http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
고령에서 발현한 척수외 혈관모세포종 - 증 례 보 고 -
김영우,김재건,유도성,허필우,조경석,김달수,강준기,Kim, Young Woo,Kim, Jae Keon,Yoo, Do Sung,Huh, Phil Woo,Cho, Kyuong Suck,Kim, Dal Soo,Kang, Joon Ki 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.2
Intradural extramedullary hemangioblastoma of the spinal cord is uncommon tumor. Symptom onset is typically in the forth decade. Complete excision offers the best chance for cure. We report a case of extramedullary hemangioblastoma of the spinal cord in old age. A 76 -year old man presented with 1 month history of paraparesis. Multiple enhancing lower thoracic and lumbar spinal masses were seen on magnetic resonance imaging(MRI). Surgical exploration for symptomatic lesion revealed intradural-extramedullary mass, which had hypervascularity. The excised spinal masses were diagnosed as hemangioblastoma. Postoperative course was uneventful and symptoms improved gradually.
불안정성 흉·요추부 골절에 대한 단 분절 척추경 나사못 고정술 및 추체 보강 성형술 - 예 비 보 고 -
김영우,오성한,윤도흠,진동규,조용은,김영수,Kim, Young Woo,Oh, Sung Han,Yoon, Do Heum,Chin, Dong Kyu,Cho, Yong Eun,Kim, Young Soo 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.11
Objectives : Since vertebroplasty has been introduced, we performed short segment pedicle screw fixation with augmented intra-operative vertebroplasty in patients with unstable thoraco-lumbar fracture. Our intentions are to demonstrate the efficacy and indication of this new technique compare to conventional methods. Material and Methods : The surgery comprised of pedicle screw fixations on one level above and below the fracture site, and the fractured level itself, if pedicle is intact, and intra-operative vertebroplasty under the fluoroscopic guide with in-situ postero-lateral bone graft. Also, in cases of bone apposition, we removed those with small impactor through a transfascetal route. During the last 2 years, we performed in seven(7) unstable thoraco-lumbar fracture patients who consisted of two different characteristics, those four(4) with primary or secondary osteoporosis and three(3) of young and very healthy. All patients were followed clinically by A.S.I.A. score and radiography. Results : Mean follow up period was 14 months. We observed well decompressed state via transfascetal route in cases of bone fragments apposition and no hardware pullout in osteoporotic cases, no poly-methyl-methacrylate (PMMA) leakage through the fracture sites into the spinal canal, and no kyphotic deformities in both cases during follow-up periods. All patients demonstrated solid bony fusion except one following osteoporotic compression fracture on other sites. Conclusions : In the management of unstable thoraco-lumbar fracture, we believe that this short segment pedicle screw fixation with augmented intra-operative vertebroplasty reduce the total length or levels of pedicle screw fixation without post-operative kyphotic deformity.
김영우,유재택,김수원,Kim, Yeong-U,Yu, Jae-Taek,Kim, Su-Won 대한전자공학회 2001 電子工學會論文誌-SD (Semiconductor and devices) Vol.38 No.7
In this Paper, an approximate processing method is proposed and tested. The proposed method uses variable CSD (VCSD) coefficients which approximate filter stopband attenuation by controlling the precision of the CSD coefficient sets. A decimation filter for Audio Codec '97 specifications has been designed having processor architecture that consists of program/data memory, arithmetic unit, energy/level decision, and sinc filter blocks, and fabricated with 0.6${\mu}{\textrm}{m}$ CMOS sea-of-gate technology. For the combined two halfband FIR filters in decimation filter, the number of addition operations were reduced to 63.5%, 35.7%, and 13.9%, compared to worst-case which is not an adaptive one. Experimental results show that the total power reduction rate of the filter is varying from 3.8 % to 9.0 % with respect to worst-case. The proposed approximate processing method using variable CSD coefficients is readily applicable to various kinds of filters and suitable, especially, for the speech and audio applications, like oversampling ADCs and DACs, filter banks, voice/audio codecs, etc. 본 논문에서는 많은 연산을 필요로 하는 디지털 필터의 저전력화를 위한 새로운 저전력 기법을 제안한다. 제안된 저전력 기법에서는 CSD (canonic signed digit)숫자의 유효 표현 범위를 결정하는 nonzero digit 와 ternary digit의 값에 따른 필터의 차단대역 특성 변화를 이용하여, 다단계의 필터 차단 대역 특성을 가지는 가변 CSD 계수를 얻고 이를 approximate processing 기법에 적용하였다. 제안된 저전력 필터 설계기법의 성능을 확인하기 위하여 4개의 필터 차단대역 특성을 사용하는 AC '97 과표본화 ADC용 decimation 필터의 설계에 적용하였다. Decimation필터 중 제안된 저전력 기법을 적용한 두 half-band 필터의 연산량은 제안된 기법을 적용하지 않은 경우에 비해 각각의 근사화 수준에서 단위 출력 샘플 당 63.5, 35.7, 13.9 %의 덧셈 연산만을 수행하여 필터의 출력을 얻을 수 있었다. Decimation 필터는 0.6㎛ CMOS SOG 라이브러리를 사용하여 제작·실험하였으며, 실험결과 입력 신호의 attenuation에 따라 전체 소모전력의 약 3.8 %에서 9 %의 소모전력이 감소되었음을 확인하였다. 제안된 가변 CSD 계수를 이용한 approximate processing 방식은 특히 음성 대역 및 오디오 대역의 신호처리와 과표본화 ADC/DAC의 decimation/interpolation과 같은 multirate 시스템에 적합하다.
김영우,황영하,임용진,김도향,홍준표,Kim, Y.W.,Kwang, Y.H.,Lim, Y.J.,Kim, D.H.,Hong, C.P. 한국열처리공학회 1998 熱處理工學會誌 Vol.11 No.1
The softening behavior of squeeze cast Mg-Li-Al and Mg-Li-Al-Zr alloys have been investigated. The highest hardness values of Mg-Li-Al and Mg-Li-Al-Zr alloys were obtained after solution treatment at $400^{\circ}C$ for 1 hour. The hardness value, however, decreased as the aging temperature and time increased. Microstructural and calorometric analyses showed that quenched-microstructure changed from primary (${\alpha}$ and ${\beta}$)+secondary ${\alpha}$ to primary(${\alpha}$ and ${\beta}$)+secondary ${\alpha}+{\theta}$ after aging. The softening during aging was due to the coarsening of ${\theta}$ precipitates.
김영우,이주성 ( Yeong Woo Kim,Ju Seong Lee ) 한국공업화학회 1993 공업화학 Vol.4 No.3
인산형 연료전지용 전극촉매로 많이 사용되고 있는 고가의 백금촉매의 이용가치를 높이기 위하여 촉매 담지시 백금촉매의 미립화가 매우 중요하다. 따라서 카본블랙상에 고분산화된 촉매의 제조를 위하여, 고전적 함침법, pressing & soaking법, 무전해 도금법 및 콜로이드법의 여러 가지 촉매담지방법에 관하여 연구하였다. 그리고 각 촉매담지방법에 대하여 카본블랙상 백금촉매의 담지수율 및 백금촉매 입자크기를 비교하였다. 담지수율은 DCP로 확인하였으며 입자의 크기는 XRD 및 TEM으로 관찰하였다. 결과 콜로이드방법이 백금촉매를 30Å 이하로 미립화할 수 있는 가장 우수한 촉매담지 방법이었으며 카본 담체에 대한 백금촉매의 담지수율은 99% 이상이었다. To raise the utilization of precious platinum currently used as catalyst for PAFC`s electrode, it is very important to make fine particles of platinum. This study, for preparing highly dispersed platinum catalyst on carbon black, treated various loading methods such as traditional impregnation, pressing & soaking, electroless plating and colloid method. And then loading yield of platinum catalyst on carbon black and the particle size were investigated by DCP and XRD and/or TEM respectivily. The colloid method by which platinum particle size could be reduced as small as below 30 Å showed the best result among them, and the loading yield of platinum catalyst on carbon black was above 99% .