• Title/Summary/Keyword: 흑체

Search Result 46, Processing Time 0.039 seconds

Nano-particle size detection by LII decay method (LII 감쇄법을 이용한 나노입자 크기측정)

  • 엄규섭;박성종;박철웅;한재원;최원호;정광화;신용현
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2002.07a
    • /
    • pp.60-61
    • /
    • 2002
  • Laser-induced incandescence (LII) 측정법은 조사된 레이저에 의하여 입자가 가열됨에 따라서, 그 온도에 상응하는 흑체복사의 시간적 감소추이가 입자의 크기에 따라서 달리 나타나는 것을 이용하여 입자의 크기를 측정하는 방법이다. LII 감쇄법은 레이저에 의하여 가열된 입자의 에너지 균형 상관식에서 입자의 크기가 클수록 신호의 감쇄속도가 느리고, LII 신호의 감쇄비가 실험적으로 입자의 크기에 비례한다는 사실을 이용하여 연소진단에 응용되어 왔다. (중략)

  • PDF

대형 열진공챔버 내 심우주 모사용를 위한 L$N_2$ 순환장치

  • 문귀원;조혁진;이상훈;서희준;최석원
    • Bulletin of the Korean Space Science Society
    • /
    • 2004.04a
    • /
    • pp.77-77
    • /
    • 2004
  • 인공위성은 정상궤도에 들어선 후부터 수명을 다하는 시기까지 각종 복사, 열(온도차), 고진공, 미세중력, 미세운석과 우주파편 등에 의해 영향을 받게 된다. 특히, 위성체에 미치는 열환경은 위성이 궤도를 그리며 운동하는 동안 태양과 지구로부터의 복사량의 크기 및 분포에 따라 결정되는데, 약 5,50$0^{\circ}C$의 흑체온도를 갖고 있는 태양과 -27$0^{\circ}C$의 심우주는 위성체에서 태양이 비추는 부분과 반대편과의 온도를 극한으로 만들게 된다. (중략)

  • PDF

Measurement and Validation of Infrared Signature from Exhaust Plume of a Micro-Turbo Engine (마이크로 터보 엔진 배기 플룸에서의 적외선 신호 측정 및 검증)

  • Gu, Bonchan;Baek, Seung Wook;Jegal, Hyunwook;Choi, Seongman;Kim, Won Cheol
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.44 no.12
    • /
    • pp.1054-1061
    • /
    • 2016
  • Development of an accurate infrared signature (IR) measurement system is expected to contribute in the development of low observable technology and the spectroscopic analysis of electromagnetic radiation. Application of a spectroradiometer (SR) allows for the measurement of detailed infrared signature from the exhaust plume due to its own heat source. Establishment of a measurement system using a micro-turbo engine is intended to simulate the modelling of the aircraft plume. The engine was installed on a test stand to measure the engine performance. The IR signature was measured by placing the SR perpendicular to the axis line of the exhaust plume. Reference data from the blackbody were also measured to calibrate the raw data, and the infrared signature of the background was also measured for comparison with that of the plume. The calibrated spectral radiance was obtained through the data reduction process and the results were analyzed in specific bands. The experiments revealed that the measurement system established here showed sufficient performance for further comprehensive analysis.

Mechanical Stability Analysis of PCB and Component for Launch and On-orbit Environment based on Fatigue Failure Theory and FEM (피로파괴 이론과 FEM에 기초한 발사 및 궤도 환경에서의 기판 및 소자의 구조건전성 분석)

  • Jeong, Suk-Yong;Oh, Hyun-Ung;Lee, Kyung-Joo;Kim, Byoung-Soo
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.39 no.10
    • /
    • pp.952-958
    • /
    • 2011
  • On-board IR calibration device has been developed for calibration of spaceborne image sensor. It is composed of a blackbody to provide two different radiance temperatures, tilt mirror with a function of stow and deploy to view the blackbody during the calibration and on-board calibration control unit to control the function of the blackbody and tilt mirror. In this paper, to guarantee the structural safety of the unit, the structural and thermal analysis including a thermo-elastic analysis for verifying structural safety on the soldered part of chips have been performed. In addition, safety margin of the chips on the PCB obtained from the conventional analytical method has been compared to the results from the FEM analysis.

Responsivity and Noise Evaluation of Infrared Thermal Imaging Camera (적외선열화상카메라의 응답 및 노이즈 특성 평가)

  • Kim, Dong-Ik;Kim, Ghiseok;Kim, Geon-Hee;Chang, Ki Soo
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.33 no.4
    • /
    • pp.342-348
    • /
    • 2013
  • In this paper, the evaluation method for the responsivity and noise characteristics of an infrared thermal imaging camera was presented. Signal transfer function and noise equivalent temperature difference of the infrared thermal imaging camera were obtained by using a differential mode blackbody that is able to control the temperature difference ${\Delta}$T between an infrared target and its background. And we verified the suitability of our evaluation method through comparison between the found noise equivalent temperature difference and the specification of the camera. In addition, the difference of 0.01 K of the two noise equivalent temperature differences calculated from with and without nonuniformity correction suggests that the nonuniformity correction is essential process for the evaluation of the infrared thermal imaging camera.

Development of 100W LED flood lighting with tunable colors and color temperatures (광색가변 및 색온도 제어용 100W급 투광기 개발)

  • Song, Sang-Bin;Kim, Gi-Hoon;Kim, Jin-Hong;Cheon, Woo-Young
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2007.11a
    • /
    • pp.89-94
    • /
    • 2007
  • 이 논문에서는 100W급 Discrete LED 투광기 조명 제품 개발에 관한 것으로, 3W RGBA LED를 이용하여 광색 및 색온도 제어가 가능하도록 광학/방열/회로/시스템 설계를 통한 시제품을 제작하였다. 그 결과, 색온도 $2,000{\sim}10,000K$ 범위에서 흑체궤적에 정확히 일치하면서 연색지수가 $71{\sim}91$까지 고연색성을 실현하였으며, 동작전압 $90{\sim}250VAC$, 효율 87%, 역률 93이상의 양호한 전기적 특성을 나타냈다. 또한 투광기의 협각/중각/광각 배광을 만족하기 위하여 LED 렌즈를 설계하였으며, 신뢰성 확보 및 주위온도에 따른 광출력 변화를 최소화할 수 있는 방열설계를 실시하였다.

  • PDF