The Value of Preemptive Pick-Up Services in Dynamic Vehicle Routing for Last-Mile Delivery: Space-Time Network-Based Formulation and Solution Algorithms
Table 2
Sets, indexes, and parameters for model establishment.
Symbol
Definition
O
Index of depot
P
Set of physical nodes in physical network
N
Set of nodes in physical network,
E
Set of directed links in physical network
T
Set of time stamps
K
Set of vehicles
Set of space-time vertexes
Set of space-time arcs
Set of space-time arcs for vehicle
Set of space-time traveling arcs
Set of space-time serving arcs
Index of decision epoch
Index of vehicles
Index of physical nodes
Set of physical nodes that still have to-be-served requests until time
Set of to-be-served request nodes until time
Set of to-be-served request nodes generated from physical node until time
Set of arriving arcs that end at request node in vehicle ’s network
Origin of vehicle at time
Destination of vehicle
The request node generated at physical node until time
EDT
The earliest departure time from depot
LAT
The latest arrival time back to depot
Required service duration for request node
Required service duration for physical node
Remaining service duration for physical node until time
