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management mode, type of vehicles used, distance covered, number of delivered
establishments, running time, parking place and parking time). The urban goods
movements are directly linked with the type of activity, the number of deliveries
and pickups, the operation structure, the management mode and the organizational
mode.
The main relationships are the following:
• between management mode and organization mode (own account mostly carries
out direct trips, third part transport uses rounds);
• between type of vehicle and management mode (own account uses more light
commercial vehicles, third party transport uses trucks);
• between distances covered and management mode and organization modes (the
rounds of third party transport are longer than those of own account);
• between the distance covered between 2 stops and the size of the round (the
longer the round, the shorter the distance between two stops);
• between stop timing and round size (the more stops on the round, the shorter the
delivery time).
A very important result is that the same relationships was observed in the three
cities surveyed: the comparison of the results of the three French freight transport
surveys highlighted a notable similarity in terms of the diagnostic, the number of
deliveries generated by each type of activity, and inside each class of activity the
number of deliveries performed by type of vehicles, the share of own account, and
the share of the different types of rounds. This demonstrates that for each class of
activity, the overall economic and logistic structure takes precedence over the size
and the shape of the cities. This result permits transposing the knowledge deriving
from these surveys to other cities and building a general model applicable for
French and other European cities.
4.2 Modelling Methodology
The results of the survey were used to build the Freturb IEM estimation model.
The main hypothesis of the model is that the number of pickups or deliveries at a
given establishment depends on its activity (French NACE code), its size and its
nature. Therefore, the model is based on the nature of the generators (shippers,
forwarders, consignees) and the transport choices carried out by the latter. More
precisely, the model is organized as follows:
• First, the number of movements (pickup or delivery operations) is generated at
each establishment, before being grouped by each zone.
• Second, round movements are characterized (main stop or ordinary stop) using
an empirical approach.
• Third, the distances travelled are estimated based on a typology of logistics
practices and the geographical configuration of the urban area.
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