Title :
Safety assessment for safety-critical systems including physical faults and design faults
Author :
Yu, Yangyang ; Johnson, Barry W.
Author_Institution :
Dept. of Electr. & Comput. Eng., Virginia Univ., Charlottesville, VA
Abstract :
Two types of faults, design faults and physical faults, are discussed in this paper. Since they are two mutually exclusive and complete fault types on the fault space, the safety assessment of safety-critical computer systems in this paper considers the hazard contribution from both types. A three-state Markov model is introduced to model safety-critical systems. Steady state safety and mean time to unsafe failure (MTTUF) are the two most important metrics for safety assessment. Two homogenous Markov models are derived from the three-state Markov model to estimate the steady state safety and the MTTUF. The estimation results are generalized given the fault space is divided by M mutually exclusive and complete types of faults
Keywords :
Markov processes; fault tolerant computing; safety-critical software; system recovery; systems analysis; design faults; hazard contribution; physical faults; safety assessment; safety-critical computer system modeling; steady state safety estimation; three-state Markov model; unsafe failure mean time; Circuit faults; Design engineering; Failure analysis; Hazards; Humans; Knowledge engineering; Life testing; Personnel; Safety; Steady-state;
Conference_Titel :
Reliability and Maintainability Symposium, 2006. RAMS '06. Annual
Conference_Location :
Newport Beach, CA
Print_ISBN :
1-4244-0007-4
Electronic_ISBN :
0149-144X
DOI :
10.1109/RAMS.2006.1677437