Overview - bellevuewa/BKRCast GitHub Wiki
This section contains following sub-sections:
Region
The BKRCast model region aligns with the PSRC region but incorporates a specific BKR zone system and networks. This zone system features more zones within the BKR region and fewer in the rest of the PSRC region, designated as External BKR. The current zone system comprises 1,181 active internal BKR zones, 125 external BKR zones, and 18 external stations. Additionally, it encompasses 134 park-and-ride locations and 4 special generators. All special generators are situated outside the BKR area.
BKRCast operates with eight modes. They are SOV, HOV2, HOV3+, Transit walk access, Transit auto access, bike, walk, and truck.
Travel is categorized into seven purposes: Work, social, shop, school, personal business, meal, and escort.
A zoomed-in view of the BKR region:
Networks
The BKRCast model contains highway and transit networks. The highway network comprises 55K+ links and 22K+ nodes.
The transit network is characterized by 600+ transit lines with more than 6100 stops in the model region.
Model System
The BKRCast model package is comprehensive, encompassing all estimated and calibrated demand models along with the necessary scripts for assigning demand to both road and transit networks. The demand models, illustrated in the figure below, leverage inputs such as land use, demographics, and network data to generate trip tables categorized by user class and time of day. These trips, constituting the 'demand', are subsequently assigned to transportation network using INRO's Emme software.
In the event that network assignment hasn't reached equilibrium, cost and time skims are relayed back to the Daysim demand model. This iterative process enables the production of updated trip tables, incorporating the latest network conditions from the ongoing model iteration. The model continues this cycle until convergence is achieved, a point defined by the suer in the configuration file. The culmination of the process involves the generation of reports summarizing the model outputs.
