The distribution of benefits from port investment

This paper examines the question of who gains from reduced freight rates passed on by shipowners who derive benefit from port investment.     

Use of public information for road-capacity reductions: a study of mediating strategies during tunnel rehabilitations in Oslo

Transportation - In this paper, two public information campaigns were analysed. These were related to capacity reductions, caused by maintenance work, in two main road tunnels—at Smestad and...     

The influence of panel effects and inertia on travel cost elasticities for car use and public transport

Transportation - Studies on the impact of changes in travel costs on car and public transport use are typically based on cross-sectional travel survey data or time series analysis and do not...     

Welfare effects of road pricing and traffic information under alternative ownership regimes

This paper models strategic interactions between a road supplier, a provider of traffic information, and road users, with stochastic travel times. Using a game-theoretical analysis of suppliers’ pricing strategies, we assess the social welfare effects of traffic information under various ownership regimes. The results show that the distortive welfare effect of monopolistic information pricing appears relatively small. Collusion of the road operator and information provider yields higher social welfare than independent pricing by two firms. The intuition behind this result resembles that behind the welfare effects of double marginalization, but is not exactly the same, as traffic information is not strictly complementary to road use.     

Numerical investigation on the dynamic characteristics of an automotive A/C hose

The objective of this study is to investigate the dynamic deformation characteristics of an automotive A/C hose assembly using the finite element method and experimentation. The finite element analysis consisted of two analyses, specifically, a modal and a transient analysis. The dynamic modal analysis was conducted to assess the dynamic characteristics of the A/C hose structure, and the dynamic transient analysis was performed to investigate the dynamic stresses of an automotive A/C hose by dynamic loading with particular emphasis on the reinforced braid. Furthermore, the analyses results are expected to provide useful reference data in the design optimization of the hose layout related to the constrained design space. Modal testing was undertaken to verify the FE model. The FE result was in good agreement with the experimental results. The modal analysis result showed that the bending and swing modes of the hose occurred in the first six natural frequencies. The dynamic transient result showed that the maximum stress in the hose components occurred in the reinforced braid layers, which are particularly damage-prone.     

Integrating geographic information systems into transit ridership forecast models

Researchers have produced sophisticated modal split and transit demand models, including forecasts that are sensitive to the level of service. However, little effort has been made to integrate these models into corridor studies and route alignment analyses since (a) re-routing is itself an extremely complex modeling task, and (b) the results of the demand models are presented in tabular form with no facility to visualize spatial patterns and relationships that, if recognized, would aid in the routing tasks. GIS tools can be used, together with the demand models, to identify both clusters of city blocks that house families with certain socioeconomic characteristics and potential trip destinations conducive to transit use. In other words, GIS tools can be used to better measure some of the factors that are needed by transit demand models. The results of these models can be displayed graphically, enabling analysts to target places needing improved service, evaluate route re-alignment alternatives, and operate more efficient and effective bus lines. This paper examines how a particular class of model used by transit agencies for estimating ridership can be integrated with GIS tools in order to facilitate such analyses. It also explores the effects of visualization of routes, demographics, and employment data on the process of designing route alignments with better targeting of high transit ridership areas. This paper is part of a research project sponsored by the Region One University Transportation Center, at MIT.     

Behaviour of the Normal Contact Force Under Multiple Wheel/Rail Interaction

The wheel/rail contact forces are calculated in the frequency domain using a track model with multiple wheels on the rail. The effects of the wave reflections between the wheels on the contact force are studied. Different pad stiffnesses are used in the calculations to investigate the influence on the contact force. It is shown that the contact force can have up to four main peaks in the frequency region 550-1200?Hz due to the wave reflections between the wheels, so that the wavelengths of short pitch corrugation can be expected to be associated with multiple frequencies. As a conclusion, it is recommended that in a model for predicting short pitch corrugation the effects of multiple wheel/rail interactions need to be included.     

A summary of the formation and seasonal progression of the Northeast Water Polynya

A summary of the seasonal development of the Northeast Water Polynya ice cover characteristics is presented. This is based primarily on satellite remote sensing observations, with some in situ measurements, including both new and published data.     

From piggyback to double-stack intermodalism

Intermodal transportation has been growing at a fast pace thanks to the development of double-stack trains, deregulation of US domestic transportation and intensified competition in the liner trade. Its growth has been supported by import traffic in the recent past but will have to rely much more on domestic cargo in the future. Effective marketing rather than hardware development will pose the primary challenge to intermodal transportation. To meet this challenge, rail, highway and ocean carriers will have to rethink their business philosophy and realign themselves for more efficient provision of intermodal services. The traditional division between international and domestic intermodal operation has become obsolete.