• 제목/요약/키워드: burst propensity

검색결과 2건 처리시간 0.017초

Effects of water saturation time on energy dissipation and burst propensity of coal specimens

  • Yang, Xiaohan;Ren, Ting;Tan, Lihai;Remennikov, Alex
    • Geomechanics and Engineering
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    • 제24권3호
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    • pp.205-213
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    • 2021
  • Water infusion has long been taken as an effective way to eliminate coal burst risk as coal properties can be loosen and soften by water infusion. However, not all industrial trials of water infusion for coal burst prevention have been necessarily effective in all situations as the effectiveness of this method can be affected by water infusion time, coal properties and the parameters of water injection. Hence, some fundamental issues including the effects of water infusion time on burst propensity and energy evolution need to be further discussed. In this paper, four groups of coal specimens with 0 day, 5 days, 10 days, and 15 days water saturation time are tested under uniaxial compression load with the application of AE monitoring. To comprehensively compare the burst behavior of coal specimens under different water saturation time, stress-strain curves, AE counts, fragmentation characteristics and burst propensity of these groups are analyzed. It was found by this research that sufficient water saturation can mitigate the burst behavior of coal samples while insufficient water infusion might cannot reach the burst mitigation aims.

경제충격 시기의 한계소비성향 분석 - FIML 마코프-스위칭 모형 이용 (Marginal Propensity to Consume with Economic Shocks - FIML Markov-Switching Model Analysis)

  • 윤재호;이주형
    • 한국산학기술학회논문지
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    • 제15권11호
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    • pp.6565-6575
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    • 2014
  • 본 논문에서 Hamilton의 마코프-스위칭 모형을 연립방정식으로 확장한 FIML 마코프-스위칭 모형을 제시해 보았다. 본 논문의 FIML 마코프-스위칭 모형을 LIML 마코프-스위칭 모형 등과 비교하면 LIML 마코프-스위칭 모형은 FIML 마코프-스위칭 모형의 특별한 경우이며 FIML 마코프-스위칭 모형은 연립방정식으로 확장된 일반화된 모형 형태를 띄게 된다. 본 논문의 FIML 마코프-스위칭 모형을 Campbell and Mankiw 소비함수에 적용해 본 결과, 2008년 부동산 거품 붕괴와 같은 경제충격 시기의 한계소비성향은 매우 민감도가 높아진다는 것을 알 수 있다.