Search results for " transportation"
showing 10 items of 511 documents
Optimal transport maps on Alexandrov spaces revisited
2018
We give an alternative proof for the fact that in $n$-dimensional Alexandrov spaces with curvature bounded below there exists a unique optimal transport plan from any purely $(n-1)$-unrectifiable starting measure, and that this plan is induced by an optimal map.
Slopes of Kantorovich potentials and existence of optimal transport maps in metric measure spaces
2014
We study optimal transportation with the quadratic cost function in geodesic metric spaces satisfying suitable non-branching assumptions. We introduce and study the notions of slope along curves and along geodesics and we apply the latter to prove suitable generalizations of Brenier's theorem of existence of optimal maps.
Mass transportation on sub-Riemannian structures of rank two in dimension four
2017
International audience; This paper is concerned with the study of the Monge optimal transport problem in sub-Riemannian manifolds where the cost is given by the square of the sub-Riemannian distance. Our aim is to extend previous results on existence and uniqueness of optimal transport maps to cases of sub-Riemannian structures which admit many singular minimizing geodesics. We treat here the case of sub-Riemannian structures of rank two in dimension four.
The Heterogeneous Fleet Vehicle Routing Problem with Draft Limits
2023
Over the past two decades, international maritime transport has been characterized by the advent of ever larger ships. This phenomenon is known as naval gigantism. If, on the one hand, naval gigantism allows to reduce transport costs by exploiting the economies of scale achievable by large ships, on the other hand, it implies a series of operational issues. Indeed, due to their large draft, such giant vessels are not allowed to enter small ports when fully or near-fully loaded, and in some cases, they cannot enter such small ports at all. In fact, their draft can strongly vary depending on the load on board. This implies restrictions for vessels in accessing ports, which impact not only at …
Mesure du transport narratif dans le contexte d’une expérience de consommation transmédia
2018
This research offers a French narrative transportation scale measuring the experience of transmedia devices in the arts and cultural field. First, based on a literature review of the definition and measure of narrative transportation, a new scale is presented and defended. Second, a qualitative study is conducted. The dimensions of narrative transportation are confirmed and items are generated to measure it. Results from factorial analysis leading to a reliable and valid scale of narrative transportation lived by the cultural consumer through the use of a transmedia device are presented.
Cycling for Home-to-School Travel in Palermo: A Method for Assessing the Optimal Allocation of New Cycling Infrastructure
2019
In order to reduce the number of cars on the road, one of the most incisive actions is to encourage cycling, e.g. through the introduction of bike-sharing systems. In particular, the activation of special bike-sharing programs for school students could lead students to choose this mode of transport to make their own home-school travel. The success of such initiatives is primarily linked to the presence of a continuous and functional cycle network, which can create safe routes to school. It is, therefore, necessary a cycle network design model that allows determining the optimal allocation of new cycle paths, maximizing the number of users and considering technical and economic constraints. …
On deterministic solutions for multi-marginal optimal transport with Coulomb cost
2022
In this paper we study the three-marginal optimal mass transportation problem for the Coulomb cost on the plane $\R^2$. The key question is the optimality of the so-called Seidl map, first disproved by Colombo and Stra. We generalize the partial positive result obtained by Colombo and Stra and give a necessary and sufficient condition for the radial Coulomb cost to coincide with a much simpler cost that corresponds to the situation where all three particles are aligned. Moreover, we produce an infinite class of regular counterexamples to the optimality of this family of maps.
A GIS-Based Methodology for Evaluating the Increase in Multimodal Transport between Bicycle and Rail Transport Systems. A Case Study in Palermo
2021
Background: In a world where every municipality is pursuing the goals of more sustainable mobility, bicycles play a fundamental role in getting rid of private cars and travelling by an eco-friendly mode of transport. Additionally, private and shared bikes can be used as a feeder transit system, solving the problem of the first- and last-mile trips. Thanks to GIS (Geographic Information System) software, it is possible to evaluate the effectiveness of such a sustainable means of transport in future users’ modal choice. Methods: Running an accessibility analysis of cycling and rail transport services, the potential mobility demand attracted by these services and the possible multimodality bet…
The role of the transportation phase for a green management of municipal solid waste
2017
Municipal solid waste management (MSWM) constitutes a high challenging issue to cope with to move towards sustainability of the urban policies. Despite new standards call for recycling and reusing materials contained in the city waste, several municipalities still use extensive landfills. Other than the environmental pressure exerted by these plants, the waste transportation from the recovery points of towns to landfills needs consideration to correctly assess the whole burden of the waste management. In this paper, the Ecological Footprint indicator is applied to the MSWM of the town of Palermo (Sicily). Results show that the effects produced by the involved transportation vehicles, both i…
What?s new in intelligent transportation systems?: An overview of European projects and initiatives
2013
This article is a taxonomy of recent intelligent transportation systems (ITS) initiatives/projects in Europe, and it covers nearly all of the main segments of the transportation sector. The purpose is to appraise the milestones that have been reached so far in the area of ITS. Furthermore, this article will help in identifying directions for future research. By highlighting the potential advantages users get through deployed ITS solutions, this article stimulates the interest of users and relevant stakeholders in the uptake of this technology. Finally, it will also serve as a useful resource for those agents of the scientific community who are interested in taking part in the European Commi…