전절권 VRM에서의 상호 및 자기 인덕턴스의 산정에 관한 연구

백승규,황영문 釜山大學校生産技術硏究所 1996 生産技術硏究所論文集 Vol.51 No.-

VRM은 다른 전동기에 비해 높은 자속밀도에서 운전시키는 단방향 전동기구이다. 또한 VRM의 전동력은 자기회로에서 릴럭턴스를 최소로 하는 방향으로 발생시킨다. 따라서 인던턴스의 적절한 산정은 VRM의 운전특성을 결정짓는 중요한 요소이다. 본 논문에서는 전절권 VRM의 자기 및 상호 인덕턴스를 자기회로에서 자기포화를 고려한 퍼미언스법으로 산정하고 그 타당성을 실험으로써 입증하였다. A VRM is single excited machine with high saturation. It's torque is developed by tendency for the magnetic circuit to adopt a configuration of minimum reluctance. Therefore, calculating the inductance is main factor in the study of VRM. This paper suggests the self and mutual inductance estimation method in Full-pitched winding VRM as permeance method considering the saturation in magnetic circuit. And the validity of the suggested method is verified through the test result.

Interleukin-2가 Mouse 간실질세포의 미세구조에 미치는 영향

손승국,백태경,이규식,정호삼 한양대학교 의과대학 1990 한양의대 학술지 Vol.10 No.1

It is well known that interleukin-2, a kind of lymphokine produced by the lymphocytes stimulated by antigen or mitogen, mediates antitumor effects by stimulating the proliferation of helper and cytotoxic T-cells, augmenting the tumorlytic activities of natural killer cell and promoting the differentiation of precusor T-cell into lymphokine activated killer cell in vivo. Thus interleukin-2 has been widely used as immunotherapeutic agent for various sarcoma and carcinoma and also regressed the metastasis of malignant tumors. Although interleukin-2 is beneficial to cancer patient, it also develops many toxic effects such as fever, chillness, general malaise, mental confusion, vomiting, diarrhea, hepatic and renal dysfunction, and capillary leakage syndrome, including the general edema, heavy weight gain, ascites any pulmonary edema, which limits clinical use of interleukin-2. The author undertook this experiment to pursue the effect of interleukin-2 on the ultrastructure of hepatocyte in mice. A total of 75 healthy male DDY mice, weighing about 20gm, were used as experimental animals. The experimental animals were divided into the control and interleukin-2 treated groups, and then interleukin-2 treated mice were subdivided into 6 hours, 12 hours, 24 hours and 48 hours groups by intervals of time after administration and each group allocated 15 mice. Mice of interleukin-2 treated group were administrated with 2 million unit of interleukin-2, per kg of body weight, diluted in intraperitoneally. Animals were sacrificed 6,12,24 and 48 hours after administration. The specimens, left anterior hepatic lobe, were prefixed in 2% glutaraldehyde-2,\.5% paraformaldehyde solution buffered by Millonig's phosphate buffer (pH 7.2) for 2-4 hours and postfixed in 1% osmium tetroxide buffered by same buffer solution for 2 hours at 4℃. After dehydration, the specimens were embedded in Epon 812 and the ultrathin sections, 600-800A inthickness, were made with LKB V ultramicrotome. The preparations were stained with uranyl acetate and lead citrate and observed with JEM 100cx-II electron microscope. The result obtained were as follows; 1. Dilation, sacculation and disruption of cisternae of rough endoplasmic reticulum accompanied with dissociation of membrane bound ribosome were observed but as time goes by, these changes were recovered. 2. Disorganization of mitochondria was observed. 3. Proliferations of smooth endoplasmic reticulum associated with depletion of glycogen particles was recognized. But as time goes by, the glycogen particles were represented. 4. Numerous variously sized autophagic vacupoles and multivesicular bodies were observed. 5. Numerous lipid droplets were observed but they were disappeared as time goes by. Based on the result obtained, it is suggested that interleukin-2 would induce changes of ultrastructures of hepatocyte in mouse but these changes were recovered as time goes by.

어류 성장에 있어서 식물 및 동물플랑크톤의 먹이기여도

김백호,김미연,최환석,김정중,최민규,박승택,정연태,高村典子 원광대학교 환경과학연구소 2000 環境科學硏究誌 Vol.9 No.1

내부 디자인을 고려한 강당의 음향설계에 관한 연구

방승기,백용규 성신여자대학교 산업미술연구소 1999 産業美術硏究 Vol.15 No.-

The acoustical design for the well-functioning of auditorium is one of the very important factors in auditorium-designing process. To maintain enjoyable acoustical environment, the design, which requires both in-depth knowledge and experience, should be taken into account from the planning stage. When unexpected problems regarding acoustical environment arise due to the ignorance of the acoustical basics, it becomes technologically difficult and economically inefficient to cope with the problems on an ex-post. basis. Therefore, the timely design from the initial stage guarantees desirable acoustical conditions in auditorium.

열복사의 색수차 공간여과를 이용한 레이저 용접 감시기술

김민석,백성훈,박승규,정진만,김철중 한국레이저가공학회 1999 한국레이저가공학회지 Vol.2 No.2

An innovative real-time weld monitoring technique using chromatic filtering of the thermal radiation from a weld pool is developed. This thermal radiation from the weld pool is focused on an aperture and the transmitted thermal radiation is monitored at two wavelengths with high-speed single-element detectors. Due to the chromatic aberration introduced in the focusing optics, the transmittance curve of thermal radiation varies by the wavelength. Owing to this difference in the transmittance, the local variation of thermal radiation from the weld pool can be monitored by processing the two spectroscopic signals from two detectors. In this paper, the algorithms to monitor the laser power on the weld specimen and the focus shift are investigated and the performances of laser power and focus monitoring are shown for a pulsed Nd:YAG laser welding. The monitoring of the weld pool size variation is also discussed.

익산시 주변 하천 담수조류군집의 다양성에 대하여

최환석,김미연,김백호,최민규,박승택 원광대학교 환경과학연구소 2000 環境科學硏究誌 Vol.9 No.1

β-Fluoro-α-phenylpyrrole 유도체의 합성에 관한 연구

郭炅喆,吳賢哲,鄭悳商,李英行,白承和,金鍾洙,蔡奎允 濟州大學校 基礎科學硏究所 2001 基礎科學硏究 Vol.14 No.2

플루오르가 선택적으로 치환된 유기화합물은 모체 화합물 보다 향상된 생리활성을 지니는 경우가 많이 보고 된바 있다. 이는 할로젠족 원소인 플루오르의 큰 전기음성도 때문에 비교적 강한 탄소플루오르 결합 형성 및 증가된 리피드 용해도 때문이다. Pyrrole과 그의 유도체들은 폴리머, 의약품 그리고 염료 등에 광범위하게 사용되어 왔고 오래 전부터 잘 알려진 화합물이다. 최근 자연계에서 산출되거나 합성 가능한 플루오르가 선택적으로 치환된 fluoropyrrole 유도체들은 진통제, 소염제 및 살균제 등으로 다양하게 이용될 수 있음이 알려져 있기 때문에 fluoropyrrole 유도체의 합성에 대한 연구가 활발히 진행되고 있다. 일반적으로 플루오르는 반응성이 매우 커서 유기화합물에 대한 선택적인 플루오르기의 도입이 극히 제한적이다.

Signal Processing Techniques to Detect a Surface-Breaking Crack by Using a Laser Surface Wave

Seung-Kyu Park,Chang-Hwan Lim,Hyung-Ki Cha,Hyun-Kyu Jung,Sung-Hoon Baik,Young-June Kang,Young-Sang Joo 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.51 No.I

A laser ultrasonic system is a non-contact inspection device with a high spatial resolution and it is applicable to hard-to-access locations as in a nuclear power plant. In this research, we have attempted to detect the depth of a surface-breaking crack by using the surface wave of laser ultrasound. We have investigated the variation of the peak-to-valley value in the time domain and the spectrum distribution in the frequency domain according to the crack depth. We developed several signal processing techniques to detect crack-depth information by using a normalized peak frequency variation and the attenuation of the high-frequency part of a normalized transfer function spectrum with a half-period window. Here, we describe the hardware configurations of the laser ultrasonic inspection system and the experimental results to detect a surface-breaking crack. Though the signal variation of the laser surface wave is considerably high, we experimentally confirmed that the attenuation of the high-frequency part of the spectral signal in the frequency domain provides better information about the crack depth than the amplitude variation of the ultrasonic signal in the time domain.

Electrical Parameter Evaluation of 1 MW HTS Motor via Magnetically Stored Energy Calculation

Seung-Kyu Baik,Young-KiI Kwon,Ho-Min Kim,Jae-Deuk Lee,Yeong-Chun Kim 한국초전도저온학회 (구 한국초전도저온공학회) 2010 한국초전도저온공학회논문지 Vol.12 No.2

Design and Analysis of 1 MW Synchronous Machine via 3D Magnetic Field Calculation

Seung-Kyu Baik,Young-Kil Kwon,Eon-Young Lee,Jae-Deuk Lee,Jung-Pyo Hong,Yeong-Chun Kim,Tae-Sun Moon,Heui-Joo Park,Woon-Sik Kwon Institute of Electrical and Electronics Engineers 2007 IEEE transactions on applied superconductivity Vol.17 No.2

<P>A 1 MW class superconducting synchronous rotating machine has been designed as a draft based on 2-dimensional (2D) magnetic field distribution considering several conditions such as superconducting wire length, machine efficiency, size and so on. By the way from 2D design it is not possible to consider the effect of end coils and end portions of stator iron yoke especially in superconducting machine with air-cored structure which increases magnetic field difference between 2D and 3D analysis. In this paper electrical design based on the 3D magnetic field distribution is conducted to get more proper design result and reduce design errors from 2D design approach. As the machine has larger capacity, the superconducting machine will show the advantages more and more over the conventional machine. Although the advantages at 1MW rating are not so great, the 3D design approach to get more optimized result would be very helpful for larger superconducting synchronous machine design. Through 3D analysis such as EMCN (equivalent magnetic circuit network) method and Flux-3D FEM (finite element method), we could get smaller machine size, higher efficiency, and smaller Bi-2223 HTS (high temperature superconducting) wire length than the 2D design result. Moreover influence of an important parameter, synchronous reactance, has been analysed on the machine performances such as voltage variation and output power.</P>