• Title/Summary/Keyword: Gem

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The study on the vibration characteristic of IPM motor according to the notch design (Notch 설계에 따른 매입형영구자석형 전동기의 진동특성 고찰)

  • Lee, Seung-Hoon;Ahn, Ho-Jin;Kang, Gyu-Hong;Jang, Ki-Bong;Kim, Gyu-Tak
    • Proceedings of the KIEE Conference
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    • 2008.10c
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    • pp.47-49
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    • 2008
  • This paper presents the vibration characteristic of interior type permanent magnet (IPM) motor according to rotor design. In the design methods, the optimal notchs are put on the rotor pole face, which have an effect on variation of permanent magnet (PM) shape or residual flux density of PM. Through the space harmonics field analysis, the positions of notch are found and the optimal shapes of notch are decided by using Finite Element Method (FEM). The validity of the proposed method is confirmed with experiments. Therefore, the vibration, starting current and efficiency of IPM is measured by experiment.

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토양환경에서 transformation 에 의한 유전물질의 전이

  • 이건형
    • The Microorganisms and Industry
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    • v.16 no.1
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    • pp.18-20
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    • 1990
  • 현재 전세계적으로 10,000여개 이상의 실험실에서 생물공학적인 연구가 진행중에 있고, 200여개 이상의 회사에서 생물공학을 이용한 제품이 만들어지고 있다.(Saftlas, 1984). 이와같은 제품으로 생물농약(예, 모기억제에 사용되는 Bacillus thuringiensis var. israelensis 등)이라든가 insulin, 성장호르몬, lymphotoxin및 항암제등의 의약품(Saftlas, 1984)과 식물품종개량제(예, 질소 공정의 vector로 사용되는 Agrobacterium tumerfaciens의 Ti Plasmid)(McDanial, 1981 ; Shaw, 1986) 등이 있다. 그러나 최근 미생물 생태분야에서는 이와같이 만들어진 미생물들 (genetically engineered microorganisms : GEMs)이 자연 생태계에 유출되었을때 야기될 가능성이 있는 biohazaed에 대하여 관심이 집중되고 있다. (Curtiss, 1976 ; Sharples, 1983 ; Rissler, 1984). 토양환경에서 GEM이 유전물질을 전달항 수 있는 기작은 크게 conjugation, transduction, transformation 등이 알려지고 있다. 여기서는 주로 토양환경에서 transformation에 의한 유전물질의 전달과정에 대한 최근 연구동향을 간단히 기술하고자 한다.

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Cloning and Expression of Escherichia coli K13 Phytase Gene (appA13) Isolated from Seawater

  • Kim Young-Ok;Kim Han-Woo;Lee Jung-Ho;Kim Kyung-Kil;Lee Jong-Yun
    • Fisheries and Aquatic Sciences
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    • v.6 no.1
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    • pp.20-26
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    • 2003
  • A bacterial strain was isolated from seawater to screen for phytase activities. A colony had the highest activity and was identified as an Escherichia coli strain. Using primers derived from E. coli acid phosphatase appA sequence, we cloned a 1,495 bp DNA fragment connected with the pGEM-T vector. It was over-expressed under lac promoter combined with its native promoter in E. coli $DH5\alpha$. The expression of the phytase gene occurred during late exponential growth and the intracellular phytase production was 16.9 units/ml. The yield of recombinant phytate was 412-fold higher than that of wild type E. coli K13.

CLONING AND LIGHT-DEPENDENT EXPRESSION OF A cDNA FOR PEA CYTOSOLIC FRUCTOSE-1,6-BISPHOSPHATASE

  • Son, Tae-Jong;Hahn, Tae-Ryong
    • Journal of Photoscience
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    • v.4 no.3
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    • pp.141-145
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    • 1997
  • Polymerase chain reaction(PCR) was conducted with a pea cDNA library using two primers synthesized from homology analysis of amino acid sequences for animal and plant cytosolic FBPases. A PCR product with 650 bp long was cloned into pGEM-T vector and sequenced. The deduced amino acid sequence of the cDNA fragment was 98, 91, and 85% homologous with those of cytosolic FBPases from spinach, sugarbeet, and sugarcane, respectively. It was 51% homologous with amino acid sequence of FBPase from pea chloroplasts. Northern blot analysis was proceeded with the cDNA clone resulting that 1.2 kb transcript was highly expressed in light-grown pea leaves but almost not expressed in dark-grown etiolated pea seedlings. When peas grown in the light for 10 days were transferred to darkness, the transcript was gradually decreased with dark treatment, indicating that the expression of the enzyme was induced by continuous white light but suppressed by dark treatment. Pea cytosolic FBPase was highly expressed in leaves with trace amounts in stems. but almost not expressed in roots.

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QM/MM-MD Simulation을 통한 수용액 상에서의 Formamide Hydrolysis Mechanism 연구

  • Baek, Yong-Su;Choe, Cheol-Ho
    • Proceeding of EDISON Challenge
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    • 2014.03a
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    • pp.141-155
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    • 2014
  • Peptide bond hydrolysis는 세포 내외의 생화학반응에 있어서 핵심이다. 하지만 amide Hydrolysis Mechanism은 아직 명확하게 규명되지 않았다. pH가 중성인 물에서의 비 촉매 가수분해가 발생하는 몇몇 실험적 증거가 있지만, 해당 반응 매커니즘은 4 가지(non-assisted concerted, non-assisted step-wise, assisted concerted, assisted step-wise)로 여전히 논란이 있다. 이번 연구에서는, Formamide의 가능한 Hydrolysis Mechanism을 자세히 연구해보고자 한다. 먼저, Ab-initio 계산을 통해 4가지 반응 메커니즘의 다시 한번 확인하고, quantum chemical calculations과 quantum mechanical molecular dynamic이 결합된 (QMMD) simulation을 통하여 water solvent에서의 반응 메커니즘의 에너지관계를 규명하였다. 결론적으로 아직 계산이 끝나지 않은 supported concerted mechanism을 제외한 모든 계산에서 non-supported, supported 두 system 모두에서 step-wise가 일어나기 쉬웠고, non-supported 보다 supported mechanism이 선호됨을 보였다. Intermediate인 amino-gem-diol의 수용액 상에서 안정화 또한 나타났다. 이는 Ab-initio 계산만 통해서는 정확하게 산출할 수 없는 엔트로피의 영향을 잘 보여준다.

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Color Enhancement by Oxygen Torch in Blue Sapphires (블루사파이어와 루비의 고온산소 화염처리에 의한 색향상)

  • Song Oh Sung;Kim Sang Yeob
    • Journal of Surface Science and Engineering
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    • v.38 no.2
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    • pp.83-87
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    • 2005
  • We enhanced the color of blue sapphires and rubies successfully by using a oxygen-propane torch flame annealing, which had not been employed so far. We confirmed that about 1 mm-thick de-coloring of the corundum samples were available with 60 minutes flame annealing through eye evaluation, color coordination characterization, and methylene iodide immersion observation. We also suggest that the color centers such as $[Fe_{Al}^{\cdot}]$ may transform into transparent $[Fe_{Al}^{x}],\;[Cr_{A1}^{x}]$ sites with $[V_o^']$ generation at the elevated temperature in oxygen-rich atmosphere by diffusion mechanism. Our results implied that the longer diffusion time and the higher oxygen partial pressure might lead to the better de-coloring enhancement in corundum gem stones.

Characterization of High Pressure-High Temperature Treated Gem Diamonds (고압고온 처리된 보석용 다이아몬드의 감별 연구)

  • Song, Oh-Sung
    • Journal of Surface Science and Engineering
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    • v.39 no.5
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    • pp.229-234
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    • 2006
  • Diamonds have been widely employed as polishing media for precise machining and noble substrates for microelectronics. The recent development of the split sphere press has led to the enhancement of low quality natural diamonds. Synthesized and treated diamonds are sometimes traded deceptively as high quality natural diamonds because it is hard to distinguish among these diamonds with conventional gemological characterization method. Therefore, we need to develop a new identification method that is non-destructive, fast, and inexpensive. We proposed using new methods of UV fluorescence and X-ray Lang topography for checking the local HPHT stress field to distinguish these diamonds from natural ones. We observe unique differences in the local stress field images in treated diamonds using UV fluorescence and Lang topography characterization. Our result implies that our proposed methods may be appropriate for identification of the treated diamonds.

Performance Optimization of Parallel Algorithms

  • Hudik, Martin;Hodon, Michal
    • Journal of Communications and Networks
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    • v.16 no.4
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    • pp.436-446
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    • 2014
  • The high intensity of research and modeling in fields of mathematics, physics, biology and chemistry requires new computing resources. For the big computational complexity of such tasks computing time is large and costly. The most efficient way to increase efficiency is to adopt parallel principles. Purpose of this paper is to present the issue of parallel computing with emphasis on the analysis of parallel systems, the impact of communication delays on their efficiency and on overall execution time. Paper focuses is on finite algorithms for solving systems of linear equations, namely the matrix manipulation (Gauss elimination method, GEM). Algorithms are designed for architectures with shared memory (open multiprocessing, openMP), distributed-memory (message passing interface, MPI) and for their combination (MPI + openMP). The properties of the algorithms were analytically determined and they were experimentally verified. The conclusions are drawn for theory and practice.

Studies on Plant Parasitic Nematodes in the Fields of Codonopsis lanceolata (더덕(Codonopsis lanceolata) 재배지 기생선충의 발생상황)

  • 정도철;한상찬
    • Korean Journal of Plant Resources
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    • v.16 no.3
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    • pp.200-206
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    • 2003
  • This study were conducted to assess plant­parasitic nematodes infesting Codonopsis lanceolata. Ten kinds of plant­parasitic nematode gem including Meloidogyne and Pratylenchus were identified in 34 localities of C. lanceolata fields in three provinces in Korea. Meloidogyne, a dominant genus, was found in 97% localities and showed high average density as 1,700 nematodes per 300$m\ell$ soil. Its average density was 10 times higher in upland field than in paddy field.

Ableitungszirkumfix ge-+-e (파생접환사 ge-+-e)

  • Cho Kyun
    • Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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    • v.3
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    • pp.211-231
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    • 2001
  • Es gibt verschiedene Auffassungen $\"{u}ber$ die Formulierung der Ableitung, wobei nur die Suffixbildung als Ableitung einerseits gelten soll oder andererseits die Suffix- und $Pr\"{a}fixbildung$ zusammen als Ableitung gelten sollen. Hier wird die zweite Auffassung als Ableitung angesehen und danach $geh\"{o}rt$ auch die Zirkumfixbildung zur Ableitung. Das einzige Zirkumfix, mit dem die Substantive abgeleitet werden, ist ge-+-e und dessen Suffix kann gegebenenfalls nicht explizit $ausgedr\"{u}ckt$ werden. Diese Substantivableitung wird zuerst nach der Wortart der Basis und dann nach der Funktion oder Bedeutung $folgenderma{\ss}en$ klassifiziert: 1. Deverbale Substantive: 1) Abstrakta: Gefecht, $Ger\"{a}usch,\;Gest\"{o}ber$ - Wiederholung bzw. Dauer: $Gedr\"{o}hn$, Gekreisch, $Get\"{o}se$ - Pejorative Bewertung: Gejammer, Gerede, Geschreibe 2) Resultat bzw.Produkt: $Gem\"{a}lde$, Gewebe, Gewucher 3) Person bzw. Sache: $Gedr\"{a}nge,\;Gew\"{a}chs,\;Ger\"{o}ll$ 4) Instrumentalia: $Gebl\"{a}se,\;Gefa{\ss}$, Gestell b) Denominale Substantive: Kollektiva: Gehim, $Gel\"{a}nde$, Gerippe

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