Foliated Transportation Networks - Evaluating feasibility and potential
Doktorsavhandling, 2012

Neither the critical role that transportation plays for economic activities nor its negative external effects can be denied. At the same time, the resources required to sustain and develop the transportation system to an adequate degree and at the required pace are limited. The problem that these properties result in is that the inputs of the system are finite and scarce and the external effects of it negative, but the output is too critical to do without. The most obvious path to a solution is, therefore, trying to increase output obtained from the same or a lesser amount of input. In light of this, the attempt to utilize the existing overcapacity, whatever its extent may be, and improving the operational efficiency with sustained or improved effectiveness, stands out as one of the most viable approaches. In this thesis the concept of Foliated Transportation Networks (FTN) is evaluated with regard to feasibility of its implementation and its potential impact on the performance of the transportation network. The main objective of the concept of FTN is achieving performance improvements by foliating two different network structures, i.e., direct shipment and hub and spoke, in order to minimize the underutilized units in the network and thereby achieving performance improvements. The studies show that FTN is feasible to implement in existing networks with limited requirements for additional investments in new technologies. Even though new technological platforms and innovations would be beneficial for the implementation of FTN, a majority of its identified potential can be accessed using existing technologies and rule-of-thumb control. The performance improvement potential that is identified and measured in number of units, traffic work and load factor is substantial. In addition, partial implementation is possible and about 80% of the potential could be realized when about 20% of the system is available for foliated control. The identified potential has proved to be robust following numerous sensitivity analyses.

hybrid transportation systems

transportation network modeling

intelligent transportation systems.

transportation planning and control

transportation network simulation

transportation network optimization

Transportation networks

transportation network performance

mixed model transportation

transportation network efficiency

Vasa A
Opponent: Professor Kevin Cullinane

Författare

Joakim Kalantari

Chalmers, Teknikens ekonomi och organisation, Logistik och transport

Avhandlingen unvärderar möjligheten och effekten av att "överlagra" två olika typer av transportnätverk inom ett och samma system. Praktiskt innebär detta inga förändringar i det fysiska systemet utan endast hur godset styrs. I avhandlingen har man genom en empiriskt grundat simuleringsmodell överlagrat ett navnätverk över ett direktleverans nätverk. Resultaten indikerar besparingar i resursbehov av storleksordningen 10% samt möjligheter att implementera ett överlagrat transportnätverk i befintliga system utan större behov för nyinvesteringar och att delimplementering är både möjligt och önskvärd då ca 80% av identifierad potential är uppnålig redan vid 20% penetration.

The Merriam-Webster dictionary online defines “foliated” as: “composed of or separable into layers.” The phenomenon of foliation refers to the act of combining two or more complementary systems into one that will in its performance surpass that which is possible to achieve with any of its constituting parts when used in isolation. In this thesis the foliation of a hub and spoke network on a direct shipment has been studied. It is should be noted that this action in itself does not necessitated the physical altering of the original network rather only how goods and resources are controlled though the network. The studies are primarily based on experiments run in empirically grounded simulation model of the network. The results of the experiments indicate that an efficiency improvement of roughly 10% is possible to achieve. It is further evident that it would be possible to implement FTN in existing networks without extensive new investments. Finally, it is found that partial implementation is not only possible but can in many cases be preferable as about 80% of the identified potential is achievable when only 20% penetration is reached.

Ämneskategorier

Annan maskinteknik

Transportteknik och logistik

Drivkrafter

Hållbar utveckling

Innovation och entreprenörskap

Styrkeområden

Transport

ISBN

978-91-7385-769-7

Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie

Vasa A

Opponent: Professor Kevin Cullinane