• 천문학회보
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• 제46권2호
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• pp.69.2-69.2
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• 2021

We present the discovery of rare active galactic nuclei (AGNs) in nearby (z<0.05) compact elliptical galaxies (cEs) located in isolated environments. Using spectroscopic data from the Sloan Digital Sky Survey (SDSS) Data Release 12, four AGNs were identified based on the optical emission-line diagnostic diagram. SDSS optical spectra of AGNs show the presence of distinct narrow-line emissions. Utilizing the black hole (BH) mass-stellar velocity dispersion scaling relation and the correlation between the narrow L([OIII])/L(Hβ) line ratio and the width of the broad Hα emission line, we estimated the BH masses of the cEs to be in the range of 7×10⁵-8×10⁷ solar mass. The observed surface brightness profiles of the cEs were fitted with a double Sérsic function using the Dark Energy Camera Legacy Survey r-band imaging data. Assuming the inner component as the bulge, the K-band bulge luminosity was also estimated from the corresponding Two Micron All Sky Survey images. We found that our cEs follow the observed BH mass-stellar velocity dispersion and BH mass-bulge luminosity scaling relations, albeit there was a large uncertainty in the derived BH mass of one cE. In view of the observational properties of BHs and those of the stellar populations of cEs, we discuss the proposition that cEs in isolated environments are bona fide low-mass early-type galaxies (i.e., a nature origin).

• 한국항해학회지
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• 제22권4호
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• pp.59-67
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• 1998

A quick and automatic detection with no harm to the goods is very important task for improving quality control, process control and labour reduction. In real fields of industry, defect detection is mostly accomplished by skillful workers. A narrow band eliminating spatial filter having characteristics of removing the specified spatial frequency is developed by the author, and it is proved that the filter has an excellent ability for on-line and real time detection of surface defect. By the way,. this spatial filter shows a ripple phenominum in filtering characteristics. So, it is necessary to remove the ripple component for the improvement of filter gain, moreover efficiency of defect detection. The spatial filtering method has a remarkable feature which means that it is able to set up weighting function for its own sake, and which can to obtain the best signal relating to the purpose of the measurement. Hence, having an eye on such feature, theoretical analysis is carried out at first for optimal design of narrow band eliminating spatial filter, and secondly, on the basis of above results spatial filter is manufactured, and finally advanced effectiveness of spatial filter is evaluated experimentally.

• 대한전자공학회논문지TC
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• 제41권12호
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• pp.109-114
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• 2004

본 논문에서는 마이크로스트림 전송선로에 주기적으로 삽입된 좁은 폭의 슬릿을 이용하여 물리적 길이가 소형화되는 전송 선로인 ILCTL(inductively loaded compact transmission line)을 소개하였다. 주기적으로 부가된 좁은 폭의 슬릿은 마이크로스 트립 전송선로에서 직렬로 부가되는 인덕턴스 역할을 함으로써 전송선로의 길이를 소형화한다. 그리고 이러한 ILCTL을 이용하여 소형화된 rat-race 결합기를 구현하였다. 1.8 GHz에서 구현된 소형화된 rat-race 결합기는 일반적인 구조에 비해 60％의 크기를 가짐을 MoM(methods of moments)기반의 full-wave analysis를 이용한 2.5D EM(electromagnetic) solver의 계산과 제작 및 측정을 통하여 확인하였다.

• 대한기계학회논문집A
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• 제23권7호
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• pp.1231-1237
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• 1999

Applying the conjugate contact condition, contact lines of a cylindrical worm gear has been calculated. The characteristics of tooth contact were analyzed and the pitting resistance were also assessed. It has been verified that: i) the length of contact is shortest on the 1st tooth of the front region, ii) the contact region is more narrow in the recess side than in the access side, iii) the contact region is more narrow in worm than in worm wheel. Hence, the pitting resistance is weakest in the recess side of the 1st contacting worm tooth.

• 한국광학회:학술대회논문집
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• 한국광학회 1991년도 제6회 파동 및 레이저 학술발표회 Prodeedings of 6th Conference on Waves and Lasers
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• pp.45-45
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• 1991

We describe a simple method for obtaining a narrow dip with subnatural linewidth in Doppler-free laser spectroscopy. The method is based on detecting the absolute magnitude, ｜Re[$\chi$NL($\omega$-$\omega$o)]｜, of the dispersive component (real part) of the nonlinear susceptibility induced by the pump beam, and the line shape recorded therefore exhibits a fully resolved technique and a dual phase lock-in amplifier, we have demonstrated the dip as narrow as 3 MHz in the laser-induced birefringence spectrum of the Na D1 line (natural linewidth 10 MHz). Possible spectroscopic applications are considered.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 춘계종합학술대회
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• pp.227-229
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• 2002

본 논문에서는 마이크로스트립 라인 전압제어 가변 대역통과필터를 제안한다. 박막 강유전체의 상대 유전율은 인가 전압에 따라 변하는 특성을 이용하였고, Au/BSTO/MgO/Au 구조로 설계하였다. 커플링 수가 3개인 공진기를 연결하여 공진기 사이의 간격을 잘 조절한 격과, 중심 주파수 16 GHz 에서 1.9 GHz의 튜닝 범위, 800MHz 내의 좁은 대역폭, 3dB 이내의 작은 삽입손실을 갖는 필터를 설계할 수 있었다.

• 천문학회보
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• 제37권2호
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• pp.97.1-97.1
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• 2012

NIR Emission lines from singly-ionized Iron, in particular [Fe II] $1.64{\mu}m$, are good tracer of dense atomic gas in star-forming regions, around evolved stars, and in supernova remnants. We are imaging about 180 square degrees along the Galactic Plane ($6^{\circ}$ < l < $65^{\circ}$;$-1.5^{\circ}$ < b < $+1.5^{\circ}$) with the narrow band filter centered on the [Fe II] $1.64{\mu}m$ line using WFCAM at UKIRT. The observations will complement the UWISH2 survey, which have imaged the same area with the narrow band filter centered on the molecular hydrogen 1-0 S(1) emission line at $2.12{\mu}m$, and probe a dynamically active component of ISM. We present the goals and preliminary results of our survey.

• 복식문화연구
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• 제12권4호
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• pp.511-528
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• 2004

The purpose of this study was to find out comparison of preference style and wearing style of pants and skirt by body perception and satisfaction. This research was done by a survey method. Descriptive Statistics, Coefficients MANOVA, Two-Way ANOVA, t-test and Duncan＇s test were used for data analysis. The results of this study are as follows. 1) The subjects with the highest dissatisfaction about waist girth prefer high waist pants. The subjects with longer waist wear high waist pants. The subjects with wider hips wear narrow down pants. The subjects with the thickest thighs prefer narrow pants but wear narrow down pants. The subjects with the highest dissatisfaction about calf thickness prefer narrow pants but wear wide pants. The subjects with the highest satisfaction about leg length prefer and wear calf length pants. The subjects with the thinnest calves prefer and wear tight pants. 2) The subjects with the thickest thighs prefer straight skirt but wear narrow down skirt. The subjects with the highest dissatisfaction about thigh thickness wear A-line skirt.

• 한국정보통신학회논문지
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• 제5권5호
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• pp.1011-1016
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• 2001

본 논문에서는 교차 및 결합 선로를 갖는 마이크로스트립 개방루프 공진기를 이용한 협대역 대역통과 여파기를 설계.제작하였다. 이 여파기는 크기가 작고 경량이며, 협대역 타원함수 대역통과 특성과 같은 우수한 특성을 가지고 있다. 여파기는 두 개의 동일한 마이크로스트립 개방루프 공진기와 교차 및 결합선로로 구성되어 있다. 개방루프 공진기를 사용함으로서 여파기 크기는 링 공진기와 비교하여 50% 정도가 축소된다. 교차선로는 억제대역에서 두 개의 노치를 제공하므로, 통과대역에서 예리한 선택도를 가진다. 중심주파수 2.455GHz로 설계된 마이크로스트립 대역통과 여파기는 1.22%의 대역폭을 가지며, 이는 무선LAN의 응용에 매우 적합하다. 여파기는 포토 에칭법으로 제작하였다 제작된 대역통과 여파기는 2.458GHz대에서 0.85%의 대역폭을 가지며 크기는 $2.6cm\times1cm$이다.

• 한국통신학회논문지
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• 제13권1호
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• pp.94-105
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• 1988

본 논문은 ISDN 실현 초기 단계에서 제공되는 서비스중 협대역 정보신호(2B+D)를 기존의 가입자 선로를 이용하여 전송할 때 요구되는 국내가입자 선로의 특성을 조사하고 전송선로 특성 조건에 관한 국제적인 동향과 비교, 분석하였으며, 그 결과를 분석하여 이를 모델링하였다. 그 결과 U-트랜시버의 수신레벨이 -31dBm 이하일 경우에는 기준품질 확보가 불가능하며, 측정회선의 3.6%는 협대역 ISDN 전송로로는 사용할 수 없는 것으로 나타났다. 선로잡음의 주요 형태는 임펄스성 잡음과 근단누화가 주류를 이루고 있으며 착오발생 형태는 버스트 모드보다 순간성이 강한 것으로 확인되었다. BER 측정결과 측정회선중 70% 이상의 회선이 품질기준을 충족시키는 구간은 2.5km이내로 관측되었다.