In situ 고상 에피택시 방법에 의한 CoSi₂/Si(111)구조의 형성

이정주,강민성,김현수,최치규,이운환,이종덕,이영백,김건호,이정용 濟州大學校 基礎科學硏究所 1996 基礎科學硏究 Vol.9 No.2

초고진공에서 공상에피택시(solid-phase epiyaxy, SPE) 방법으로 CoSi₂를 Si(111)기판 위에 에피택시 성장시켰다. 2MeV⁴He++ ion후방산란 분광기와 사중결정 x-선 회절기 및 고분해 투과전자 현미경을 이용하여 성장된 CoSi₂의 상과 조성, 결정성, 그리고 계면의 미시구조를 조사하였다. 초고진공상태의 실온에서 Si(111)-7X7기판에 Co를 약 20 ~50 ?? 중착한 후 SPE에 의하여 실리사이드를 형성시키는 경우 600℃에서는 B-형의 CoSi₂가, 그리고 700℃에서는 A형의 CoSi₂가 선택적으로 에피택시 성장하였으며, 정합성은 B-CoSi₂[110]//Si[110] and CoSi₂(111)//Si(111)이, 그리고 700℃에서는 A-CoSi₂[110]//Si[110], CoSi₂(002)//Si(002)을 나타내었다. Epitaxial films of CoSi₂were grown on Si(111) substrates by in situ solid-phase epitaxy in a ultrahigh vacuum. The phase, the chemical composition, the crystallinity, and the microstructure of the Silicide/Si interface were investigated by 2-MeV⁴He++ ion-backscattering spectrometry, quadruple crystal X-ray diffractometry, and high-resolution transmission eletron micorscopy. High-quality films of either B-type or A-type CoSi₂ could be grown selectively on Si(111) substrates by depositing ~ 20 ~ 50 ?? of Co on a Si(111)-7X7 substrate followed by in situ annealing at 600℃ or 700℃ for 10 min. The matching face relationships are CoSi₂[110]//Si[110] and CoSi₂(111)//Si(111) by B-type CoSi₂ and CoSi₂[110]//Si[110]//Si[110] and CoSi₂(002)//Si(002) for A-type CoSi₂.

Light-extraction efficiency control in AlGaN-based deep-ultraviolet flip-chip light-emitting diodes: a comparison to InGaN-based visible flip-chip light-emitting diodes.

Lee, Keon Hwa,Park, Hyun Jung,Kim, Seung Hwan,Asadirad, Mojtaba,Moon, Yong-Tae,Kwak, Joon Seop,Ryou, Jae-Hyun Optical Society of America 2015 Optics express Vol.23 No.16

<P>We study light-extraction efficiency (LEE) of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) using flip-chip (FC) devices with varied thickness in remaining sapphire substrate by experimental output power measurement and computational methods using 3-dimensional finite-difference time-domain (3D-FDTD) and Monte Carlo ray-tracing simulations. Light-output power of DUV-FCLEDs compared at a current of 20 mA increases with thicker sapphire, showing higher LEE for an LED with 250-관m-thick sapphire by ~39% than that with 100-관m-thick sapphire. In contrast, LEEs of visible FCLEDs show only marginal improvement with increasing sapphire thickness, that is, ~6% improvement for an LED with 250-관m-thick sapphire. 3D-FDTD simulation reveals a mechanism of enhanced light extraction with various sidewall roughness and thickness in sapphire substrates. Ray tracing simulation examines the light propagation behavior of DUV-FCLED structures. The enhanced output power and higher LEE strongly depends on the sidewall roughness of the sapphire substrate rather than thickness itself. The thickness starts playing a role only when the sapphire sidewalls become rough. The roughened surface of sapphire sidewall during chip-separation process is critical for TM-polarized photons from AlGaN quantum wells to escape in lateral directions before they are absorbed by p-GaN and Au-metal. Furthermore, the ray tracing results show a reasonably good agreement with the experimental result of the LEE.</P>

가토 외고정 모델을 이용한 치밀체형 세라믹스의 골결합능 평가

이재협,이동호,이재학,공현식,안영준,류현승,서준혁,홍국선,김환,장봉순,이춘기 대한정형외과연구학회 2003 대한정형외과연구학회지 Vol.6 No.2

Slide Session : OS-IFD-07 ; Infectious Disease : In Vitro Antiviral Activity of Ribavirin Against Severe Fever with Thrombocytopenia Syndrome Virus

( Myung Jin Lee ),( Kye Hyung Kim ),( Jong Youn Yi ),( Su Jin Choi ),( Chung Jong Kim ),( Nak Hyun Kim ),( Kyoung Ho Song ),( Pyoeng Gyun Choi ),( Ji Hwan Bang ),( Wan Beom Park ),( Eu Suk Kim ),( San 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

In Vitro Antiviral Activity of Ribavirin Against Severe Fever with Thrombocytopenia Syndrome Virus Myung Jin LEE1, Kye-Hyung KIM1, Jongyoun YI2, SuJin CHOI1, Chung-Jong KIM1, Nak- Hyun KIM1, Kyoung-Ho SONG1, Pyoeng Gyun CHOI1, Ji-Hwan BANG1, Wan Beom PARK1, Eu Suk KIM1, Sang-Won PARK1, Hong Bin KIM1, Nam Joong KIM1, Myoung- Don OH1 Seoul National University College of Medicine, Korea1, Pusan National University School of Medicine, Korea2 Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by a novel Bunyavirus, severe fever with thrombocytopenia syndrome virus (SFTSV). No effective antiviral therapy is proven yet, but clinical use of ribavirin (RBV) has been tried. We investigated the antiviral effect of RBV against SFTSV in vitro. Methods: To test for cytotoxicity of RBV, Vero cells were treated with different concentrations of RBV (3.90 to 500 μg/mL, two-fold dilution) and analyzed by cell viability MTS assay 48h post-infection. To determine antiviral activity of RBV against SFTSV, Vero cells were infected with SFTSV strain Gangwon/Korea/2012 at 100 TCID50 (50% tissue culture infective dose) per well in a 96-well plate, and RBV was added at the concentrations showing no or minimal cytotoxicity. Viral RNAs were extracted from the culture supernatants and quantifi ed using one-step real-time reverse transcription- PCR to amplify the partial large segment of SFTSV. Statistical analysis was done by one-way ANOVA with Tukey`s post hoc test. Results: Cytotoxicity due to RBV was not observed at RBV concentration =31.3 μg/ mL. Viral RNAs at 24h post-RBV treatment were reduced with increasing RBV concentrations (1-32 μg/mL), compared with those of mock-treated cells (P <0.01, Figure). Half maximal inhibitory concentration (IC50) of RBV was 3.69 μg/mL at 24h post-RBV treatment. Conclusions: Our study shows that RBV has antiviral effect against SFTSV in a dose-dependent manner. Further studies are required to evaluate the effi cacy of RBV in SFTS.

An Investigation on the Life of Master Won Guk Lee, the Creator of Chung-Do-Kwan

( Seon Young Jung ),( Jun Ho Lee ),( Seung Woo Shin ),( Chun Hwan Cho ),( Seung Hyun Jang ),( Won Shin ) 경남대학교 기초과학연구소 2014 기초과학지 Vol.31 No.-

The purpose of this study is to review (or, investigate) the life of Won Guk Lee. He is the creator of Chung-Do-Kwan, which is one of the five original Taekwondo kwans. Data was gathered from advanced research, newspapers, documentaries, the Internet, magazines, and journals etc. Thus, we were able to create a sequence of events based on the research data. First, we can say that in Won Guk Lee``s career, he created Chung-Do-Kwan and brought Dangsoodo to Korea. These events have had a significant development on Taekwondo. Second, Taekwondo curriculum, which was published by Won Guk Lee, established the foundation of Taekwondo poomsae, as well as giving us the pure spirit of Korean martial arts.

비대칭 안모의 치험 2례

현용휴,설인택,김영균,여환호,이철우 大韓顎顔面成形再建外科學會 1992 Maxillofacial Plastic Reconstructive Surgery Vol.14 No.4

Facial asymmetry can be most distressing for the young child and parents. It can cause functional problems as a result of malocclusion. Classification of facial asymmetry has not been yet well-organized because of its varieties on etiologic factors, involved sites and clinical expressions. Even though, we don’t know its causes definitely. It is generally believed that problems with aberrant pattern of condylar growth are related to facial asymmetry. This is a case report on surgical correction of the patients who had severe facial asymmetry. One patient was diagnosed as condylar hyperplasia and the other was diagnosed as a condylar hypoplasia related to trauma. We performed a simultaneous two-jaw surgery, condylar shaving, inferior border ostectomy of affected mandible in the former case, and a simultaneous two-jaw surgery, reverse-L osteotomy and alloplastic implantation with Biocoral in the latter case. The postoperative results of the two cases were excellent functionally and esthetically.

中性시스템에서 白水의 再循還과 脫水 條件이 內添 藥品의 擧動에 미치는 影響

이은정,김병수,정현채,김철환,박종열 경상대학교 농업생명과학연구원 2003 농업생명과학연구 Vol.37 No.4

중성 초지에서 공정의 최적화를 위해 사용되는 각종 첨가제로 인해 백수 시스템은 산성 초지보다 훨씬 복잡한 특성을 나타내고 있다. 특히, 환경 및 경제적 이유로 공정수의 완전한 재사용을 위한 노력이 계속되고 있으며, 백수의 재사용은 제지 공정에 있어서 원료의 절감과 폐수의 부하를 줄일 수 있는 잇점이 있기 때문에 지속적인 연구가 이루어지고 있다. 그러나 초지 공정에서 배출되는 백수는 각 위치에 따라 그 특성이 다름에도 불구하고 통합되어 관리되고 있다. 따라서 본 연구에서는 백수의 재순환 회수와 탈수부 압력을 달리 했을 때 탈수부의 위치와 조건에 따른 백수의 유기 성분, 무기 성분과 수질 특성 그리고 이들 조건이 미세분 보류도와 종이의 특성에 미치는 영향을 파악한 결과 다음과 같은 결론을 얻었다. ① 백수의 재순환과 탈수부 조건에 따른 유기 및 무기 성분에 대하여 각각 FTIR과 WRD를 사용한 결과, 제지 공법에 사용되는 각종 물질의 추적을 위해 효과적인 방법으로 판단 되었다. ② 백수의 재순환 회수와 탈수 압력에 따른 수질 분석 결과 자연 탈수부에서는 백수의 재순환 회수가 증가할수록 무기염, 탁도, COD는 증가하였으며 진공 탈수부에서 보다 무기염, 탁도 및 COD는 낮은 것으로 나타났다. ③ 백수의 재순환 회수와 탈수 압력에 따른 종이의 강도적 특성과 미세분 보류도의 결과를 비교한 결과 이들간에 밀접한 관련이 있었다. ④ 백수의 재순환 회수에 따른 자연 탈수부와 진공 탈수부에서 탈수 조건에 따라 백수의 특성이 달라진다는 것을 알 수 있었다. 특히 무기염의 함유량, 탁도, COD 그리고 양이온 요구도에 있어서 자연 탈수부와 진공 탈수부 조건 사이에 나타난 결과에 따라 자연 탈수부에서 수집된 백수는 진공 탈수부에서 수집된 백수보다 미세분, 섬유, 충전제 및 기타 첨가제들을 많이 함유하고 있었으므로 탈수조건에 따라 백수의 이원화 관리가 필요한 것으로 판단된다. There has been shown more complicate characteristics of white water in the alkaline paper making system than that of acid paper making system. Because the alkaline wet end system is consisted with various functional chemicals to control optimum one pass retention on the wire part and chemi-mechanical properties of final paper, especially perfect reuse of white water due to environmental economical view point has been performed. However, in the paper making system, discharged white water in different position and physical conditions to remove in wet web is managed in same line. Therefore, this reserch was performed to identify organic, inorganic material in white water and water recycling and vacuum intensity on the chemical characteristics in the water and properties the paper. The results obtained are summarized as follow: 1. FTIR and XRD which were used for identifying wet end chemical were effective instrument to chase the chemicals from wet end stock to white water.88 2. According to control white water recycle number and vacuum intensity, the characteristics of white water were changed. 3. In condition of atmospheric pressure, apparent amount of fines and several chemicals which produce environmental problom was higher than that of high vaccum condition. 4. Paper mill has to control the white water differently on condition of vacuum and to separate from white water discharged in atmospheric pressure and high vacuum intensity 5. It can be very effective white water management to reduce water pollution and to improve runnability.

QFT를 이용한 전력 계통 안정화 장치 설계

이정필,정현화,김창현,정형환 동아대학교 정보기술연구소 2001 情報通信硏究所論文誌 Vol.8 No.2

In this paper, QFT robust control strategy is proposed to improve stability of power systems in the presence of parametric uncertainty. The basic idea in QFT is to convert design specifications of a closed loop system and plant uncertainties into robust stability and performance bounds on the open loop transmission of the nominal system and then to design a controller by using the gain-phase loop shaping technique. The robustness of the QFT controller has been investigated on a single machine infinite bus model by nonlinear simulations.

신경회로망에 웨이브렛 함수를 이용한 새로운 지능제어방식

이용구,이승형,이현관,엄기환 동국대학교 대학원 1997 大學院硏究論集-東國大學校 大學院 Vol.27 No.-

In this paper, we propose the hybrid system identification model and control method using neural networks. Proposed control method performs, for a nonlinear plant with unknown functions, system identification using an adaptive wavelet in a neural network, and then a nonlinear controller is designed with those identified informations. To identify a nonlinear function, which is not directly related to input signals, we can use an adaptive wavelet in three-layed neural network. In order to verify the usefulness of the proposed method, we simulate the proposed control method with cart pole system.

Equisetum arvense L.이 고혈당 쥐의 혈중 포도당 농도에 미치는 영향

이현자,김석환,손기호,강우규,최종원 慶星大學校 環境問題硏究所 1992 環境硏報 Vol.2 No.1

The effect of methanol extract of Equisetum arvense L.(EM) on blood glucose level in streptozotocin-induced diabetic rat and acute toxicity of EM were investigated. Male Sprague-Dawley rats(200∼250g), with free access to commercial rat chow and water, were divided into four groups: Group 1 served as control; Group 2 received STZ only: Group 3 received EM only; Group 4 received pretreatment with EM followed by STZ administration. EM did not affect the normal blood glucose level and LD50 was about 6,250㎎/㎏. EM pretreatment in STZ-induced diabetic rats slightly inhibited Weight loss and water consumption. EM pretreatment in STZ-induced diabetic rats slightly inhibited the rise of serum glucose concentration. Serum transaminase(AST, ALT) and sorbitol dehydrogenase(SDH) were slightly increased by STZ induced changes in the serum glucose level.