Vehicle Generation

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Vehicle Entry Headway Distribution Two types of vehicle entry distributions can be specified: Uniform or Random. For a uniform distribution, each vehicle will enter at the same headway, i.e., 3600 s/h divided by the entry volume (in veh/h). For example, an entry volume will result in a vehicle entering the network every 2 seconds. If the ‘Random’ distribution type is selected, two different distributions will be used, as follows:
 * Entry flow rate < 900 veh/h &#8594; Negative Exponential distribution
 * Entry flow rate ≥ 900 veh/h &#8594; Normal distribution
 * The standard deviation for the Normal distribution is calculated as: (Average Headway × Number of Lanes - MinArrivalHeadway) / 2.5
 * The minimum arrival headway is calculated as: DesiredHeadwayMultiplier × 1.1 + (StopGap + MinVehLength) / DesiredSpeed

Vehicle Fleet Types
 * Small Auto
 * Large Auto
 * Small Truck
 * Large Truck