• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1489-1491
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• 2004

PD in air is accompanied by light, sound and electromagnetic wave. Light and sound can be prevented from blocking between PD sources and sensor but electromagnetic wave can be transferred to long distance without any interference an captured by antenna. This paper investigated the wideband antenna is appropriate for sensing Partial discharge in air. PD was generated from simulated PD source which consist of needle and flat electrode with small gap. Signals obtained from wideband antenna were diminished in both time and frequence region with the distance between PD source and antenna.

• 대한안전경영과학회지
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• 제3권3호
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• pp.231-241
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• 2001

The epoxy resin materials used in outdoor high voltage equipments are required to have the high electric performance because of the miniaturization. The frequence dependence of the permittivity and the loss tangent have important information. In this paper we describe the frequency dependence of the permittivity and the loss tangent for epoxy resin filled with silica and the influence of filler shapes on the dielectric properties. The increment of tan $\delta$ in the low frequency region is caused by the increment of both the electrical conductivity and the polarization due to the shape of filler and the water absorbed in and near the interface between fillers and resins. The result of charge current and discharge measure, electric conduction is increased according to voltage.

• 대한가정학회지
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• 제27권1호
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• pp.141-164
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• 1989

The Purpose of this study is to investigate the relationship between the urban home-maker's view of homemanagement and the domestic courtesy and ritual (wedding ceremany, ancestral service, funeral rites). The data for this study was obtained from the 661 homemakers who live in Seoul, Busan, Inchon etc. The data were analyzed by the method described below with SPSS Computer programs. Such methods as frequence, percentile, analysis of variance (t-test, one-way ANOVA), Pearson's correlation and Factor analysis, Multiple regression were used. The major results the study can be summaried as follows; 1) As the result of factor analysis about view of homemanagement, 10 factors (which Eigen Value was above 1.0) out of 28 guestions were extracted. 2) In general, it can be said that the urban Homemaker's View of homemanagement varies by age, level of education, religion. 3) The domestic courtesy and ritual (wedding ceremony, ancestral servic, funeral rites) varies by age, level of education, religion. 4) There is a positive relation in analyzing the correlation between the urban homemaker's view of homemanagement and domestic courtesy and ritual (wedding ceremony, ancestral service, funeral rites)(p<.001).

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2006년도 춘계학술대회 학술발표 논문집 제16권 제1호
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• pp.257-260
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• 2006

카오스 로봇의 하드웨어 구현에서 로봇의 차제 또는 바퀴가 정확하기 자기 위치를 인식하고 지시한 방향과 거리만큼 이동하는 것이 가장 중요하다. 이를 위해 정확한 방향을 움직일 수 있는 각속도 센서는 로봇에서 매우 중요한 위치를 차지한다. 정확한 각속도 센서를 설계하기 위해서는 정확하게 전압을 주파수로 바꾸어주는 VF(Voltage to Frequence) 컨버터의 설계가 선행되어야 하며 이를 만족하는 것으로 선형성이 보장되어야 한다. 이에 본 논문에서는 VF 컨버터에서 선형성을 개선시키기 위한 방법을 제시하고 제시한 방법을 기초로 한 VF 컨버터를 설계하였다.

• 한국통신학회논문지
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• 제29권12A호
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• pp.1349-1355
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• 2004

근거리 무선통신망에 로밍 및 효율성 증대를 위하여 본 논문에서는 BOWLIS 알고리즘을 제안하였다. 제안된 BOWLIS 알고리즘은 전자기파와 같은 잡음으로부터 무선랜과 같은 근거리 통신시스템의 성능을 보호하고 유지하는 기능을 수행하게 된다. BOWLIS 알고리즘은 기존 근거리망에서 제공되는 서비스의 처리속도 및 오류에 대하여 보다 나은 성능을 보여준다.

• 한국전기전자재료학회논문지
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• 제15권8호
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• pp.713-719
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• 2002

In this study, the vertically well-aligned CNTs were synthesized by DC bias-assisted inductively coupled plasma hot-filament chemical vapor deposition (ICPHFCVD) using radio-frequence plasma of high density and that CNTs were vertically grown on Ni(300 )/Cr(200 )-deposited glass substrates at 58$0^{\circ}C$. This system(ICPHFCVD) added to tungsten filament in order to get thermal decompound and DC bias in order to vertically grow to general Inductively Coupled Plasma CVD. The grown CNTs by ICPHFCVD were developed to higher graphitization and fewer field emission properties than those by general ICPCVD. In this system, DC bias was effect of vortical alignment to growing CNTs. The measured turn-on fields of field emission property by general ICPCVD and DC bias-assisted ICPHFCVD were 5 V/${\mu}{\textrm}{m}$ and 3 V/${\mu}{\textrm}{m}$, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 B
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• pp.788-790
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• 1999

고주파 열처리 유도로의 설계에서 품질의 향상을 위하여 인버터의 고주파 기술이 요구되고 있다. 본 연구에서는 고주파 유도가열 장치의 대용량, 고주파 화를 실현하기 위하여 회로 설계 기술과 제어방식을 제안하였다. 부하 공진 인버터는 H형 전-브리지로 구성하고 각 암 당 IGBT를 2병렬로 조합하여 구성하고 부하는 직병렬 공진회로로 구성한다. 스위칭 동작은 8개의 IGBT중 각 암 당 2개씩 순차제어하여 고속 대용량의 고주파 전력을 출력시킨다. 또한 스위칭은 스위치 턴온 오프시에 스위칭 손실을 줄이기 위해 ZVS기법을 도입한다. 제어는 고정주파수 PWM제어를 하여 전력변환 효율을 극대화한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 D
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• pp.2597-2599
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• 2004

The high quality power is consisted with uniform frequence, no interruption and uniform voltage. In these components, the voltage of the distribution systems affects making economic distribution facility and improving power quality. This paper describes on the voltage apportion rates of the distribution systems in KEPCO.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.837-838
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• 2008

This paper presents a new signature and Fourier descriptor based algorithm for recognizing a rotated object and its rotation angle. Fourier descriptor is used to represent an object using its frequence parameters which are not influenced by rotation. once the object is recognized, the point with the largest auto-correlation coefficient which can be calculated from signature of the object is used to find angle of the object. The outstanding performance of the proposed algorithm has been tested with the test images where more than 10 2D objects arbitrarily located on a table.

• 한국조리학회지
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• 제14권4호
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• pp.306-316
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• 2008

The purpose of this study is to identify how and job satisfaction and job training affect service quality and to offer strategic tools for enhancing competitiveness of the food service business industry. To fulfill this purpose, this study utilized a factor analysis, frequence test, a reliability analysis and a covariance structure analysis. The results of the analyses show that one dimension such as "job training" influenced service quality. This means that restaurants should put more focus on job training to improve service quality for customers.