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Regional Routing Model Review: C) Model Formulation and Scenario Analysis Frank Southworth Oak Ridge National Laboratory Oak Ridge, TN NETS Program Review December 12, 2005 Washington DC

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Calibration, Forecasting & Scenario Analysis County/Port Based Mode/Route/Market Choice Model(s)* Calibration Forecast / Scenario Based Commodity Flows, Costs and Benefits Forecasting, Scenario Analysis * = Simultaneous or nested mode and destination choice linked to capacity constrained route assignment Base Case Computed Flows, Costs (and Benefits) County/Port Based Commodity Production /Consumption Forecasts NETS Tier 1 Regional Economic Activity Forecasts/ Scenarios Changes in Demands Fuel, labor, I&M costs by vehicle /vessel types (C,M,V) (Data) Changes to Network Conditions (Capacities) and Mode/Route Costs Network Changes Mode Specific Rate Estimation Models Transit times, distances dollar/ton shipment rates Changes in Supply

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Estimate Commodity Production (O) & Consumption (D) by Region Connect Os and Ds to Estimate O-to-D Commodity Flows Assign O-to-D Flows to Modes & Routes Re-Estimate O-to-D Costs per Ton Estimate O-to-D Costs per Ton Re-Estimate O-to-D Flows Iterate to Convergence The Basic Flow and Cost Estimation Process

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY + m 1/ β m ( X i j m ln X i j m ) + m 1/ λ m ( X i j km ln X i j km ) Prototype Regional Routing Model Formulation: subject to: V ak = i j r δ i,j akr X i j kr for all links, a, and modes k, in the network r X i j rk = X i j k for i=1,2,...I, and j=1,2,...J k X i j k = X i j for i=1,2,...I, and j=1,2,...J V ak 0 X i j kr 0 V = a link volume X = an O-D flow volume S = link transportation time or generalized cost

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Freight Destination Choice (Flows Modeling): X i j m = O i m D j m F[ β m, i j m ] A i m B j m A i m = 1/{ j B j m D j m F [ β m, i j m ]} for all i B j m = 1/{ i A i m O i m F [ β m, i j m ]} for all j i j ( X i j m d i j m } / i,j X i j m = * m where and

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Freight Mode Choice: X ij km = X ij m *[exp(-θ m c km )/ kεK(m) exp(-θ m c km )] c ij km = α0 + α1 r ij km + α2 S ij km + α3 v ij km where (for example): and, c ij m = -(1/ λ m ) ln { k exp (-λ m c i j km )} (links mode and destination choice)

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Components of Freight Costs that Need Modeling: Number of different legs to a journey Shipper/receiver perceived costs per leg: freight rate transit time service reliability Congestion effects i.e. congestion transit time and reliability direct plus indirect (i.e. rate) effects on costs

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY S=Travel Time (Minutes) Traffic Volume (Vehicles/hour) S = S0 * ( (V/C)**4) Highway Congestion Function S a = S ao * [ 1 + θ1* V a + θ2 *( V a / Cap a ) γ ] Generic link congestion function for use in Toy Model: Network Link Transit Time (Congestion) Functions

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Components of Freight Movement Costs Freight Rates In-Transit Times Service Quality (Reliability) Variable Operating Costs (Annualized) Line-haul costs Loading/unloading costs Equipment utilization costs Commodity carrying costs Administrative costs Shipment distance Cargo type (commodity, weight, volume) Labor rate Fuel price Carrier/operator type Equipment type Company type (private/for-hire; size) Contract type (duration) Facility type, Location, Operating licenses, fees and taxes Capital Operating Costs Generalized Transportation Costs (Shipper Perspective) Level 1: (Statistical) Level 2: (Engineering)

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Port A Port B Port C Lock a Lock b Lock c Truck Rail Inland Water Deep Water Traffic Centroids (10 in all) Network Nodes (44) Key: Links (110 in all): 44 43

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Model Run # 1 Origin Mode Split = 36.7% water 63.3 % rail

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Model Run # 2 Origin Mode Split = 74.9% water 25.1% rail

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O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY

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