http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
능동 궤환을 이용한 0.5 ~ 3 GHz 광대역 구동 증폭기 설계 및 제작
임준형,남정우,장승호,김창우 慶熙大學校 레이저 工學硏究所 2003 레이저공학 Vol.14 No.-
A wideband SiGe HBT driver amplifier has been developed for multimode mobile terminal applications. The amplifier has been designed with an active feedback scheme to have good VSWRs and gain flatness in 0.5 ~ 3 GHz band. The active feedback circuit acts as a shunt feedback circuit, which uses the collector-emitter conductance controlled by the base-emitter voltage. The amplifier has been fabricated on FR-4 board with multichip components. At an optimal tuning condition, the amplifier exhibits a power gain of 13 dB, 10-dB input/output return loss, and 10-dBm 1-dB compression output power in 0.5 ~ 3 GHz band. The ACPR characteristics of the amplifier are -52.1 dBc at cellular band (@ 1.98 MHz offset bands) and -48.3 dBc at IMT-2000 band (@ 5 MHz offset bands).
尹世重,李聖瑞,徐廷穆,崔鎬亨,蘇鮮燮 공주대학교 사범대학 과학교육연구소 1984 과학교육연구 Vol.16 No.1
師範大學의 生物 實驗 敎育의 改善 方向을 강구하기 위하여 전국 15개 師範大學의 生物敎育科에서 敎育하고 있는 실험 실습을 학점을 중심으로 조사하였고 아울러 20개 非師範系 대학의 생물 실험실습 학점도 조사하여 비교하고, 분석 하므로서 다음과 같은 몇 가지 결과를 얻게 되었다. 1) 師範系 生物 敎育科의 전공 학과중 實驗 實習 배정시간 및 학점수를 늘려 나가야 하겠다. 2) 探究學習 지도 能力을 保有할 수 있도록 實驗 實習 指導 改善 方法을 강구해야겠다. 3) 基礎 共通科目은 3과목 모두를 최소한 1학기는 이수토록 해야 하고 반드시 실험 실습을 竝行 하여야 하겠다. A study for the model of the laboratory experiment curriculum in teacher's college seience was done. Because of individual characteristics in each field in department sc-ience education, the model was not necessarily unique. However, the common elements of frame in this model were suggested as follows : 1. The ratio of laboratory experiment's credits and total major credits. 2. The ratio of basic common laboratory experiment's credits (basic physics, basic chemistry, basic biology, and basic earth science) and total laboratory experiment's credits. 3. Credits and course name of laboratory experiments charactoristic for the science education in teacher's college. 4. Suggestion of the experimental guide for an inquiry learning.
Jung, Seun-Ho,Kim, Hyun-Won Korean Society for Biochemistry and Molecular Biol 1998 Journal of biochemistry and molecular biology Vol.31 No.1
Asymmetry amongst nucleotide binding sites of Escherichia coli $F_1$-ATPase was examined using $^{19}F$ NMR signal from fluorinated analogs of adenine nucleotides bound to nucleotide binding sites. ADP-$CF_2-{PO_3}^{2-}$ showed no inhibitory effect to $F_1$-ATPase. But ADP-CHF-${PO_3}^{2-}$ (racemic mixture) showed competitive inhibition of $F_1$-ATPase with $K_i$ of $60\;{\mu}m$. ADP-CHF-${PO_3}^{2-}$ shows only negligible binding to $EF_1$ in the absence of $Mg^2+$. With the addition of $Mg^2+$ to the medium, the $^{19}F$ resonance of free ADP-CHF-${PO_3}^{2-}$ disappeared and the new broad resonances appeared. Appearance of more than two new asymmetric resonances following the binding of ADP-CHF-${PO_3}^{2-}$ to $EF_1$ may indicate that at least one of the isomers showed split resonances. This may suggest that the region between ${\alpha}$-and ${\beta}$-phosphate of ADP-CHF-${PO_3}^{2-}$ which is bound to catalytic sites is experiencing a different environment at different sites.
Jung, Eun-Kyoung,Jeong, Karp-Joo,Lee, Sang-San,Kim, Jee-In,Jung, Seun-Ho Korean Chemical Society 2003 Bulletin of the Korean Chemical Society Vol.24 No.11
Molecular modeling was performed to comprehend the chiral recognition of ${\alpha}$-methoxy-${\alpha}$-trifluoromethylphenylacetic acid (MTPA) enantiomers by cyclomaltoheptaose (${\beta}$-cyclodextrin,${\beta}$-CD) and 6-amino-6-deoxy-cyclomaltoheptaose (am-${\beta}$-CD). Monte Carlo (MC) docking coupled to constant temperature molecular dynamics (MD) simulations was applied to the investigation for the ${\alpha}$-methoxy-${\alpha}$-trifluoromethylphenylacetic acid complexation with two different CDs in terms of the relative distribution of the interaction energies. The calculated results are finely correlated with the experimental observations in chiral recognition thermodynamics. Am-${\beta}$-CD as a host showed the superior enantio-discrimination ability to the native ${\beta}$-CD where the amino group of am-${\beta}$-CD was critically involved in enhancing the ability of chiral discrimination via the Coulombic interaction with MTPA.