• 한국자기학회지
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• 제5권5호
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• pp.395-398
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• 1995

For the core loss measurement under arbitrary waveform of magnetic induction, we have constructed a single sheet core loss measuring system which consists of yoke apparatus for single sheet of $10\;cm{\times}10\;cm$, arvitrary waveform synthesizer, B-feedback system, and two channel transient recorder. Using the constructed measuring system, we can measure core loss including higher harmonics up to 2 kHz. Core loss of non-oreinted electrical steel was increased exponentially when higher harmonic frequency was increased or amplitude of harmonic induction was increased.

• 한국의상디자인학회지
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• 제11권2호
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• pp.1-10
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• 2009

The purpose of this study is to investigate harmonious color schemes based on a length proportion of upper and lower parts of a body by; understanding of the harmonious length proportion of a square measure of a color in color coordination of fashion design, and presenting a mutual relation of the length proportion of a square measure of a color according to the various way of color schemes and proportions. For this study, monochromatic scheme, analogous scheme and complementary scheme were adapted as the color schemes, and each color scheme was coordinated by analogous tone and contrast tone. Also, 1:1 symmetry proportion, 1:2 harmonic proportion, 1:1.618 golden section, 1:3 and 1:5 contrast proportion were used as the square measure of a color. For the survey, 12 sets of color sample were organized. The survey was conducted 182 of university students majored in fashion design, and 143 responded samples were analyzed using SPSS 12. The result of the study is as follows: 1:5 contrast proportion is most inharmonious in general, and 1:1 symmetry proportion is followed. It is thought that too much or same length of the square measure of colors has less attractive effect of coloring. On the other hand, 1:1.618 golden section and 1:2 harmonic proportion are accepted to be harmonious in all color schemes. The length proportion of the square measure of a color had more influence on harmony of color coordination in fashion design rather than color schemes. Though, on the assumption that people have a similar perception about the color image of fashion design, it will play an important role in strengthening or diminution of color in cloth if the coloring effect of the length proportion of the square measure of a color is used in fashion design and wearing of clothes.

• 전기학회논문지P
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• 제57권2호
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• pp.192-197
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• 2008

The value of this paper is to use reduced size apparatuses to perform field measurement in order to identify and validate that the harmonic-current effects are due to the presence of self-excitation capacitance connected at stator's terminals of the studied SEIG. This paper has presented the measured electrical quantities of a three-phase $\Delta$-connected wind induction generator (WIG) under sudden connection and disconnection of resistive loads. An intelligent power-system recorder/monitor has been employed to measure three-phase voltages and currents of the studied system at the terminals of the studied WIG and the load. The measured electrical quantities have been analyzed. Total harmonic distortion (THD) of current using cumulative probability density function has been employed to determine the penetration of harmonic distortion at load side. The results show that the harmonic currents generated by the studied WIG can be severely amplified by the connected self-excited capacitance at the stator's terminals.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제52권2호
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• pp.68-79
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• 2003

We estimated harmonics on power system of AC railway based on quantitatively measured harmonics and investigated the need of facilities for harmonics reduction. In order to analysis harmonics which inflow into power system due to increase in collector voltages and harmonic currents generated from the train when the railway is in operation, the railway system Is sectioned into power supply, railway line, AT, sectioning Post and subsectioning post. For analysis of extension of currents resulting from the railway loads, PWM converter, VVVF inverter and the feeder system are modeled based on the dynamic node technique(DNT). In order to test the usefulness of the DNT for analysis of harmonic effects, the measured harmonic currents and harmonic magnification ratios at the S/K substation are compared with simulation results using DNT modelling, which include the results for two cases with and without filters for suppression of harmonic currents. When 8 cars(4M4T) are in operation, the total sum of harmonic currents resulting from the train at M and T phases, which inflow into the substation along with the railway line, is calculated. Using the harmonics analysis program for railway feeder system with these data, the total harmonic distortion factor(710) at the outgoing point of KEPCO substation is computed. The calculation shows that when the maximum THD at the receiving point of H/K substation was 0.0443% which is much lower than 1.5% which is the allowable value of KEPCO at 154kV as well as IEEE-519 above 132kV This result indicates that any measure for harmonics reduction in Incheon International Airport Railway is not needed.

• 한국정보통신학회논문지
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• 제7권2호
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• pp.177-182
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• 2003

본 연구는 유사음에 강인한 음성인식을 위하여 음성의 유ㆍ무성음 척도를 특징 파라미터에 추가 구성하여 음절과 음소단위의 음성인식을 행하였다. 이를 위하여 피치검출에 이용되는 알고리듬인 HPS(Harmonic Product Spectrum)의 스펙트럼 정보를 이용하여 유ㆍ무성음의 정도를 나타내는 척도를 제안한다. 제안된 척도는 HPS의 첨도와 피크의 개수 그리고 높이척도이다. 이들 척도 값을 포함하여 특징 파라미터를 재구성하고 제안된 특징의 유효성을 검증하기 위하여 CVC형 유사 음절 DB하에서 기존 특징 파라미터와 비교하여 음성인식 실험을 행하였다.

• 음성과학
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• 제7권2호
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• pp.85-95
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• 2000

In this paper, the H1*-H2* measure is introduced and exact procedures for obtaining the H1*-H2* value are fully specified, The H1*-H2* measure (a corrected difference in dB between the first and second harmonics) has been devised to provide an acoustic correlate of the phonation mode of a vowel following a consonant. With this measure, we can investigate the phonation mode of a vowel that is free from the F1 amplitude perturbation effect caused by the preceding consonant, which is especially salient at the voicing onset position of the vowel. For identical research purposes, on the other hand, the H1-H2 measure (the observed difference in dB between the first and second harmonic) has been employed in many previous studies. This paper compares these two measures by illustrating experimental results of exploring post-release phonation modes of vowels following the different manner classes of stop consonants in Korean $\square$i.e., the tense, lenis, and aspirated stops.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.202-203
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• 2006

The equipment using the Power electronic device is recently increased in the distribution system, so power utility and customers increase in concerning about harmonics level. Accordingly, The power utility which prepares a measure for the harmonic public standard and manege process must analysis of the harmonics level and the effect on equipment interconnecting distribution system. In the past, the measurement equipment and technique is imperfect, so very difficult to investigate the harmonics and trend. But the improvement of the measurement equipment recently is possible to obtain the data realtime for harmonic analysis. In this paper, we research the measuring domestic harmonic and constructing of DB based on the IEC standard.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.178-180
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• 2002

Limitation countermeasure on harmonics occurred by power conversion installation, motor speed control equipment, and so on of power system is very important problem, and first of all, accuracy harmonics analysis in system is required for appropriate limitation counterplan. Analysis and judgement on power system harmonic by measurement are needed because analysis by mathematical model generally used for these harmonic analysis, if nonlinear ingredient is included in system, is not relatively correct. So, in this paper, system to measure and analyze harmonic by installing it in a power system, using DSP(Digital Signal Processor), is designed and developed. Also, it's performance is verified by installing it in the system that harmonics occurred.

• 소음진동
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• 제10권4호
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• pp.596-601
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• 2000

Propeller shaft is one of the main excitation source in the vehicle driveline. This paper presents the correlation of the propeller shaft and axle vibration. 10 D.O.F. lumped mass model is constructed to simulate the dirveline. Experimental apparatus is constructed to verify the simulation model and to measure the vibration signal of lthe driveline. The results of simulation and experiments show that propeller shaft excitation is 2nd harmonic of the rotational frequency. Axle housing vibration signal shows that axle resonate with 2nd harmonic of excitation frequency due to universal joint effect.

• 조명전기설비학회논문지
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• 제19권1호
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• pp.117-123
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• 2005

본 논문은 허브공항으로의 기능을 담당하고 있는 인천국제공항 여객터미널의 전력품질을 측정하고 분석하여 이에 대한 대책에 관하여 방법을 제시하였다. 각 Load Center는 인천국제공항 여객터미널을 운영하는 수용가의 PCC 점이라 할 수 있다. 그러므로 Load Center의 전력품질을 안전하고 안정적으로 유지하는 것이 중요하다고 할 수 있다. 이를 위해 각각의 위치에 있는 부하 측정지점에서 고조파를 측정${\cdot}$분석하여 대책수립을 위한 Filter의 종류를 제시하였다.