• 전력전자학회:학술대회논문집
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• 전력전자학회 1996년도 창립기념 전력전자학술발표회 논문집
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• pp.85-88
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• 1996

New power factor correction(PFC) technique based on the averaged model of boost converter is proposed. Without measurement of input current, power factor correction scheme derived from the averaged model is presented. With the measurements of input voltage and output voltage, the control signal is generated to make the shape of the line current same as the input voltage. The characteristics of input line current distortion is analyzed by considering the generation of duty cycle.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.164.1-164.1
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• 2011

Previously, many researchers assessed nearshore wave energy in two ways. The first is a simulation with respect to the offshore wave time series to validate the wave buoy data and the wave model results, and the other is to simulate the representative waves of typical seasonal wave conditions. The former requires enormous computational time and effort. The latter yields inspection on the patterns for the spatial and temporal distribution of nearshore wave energy but tends to underestimates the amount of wave energy in the nearshore region owing to the correlation between the significant wave height and wave period. $\ddot{O}$zger et al. (2004) derived the stochastic wave energy formulation by introducing a correction factor explicitly in terms of the covariance of the wave energy and significant wave height. In this study, a correction factor was applied for the assessment of nearshore wave energy obtained by numerical simulation of wave transformation with respect to representative waves.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.271-273
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• 2002

Switching power supply are widely used in many industrial field. Power factor correction(PFC) has become an increasingly necessary feature in new power supply designs. The power factor correction circuit using boost converter used in input of power source is studied in this paper. In a boost power factor correction circuit there are two feedback control loops, which are a current feedback loop and a voltage feedback loop. In this paper, it is analyzed regulation performance of output voltage and compensator to improve of transient response that presented at continuous conduction mode(CCM) of boost PFC circuit. The validity of designed boost PFC circuit is confirmed by simulation and experimental results.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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• pp.443-448
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• 1998

With using artificial neural networks (ANNs), an analytical study related to the heated length effect on critical heat flux(CHF) has been carried out to make an improvement of the CHF prediction accuracy based on local condition correlations or table. It has been carried out to suggest a feasible criterion of the threshold length-to-diameter (L/D) value in which heated length could affect CHF. And within the criterion, a L/D correction factor has been developed through conventional regression. In order to validate the developed L/D correction factor, CHF experiment for various heated lengths have been carried out under low and intermediate pressure conditions. The developed threshold L/D correlation provides a new feasible criterion of L/D threshold value. The developed correction factor gives a reasonable accuracy fur the original database, showing the error of -2.18% for average and 27.75% for RMS, and promising results for new experimental data.

• 전기학회논문지
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• 제60권7호
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• pp.1434-1437
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• 2011

Precision measurement of silicon wafer resistivity has been using single-configuration Four-Point Probe(FPP) method. This FPP method have to applying sample size, shape and thickness correction factor for a probe pin spacing to precision measurement of silicon wafer. The deference for resistivity measurement values applied correction factor and not applied correction factor was about 1.0 % deviation. The sample size, shape and thickness correction factor for a probe pin spacing have an effects on precision measurement for resistivity of silicon wafer.

• 조명전기설비학회논문지
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• 제22권9호
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• pp.25-31
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• 2008

유도전동기의 자계는 전류의 방향에 따라 자화 및 감자되는 특성을 가지고 있다. 전통기의 자계를 형성하는데 필요한 자화전류는 유도성으로 무효전력의 대부분을 차지하고 있다. 무효전력은 유도전동기가 동작하는데 필요한 자계를 지속시키는 역할을 한다. 유도전통기의 역률은 낮은 편이므로 역률 보상이 필요하다. 유도전동기를 정격출력보다 낮은 부하로 운전할 경우 유효전력에 비해 무효성분의 비율증가로 역률이 낮아진다. 역률 보상장치의 용량은 전동기 정격에 맞도록 설치하기를 권고하고 있다. 그러나 부하의 운전상황에 따라 역률 보상용 커패시터 값은 수정하기가 어렵다. 본 논문에서는 저압 소용량 유도 전동기에 연결된 부하의 변화에 따라 전력 및 역률의 동작특성을 해석한 결과 기존에 제시된 낮은 역률 보상용 파라미터는 수정되어야 함을 확인하였다.

• 방사성폐기물학회지
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• 제13권4호
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• pp.295-300
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• 2015

HPGe 검출기를 이용하여 밀도가 다양한 환경시료에 대한 정밀 분석시 정확한 분석을 위해서는 밀도보정인자가 필요하다. 밀도에 대한 보정인자를 구하기 위해서 본 연구에서는 몬테카를로 코드인 MCNPX 코드를 사용하여 크리스털의 높이, 지름 및 코어의 크기와 같은 특성이 다른 세 대의 p-type HPGe 검출기를 모사하고 밀도 $1g/m^3$의 교정용 표준시료를 이용하여 모델링을 검증하였다. 검증을 통하여 모델링을 확정한 후 0.3, 0.6, 0.9, 1.0, 1.2, $1.5g/m^3$ 밀도를 가진 샘플에 대한 효율을 시뮬레이션하고 밀도보정인자를 도출하였다. 도출된 각 검출기에 대한 밀도보정인자를 비교하였을 때 전 에너지 범위에서 그 차이가 거의 없음을 확인하였으며 이는 검출기의 크리스털과 같은 주요 특성에 대해 밀도보정인자가 독립적임을 의미한다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제50권10호
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• pp.501-507
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• 2001

In this paper, new high-efficiency zero voltage switching (ZVS) AC-DC boost converter is proposed to achieve power factor correction by simplifing energy recovery circuit. A lot of high power factor correction circuits have been proposed and applied to increase input power factor and efficiency. Most of these circuits may obtain unity power factor and achieve sinusoidal current waveform with zero voltage or/and zero current switching. However, it is difficult for them to obtain low cost, small size, low weight, and low noise. The topology proposed to improve these problems can compact the devices in circuit and can achieve high efficiency ZVS AC-DC boost converter. Simulation and experimental results show that this topology is capable of obtaining high power factor and increasing the efficiency of the system.

• 대한기계학회논문집
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• 제11권1호
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• pp.132-144
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• 1987

본 논문에서는 Isida의 이론해석 방법을 참고로 하여 유한한한 폭을 갖는 두 께가 변화하는 판재에서의 응력확대계수를 2차원 이론해석한 것이다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.960-965
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• 2014

Transmission loss of specimen is calculated by measuring energy of incident and transmission and using reverberant room of large size. But normal measurement of transmission loss has trouble because it is actually demanded that large area and specimen of certain size is satisfied with condition of diffused sound field. Especially, in case of mechanical component, interested frequency band is mid-frequency band between 500 ~ 2k Hz, and it is used to be available to minimize a reverberation chamber under conditions satisfying acoustic one because production of specimen for transmission loss measurement has limit. But, as in semi-reverberation room, it is difficult to satisfy condition of diffuse sound field and modification factor is applied to complement that. Correction factor when measuring transmission loss using semi-reverberation chamber is required accuracy because it works as main factor determining reliability of reuslts on transmission loss. In this study, it is analyzed that an effect on correction factor based on varying materials and sizes of specimens in order to deduction of it. Also It is confirmed that applied by elicited correction factor with actual railway vehicle's floor has reliability.