• 대기
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• 제15권4호
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• pp.229-239
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• 2005

The effect of inversion layer on the land and sea breeze near the Gangneung city was investigated. The land and sea breeze occurrence days were selected, and the height and the intensity of inversion layer were calculated with the upper air observational data of the Sokcho Station. The relationships between the temperature variation near the Gangneung and the inflow time, inland penetration and the inflow depth of the land and sea breeze were also analyzed. And the Gangwon Short-range prediction system was verified with the comparison of surface stream line by the Gangwon short-range prediction system with the AWS wind vector data. It was revealed that the inversion layer tended to block the sea breeze, shorten the inland penetration distance and lower the inflow depth, causing the temperature rise. The comparison and analysis of surface steam line by the Gangwon short-range prediction system and the AWS wind vector showed that the system quite well simulated the sea breeze, thus the system could be well utilized in the prediction of land and sea breeze.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.320-323
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• 2006

Temperature inversion may cause air pollution problems because air pollutants cannot be dissipated through vertical motion of the atmosphere and are accumulated near the surface. The air quality is worsen gradually if an inversion event lasts for a long time. An inversion event is defined as consecutive temperature profiles with occurrence of the temperature inversion condition. In this paper, temperature inversion events over three major cities on Taiwan are analyzed. They are measured by ground-based microwave radiometers installed in Taipei, Taichung, and Kaohsiung from 2002 to 2004 by the Environment Protection Administration (EPA) of Taiwan. Characteristics of temperature inversion events at the three cities are extracted using different classification methods.

• 한국환경과학회지
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• 제5권6호
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• pp.713-718
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• 1996

We identified two characteristic turbulent flow cases, weakening and strengthening, which appear at the downwind side. Observations were made two times, Dec. 2-3. 1995 and Feb. 13-14. 1996 at Pusan National University site located downwind side of Kumjeong mountain. Meteorological observation system, tethersonde, was adopted to present observation. In the case of the west wind which blows perpendicular to Sanghak mountain located westward from the site, the wind speed highly increased in exponential with height. Therefore, the low level wind speed was so weak just like Taylor(1988)'s review. While the wind speed was intensified at 200-400m layer when the northwest wind blows from the continental Siberian high. We suppose 기 is because of the strong vertical convergence of flow between the surface inversion layer and the upper one, and also the horizontal convergence along the saddle and valley between the two mountains, Kumjeong and Sanghak-because of Bernoulli's effect. The inversion layer existed at surface-l00m and 500-600m level and the strong wind existed at about 200-400m layer.

• JSTS:Journal of Semiconductor Technology and Science
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• 제10권2호
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• pp.100-106
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• 2010

The impact of surface quantization on device parameters of a Si metal oxide semiconductor (MOS) capacitor has been analyzed in the present work. Variation of conduction band bending, position of discrete energy states, variation of surface potential, and the variation of inversion carrier concentration at charge centroid have been analyzed for different gate voltages, substrate doping concentrations and oxide thicknesses. Oxide thickness calculated from the experimental C-V data of a MOS capacitor is different from the actual oxide thickness, since such data include the effect of surface quantization. A correction factor has been developed considering the effect of charge centroid in presence of surface quantization at strong inversion and it has been observed that the correction due to surface quantization is crucial for highly doped substrate with thinner gate oxide.

• 해양환경안전학회지
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• 제15권3호
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• pp.165-171
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• 2009

1999년 10월, 12월의 국립수산과학원 정선관측 자료를 이용하여 수온역전 현상이 성층변동에 미치는 영향을 분석하였다. 10월, 12월 모두 수심 25-75m 사이에서 수온역전현상이 빈번하게 발생하며, 12월에는 표층 부근에도 수온역전현상이 나타났다. 고온, 고염분수인 쓰시마난류의 수평 이류가 10월, 12월에 나타나는 수온역전현상의 주원인으로 작용하며, 12월에는 연안역에서 외양역으로 수송되는 차가운 표층수의 영향이 함께 작용한다. 10월에는 북풍이 지속적으로 불지만 남해연안수가 외해역으로 확장하는 현상이 뚜렷하지 않는 반면, 북서풍계열의 풍속이 강해지고 쓰시마난류의 세력이 약해지는 12월에는 남해연안수가 상층부를 통해 외해역으로 확장하면서 수온역전현상을 나타나게 한다. 10월과 12월 모두 수온역전현상이 발생하는 해역을 따라 성층의 변동폭이 크게 나타난다.

• 한국항공운항학회지
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• 제14권4호
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• pp.94-100
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• 2006

The purpose of this case study is to determine the possibility of Numerical Forecasting of sea fog at West Sea in spring time. For practical method of analyzing the data collected from 24th to 26th March 2003, Numerical Weather Prediction model MM5(Mesoscale Model Version 5) and synoptic field study using synoptic chart, upper level chart, and sea surface temperature were employed. The results of synoptic field analysis summarized that sea fog at West sea in spring is intensified by the inflow of the warm flow from west or southwest, low sea surface temperature to increase the temperature difference between air and sea surface, and inversion layer to disturb the disperse. It appears that the possibility of sea fog forecasting by MM5, in view of the result that the MM5 output is similar to the synoptic fields analysis.

• 한국지구과학회지
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• 제21권6호
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• pp.675-682
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• 2000

금강하구 부근의 연약지반에서 획득한 탄성파 자료(25개 shot gather)를 역산하여 2차원 S파 속도구조를 구하였다. 탐사측선위에 위치한 2개 시추홀에서 지질조사를 실시하고 표준관입시험을 실시하였다. 2차원 S파 속도구조는 대상지역의 지층이 두께 1${\sim}$3m의 상부층(S파 속도 200${\sim}$700m/sec), 두께 5${\sim}$8m의 중간 저속도층(S파 속도 100m/sec${\sim}$400m/sec)과 그 아래 S파 속도 1000m/sec 이상의 하부층으로 이루어져 있음을 보인다. 저속도층은 탐사측선의 한쪽 끝에서 다른 쪽 끝으로 가면서 그 두께가 얇아지고, 기반암의 깊이도 얕아진다. S파 속도구조와 지층의 지질, 표준관입시험 값을 검토한 결과, 저속도층은 clay층과 밀접한 관련이 있는 것으로 사료된다. 이에 비해 Standard Penetrarion Test 값은 지층의 성분과는 연관성을 보이지 않고, 깊이에 따라 증가하는 것으로 나타난다. 이 연구는 표면파 역산이 연약지반의 S파 속도구조를 밝히는 데 효과적으로 사용될 수 있음을 보여준다. 또한 표면파 역산 방법은 연약지반에 흔히 존재하는 지표에 가까운 지하수면, 또는 저속도 층으로 인한 굴절파 탐사방법의 한계를 극복할 수 있는 방법을 제공한다.

• 한국환경과학회지
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• 제3권3호
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• pp.217-228
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• 1994

The climatological study of temperature inversion was conducted at the Tsukuba of Japan during the cold half year, the periods of which were both from October 1981 through March 1982 and from October 1982 through March 1983. Meteorological phenomena were observed to appear both from l0m to 200m above the ground and from the surface to 300hPa. The data collected from those phenomena were analyzed in terms of statistics and investigated from a synoptic point of view. The results are as follow. The dispersion of the surface inversion happens right after sunrise through the whole period. The higher the upper layer is, the later that happens. Up to a height of 200m, the wind speed at a height of 25m has the greatest effect on temperature, but on the other hand the wind speed at a height of l0m has the greatest effect on inversion intensity.

• 대한전자공학회논문지SD
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• 제42권3호
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• pp.9-16
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• 2005

[ $Si_{1-x}Ge_x$ ] 위의 Si 반전층에서의 이동도를 반전층에서의 양자현상(버금띠 에너지와 파동함수)과 완화시간어림셈을 고려하여 계산하였다. 반전층에서의 양자현상은 슈뢰딩거 방정식과 포아슨 방정식을 자체 모순없이 계산하여 얻었다 완화시간은 밸리내 산란과 밸리사이 산란을 고려하여 계산하였다. 그 결과 Ge 함량이 증가됨에 따라 이동도가 증가되는 이유는 4-폴드 밸리에 존재하는 전자의 이동도보다 2-폴드 밸리에 존재하는 전자의 이동도가 약 3배 정도 크며 대부분의 전자가 밸리의 분리에 의해 2-폴드 밸리에 존재하기 때문이라는 것을 알 수 있었다. 한편, 포논 산란만을 고려한 이동도를 실험치와 일치시키기 위하여 전체 이동도에는 반전층 계면에서의 산란과 쿨롱 산란을 포함시켰다. 계산된 전계, 온도, 그리고 Ge 함량에 의존하는 이동도는 실험치와 근접하도록 변형포텐셜을 설정하였으며 정확한 결과를 위해서는 Si 에너지띠의 비포물성을 고려해야함을 확인하였다.

• 한국환경과학회지
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• 제21권7호
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• pp.815-824
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• 2012

The purpose of this study was to analyze the meteorological characteristics of wintertime high PM10 concentration episodes in Busan. $PM_{10}$ concentration has been reduced for the past four years and recorded near or exceeded 100 ${\mu}g/m^3$ (national standard of $PM_{10}$). High concentration episodes in Busan were 6 case, $PM_{2.5}/PM_{10}$ ratio was 0.36~0.39(mean 0.55). High $PM_{10}$ concentration occurred during higher air temperature, more solar radiation and sunshine, lower relative humidity, and smaller cloud amount. Synoptically, it also occurred when Busan was in the center or the edge of anticyclone and when sea breeze intruded. An analysis of upper air sounding showed that high $PM_{10}$ concentration occurred when surface inversion layer and upper subsidence inversion layer existed, and when boundary layer depth and vertical mixing coefficient were low. An analysis of backward trajectory of air mass showed that high $PM_{10}$ concentration was largely affected by long range transport considering that it occurs when air mass is intruded from China.