Search results for "planning."
showing 10 items of 3916 documents
Contributions to Branch-and-Price-and-Cut Algorithms for Routing Problems
2019
This article deals with new exact branch-and-price-and-cut algorithms for the solution of routing problems. Specialized methods for the pickup-and-delivery problem (PDP), the truck-and-trailer routing problem (TTRP), the periodic vehicle routing problem (PVRP) and a service network design and hub location problem (SNDHLP) are presented. We develop a new technique for the acceleration of bidirectional labeling algorithms by a dynamic choice of the merge point. Moreover, for variants of the PDP, the bidirectional labeling can be effectively applied for the first time. In the TTRP, we model the extension to a 2 days planning horizon and the consideration of a quantity-dependent transfer time. …
‘Tool port’ to ‘landlord port’: a game theory approach to analyse gains from governance model transformation
2018
This study investigates potential port users’ surplus and terminal operators’ profits due to transforming port governance from the ‘tool port’ model to the ‘landlord port’ model. Although the landl...
Operational and financial performance of Italian airport companies: A dynamic graphical model
2016
Abstract This paper provides evidence on the relationship within a set of financial and operational indicators for Italian airports over 2008–2014. The limited sample size of national and regional airports suggests to apply the penalised RCON ( V , E ) model, which falls within the class of Gaussian graphical models. It provides both estimate and easy way to visualise conditional independence structures of the variables. Moreover, it is particularly suitable for handling longitudinal data where small number of units and huge number of variables have been collected. Findings highlight that a qualified concept of size matters in determining good financial performance. Specifically, increasing…
Les effets de la livraison à domicile sur l'accès aux produits alimentaires: le cas des grandes surfaces alimentaires et des cybermarchés de l'aire u…
2012
International audience; L’accessibilité des populations aux Grandes Surfaces Alimentaires (1) (GSA) est différenciée selon les espaces. Alors qu’au cœur des villes, les urbains peuvent accéder à pied à une offre diversifiée, les périurbains et les ruraux doivent parcourir plusieurs kilomètres en voiture pour accéder au supermarché le plus proche (Motte-Baumvol, 2008). Si une très grande majorité de périurbains n’éprouvent pas de difficultés, certains y font face plus difficilement tels que les ménages sans voiture, les personnes âgées ou les familles avec des enfants en bas âge. Pour ces ménages, la livraison à domicile, notamment à partir de la vente en ligne, peut constituer un moyen d’am…
The emissions reduction potential of substituting short-haul flights with non-high-speed rail (NHSR): The case of Finland
2021
Abstract Replacing short-haul flights with high-speed rail (HSR) has been widely discussed as one solution to mitigate the climate change impacts of aviation. However, although HSR can provide travel times similar to those provided by short-haul flights, and at lower emission levels, it also requires considerable investments in time and infrastructure to build. Instead, this study considers the feasibility of replacing short-haul flights with existing non-high-speed rail (NHSR). Our study is based in Finland, a country that has an extensive route network of short-haul flights but does not possess any HSR. We compared all 16 city pairs for which short-haul flights are offered with existing N…
Dimensions fractales et réalités périurbaines. L'exemple du Sud de Bruxelles
2004
This exploratory paper aims at showing how the fractal dimension can be used to characterise the spatial structure of built-up areas within the periurban fringe. The southern periphery of Brussels is considered here. Two estimation techniques (correlation and dilation) are applied to surface areas, and one (correlation after dilation) to the borders of built-up areas. They are applied to windows of fixed size. Fractal dimensions are then compared with traditional socio-economic and morphological indicators. The results are interpreted in the context of urban sprawl and polycentric development of the peripheries. These analyses confirm the usefulness of the fractal approach for describing bu…
Relative Reachability Analysis as a Tool for Urban Mobility Planning
2019
There is a plethora of user-oriented route planning applications and systems that enable the computation of the fastest journey between two locations using different transportation modes, e.g., car, public transport, walking, bicycle. While useful for individuals, they are of limited interest to a class of users that may be interested in a more global and comparative view of transportation systems in general. In this context, we adopt the view of an urban planner. Urban planners may be interested in queries such as "if a new transit stop was to be introduced in a given location, would that bring the travel time to a given point-of-interest (POI) or area-of-interest (AOI) by bus closer to th…
Port expansion and negative externalities: a willingness to accept approach
2015
Port expansion has been seen as the origin of negative externalities, affecting local residents’ well-being and contributing to the poor public image of ports. In this study, the contingent valuation method is used to estimate the costs borne by local residents as a consequence of the negative externalities derived from the growth of the Port of Valencia (Spain) in the last 30 years. As transport project appraisal has become more complex, this technique complements existing methodologies in this field, such as the social cost benefit analysis and the multicriteria analysis. Given the perceived property rights of families that have been living close to the port for a long time, a willingness…
The potential impact of Brexit on Ireland's demand for shipping services to continental Europe
2018
Abstract Ireland, as an island nation, has historically relied on the UK landbridge to export and import its goods to and from Europe. This provides a fast, reliable and secure service along the UK landbridge route relative to the more economical and less frequent direct continental route. However, the relative competitiveness of maritime services along both routes may be significantly influenced by the UK exit from the European Union or Brexit. This paper aims to understand the potential impact of Brexit on maritime freight transport demand from Ireland to continental Europe for export trade shipments. Based on data collected from an efficient stated preference (SP) experiment, discrete ch…
Measuring foreland container port connectivity disaggregated by destination markets: An index for Short Sea Shipping services in Spanish ports
2020
Abstract The present research aims to develop a Foreland Port Connectivity Index (FPCI) including both qualitative and quantitative variables related to the characteristics of the maritime services provided. To that end, the FPCI incorporates two discount factors—the number of shipping services and destination countries—as penalties to correct for the quality of a port connection. After defining the FPCI, the index is applied to Spanish ports to study their connectivity in terms of container Short Sea Shipping (SSS) services. Although the connectivity of SSS traffic has not been widely studied, it is an interesting case study as small ports play a more relevant role in facilitating access t…