Table 15 Explanations of variables in... | Emerald Publishing

Table 15

Explanations of variables in Equations 1 and 2 (1/2)

Variable	Explanation	Equation/comment
C _pi-i	Preventive intervention costs	$\sum_{o}^{O} \sum_{s}^{S} (e_{pi-o}^{s} \times {uc}_{pi-o}^{s})$
C _pi-tt	Travel time costs due to preventive interventions	$\sum_{o}^{O} \sum_{i}^{I} (t_{pi-o} \times v \times p \times att \times {uc}^{tt})$
C _pi-a	Accident costs due to preventive interventions	0
R _f-i	Corrective intervention risks (i.e. probability of failure multiplied by the costs of corrective interventions)	$\sum_{o}^{O} \sum_{s}^{S} (p_{f-o}^{s} \times e_{ci-o} \times {uc}_{ci-o})$
R _f-tt	Travel time risks (i.e. probability of failure multiplied the additional travel time costs)	$\sum_{o}^{O} \sum_{s}^{S} (p_{f-o}^{s} \times t_{f-o} \times v \times p \times att \times {uc}^{tt})$
R _f-a	Accident risks (i.e. probability of failure multiplied by the conditional probability of accident given a failure and the number of people on the train multiplied by the accident risks conditional on a failure)	$\sum_{o}^{O} \sum_{s}^{S} p_{f-o}^{s} \times p_{a-f} \times p \times (p_{a-pd} \times {uc}_{a-pd} + p_{a-inj} \times {uc}_{a-inj} + p_{a-fat} \times {uc}_{a-fat})$
att	Additional travel time per train	20 min/d – assumed to be constant for all interventions
e _ci-o	Extent of object o in state s to have a corrective intervention	Calculated using transition probabilities in Tables 10 and 11 and the strategies in Table 14
$e_{pi-o}^{s}$	Extent of object o in state s to have a preventive intervention	Calculated using transition probabilities in Table 10 and the strategies in Table 8

Variable	Explanation	Equation/comment
C _pi-i	Preventive intervention costs	$\sum_{o}^{O} \sum_{s}^{S} (e_{pi-o}^{s} \times {uc}_{pi-o}^{s})$
C _pi-tt	Travel time costs due to preventive interventions	$\sum_{o}^{O} \sum_{i}^{I} (t_{pi-o} \times v \times p \times att \times {uc}^{tt})$
C _pi-a	Accident costs due to preventive interventions	0
R _f-i	Corrective intervention risks (i.e. probability of failure multiplied by the costs of corrective interventions)	$\sum_{o}^{O} \sum_{s}^{S} (p_{f-o}^{s} \times e_{ci-o} \times {uc}_{ci-o})$
R _f-tt	Travel time risks (i.e. probability of failure multiplied the additional travel time costs)	$\sum_{o}^{O} \sum_{s}^{S} (p_{f-o}^{s} \times t_{f-o} \times v \times p \times att \times {uc}^{tt})$
R _f-a	Accident risks (i.e. probability of failure multiplied by the conditional probability of accident given a failure and the number of people on the train multiplied by the accident risks conditional on a failure)	$\sum_{o}^{O} \sum_{s}^{S} p_{f-o}^{s} \times p_{a-f} \times p \times (p_{a-pd} \times {uc}_{a-pd} + p_{a-inj} \times {uc}_{a-inj} + p_{a-fat} \times {uc}_{a-fat})$
att	Additional travel time per train	20 min/d – assumed to be constant for all interventions
e _ci-o	Extent of object o in state s to have a corrective intervention	Calculated using transition probabilities in Tables 10 and 11 and the strategies in Table 14
$e_{pi-o}^{s}$	Extent of object o in state s to have a preventive intervention	Calculated using transition probabilities in Table 10 and the strategies in Table 8