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Regional Routing Model Review: C) Model Formulation and Scenario Analysis. Frank Southworth Oak Ridge National Laboratory Oak Ridge, TN 37831 NETS Program Review December 12, 2005 Washington DC. Calibration. Changes in Demands. Network Changes. Transit times, distances.

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Regional Routing Model Review: C) Model Formulation and Scenario Analysis

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Regional routing model review c model formulation and scenario analysis

Regional Routing Model Review:

C) Model Formulation and Scenario Analysis

Frank Southworth

Oak Ridge National Laboratory

Oak Ridge, TN 37831

NETS Program Review

December 12, 2005

Washington DC


Regional routing model review c model formulation and scenario analysis

Calibration

Changes in Demands

Network Changes

Transit times, distances

County/Port Based

Commodity Production

/Consumption Forecasts

County/Port Based

Mode/Route/Market

Choice Model(s)*

Changes to Network

Conditions (Capacities)

and Mode/Route Costs

Forecasting,

Scenario

Analysis

dollar/ton shipment rates

NETS Tier 1

Regional Economic

Activity Forecasts/

Scenarios

Mode Specific

Rate Estimation

Models

Forecast / Scenario Based

Commodity Flows, Costs

and Benefits

Fuel, labor, I&M costs

by vehicle /vessel types

(C,M,V) (Data)

Changes in Supply

Calibration, Forecasting & Scenario Analysis

Base Case Computed Flows, Costs (and Benefits)

* = Simultaneous or nested

mode and destination choice

linked to capacity constrained

route assignment


Regional routing model review c model formulation and scenario analysis

Estimate Commodity

Production (O) &

Consumption (D)

by Region

Estimate O-to-D Costs per Ton

Connect Os and Ds to Estimate

O-to-D Commodity Flows

Assign O-to-D Flows to

Modes & Routes

Iterate to

Convergence

Re-Estimate O-to-D Costs per Ton

Re-Estimate O-to-D Flows

The Basic Flow and Cost Estimation Process


Regional routing model review c model formulation and scenario analysis

Prototype Regional Routing Model Formulation:

+ m 1/ βm ( Xi jm ln Xi jm) + m 1/ λm ( Xi jkm ln Xi jkm)

subject to:

Vak = ∑i ∑j ∑r δ i,j akr X i j kr for all links, a, and modes k, in the network

∑rX i j rk = X i j k for i=1,2,...I, and j=1,2,...J

∑kX i j k = X i j for i=1,2,...I, and j=1,2,...J

Vak ≥ 0

X i j kr ≥ 0

V = a link volume

X = an O-D flow volume

S = link transportation time or

generalized cost


Regional routing model review c model formulation and scenario analysis

i j m ] Aim Bjm

Xi jm = Oi m Dj m F[ βm,

* m

 i j ( Xi jm di j m } /  i,j Xi jm =

Freight Destination Choice (Flows Modeling):

where

i j m ]} for all i

Aim = 1/{j Bjm Djm F [ βm,

Bj m = 1/{i Aim Oim F [ βm, i j m ]} for all j

and


Regional routing model review c model formulation and scenario analysis

c ijm

= -(1/ λm ) ln {k exp (-λm c i j km )}

Freight Mode Choice:

Xijkm = Xijm *[exp(-θm ckm)/ ∑kεK(m) exp(-θm ckm)]

where (for example):

cijkm = α0 + α1 rijkm + α2 Sijkm + α3 vijkm

and,

(links mode and destination choice)


Regional routing model review c model formulation and scenario analysis

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


Regional routing model review c model formulation and scenario analysis

Lock Congestion Function

19

2000

2000

18.5

1800

1800

18

1600

1600

17.5

S = S0 * (1+ 0.15 (V/C)**4)

1400

1400

S = k /((C/x)

1)

17

1200

1200

S=Travel Time (Minutes)

16.5

S= Minutes of Delay/Tow

1000

1000

16

800

800

15.5

600

600

15

400

400

14.5

200

200

k

k

14

0

0

5

5

10

10

15

15

20

20

25

25

30

30

35

35

40

40

45

45

50

50

0

500

1000

1500

2000

C/2

C/2

C

C

Traffic Volume (Vehicles/hour)

x =Kilotons/Year (in thousands)

Network Link Transit Time (Congestion) Functions

Highway Congestion Function

“Generic” link congestion function for use in Toy Model:

Sa = Sao * [ 1 + θ1* Va + θ2 *( Va / Capa)γ ]


Regional routing model review c model formulation and scenario analysis

Generalized Transportation Costs (Shipper Perspective)

Level 1: (Statistical)

Freight Rates In-Transit Times Service Quality (Reliability)

Level 2: (Engineering)

Variable Operating Costs (Annualized)

Capital Operating Costs

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

Components of Freight Movement Costs


Regional routing model review c model formulation and scenario analysis

35

41

Port C

36

38

37

10

33

8

2

39

7

32

42

44

11

27

29

16

25

Port B

12

Lock c

Lock b

1

14

43

28

23

26

9

15

24

13

40

3

Port A

6

17

Lock a

31

34

18

30

19

Key:

20

Network Nodes (44)

40

5

Traffic Centroids

(10 in all)

4

21

Links (110 in all):

22

Truck

Rail

Inland Water

Deep Water


Regional routing model review c model formulation and scenario analysis

7

8

2

9

1

3

6

4

5


Regional routing model review c model formulation and scenario analysis

Model Run # 1

Origin Mode Split = 36.7% water

63.3 % rail


Regional routing model review c model formulation and scenario analysis

Model Run # 2

Origin Mode Split = 74.9% water

25.1% rail


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