• 제목/요약/키워드: temperature anomaly

검색결과 200건 처리시간 0.05초

Nino3.4지역 SST 및 여름강수량의 독립성분분석 (Independent Component Analysis of Nino3.4 Sea Surface Temperature and Summer Seasonal Rainfall)

  • 권현한;문영일
    • 한국수자원학회논문집
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    • 제38권12호
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    • pp.985-994
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    • 2005
  • 수문시계열을 분석하기 위한 방법으로 낮은 차원에서 해석이 가능한 주성분분석 방법의 문제점을 검토하고 이를 보완할 수 있는 독립성분분석의 이론과 특성을 검토하였고 수문기상자료인 Nino지역의 해수면온도에 적용하여 El $\tilde{n}ino$-Southern Oscillation(ENSO) 사상과의 상관성을 평가하였다. 혼합자료를 사용하여 독립성분분석 방법의 주성분 분리 능력을 검토한 결과 독립성분분석이 기존 주성분분석에 비해 통계적으로 우수한 결과를 나타내었다. El $\tilde{n}ino$의 감시구역인 Nino+3.4지역의 $5^{\circ}{\times}5^{\circ}$(위도와 경도)의 총 20개 Global Anomaly SST 격자자료를 대상으로 분석을 실시하여 El $\tilde{n}ino$-Southern Oscillation(ENSO)사상의 발생시기와의 상관관계를 평가하였으며 한 개의 독립성분($86\%$)만으로 SST의 전체적인 거동을 표현할 수 있었으며 주요 ENSO 발생시기와 일치하는 결과를 나타내었다. 또한 국내 주요지점의 여름 강수량을 대상으로 독립성분분석을 적용한 결과 지역적인 특성을 고려하여 비교적 합리적으로 독립성분을 추출할 수 있었으며 IC-1과 IC-2에서 1970년대 이후로 여름강수량의 증가를 확인할 수 있었다.

CFD in Hypersonic Flight

  • 박철
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2009년 춘계학술대회논문집
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    • pp.1-8
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    • 2009
  • This is a short review of how CFD contributed to hypersonic flights in the past 50 years. Two unexpected phenomena that occurred in the entry flights of the Apollo and Space Shuttle made us aware of the impact of the high temperature real-gas effects on hypersonic flights: pitching moment anomaly of up to 4 degrees, and radiation overshoot behind a shock wave. The so-called two-temperature nonequilibrium model was introduced to explain these phenomena. CFD techniques were developed to accommodate the two-temperature model. Presently, CFD can predict trim angle of attack to an accuracy of about 1 degree. A concerted effort was made to numerically reproduce the experimentally measured flow-field over a double-cone. As yet, perfect agreement between the experimental data and computation is not achieved. Scramjet technology development is disappointingly slow. The phenomenon of ablation during planetary entries is not yet predicted satisfactorily. In the future, one expects to see more research carried out on planetary entries and space tourism.

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지열자료 정보 D/B 구축 요소 (Geothermal properties for Database)

  • 김형찬;박정민
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 추계학술대회
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    • pp.28-31
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    • 2006
  • It is require to construct geothermal database to develop geothermal energy as renewable energy policy. It must be consist of geologic data, borehole data and geophysical data for geothermal database. In aspect of geology, there are included the distribution of geology, structural geology, geological time, rock name, density of rock, porosity, thermal diffusivity, specific capacity and thermal conductivity In order to calculate the heat general ion, it is needed to analysis the radioactivity elements as U, Th and K of rock. In aspect of borehole data, there are included temperature of depth, surface temperature and geothermal gradient And also there is geotherrnornetry using chemical components of groundwater as Na Ca, K and $SiO_2$. In aspect of geophysical data, there are some thematic map as booger gravity anomaly data and magnetic survey data and etc. In addition, it is important to descript the distribution of hot spring and water temperature.

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CLIMATIC TRENDS OF SOME PARAMETERS OF THE SOUTHERN OCEAN DERIVED FROM REMOTE SENSING DATA

  • Lebedev, S.A.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.1023-1026
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    • 2006
  • As it was shown recently, climate changes in Antarctica resulted in interannual trends of some climatic parameters like sea level pressure, surface air temperature, ice thickness and others. These tendencies have effect on the Southern Ocean meteorological and hydrological regime. The following remote sensing data: AVHRR MCSST data, satellite altimetry data (merged data of mission ERS-2, TOPEX/Poseidon, Jason-1, ENVISAT, GFO-1) are used to analyse the interannual and/or climatic tendency of sea surface temperature (SST) and sea level anomaly (SLA). According to the obtained results, SST has negative trend $-0.02{\pm}0.003^{\circ}C/yr$ for 24-yr record (1982-2005) and SLA has positive trend $0.01{\pm}0.005$ cm/yr for 24-yr record (1982-2005) and $0.24{\pm}0.026$ cm/yr for 12-yr record (1993-2005). However in some areas (for example, Pacific-Antarctic Ridge) SST and SLA tendencies are stronger $-0.065{\pm}0.007^{\circ}C/yr$ and $-0.21{\pm}0.05$ cm/yr, respectively.

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2012 엘니뇨의 발달 분석 (On the Development of 2012 El Niño)

  • 안순일;최정
    • 대기
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    • 제22권4호
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    • pp.465-472
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    • 2012
  • Using various observed data, we examined the evolution of tropical Pacific sea surface temperature (SST) during 2011-2012, with focusing on the development of 2012 El Ni$\tilde{n}$o. It is observed that a La Ni$\tilde{n}$a event during 2011 was followed by a moderate El Ni$\tilde{n}$o during 2012 summer. The 2012 summer El Ni$\tilde{n}$o initiated near the west coast of South America on February 2012, and continued to expand westward till August. Given this evolutionary pattern, the 2012 summer El Ni$\tilde{n}$o can be categorized as 'Eastern Pacific (EP) El Ni$\tilde{n}$o' because Ni$\tilde{n}$o-3 index is greater than Ni$\tilde{n}$o-4 index, and it may be the first well-defined EP El Ni$\tilde{n}$o since 2001. On February 2012, this event was initiated mainly by the local air-sea interaction, and at the same time the ocean heat content was accumulated over the tropical western Pacific due to the easterly wind anomaly over the tropical western Pacific. Then, the accumulated heat content slowly propagates to the tropical eastern Pacific, which attributes to maintain El Ni$\tilde{n}$o state during 2012 summer. After August, the positive SST anomaly over the equatorial eastern Pacific decays possibly due to the exhausted heat content and the weakening of air-sea interaction, but the weak positive SST anomaly over the central Pacific remains till now (2012 November).

실리콘 패킹 기술을 이용한 방수 콘센트의 개발 (Development of Waterproof Electric Outlet using Silicon Packing Technology)

  • 최충석;김창성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 춘계학술대회 논문집 전기설비전문위원
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    • pp.85-87
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    • 2008
  • In this paper, we manufactured waterproof outlet that use silicon packing know-how. Developed outlet is waterproof packing on pins of the plug insertion hole and electric wire insertion hole. Therefore, outlet body internal furnace water can prevent that is flowed in. Temperature anomaly can use in back large outer wall, restaurant exposed easily to moisture, bathroom, laundry, a laboratory and science room, auditorium, etc. That is estimate that contribute on courtesy call of electricity calamity.

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Empirical Mode Decomposition (EMD) and Nonstationary Oscillation Resampling (NSOR): II. Applications in Hydrology and Climate sciences

  • Lee, Tae-Sam;Ouarda, TahaB.M.J.;im, Byung-Soo
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2011년도 학술발표회
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    • pp.91-91
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    • 2011
  • In the present study, the proposed EMD and NSOR models has been applied in hydrology and climate sciences. Here, we present those applications as the following: (1) to extend future scenarios of Global Surface Temperature Anomaly including long-term oscillation component; (2) to extend the future evolution of the Eastern Canada winter precipitation; (3) to apply EMD in detecting climate change.

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환원 BaTiO$_3$반도체의 이상전도현상 (Conduction Anomaly in Oxygen Deficient Single Crystals of BaTiO$_3$)

  • 성영권;장봉호;신동열
    • 전기의세계
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    • 제22권3호
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    • pp.7-12
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    • 1973
  • Single crystals of BaTiO$_{3}$ which were grown by Remeika's method were on reducing them is hydrogen atmosphere at about 400-1000.deg. C for about 30hrs. They became light brown and seems to have an effect on their properties by oxygen deffects especially at a Curie temperature of 122.deg. C exhibitted abnormal reducting resistivity. These semiconducting tendency were studied experimentally by observing through several electrical properties and were discussed on the basis of exchange semiconductor mechanism.

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Influence of Seasonal Forcing on Habitat Use by Bottlenose Dolphins Tursiops truncatus in the Northern Adriatic Sea

  • Bearzi, Giovanni;Azzellino, Arianna;Politi, Elena;Costa, Marina;Bastianini, Mauro
    • Ocean Science Journal
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    • 제43권4호
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    • pp.175-182
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    • 2008
  • Bottlenose dolphins are the only cetaceans regularly observed in the northern Adriatic Sea, but they survive at low densities and are exposed to significant threats. This study investigates some of the factors that influence habitat use by the animals in a largely homogeneous environment by combining dolphin data with hydrological and physiographical variables sampled from oceanographic ships. Surveys were conducted year-round between 2003 and 2006, totalling 3,397 km of effort. Habitat modelling based on a binary stepwise logistic regression analysis predicted between 81% and 93% of the cells where animals were present. Seven environmental covariates were important predictors: oxygen saturation, water temperature, density anomaly, gradient of density anomaly, turbidity, distance from the nearest coast and bottom depth. The model selected consistent predictors in spring and summer. However, the relationship (inverse or direct) between each predictor and dolphin presence varied among seasons, and different predictors were selected in fall. This suggests that dolphin distribution changed depending on seasonal forcing. As the study area is relatively uniform in terms of bottom topography, habitat use by the animals seems to depend on complex interactions among hydrological variables, caused primarily by seasonal change and likely to determine shifts in prey distribution.

시계열 수질 분석에 의한 제주도의 해저용출수 탐사 및 검증 (Exploration and Verification of Submarine Groundwater Discharge on Jeju Island by Remotely Sensed Based Water Quality Analysis)

  • 백승균;박맹언
    • 자원환경지질
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    • 제38권4호
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    • pp.395-409
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    • 2005
  • 새로운 수자원으로서의 가능성이 대두되는 제주도 연안의 해저에 존재하는 용출수의 위치를 파악하기 위해 원격탐사 자료와 GIS 기법을 적용하였다. 4월, 8월, 12월에 촬영된 Landsat TM자료를 이용하여 해수면 온도, 투명도, 클로로필-a 분포 특성을 분석함으로써 제주도 연안 해저의 용출수와 관련된 이상대를 파악하였다. 또한 지질도, 수계분포도, 분석구 분포 밀도도, 선구조 분포 밀도도, 지하수위도 등의 주제도를 이용한 퍼지기반 공간통합분석을 실시하여 제주도 해안에 주로 분포하는 용천수의 분포 특징을 분석한 결과 Landsat TM 자료 분석 결과와 밀접한 상관관계를 나타내었다.