• Journal of Microbiology and Biotechnology
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• 제7권5호
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• pp.318-322
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• 1997

In order to isolate a microorganism having preferential degradation of D-carnitine from DL-carnitine, a bacterium assimilating D-carnitine as a sole carbon and energy source was isolated from soil by enrichment culture and partially identified as Enterobacter sp. Also, a mutant having lessened L-carnitine decomposition rates was selected with nitrosoguanidine mutagenesis, which led to decrease the specific activities of carnitine dehydrogenase (7.6-fold) and ${\beta}$-hydroxybutyrate dehydrogenase (9.5-fold) as compared to the wild strain. Meanwhile, optimal culture conditions for optical resolution of DL-carnitine were investigated. Under optimal conditions, 3.53 g/l L-carnitine was obtained from 20 g/l DL-carnitine, which corresponded to 35.3% L-carnitine yield and 97.9% optical purity.

• Journal of Astronomy and Space Sciences
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• 제18권1호
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• pp.21-26
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• 2001

As part of a long-term program for polar upper atmospheric studies, temperatures and intensities of the OH(3-1) bands were derived from spectrometric observations of airglow emissions over King Sejong station($62.22^{circ}S,\;301.25^{circ}E$). These measurements were made with a Michelson interferometer to cover wavelength regions between 1000nm and 2000 nm. A spectral analysis was performed to individual nights of data to acquire information on the waves in the upper mesosphere/lower thermosphere. It is assumed that the measured fluctuations in the intensity and temperature of the OH (3-1) airglow were caused by gravity waves propagating through the emission layer. Correlation of intensity and temperature variation revealed oscillations with periods ranging from 2 to 9 hours. We also calculated Krassovsky’s parameter and compared with published values.

• 한국정보처리학회논문지
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• 제4권4호
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• pp.973-981
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• 1997

본 논문은 이동 호스트에게 멀티캐스트 서비스 재공시 고려되어야할 주요 특징 및 문제점을 확인하고, 이러한 문제점들을 해결하기 위한 방안을 제시하였다. 이동 하는 호스트의 상태를 포함하는 그룹 뷰의 아이디어를 소개하고, 그룹 뷰를 이용하여 멀티캐스트 전달의 의미를 확보하는데 초점을 맞춘다. 본 논문의 결과는 이동 호스트 를 위한 멀티캐스트 서비스의 기초를 제공할 것이다.

• Journal of information and communication convergence engineering
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• 제9권6호
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• pp.647-651
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• 2011

In this letter, non-regenerative Amplify-and-Forward (AF) relay systems based on half and full duplex schemes are investigated and their performance is analyzed and compared in terms of outage probability. Although the AF relay systems have been widely investigated in many previous literatures, most of them adopted a half duplex scheme due to hardware limitation and mathematical tractability. To the best of our knowledge, this letter is the first study to investigate the performance of the full duplex AF relay system considering practical hardware limitations. In full duplex AF relay systems, it is important to secure the isolation between transmit and receive antennas. Our numerical and simulation results show that there exists a threshold point of the isolation gain that the full duplex relay system outperforms the half duplex relay system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.79-79
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• 2009

Samples of Ta-doped in $In_2O_3-ZnO-SnO_2$(IZTO) with a doping level up to 4wt% were sintered at $1600^{\circ}C$ in $O_2$. The crystal phase of the samples was identified by an X-ray diffraction experiment. apparent density and porosity with sintered temperature from $1500^{\circ}C$ to $1640^{\circ}C$ are mesured by archimedes method. For each sample, the specific resistivity was determined. samples of sintered at $1600^{\circ}C$ had the highest density and lowest porousity and The Ta 0.25-wt%-doped IZTO ceramics had the lowest resistivity.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.133-138
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• 2008

This study proposes a novel method for in-service evaluation of force in an external prestressing 7-wire tendon which is employed for retrofitting bridge superstructure. For this propose, a smart strand 7.0m long whose king wire is replaced by a steel tube and the FBG sensor, is developed. Performance of the strand is demonstrated through loading-unloading tests for a RC T-shaped beam 6.4m long. Finally, a couple of test results are presented to discuss effect of temperature change in the FBG sensor.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1999년도 학술발표대회 논문집 제18권 2호
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• pp.127-130
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• 1999

본 논문에서는 수신된 CW 신호로부터 Morse 코드를 자동 인식하는 알고리듬을 제안하였다. 전체 알고리듬은 수신된 CW 신호로부터 잡음 및 간섭신호 성분을 제거하고 신호의 존재유무를 판정하는 부분, 신호 길이의 변화를 극복하여 Morse 코드의 요소(Long, Short, Null set)로부터 코드로 판독하는 부분으로 구성되었다. 제안된 알고리듬은 CW 신호의 주파수, 위상 및 길이 정보가 필요 없으며, 모의 실험 결과, SNR -15dB, $20\%$의 신호 길이 변화 환경에서도 $100\%$의 해석률을 나타내었다.

• KDI Journal of Economic Policy
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• 제39권3호
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• pp.43-62
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• 2017

This paper proposes an integrated risk-management framework that includes 1) measuring the risk of credit portfolios, 2) implementing a (macro) stress test, and 3) setting risk limits using the estimated systematic latent factor specific to capture the housing market cycle. To this end, we extract information from a set of real-estate market variables based on the FAVAR methodology proposed by Bernanke, Boivin and Eliasz (2005). Then, we show the method by which the estimated systematic factor is applied to risk management in the housing market in an integrated manner within the Vasicek one-factor credit model. The proposed methodology is well fitted to analyze the risk of slow-moving and low-defaultable forms of capital, such as alternative investments.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2006년도 추계 종합학술대회 논문집
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• pp.111-114
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• 2006

본 논문은 GeometriX장비를 통해 획득된 데이터를 가공하여 Morphable 모델을 생성한다. 기존의 MPI[3]에서 만들어진 Morphable 모델은 Cyberware[10]장비로 획득된 가공하지 않은(raw) 데이터를 사용하였기 때문에 픽셀의 수와 정점의 수가 같아 원칙적으로 대용량의 데이터를 가진다. 이를 해결하고자 모델 생성에 참조되는 픽셀의 수가 정점의 수 보다 월등히 많은 모델을 사용한 Morphable 모델을 생성한다.

• 한국컴퓨터정보학회논문지
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• 제9권3호
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• pp.103-107
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• 2004

소프트웨어의 재사용은 생산성 향상, 소프트웨어의 신뢰성 향상, 소프트웨어 개발기간 단축, 개발비용 절감, 시스템 관련 정보 공유 등의 장점을 지닌다. 수직적 재사용은 하나의 영역 또는 응용 분야에서만 재사용함으로서, 높은 이해성으로 인해 재상용의 신뢰성을 높일 수 있는 방법이다. 소프트웨어 시스템을 개발할 때 사용되는 정보들을 재사용을 목적으로 분류하여, 결과물들을 추상화하는 상향식 방법을 이용하여 단순 코드의 재사용에서 벗어나 비형식적인 자료들을 포함해 모든 정보를 사용 가능하게 할 수 있다.