• IEIE Transactions on Smart Processing and Computing
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• 제3권1호
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• pp.35-39
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• 2014

This paper proposes a Modified Minimum Mean Square Error (M-MMSE) estimator for an Orthogonal Frequency Division Multiplexing (OFDM) System over fast fading Rayleigh channel. The proposed M-MMSE estimator considered the effects of the efficient placement of pilots based on the channel energy distribution. The pilot symbols were placed in a non-linear manner according to the density of the channel energy. Comparative analysis of the MMSE estimator for a comb-type pilot arrangement and M-MMSE estimator for the proposed pilot insertion scheme revealed significant performance improvement of the M-MMSE estimator over the MMSE estimator.

• 천문학회보
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• 제37권1호
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• pp.35.1-35.1
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• 2012

Determining the virial factor of the broad-line region (BLR) gas is crucial in calibrating AGN black hole mass estimators, since the measured line-of-sight velocity needs to be converted into the representative velocity of the BLR gas. The unknown virial factor has been empirically calibrated based on the $M_{BH}-{\sigma}_*$ relation of non-AGN galaxies, but the claimed values are different by a factor of 2 in recent studies. We investigate the origin of the difference by measuring the $M_{BH}-{\sigma}_*$ relation using the most updated nearby galaxy sample, and explore the dependence of the virial factor on the various fitting methods. We find that the discrepancy is mostly caused by the sample bias while the difference stemming from various regression methods is marginal. Based on the best-determined virial factor, we present the updated $M_{BH}-{\sigma}_*$ relation of local active galaxies.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2419-2422
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• 2014

The syntheses and crystal structures of a three-dimensional (3D) coordination network $[Zn_4(2-mBIM)_5-(C_2H_6NCOO)(HCOO)({\mu}-OH)]{\cdot}DMF$ ($1{\cdot}$DMF; 2-mBIM = 2-methylbenzimidazolate) and a two-dimensional (2D) layer $[Zn_2(2-mBIM)_3(HCOO)(H_2O)]{\cdot}DMF$ ($2{\cdot}DMF$) are reported. Different structures were produced depending on the ratio of reactants. Structurally, 1 illustrates the formation of a unique framework based on a 2-mBIM bridge with the side group on an imidazole ring, while 2 possesses a honeycomb layer built up purely from imidazolates. For gas sorption, $CO_2$ is adsorbed on the activated phase of 1 but $N_2$ is not taken up.

• 한국동물학회지
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• 제13권3호
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• pp.94-100
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• 1970

C. challengeri는 아한대수의 전형적인 부유성 단각류로써 서부 북태평양의 $40^\\circ N$ 이북인 오야시오 수역에 널리 분포하고 있으며, 이 해역의 중심층 동물플랭크톤 생물량의 큰 비중을 차지하고있다. 본종은 구로시오 본류 이남이나 북태평양 중앙 수역에 가끔 출형하여 그 분포의 남한이 재검토 되었다. 한편 본종의 수직분포와 생물량의 일주수직이동도 아울러 검토되어 35-1,750m 사이에 서시하고, 주간에는 180-280m, 야간에는 35-100m에서 성군을 함을 알았다. 또 250m의 범위를 수직이동하여 상부의 유기물질을 심부로 수송하는 역할을 맡고 있다. 본종의 남하는 아한대중층수의 이동에 따르며 분포의 환경요인은 수온 $(10^\\circ C 이하)$과 염분도 (30 \ulcorner 이하)임을 밝혔다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1691-1696
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• 2010

Jeong-Ji overbridge is designed to be 9.3km long, the longest for a high speed railway bridge ever constructed in Korea. This bridge is constituted of three types of structure. Standard type bridge is 35m PSC Box bridge which will be constructed by Precast Span Method. To cross the Cheonan Nonsan Expressway, 80m three-span steel arch bridge is designed to avoid rail expansion joint. Finally, Extradosed bridge is planned for high speed railway bridge for the first time in Korea based on originative and advanced design techniques. It is expected that this will contribute to the development of national technology for long-span high speed railway bridges.

• BMB Reports
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• 제35권3호
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• pp.302-305
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• 2002

Kinetic and thermodynamic studies have been made on the effect of the inosine product on the activity of adenosine deaminase in a 50 mM sodium phosphate buffer, pH 7.5, at $27^{\circ}C$ using UV spectrophotometry and isothermal titration calorimetry (ITC). A competitive inhibition was observed for inosine as a product of the enzymatic reaction. A graphical-fitting method was used for determination of the binding constant and enthalpy of inhibitor binding by using isothermal titration microcalorimetry data. The dissociation-binding constant is equal to $140\;{\mu}M$ by the microcalorimetry method, which agrees well with the value of $143\;{\mu}M$ for the inhibition constant that was obtained from the spectroscopy method.

• 한국측량학회지
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• 제9권2호
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• pp.67-72
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• 1991

OSU89B를 이용하여 한반도 일원의 지오이드와 수직선편차에 대하여 연구하였다. 한반도 일원에서 지오이드는 GRS1980 지구타원체에 비해 +3m~+35m 범위의 변화를 나타내며, 전반적으로 서에서 동으로 높아져 감이 특징적이다. 수직선편차는 $\xi$가 -8.9"~8.0", $\eta$가 -13.1"~9.0"의 범위의 변화를 보이며 전반적으로 서편경향이 특징적이다.며 전반적으로 서편경향이 특징적이다.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1995년도 추계학술발표회 초록집
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• pp.15-18
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• 1995

내경 0.1 m, 높이 0.9 m 의 draft tube 를 갖는 직경 0.3 m, 높이 2.7 m 인 내부순환유동층가스화 반응기에서 생성가스분리대를 설치하여 가스화구역에서 생성된 생성가스를 분리하여 중열량가스를 얻었다. 석탄공급량 4.3 - 8.6 kg/hr, $O_2$/C 의 비 0.25 - 0.35, $H_2O$/C 의 비 0.75 - 1.35 의 조업변수 변화조건에서 생성가스의 조성과 발열량이 측정되었다. 반응 온도가 증가함에따라 H$_2$ 와 CO가 증가하고 $CO_2$ 와 $N_2$는 감소하여 생성가스 발열량이 10 - 11.5 MJ/㎥ 으로 증가하였다.

• 한국산업정보학회논문지
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• 제19권2호
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• pp.31-36
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• 2014

본 논문에서는 나노기술을 적용한 압저항형 온 습도복합센서를 개발하여 특성을 평가 분석 하였다. 온도 변화에 대한 출력 감도는 $20{\sim}80^{\circ}C$에 이르는 측정구간에서 약 0.75mV/$1^{\circ}C$의 출력 값을 보였다. 습도 변화에 대한 감도는 약 1.35mV/10%(RH)의 결과를 나타내었다. 이와 같은 결과에 의하여 본 논문에서 개발한 센서는 일반적인 생활 주거 환경에 적용이 가능함을 시사해 준다.

• Mycobiology
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• 제35권3호
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• pp.124-128
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• 2007

Ganoderma resinaceum tolerated sodium chloride salt stress within a range of 0 mM till 300 mM. It responded to salt stress with fluctuation in proline formation at different NaCl concentrations. However, the mycelial dry weight, total protein contents and exopolysaccharides did not changed considerably. Increasing sodium chloride concentration led to morphological alteration in fungal mycelia with disappearance of fungal cell wall, plasmolysis, and vacuolation as indicated with electron microscopic examination of the fungal growth.