$^{\circ}C$ in the daytime. In the greenhouse without heat pump and PCM latent heat storage system the difference between the ambient temperature and the air temperature in the greenhouse was about 6~7$^{\circ}C$ in the nighttime, in the greenhouse with only PCM latent heat storage system the temperature difference about 7~13$^{\circ}C$ in the nighttime and in the greenhouse with the heat pump and PCM latent heat storage system about 9~14$^{\circ}C$ in the nighttime.

• 대기
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• 제23권4호
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• pp.471-483
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• 2013

Nighttime sea fog detection from satellite is very hard due to limitation in using visible channels. Currently, most widely used method for the detection is the Dual Channel Difference (DCD) method based on Brightness Temperature Difference between 3.7 and 11 ${\mu}m$ channel (BTD). However, this method have difficulty in distinguishing between fog and low cloud, and sometimes misjudges middle/high cloud as well as clear scene as fog. Using CALIPSO Lidar Profile measurements, we have analyzed the intrinsic problems in detecting nighttime sea fog from various satellite remote sensing algorithms and suggested the direction for the improvement of the algorithm. From the comparison with CALIPSO measurements for May-July in 2011, the DCD method excessively overestimates foggy pixels (2542 pixels). Among them, only 524 pixel are real foggy pixels, but 331 pixels and 1687 pixels are clear and other type of clouds, respectively. The 514 of real foggy pixels accounts for 70% of 749 foggy pixels identified by CALIPSO. Our proposed new algorithm detects foggy pixels by comparing the difference between cloud top temperature and underneath sea surface temperature from assimilated data along with the DCD method. We have used two types of cloud top temperature, which obtained from 11 ${\mu}m$ brightness temperature (B_S1) and operational COMS algorithm (B_S2). The detected foggy 1794 pixels from B_S1 and 1490 pixel from B_S2 are significantly reduced the overestimation detected by the DCD method. However, 477 and 446 pixels have been found to be real foggy pixels, 329 and 264 pixels be clear, and 989 and 780 pixels be other type of clouds, detected by B_S1 and B_S2 respectively. The analysis of the operational COMS fog detection algorithm reveals that the cloud screening process was strictly enforced, which resulted in underestimation of foggy pixel. The 538 of total detected foggy pixels obtain only 187 of real foggy pixels, but 61 of clear pixels and 290 of other type clouds. Our analysis suggests that there is no winner for nighttime sea fog detection algorithms, but loser because real foggy pixels are less than 30% among the foggy pixels declared by all algorithms. This overwhelming evidence reveals that current nighttime sea fog algorithms have provided a lot of misjudged information, which are mostly originated from difficulty in distinguishing between clear and cloudy scene as well as fog and other type clouds. Therefore, in-depth researches are urgently required to reduce the enormous error in nighttime sea fog detection from satellite.

• 천문학논총
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• 제15권spc2호
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• pp.37-44
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• 2000

Two different types of plasma probes have been developed and are currently in operation on board the KOMPSAT-l. One is the cylindrical Langmuir Probe (LP) that measures the electron density and temperature from its current-voltage characteristics in thermal plasmas, and the other is the Electron Temperature Sensor (ETS) which directly gives the information of the ambient electron temperatures. These plasma probes provide the electron properties of the local nighttime ionosphere at the KOMPSAT-l altitudes. In this paper we briefly describe the probes and the initial results obtained from these probes since the beginning of their normal operation in April, 2000.

• 한국환경과학회지
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• 제19권1호
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• pp.81-87
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• 2010

Cool island intensity urban green space was investigated based in Dalsung Park, that is one of the largest parks in Daegu. Cool island intensity(CII), which is defined as the temperature difference between the green space and its surrounding built-up areas, shows time variations. A through-year measurement(2008-2009) of ground level air temperature revealed seasonal variation and relationship to the atmospheric condition of CII. The temperature variation in the park and the reference downtown Daegu was as same order as CII. The noontime CII is larger in summer than that in winter due to the leaf fall of the park trees. On the other hand, seasonal variation of nighttime CII is not so clear. The nighttime CII was larger under the stable atmosphere.

• 한국태양에너지학회 논문집
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• 제28권5호
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• pp.49-55
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• 2008

The radiant cooling(RC) effects are studied during the winter night. The plate was viewing the nighttime sky. The data were collected at the rooftop of the Engineering building at the Dongguk University in Seoul, Korea. As observed during the summer night, the plate temperature was lower than ambient temperature under the RC favorable conditions. The parameters under study are the wind velocity, cloud index, and visibility for given system size and surface condition. The results follow the same tendency with these parameters as observed from the previous study for the summer night. As long as the wind velocity is less than around 2 m/s, the radiant cooling was observed with the system under study. In some cases, the radiant cooling temperature differences (RCTD) are higher than those for the summer night. The larger the RCTD as the wind velocity decreases and as the sky becomes clear.

• 한국대기환경학회지
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• 제24권1호
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• pp.83-90
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• 2008

In order to clarify the urbanization intensity of Daegu Metropolitan and its characteristics, comparative study on the variation of the cooling rate of two different sites was carried out using observation data for 40 years by Korea Meteorological Adminstration. Daegu Metropolitan and Chupungnyung represent well urbanized and rural areas, respectively. In comparison with Chupungnyung, yearly mean temperature at Daegu Metropolitan increases rapidly and especially the differences of minimum temperature increasing rate during 40 years becomes greater. These differences of regional warming are caused by the different urbanization intensity between two sites. And the impact of anthropogenic heat due to urbanization should be stronger in nighttime than in daytime. Sensible heat advection by regional wind during 6 hours from 18 LST contributes to atmospheric cooling. For this reason wind speed is in proportion to cooling rate of atmosphere. However, wind after 24 LST induces the warm air advection and makes decrease the cooling rate in urban area. Although the cooling rates between Daegu Metropolitan and Chupungnyung are some different, the variation tendencies of cooling rate of two site are almost same. Therefore atmospheric cooling rate in nighttime tends to be associated with the intensity of wind speed.

• 한국습지학회지
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• 제21권spc호
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• pp.123-133
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• 2019

본 연구는 2018년에 발생한 폭염 및 한파 발생 기간을 대상으로 습지의 지면온도 완화효과를 평가하기 위해 위성관측 지표면 온도(Land Surface Temperature, LST)와 지상 관측 기온 자료를 활용해 토지 이용별 특성 분석을 실시하였다. 폭염 기간에는 폭염주의보 발령 기준인 최고기온 33℃ 이상인 지역, 한파 기간은 한파주의보 발령 기준인 최저기온 -12℃ 이하의 지역을 대상으로 하였다. 위성 자료로는 Terra/Aqua Moderate Resolution Imaging Spectroradiometer (MODIS)의 Daytime, Nighttime LST 자료, 지상 관측 기온 자료로는 전국 86개소의 종관기상관측장비(Automated Surface Observing System, ASOS) 지점에 대한 최고 및 최저 자료를 수집하여 데이터베이스를 구축하였다. 분석 결과, 한파 기간을 대상으로 하였을 때 산림의 지면온도의 평균이 -12.7℃로 가장 높았으며, 그 뒤로 밭과 습지가 각각 -12.9℃와 -13.0℃로 나타나 평균이 가장 낮은 도시의 -14.4℃에 비해 1.4℃ 더 높았다. 폭염 기간에도 도시지역의 평균이 34.6℃로 가장 높았고 습지는 33.0℃로 도시지역과 - 1.6℃의 차이를 보여 습지의 지면온도 완화효과를 확인하였다. 습지는 기간에 따라 차이는 있으나 지면온도의 완화 기능을 발휘하였고, 원격탐사 영상을 이용한 확인이 가능하였다.

• 한국환경생태학회지
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• 제32권4호
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• pp.373-380
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• 2018

도마뱀부치(Gekko japonicus) 성체와 유체의 주야간에 있어 서로 다른 은신처에 대한 선호 및 경쟁 양상을 알아보기 위하여 실내 사육장에서 성체 9개체(암컷 3, 수컷 6), 유체 4개체를 47일간 사육하면서 연구를 수행하였다. 실험결과, 사육장 내에 설치된 은신처 내부의 온도와 내부에서 발견된 도마뱀부치의 체온은 높은 양의 상관을 보였으며, 야간에 은신처 내부보다 외부에서 더 많은 성체와 유체가 관찰되었다. 성체와 유체 모두 특정 은신처에 대한 선호를 보였는데, 특별히 성체는 주간에 온도가 높은 은신처를 더 높은 비율로 선호하였다. 유체가 가장 선호한 은신처는 주야간에 동일한 은신처였다. 최대비율로 이용한 특정 은신처의 이용률은 성체의 경우 주야 간 차이가 유의한 반면, 유체는 차이가 없었다. 체온의 경우 성체와 유생 모두 야간에 은신처 외부에서 발견된 개체가 내부에서 발견된 개체들보다 더 높았다. 성체와 유생 사이의 체온 비교결과, 주간에 성체의 체온이 유체보다 높았으나, 야간에는 차이가 없었다. 이러한 결과는 도마뱀부치가 야행성으로 나은 온도조건을 가진 은신처를 선호하고 성체와 유체 간에는 은신처 이용경쟁이 있음을 보여주며, 더불어 도마뱀부치의 체온과 활동성에 관한 기초정보를 제공해 준다.