SCOOT Version 4.5In addition to the facilities provided in previous versions, V4.5 has the following new developments:
- Enhanced bus priority logic - differential priority
Differential priority refers to providing priority on the basis of criteria other than vehicle class alone, such as adherence to schedule. Bus management systems monitor the position of individual buses and their adherence to schedule. If a 'degree of lateness factor' is provided to SCOOT, SCOOT is then able to provide different levels of priority according to how late a bus is. The advantages of this approach are that by providing priority to late buses only, and hence to fewer buses, a higher level of priority may be given and the disbenefit to other traffic reduced. It should also lead to a greater improvement in the regularisation of the service and hence the waiting time of passengers will be reduced.
- Enhanced gating logic
In Version 4.5 the logic has been enhanced to make it more controllable by the traffic engineer and to allow more gradual application; a little restraint at the first signs of trouble, then increasing the restraint as the undesirable level of traffic spreads to further links in the protected area.
- Logic to allow emissions to be taken into account by the SCOOT optimisers
The SCOOT kernel has been modified so that the user can choose the objective function used in the offset optimiser. It can be changed from the normal one of a weighted sum of delays and stops to the weighted sum of estimated emissions.
- Improved validation
New messages have been added to SCOOT to assist with validation, which should reduce the time needed for this process.
- Supplementary detectors
Logic to allow detector information from supplementary detectors to be either added to or subtracted from the normal SCOOT detector.
- Option of removing node from cycle optimiser decision at cycle times above its required minimum cycle time
If this option is set the cycle time optimiser will not consider the advantage of increasing the cycle time to allow the node to double cycle.
- Improved control of filter links in busy conditions
- Improvements to the split optimiser if a demand-dependent stage is not called
SCOOT can optimise which of the alternative stages should receive the extra green time available because the demand-dependent stage has not been called.