• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2011년도 학술발표회
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• pp.350-353
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• 2011

전 세계적으로 기후변화로 인한 자연재해가 빈번하게 발생함에 따라 수자원 분야에서 또한 환경의 변화에 대한 정확한 예측이 더욱 요구되고 있다. 국내에서도 이를 위하여 다양한 방법을 통하여 연구가 이루어지고 있으나 본 연구에서 사용된 Common Land Model (CLM)은 국내에서의 실질적인 적용이 아직 부족하다. 이 모형은 Soil-Vegetation-Atmosphere Transfer 모형 중 대표적 모델로 Land Surface Model (LSM), Biosphere-Atmosphere Transfer Scheme (BATS), Chinese Academy of Sciences Institute of Atmospheric Physics LSM의 세 모형이 결합되어 발전하였다. CLM의 강제입력자료로는 위성, 지면모형 등을 기반으로 만들어진 자료를 제공하는 Korea Land Data Assimilation Systme (KLDAS; 한반도지표자료동화체계)의 격자화 된 자료를 사용하여 모형에 강제시켰다. KLDAS는 기존의 Land Data Assimilation System (LDAS)에서 발전한 형태로 동아시아 지역을 대상으로 자료를 제공하고 있으며, 본 연구에서는 이 자료를 사용하여 국내 전반에 걸쳐 격자에 대한 수문 기상학적 인자를 산출하였다.

• Ocean Science Journal
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• 제43권3호
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• pp.147-152
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• 2008

The seasonal variability of sonic layer depth (SLD) in the central Arabian Sea (CAS) (0 to $25^{\circ}N$ and $62-66^{\circ}E$) was studied using the temperature and salinity (T/S) profiles from Argo floats for the years 2002-2006. The atmospheric forcing responsible for the observed changes was explored using the meteorological data from NCEP/NCAR and Quickscat winds. SLD was obtained from sound velocity profiles computed from T/S data. Net heat flux and wind forcing regulated SLD in the CAS. Up-welling and down-welling (Ekman dynamics) associated with the Findlater Jet controlled SLD during the summer monsoon. While in winter monsoon, cooling and convective mixing regulated SLD in the study region. Weak winds, high insolation and positive net heat flux lead to the formation of thin, warm and stratified sonic layer during pre and post summer monsoon periods, respectively.

• 천문학회보
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• 제36권2호
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• pp.151.1-151.1
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• 2011

We present the Exposure Time Calculator of IGRINS. The noises of IGRINS can be calculated from the combination of Telluric background emission and absorptions, the emission and transmission of the telescope and instrument optics, and the dark noise and the read noise of the infrared arrays. For the atmospheric transmissions, we apply the simulated spectra depending on the Precipitable Water Vapor (PWV) values. The user needs to input the expected target magnitude, the weather conditions, and the desired exposure time. The output would be the expected signal-to-noise for each spectral resolution element.

• 천문학회보
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• 제38권1호
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• pp.26-26
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• 2013

The high Antarctic plateau is the driest and coldest environment on the surface of the Earth and offers superlative conditions for the conduct of a wide range of astronomical observations, from optical to millimetre wavebands. This includes, especially, the infrared - where the sky background is greatly reduced from temperate sites - and the sub-millimetre / THz bands - where new or cleaner atmospheric windows can be viewed through. Astronomical observations have now been conducted from five locations on the Antarctic plateau - the South Pole, Domes A, C and F, and Ridge A. Ambitious plans for the construction of observatories there have been announced. An IAU Symposium on "Astrophysics from Antarctica" featured as part of last year's IAU General Assembly in Beijing. This talk will provide an overview of astronomy in Antarctica, describing the special conditions that make some forms of observation particularly favourable there, and discuss the development of observatories on the Antarctic plateau and the plans for their future development.

• 천문학회지
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• 제34권2호
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• pp.81-97
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• 2001

Since the first proposal by Paczynski, great efforts to detect Galactic dark matter by detecting light variations of stars located in the Magellanic Clouds and Galactic bulge caused by gravitational microlensing have been and are being carried out and more than 1,000 events have been successfully detected. In this paper, we review the progress in the theoretical and experimental progresses in microlensing. We begin with basics of microlensing and summarize the results obtained from the last 8 year observations along with the implications of the results. We also discuss the usefulness of microlensing in other fields of astronomy such as the stellar atmosphere, Galactic binary systems, and extra-solar planets. We finally discuss the problems of the current experiments and the new types of observations that can overcome these problems.

• Journal of the Optical Society of Korea
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• 제16권3호
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• pp.191-195
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• 2012

Among the atmospheric effect of laser propagation, the variations of the radiation transmittance by water aerosol evaporation have quantitatively been investigated. When the aerosol was exposed by a 1.07 ${\mu}m$ cw fiber laser, the increased amount of the transmittance variation was a maximum of 19.1% and the volume concentration variation of aerosol was observed as an increasing of laser intensity. Also, significant irregularity of refractive index was not found in the heated area during the continuous laser heating.

• Transactions on Electrical and Electronic Materials
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• 제2권4호
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• pp.7-10
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• 2001

A new possibility of our atmospheric cold plasma torch has been examined on the surface treatment of an air-exposed vulcanized rubber compound. The plasma treatment effect was evaluated by the bondability with another rubber compound using a polyurethane adhesive. The adhesion property was improved by the treatment with plasma containing oxygen radicals. The oxygen radical generation from the plasma was verified and its efficiency was found to be dependent on the cathode material.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1278-1280
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• 2003

Striping is a main factor for imaging spectroradiometer data, which is obtained by multi-sensor scanning on spacecraft. The reason causing stripes and the development of striping removal methods are simply described in this paper, particularly, the principle of Matching Empirical Distribution Functions is introduced in detail. By using this method, some experiments are done to destripe imaging spectrometer data of SZ-3. The result shows that the method of Matching Empirical Distribution Functions is available for destirping Imaging spectroradiometer data of SZ-3, and the quality of image is improved obviously. This will help to process the future similar instruments data.

• Journal of the Optical Society of Korea
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• 제14권3호
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• pp.215-220
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• 2010

Aerosol observation with Raman LIDAR in NIES (National Institute for Environmental Studies, Japan) LIDAR network was conducted from 17 April to 12 June 2008 over Beijing, China. The aerosol optical properties derived from Raman LIDAR were compared with the retrieved data from sun photometer and sky radiometer observations in the Aerosol Robotic Network (AERONET). The comparison provided the complete knowledge of aerosol optical and physical properties in Beijing, especially in pollution and Asian dust events. The averaged aerosol optical depth (AOD) at 675 nm was 0.81 and the Angstrom exponent between 440 nm and 675 nm was 0.99 during experiment. The LIDAR derived AOD at 532 nm in the planetary boundary layer (PBL) was 0.48, which implied that half of the total AOD was contributed by the aerosol in PBL. The corresponding averaged LIDAR ratio and total depolarization ratio (TDR) were 48.5sr and 8.1%. The negative correlation between LIDAR ratio and TDR indicated the LIDAR ratio decreased with aerosol size because of the high TDR associated with nonspherical and large aerosols. The typical volume size distribution of the aerosol clearly demonstrated that the coarse mode radius located near 3 ${\mu}m$ in dust case, a bi-mode with fine particle centered at 0.2 ${\mu}m$ and coarse particle at 2 ${\mu}m$ was the characteristic size distribution in the pollution and clean cases. The different size distributions of aerosol resulted in its different optical properties. The retrieved LIDAR ratio and TDR were 41.1sr and 19.5% for a dust event, 53.8sr and 6.6% for a pollution event as well as 57.3sr and 7.2% for a clean event. In conjunction with the observed surface wind field near the LIDAR site, most of the pollution aerosols were produced locally or transported from the southeast of Beijing, whereas the dust aerosols associated with the clean air mass were transported by the northwesterly or southwesterly winds.

• 한국지구과학회지
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• 제40권3호
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• pp.203-211
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• 2019

대기 대순환을 결정하는 주요 인자로는 남북방향 온도 경도와, 지구 자전으로 인한 코리올리 힘이 있다. 남북방향 온도 경도에 따른 경압성 차이로 인한 대기 대순환의 변화는 지금까지 많이 연구되어 왔으나, 자전속도에 따른 대기 대순환의 반응은 크게 연구되어 오지 않았다. 때문에 본 연구에서는 현 지구보다 느리거나 빠른 자전속도 범위를 모두 포괄하여 이에 따른 해들리 순환과 제트의 변화를 확인하였다. 이 연구에서 우리는 지구의 자전속도가 빨라질수록 해들리 순환 경계와 제트의 위치가 적도에 가까워지고, 제트와 해들리 순환의 세기가 약해진다는 것을 발견하였다. 해들리 순환 경계와 제트의 위치는 자전속도가 매우 빠르거나 느린 경우를 제외하면 준선형적인 관계를 가졌다. 특히, 해들리 순환 경계는 자전속도가 현재보다 1/8에서 8배의 자전속도 범위에서 자전속도보다 그 제곱근에 더 잘 반비례하는 경향성을 보였다. 단, 이러한 자전속도에 따른 변화는 해들리 순환 세기와 제트의 세기에 대해서는 뚜렷하지 않았다. 이는 대기 대순환의 위치 구조 변화는 지구 자전속도와 관련이 큰 반면, 세기의 변화는 자전속도로 설명되지 않음을 의미한다.