Trans Sys Chap04

8/9/2019 Trans Sys Chap04

1/27

Introduction toTransportation

Systems

1


2/27

PART I:CONTEXT,

CONCEPTS ANDCHARACTERIZATION

2


3/27

Chapter 4: The Customer andLevel-of-Service

3


4/27

The Customer u The customers of the transportation

system, be it the air passenger or the

coal executive who is deciding which

railroad to use to service his

transportation needs, is fundamentalto the transportation enterprise.

u Thinking about what is important tothe customer, from the perspective ofwhat services transportation

organizations provide, is fundamental.

4


5/27

The Customer u Hamel and Prahalad, in Competing

for the Future, define the market

opportunity as fundamental to the

transportation enterprise.u Drucker talks about allresults being

externalto the organization, and the

purpose of the business being thecreation of customers.

5


6/27

Two Kinds of TransportationCustomers

u Freight Transportation Customersu Traveler Transportation Customers

6


7/27

Supply Chain ManagementThe transportation provider -- the

railroad, for example -- becomes an

integral part of the customers

logistics system, providing reliable

delivery and pick-up of goods asthey progress through the supply

chain.

7


8/27

Different Kinds of FreightRequiring DifferentLevels-of-Service

u High-value manufactured goods......

u Bulk commodities (e.g., coal, agriculturalproducts)

8


9/27

Level-of-Service Variablesfor Freight

FPRICEFTRAVEL TIMEFSERVICE RELIABILITYFAVAILABILITY OF SPECIALIZED

EQUIPMENTFPROBABILITY OF LOSS AND

DAMAGE

9


10/27

Modes, Services andCustomers

Different Customers

Different ServicesRequired by

a Single Customer

Different Modes/CarriersProviding DifferentLevels-of-Service

Figure 4.210


11/27

U.S. Freight Transportationin 1993MODE % of

TON-MILESRAILROAD 34.8

TRUCK 24.5

WATER 21.9

PIPELINE 18.5

AIR 0.3

But this may differ substantially from

country to country.

11


12/27

Traveler TransportationCustomers

u Urban traveler transportationu Intercity traveler transportationu International transportation

12


13/27

Trip Purposesu Schoolu Jobu Social Activitiesu Medical needs

.

.

.

13


14/27

ModesuAutomobile/Highwayu Bus/Highwayu RailroadsuAiru Ships/Ferries

14


15/27

Level-of-Service Variablesfor Travelers

u Priceu Travel Timeu Service Frequencyu Comfortu Reliability

15


16/27

Customer Choice Customers (freight or traveler)

have choices of modes.

They make these choices based

on the level-of-service provided bycompetitors.

16


17/27

Level-of-service (LOS) is a

complex, multidimensionalconcept. The transportation

provider needs to understand LOS,

as his/her customer perceives it.

17


18/27

Level-of-Service asDynamic

The level-of-service provided bythe carrier will change as a

function of the volume being

carried by that carrier.

18


19/27

But, do customers drive service

decisions? We would hope so, but

not always.

An old joke: We would be better

able to keep our buses on

schedule if we didnt have to stopfor passengers.

19


20/27

u Federal Express determined thatpeople put a high value oninformation about their shipment.

u People want to buy the reliability andthe travel time, but they also want to

buy information.u Knowing when their parcel is going to

get there and knowing if it has goneastray is valuable information to thecustomer. (Its also valuable toFederal Express!)

20


21/27

Reducing Multi-DimensionalLevel-of-Service to aUni-Dimensional Variable

variables unitsTRAVEL TIME tt MINUTES

ACCESS TIME t MINUTESaWAITING TIME t MINUTESwFARE F $

COMFORT H HUGS

21


22/27

UtilityLets define a variable V, which is

the utility of a traveler choice inutils:

V= a0 + a1tt + a2t + a3t + a4F + a5Ha wNow, if high utility is superior, what

is the sign ofa1, a2, a3, a4 and a5? Iseach one positive or negative?

22


23/27

Mode Choice

Suppose we have three possible modes of travel

from Boston to New York -- air, train, auto -- and

you could measure each of the level-of-service

variables for each mode. We could compute the

utility of each mode,

Vair, V

train, V

autoand you could assume that the mode with the

highest utility is the one you would choose.

23


24/27

Mode Choice

However, much modern literature in utility theory uses a

probabilistic approach. For example, the probability a traveler

selects the air mode is as follows:

VairP(air) =Vair+ Vtrain+ Vauto

or perhaps:

Vair

eP(air) =

eVair+ eVtrain + eVauto

Mode Choice

This probabilistic approach is intended to reflect the fact that:

1) people have different utilities, and 2) perhaps we have notcaptured all the level-of-service variables in our formulation.

If we know the overall size of the market, we can approximate

the mode volumes by multiplying market size by the probability

a particular mode is selected.24


25/27

variability

time

Average time =

Figure 4.6

(time)

Charlestown Route

time

Average time =

25Figure 4.7

Travel Time Reliability

This depends on the in travel time

between origin and destination.

Tunnel Route

30 minutes

(time)

40 minutes


26/27

u Now, comparing these two distributions, theaverage travel time going through the

tunnel is lower than the average travel time

avoiding the tunnel. If we were making thedecision based on average travel time, we

would pick the tunnel route.

u But if we had a plane to catch we mightsay, If I am virtually assured of getting tothat plane by taking the higher average but

lower variation route, that is what Im going

to do.

u So, I chose the more reliable -- lowervariation route -- higher average travel time

route, because it virtually assures me

making my air connection.26


27/27

Reliability

We will call variability in travel time

servicereliability. In particular systems,service reliability in travel time can be as

important as average travel time.

Railroad and truck systems for moving

freight differ both on a reliabilitydimension and on an average travel time

dimension.

27

Date post:	30-May-2018
Category:	Documents
Upload:	dr-ir-r-didin-kusdian-mt
View:	221 times
Download:	0 times

Trans Sys Chap04

Documents