전송선로행열에 대한 유사변환을 이용한 PCB기판 임피던스 해석

서영석,Suh, Young-Suk 한국정보통신학회 2009 한국정보통신학회논문지 Vol.13 No.10

디지털 시스템의 동작주파수가 증가하고 전압스윙폭이 감소함에 따라 PCB보드의 정확하고 빠른 해석이 중요하게 되었다. 단위 기둥 행열의 다중곱을 이용하는 전송선로 행열을 이용한 방법은 PCB보드 해석에 있어서 가장 빠른 방법이다. 본 논문에서 PCB보드 임피던스를 계산하는 새로운 방법이 제안되었다. 우선, 이 방법에서 PCB의 단위기둥에 대한 전송선로행열의 고유치와 고유벡터가 계산되고, 단위기둥에 대한 전송선로 행열은 행열요소의 곱셈횟수를 줄이기 위해 행열유사변환을 통해 변환된다. 이러한 유사변환을 방법은 기존방법에 비해 계산시간을 대폭 줄여 줄 수 있다. 제안된 방법은 가로 1.3인치 세로 1.9인치의 PCB기판에 적용되었고, 10배 정도의 계산시간저감 효과를 보였다. 제안된 방법은 보드임피던스의 반복적인 계산을 필요로 하는 PCB설계에 응용될 수 있다. As the operating frequency of digital system increases and voltage swing decreases, an accurate and high speed analysis of PCB board becomes very important. Transmission matrix method, which use the multiple products of unit column matrix, is the highest speedy method in PCB board analysis. In this paper a new method to reduce the calculation time of PCB board impedances is proposed. First, in this method the eigenvalue and eigenvectors of the transmission matrix for unit column of PCB are calculated and the transmission matrix for the unit column is transformed using similarity transform to reduce the number of multiplication on the matrix elements. This method using the similarity transform can reduce the calculation time greatly comparing the previous method. The proposed method is applied to the 1.3 inch by 1.9 inch board and shows about 10 times reduction of calculation time. This method can be applied to the PCB design which needs a lots of repetitive calculation of board impedances.

임의 형상의 금속-유전체-금속 전력배분기판에 대한 빠른 임피던스 계산 방법

서영석,Suh, Young-Suk 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.5

This paper presents a method for analyzing irregular shaped power distribution networks. The irregular shaped metal-dielectric-metal plane is split into several piece of rectangular segments to calculate the impedance of the irregular shaped plane. Impedance matrix for each rectangular segments is calculated using the Mobius transform method to reduce the calculation time. Then the segmentation and do-segmentation method is applied to the piece of rectangular segments. Applied to the 6 inch by 5 inch size irregular shaped board, the proposed method shows 10 times faster than the electromagnetic or circuit analysis method.

직사각형의 전력-접지층에 대한 전압전류 특성해석을 위한 빠른 계산방법

서영석,Suh, Young-Suk 한국정보통신학회 2005 한국정보통신학회논문지 Vol.9 No.1

기존의 금속${\cdot}$유전체${\cdot}$금속 기판형태의 전력${\cdot}$접지층 사이의 전압표현식은 2차원 무한급수 형태로 표시된다. 계산시간 단축을 위해 Fourier 급수합 공식을 이용하여 2차원 무한급수를 1차원 무한급수로 변형시켰다. 이 식들을 $9‘{\times}4'$크기를 가지는 전력${\cdot}$접지층에 대한 전압 계산에 적용했다. 유도된 1차원 급수 계산식은 기존의 2차원 급수식에 비해 빠른 수렴성과 정확한 결과를 보였다. 이 결과는 반복적인 계산이 많이 필요한 전력${\cdot}$접지층 해석에 유용하게 적용될 수 있을 것이다. The existing analytical expression for the voltage between the power and ground plane consist of metal-dielectric-metal board is expressed in the two dimensional infinite series. To reduce the computation time, the two dimensional infinite series is converted to the one dimensional infinite series using the summation formula of Fourier series. We applied these equations to the analysis of voltage between the $9‘{\times}4'$ size power-ground plane. The derived one dimensional infinite series shows the more rapid convergency and the more accurate result than the two dimensional infinite series. This equation can be applied to the power-ground plane analysis which needs a lot of the repeating computation.

역행성 후 골간 동맥 피판을 이용한 수부결손의 재건

서영석,박형택,이군식,Suh, Young-Suk,Park, Hyung-Taek,Lee, Kun-Sick 대한미세수술학회 2001 Archives of reconstructive microsurgery Vol.10 No.2

Various types of flaps including local flaps, pedicle flaps and free flap have been used to reconstruct hand soft tissue defects, but each flaps have some limitation and disadvantages. The reverse posterior interosseous artery flap described by Zancolli and Angrigiani have some advantages : preserving the major artery of the hand, minimal donor site morbidity and thin skin. From May 1999 to May 2001, we reconstructed 18 cases of hand defects in industrial injury with reverse posterior interosseous artery flaps and partial distal part necrosis of flaps due to infection developed in a case but other 17 cases survived completely without any specific complication.

무선 송수신모듈용 실리콘 바이폴라 트랜지스터의 새로운 전류원 모델링

서영석,Suh, Young-Suk 한국조명전기설비학회 2005 조명·전기설비학회논문지 Vol.19 No.3

근거리에서의 무선설비제어, 구내음성통신과 같은 전파통신설비의 송수신 모듈에 실리콘 바이폴라 트랜지스터가 많이 사용되고 있다. 이러한 실리콘 바이폴라 트랜지스터의 내부 전류원에 대한 새로운 모델링 방법이 제시되었다. 제안된 방법은 Si-BJT의 새로운 열 저항 추출방법과 전류원 파라메터에 대한 새로운 해석적인 방정식에 기반을 두고 있다. 이 방법은 기존의 방법에서 채택된 반복적인 최적화 과정 없이 바로 파라메터를 구할 수 있다. 제안된 방법을 5개의 핑거를 가지는 $0.4\times20[{\mu}m^2]$ 의 Si-BJT에 이 방법을 적용시켰으며, 모델링된 데이터는 측정결과를 $3[\%]$ 이내의 오차로 잘 예측하였다. Silicon bipolar transistors (Si-BJT) are widely used in the telecommunication system such as short range wireless control and wireless indoor voice communication system. New modeling method for the internal current source model of Si-BJT is proposed. The proposed method based on new thermal resistance extraction method and new analytical expressions for the current source parameters of Si-BJT. The proposed method can directly extract the model parameters without any optimization procedure which is adopted in the conventional modeling method. The proposed method is applied to 5 finger $0.4\times20[{\mu}m^2]$ and the model shows good prediction of the measured data in $3[\%]$ of errors proving the validity of this method.

전송선로 행열을 이용한 전력배분기판에 대한 빠른 임피던스 계산 방법

徐暎錫(Young-Suk Suh) 대한전기학회 2005 전기학회논문지C Vol.54 No.6

한지점의 바이어스에서 측정된 S - 파라메터를 이용한 HBT 등가회로 파라메터 추출을 위한 새로운 방법

서영석(Young Suk Suh) 영남대학교 정보통신연구소 1997 정보통신연구소논문집 Vol.4 No.1

N/A

이준의 구국운동과 교육사상

서영석(Young-Suk Suh) 한국기독교교육정보학회 2007 기독교교육정보 Vol.18 No.-

This paper aims to explore Jun Yi's patriotism and educational thought for the restoration of its sovereignty related to his activities in the country. Yi was a eager patriot who entered government service as a public prosecutor and participated as a member of the Independence Club. Finally, he was dispatched to the Hague on a special envoy in 1907, but died without achieving his purpose. The purpose of this paper is to maintain the basis of Yi's activities and thoughts came from Christian spirit. After 1905, Jun Yi became a Christian, and was a key member of Sangdong Methodist Church in Seoul in order to realize recovery of national sovereignty. I summed up the meanings of Yi's patriot spirit and educational thought in his whole life. First, Yi devoted himself to his country during his whole life. Especially after 1905, Yi's patriotism was originated from Christian faith of freedom and national salvation. Secondly, Yi had power of execution for Christian faith throught the spirit of cross and resurrection. He was not afraid of death, on the contrary, was to ready to die in order to restore nation' s sovereignity. He really realized the teaching of the Bible about real die and real life originated from christian courage and conviction, Thirdly, Yi had an idea of Christian justice for equal rights of people and world peace. Yi protested all kinds of injustice though he struggled through the long thorny path of life. Even though Yi's all efforts for his country ended in failure, his patriotism and educational thoughts through Christian faith show on the decisive feature of activities, and the vision of national education for his country.

대장암 검사에서 이중 대장 조영술의 유용성

서영석(Young Suk Suh) 대한영상의학기술학회 2006 대한영상의학기술학회 논문지 Vol.2006 No.1

The colonic cancer is one of frequent cancers in Korea and the incidence of colon cancer has been increasing. We have compared sigmoidscopy, colonoscopy, barium enema and abdominal CT studies one another to examine the characteristic of colon tumors in order to see if we can improve the colonic Barium Enema method. The study was done from March 1st through August 10th in 2005 for 30 patients who came to our institution with various symptoms and for whom more than two studies among barium enema, sigmoidoscopy, colonoscopy and abdominal CT had been performed with the resultant diagnosis of polyps or cancers. There were 2 patients in whom positive barium enema but with negative sigmoidoscopic exams, 1 patient in whom positive barium enema but negative colonoscopic exams, 0 patient in whom positive barium enema and also positive abdominal CT exams and 0 patient in whom negative sigmoidoscopy, colonoscopy and abdominal CT and also negative barium enema. Therefore we have concluded that the sensitivity of the double contrast barium enema reveals no less sensitivity than endoscopic examinations and also the former has been found to be more cost effective.

사무공간 적용 BIPV시스템의 자연채광 및 성능평가에 관한 연구

서영석(Seo Young-Seok),오민석(Oh Min-Suk),김회서(Kim Hway-Suh) 한국태양에너지학회 2009 한국태양에너지학회 학술대회논문집 Vol.2009 No.11월

By the skyscraper building, increase of skin area and expansion of curtain wall system will be the important factors of acceleration in extending supply of BIPV system. In the future interior environmental evaluation is not a necessary to the residents but an essential term which will bring enormous influence. In the interior environmental evaluation, natural light will let the residents with direct contact with outside circumstances and make them feel opened. also only the daylight has radiant energy and color rendering that will have a great influence to residents' mental, operation efficiency and advancing productivity. This research compares and analyzes BIPC system in office spaces with two general sunlight's module. In addition to natural light's efficiency for BIPC system's comfort and confirmed economical efficiency will be applied to basic research data. Hence forth, ensuring indoor intensity of illumination and controlling light system to reducing energy research data will be demanded to increase the amount of supplying BIPC system. Also continuance research in the possibility of applying BIPC system in various buildings, room temperature affected by location of windows and its condensation, and economical evaluation will be required.