Abstract

International audience; The development of renewable marine energies has its origin in the United Nations' Framework Convention on Climate Change, adopted on 9 May 1992, and in the additional protocol, adopted in 1997 in Kyoto. Although, for many years, the French legal system did not consider the specificities of ocean renewable energies, the French government now seems to have become aware of the importance of establishing an adapted legal framework. The boom of marine renewable energies is the result of proactive policies from a French nation that seeks to meet its international and European commitments. The French policy makes use of legal instruments that ensure programming and planning. The economic activities in the field of marine renewable energies make up a market to which access is regulated. This requires administrative procedures which are as varied as they are complex. © ISTE Ltd 2015. All rights reserved.

Abstract

This study presents a real-data approach that aims at optimizing the location of urban loading-unloading (L/U) spaces. The originality of this paper is twofold: first, it proposes a data collection methodology in order to integrate real and up-to-date information regarding cartography, L/U parking demand and existing L/U spaces. Second, an optimization model is developed in order to determine the location of new L/U spaces by taking into account real distances, influence radius and physical constraints. Such optimization model can be used to evaluate the relevance of the existing L/U spaces and/or to determine the optimal location of new ones. For this we propose to combine the use of OpenStreetMap, Google Maps APIs, and Open Data portals. This paper provides a framework composed by 3 models, namely: data collection, demand generation and location optimization. The proposed approach is applied to the city of Paris in order to illustrate different case studies and to assess the effectiveness of the framework.

Abstract

International audience; Because it deals with sustainably supplying cities and reducing congestion and pollution related to goods transport in urban areas, city logistics is an important field in transportation sciences. These logistics systems need to be sustainable and reliable to ensure the continued flow of goods.Logistics and Transport Modeling in Urban Goods Movement is a pivotal reference source that provides vital research on the main approaches and techniques used in urban goods transport modelling while addressing planning and management issues. Highlighting topics such as urban logistics, vehicle routing, and greenhouse emissions, this book is ideally designed for civil/transport engineers, planners, transport economists, geographers, computer scientists, practitioners, professionals, researchers, and students seeking current research on urban goods modelling.

Abstract

The 9th International Conference on City Logistics, Tenerife, Espagne, 17-/06/2015 - 19/06/2015; Electric vehicle is a solution to reduce pollutant emissions from road urban freight. This paper assesses the potential CO2 reduction by transferring urban freight from diesel to electric vehicles while simultaneously looking at the two main technical constraints: electric vehicle range and the impact on congestion linked to change diesel heavy duty vehicles (with a load up to 25 tons) to much smaller electric vehicles. The data used has been computed from a survey (ECHO) that describes in details a very large sample of French shipments. Two scenarios were set up, which differ mainly by the type of available electric vehicle: In scenario E1, the electric vehicle has a payload of 2 tons, versus 6 tons in scenario E2. The vehicle range is not very binding for urban deliveries in our scenario, except in the Paris Urban area. The CO2 reduction is nearly the same in the two scenarios, but the congestion is much higher in scenario E1, showing that the payload is an important issue for the generalisation of electric vehicles in urban freight. Document type: Conference object

Abstract

Abstract. In developing countries, metropolitan cities, due to their economic activities, attract an increasing amount of commuters on a daily basis. This has led to major freeways and roads experiencing high levels of congestion and consequently high pollution levels. In 2020, due to a global pandemic of an outbreak of Corona Virus (COVID-19), the national government declared a national shutdown with only essential traffic being allowed to operate. Given the scenario of the national lock-down this allows for the statistical analysis of the impact of essential traffic on the overall transportation system. Consequently the aim of the paper was to assess the congestion and CO2 emission impact of essential traffic for the City of Johannesburg. Using an exploratory approach, we monitored and collected traffic congestion data from the Tomtom traffic index for the metropolitan city of Johannesburg, South Africa. We develop a relationship between congestion and pollution to visualise the daily variations in pollution and congestion levels. We demonstrate this by comparing variations in congestion levels in two epochs, viz the period without movement restrictions and the period whereby movement is restricted. The results reveal essential traffic on the congestion index to be below 22 percent for both weekends and weekdays. A scenario common only during weekends in 2019. Whilst for the emission index, CO2 levels are approximately less than 45 percent throughout the week. The paper concludes the investment into mining and analysing traffic data has a significantly role for future mobility planning in both the developed and developing world and, more generally, improving the quality of commuting trips in the city. Document type: Article

Abstract

International audience; Innovations in the airline industry can have a significant impact on the behavior of air transport stakeholders: airline companies, airports and passengers. In this paper, we consider the introduction of a double-deck plane, the A-380, which is currently the largest aircraft available. Due to its size, it is able to carry at once approximately twice as many passengers as any other medium-sized aircraft. When associated with a reduction in flight frequencies , the operation of such aircraft is expected to lower the environmental impact. However, flight frequency depends on factors others than the aircraft size, such as airport fees, demand and strategic decisions of companies to maximize their profits under competition. Using a monthly panel data set on airlines' supply over 10 years, on 118 routes, we test if the use of the A-380 impacts airlines' flight frequency at a route-level. Results suggest that heavy use of the A-380 leads airlines to reduce their own flight frequency. We also find that when facing the introduction of the A-380 on a route, airlines will tend to react by increasing their own flight frequency.

Abstract

International audience; Rendering the supply chain more carbon-friendly is an innovative idea progressively adopted by industry. Transport accounts for one-fifth of the carbon emissions that are generated on French territory. Among the different transport modes, road transport is the one responsible for the majority of transport emissions. Our research focuses on the CO2 emissions along the supply chain due to road freight transport. Accordingly, we conduct a greenhouse gas (GHG) emissions assessment of a transport company. The main objectives of the study are twofold: identifying the main emission sources and improving green supply chains.

Abstract

ITSC 2019, IEEE Intelligent Transportation Systems Conference, Auckland, NOUVELLE-ZELANDE, 27-/10/2019 - 30/10/2019; Ridesourcing services play a crucial role in metropolitan transportation systems and aggravate urban traffic congestion and air pollution. Ridesplitting is one possible way to reduce these adverse effects and improve transport efficiency. This paper aims to explore the potential of ridesplitting in peak hours using empirical ridesourcing data of Chengdu, China provided by DiDi Chuxing. A ridesplitting trip identification algorithm based on a shareability network is developed to quantify the potential of ridesplitting. Then, we evaluate the gap between the potential and actual scales of ridesplitting, which the literature has not yet reported. We compare the potential of ridesplitting under three different objectives. The results show that the objective of minimizing the total travel cost produces better performance than the objectives of maximizing shared trips and time savings. Under the objective of maximizing cost savings, the percentage of potential cost savings is 18.47% with an average delay of 4.76 minutes, whereas the actual percentage is 1.22% with an average delay of 9.86 minutes. The potential percentage of shared trips is 90.69%, while the actual percentage is 7.85%. Furthermore, the potential time savings can reach 25.75%, while the actual time savings are 2.38% in the real world. The findings of this study can help transportation management agencies and ridesourcing companies develop sensible policies to improve ridesplitting services.

Abstract

International audience; Regulatory policies aim at reducing the negative effects of urban freight transportation, especially those related to traffic, emissions and noise. Nonetheless, stakeholders in city logistics often have divergent objectives, which lead to difficulties upon defining the best possible choices regarding regulation. This paper presents a multi-agent and discrete-event based simulation of urban deliveries that aims at evaluating the impacts of regulatory policies. Restrictions regarding vehicle weights and time windows are considered in order to measure the impacts on deliveries based on total distances, number of vehicles, loading rates and air pollutant emissions. The simulation framework is applied to the delivery services for restaurants, in which 4 scenarios of regulation are evaluated in the city of Paris. One originality of the proposed approach is to use real data for the instantiation of agents and the GIS in the simulation.