Determining bicycle infrastructure preferences – A case study of Dublin

This paper examines infrastructure preferences for cyclists and determines the factors that have the greatest influence on the correlation between the level of cycling confidence and preferred types of infrastructure and route characteristics. A stated preference survey is used to gauge preferences for a range of infrastructure types and route characteristics in Dublin. Facilities that were segregated from traffic are the preferred form of cycling infrastructure, regardless of cycling confidence. Routes through residential streets and parks are the second choice, where no specific infrastructure is provided with the exception of improvements in way-finding.     

On the perceived justice of urban road pricing: An empirical study in Lyon

Various methods of restricting automobile traffic, by price (tolls) or by quantity (odd/even license plates or limited days of traffic), are tested in a survey (N ～ 400) about attitudes toward traffic restrictions in Lyon, France. Ordered probit models with random-effects panel allow us to estimate the survey respondents’ perceptions of these methods, as well as the roles of individual socio-demographic characteristics in the formation of these perceptions. Both the restriction of automobile traffic and its regulation by congestion (waiting in line) are widely considered unjust by the respondents, regardless of whether they work and whether they are drivers or non-drivers. Their attitudes towards tolls justified by the pollution caused by automobile traffic are less negative. As regards compensation, in addition to emergency vehicles and those that transport people with limited mobility, respondents believe car-pooling ought to benefit of a toll exemption. The support for a reduced rate for low-income users shows a concern for justice to which it will be necessary to respond. The respondents’ socio-professional status, level of education, car use or non-use, and residence inside or outside of the toll zone clearly play a role in their perceptions of these methods of regulation and compensation.     

Impact of different shopping stages on shopping-related travel behaviour: analyses of the Netherlands Mobility Panel data

From the moment e-shopping emerged, there have been speculations about its impact on personal mobility. A fair amount of research has already been carried out on Internet shopping itself as well as on its consequences for mobility. Most studies focus on the overall impact of online shopping on personal mobility. However, little is known about how personal shopping mobility can be characterised when differentiating its constituent stages, being browsing/orienting, comparing, selecting and purchasing products, and how this is affected by e-shopping. This will be the main topic of this paper. We will investigate this using recently collected data from the Netherlands Mobility Panel [in Dutch: MobiliteitsPanel Nederland (MPN)]. It is the unique combination of reported shopping trips in the three-day travel diary, the large amount of personal and household characteristics combined with the detailed information from the e-shopping questionnaire that enables us to perform this research. Using factor analysis, we explore the underlying factors related to the browsing and selection behaviour prior to the purchase of a product. Using these factors as a starting point, we apply cluster analysis resulting in three homogeneous groups of shoppers with different pre-purchase shopping behaviour. The groups differ clearly with respect to personal and household characteristics, in the frequency with which they buy and sell products online and in their perception of (dis-)advantages of online shopping. Once relevant groups have been distinguished and characterised, differences in shopping-related mobility between them are studied in two different ways. Firstly, we analyse statements from shoppers on how their shopping-related mobility has changed. Secondly, we analyse shopping trips reported in the three-day travel diary. Only one group, which consists of shoppers that rely on the Internet to search for product information, compare prices and get new product ideas, states that their shopping-related travel behaviour has changed since they started shopping online. Approximately 50% of all shoppers experienced no difference in their shopping mobility. The analysis of actual shopping mobility using the travel diary data showed only minor differences in shopping-related travel behaviour between the identified groups. Finally, we fit a multi-variate linear regression model of shopping trip distance to determine if (e)-shopping characteristics influence trip distances. The frequency with which people shop online as well as some stated changes in shopping-related travel behaviour (shopping in a similar manner and shopping longer) turn out to influence non-grocery shopping trip distance. No significant influence could be found of shopping cluster membership on shopping trip distances.

     

A fractional perspective to the modelling of Lisbon’s public transportation network

Transportation - Urban growth originates multiscale spatial patterns, such as those of transportation networks. Here, the public transportation network (PTN) of the city of Lisbon is analysed from...     

Contributions to maritime economics—Zenon S. Zannetos,the theory of oil tankship rates

This paper discusses the importance of Zannetos’ 1966 book for the development of maritime economic thought. The main contributions of the book are recounted, and the empirical work in the book is reviewed.

The analysis of the present paper is a citation research on the maritime economics literature that refers to the book. Of the 42 papers in the set, about one-third refers to the book in general. A total of 35 papers refer to one or more elements of the book, with an equal number of references to: (1) the term structure of freight rates; (2) the empirical findings on the form of the supply curve; and (3) on the verification of his results.

The general conclusion of the citation analysis is that, apparently, a number of elements of his work are still very valid for current maritime economics thinking, while maritime economists have disregarded several other elements. The latter seems unjustified for some of the business structure observations that are made in the book, such as the notion that the ship is the firm, and the elasticity of expectations. The former observation is the basis for virtually all empirical work in maritime economics that is based on individual contract data (all freight rate analysis is of this nature), and the second is the basis for the analysis of investment behaviour in shipping, investigations of cyclicality and so on.

Zannetos can definitely be seen as the initiator of the important field of term structure analysis in maritime economics. In addition to this, there are several topics in the 1966 book that are as yet unexplored, and deserve empirical scrutiny.     

Manoeuvring and hotelling external costs: enough for alternative energy sources?

Local air pollution is the most relevant externality of maritime transport, and its effects are more acute in urban areas as a result of manoeuvring, hotelling and load/unload activities at ports. This article is intended to assess ships’ local air pollution impact in generally densely populated harbour areas to decide whether alternative power supply measures are feasible. First, an optimized infrastructure investment model is developed to ease implementation and maximize the efficiency of alternative power supply projects. Once target harbours and traffic (ship types) within a national port network have been chosen, a vessel traffic analysis (ship type, tonnage, manoeuvring, and hotelling times) is carried out to quantify and evaluate annual polluting emissions (PM_2,5, SO₂, NOx, and VOCs) and their externalities. Finally, the assessment model is applied and results of the Spanish port network case study are discussed. The results obtained are significant and bring the possibility of further controlling the ship’s environmental performance at berth.     

The Gulf Stream, rings and North Atlantic eddy structures from remote sensing (Altimeter and SeaWiFS)

Seasonal SeaWiFS chlorophyll a concentrations cycles and annual changes of altimeter Sea Level Anomaly are derived for the subtropical North Atlantic near  35°N and along a Gulf Stream axis. Spatial structure of SeaWiFS, is defined in terms of deviations from a local seasonal cycle and examined in relation to altimeter eddy structure. In the subtropical region near 35°N, SeaWiFS structure is evident during the spring bloom period with a scale of  430 km, or about twice the eddy scale. A Gulf Stream axis has been selected as a region where the Sea Level Anomaly variance is a maximum. Eddy propagation speeds and scales are examined. Cold-core (cyclonic) rings correspond to areas of high SeaWiFS chlorophyll a. Warm-core (anticyclonic) rings relate to areas of low chlorophyll concentration. Both SeaWiFS structure and eddy structure have a spatial scale of  450 km or twice the ring scale along the Gulf Stream axis. SeaWiFS chlorophyll anomalies and Altimeter Sea Level Anomaly structure have an overall negative correlation coefficient of r = − 0.34. Swirl currents between eddies redistribute surface chlorophyll concentrations and can spatially bias maximum and minimum concentration levels off eddy centre.     

Sensitivity of the wheel–rail contact interactions and Dang Van Fatigue Index in the rail with respect to irregularities of the track geometry

This paper investigates the effects of the track geometry irregularities on the wheel–rail dynamic interactions and the rail fatigue initiation through the application of the Dang Van criterion, that supposes an elastic shakedown of the structure. The irregularities are modelled, using experimental data, as a stochastic field which is representative of the considered railway network. The tracks thus generated are introduced as the input of a railway dynamics software to characterise the stochastic contact patch and the parameters on which it depends: contact forces and wheelset–rail relative position. A variance-based global sensitivity analysis is performed on quantities of interest representative of the dynamic behaviour of the system, with respect to the stochastic geometry irregularities and for different curve radius classes and operating conditions. The estimation of the internal stresses and the fatigue index being more time-consuming than the dynamical simulations, the sensitivity analysis is performed through a metamodel, whose input parameters are the wheel–rail relative position and velocity. The coefficient of variation of the number of fatigue cycles, when the simulations are performed with random geometry irregularities, varies between 0.13 and 0.28. In a large radius curve, the most influent irregularity is the horizontal curvature, while, in a tight curve, the gauge becomes more important.     

Do maritime passengers’ subsidies in Europe affect prices?

Some European governments subsidize their residents when they travel at sea. This paper seeks to analyze the impact on prices of maritime passengers’ subsidies in Europe. Following a review of the scarce academic literature on this topic and the subsidy scheme in Europe, a sample of firms’ prices and other characteristics of 40 European routes for 2016 are analyzed. Both an estimation of a price equation and a matching approach are applied and reach the same conclusion: prices per kilometer are around 40 per cent higher on those subsidized routes due to subsidies. This outcome reduces the potential subsidy gain to consumers.