Table 1 Notations of a mathematical model.

From: A learning-driven algorithm for maintenance team and UAV collaboration in restoring power network

Input variables

F

The set of faulty nodes, where \(|F|=n\)

\(F^{\prime }\)

The set of unknown faulty nodes, where \(|F^{\prime }|=n^{\prime }\) and \(F^{\prime } \subseteq F\)

\(h_{i}\)

The i-th maintenance team, \(i=1,2, \ldots , m_{1}\)

\(u_{i}\)

The i-th UAV, \(i=1,2, \ldots , m_{2}\)

\(\tau _{u_{i}, f_{j'}}\)

The detection time for detecting the unknown faulty node \(f_{j^{\prime }}\)

\(p_{u_{i}, f_{j'}}\)

The probability of \(u_{i}\) accurately detecting the unknown faulty node \(f_{j^{\prime }}\)

\(\tau _{h_{i}, f_{j}}\)

The repair time to restore the faulty node \(f_{j}\)

\(\eta ^{+}\)

A coefficient of \(\tau _{h_{i}, f_{j}}\) when \(f_{j}\) is not accurately detected by UAV, \(\eta ^{+} \in [1.3,1.5]\)

\(\eta ^{-}\)

A coefficient of \(\tau _{h_{i}, f_{j}}\) when \(f_{j}\) is accurately detected by UAV, \(\eta ^{-} \in [0.6,0.8]\)

\(\delta\)

The fatigue factor of maintenance-team

\(t_{u_{i}, 0, f_{j'}}\)

The flight time of \(u_{i}\) from its starting point to \(f_{j'}\)

\(t_{u_{i}, f_{j'}, f_{k'}}\)

The flight time of \(u_{i}\) from \(f_{j'}\) to \(f_{k^{\prime }}\)

\(t_{h_{i}, 0, f_{j}}\)

The travelling time of \(h_{i}\) from operation centre to \(f_{j}\)

\(t_{h_{i}, f_{j}, f_{k}}\)

The travelling time of \(h_{i}\) from \(f_{j}\) to \(f_{k}\)

Decision variables

\(\pi _{u_{i}}\)

The unknown faulty node scheduling sequence of \(u_{i}\)

\(\pi _{h_{i}}\)

The faulty node scheduling sequence of \(h_{i}\)

\(\pi =(\pi _{u}, \pi _{h})\)

A solution for the considered problem, where \(\pi _{u}=\{\pi _{u_{1}}, \pi _{u_{2}}, \ldots , \pi _{u_{m_{2}}}\}\) and \(\pi _{h}=\{\pi _{h_{i}}, \pi _{h_{2}}, \ldots , \pi _{h_{m_{1}}}\}\)