Dynamic Origin-Destination Matrix Estimation Based on Urban Rail Transit AFC Data: Deep Optimization Framework with Forward Passing and Backpropagation Techniques
Table 1
Sets, indices, variables, vectors, and parameters.
Definitions
Indices
i
Index of nodes (origin stations),
j
Index of destination stations,
t
Index of departure time intervals,
Index of travel time,
p
Index of paths,
Sets
N
Set of stations (origin stations)
D
Set of destination station indices
Set of destination station indices for the departure time t
T
Set of departure time indices
Set of departure time indices for the origin station i
Set of departure time indices from the origin station i to the destination station j
Set of travel time indices
Set of travel time indices for the path p
P
Set of path indices
Set of path indices for the destination station j
Set of path indices from origin station i to the destination station j at departure time t
Variables
Number of passengers entering (tap-in) the system at origin station i
Number of passengers departing at time t
Number of passengers exiting (tap-out) the system at destination station j
Number of passengers choosing the path p
Number of passengers spending the travel time
Vectors
X
The vector of the input layer,
The vector of hidden layer 1,
The vector of hidden layer 2,
The vector of hidden layer 3,
Y
The vector of the output layer,
Parameters
The proportion of passengers departing at time t to the passengers entering (tap-in) the system at node i
The proportion of passengers exiting (tap-out) the system at node j to the passengers departing at time t
The proportion of passengers choosing the path p to the passengers exiting (tap-out) the system at node j
The proportion of passengers with the travel time to the passengers choosing the path p
Learning rate
A gradient of hidden layer 1
A gradient of hidden layer 2
A gradient of hidden layer 3
A gradient of the output layer
The updated value of
The updated value of
The updated value of
The updated value of
The matrix of the departure time layer proportion
The matrix of the destination station layer proportion
The matrix of the path layer proportion
The matrix of the travel time layer proportion
Number of real passengers spending the travel time from AFC records