VISSIM 5.30-05 User Manual

12 Dynamic Assignment
However, the use of the overlapping correction tends to assign more traffic to
longer routes in certain network situations. Although in general path
overlapping correction will improve the assignment quality, we recommend to
use the feature only in combination with restricting the differences in cost of
the allowed routes.
12.7.5 Dynamic Routing Decisions
When Dynamic Assignment is used, the vehicles in the network are on their
assigned routes and will ignore any standard routing decisions they come
across. Dynamic routing decisions are used to direct those vehicles that for
some reason must be rerouted. The idea behind is that a vehicle coming
across a dynamic routing decision checks whether a certain condition is
fulfilled at that moment, e.g. its destination parking lot is full. If the condition
is true for the vehicle a new parking lot choice or a new route choice is
computed according to a certain strategy. The strategy chosen defines which
parking lots are in the choice set.
In the Create routing decision window,
No. and Type have to be set.
In the Routes window, the condition
and strategy as well as additional
parameters (e.g. option Exclude full
parking lots) can be set for Routing
decisions of the Dynamic type, cf.
section 6.4.4.
634 VISSIM 5.30-05 © PTV AG 2011