• 제목/요약/키워드: Change of length

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동섬유를 이용한 바닥마감용 시멘트 모르터의 강도 및 열전도 특성 (Properties of the Strength and Thermal Conductivity of Floor Cement Morte Using Copper Fiber)

  • 박은배;윤길봉;정성철;홍상희;한천구
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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    • pp.173-176
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    • 2000
  • The objective of this paper is to investigate the properties of strength and thermal conductivity of floor cement mortal using copper fiber. Compressive strength thermal conductivity and length change are tested. According to the experimental results, compressive strength, thermal strength and thermal conductivity of mortar using copper finer are shown to be increased with increase of the contents of copper fiber and the aspect ratio. In case of length change of cement mortar using copper fiber also shows deline tendency compared with that of plain mortar.

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코어 변화에 대한 자계 특성 (Magnetic Field Properties About Core Change)

  • 김기준
    • 한국전기전자재료학회논문지
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    • 제25권2호
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    • pp.159-164
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    • 2012
  • In this paper, it tried to develop the core sensor for detection of micro magnetic field in electric wires. The sensor is non contact type and is consisted of ferrite core for low price. To investigate their properties for variations of current, it changed the number of winding and the length of sample core, it examined, to check the live wire situation in built-in wires, electrical characteristics due to difference between electric wires and core sensor. As the results, it verified live wire situation at the number of winding(5,000) and within length of 6[cm]. Also, it obtained magnetic field magnitude decreased inverse proportion ratio to a square about difference between electric wires and core sensor.

하이브리드 자동차 구동용 65kW급 SR Motor의 설계 (Design of 65kw Class Switched Reluctance Motor for HEV Drive)

  • 문재원;안진우
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제54권8호
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    • pp.358-363
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    • 2005
  • This paper presents the reasonable design parameters of a switched reluctance motor to drive a hybrid electric vehicle by using the equivalent magnetic circuit method. The designed motor can be redesigned by using finite element analysis as a variation of the parameter for the purpose of improving performance. This paper shows that a flat-topped current of a phase can be made from a change of the lamination stack length for high average torque and a lower torque ripple. The change of current falling time as a variation of turn-off angle was shown by finite element analysis. The core loss and copper loss were described. The torque of the redesigned motor is suitable for low and high speed ranges to drive a HEV. which is verified by the speed-torque curve.

개방형 구조의 진동형 히트파이프의 응축부 길이에 따른 추력 및 유동 가시화 (Thrust and Flow Visualization according to Length of Condenser Section of Open Pulsating Heat Pipe)

  • 손민재;최종욱
    • 한국가시화정보학회지
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    • 제21권3호
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    • pp.57-64
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    • 2023
  • An open pulsating heat pipe operates continuously by inflow and outflow fluids through an open-type condenser. The open pulsating heat pipe is a device capable of obtaining the thrust due to the variation of internal pressure during phase change. Therefore, the open pulsating heat pipe is a suitable device to move fluids if the heat source such as waste heat exists. Many numerical studies have not been sufficiently conducted on the open pulsating heat pipe. In this study, the numerical analysis of the open pulsating heat pipe is performed according to the length of the condenser section. The OpenFOAM software is used to obtain the thrust and the flow visualization for the open pulsating heat pipe.

스크린 망사의 견장과 오프닝의 변화 (The Opening Size Change for Screen Tension)

  • 정기영;강영립
    • 한국인쇄학회지
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    • 제28권1호
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    • pp.43-50
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    • 2010
  • The 200mesh screen was tensioned and fixed on a frame. When applied tension to 5N and 10N per unit area, a side length of opening of the screen was 163.223${\mu}m$ and 168.224${\mu}m$, respective. But side length not tensioned was 158.879${\mu}m$. We knew that a side length of opening of the screen rarely changes with tension applied to the screen. The appearances that a side length of opening of the screen expand little are due to a decreasing diameter of thread by means of tension. In a thickness measurement of screen, While the high density mesh screen that had a lot of knots that crossed a line of latitude and longitude per unit area appeared a higher numerical value, the low density mesh screen that had a few knots appeared a low numerical value.

다공확장벽을 이용한 플룸간섭의 제어 (Control of Plume Interference Using a Porous Extension)

  • Young-Ki Lee;Heuy-Dong Kim
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2003년도 제21회 추계학술대회 논문집
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    • pp.95-98
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    • 2003
  • The physics of the plume-induced shock and separation particulary at a high plume to exit pressure ratio and supersonic speeds up to Mach 3.0 with aid without a passive control method, porous extension, were studied using computational techniques. Mass-averaged Navier-Stokes equations with the RNG k-$\varepsilon$ turbulence model were solved using a fully implicit finite volume scheme and a 4-stage Runge-Kutta method. The courol methodology for plume-afterbody interactions is to use a perforated wall attached at either the nozzle exit or the edge of the missile base. The Effect of porous wall length on plume interference is also investigated. The computational results show the main effect of the porous extension on plume-afterbody interactions is to in the plume from strongly underexpanding during a change in flight conditions. With control, a change in porous extension length has no significant effect on plume interference.

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달팽이관내 기저막의 유한요소 모델링 (Finite Element Modeling of The Basilar Membrane in Cochlea)

  • 강희용;김봉철;양성모;임재중
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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    • pp.22-27
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    • 2001
  • Cochlea is well known to have the ability to analyze a wide frequency and this ability seems to be caused to the Basilar Membrane(BM) configuration. However, the relationship between the Cochlea frequency-position map is not clear. In this paper, the three-dimensional BM Model was made using the Finite Element method. Then, an attempt was made to examine the influence of the BM configuration on the Cochlea frequency-position map. Theoretical consideration reveals that the wide frequency-position of Cochlea is achieved by not only the BM configuration change along the length of the Cochlea but also the change of the Young's module of the BM along the length of the Cochlea.

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달팽이관내 기저막의 유한요소 모델링 (Finite Element Modeling of the Basilar Membrane in Cochlea)

  • 강희용;양성모;김봉철;임재중;용부중
    • 한국공작기계학회논문집
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    • 제11권1호
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    • pp.114-119
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    • 2002
  • Cochlea is well known to have the ability to analyze a wide frequency and this ability seems to be caused to the Basilar Membrane(BM) configuration. However, the relationship between the Cochlea frequency-position map is not clear. In this paper, the three-dimensional BM Model was made using the Finite Element Method. Then an attempt was made to examine the influence of the BM configuration on the Cochlea frequency-position map. Theoretical consideration reveals that the wide frequency-position of Cochlea is achieved by not only the BM configuration change along the length of the Coohlea but also the change of the Young's module of the BM along the length of the Cochlea.

염화마그네슘 첨가율에 따른 산화마그네슘 경화체의 길이변화 특성 (Shrinkage Strain Property of the Magnesium Oxide Matrix According to Magnesium Chloride Addition Ratio)

  • 정병열;이상수;송하영
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2013년도 추계 학술논문 발표대회
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    • pp.150-151
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    • 2013
  • Recently, the internal space organization of the building changes to the frame construction and flat slab construction in the wall type structure. And the use of light weight panel changing the internal joint use easily is increased. Therefore, in this research, the length change characteristic that the magnesium chloride addition rate reaches to the magnesium curing body tries to be studied. It could confirm according to the length change specific result that the magnesium chloride amount of addition reaches to the magnesium oxide curing body to expand. And the thing described below was the large-scale expansion the magnesium oxide addition rate 60%. And it showed up as 50, 40, 30, 20, and order of 10s (%). It could look at to form the hydrate of the SEM picture result needle-shaped of the Hardened.

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알루미나 시멘트와 무수석고를 이용한 그라우트의 재료적 특성 (Material Properties of Grout Using Alumina Cement and Anhydrite)

  • 홍기남;정진영;한상훈
    • 한국안전학회지
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    • 제26권5호
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    • pp.59-64
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    • 2011
  • This paper presents the research results performed to develope the shrinkage-free grout with high early strength. Alumina cement and anhydrite were utilized as the expensive tool to gain the shrinkage-free grout. The compressive strength, length change, and ettringite formation of the grout were investigated with compressive test, length change test, and X-ray diffraction. The more anhydrite was added into the grout, the larger the early expansion of the grout. In addition, the more anhydrite formated the more ettringite. From this study, It was conformed that the grout mixture with shrinkage-free property and high early strength is the mixture with the ratio of alumina cement and anhydrite of 40:60 by weight.