34 lines
746 B
Mathematica
34 lines
746 B
Mathematica
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function [A,MTTF,MTBF] = evaluate_CR(nm,n,lambdaB,lambdaR,muB,muR)
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%% model definition
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% notice: here last state is, by definition, one of the system failed states
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[nstates,Qav,Qre,pi0,av_indx] = CTMC_CR(nm,n,lambdaB,lambdaR,muB,muR);
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%% solution of the availability model
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tildeQ = Qav;
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tildeQ(:,end) = ones(nstates,1);
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elast = zeros(1,nstates);
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elast(end) = 1;
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% steady-state probability vector
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pi = (tildeQ')\(elast');
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% availability = MTTF/MTBF
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A = sum(pi(av_indx));
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%% solution of the reliability model
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hatQ = Qre(av_indx,av_indx);
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hatpi0 = pi0(av_indx);
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tau = -(hatQ')\(hatpi0');
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MTTF = (tau')*ones(length(av_indx),1);
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%% evaluate MTBF
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MTBF = MTTF/A;
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fprintf("Percentage of up states is %f\n", 100.0*length(av_indx)/nstates);
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end
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