http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
腰椎間板脫出症에서의 脊髓造影術所見과 手術所見과의 比較考察
申東輝,金國起,朴慶洙,崔吉洙 대한신경외과학회 1975 Journal of Korean neurosurgical society Vol.4 No.2
The virtues of the pantopaque myelography in the study of the herniated intervertebral disc have been generally accepted. As expected, it shows the presence of ruptured disc in the accuracy over 80%. But it is open to discussion whether the myelographic defects can indicate the exact location and type of herniated discs or not In this article, we attempted to find out some correlation between the myelographic defect and the operative finding in viewing the size and shape of myelographic defects. This consideration may be helpful to make a clear cut diagnosis in the lumbar disc disease. One hundred and sixtytwo operative cases undergoing pantopaque myelography were subjected. Some obtained results will be presented.
RF스퍼터링법으로 성장시킨 n-ZnO 박막과 n-ZnO/p-GaN 이종접합 LED의 특성
신동휘,변창섭,김선태,Shin, Dongwhee,Byun, Changsub,Kim, Seontai 한국재료학회 2013 한국재료학회지 Vol.23 No.3
The ZnO thin films were grown on GaN template substrates by RF magnetron sputtering at different RF powers and n-ZnO/p-GaN heterojunction LEDs were fabricated to investigate the effect of the RF power on the characteristics of the n-ZnO/p-GaN LEDs. For the growth of the ZnO thin films, the substrate temperature was kept constant at $200^{\circ}C$ and the RF power was varied within the range of 200 to 500W at different growth times to deposit films of 100 nm thick. The electrical, optical and structural properties of ZnO thin films were investigated by ellipsometry, X-ray diffraction (XRD), atomic force microscopy (AFM), photoluminescence (PL) and by assessing the Hall effect. The characteristics of the n-ZnO/p-GaN LEDs were evaluated by current-voltage (I-V) and electroluminescence (EL) measurements. ZnO thin films were grown with a preferred c-axis orientation along the (0002) plane. The XRD peaks shifted to low angles and the surface roughness became non-uniform with an increase in the RF power. Also, the PL emission peak was red-shifted. The carrier density and the mobility decreased with the RF power. For the n-ZnO/p-GaN LED, the forward current at 20 V decreased and the threshold voltage increased with the RF power. The EL emission peak was observed at approximately 435 nm and the luminescence intensity decreased. Consequently, the crystallinity of the ZnO thin films grown with RF sputtering powers were improved. However, excess Zn affected the structural, electrical and optical properties of the ZnO thin films when the optimal RF power was exceeded. This excess RF power will degrade the characteristics of light emitting devices.
외상성 중경망동정맥루 3예 : report of 3 cases
신동휘,한대희,김현집,채진,최길수,심보성 대한신경외과학회 1975 Journal of Korean neurosurgical society Vol.4 No.1
The traumatic middle meningeal arteriovenous fistula is a rare condition complicated from head injury and usually found incidentally by carotid angiography. A few articles reported prevlously showed this condition is formed due to tearing of the walls of middle meningeal vessels by skull fracture and regarded as a wonderful defence mechanism keeping from a big intracranial hematoma. We have encountered 3 cases of them, all of which were accompanied by skull fracture. One of them had a big epidural hematoma and others only small amount. We show these cases in detail with the review of literatures.
RF 출력이 ZnO 박막의 전기·광학적 특성에 미치는 영향
신동휘,변창섭,김선태,Shin, Dongwhee,Byun, Changsob,Kim, Seontai 한국재료학회 2012 한국재료학회지 Vol.22 No.10
ZnO thin films were grown on a sapphire substrate by RF magnetron sputtering. The characteristics of the thin films were investigated by ellipsometry, X-ray diffraction (XRD), atomic force microscopy (AFM), photoluminescence (PL), and Hall effect. The substrate temperature and growth time were kept constant at $200^{\circ}C$ at 30 minutes, respectively. The RF power was varied within the range of 200 to 500 W. ZnO thin films on sapphire substrate were grown with a preferred C-axis orientation along the (0002) plan; X-ray diffraction peak shifted to low angles and PL emission peak was red-shifted with increasing RF power. In addition, the electrical characteristics of the carrier density and mobility decreased and the resistivity increased. In the electrical and optical properties of ZnO thin films under variation of RF power, the crystallinity improved and the roughness increased with increasing RF power due to decreased oxygen vacancies and the presence of excess zinc above the optimal range of RF power. Consequently, the crystallinity of the ZnO thin films grown on sapphire substrate was improved with RF sputtering power; however, excess Zn resulted because of the structural, electrical, and optical properties of the ZnO thin films. Thus, excess RF power will act as a factor that degrades the device characteristics.
반응표면법을 이용한 원심팬 블레이드의 고성능/저소음 최적 설계
신동휘(Donghui Shin),허승(Seung Heo),정철웅(Cheolung Cheong),김태훈(Tae-Hoon Kim),정지원(Jiwon Jung) 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.2015 No.11
In this paper, centrifugal fan blades used to circulate cold air inside a household refrigerator are optimized for high-performance/low-noise using response surface method which is frequently employed as optimization algorithm when multiple independent variables affects any dependent variable. The inlet and outet blade angles, and the inner radius are selected as independent variables. First, fan blades are optimized for the maximum the volume flow rate. Based on this result, the prototype of fan is manufactured by using 3-D printer. The measured P-Q curves confirm the increased volume flow rate of the optimized fan. Then, the rotation speed of the new fan is decreased to match the P-Q curve of the existing fan. It is found that 1.7 dBA noise reduction can be achieved by using the new fan at the same volume flow rate.
네이트온 메신저의 사용자 인증 메커니즘에 대한 취약점 분석
신동휘(Donghwi Shin),최윤성(Younsung Choi),박상준(Sangjoon Park),김승주(Seungjoo Kim),원동호(Dongho Won) 한국정보보호학회 2007 정보보호학회논문지 Vol.17 No.1
네이트온 메신저는 국내에서 가장 많은 사용자를 확보하고 있는 메신저이다. 메신저는 메일, 쪽지, 싸이월드 그리고 SMS 서비스 등의 많은 기능을 제공하고 있다. 본 논문에서는 네이트온 메신저 프로그램의 인증 트래픽을 분석하여 악의적으로 획득한 개인 인증 정보를 재전송 공격함으로써 이를 통해 공격자가 불법적으로 인증될 수 있다는 것을 설명한다. 또한 네이트온 메신저 이외에 타 국내 메신저들 또한 이와 유사한 방법으로 공격될 수 있음을 보인다. Nateon Messenger, which has the most number of users in Korea, supports many services such as E-mail, note, Cyworld, SMS, etc. In this paper, we will analyse the authentication traffic which is transmitted and received by the Nateon Messenger. Through performing the replay attack with the authentication information, we will show that an attacker can be authenticated illegally. Furthermore, we will show that other domestic messengers have similar security problems.