• 제목/요약/키워드: Testing Temperature

검색결과 1,542건 처리시간 0.027초

AE 계측에 의한 고온용 흑연재료의 경함측정에 관한 연구 (Defect Measurement of Graphites for High Temperature Application by AE Technique)

  • 최만용
    • 한국정밀공학회지
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    • 제9권2호
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    • pp.122-127
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    • 1992
  • In this study, we investigated defects of graphite by three NDT methods which are ultrasonic testing at 5 MHz, micro-forused X-ray testing and AE testing. As the detection of AE signals generated from graphite tensile specimens, we calculated location of AE sources and compared them with UT and X-ray test results in detecting defects of several specimens, Acoustic emission testing could be applied to some graphites which have fine grains of a few tens of micrometer, but it was difficult to those in lager grain of few fo milimeter. Also, we could understand what kind of defects has affected on tensile fracture of graphite.

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Nicalon/CAS 세라믹 복합재료의 인장특성 (Tension Behavior of Nicalon/CAS Ceramic Composites)

  • 김정국;김원경
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.232-237
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    • 2004
  • The tension behavior of Nicalon/CAS glass-ceramic matrix composites was investigated. Infrared (IR) thermography was employed for two different types of $Nicalon^{TM}/CAS$ composites, i.e., cross-ply and unidirectional specimens. During tensile testing, an IR camera was used for in-situ monitoring of progressive damages of $Nicalon^{TM}/CAS$ samples. The IR camera provided the temperature changes during tensile testing. Microstructural characterization using scanning electron microscopy (SEM) was performed to investigate the fracture mechanisms of $Nicalon^{TM}/CAS$ composites. In this investigation, the thermographic NDE technique was used to facilitate a better understanding of the fracture mechanisms of the $Nicalon^{TM}/CAS$ composites during tensile testing.

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가속시험을 통한 Electroluminescent film의 활성화 에너지 추정 (Estimation of Activation Energy of Electroluminescent film by Accelerated Life Test)

  • 김수경;형재필;오길구;임홍우;김명수;오근태
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제15권1호
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    • pp.52-59
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    • 2015
  • In this Study, we tested electroluminescent film to accelerate life by temperature, humidity, voltage, and frequency. We analyzed brightness data to estimate activation energy and verify it's suitability. All of the tests performed in operating condition. Because electroluminescent film is mostly degraded by fluorescent in operating condition. Two different sample groups were tested and compared to find common parameter.

적외선을 이용한 비파괴검사 기술 (Nondestructive Testing Technique using Infrared Thermography)

  • 박문호;이익환
    • 비파괴검사학회지
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    • 제14권4호
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    • pp.244-249
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    • 1995
  • 적외선을 이용한 비파괴검사 방법은 검사자가 검사체의 온도를 분석하여 검사체의 건전성을 평가할 수 있도록 개발된 방법이다. 이것이 최근에는 화력발전소 및 원자력발전소 등과 같은 다양한 산업에 적용되어 사용되고 있다. 따라서, 본 보고서는 적외선을 이용한 비파괴검사의 기초적인 원리, 적외선 측정 장비의 기본 원리 및 그것의 응용분야를 기술하였다.

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가속 시험법에 의한 연료전지 전극 특성 (Electrode Performance by Accelation Testing in Phosphoric Acid Fuel Cell)

  • 김창수;송락현;신동열
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1409-1412
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    • 1994
  • The electrodes for Phosphoric Acid Fuel Ceil were fabricated as a condition of PTFE contents in electrocatalyst layer and sintering temperature in the range of 25 -- 65 wt% and 310 -- $390^{\circ}C$, respectively. For the fabricated electrode, the accelation testing of cathode half cell at open circuit potential was investigated. While the performance of electrode showed maximum at the low level of PTFE contents in the initial stage of accelation testing, the maximum performance was shifted to higher PTFE contents of 45wt% after 24hrs accelation testing.

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Design and Characteristics Analysis of the 78 kWe Grade Synchronous Generator for Disused Diesel Engines

  • Youn, Jun-Seop;Kim, Hae-Joong;Kim, Youn-Hwan;Moon, Jae-Won
    • Journal of Magnetics
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    • 제22권1호
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    • pp.122-132
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    • 2017
  • This study dealt with the design process of the 78 kW permanent magnet synchronous generator for engines. After the calculation of the basic dimensions through a theoretical method in the process of initial model design, FEA (finite-element analysis) and a d,q-axis equivalent circuit were used to identify the generator characteristics depending on the number of poles. With the use of the space harmonic analysis method, the back-EMF (electromotive force) and THD were checked, and then the number of slots was determined. In addition, the most optimized generator dimensions were determined through a sizing optimization technique. Based on this, the optimum model with enhanced efficiency, material costs, and temperature characteristics was derived, and the availability of the design method was confirmed through a comparative analysis of the initial and optimum models.

Non-destructive Leakage Location Analysis Method in Substrate Behavior Response Testing of Waterproofing Membrane Systems using Thermal Emission Camera

  • 오규환;강파;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 추계 학술논문 발표대회
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    • pp.47-48
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    • 2017
  • The substrate behavior response testing outlined in KS F 2622 evaluates the leakage cause of waterproofing membrane systems when subjected to the concrete joint load behaviors by removing the waterproofing layer after testing, relying mostly on visual observation and subjective analysis. A non-destructive leakage cause and failure type analysis method is proposed currently in this study by the means of detecting leakage paths using thermal emission imaging systems. Test specimens are placed in varying temperature conditions after the concrete joint movement testing and are scanned using the thermal emission camera to determine the location and dimension of the adhesion failure/leakage path beneath the waterproofing membranes.

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시료크기 및 인장속도에 따른 지오그리드의 광폭인장강도 평가 (Wide-Width Tensile Strength Properties of Geogrids according to Specimen Length and Testing Speed)

  • 조삼덕;이광우;오세용
    • 한국지반신소재학회논문집
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    • 제6권2호
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    • pp.21-26
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    • 2007
  • 지오그리드의 인장강도 특성은 시험온도, 시료길이, 변위측정방법, 인장속도 및 시험장치 등에 영향을 받는다. 지오그리드의 인장강도시험법은 ASTM 06637 및 ISO 10319에 규정되어 있다. 그러나 이 두 시험법은 인장속도 및 시료길이에서 다소간의 차이를 가진다. 본 연구에서는 국내에서 많이 사용되고 있는 세 가지 종류의 지오그리드를 대상으로 일련의 광폭인장강도시험을 수행하여 시료길이 및 인장속도가 지오그리드의 광폭인장강도에 미치는 영향을 평가하였다.

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표면방전 현상의 적외선 카메라 관측에 관한 연구 (A Study on the Observation of IRR Camera in Surface Discharge Image)

  • 임장섭;김진국;김현종;이우선;이진;김덕근;이학현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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    • pp.563-566
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    • 2003
  • The conventional testing as IEC-60587 is widely used in suface aging measurement of outside insulator those testing can carry out very short time in Lab testing. Also IEC-60587 testing is able to offer the standard judgement of relative degradation level of out side HV machine. Therefore it is very useful method compare to previous conventional tracking testing method and effective Lab testing method, But surface discharges(SD) have very complex characteristics of discharge pattern so it is required estimation research to development of precise analysis method. In recent, the study of IRR Camera is carrying out discover of temperature of power equipment through condition diagnosis and system development of degradation diagnosis.

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