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

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>

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.

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.

Equisetum arvense L.이 Streptozotocin유발 당뇨성 쥐의 항당뇨작용에 미치는 영향

이현자,김석환,손기호,최종원 慶星大學校 環境問題硏究所 1993 環境硏報 Vol.3 No.1

The present study was undertaken in order to elucidate the effects of pretreatment with Equisetum arvense L.(EM) on change in serum lipid compositions and pancreatic enzymes induced by streptozotocin(STZ) in rats with pancreatic histopathology. 1. Total serum lipid and triglyceride levels in the STZ-induced diabetic rats were significantly higher than those in the control group, and those in the group pretreated with EM but the phopholipid serum level was not significantly different in any of the group. 2. In the STZ-induced diabetic group, the total serum cholesterol, VLDL-and LDL-cholesterol levels, and the atheroscerotic index were higher, while the HDL-cholesterol level was lower when compared to the control group. HOwever, these changes were slightly prevented by EM. 3. Pancreatic lipase and trypsin activities were increased, but amylase activity was decreased by STZ, and pretreatment with EM slightly prevented these STZ-induced changes, in the histological changes of the pancreatic β-cell. These results suggest that EM pretreatment slightly supresses STZ induced changes in the serum lipid compositions and pancreatic enzyme via maintenance of prevent of β-cell destruction by STZ.

실험적으로 유도된 이독성 난청에서의 Ginkgo Extract의 효과

이상흔,조영채,도현우,강현욱,조태환 경북대학교 병원 1997 경북대학교병원의학연구소논문집 Vol.1 No.1

이독성 난청에서의 Ginkgo extract의 효과를 보고자 기닉픽 22마리를 대상으로 이음향방사를 측정하여 난청군과 치료군을 비교 검토한 바 성적을 요약하면 다음과 같다. 난청군에서의 DP-OAE는 대군조에 비해 전 주파수에서 감소 내지 소실을 보였으며4KHz 에서만 선택적으로 큰 감소를 나타낸것도 있었다. Ginkgo estract로 예방 치료한 군에서는 난청군에 비해 DP-OAE가 현저하게 출현 하였으며 정상 DP-OAE소견을 나타낸 것도 있었다. 난청치료군에서도 난청군에 비해 전체적으로 DP-OAE 가높게 출현되고 있었다. 이상의 소견으로 보아 Ginkgo estract가 이독성 난청과 감각신경성 난청에서의 예방 및 치료 효과의 가능성을 제시해 준다고 생각되는 바이다. This study was designed to investigate the effect of Ginkgo biloba extract on the kanamycin induced ototxicity in inner ears 22 guinea pigs. The animals were divied into 4 groups. In ototoxic group, kanamycin was injected 400mg/kg per day for 7 to 10 days. In preventive treated group, kanamycin with same dose and Ginkgo biloba extract(50mg/kg)were simultaneously injected daily for same duration. In post treated toup, Ginkgo extract was treated for 15 days in kanamycin injected group. The Preyer's reflex and DP-OAE (distortion product otoacoustic emissions) were used for the monitoring of hearing changes. In the ototoxic group, the amplitude of DP-OAE was marked decreased or disappeared in all test frequencies or 4KHz only. The Preyer's reflex was disappeared in all ototoxic group. In the preventive treated group with Ginkgo extract, normal DP-OAE or slightly decreased DP-OAE in 4 KHz was noticed. This finding was seemed to be similar to the post-treated group. From the above results, Ginkgo extract is suggested to have beneficial effects for the management of ototoxicity and sensorineural hearing loss.

런닝머신 프레임의 구조해석

이종선,김세환,이현곤 호서대학교 반도체제조장비국산화연구센터 2000 학술대회 자료집 Vol.2000 No.1

This study is object to structural analysis of running machine frame. The finite element model was developed to compute the stress, strain and natural frequency for running machine frame. For structural analysis using result from FEM Code. In other to structural analysis of running machine frame, many variables such as load condition, boundary condition and weight condition are considered.

비행청소년의 식생활태도와 식이자기효능감에 관한 연구

이정숙,이현자,송병춘,김은경,이춘복,김석환 대한지역사회영양학회 2008 대한지역사회영양학회지 Vol.13 No.5

The purpose of this study was to identify the factors associated with dietary attitudes and dietary self-efficacy of juvenile delinquents. Out of 110 questionnaires distributed to the juvenile detention home students in Daegu, and 150 questionnaires distributed to the juvenile detention home students in Anyang, 210 were analyzed (80.7% analysis rate). These data were analyzed by SPSS program. The results are summarized as follows. Almost all parents’ educational levels showed ‘graduation of middle school’, and only 43.8% of the juvenile detention students were living with parents. In case of incoming status, average income per month was 2,000,000 won, which was lower than normal one. Diet attitude score was higher in boy students than girl students (p < 0.05). There was a higher score of diet attitude in higher educational levels of father. The average score of dietary self-efficacy was 2.51 ± 0.86. This value was lower than the normal juvenile. There was a higher diet attitude score in the higher dietary self-efficacy score (p < 0.001). Therefore, proper nutrition education is required to improve their dietary self-efficacy. The results of this study could be useful data to plan and develop nutritional education programs of juvenile delinquents.

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.