Gernot Liedtke

Impacts of Urban Logistics Measures on Multiple Actors and Decision Layers: Case Study

An approach for a multiagent model on urban commodity transport is presented. Special attention is paid to the relationship between shippers and carriers. Shippers choose lot sizes, and they commission one or several carriers. Carriers consolidate shipments in hub-and-spoke-transport networks or in en route pickup and delivery tours. Shippers and carriers interact in a transport market where carriers submit offers to the shippers. The effects of urban transport policy measures are transmitted to the ultimate decision makers in transport—the shippers—via prices. Transport tariffs are calculated on the basis of full cost using an activity-based costing schema. The model assesses the effects of a cordon toll in the Tokyo metropolitan area to shippers and carriers. In particular, it analyzes the impacts on market shares and the spatiotemporal structure of truck flows.

A conceptual proposal for an expert system to analyze smart policy options for urban CEP transports

Courier, express and parcel (CEP) transports have been growing significantly. CEP is one of the biggest segments in urban freight transport. It does not only contribute to the wealth of our cities, but also comes with negative impacts such as noise, congestion and pollution. Transport policy has developed measures to reduce these negative impacts. This paper proposes a conceptual framework to analyze smart policy options. It focuses on the derivation of CEP demand and supply.

Simulation-based Assessment of Cargo Bicycle and Pick-up Point in Urban Parcel Delivery

Abstract Urban parcel delivery has become the bottleneck of E-commerce. This bottleneck is not only created by the cost of delivering parcels, but also caused by the difficulty to realize faster and more flexible but precise deliveries in an unreliable and dynamic environment. The questions arise how to relieve the pressure caused by last mile delivery from the logistics companies, and from the traffic and environmental system. This article intends to answer the question, whether a shift to (i) a bicycle-based last mile distribution or (ii) the use of pickup-points is desirable from a societal point of view. We study these measures exemplarily for the case of Berlin. Simulation models represent the spatial structure of the city (network, spatial disparities) and the temporal characteristics of traffic flows. Two measures are addressed by two simulation case studies: delivering on the last mile by cargo bicycles and rerouting of parcels to pick-up points. We show that the last mile by cargo bicycles is suited to reduce the delivery cost; it also has positive impact on the environment. In the case of the pickup points, the additional trips of private customers to these points largely exhaust the benefits from the saved mileage of the delivery vehicles. The present research also critically examines that the micro simulation models are possible to assess the net effects of such innovations once they are applied on a large scale.

Freight Transport Demand Modelling

Due to the structural heterogeneity of freight transport and its long-term subordinate consideration, there have been low research activities in this field as well as low motivations to integrate this segment into transport demand models for decades. There is also no generally valid framework for freight transport modelling in comparison to passenger transport modelling. Without a common framework, it is difficult to exchange ideas between scientists and to enable an efficient communication and solid agreements between a client and a contractor of a transport modelling service. This contribution presents a typological order of characteristics of freight transport demand models which covers their internal structures and employed methods. In addition, a systematic overview of selected international freight transport demand models is given.

Globaler Verkehr II: Entwicklung der globalen Güterverkehre und verkehrspolitische Implikationen

In den vergangenen Jahrzehnten konnte im Bereich der globalen Guterverkehre ein starkes Wachstum verzeichnet werden. Inzwischen beeinflussen die globalen Guterstrome signifikant die Verkehrsstrome in Deutschland. Zudem haben Anderungen im Ausenhandel direkte Auswirkungen auch auf die nationalen Nachschubketten. In Folge der globalen Finanzkrise 2008 gab es drastische Einbruche und Verwerfungen im internationalen Transportsektor, die inzwischen in eine mehrjahrige Stagnation gemundet sind. Daher stellt sich die Frage, ob die starke Wachstumsdynamik, wie sie in der Vergangenheit beobachtet werden konnte, auch weiterhin fur die Zukunft zu erwarten ist, oder ob sich mittel- bis langfristig auch Abschwachungen begleitet von strukturellen Veranderungen ergeben konnten. Mit Hilfe einer theoriegeleiteten Diskussion der Treiber des internationalen Guterverkehrs und vereinfachten Zeitreihenanalysen formuliert der vorliegende Beitrag eine mittelfristige Wachstumsprognose. Auf Basis dieser Prognose werden Implikationen und Ziele fur eine zukunftsorientiere Verkehrspolitik abgeleitet.