• 대한전자공학회논문지SD
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• 제39권12호
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• pp.1008-1015
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• 2002

분극처리 없이 제작한 lanthanum-modified lead titanate (PLT) 박막의 초전특성에 대한 변조 주파수 의존성을 dynamic method를 이용하여 조사하였다. La이 10mo1% 첨가된 Pb/sub l-x/La/sub x/Ti/sub l-x/4/O₃ (h=0.1) (PLT(10)) 박막을 Pt/TiO/sub x//SiO₂/Si 기판위에 acetate 계 precursor 을 이용한 sol-gel 법으로 제작하였다. 제작된 PLT(10) 박막은 비교적 우수한 유전특성을 보였다. 초전계수 (p) 는 주파수 의존성이 없이 6.6×10/sup -9/ C/㎠·K 을 나타내었다. 이를 이용하여 구한 전압감도와 비검출능을 위한 재료평가지수는 각각 1.03×10/sup -11/ C·㎝/J 과 1.46×10/sup -9/C·㎝/J 로 나타났다. 제작된 PLT(10) 박막 초전형 적외선 센서는 주파수 8Hz 에서 5.15v/w 의 전압감도 (Rv)를 가지며, 잡음등가전력 (NEP) 과 비검출능 (D/sup */) 은 동일한 주파수 100Hz 에서 각각 9.93×10/sup -8/W/Hz/sup 1/2/와 1.81×10/sup 6/cm·Hz/sup 1/2//W 의 최소값과 최대값을 나타내었다. 이와 같은 특성들은 PLT(10) 박막이 초전형 적외선 센서의 감지물질로 매우 적합함을 나타낸 것이다.

• 천문학논총
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• 제27권4호
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• pp.151-152
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• 2012

We present the method of star/galaxy separation based on the support vector machines (SVM) in the data from the AKARI North Ecliptic Pole (NEP) Deep survey collected through nine AKARI / IRC bands from 2 to $24{\mu}m$, with a classification accuracy of 93 %.

• 전기저널
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• 통권353호
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• pp.65-71
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• 2006

금년도 에너지 · 자원기술개발에 3,671억원을 투입 키로/ 전자제품 살 땐 '전기흡혈귀' 잡는 마크 확인하세요(대기전력)/ 한전, 실시간 낙뢰정보 서비스 제공/ 한수원, 일본 R&I社 신용등급 1등급 상향 A+획득/ 중부발전, Blue JB 설비운영/관리분야 워크샵 실시/ 동서발전, 울돌목 조류발전건설 MOU체결/ 서부발전, 혁신리더 워크샵, "3가지 혁신습관(안)" 채택/ 남부발전-중소기업 함께하는 ESCO사업/ 현대중공업, 2006 하노버 박람회 참가/ 두산중공업, 생산현장 직원 등반대회/ 포스코, 포스코파워 지분 전량 인수/ LS전선 가스히트펌프(GHP), 국내 첫 NEP인증 획득/ LS산전. RoHS 대응 친환경경영 선언

• 천문학회보
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• 제33권2호
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• pp.40.1-40.1
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• 2008

• 천문학회보
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• 제33권2호
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• pp.35.2-35.2
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• 2008

• 천문학회보
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• 제34권1호
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• pp.192-192
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• 2009

• 천문학회보
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• 제40권1호
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• pp.55.1-55.1
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• 2015

The first Korean infrared space telescope MIRIS (Milti-purpose InfraRed Imaging System) was successfully launched in November 2013, as the main payload of Korean STSAT-3 (Science and Technology Satellite-3). After initial on-orbit operation for verification, the observations have been made with MIRIS for the fluctuation of Cosmic Infrared Background and the Galactic Plane survey. For the study of near-infrared background, MIRIS completed the survey of large areas (> $10^{\circ}{\times}10^{\circ}$ around the pole regions: the north ecliptic pole (NEP), the north and south Galactic poles (NGP, SGP). We are also continuously and frequently monitoring the NEP region for the instrumental calibration and the zodiacal light study. One the other hand, the Paschen-${\alpha}$ Galactic plane survey has been carried out using two narrow-band filters (at $1.88{\mu}m$ and $1.84+1.92{\mu}m$) of MIRIS. This survey is planning to cover the whole Galactic plane with the latitude of ${\pm}3^{\circ}$, and the longitude regions of $+280^{\circ}<l<360^{\circ}$ and $0^{\circ}<l<+210^{\circ}$ have been completed (~ 80%) by February 2015. The data are still under the stage of reduction and analysis, and we present some preliminary results.

• 천문학논총
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• 제32권1호
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• pp.257-261
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• 2017

We built a $8{\mu}m$ selected sample of galaxies in the NEP-AKARI field by defining 4 redshift bins with the four AKARI bands at 11, 15, 18 and 24 microns (0.15 < z < 0.49, 0.75 < z < 1.34, 1.34 < z < 1.7 and 1.7 < z < 2.05). Our sample contains 4079 sources, 599 are securely detected with Herschel/PACS. Also adding ultraviolet (UV) data from GALEX, we fit the spectral energy distributions using the physically motivated code CIGALE to extract the star formation rate, stellar mass, dust attenuation and the AGN contribution to the total infrared luminosity ($L_{IR}$). We discuss the impact of the adopted attenuation curve and that of the wavelength coverage to estimate these physical parameters. We focus on galaxies with a luminosity close the characteristic $L^*_{IR}$ in the different redshift bins to study the evolution with redshift of the dust attenuation in these galaxies.

• 천문학논총
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• 제32권1호
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• pp.235-237
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• 2017

The AKARI NEP Deep Field Survey is an international multiwavelength survey over $0.4deg^2$ of the sky. This is the deepest survey made by the InfraRed Camera (IRC) of the infrared astronomical satellite AKARI with 9 filters continuously covering the $2-25{\mu}m$ range, including three filters in the Spitzer gap between the IRAC and MIPS coverages. This enabled us to make sensitive MIR detection of AGN candidates at z~ 1, based on hot dust emission in the AGN torus. It is also efficient in detecting highly obscured Compton-thick AGN population. In this article, we report the first results of X-ray observations on this field. The field was covered by 15 overlapping Chandra ACIS-I observations with a total exposure of ~300 ks, detecting ${\approx}450$ X-ray sources. We utilize rest-frame stacking analysis of the MIR AGN candidates that are not detected individually. Our preliminary analysis shows a marginal detection of the rest-frame stacked Fe $k{\alpha}$ line from our strong Compton-thick candidates.

• 천문학논총
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• 제32권1호
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• pp.239-244
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• 2017

How does the presence of an AGN influence the total SFR estimates of galaxies and change their distribution with respect to the Galaxy Main Sequence? To contribute to solving this question, we study a sample of 1133 sources detected in the North Ecliptic Pole field (NEP) by AKARI and Herschel. We create a multi-wavelength dataset for these galaxies and we fit their multi-wavelength Spectral Energy Distribution (SED) using the whole spectral regime (from 0.1 to $500{\mu}m$). We perform the fit using three procedures: LePhare and two optimised codes for identifying AGN tracers from the SED analysis. In this work we present an overview of the comparison between the estimates of the Infrared bolometric luminosities (between 8 and $1000{\mu}m$) and the AGN fractions obtained exploiting these different procedures. In particular, by estimating the AGN contribution in four different wavelength ranges ($5-40{\mu}m$, $10-20{\mu}m$, $20-40{\mu}m$ and $8-1000{\mu}m$) we show how the presence of an AGN affects the PAH emission by suppressing the ratio $\frac{L_{8{\mu}m}}{L_{4.5{\mu}m}}$ as a function of the considered wavelength range.