Search results for "Transportation"
showing 10 items of 860 documents
Solving congestion in cities : policies and contradictions
2009
International audience; Most cities in the world are now facing traffic gridlock. Local governements and transportation authorities are trying to tame a phenomenon which takes in fact very different forms depending on the level of social and economic development. Is it really possible to compare freeway gridlock in Los Angeles with rickshaw gridlock in Dhaka, Bangladesh ? When French cities embrace the development of urban bicycling, Chinese cities limit the use of bicycles. Using cases of cities in different parts of world, this presentation willl try to find some common trends in urban mobility policies and examine some contradictory developments.
Rebuilding a Cluster while protecting knowledge within Low-medium-tech supplier SMEs: A Spanish and French comparison
2021
International audience; Most of SMEs are engaged in open innovation practices, but they do not benefit from open innovation or from patenting in the same way as larger firms do. At the same time SMEs, as territorialized suppliers, play a crucial role within evolving regional specialization. In this context the purpose of our study is to examine how low and medium technology supplier SMEs learn and organize themselves at a territorial level to address the challenge of IP protection in an open innovation paradigm. We used a qualitative method with a longitudinal multi-case study involving 27 companies with a historical lance to compare the territorial dynamics of knowledge protection within c…
Prediction of hydraulic and acoustic properties of open-graded mixes
2014
The use of open-graded mixes increases significantly the hydraulic permeability of pavement and contributes to reduce the noise impact in comparison to traditional pavement. Such characteristics are very appealing and would greatly increase driver's safety. However, during service life, the pores tend to be clogged by many factors among them secondary traffic compaction and filling of voids by fine materials are relevant, especially on heavy routes. In this case the noise reduction and drainage capabilities will gradually disappear, causing serious problems for road safety and maintenance. In this paper we propose a simulation approach in order to predict the drainage and acoustic behavior …
Croissance endogène et espace
1997
International audience
Forecasting Passenger Traffic for a Regional Airport
2019
Abstract The purpose of the present research is estimating the potential traffic for SIA (Sibiu International Airport, SBZ) for the year 2017. Predicting as accurate as possible the passenger traffic for a certain airport is an aspect of major importance for both the airport management and the airline companies. The theoretical quality of the forecasting models for air traffic of passengers is fundamental for obtaining the most accurate predictions. In this regard, a two-step process was used in developing the traffic forecasting model: (1) Identifying the proper regression model for traffic estimation based on the number of aircraft departures, and (2) Forecasting the number of aircraft de…
Analysis of the Structure and Dynamics of European Flight Networks
2022
We analyze structure and dynamics of flight networks of 50 airlines active in the European airspace in 2017. Our analysis shows that the concentration of the degree of nodes of different flight networks of airlines is markedly heterogeneous among airlines reflecting heterogeneity of the airline business models. We obtain an unsupervised classification of airlines by performing a hierarchical clustering that uses a correlation coefficient computed between the average occurrence profiles of 4-motifs of airline networks as similarity measure. The hierarchical tree is highly informative with respect to properties of the different airlines (for example, the number of main hubs, airline participa…
Barriers and (im)mobility in Rio de Janeiro
2016
In Rio de Janeiro, immobility or the share of people with no journeys on any given day is very high (46%). Immobility has a marked geographical dimension in what is a segregated city. But income has only limited explanatory power. The population structure, with high proportions of people who are not in the labour force and who are unemployed, accounts for the high levels of immobility in the poor districts. Although population structure effects prevail, spatial factors such as the severance effect also account for differences between districts. Indeed, Rio de Janeiro features many different types of barriers that affect immobility in several districts and for several population groups. The…
Turbo-Roundabout: Case Study of Driver Behavior and Kinematic Parameters of Light and Heavy Vehicles
2019
AbstractThis research compared kinematic and behavior parameters of light and heavy vehicles at turbo-roundabouts. This is of interest because heavy vehicles can influence turbo-roundabout function...
Have information technologies forgotten pedestrians?
2018
Worldwide, pedestrians make up close to half of all motor-vehicle related fatalities but disproportionally little of the research in Information Technologies (IT) in general and Intelligent Transportation Systems (ITS) in particular has aimed at pedestrian safety improvements. This paper analyses and compiles three different ways so that IT and ITS can be used in order to improve mobility and safety of pedestrians in urban spaces: (a) for contacting and/or being localized, (b) for guidance (leading/navigating), (c) for alerting or informing of a danger. The aim is to categorize recent experiences where ITS can improve pedestrians’ mobility and safety so that new ideas based on ITS will be d…
Using recursive Bayesian estimation for matching GPS measurements to imperfect road network data
2010
Map-matching refers to the process of projecting positioning measurements to a location on a digital road network map. It is an important element of intelligent transportation systems (ITS) focusing on driver assistance applications, on emergency and incident management, arterial and freeway management, and other applications. This paper addresses the problem of map-matching in the applications characterized by imperfect map quality and restricted computational resources - e.g. in the context of community-based ITS applications. Whereas a number of map-matching methods are available, often these methods rely on topological analysis, thereby making them sensitive to the map inaccuracies. In …