01256nas a2200301   4500000000100000000000100001000000100002008004100003260000900044653003700053653001200090653002900102653002800131653003300159653002300192653001600215653003400231653001400265653002600279653002300305100002600328700002300354700002800377245011800405300001200523490000700535520041200542       2012                            d  c201210abusiness-critical infrastructure10adefects10adependability indicators10aevolu¬tion of software10afault-tolerant architectures10aIT-infrastructures10amacrograph.10aMarkov and semi-Markov chains10aModelling10asafety block diagrams10avariable parameter1 aVyacheslav Kharchenko1 aOleg Odarushchenko1 aValentina Odarushchenko00aMulti-Fragmental Availability Models of Critical Infrastructures with Variable Parameters of System Dependability  a248-2650 v283 a This paper presents the development of the MFMC-based methodology and technique for modelling and quantitative availability assessment of critical IT-infrastructure consisting of maintained and partially unmanned systems. It takes into consideration a variation of system and component parameters and, in particular, variation of failure rates caused by detection and elimination of design faults.</html>