4.2 Parametric Description, 1jxi i

4.2 Parametric Description
, 1
j
xi i : The mode of transportation between nodes i and i 1 , , 1 j 0,1
i i x , 1 means that the mode j is
selected between i and i 1, while 0 means not.
Make j 1: road transportation;
j 2 : railway transportation;
j 3: waterway transportation;
j,k
i y : j,k 0,1
i y , 1 means that the mode shift from j to k in node i , 0 means there is no mode shift in node
i ;
, 1
j
i i c : The unit price of mode j between nodes i and i 1;
, 1
j
i i : The proportion of the total transport volume in mode j between nodes i and i 1, if there is only one
transportation mode, , 1 j 1
i i ;
j,k
i e : The transfer fees of the mode shift from mode j to k in node i , including loading and unloading costs,
carrying costs and the warehouse cost which proportional to the waiting time, etc;