Travel Demand Air Quality Model

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Travel Demand / Air Quality Model
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Travel Demand And Air Quality Model Flowchart
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Model Area

• Include OKI and MVRPC Regions
• 1,608 zones in OKI Region
• 817 zones in MVRPC Region
• 63 external stations in OKI Region
• 43 external stations in MVRPC Region

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Zone Map
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Trip Purposes

• Home-based work (HBW)
• Home-based university (HBU)
• Home-based other (HBO)
• Home-based school transit (HBSC)
• Truck
• External-internal (EI)
• External-external (EE)

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Trip Generation

• Cross Classification Models (HBW, HBU, HBO, HBSC,
  NHB)
• Regression Equations (EI)
• Trip Tables (EE, Truck)
• Daily Trips

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Trip Distribution

• Gravity Models
• Peak and Off-Peak Models for HBW, HBU, HBO, NHB
• Daily model for EI
• Growth Factoring Models for HBSC, TRUCK, EE

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Modal Choice

• Nested logit Models for HBW, HBU, HBO, NHB
• Peak and Off-Peak Models
• Modes
• Auto modes Drive alone, Shareride2, Shareride3
• Transit modes Walk to local bus, Walk to
  express bus, Walk to urban rail, Walk to commuter
  rail, Drive to local bus, Drive to express bus,
  Drive to urban rail and Drive to commuter rail

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Modal Choice Nesting Structure
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Transportation Mode Utility

• Utility is a function of in-vehicle time
  (driving/riding), out-vehicle time (waiting /
  transfer / walking), travel cost (auto operating
  cost, parking cost and transit fare)

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Market Segmentation

• For HBW
• 0 car, cars lt workers, carsworkers, cars gt
  worker
• For HBO
• 0 car, 1 car, 2 cars, 3 and 3 cars

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Highway Assignment

• Equilibrium assignment procedure
• Travel time and travel cost
• Roadway capacity
• Assign Drive Alone, Shareride2, Shareride3,
  Single unit truck, Multiple unit truck separately
• Assign trips by 4 time periods

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Transit Assignment

• All or nothing assignment procedure
• Riding time, waiting time, access time (walk or
  driving)
• Assign sub-mode trips separately
• Assign peak and off-peak trips separately

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Emission Calculation Flow Chart
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VMT Distribution Calculation
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VMT Distribution Calculation
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Explanation of Variables
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Explanation of Variables
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Speed-Volume Relationship Equations
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Emission Factor and Emission Calculation
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FreeFlow Speed Calculation
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FreeFlow Speed Calculation
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FreeFlow Speed Calculation
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Explanation of Variables
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Classified FreeFlow Speeds
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Classified FreeFlow Speeds
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Classified Roadway Capacities
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Classified Roadway Capacities