• 한국의류산업학회지
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• 제6권2호
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• pp.221-228
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• 2004

The purpose of this study was to compare somatotypes from various classification methods, to analyze the interrelation among each somatotype or each high frequency type, and to suggest the basis to interpret body size and shape more accurately. As a sample, the subjects were 97 Korean females between 18 and 24 years old. They were measured both anthropometric and photographic measuring in November, 1999. Their somatotypes were classified by three kinds of classification methods. The first method was based on the lateral view of body, the second involved Factor and Cluster analysis with the photographic measurements of anterior and lateral body, and the third involved Factor and Cluster analysis with the anthropometric measurements of whole body. The upper body was classified into three types, and the lower body was classified into 6 types from the lateral view of body. The bend-forward/q-2 was found to be the 'High-frequency type from the lateral view of body', and the Straight/n-1 was found to be the 'Straight type from the lateral view of body'. From the classification by the analysis of photographic measurements, the anterior body was classified into three types, the lateral was classified into 4 types. The X/${\varepsilon}$ type was found to be the 'High-frequency type from the analysis of photographic measurements of anterior and lateral body'. From the classification by the analysis of anthropometric measurements, the whole body was classified into three types. The i type was found to be the 'High-frequency type from the analysis of anthropometric measurements of whole body'. The significant interrelation was certified among some somatotypes or some High-frequency types. We found that both the view of body and the statistical analysis would make the clear definition of each somatotype possible. In order to certify the representativeness of High-frequency type, further analysis would be required of subjects who were in the High-frequency type and their body parts were in the High-frequency range.

• 조명전기설비학회논문지
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• 제28권3호
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• pp.32-43
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• 2014

This paper presents the intra capacitance modeling according to the winding method, section bobbin and coil structure for hybrid choke coil capable of the EMI attenuation of broad bands from lower frequency bands to higher frequency bands and high frequency type common-mode choke coil capable of the EMI attenuation of high frequency band used in the EMI Block of LED-TV SMPS. In case of high frequency type CM choke coil, it can be explained the parasitic capacitance of A type and section bobbin type winding methods among them is much smaller than the other. The first resonant frequency of the proposed CM choke coil tends to increase as the parasitic capacitance becomes small and its impedance characteristics also show improved performance as the first resonant frequency increases. In case of hybrid choke coil using rectangular copper wire, it has investigated its parasitic capacitance compared to CM choke coil of conventional toroidal type becomes small. Also it has confirmed through the experiment results that CE margin and RE margin in frequency bands 0.5MHz to 5MHz and 30MHz to 200MHz are respectively 10dB and 15dB greater than that of conventional type in case of one stage EMI filter structure adopting hybrid choke coil compared to two stage EMI Filter structure using two of each CM choke coil used in the lower and higher frequency bands or two of CM choke coil used in only the lower frequency bands. In the future, the hybrid choke coil and CM choke coil of high frequency type show it can be practically used in not only LED/LCD-TV SMPS but also several applications such as LED Lighting, Laptop Adapter, Server Power Supply and so on.

• 전력전자학회논문지
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• 제19권1호
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• pp.8-14
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• 2014

This paper presents the intra capacitance modeling according to the winding method and section bobbin for CM choke capable of the EMI attenuation of broad bands from lower frequency bands to higher frequency bands and high frequency type common-mode choke capable of the EMI attenuation of high frequency band used in the EMI Block of LED-TV SMPS. In case of high frequency type CM choke, it can be explained the parasitic capacitance of A type and section bobbin type winding methods among them is much smaller than the other. The first resonant frequency of the proposed CM choke tends to increase as the parasitic capacitance becomes small and its impedance characteristics also show improved performance as the first resonant frequency increases. In the future, the CM chokes of high frequency type show it can be practically used in not only LED/LCD-TV SMPS but also several applications such as LED Lighting, Adapter and so on.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권1호
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• pp.34-39
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• 2002

Most X-ray generator had been used do rectifier type transformer high tension generator which is supplied in a clinical diagnosis. But it is difficult to miniaturize and become light weight. Also, because the ripple rate of tube voltage is high, X-ray generating efficiency is very low. Therefore, it is supplied gradually from abroad being developed high tension generator for inverter type X-ray generator which use semi-conductor switching element for electric power that have high speed switching ability to solved these problem. But, semi-conductor element of big capacity are used by X-ray tube's big consumption power and diffusion is difficult in the small size hospital because production cost is ascending by doing digital control through DSP and product price becomes expensive. Therefore, in this paper, design and manufactured CR type voltage divider for feedback control of tube voltage of high frequency resonance type inverter and high tension transformer for high frequency to apply economical diffusion type X-ray generator which have wide output voltage and load extent. It is Proved do X-ray generator and stability of X-ray tube's output characteristics through an experiment.

• 한국전기전자재료학회논문지
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• 제22권8호
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• pp.641-644
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• 2009

We have studied on the microwave characteristics for the meander type inductors on the MgO substrates and $Al_2O_3$ substrates by employing 3-D high frequency simulation, respectively. Proper designs of meander type inductors were proposed and confirmed through the high frequency simulations, 5, 7, 9, 11, and 13 turns meander type inductors have been choose to analyze the electrical properties for the microwave passive component applications. The Al top electrodes have 282 nm length, 45 nm width, 100 nm thickness and 15 nm gap. The simulations were carried out from 50 MHz to 30 GHz, Frequency dependent inductances and quality factor were calculated by employing the equivalent circuit model of meander type inductors. The self resonances frequency of meander type inductor were shifted from high frequency to low frequency range as the number of the turn of inductors was increased. From the microwave simulations, the inductances and quality factors of meander type inductors were extracted through the scattering parameter.

• 인지과학
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• 제25권2호
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• pp.91-107
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• 2014

음절 빈도 효과란 고빈도 음절로 시작되는 단어가 저빈도 음절로 시작되는 단어에 비해 어휘 판단 속도가 느리며 어휘 판단 오류율도 증가하는 효과를 의미한다. 이 효과를 유발하는 원인은 전체 단어 수준에서 활성화된 음절 이웃 단어의 방해로 알려져 있으며 이 방해의 크기는 표적 단어가 얼마나 많은 음절 이웃 단어를 또는 얼마나 강력한 음절 이웃 단어를 가지고 있는지에 의해 결정된다. 그러나 음절 빈도의 정의가 음절 타입 빈도와 토큰 빈도로 구분됨에도 불구하고 이를 구분하지 않고 많은 연구들이 수행되어 왔다. 최근 Conrad, Carreiras, & Jacobs(2008)에 따르면 음절 토큰 빈도는 전체 단어 처리 수준을 반영하는 변인이며 음절 타입 빈도는 하위 어휘 처리 수준의 음절 처리 수준을 반영하는 변인일 수 있다고 주장하였다. 이에 본 연구는 이들의 주장이 맞다면 음절 타입 빈도는 단어 명명 속도를 촉진 시킬 것이며 반대로 음절 토큰 빈도는 명명 시간과 관련 없을 것이라고 예측하였다. 왜냐하면 표기 심도가 얕고 음절의 경계가 명확한 언어에서 명명 과제는 전체 단어수준을 덜 참고하기 때문이었다. 실험 1결과에서 음절 토큰 빈도를 통제한 상태에서 고빈도 타입음절의 단어 명명 시간은 유의미하게 짧았다. 실험 2에서 음절 타입 빈도를 통제한 상태에서 음절토큰 빈도의 증가는 명명 시간을 역시 단축시켰다. 이에 본 연구는 음절 토큰 빈도가 하위 어휘 처리와 무관하다는 Conrad, Carreiras, & Jacobs(2008)의 주장을 반박하였다.

• 전기전자학회논문지
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• 제27권4호
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• pp.587-600
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• 2023

본 논문에서는 315W급 65인치 UHD-TV용 LLC DC to DC 공진 컨버터에 사용되고 있는 Slim형 고주파 변압기의 최적화 설계에 대해서 나타낸다. 또한 본 논문에서는 LLC 공진 변압기의 코어 손실 분석, AC 권선 손실 분석 및 권선 배치 최적화 설계를 통해 Slim형 고주파 변압기의 최적화 설계를 수행한다. 특히 본 논문에서는 이론적으로 해석하여 얻어진 결과를 토대로 고효율 및 Slim형 고주파 변압기는 교류 권선 손실 최소화 및 권선 자동화를 위하여 인터리브 및 수직형 권선 구조로 구성한다. 본 논문 제안한 수직형 권선 구조 방식의 Slim형 고주파 변압기의 1차측 권선은 Litz 권선을 2차 권선은 PCB와 동판 권선을 사용하였다. 최종적으로 Maxwell 2D 및 3D Tool을 이용한 시뮬레이션 결과를 토대로 이론 해석의 정당성을 입증하기 위해서 실험 결과를 통해 본 논문에서 제안한 Slim형 고주파 변압기의 최적화 설계를 수행하였다.

• 전력전자학회논문지
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• 제20권2호
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• pp.137-143
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• 2015

This paper presents the intra capacitance modeling based on the winding method and section bobbin for CM choke capable of EMI attenuation of broad bands from lower to higher frequency bands and high frequency type common-mode choke capable of EMI attenuation of high frequency band used in the EMI Block of LED-TV SMPS. The case of high frequency type CM choke can be explained by the parasitic capacitance of three types of CM choke. The winding method of section bobbin type is smaller than the others. The first resonant frequency of the proposed CM choke tends to increase as the parasitic capacitance becomes small and its impedance characteristics improved performance as the first resonant frequency increases. The CM chokes of the proposed section bobbin type shows that in the future, the method may have practical use in LED/LCD-TV SMPS and in several applications, such as LED lighting, adapters, and so on.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.798-801
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• 2000

For the performance enhancement of communication system, high quality filters are required. Also a minimization of size of filter is required for the interation of devices in the limited area. Conventional metal filters made of copper can be substituted by high quality high temperature superconducting(HTS) films for better performance. Hairpin type filters have been designed with the center frequency 14 GHz for the size reduction. 3-pole and 4-pole filters centered at 14 GHz with the bandwidth of about 300 MHz were designed and fabricated. With the simulation results, the frequency responses showed low insertion loss and sharp skirts characteristics. The frequency response of HTS 14 GHz fi1ter was measured at 77 K and compared with the simulation results. We have compared YBCO filters and copper filters which were made with the same design rules. Simulated and measured frequency responses reveal that HTS YBCO hairpin type bandpass filters show better performance than copper filters.

• Journal of Electrical Engineering and Technology
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• 제1권2호
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• pp.216-225
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• 2006

This paper presents a new circuit topology of DC busline switch and snubbing capacitor-assisted full-bridge soft-switching PWM inverter type DC-DC power converter with a high frequency link for low voltage large current applications as DC feeding systems, telecommunication power plants, automotive DC bus converters, plasma generator, electro plating plants, fuel cell interfaced power conditioner and arc welding power supplies. The proposed power converter circuit is based upon a voltage source-fed H type full-bridge high frequency PWM inverter with a high frequency transformer link. The conventional type high frequency inverter circuit is modified by adding a single power semiconductor switching device in series with DC rail and snubbing lossless capacitor in parallel with the inverter bridge legs. All the active power switches in the full-bridge inverter arms and DC busline can achieve ZVS/ZVT turn-off and ZCS turn-on commutation operation. Therefore, the total switching losses at turn-off and turn-on switching transitions of these power semiconductor devices can be reduced even in the high switching frequency bands ranging from 20 kHz to 100 kHz. The switching frequency of this DC-DC power converter using IGBT power modules is selected to be 60 kHz. It is proved experimentally by the power loss analysis that the more the switching frequency increases, the more the proposed DC-DC converter can achieve high performance, lighter in weight, lower power losses and miniaturization in size as compared to the conventional hard switching one. The principle of operation, operation modes, practical and inherent effectiveness of this novel DC-DC power converter topology is proved for a low voltage and large current DC-DC power supplies of arc welder applications in industry.