• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.131-132
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• 2009

본 논고는 2008년 전라북도에서 발주된 계곡${\sim}$신덕간 국지도 확 포장공사 대안설계중 하천 병행 및 횡단교량의 친환경 건설계획을 위한 최적 교량형식 및 시공공법 선정의 설계과정을 소개하는데 그 목적을 두었다.

• 설비공학논문집
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• 제20권3호
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• pp.197-204
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• 2008

DMFC(Direct Methanol Fuel Cell) is one of promising candidates for power sources of small mobile IT devices like notebook, cell phone, and so on. Efficient operation of fuel cell system is very important for long-sustained power supply because of limited fuel tank size. It is necessary to investigate operation characteristics of fuel cell stack for optimal control of DMFC system. The generated voltage was modeled according to various operating condition; methanol concentration, stack temperature, and load current. It is inevitable for methanol solution at anode to cross over to cathode through MEA(membrane electrode assembly), which reduces the system efficiency and increases fuel consumption. In this study, optimal operation conditions are proposed by analyzing stack performance model, cross-over phenomenon, and system efficiency.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2006년도 에너지.가스.기후변화학회 연합춘계학술대회 및 특별심포지움
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• pp.198-201
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• 2006

• 대한수학회지
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• 제49권1호
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• pp.139-151
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• 2012

In the previous paper, we gave a characterization of backward shift invariant subspaces of the Hardy space over the bidisk on which [${S_z}^n$, $S_w^*$] = 0 for a positive integer n ${\geq}$ 2. In this case, it holds that ${S_z}^n=cI$ for some $c{\in}\mathbb{C}$. In this paper, it is proved that if [$S_{\varphi}$, $S_w^*$] = 0 and ${\varphi}{\in}H^{\infty}({\Gamma}_z)$, then $S_{\varphi}=cI$ for some $c{\in}\mathbb{C}$.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2001년도 춘계학술발표논문집 (하)
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• pp.1029-1032
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• 2001

자기구성 특징지도(Self-Organizing feature Map : SOM) 및 $L^*$ 등의 자가 학습 신경망의 알고리즘들은 학습 결과 중에 바람직하지 못한 뒤틀림 현상(cross-over)을 생성하게 되므로 재학습으로 인한 전반적인 학습 시간의 지연을 초래한다. 이 논문에서는 비교적 학습 속도가 빠른 $L^*$의 점증적 학습 구조를 기본으로 하여 뒤틀림 현상 방지를 목적으로 초기 학습 단계에서 학습 가중치들의 노드들을 재조정하는 개선된 알고리즘을 제안한다. 이러한 알고리즘의 실험 결과는 모두 정상적인 학습 결과를 보이고 학습의 시행 착오적인 재실행이 없으므로 전반적인 학습 속도는 기존의 알고리즘보다 빠르게 됨을 보인다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.360-360
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• 2000

In this paper, a new criterion f9r determining the sampling rate of digital conroller is proposed. This paper will introduce a method fur determining the appropriate sampling rate of digital controller which can be substituted with the given analog controller, using phase margin and gain cross over frequency, not rising time or bandwidth of the closed-loop system. This method also guarantees performance of the system. Without exact modeling functions of the plant, abstracting those functions, this paper can achieve stability and aimed performance of the system, and this paper proved it with proper modeling functions.

• Journal of Pharmaceutical Investigation
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• 제24권2호
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• pp.49-55
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• 1994

Bioequivalence test of commercially available rifampicin capsules was performed. Sixteen volunteers were divided into 2 groups and the reference and test drug were given orally (450 mg) by cross-over design. Statistical evaluation of AUC, $C_{max}\;and\;T_{max}$ involved an analysis of variance (ANOVA). The differences of mean value in AUC, $C_{max}\;and\;T_{max}$ between the reference and test drug were within 20% with reference drug. ANOVA showed no significant differences for ‘between group’, ‘drug’ and ‘period’, but not for ‘between subjects’. The power of test $(1-{\beta})\;of\;AUC\;and\;$C_{max}$ was larger than 0.8 and the confidence of bioavailability was $within\;{\pm}20%$. From these results, it was concluded that the two preparations were bioequivalent for AUC and $C_{max}$, but was not for $T_{max}$.

• 한국ITS학회 논문지
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• 제11권4호
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• pp.70-79
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• 2012

FMCW 레이더에서 주파수 램프 신호를 발생시키기 위하여 필요한 타입-3 PLL의 설계 가이드를 제시하였다. 그러기 위해서 개루프 전달함수의 크로스오버 주파수를 1 Hz로 정규화 한 조건에서 Pspice 시뮬레이션을 통하여 폐루프 특성을 비교하였다. 결론적으로 타입-3 PLL의 1) 위상여유는 45도로 하고, 2) 두 개의 영점은 같도록 하며, 3) PLL 차수를 높이기 위한 극점은 개루프 전달함수의 크로스오버 주파수보다 10배 정도 크게 할 것을 권한다.

• 한국산업보건학회지
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• 제15권1호
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• pp.36-44
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• 2005

A push pull hood system is frequently applied to control contaminants evaporated from an open surface tank in recent years. Efficiency of push pull hood system is affected by various parameters, such as cross draft, vessel shapes, size of tanks surface, liquid temperature, and so on. Among these, velocity of cross draft might be one of the most influencing factor for determining the ventilation efficiency. To take account of the effect of cross draft velocities over 0.38m/s, a flow adjustment of ${\pm}$20% should be considered into the push and +20% into the pull flow system Although there are many studies about the efficiency evaluation of push pull hood system based on CFDs(Computational Fluid Dynamics) and experiments, there have been no reports regarding the influence of velocities and direction of cross-draft on push-pull hood efficiency. This study was conducted to investigate the influence of cross draft direction and velocities on the capture efficiency of the push-pull ventilation system. Smoke visualization method was used along with mock-up of push-pull hood systems to verify the ventilation efficiency by experiments. When the cross-draft blew from the same origins of the push flows, the efficiency of the system was in it's high value, but it was decreased significantly when the cross-draft came from the opposite side of push flows Moreover, the efficiency of the system dramatically decreased when the cross-draft of open surface tank was faster than 0.4m/s.

• Journal of the Optical Society of Korea
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• 제11권4호
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• pp.158-161
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• 2007

We proposed a novel linearization technique for a DFB LD in the RoF link. The proposed scheme is based on the cross gain modulation(XGM) effect of a reflective semiconductor optical amplifier(RSOA) with light injection. We experimentally demonstrated and evaluated the enhanced CIR performance using the proposed linearization scheme.