Reliability Analysis of cooler in Thermal Observation Device

열상감시장비의 냉각기 신뢰도 분석

  • Hong, Seok-Jin (DTAQ (Defense agency for Technology and Quality)) ;
  • Jung, Yun-Sik (DTAQ (Defense agency for Technology and Quality)) ;
  • Kim, Jin-Hwan (DTAQ (Defense agency for Technology and Quality))
  • 홍석진 (국방기술품질원 대구센터) ;
  • 정윤식 (국방기술품질원 대구센터) ;
  • 김진환 (국방기술품질원 대구센터)
  • Received : 2016.09.29
  • Accepted : 2016.11.10
  • Published : 2016.11.30


The cooler, which is the main part in a Thermal Observation Device (TOD), makes the TOD function by reducing the temperature. As the cooler is imported, overseas enterprises presented 20,000 hours as the operation time and the military have used the cooler as presented. However, failures have occurred occasionally after mass production stage. Therefore, we need to analyze the MTBF of the TOD cooler. So, military and defense industry companies collected the failure data of the TOD cooler. We analyze the MTBF of the TOD cooler using survival probability function and failure data. We find the optimal distribution by applying parametric method and estimate parameters. We determine that the Log-logistic distribution is the most appropriate for this data. Also, we analyze the reliability per hour of the TOD cooler. The result of MTBF of the TOD cooler was higher than that of presented by oversee enterprises.


Cooler;Reliability;TOD(Thermal Observation Device);Survival Analysis;Hazard Funtion;MTBF


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