Environmental Engineering Reference
In-Depth Information
Table 5
(continued)
Description
Application
Type/Collection
methods
Strengths
Weakness
Vehicle based
Individual vehicles as
the sampling unit.
Collect: origin,
destination, trip
mileage, travel time,
routing, purpose,
time of day,
commodity,
shipment size, truck
type, land use,
activity at trip end
Trip chaining, trip
generation, and trip
routing
Travel diaries. Collect
travel diaries for a
period of time from a
sample of trucks
operating in the
region
Useful for
understanding
internal-internal
truck trips in an
urban area
Difficult sampling
process. Using
vehicle registration
samples may
produce biased
results. Low
response rates
Assisted by Global
Positioning System
(GPS) to track the
routing patterns
inside he study area
Spatial/temporal
movement data
could be collected;
real time data
Global Positioning
Systems(GPS)
cannot provide the
data collected by
traditional surveys
Tour based
Focus on data collection
along the supply
chain. Individual
shipments are tracked
long a supply chain
Use shipments as
measurements units.
Capture economic
relations vital for
transport policy
Longitudinal surveys:
individual shipments
are tracked long a
supply chain
Provides a
comprehensive
description supply
chains. Tracks
each shipment
from shipper to
final receiver
Expensive, budget may
condition their
success or failure.
Requires a very
specific survey
design
Trip intercept based
Focus on truck/vehicle
trips. Collect: routing
patterns, Origin-
Destination(OD)
locations,
commodity/truck
type, weights,
shipper/receiver/
carrier data
Freight modeling an
planning applications
Roadside Interviews
Low costs. High
response rates.
Best statistical
control and
reliability. Capture
trucks entering/
existing and
passing through
the study area
Limited locations may
lad to sampling bias.
Potential traffic
disruption. Cannot
collect tours data.
Not effective for
internal-internal
truck traffic data
(continued)
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