Traffic data parameters

Handles queues of speed measures.

true: Clear queues in presence of hypocritical speed measures.

false: Otherwise

Default is true.

Defines the threshold to assess a speed measure to be a measure of congestion with respect to its ratio per the free flow speed.

When the measured speed is over CriticalSpeedRatio, the speed is hypercritical.

Default is 0.5.

Data type: UUID

Identifier of the customer.

It is used only for the communication with the MLF micro-service API.

Default value: Not applicable

Handles the generation of flow from speed measures, further than the corresponding capacity modification.

q(v) (link fundamental diagram, see ) is a very sensible function and in this case could produce very different results with very small parameter differences.

Furthermore, in the hypocritical branch of the fundamental diagram, q(v) is very steep. Therefore, to produce reliable results it requires a very good calibration of the link performances and very reliable speed measure data.

• 0 = Disable flow generation.
• 1 = Enable flow generation only if the speed measure is hypercritical.
• 2 = Enable flow generation.

Default is 0.

Handles the link entry capacity.

• true: Set the link entry capacity on hypercritical speed measure.
• false: Otherwise.

Default is false.

Sets a queue consistent with a hypercritical speed measure (see → Speed measure effects.).

• true: Run the algorithm QC when the speed measure is hypercritical.
• false: Run the algorithm FDC both for hypercritical and hypocritical speed measures.

Default is true.

Handles 0 values as missing values (not detected).

If IgnoreZeroValues is enabled, TRE ignores measures that have a value of 0.

This can be useful with some interfaces return 0 as an indication of missing data.

Admitted values:

• 0 = Do not ignore values of 0 in measures. This makes the model to set the flow (or any other state variables) equal to 0 during the correction due to the measure.

• 1 = Ignore values of 0 in measures.

Default is 1.

Effect of speed measures.

• 0 = No effect.

• 1 = Modify only the exit capacity. Sets the link exit capacity to a value equal to the flow corresponding to the speed measure on the link fundamental diagram.

• 2 = Full speed correction. It implies the effect of option 1. It also modifies the fundamental diagram of the link so that the speed of incoming vehicles is equal to the measurement at a flow value equal to the one that enters the connection in the model, in the initial instant of the measurement.

Default is 2.

The value of SpeedMeasEffect can have a relation with:

• HypercriticalSpeedMeasureSetQueue
• ClearQueueOnHypoSpeedMeasure
• The measured speed (MeasSpeed)

Based on the different combinations of the measured speed and the configuration parameters, can be run:

• FDC algorithm (see → Speed measure effects > Fundamental Diagram Correction (FDC)).
• QC algorithm (see → Speed measure effects > Queue Correction (QC): Hypercritical speed measure).

In case of SpeedMeasEffect=2:

Defines, through the pattern [yyyymmdd], the date of the traffic data to be imported.

Special values:

• −1 = Current simulation day.

Default is −1.

Defines the time extension, measured in seconds [s], of the validity of traffic states with respect to the input validity.

TrafficDataForecast defines the time extension of measures, producing an implicit forecast, assuming each measure to be valid for some additional time after the input end time.

Default is 900.

Defines a look ahead window, measured in seconds [s], when importing traffic data.

Traffic data has a creation date that describes the time when the data first becomes usable. Usually, only traffic data with a creation date prior to the current simulation time is taken into account.

TrafficDataLag extends the initial time interval of the simulation to include also traffic data not created at the beginning of the simulation.

This can be used if there is some component that provides data with some delay or that sets a time later than the expected time.

Default is 60.

Defines the accuracy threshold to accept traffic data.

The accuracy of traffic data is set in TSTA.ACCU (see → Real-time traffic data).

If TrafficStateMinAccuracy > TSTA.ACCU, the traffica data is discarded.

Special values:

0 :Accept all the data.

Default is 0.

Defines how the supply model behaves with respect to flow measures that are not associated to a corresponding speed measure during the same time interval.

Admitted values:

• 0 = The flow is always considered hypocritical and no queue can form on links with undetected speed data.

  It can lead to unrealistic behavior because any queue on a link is immediately deleted by a measure even if the measure is hypercritical.

• 1 = The flow is considered hypercritical if in the simulation the link is in spillback from downstream.

  The only drawback is an unrealistic queue behavior if in the simulation the downstream link takes an hypocritical entry state, because the queue on the monitored link suddenly vanishes.

• 2 = The flow is considered hypercritical if in the simulation the link is in (any) hypercritical state.

  It can lead to unrealistic behavior because once a queue has spilled back in the simulation, all measures are considered in congested conditions. Potentially, the queue might never disappear if the upstream demand in the model keeps to be higher than the measure even if it was actually hypocritical.

Default is 1.