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Oregon statewide integrated model
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Select Link Start Time Post Processor #151

Open bettinardi opened 8 months ago

bettinardi commented 8 months ago

The CT start time is becoming problematic for MPO external model use. In SWIM 2.5 the percentage of "local" truck trips was much greater and masked the issue of long distance trips having trip start times that were much different from the time they entered the MPO model area. No with a higher relative percentage of long-haul trucks (less local short distance trucks overall) the issue is much more apparent.

The proposed solution is to build a "trip start time" post-processor. After the select link cut is performed and a resulting sub set of trip tables output, the cut trip tables can then have their trip start times processed to account for the travel time from the origin zone to the select link location.

A simple method might be to profile the travel time for trips identified using that external station, and to take the minimum or near minimum OD travel time for trips using that station. That minimum travel time could be used as follows:

Post-Processed External Station trip start time = Original trip start time + total travel time of the trip - minimum (or something close to minimum, like 25th percentile) travel time of trips tagged with that external station

A simple method like this would allow the start time to be adjusted with no further information. A more complex method would be to use a node to zone level path analysis from Visum and determine the modeled travel time from the external station to the zone of interest and to calculate the modeled time that the trip would be estimated to cross the boundary, using Visum's path analysis. I would propose that to be overly complicated, and a simple trip analysis of the shortest trips using the external station would likely be close enough to bin flagged trips in the correct time of day.

bettinardi commented 7 months ago

As we are adding time to the post-processor. Consider mandatory hour of service and required start time (10 hour break, after 11 hours of driving). After ~10 hours of driving they start to look for parking which is very difficult. In Oregon you can drive for 12 hours if it's all within Oregon (intra-state).

bettinardi commented 2 months ago

As a reminder to Alex - the work script to finalize (and close this issue) is here: \s6000e\6420only\Statewide\Tools\SWIM\SWIM_26\ModelApplication\ExternalModels\BRM\26SL_Results

bettinardi commented 2 months ago

Current thought on how to address this issue: For SWIM assignment (demand matrix creation), we should use the mid point time (start time + arrival time / 2). For select link (external model) pulls, we should have a processor that updates the start time or some new assign time for trips that end in the region with something like the script that I reference above.

jfdman commented 1 month ago

I like the method of calculating the time as start time + truck travel time from skim from origin to external station TAZ as proposed above. That does not seem very complicated to calculate.

bettinardi commented 1 month ago

I think your approach would be ideal if we could think about how to determine that information in an automated way. I'm trying to reduce the user inputs and have the model just get pretty close with no extra information provided. So if we can do a shortest path (node-node) search in Visum in an automated way that might do what you are thinking of.