• Title/Summary/Keyword: V-t 특성

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Identification and Characterization of Tobamoviruses Isolated from Commercial Pepper Seeds (시판 고추 종자에서 분리한 Tobamovirus의 동정 및 특성 조사)

  • 한정헌;손성한;나용준
    • Research in Plant Disease
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    • v.7 no.3
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    • pp.164-169
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    • 2001
  • Two Tobamoviruses showing different local lesion types on Nicotiana glutinosa was isolated from commercial pepper seeds. These viruses were designated Tobamovirus-6 (T-6) and Tobamovirus-19 (T-19). The biological and serological assays revealed that T-6 and T-19 were closely related to Pepper mild mottle virus (PMMoV) and Tomato mosaic virus (ToMV), respectively, The isolates also had low similarity in the array of viral coat protein gene sequences, of which T-19 was most identical to known strains of ToMV, while T-6 was closely related to PMMoV.

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Electrical Properties about Thermal and Water Degradation of Epoxy Powder for Bus Duct (부스닥트용 에폭시 분체도료의 열 및 수중열화에 대한 전기적 특성)

  • Kim, Hyun-Hee;Kim, Sang-Hyun
    • Fire Science and Engineering
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    • v.23 no.3
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    • pp.17-22
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    • 2009
  • Epoxy powder is being in use for insulation materials widely. Especially, in cause of coating insulation can be caused electrical fire and explosion by Joul's heat. This study has been compared and examined around breakdown, arc discharge, and V-t about insulation of Epoxy powder. Also, it has been researched about insulation which is cause of electrical fire and its basic data. According to temperature change, sample KS was stable before the Tg to be about $8{\sim}10%$ decrease in the breakdown test. In case of V-t and arc discharge, it had been kept up suitable characteristic. Also, in case of electrical characteristic, sample KS has excellent capacity.

A Study on the A.C.Breakdown Voltage-Temperature Characteristics for Air Insulated Power Installation (공기절연 전력설비를 위한 교류전로파괴전압-온도특성에 관한 연구)

  • 김상구;송현직;김영훈;이광식;이동인
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.9 no.1
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    • pp.47-53
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    • 1995
  • In this paper, the characteristics of breakdown voltage($\textrm{V}_{Brms}$) -temperature(T) for air insulated power installation in flowing air with variation of T(30[$^{\circ}C$] -180[$^{\circ}C$]) are presented. To study these subjects, needle-to-needle gap in the circular pipe(inner diameter 5[cm]) are used. Also, theories of gas discharge and hydrodynamics in pipe were used to analysis for the characteristics. The $\textrm{V}_{Brms}$ is proportional to flow velocity. At high velocity, $\textrm{V}_{Brms}$ is described the saturation. At high T(180[$^{\circ}C$]), $\textrm{V}_{Brms}$ is about 4.7(kV] lower than low T(30[$^{\circ}C$]). The empirical equation obtained from this study is $\textrm{V}_{Brms}=A\times{Log[Re}+B$. Where A, B : Constant.

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A Study on the Strength Characteristics of the FRP Bonding Method (FRP 이음방식에 따른 구조강도 특성에 관한 연구)

  • Kim, Kung-Woo;Kang, Dae-Kon;Baek, Myoung-Kee;Park, Jai-Hak
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.6
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    • pp.778-783
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    • 2015
  • We studied about the strength characteristics of the FRP bonding method due to reduce accident on the oceans and protect life for my people. We test tension and bending strength of butt joint, lap joint, V-scarf joint, X-scarf joint. The result of test, it's pattern is similar both tension and bending strength. Tension strength and bending strength was excellent in order to X-scarf-butt joint-V-scarf-lap joint. The tension strength is the best properties X-scarf showed a 57% strength rate of the basic material, and bending strength showed a 77% strength rate of the basic material. Overall, the X-scarf 12t joint has most excellent properties of tension and bending strength. The lap joint has worst properties of tension and bending strength. We have to test having different over-lay of V-scarf and X-scarf joint each 12t, 16t, 20t. V-scarf of 20t over-lay has excellent character of tension and bending strength. But X-scarf of 12t over-lay has excellent character of tension and bending strength. The results are shown to the contrary. The ship is received a lot of stress. it's hard to compare a direction both actual and test. But we can acknowledge material basic characteristic of strength through tension and bending test. We give the four repair method; butt joint, lap joint, V-scarf joint, X-scarf joint and the reduced ratio in comparison with basic material; In addition give the separated data for V-scarf and X-scarf characteristic of 12t, 16t, 20t overlay length. For our study repair man can select good repair method in his work station.

A Study on the Fabrication of CsI(T1) Radiation Sensor and its Spectroscopic Characteristics (CsI(T1) 방사선센서의 제작 및 분광특성 연구)

  • 권수일;신동호
    • Progress in Medical Physics
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    • v.13 no.1
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    • pp.44-50
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    • 2002
  • CsI(T1) single crystal was grown in a Bridgman growing apparatus, which has the diameter of 11 mm and the mole ratio of 0.001 mol%. Radiation sensors were made with CsITl)crystal and two photodiodes, and measured spectroscopic characteristics and linearity for gamma-ray and X-ray. The energy resolution of CsI(T1) radiation sensor has been measured with $^{22}$ Na, $^{137}$ Cs and $^{60}$ Co gamma standard sources. Also output linearity of CsITl) sensor was measured for diagnostic radiation region. The energy resolutions of CsI(T1) radiation sensor for 0.511MeV gamma-ray from Na-22 source, 0.662MeV from Cs-137 source, and 1.17MeV and 1.332MeV from Co-60 source were 13.2%, 8.3%, 6.7%, and 5.1% respectively. Also the output linearity up to 80mAs current for 60kVp, 80kvp, 100kVp, 120kVp tube voltages has been studied.

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Natural Convection Heat Transfer in Rectangular Air Enclosures With Adiabatic and Isothermal Horizontal Boundary Conditions (단열 및 등온수평 경계조건을 갖는 직각 밀폐용기내 공기의 자연대류 열전달)

  • 이진호;김무현;모정하
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.1
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    • pp.207-213
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    • 1990
  • Natural convection heat transfer in rectangular air enclosure was studied interferometrically and numerically for the use of adiabatic and constant temperature horizontal boundary conditions. In the isothermal horizontal boundary case with the temperature difference ratio, .DELTA. $T_{v/}$.DELTA. $T_{H}$ .simeq. 1 temperature distribution in the enclosure is strongly stratified and the average Nusselt Number is higher than that of adiabatic horizontal boundary case.ase.

Phenotypic and genetic characteristics of Vibrio ichthyoenteri isolated from the olive flounder, Paralichthys olivaceus of culturing size (미성어 양식 넙치, Paralichthys olivaceus에서 분리한 Vibrio icthyoenteri의 표현형 및 유전형적 특성)

  • Park, Su-Il;Lee, Hua;Kim, Su-Mi
    • Journal of fish pathology
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    • v.19 no.2
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    • pp.127-139
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    • 2006
  • From 2002 to 2004, various vibrios were isolated from the olive flounder, Paralichthys olivaceus of culturing size with disease signs. During this survey, it was known that the high proportion of Vibrio ichthyoenteri was occupied among the isolated vibrios. Generally, V. ichthyoenteri is well known as the pathogen of bacterial enteritis of olive flounder larvae. The aim of the present study was the compare the characteristics of two groups of V. ichthyoenteri, culturing sized olive flounder, and larvae of olive flounder showing the intestinal necrosis. The research was focused on the physiology, biochemistry, genetics in the two bacterial groups. The physiological and biochemical characteristics of the tested strains were very similar. The intergenic spacer (IGS) region between the 16S and 23S rRNA genes of 21 isolated strains and 3 reference strains, V. ichthyoenteri, were investigated by PCR fragment length typing and DNA sequencing. After the isolated strains were identified as V. ichthyoenteri, not only phenotypic characteristics of the isolated and reference strains but also homology of 16S-23S IGS of all isolated strains and reference strains as 99.1~100%. The V. ichthyoenteri showed 4 specific 16S-23S patterns and contained no-tRNA, tRNAGlu(TTC) , tRNAIle(GAT) tRNAAla(TGC) type .

Fabrication and characteristics of short channel nonvolatile SNOSFET memory devices (Short channel 비휘발성 SNOSFET 기억소자의 제작과 특성)

  • 강창수
    • Electrical & Electronic Materials
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    • v.4 no.3
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    • pp.259-266
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    • 1991
  • 1.5.mu.m의 찬넬길이를 갖는 short channel 비휘발성 SNOSFET 기억소자를 기존의 CMOS 1 Mbit 공정기술을 이용하여 제작하고 I$_{d}$-V$_{d}$ 및 I$_{d}$- V$_{g}$특성과 스윗칭 및 기억유지특성을 조사하였다. 그 결과 제작한 소자는 논리회로 설계에 적절한 전도특성을 가졌으며 스윗칭시간은 인가전압의 크기에 의존함을 보였다. 그리고 3V의 memory window 크기를 얻기 위해서 V$_{w}$ =+34V, t$_{w}$ =50.mu.sec 및 V$_{e}$=-34V, t$_{e}$=500.mu.sec의 펄스전압으로 각각 write-in과 erase할 수 있었다. 또한 기억상태는 10년이상 유지할 수 있음을 알 수 있었다.

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Dielectric Characteristics of Gaseous $SF_6$ for Impulse Voltages in Presence of a Metallic Particle in GIS (가스절연개폐장치에 있어서 금속입자 존재시 임펄스전압에 대한 $SF_6$가스의 절연특성)

  • 이복희;이경옥;이창준
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.1
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    • pp.22-29
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    • 2000
  • This paper deals with the dielectric characteristics of $SF_6$ gas gap stressed by $\pm$1.2/44[$mutextrm{s}$] non-oscillating impulse and $\pm$0.4[$mutextrm{s}$]/1.14[MHz] oscillating impulse voltages in the presence of a needle-shape metallic particle in gas-insulated switchgear(GIS). Breakdown voltage-time (V-t) and breakdown voltage-gas pressure (V-p) characteristics were investigated and discussed. The experiments were carried out under highly inhomogeneous field geometry with a needle protrusion whose length and radius are 10[mm] and 0.5[mm], respectively. The gas pressure ranges from 0.1 to 0.5[㎫]. As a result, it was found that the electrical breakdown for both the positive and negative polarity develops with steplike pulses in leader mechanism, When subjected to the positive oscillating impulse voltage, the minimum breakdown voltages appeared in all the gas pressure ranges and the V-t curves have a pronounced upturning at short times to breakdown and give a little dependence of the gas pressure. On the other hand, in the case of the negative polarity the dependence of the V-t and V-p characteristics on the wave shape of the applied voltages is known to be appreciable.

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