• 한국지능시스템학회논문지
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• 제23권1호
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• pp.72-79
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• 2013

본 논문에서는 태양광 발전시스템의 최대전력점을 추종하기 위해, 개방회로전압과 가까운 첫 번째 지역극대전력점(local peak power point)의 전압 및 전류값이 특정한 범위 내에 있을 경우, 첫 번째 지역극대점이 전역극대전력점(global peak power point)인지 판단할 수 있도록 패턴을 분석하였다. 직-병렬 어레이로 연결된 태양전지 모듈에 부분그늘문제(partial shading problem)가 발생할 경우 다수의 지역극대전력점이 관찰될 수 있어, 전역극대전력점을 찾는데 어려움이 있다. 부분선형 태양전지 모델을 이용한 태블로 해석(Tableau analysis)으로 태양전지 어레이 회로의 V-I 특성을 시뮬레이션하여 지역극대전력점과 전역극대전력점을 확인하고, 그에 해당하는 전압 및 전류 값과 V-I 특성곡선의 패턴을 분석하였다. 분석된 패턴을 통해 특정한 영역을 설정하여 첫 번째 지역극대전력점이 전역극대전력점 인지 판단하여 발전하는 경우, 첫 번째 지역극대전력점으로만 발전했을 때에 비해 효율이 향상되었다.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1993년도 학술논문발표회 논문집 제12권 1호
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• pp.259-262
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• 1993

In this paper, a new pitch beginning point detection method by extracting the G-peak, is proposed. By the speech production model, the area of the first peak on a pitch interval of speech signals is emphasized. By using the above characteristics, this method have more advantages than the others for pitch beginning point detection. The defective decision caused by an impulsive noise is minimized and the pre-filtering is not necessary for this method, because the integration of signals takes place in the process.

• 한국광학회지
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• 제9권4호
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• pp.245-250
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• 1998

본 논문에서는 백색광주사간섭무늬의 정점검출을 위한 새로운 디지털처리 알고리즘을 제안한다. 본 알고리즘은 백색광주사간섭무늬의 가시도함수를 이차의 다항식으로 가정하고, 측정된 광강도 값들을 최소자승법을 이용하여 직접적으로 곡선맞춤하여 가시도함수의 정점의 위치를 검출한다. 기존의 정점검출 알고리즘들과 비교하여, 본 이차다항식맞춤 알고리즘은 가시도함수의 추출을 위한 별도의 연산이 요구되지 않아 3N+29의 작은 곱셈 계산량만으로 연산을 완료 할 수 있다. 또한 최소자승법을 사용함으로써 간섭무늬가 갖는 외부 교란을 효과적으로 억제하여 안정된 해를 제공하는 장점을 갖는다.

• 설비공학논문집
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• 제15권9호
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• pp.768-778
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• 2003

Numerical analysis has been carried out to investigate laminar convective heat transfer in a tube for supercritical water near the thermodynamic critical point. Fluid flow and heat transfer are strongly coupled due to large variations of thermodynamic and transport properties such as density, specific heat, viscosity, and thermal conductivity near the critical point. Heat transfer characteristics in the developing region of the tube show transition behavior between liquid-like and gas-like phases with a peak in heat transfer coefficient distribution near the pseudocritical point. The peak of the heat transfer coefficient depends on pressure and wall heat flux rather than inlet temperature and Reynolds number, Results of the modeling provide convective heat transfer characteristics including velocity vectors, temperature, and the properties as well as the heat transfer coefficient. The effect of proximity to the critical point is considered and a heat transfer correlation is suggested for the peak of Nusselt number in the tube.

• East Asian mathematical journal
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• 제24권1호
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• pp.7-10
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• 2008

We prove a localization theorem of Azukawa pseudometric at a local plurisubharmonic peak point of a domain in the complex Euclidean space.

• 한국안광학회지
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• 제6권1호
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• pp.101-105
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• 2001

UV 차단 렌즈 UV solution을 이용한 dip method로 제작하여 광 투과율과 광 반사율을 측정하였다. 광 투과율의 half point 파장 및 edge 파장이 dip 시간의 존성인 exponetial decay형식에 잘 적용되었다. $$W=W_0+A_1{e}{x}{p}[-(x-x_1)/t_1]$$ 광 투과율의 half point 파장은 358 nm 에서 408 nm로 이용하였고, edge 파장은 340 nm에서 398 nm로 이동하였다. 광 반사율 주 peak 380 nm는 dip 시간이 클수록 세기는 작아지고 장파장 쪽으로 이동하였으며, dip 시간 10분에서 UV solution의 성분 peak가 나타나기 시작하였다.

• International Journal of Air-Conditioning and Refrigeration
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• 제13권4호
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• pp.206-216
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• 2005

Numerical analysis has been carried out to investigate laminar convective heat transfer at zero gravity in a tube for supercritical water near the thermodynamic critical point. Fluid flow and heat transfer are strongly coupled due to large variation of thermodynamic and transport properties such as density, specific heat, viscosity, and thermal conductivity near the critical point. Heat transfer characteristics in the developing region of the tube show transition behavior between liquid-like and gas-like phases with a peak in heat transfer coefficient distribution near the pseudo critical point. The peak of the heat transfer coefficient depends on pressure and wall heat flux rather than inlet temperature and Reynolds number. Results of the modeling provide convective heat transfer characteristics including velocity vectors, temperature, and the properties as well as the heat transfer coefficient. The effect of proximity on the critical point is considered and a heat transfer correlation is suggested for the peak of Nusselt number in the tube.

• Imaging Science in Dentistry
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• 제47권1호
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• pp.1-9
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• 2017

Purpose: This retrospective study aimed to evaluate the nasopharyngeal and oropharyngeal dimensions of individuals with skeletal class II, division 1 and division 2 patterns during the pre-peak, peak, and post-peak growth periods for comparison with a skeletal class I control group. Materials and Methods: Totally 124 lateral cephalograms (47 for skeletal class I; 45 for skeletal class II, division 1; and 32 for skeletal class II, division 2) in pre-peak, peak, and post-peak growth periods were selected from the department archives. Thirteen landmarks, 4 angular and 4 linear measurements, and 4 proportional calculations were obtained. The ANOVA and Duncan test were applied to compare the differences among the study groups during the growth periods. Results: Statistically significant differences were found between the skeletal class II, division 2 group and other groups for the gonion-gnathion/sella-nasion angle. The sella-nasion-B-point angle was different among the groups, while the A-point-nasion-B-point angle was significantly different for all 3 groups. The nasopharyngeal airway space showed a statistically significant difference among the groups throughout the growth periods. The interaction among the growth periods and study groups was statistically significant regarding the upper oropharyngeal airway space measurement. The lower oropharyngeal airway space measurement showed a statistically significant difference among the groups, with the smallest dimension observed in the skeletal class II, division 2 group. Conclusion: The naso-oropharyngeal airway dimensions showed a statistically significant difference among the class II, division 1; class II, division 2; and class I groups during different growth periods.

• 대한수학회지
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• 제33권2호
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• pp.399-411
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• 1996

Let $\Omega$ be a smoothly bounded pseudoconvex domain in $C^n$ and let $A(\Omega)$ denote the functions holomorphic on $\Omega$ and continuous on $\bar{\Omega}$. A point $p \in b\Omega$ is a peak point if there is a function $f \in A(\Omega)$ such that $f(p) = 1, and $\mid$f(z)$\mid$ < 1 for z \in \bar{\Omega} - {p}$.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제11권2호
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• pp.149-154
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• 2004

We show that the Choquet boundary of the tensor product of two real function algebras is the product of their Choquet boundaries.