• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(1)
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• pp.477-480
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• 2003

Generally, 2 phase excited brushless DC motor(BLDCM) operates only in the region of constant trapezoidal back-EMF on each phase. Therefore the efficiency decreases in comparison with 3phase excited BLDCM. This paper proposes the relation between the usage ratio of voltage and the change of fewer delivery of BLDCM according to extension of conduction intervals.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 춘계학술대회논문집
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• pp.421-425
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• 2005

A distributed FBG temperature sensor system was constructed for the use in protection of electric power system. A F-P wavelength tunable filter is used converting temperature-induced wavelength variations to temporal peak locations. We used Gaussian line-fitted algorithm to alleviate the error caused by quantization and electrical noises. The experimental results showed much better accuracy than the raw peak-detection scheme.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 학술대회 논문집 전문대학교육위원
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• pp.97-100
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• 2007

There are regulations on each building for its classification and It is corresponding determined contract demand. For transformer's capability calculation algorithm, cumulated power information of each customer is used to analysis the correlation between power usage and Demand Rate. By modeling this using Least Square Method, it can be targeted to recognize the pattern of transformer use in the past and make a prediction on it in the future.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1584-1587
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• 2005

Although the picture quality of today's displays is very good already, a continuous improvement is desirable as the new larger display sizes increase the visibility of artifacts. A contributing factor for picture quality enhancement through smart video processing and algorithm design is the information gathered from video statistics. Interesting parameters gathered from video statistics are e.g. the image- and display load, the usage of the color gamut, the estimated power consumption and the occurrence of static image parts. Examples of applications that can benefit from video statistics are power calculations, color gamut mapping algorithms, dynamic backlight control for LCD panels and LED backlights for LCD panels.

• 정보관리연구
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• 제20권1호
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• pp.86-116
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• 1989

원자력발전정보(原子力發電情報)의 이용(利用)을 극대화하기 위한 정보관리(情報管理)시스템 개발(開發)을 목적으로 국내(國內)의 운영현황(運營現況)과 선진국(先進國)의 운영현황(運營現況)을 분석하였으며, 아울러 새로운 시스템개발시(開發時)에 고려해야 할 사항들을 도출하여 제시하였다.

• 한국콘텐츠학회논문지
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• 제19권10호
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• pp.59-68
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• 2019

최근 소비과정의 경험적 가치를 추구하는 소비 트렌드를 보이며, 도심 특급호텔의 핵심고객으로 변모한 내국인들의 특급호텔 이용의 지속적인 성장세를 위해서 내국인 고객이 추구하는 경험가치의 요인에 대한 연구가 필요하다. 연구 결과, 특급호텔 내국인 이용객의 경험가치 중, 환상성 요인이 이용만족의 주요 선행요인으로 확인되어, 특급호텔은 내국인 이용객이 선호하는 다른 세계 경험, 색다른 경험, 수준 높은 경험과 같은 감성적 가치를 위해 특별한 컨셉과 분위기를 반영하는 것이 중요한 과제로 확인되었다. 그리고 이익성이 이용만족에 정(+)의 영향을 미치는 선행요인으로 확인되어 경제적 효용에 대한 요구가 중요한 것으로 확인되었다. 이는 합리적 요금으로 충분한 혜택을 느낄 수 있는 가성비 좋은 상품개발의 필요성이 제기된다. 이용만족과 지속적 이용의도와의 관계에서 성별, 직업별 특성이 조절역할을 하는 것으로 나타났다. 즉, 이용만족 고객 중 남성, 그리고 전문직과 자영업 직업을 가진 고객들이 여성 및 타 직업 고객들 대비하여 지속적 이용의도를 높게 가지는 것으로 확인되었다. 이는 결국 경제력이 있는 고객이 특급호텔의 지속적 반복고객이 될 가능성이 높다는 결과로 나타나 우수소비계층을 집중으로 한 보다 차별화되고 특화된 상품개발, 서비스 및 분위기 연출 등의 마케팅 활동의 강화에 대한 필요성을 살펴볼 수 있었다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제3권1호
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• pp.47-54
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• 2003

New efficiency enhancement techniques have been devised and implemented to InGaP/GaAs HBT MMIC power amplifiers for W-CDMA mobile terminals applications. Two different types of bias current control circuits that select the efficient quiescent currents in accordance with the required output power levels are proposed for overall power efficiency improvement. A dual chain power amplifier with single matching network composed of two different parallel-connected power amplifier is also introduced. With these efficiency enhancement techniques, the implemented MMIC power amplifiers presents power added efficiency (PAE) more than 14.8 % and adjacent channel leakage ratio(ACLR) lower than -39 dBc at 20 dBm output power and PAE more than 39.4% and ACLR lower than -33 dBc at 28 dBm output power. The average power usage efficiency of the power amplifier is improved by a factor of more than 1.415 with the bias current control circuits and even up to a factor of 3 with the dual chain power amplifier.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권4호
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• pp.1-8
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• 2017

Efficient groundwater management requires accurate information about the water volume used. The pumped volume of groundwater can be indirectly estimated using empirical formulae based on electric power consumption. The purpose of this study is to test the accuracy of this indirect method. The Haean basin in Gangwon is located in a rural area, where majority of the groundwater extracted is used for irrigation. The pumped volume of groundwater indirectly estimated from electricity usage using these empirical formulae was compared with the actual pumped volume determined by conducting experiments on April 29 and May 19, 2017. The field survey collected data on electricity usage, pumped volume, and groundwater levels. Based on this measured data, correlations were calculated between electricity usage and pumping volume, as well as groundwater level and pumping rate. The results show that electricity usage and pumped volume measured for both wells (YHE1 and YHE2) are highly correlated (r=0.99, p<0.001). However, for YHE1, notably, the correlation between the groundwater level and pumping rate was not significant, and only some correlations were identified for these variables for the YHE2 test well. The average error with respect to the estimation of the actual pumped volume from the existing formula (1) and formulae (2) and (3) are +399% and -88%, respectively. To reduce these errors, these formulae need to consider other factors affecting the pumped volume.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.918-923
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• 2011

On AC railway systems, the neutral sections are installed in front of substations and sectioning posts in order to avoid crash between power that have differing phases. In case railway vehicles pass through these neutral sections, it is necessary for them to switch to coasting driving by notch-off. This may reduce speed of the vehicles, resulting lowered train operation efficiency. The usage of automatic power switching systems makes it possible to pass neutral sections at notch-on, enhancing operation efficiency so that it is appropriate for high-speed railway applications. This paper introduces a simulator that assesses efficiency of automatic power switching systems in neutral sections. The is composed of a power supply system, electric railway vehicles, thyristor switches, and traction motors.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.800-804
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• 2005

Load flow and short circuit fault transients of a power distribution system with wind turbines as dispersed generation units is presented. Usage of renewable energies such as wind is already a small part of total installed power system in medium and low voltage networks. In this paper, a radial power distribution system with wind turbines is simulated using DIgSILENT PowerFactory software for their influence on load flow and short circuit fault transients. Short fault occurring in dispersed generation systems causes some problems for the system and costumers such as fault level increase or the problems of sudden fluctuations in the current, voltage, power and torque of the double fed induction machine utilized in the wind turbines which have been studied and investigated.