• 제목/요약/키워드: energy principle

검색결과 1,034건 처리시간 0.025초

용사 열차폐 코팅층의 두께가 열응력에 미치는 영향 (A Study on the Effects of the Thickness of Top Coat on the Thermal Stresses of a Sprayed Thermal Barrier Coating)

  • 김형남;양승한
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
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    • pp.223-225
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    • 2004
  • Based on the principle of complementary energy an analytical method is developed for determining thermal stress distribution in an thermal barrier coating. This method gives the stress distributions which satisfy the stress-free boundary conditions at the edge. Numerical examples are given in order to verify the method and to investigate the thickness effects of the ZrO$_2$-8wt%Y$_2$O$_3$ top coat on the integrity of thermal barrier coating consisted of IN738LC substrate and MCrAlY bond coat.

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미래형 주거개발에 관한 연구 - 미래주거 개발방향과 계획요소 - (A Study on the Development of the Future Housing - The Development Direction and the Planning Factors of the Future Housing -)

  • 권소현
    • 한국주거학회논문집
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    • 제7권2호
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    • pp.109-120
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    • 1996
  • This study which aimed to propose development directions for the future housing through the social change tries to predict the change of the future. Establish directions for planning of concept-Sustainability. Human-friendliness. High Technology and, with reference to case study and literature judge feasibility of them. The major findings were as follows : 1. Development direction related to the future housing can be classified into 7 principle : energy-saving, resource-saving, natural adaptation, community, user participant, super high level, and home intelligent. 2. Planning factors of the future housing can be divided into several itemes.

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열-전기-기계 하중 하에서의 고차 지그재그 판이론 (Higher Order Zig-zag Piezoelectric Plate Theory Under Thermo-electric-mechanical Loads)

  • 조맹효;오진호
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집A
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    • pp.426-431
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    • 2000
  • A decoupled thermo-piezoelectric-mechanical model of composite laminates with surface bonded piezoelectric actuators, subjected to externally applied load, temperature change load, electric field load is developed. The governing differential equations are obtained by applying the principle of free energy and variational techniques. A higher order zigzag theory displacement field is employed to accurately capture the transverse shear and normal effects in laminated composite plates of arbitrary thickness.

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개선된 영전류 PWM 부스트 컨버터 (Improved ZCS-PWM Boost Converter)

  • 안준연;최항석;유권종;조보형
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2002년도 전력전자학술대회 논문집
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    • pp.382-385
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    • 2002
  • In this paper, an improved ZCS-PWM boost converter is proposed to minimize conduction loss by flowing resonant current only through the auxiliary circuit. The operation principle of the proposed converter is explained and design procedure is established. Experimental results are presented to verify the theoretical analysis.

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공진 DC Link 순시 정현파 전류 추종형 인버터를 이용한 유도전동기 제어시스템 (Instantaneous sinusoidal currant tracking mode inverter with quasi-resonant Link in DC side)

  • 유권종
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1990년도 하계학술대회 논문집
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    • pp.324-327
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    • 1990
  • In this paper describes the feasibility study on a single-phase / three-phase voltage-fed inverter using 1GBTs, incorporating voltage-mode quasi-resonant DC Link and the instantaneous Sinusoidal Current tracking adaptive control implementation under zero voltage switching resfriction. The simulation and experimental results are shown here and discussed for single-phase voltage-fed and three-phase voltage-fed inverter in order to verify the new operating principle of the Inverter topology proposed here.

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Brief Introduction to Angle-Resolved Photoemission Spectroscopy

  • 김형도
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.82-82
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    • 2012
  • Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool to investigate the electronic structure of a single-crystalline solid. After the development of a two-dimensional electron detector, it became a basic experimental method in solid state physics comparable to other powerful tools such as x-ray and neutron scatterings. In this tutorial, I talk briefly on the basic principle of ARPES and its recent and future direction of development.

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OBTAINING BOUNDARY TANGENTIAL COMPONENTS OF POTENTIAL MAGNETIC FIELDS BY A VARIATIONAL METHOD

  • CHOE G. S.
    • 천문학회지
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    • 제31권2호
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    • pp.89-93
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    • 1998
  • An attempt is made to find the boundary tangential components of potential magnetic fields without constructing solutions in the entire domain. In our procedure, the magnetic energy is expressed as a functional of tangential and normal magnetic fields at the boundary and is minimized by the variational principle. This paper reports a preliminary study on two dimensional potential fields above a plane.

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정밀 열전형변환기를 사용한 기준직교류전력비교기 (Reference DC/AC Power comparator on the basis of precision thermal converters)

  • 박영태;장석명
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 B
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    • pp.676-678
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    • 1995
  • The Paper describes a dc/nc power comparator for measurement of power. Based on a thermal principle, the instrument performs ac-dc transfer and absolute power and energy measurements in the range of currents from 0 to 5 A, voltages from 60 to 240 V, power factors from 0 to 1 and frequencies from 50 to 1000 Hz. The ac-dc transfer accuracy is better than 20 ppm at unity power factor and better than 50 ppm at 0.5 power factor.

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열-전기-기계 하중에서의 복합재 평판의 응력해석 (Refined Decoupled Stress Analysis for Thermo-piezoelectric Composite Plate)

  • 오진호;조맹효
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2000년도 추계학술발표대회 논문집
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    • pp.46-49
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    • 2000
  • A decoupled thermo-~lezoelectric-mechanical model of composite laminates with surface bonded piezoelectric actuators, subjected to externally applied load, temperature change load, electric field load is developed. The governing differential equations are obtained by applying the principle of free energy and variational techniques. A higher order zigzag theory displacement field is employed to accurately capture the transverse shear and normal effects in laminated composite plates of arbitrary thickness.

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Embodiment of all-optical switching phenomena on a GaAs waveguide

  • 이상재
    • 센서학회지
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    • 제5권5호
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    • pp.85-95
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    • 1996
  • Based on the transmission of coupled gap solitons in nonlinear periodic media, we present an all-optical switching scheme which has a novel architecture and principle. The proposed switch with an extremely small switching element can be realized on a semiconductor waveguide. We here investigate the switching performance with a GaAs waveguide in order to give criteria for the experimental realization of the all-optical switching phenomena. We also suggest a variation of an index-matching scheme to solve the technical problem such as the input-energy coupling into a periodic waveguide.

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