Research Article

Multiobjective Dynamic Vehicle Routing Problem and Time Seed Based Solution Using Particle Swarm Optimization

Algorithm 1

TS-PSO.
Notations:
: Connected network graph; : Number of vehicles; : Number of static request; ST: Service time
CRV: Customer Request Vector; OV: Order vector; GR: Geographical Ranking; CRK: Customer ranking vector;
: Number of customers in th partition of network; : Number of dynamic request in th partition of network;
: Global best position of th generation; : Local best position of th particle in th generation
: Time horizon for th sub-networks; : th time seed of the th sub-network; ERT: Expected reachability time
: Threshold solution used for stopping criteria. Input- , , , . Output-
Process-
(1) Initialize a connected network .
(2) for   to // Generating CRV
(4) generate CRV (, PLDT, PUDT, STIL, STIU, ECPUT) randomly
(5) endfor
(6) for   to // Generating OV
(7)  generate GR vector (ADR, Dist., RN, SR) randomly and calculate Gr using (1)
(8)  generate CRK vector (VIC, IC, RC, CC) randomly and assign weight according to ranks
(9)  calculate ST using (2)
(10) calculate ERT using (3)
(11) endfor
(12) Partition   into sub-networks as
(13) for   to
(14)  Divide  time horizon into time seeds as
(15)  for each time seed
(16)   
(17)   for   to // Generating Customer Request Vector for Dynamic Requests
(18)    generate CRV (, PLDT, PUDT, STIL, STIU, ECPUT) randomly
(19)   endfor
(20)   for   to // Generating Customer Order Vector for Dynamic Requests
(21)    generate GR vector (ADR, Dist., RN, SR) randomly and calculate Gr using (1)
(22)    generate CRK vector (VIC, IC, RC, CC) and assign weight according to ranks
(23)    calculate ST using (2)
(24)    calculate ERT using (3)
(25)   endfor
(26)  
(27)  Generate  position and velocity for particle in th generation from COV
(28)  while  do
(29)   
(30)   for each particle , of the search space
(31)    evaluate fitness using objective function (5) as
(32)    if  (, , )
(33)       
(34)   endfor
(35)   
(36)   for   to number of particles in the swarm
(37)    if  , ,
(38)      
(39)   endfor
(40)  endwhile
(41)  store   for th time seed
(42)  endfor
(43) store  the set of for th partition
(44) endfor