The purpose of the Tools for Operational Planning (TOPl) project is to provide tools for quantative assessment of operational strategies designed to improve traffic conditions on congested freeways and surrounding arterials. The elements of such strategies are: demand management, which focuses on reducing excessive demand; incident management, which targets resources to alleviate accident hot spots; traveler information, which potentially reduces traveler buffer time; traffic control, which implements aggressive ramp metering at locations where significant reductions in congestion are likely to occur.

Macroscopic traffic models represent traffic as a compressible fluid in terms of flow, density and speed, as opposed to microscopic models which seek to reproduce the behavior of individual vehicle as its driver responds to its environment by changing its speed and lane. TOPl uses the well known macroscopic Cell Transmission Model (CTM).

CTMSIM is the interactive MATLAB based freeway traffic simulator of CTM. Simple and robust, CTMSIM has proved to be a handy tool for transportation researchers who can use it for evaluating ramp metering algorithms and for estimating the impact of different response times in the incident management. Its limitation is that it can only deal with a single freeway.

The Aurora object-oriented framework overcomes the limitations of the CTMSIM. Its basic objects, nodes and links, allow the user to construct heterogeneous road networks. Various event classes make it possible to generate simulation scenarios. The monitor objects can keep track of the state at selected nodes and links, coordinate control actions at nodes, or generate events at nodes or links when the monitored states reach certain thresholds.




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