, Volume 7, Issue 2, pp 293–304 | Cite as

Reliability of ak-out-of-n system with repair and retrial of failed units

  • A. Krishnamoorthy
  • P. V. Ushakumari


We consider ak-out-of-n system with repair. Life times of components are independent exponentially distributed random variables with parameter λ i when the number of working units isi. Failed units are taken for repair to a station, manned by a single server, having no waiting room. The failed units are brought to an orbit, if the server is found to be busy, for retrial. Reliability of the system is computed in the following three situations: (i) Cold system (ii) Warm system and (iii) Hot system. Several other system characteristics are derived.

Key Words

Retrial Reliability Passage Times Phase Type Distribution 

AMS subject classification

60K25 90B22 


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Copyright information

© Sociedad de Estadística e Investigación Operativa 1999

Authors and Affiliations

  • A. Krishnamoorthy
    • 1
  • P. V. Ushakumari
    • 2
  1. 1.Department of MathematicsCochin University of Science and TechnologyKeralaIndia
  2. 2.Department of MathematicsIndian Institute of ScienceBangalore

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