• 제목/요약/키워드: V shape

검색결과 1,236건 처리시간 0.026초

침전극하에서 XLPE의 절연파괴강도의 통계적평가 (Statistical Analysis of Breakdown Voltage using needle electrode inserted in XLPE)

  • 오재형;전은아;박운호;박수길;박대희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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    • pp.872-874
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    • 1998
  • The needle electrode was inserted in virgin and 1.000 hr aged XLPE which is the insulation used for 22.9 kV underground distribution cable with the distance of 1, 1.5 and 2mm respectively. Breakdown voltage were measured for the virgin and 1.000 hr aged specimen and statistically evaluated through Weibull distribution. As the of electrode increase in virgin and 1.000 hr aged specimen. shape parameter and scale parameter showed increase coincidently. For shape parameter, the value of aged specimen showed the higher than that of virgin specimen.

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Ferromagnetic Resonance Observation of Martensitic Phase Transformation in Ni-Mn-Ga Ferromagnetic Shape Memory Films

  • Dubowik, J.;Kudryavtsev, Y.V.;Lee, Y.P
    • Journal of Magnetics
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    • 제9권2호
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    • pp.37-39
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    • 2004
  • Polycrystalline Ni-Mn-Ga films have been deposited onto mica substrates held at 720 K by flash-evaporation method. At room temperature the films have a tetragonal structure with a = b = 0.598 and c = 0.576 nm typical for bulk $Ni_2MnGa$ below a martensitic transformation. Temperature measurements of ferromagnetic resonance reveal a martensitic phase transformation at 310 K. The transformation brings about a substantial decrease in the effective magnetization and a drastic increase in the ferromagnetic resonance linewidth due to a strong increase in the magnetic anisotropy in the martensitic phase.

유한요소법을 이용한 전방압출공정의 내부결함에 관한 연구

  • 김태형;김병민;강범수;최재한
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1992년도 춘계학술대회 논문집
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    • pp.79-83
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    • 1992
  • According to the variation of hydrostatic pressure on the central axis of deformable material, the V-shaped central bursting defect may be created on extrusion or drawing processes. The process factors whichaffect the generation of defects are die semi-angle, reduction ratio of cross-sectional area, friction factor, material properties and so on. The combination of these factors can determine the prossibility of defect creation and the shape of various round holes which have been created inside already. By the rigid plastic finite element method, this paper describes the observations of change in shape of a round hole with process conditions suchas die semi-angle, reduction ratio of cross-sectional area and friction factorat the unsteady state of axi-symmetrical extrusion process when the round hole is alreadyexisted inside the original billet, and also, the effects of process factors are investigated to prevent the possible defects.

다중 간극형 오존발생장치의 특성 (The Characteristics of Multi Gap Type Ozonizer)

  • 김금영;문경수;전병준;박용권;김상구;김영훈;김영길;이광식
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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    • pp.145-148
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    • 1999
  • In this paper, multi gap type ozonizer(MGO) has been designed and manufactured. The ozonizer is equipped with three electrodes(central electrode of screw shape, internal electrode and external electrode) of cylinder shape. This paper describes the following two characteristics: $\circled1$ The characteristics of discharge with variation of output voltage of AC H.V source, flux of oxygen supplied gas and discharge voltage. $\circled2$ The characteristics of ozone generation by varying flux and discharge power.

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Structural analysis of horizontal axis wind turbine blade

  • Tenguria, Nitin;Mittal, N.D.;Ahmed, Siraj
    • Wind and Structures
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    • 제16권3호
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    • pp.241-248
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    • 2013
  • The wind turbine blade is a very important part of the rotor. Extraction of energy from wind depends on the design of blade. In this work, the analysis is done on a blade of length 38.95 m which is designed for V82-1.65 MW horizontal axis wind turbine (supplied by Vestas). The airfoil taken for the blade is NACA 634-221 which is same from root to tip. The analysis of designed blade is done in flap-wise loading. Two shapes of the spar are taken, one of them is of square shape and the other one is combination of square and cross shape. The blade and spar are of the same composite material. The Finite element analysis of designed blade is done in ANSYS. This work is focused on the two segments of blade, root segment and transition segment. Result obtained from ANSYS is compared with the experimental work.

Riblet 홈을 가진 원주의 저항감소에 관한 연구 (An Experimental Study on Drag Reduction of Grooved Cylinders)

  • 임희창;이상준
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집B
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    • pp.508-513
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    • 2000
  • An experimental investigation has been carried out for two circular cylinders having different groove configurations(U and V-shape). The results were compared with those for the smooth circular cylinder. The drag force, mean velocity and turbulent intensity profiles of wake behind the cylinders were measured with varying the Reynolds number $Re=8000{\sim}14,000$ based on the cylinder diameter. As a results, the U-groove circular cylinder was found to be most effective riblet shape with reducing the drag up to 21%. As the Reynolds number increases, the vortex shedding frequency of the grooved cylinders becomes a little larger, compared to the smooth cylinder. The flow visualization using the smoke-wire technique was also carried out to see the flow structure qualitatively.

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Opisthorchis felineus and Metorchis bilis Metacercariae in Cyprinid Fish Leuciscus idus in Nura-Sarysu River, Kazakhstan

  • Kiyan, Vladimir S.;Bulashev, Aitbay K.;Katokhin, Aleksey V.
    • Parasites, Hosts and Diseases
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    • 제56권3호
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    • pp.267-274
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    • 2018
  • Aim of the present study was to provide presence of opisthorchiid metacercariae in cyprinid fish Leuciscus idus in Nura-Sarysu river, Kazakhstan. Infection rate of the ides by the metacercariae was 42%. The metacercariae, similar morphologically to those of the liver flukes, were found: elliptical in shape, $0.19-0.25{\times}0.15-0.22mm$, oral and ventral suckers nearly equal size, and excretory bladder O-shape with black content, occupying posterior part of the body. The metacercariae were divided into 2 groups with differences in size and thickness of cyst wall. Adult flukes were recovered from the Syrian hamsters infected with the opisthorch metacercariae and identified with morphological characters to Opisthorchis felineus and Metorchis bilis. DNA sequences of ITS1, ITS2, and cox1 supported the taxonomic assignment.

Showering Discharge형 오존발생장치의 특성 (The Characteristics of Showering Discharge Type Ozonizer)

  • 김금영;문경수;송현직;이광식;이동인;전영주
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 E
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    • pp.2248-2250
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    • 1999
  • In this paper, showering discharge type ozonizer has been designed and manufactured. The ozonizer is equipped with three electrodes(central electrode of screw shape, internal electrode and external electrode) of cylinder shape. This paper describes the following two characteristics: (1) The characteristics of discharge with variation of output voltage of AC H.V source, flux of oxygen supplied gas and discharge voltage. (2) The characteristics of ozone generation by varying flux and discharge power.

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Conditions for Moire Free Contact-Type 3 Dimensional Displays

  • Song, Yoon-Chul;Saveljev, Vladimir V.;Son, Jung-Young;Yeom, Seok-Won;Vashpanov, Yu. A.
    • Journal of the Optical Society of Korea
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    • 제12권2호
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    • pp.93-97
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    • 2008
  • The superposing angle of the viewing zone forming optics and the display panel in the contact type 3 dimensional imaging systems for minimizing $moir{\acute{e}}s$ is found for a rectangular shape pixel with different aspect ratios. The angles are $26.2609^{\circ}$ for square shape pixels and $13.9858^{\circ}$ for the rectangular with aspect ratio 2. These angles result in the $moir{\acute{e}}s$ with the smallest period for the respective aspect ratio. The effectiveness of the angles is also experimentally demonstrated.

다목적 소형 부유시설의 몰수부 형상변화에 따른 파랑중 수직운동 특성에 관한 연구 (A Study on the Characteristics of Vertical Motions due to Changes of Submerged Shape in the Multi-Purpose Small Floating Body)

  • 오유나;김상원;이경우;한승재;김인철
    • 수산해양교육연구
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    • 제28권4호
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    • pp.1024-1030
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    • 2016
  • This study gives the vertical motion analysis due to changes in Submerged shape of Multi-Purpose Small Floating Body in irregular waves using the commercial code(MAXSURF v.20) based on the Panel method. To verify the commercial code prior to the analysis, we guarantees the reliability of this paper's results using the commercial code by comparing with the results of experimental results on Catamaran. The anlysis conditions are ITTC wave spectrum, each encounter angle. Finally, we analyze the result of ship's response spectra for vertical motions.