• 제목/요약/키워드: S2-

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B형 간염바이러스 표면항원 preS2 부위의 항원결정인자 규명 (Antigenic Determinant Mapping in preS2 Region of Hepatitis B Surface Antigen)

  • 권기선;김창수;박주상;한문희;유명희
    • 미생물학회지
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    • 제28권1호
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    • pp.13-18
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    • 1990
  • adr아형 B형 간염바이러스의 preS2유전자 부위를lacZ 유전자의 5말단에 연결하여 preS2-$\beta$-galactosidase 융합단백질을 생성하는 플라스미드, pTSZ를 건설하였다. 갈본된 preS2 유전자의 3' 및 5발단을 결손시켜 얻은 재조합 플라스미드를 발현시킨 후 결손된 preS2를 포함하는 융합단백질의 항원성을 단일클론항체 H8을 사용하여 비교하며 보았다. 양말단에서 일정부위까지의 결손은 항원성에 영향을 미치지 않았지만 그 이상의 결손에 의하여는 항윈성이 소실됨을 볼 수 있었다. 이상의 항원성 전한부위를 DNA 염기서열 분석에 의하여 결정할 수 있었다. 그 결과 항원결정인자의 양말단은 preS2 서열 중 아미노산 전기 130-132와 140→142 사이에 각각 존재함을 알 수 있었고, 아미노산 143번의 결손은 항원성의 부분적인 감소를 초래하는 것으로 보아 항원성 결정에 보충적 역할을 한다고 생각된다. 한편 adr과 adw2아형 간의 아미노산서열의 차이가 항원결정부위 중 130, 132 및 141번 위치에 존재하며 단일를론항체 H8이 adr아형에만 특이하게 결합하는 것으로 부터, 세 잔기 중 하나 혹은 그 이상이 아형특이성에 관여한다고 추정된다.

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호주에서의 ECMWF 계절내-계절 수문기상 예측치 평가 (Evaluation of ECMWF subseasonal-to-seasonal (S2S) hydrometeorological forecast across Australia)

  • 박종민
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2023년도 학술발표회
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    • pp.268-268
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    • 2023
  • 전 지구적 급격한 기후변화로 인해 수문기상인자들의 비선형적 변동성이 발생함과 동시에 가뭄, 홍수와 같은 수재해의 발생빈도 및 강도가 증가하고 있는 추세이다. 이에 따라, 세계의 유수기관 (NASA, ESA 등)에서는 대기모형과 해양 모형의 결합 및 수치해석적 접근법을 활용하여 계절내-계절 (Subseasonal to seasonal; S2S) 예측치를 생산하여 제공하고 있다. 이에 따라, 본 연구에서는 European Centre for Medium-Range Weather Forecast (ECMWF)에서 산정되는 수문기상인자 (강수량, 증발산량 및 유출량)에 대한 정확도를 평가하고자 한다. 연구지역으로는 다양한 기후대 및 토지 피복으로 구성되어 있으며, El-Nino-Southern Oscillation (ENSO), Indian Ocean Diapole (IOD)와 같은 기후 현상이 빈번히 발생하는 호주지역을 대상으로 연구를 수행하였다. ECMWF S2S 자료에 대한 통계적 검증은 1) 지점 기반 관측치와 더불어 2) 물수지 모델 기반 수문 추정치 (The Australian Water Resources Assessment Landscape Model; AWRA-L)와 비교하였다. 연구 결과 S2S 강우 및 증발산량 산정치의 경우 비교적 짧은 예측기간(약 2주)에서 상대적으로 높은 상관관계 (R=0.5~0.6)와 낮은 편차 (강수량 = 0.10 mm/day, 증발산량 = 0.21 mm/day)를 나타내었다. 유출량의 경우, 강우 및 증발산량에 비해 상대적으로 낮은 정확도를 나타내었으며, 예측 기간이 길어짐에 따라 불확실성이 상당히 높아지는 것으로 확인되었다. 이는, S2S 계산과정에서 강우 및 증발산량 뿐만아니라 지표 유출로 도달하기 전까지의 수문기상인자들의 불확실성이 모두 모여 유출량의 불확실성이 높아진 것으로 확인할 수 있었다. 계절적 검증에서는, 강우 및 증발산량 모두 여름철에 높은 상관관계를 나타내었지만 불확실성은 상대적으로 큰 값을 나타내었다. 자세한 분석을 위해, 공간적인 불확실성을 분석해본 결과 ECMWF S2S가 매우 습윤하거나 건조한 지역에서 수문기상인자를 예측하는데 있어 한계성이 나타난 것을 확인하였다. 본 연구를 토대로, 추후 S2S 예측치에 대한 보정과 더불어 미래의 수재해 발생 위험도에 대한 정보를 획득하는데 적용될 수 있을 것으로 판단된다.

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Sorghum $\times$ Sudangrass 교잡종과 간작에 의한 청예 두과작물 선발 (Selection of Legume Crop by Intercropping with Sorghum $\times$ Sudangrass Hybrid)

  • 이상무;전병태
    • 한국초지조사료학회지
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    • 제16권2호
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    • pp.93-104
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    • 1996
  • A field experiment was conducted in Chungju and Jungwon to evaluate growth characteristics, dry matter yield, protein yield and palatability of intercropping comparing with monocropping forage crops by the use of sorghum $\times$ sudangrass hybrid(S.S.H.), five forage soybeans and two forage cowpeas of superior to selected experiment of varieties. All eight treatment plots were replicated three times and cutting date were cut July 6 and September 9. 1. The mean leaf number of S.S.H. in intercropping T2 treatment showed high compared to T1 treatment in all treatment except for Hwangkeum treatment, but T3 treatment was lower than the other treatments. In the leaf number of soybean, Jangbaek treatment was the highest as 47 leaves per plant, cowpea treatments showed high above 50 leaves. The stem diameter of S.S.H. in Jangyeob treatment of T2 treatment was 9.6mm. In legume, cowpea of T3 treatment was high as ranged from 7.9mm to 8.2mm. In stem hardiness of S.S.H., TI treatment was the lower than the other treatments, while Jangbaek treatment of T2 treatment was the highest as $2.0kg/cm^2$. In legume crops, Jangbaek and Baekun treatment were the highest as $1.6kg/cm^2$, but T3 treatment was very low as $0.3~0.6kg/cm^2$. 2. In the mean leaf ratio of S.S.H., T1 treatment was higher than T2 and T3 treatment as 34.9%. In the legume crops, Togyu treatment was the highest as 40.9%. In the mean tiller number of S.S.H., T2 treatment showed high compared to TI treatment, but T3 treatment of was rather decrease than The tiller number of S.S.H. in Jangyeob treatment of T2 treatment was the highest as 4.6 per plant. The dead stubble of S.S.H. was high in order to T3>T1>T2 treatment>, T3 treatment was highly about 2 times compared to T2 treatment. 3. S.S.H. as T3 treatment was resistant to lodging, but T3 and T1 treatment showed highly lodging. In the legums, T3 treatment was resistant to lodging, but T2 treatment showed highly lodging. In the S.S.H. of T2 treatment, the leaf of summer depression was not occurrence, but T3 treatment was higher than the other treatments. 4. The palatability of domestic animals was high in order of T2>Tl>T3, especially Togyu treatment of T2 treatment was the highest at the holstein and deer, and Jangyeob treatment of T2 treatment was the highest in the Korean native cattle. But T3 treatment was lower than other treatments in the holstein and Korean native cattle. 5. Fresh yield of monocropping(T1) was the highest as 94, 650kg/ha, while dry matter yield in Jangyeob treatment of T2 treatment was the highest as 15, 575/ha But fresh yield and dry matter yield of T3 treatment were the lowest(P<0.05). 6. Protein yield in T2 treatment was high, especially Jangyeob treatment of T2 treatment was the highest as 1, 605.5 kg/ha T3 treatment was low in spite of high protein content, because dry matter yield was lower than the other treatments. In conclusion, among T1, T2 and T3 treatment, Jangyeob, Togyu and Baekun treatments of T2 treatment showed optimum varieties for intercropping with S.S.H., because they showed high Dry matter yield, protein yield and palatability.

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Micro spiral inductor를 이용한 2.5Gb/s급 2:1 Multiplexer 설계 (A 2.5Gb/s 2:1 Multiplexer Design Using Inductive Peaking in $0.18{\mu}m$ CMOS Technology)

  • 김선중;최정명;범진욱
    • 대한전자공학회논문지SD
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    • 제44권8호
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    • pp.22-29
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    • 2007
  • [ $0.18{\mu}m$ ] CMOS공정을 이용하여 supply voltage 1.8V에서 2.5Gb/s 이상의 데이터 처리속도를 가지는 2:1 Multiplexer(MUX) 설계를 하였다. High speed 동작을 위한 주파수의 한계를 극복하기 위해서 4.7 nH의 on-chip micro spiral micro inductor $(20\times20{\mu}m2)$가 설계 되었고, 10개 이상의 inductor를 사용하고도 칩 면적 증가가 거의 없으면서 inductive peaking 효과를 극대화할 수 있었다. 칩 측정은 on-wafer로 진행되었고, micro spiral inductor가 있는 2:1 MUX와 그것이 없는 2:1 MUX 각각 측정하여 그 결과를 비교하였다. 측정결과 micro spiral inductor를 가진 2:1MUX가 rise time과 fall time이 1.25Gb/s에서는 rise time이 23%, fall time은 3%의 peaking 개선 효과가 있는 것을 확인하였다. 2.5Gb/s에서는 fall time이 약 5.3%, rise time 3.5%의 개선 효과를 보았다. 전체 소비전력은 61.2mW, 2.5Gb/s에서 voltage output swing은 $180mV_{p-p}$로 측정되었다.

Deposition of $(Ti,Cr)N-MoS_2$ Thin Films by D.C Magnetron Sputtering

  • Kim S.K.;Kim J.H.
    • 한국표면공학회지
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    • 제39권2호
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    • pp.70-75
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    • 2006
  • As technology advances, there is a demand for development of hard, solid lubricant coating. (Ti,Cr)N-$MoS_2$, films were deposited on SKD 11 tool steel substrate by co-deposition of $MoS_2$, with (Ti,Cr)N using a D.C. magnetron sputtering process. The influence of the $N_2/Ar$ gas ratio, the deposition temperature, the amount of $MoS_2$ in the films, and the bias voltage on the mechanical and the structural properties of the films were investigated. Wear tests were performed on the films deposited in various conditions.

$SnO_2$-$Sb_xS_{1-x}$-Sn 구조에서의 광기전력 효과 (Photovoltaic Effects of $SnO_2$-$Sb_xS_{1-x}$-Sn Structure)

  • 박태영;김화택
    • 대한전자공학회논문지
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    • 제16권4호
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    • pp.32-35
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    • 1979
  • SnO2- amorphous Sb 5 thin film-Sn structure에서 SnO2 창으로 photon을 입사시켰을 때 photo-voltaic 효과를 발견했으며 photon의 energy에 따라 photowltage의 부호가 반전 되었다. 이러한 현상은 SnO2- Sb S 사이에서 n-n heterojunction이, Sb S Sn사이에서 schottky junction이 형성되기 때문인 것으로 여겨진다.

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인삼의 Protopanaxadiol계 사포닌으로부터 20(R)-Ginsenoside $Rh_2$ 및 20(S) 이성체의 제조 (Preparation of a 20(R)-Ginsenoside $Rh_2$ and the 20(S) Epimer from Protopanaxadiol Saponins of Panax ginseng C.A. Meyer)

  • 김신일;백남인;김동선;이유희;강규상;박종대
    • 약학회지
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    • 제35권5호
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    • pp.432-437
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    • 1991
  • A mixture of 20(R)- and 20(S)-ginsenoside Rg$_{3}$ was obtained under mild acidic hydrolysis from protopanaxadiol saponins, ginsenosides Rb$_{1}$, Rb$_{2}$, Rc and Rd. The product was acetylated to give the peracetates, which were further converted into 20(R)-ginsenoside Rg$_{3}$, 20(S)-ginsenoside Rg$_{3}$, 20(R)-ginsenoside Rh$_{2}$ and 20(S)-ginsenoside Rh$_{2}$ by the direct alkaline treatment depending upon two kinds of temperature conditions respectively. The structure and physicochemical properties of a prosapogenin, 20(R)-ginsenoside Rh$_{2}$, were investigated.

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Numerical Study on Propulsion Performance Enhancement of Superdetonative mode Ram Accelerator by using strong mixture

  • Sung, Kun-Min;Jeung, In-Seuck
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년 영문 학술대회
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    • pp.519-524
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    • 2008
  • A numerical study is conducted to investigate propulsion performance enhancement based on S225 experiment case of ISL(French-German Research Institute of Saint-Louis)'s superdetonative ram accelerator. For govern equation, multi-species Navier-Stokes equation coupled with Baldwin-Lomax turbulence modeling is used. Govern equation is discretized by Roe's FDS and integrated by LU-SGS time integration. Detailed chemical reaction about $H_2/O_2/CO_2$ for high pressure is considered. $2H_2+O_2+2.5CO_2$ mixture was used for propellant gas. For the same over-driven factor, the launching speed of computation was faster than one of S225. Another configuration and condition of S225 was applied. A flame structure is very different from S225. For strong mixture case, it shows ignition by viscous effect. Acceleration and speed increment is higher than S225 computation and experiment. By using more strong mixture, propulsion performance was enhanced.

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Effect of H2S Concentration and Sulfurization Temperature on the Properties of Cu2ZnSnS4 Thin Films

  • Arepalli, Vinaya Kumar;Kim, Eui-Tae
    • 한국재료학회지
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    • 제25권12호
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    • pp.708-712
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    • 2015
  • This study reports the effects of $H_2S$ gas concentration on the properties of $Cu_2ZnSnS_4(CZTS)$ thin films. Specifically, sulfurization process with low $H_2S$ concentrations of 0.05% and 0.1%, along with 5% $H_2S$ gas, was studied. CZTS films were directly synthesized on Mo/Si substrates by chemical bath deposition method using copper sulfate, zinc sulfate heptahydrate, tin chloride dihydrate, and sodium thiosulfate pentahydrate. Smooth CZTS films were grown on substrates at optimized chemical bath deposition condition. The CZTS films sulfurized at low $H_2S$ concentrations of 0.05 % and 0.1% showed very rough and porous film morphology, whereas the film sulfurized at 5% $H_2S$ yielded a very smooth and dense film morphology. The CZTS films were fully crystallized in kesterite crystal form when they were sulfurized at $500^{\circ}C$ for 1 h. The kesterite CZTS film showed a reasonably good room-temperature photoluminescence spectrum that peaked in a range of 1.4 eV to 1.5 eV, consistent with the optimal bandgap for CZTS solar cell applications.

고체윤활제(Graphite, MoS$_2$, Sb$_2$S$_3$)의 상대량에 따른 마찰재의 마찰 및 마모특성에 관한 연구 (Friction and Wear Characteristics of Automotive Friction Materials Containing Different Relative Amounts of Solid Lubricants(Graphite, MoS$_2$and $_2$S$_3$))

  • 최낙천;장호
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1999년도 제30회 추계학술대회
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    • pp.219-224
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    • 1999
  • The effects of solid lubricants on wear and friction characteristics of friction materials were studied using a pad-on-disk type friction tester. Friction materials with ten formulations containing different relative amounts of solid lubricants(graphite, MoS$_2$and Sb$_2$S$_3$) were investigated. Results of this work showed that each formulation with different relative amounts of the lubricants had unique friction characteristics. At low brake temperatures, friction materials containing rich graphite showed a small amount of $\mu$ change during sliding. At elevated temperatures, on the other hand, friction materials with rich Sb$_2$S$_3$and graphite showed smaller $\mu$ changes suggesting complementary lubrication of Sb$_2$S$_3$and graphite during sliding. However, the friction materials with rich Sb$_2$S$_3$showed a large amount of wear.

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