Table 5.

Obtained reliability functions for each subsystems

Subsystem	Baseline hazard rate parameters (PLP model*)		Reliability function
	b (Scale)	a (Shape)
Lo	9.592	1.950	$R_{Lo{.}_{\theta }}\left(t,\nu \right)={\left[1-0.97ln\left({\left(exp\left(-{\left(\frac{t}{9.592}\right)}^{1.95}\right)\right)}^{exp\left(-0.6{\nu }_1-1.05{\nu }_2+0.49{\nu }_4-0.17{\nu }_5-0.83{\nu }_{10}\right)}\right)\right]}^{\raisebox{1ex}{$-1$}\!\left/ \!\raisebox{-1ex}{$0.97$}\right.}$
DT.1 (1st layer)	7.123	1.293	$R_{\text{DT}.1}\left(t,{\nu }^{\prime }\right)={\left(\text{exp}\left(-{\left(\frac{t}{7.123}\right)}^{1.293}\right)\right)}^{exp\left(-2.02{\nu }_2^{{}^{\prime }}-1.04{\nu }_6^{{}^{\prime }}\right)}$
DT.1 (2nd layer)	7.319	1.611	$R_{\text{DT}.1}\left(t,{\nu }^{\prime }\right)={\left(\text{exp}\left(-{\left(\frac{t}{7.319}\right)}^{1.611}\right)\right)}^{exp\left(-1.94{\nu }_1^{{}^{\prime }}-0.6{\nu }_2^{{}^{\prime }}+0.58{\nu }_5^{{}^{\prime }}+0.7{\nu }_9^{{}^{\prime }}\right)}$
DT.1 (3rd layer)	24.600	2.339	$R_{\text{DT}.1{}_{\theta }}\left(t,{\nu }^{\prime }\right)={\left[1-2.040ln\left({\left(exp\left(-{\left(\frac{t}{24.6}\right)}^{2.339}\right)\right)}^{exp\left(-1.22{\nu }_2^{{}^{\prime }}+2.14{\nu }_5^{{}^{\prime }}+1.44{\nu }_6^{{}^{\prime }}\right)}\right)\right]}^{\raisebox{1ex}{$-1$}\!\left/ \!\raisebox{-1ex}{$2.040$}\right.}$
DT.2	22.271	0.969	$R_{\text{DT}.2}\left(t,{\nu }^{\prime }\right)={\left(\text{exp}\left(-{\left(\frac{t}{22.271}\right)}^{0.969}\right)\right)}^{exp\left(-0.64{\nu }_1^{{}^{\prime }}-0.68{\nu }_2^{{}^{\prime }}+0.65{\nu }_5^{{}^{\prime }}+0.26{\nu }_6^{{}^{\prime }}\right)}$
DT.3	44.742	1.012	$R_{\text{DT}.3}\left(t,{\nu }^{\prime }\right)={\left(\text{exp}\left(-{\left(\frac{t}{44.742}\right)}^{1.012}\right)\right)}^{exp\left(-0.44{\nu }_1^{{}^{\prime }}-0.82{\nu }_2^{{}^{\prime }}+0.28{\nu }_4^{{}^{\prime }}+0.87{\nu }_5^{{}^{\prime }}\right)}$
DT.4	14.549	1.301	$R_{\text{DT}.4}\left(t,{\nu }^{\prime }\right)={\left(\text{exp}\left(-{\left(\frac{t}{14.549}\right)}^{1.301}\right)\right)}^{exp\left(-1.08{\nu }_1^{{}^{\prime }}-0.98{\nu }_2^{{}^{\prime }}+0.29{\nu }_4^{{}^{\prime }}+0.66{\nu }_5^{{}^{\prime }}\right)}$
DT.5	30.569	0.988	$R_{\text{DT}.5}\left(t,{\nu }^{\prime }\right)={\left(\text{exp}\left(-{\left(\frac{t}{30.569}\right)}^{0.988}\right)\right)}^{exp\left(-0.6{\nu }_1^{{}^{\prime }}-0.65{\nu }_2^{{}^{\prime }}+0.35{\nu }_4^{{}^{\prime }}+0.45{\nu }_5^{{}^{\prime }}\right)}$
DT.6	28.420	1.012	$R_{\text{DT}.6}\left(t,{\nu }^{\prime }\right)={\left(\text{exp}\left(-{\left(\frac{t}{28.420}\right)}^{1.012}\right)\right)}^{exp\left(-0.68{\nu }_1^{{}^{\prime }}-0.57{\nu }_2^{{}^{\prime }}+0.82{\nu }_5^{{}^{\prime }}\right)}$

*PLP model: $\frac{a}{b}{\left(\frac{t}{b}\right)}^{a-1}$