• Title/Summary/Keyword: S/R

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Measuring the Capabilities of R & D Personnel : ETRI Case (연구인력의 능력지수 개발 및 측정 사례연구 : 한국전자통신연구원 사례를 중심으로)

  • 유진호;배문식;백의선
    • Journal of Korea Technology Innovation Society
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    • v.1 no.2
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    • pp.220-230
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    • 1998
  • Recent concerns over national and corporate competitiveness have stimulated a renewed interest in organization's performance. The organization's performance primarily depends on resources including human resources, budget, physical based resources, and so on. Especially because the relationship between organization's performance ;md individual capabilities is more evident in R & D organizations where the knowledge base is embodied in people, there has taken an increasing interest in the methodologies for measuring the capabilities of R & D personnel. This paper presents new methodological approach to measure the capabilities of R & D personnel. And the model is empirically applied to ETRI, a public R & D organization in Korea. On the basis of the results, the implications for R & D management are discussed, with regard to R & D business and human resources management.

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NONADDITIVE STRONG COMMUTATIVITY PRESERVING DERIVATIONS AND ENDOMORPHISMS

  • Zhang, Wei;Xu, Xiaowei
    • Bulletin of the Korean Mathematical Society
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    • v.51 no.4
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    • pp.1127-1133
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    • 2014
  • Let S be a nonempty subset of a ring R. A map $f:R{\rightarrow}R$ is called strong commutativity preserving on S if [f(x), f(y)] = [x, y] for all $x,y{\in}S$, where the symbol [x, y] denotes xy - yx. Bell and Daif proved that if a derivation D of a semiprime ring R is strong commutativity preserving on a nonzero right ideal ${\rho}$ of R, then ${\rho}{\subseteq}Z$, the center of R. Also they proved that if an endomorphism T of a semiprime ring R is strong commutativity preserving on a nonzero two-sided ideal I of R and not identity on the ideal $I{\cup}T^{-1}(I)$, then R contains a nonzero central ideal. This short note shows that the conclusions of Bell and Daif are also true without the additivity of the derivation D and the endomorphism T.

NOTES ON SYMMETRIC SKEW n-DERIVATION IN RINGS

  • Koc, Emine;Rehman, Nadeem ur
    • Communications of the Korean Mathematical Society
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    • v.33 no.4
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    • pp.1113-1121
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    • 2018
  • Let R be a prime ring (or semiprime ring) with center Z(R), I a nonzero ideal of R, T an automorphism of $R,S:R^n{\rightarrow}R$ be a symmetric skew n-derivation associated with the automorphism T and ${\Delta}$ is the trace of S. In this paper, we shall prove that S($x_1,{\ldots},x_n$) = 0 for all $x_1,{\ldots},x_n{\in}R$ if any one of the following holds: i) ${\Delta}(x)=0$, ii) [${\Delta}(x),T(x)]=0$ for all $x{\in}I$. Moreover, we prove that if $[{\Delta}(x),T(x)]{\in}Z(R)$ for all $x{\in}I$, then R is a commutative ring.

Sequence Analysis and Functional Expression of the Structural and ]Regulatory Genes for Pyruvate Dehydrogenase

  • Hwan Youn;Jangyul Kwak
    • Journal of Microbiology
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    • v.40 no.1
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    • pp.43-50
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    • 2002
  • A cluster of genes encoding the pyruvate dehydrogenase complex (PDC) of Streptomyces seoulensis, a Gram-positive bacterium, was cloned and sequenced. The genes of S. seoulensis consist of four open reading frames. The first gene, lpd, which encodes a lipoamide dehydrogenase, is followed by pdhB encoding a dihydrolipoamide acetyltransferase (E2p), pdhR, a regulatory gene, and pdhA encoding a pyruvate dehydrogenase component (Elp). Elp had an unusual homodimeric subunit, which has been known only in Gram-negative bacteria S. seoulensis E2p contains two lipoyl domains like those of humans and Streptomyces faecalis. The pdhR gene appears to be clustered with the structural genes of S. seoulensis PDC. The PdhR-overexpressed S. seoulensis howed growth retardation and the decrease of Elp, indicating that PdhR regulates the function of PDC by repressing the expression of Elp. A strain of Streptomyces licidans overexpressing S. seoulensis PdhR showed a significant decreasein the level of actinorhodin, implying a regulatory role for Streptomyces PDC in antibiotic biosynthesis.

IGBT VVVF INVERTER AS A PROPULSION SYSTEM FOR ELECTRIC CAR (전동차 견인용 IGBT VVVF 인버터)

  • Chung, E.S.;Park, Y.H.;Jang, K.H.;Lee, S.J.;Bae, B.H.;Kim, J.S.;Kim, S.H.
    • Proceedings of the KIEE Conference
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    • 1997.07a
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    • pp.373-375
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    • 1997
  • In this paper, we present IGBT VVVF inverters as a 1C1M propulsion system for electric car. These inverters are composed of high power IGBT's and controlled by compact control units. The control unit performs full digital control by using 32bit DSP and microcontroller. By using CAN-bus, high speed network is constructed within four control units. The stack is simplified and optimized by using plate bus and IGBT driver units of hybrid-type.

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FUZZY CONTROL SYSTEM in PLC (PLC에서의 FUZZY CONTROL SYSTEM의 구현)

  • Lee, Y.J.;Ryou, J.S.;Song, S.W.;Park, S.B.;Hong, J.S.
    • Proceedings of the KIEE Conference
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    • 1995.07b
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    • pp.895-897
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    • 1995
  • As PLC has become cetral to today's FA environment, the importance of developing and providing special-unit of PLC such as Analog-unit, PID-unit, Fuzzy-unit has increased. In this paper introduce the Fuzzy-unit which is developed by LGIS R&D lab, and presents availability of PLC-control system with fuzzy-unit.

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Analysis of Higher Order Structure of 5S rRNA from Xanthomonas celebensis by Using Angiogenin (안지오제닌을 이용한 Xanthomonas celebensis 5S rRNA의 고차원 구조 분석)

  • Kim, Sang Beom;Jo, Bong Rae;Im, Ja Hye;Jang, Su Ik;Park, In Won
    • Journal of the Korean Chemical Society
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    • v.38 no.10
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    • pp.769-773
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    • 1994
  • Higher order structure of 5S rRNA isolated from Xanthomonas celebensis was examined using angiogenic extracted from milk. Angiogenin cleaved exclusively 3' P-O bonds on the far sides of pyrimidines in the single-stranded sequences of 5S rRNA. Whereas angiogenin acted only on the loop d of 5S rRNA at pH 7.0 in the presence of 10 mM $Mg^{2+}$, it acted on all the loops (a, b, c and d) except loop e in the absence of $Mg^{2+}$. In the absence of $Mg^{2+}$, bonds $U_{74}$-$G_{75}$, $U_{77}$-$A_{78}$ and $U_{103}$-$A_{104}$ were highly susceptible to the action of angiogenin both at pH 7.0 and at pH 3.5. On the other hand, at pH 3.5 in the absence of $Mg^{2+}$ angiogenin strongly cleaved the bond $C_{17}$-$G_{18}$ of loop a and the bond $U_{55}$-$G_{56}$ of loop b. The results lead us to the following conclusion. First, angiogenin can be used as one of the probes for the tertiary structure analysis of 5S rRNA. Second, the structure of loop d of 5S rRNA is variable depending on the concentrations of $Mg^{2+}$ and $H^{1+}$.

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The Evaporation Flow Patterns and Heat Transfers of R-22 and R-134a in Small Diameter Tubes (세관내 R-22 and R-134a의 증발 유동양식과 열전달)

  • Son, Chang-Hyo
    • Journal of Hydrogen and New Energy
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    • v.18 no.3
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    • pp.275-283
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    • 2007
  • 본 논문은 세관(ID<7 mm) 내 R-22와 R-134a의 증발 열전달과 유동양식에 대한 실험적 연구이다. R-22와 R-134a의 유동양식을 관찰하기 위해 내경 2와 8 mm의 파이렉스 튜브를 사용하였고, 열전달 계수는 내경 1.77, 3.35, 5.35 mm의 수평 평활동관에 대해서 측정하였다. 증발 유동양식에서 내경 2 mm의 환상류 영역이 내경 8 mm에 비해 저건도 영역에서 발생하는 것을 확인할 수 있었고, 내경 2 mm의 유동양식은 Mandhane의 선도와 많은 오차를 보였다. 세관(ID<7 mm) 내 증발 열전달 계수는 종래의 대구경관(ID>7 mm)에 비해 관직경에 대한 영향이 많이 나타나는 것을 알 수 있었다. 내경 1.77 mm의 열전달 계수는 내경 3.36 mm와 5.35 mm에 비해서 20내지 30% 정도 높은 것을 나타났다. 또한 종래의 열전달 상관식(Shah's, Jung's, Kandlikar's and Oh-Katsuda's correlation)과 비교한 결과, 실험 데이터는 상관식과 많은 이탈 정도를 보였다. 따라서 실험데이타를 기초로 세관내 R-22와 R-134a에 적용할 수 있는 증발 열전달 상관식을 새로이 제안하였다.

In vitro Antibacterial Activity of DWP20418, a New Carbapenem Antibiotic (새로운 카바페넴계 항생물질인 DWP20418의 In vitro 항균작용)

  • Kim, Ji-Yeon;Choi, Moon-Jung;Park, Nam-Joon;Yim, Seong-Soo;Byun, Young-Seok;Yu, Young-Hyo;Park, Myung-Hwan
    • YAKHAK HOEJI
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    • v.41 no.2
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    • pp.233-240
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    • 1997
  • The in vitro antibacterial activity of DWP20418 (1R, 5S, 6S)-6-[1-(R)-Hydroxyethyl)-l-methyl-2-[(2S,4S)-2-(piperazinylcarbonyl)-1-(R)-hydroxyethyl)pyrrolidine-4-thio]carb apen-2-em-3-carboxylic acid), a new carbapenem antibiotic, was compared with those of imipenem (IPM) and meropenem (MEPM). DWP20418 was comparable or slightly more superior to MEPM against gram-positive bacteria, and it showed more potent activity to IPM against gram-negative bacteria. DWP20418 was particularly active against MRSA, and its $MIC_{90}$ of methicillin-susceptible S. aureus, low methicillin-resistant S. aureus and high methicillin-resistant S. aureus were 0.391, 25 and 50 ${\mu}g/ml$, respectively. With a view of $MIC_{90}$, DWP20418 was comparable than the other carbapenems against P. aeruginosa and E. coli isolates. The activity of DWP20418 was not affected in the presence of $Mg^{2+},\;Ca^{2+}$ or horse serum. But inoculum size and alterations in pH of medium affected its antibacterial activity. DWP20418 showed rapidly bactericidal activity within 1h, and regrowth was not observed even incubation of 24hrs at the concentrations near the MIC.

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