Search results for "Transport engineering"
showing 10 items of 196 documents
Environmental, functional and economic criteria for comparing “target roundabouts” with one- or two-level roundabout intersections
2015
The article describes a criterion based on functional, environmental and economic aspects for comparing conventional roundabouts with innovative one- or two-level roundabouts. We compared the performances of eight roundabout types, differing in geometric layout, number of lanes and traffic flow regulation from each other, with regard to vehicle delays and CO2, NOx, PM2.5 and PM10 pollutant emissions. Recently-designed roundabouts - target roundabouts and flyover roundabouts - have also been studied for their undoubted practical interest. By means of closed-form capacity models and CORINAIR methodology, several traffic simulations were carried out to examine a typical annual traffic demand c…
Implementation of the driver training curriculum in Spain – An analysis based on the Goals for Driver Education (GDE) framework
2014
Abstract The Goals for Driver Education (GDE) framework represents a conceptual outline of the goals to be satisfied in driver education (Hatakka et al., 2002). We aimed to analyze the implementation of the driver training curriculum in Spain, taking this framework as reference; the Spanish driving instructors was the target population from which to gather the information to be analyzed. For this purpose, we developed the DTCI (Driver Training Curriculum Implementation) scale as well as a number of questions concerning the driving instructors’ opinions about their own training as instructors, and they were included in a survey that provided information for a probabilistic sample of 676 driv…
Improving the sustainability of transportation: environmental and functional benefits of right-turn by pass lanes at roundabouts
2015
The functional performances of conventional roundabouts (single-lane and multi-lane) and innovative roundabouts (spiral, flower, C and turbo) can be improved through right-turn bypass lanes controlled by stop, yield or free-flow signs. The article presents evaluations of the emissions of air pollutants (carbon dioxide, nitrogen oxides, particle pollution (PM10 and PM2.5)), fuel consumption and construction, management, energetic and environmental costs in roundabouts without or with bypass lanes (controlled by stop, yield or free-flow). The suggested methodology has a general character and can be applied as a multi-parametric criterion for choosing road intersections, although, in the prese…
Effect of climate change on asphalt binder selection for road construction in Italy
2015
This work explores the influence of climate changes on the proper selection of asphalt binder for pavement construction purposes, according to the Performance Grade (PG) defined in the SUPERPAVE specifications. Based on temperature data at national level, it is possible to obtain thematic maps for the whole Italian territory, which is extremely useful for technicians and pavement engineers for selection of asphalt binder for road construction purposes. Furthermore, the statistical significant temperature trends’ knowledge enables deriving thematic maps which allows to include the effects of climate change in the asphalt binder design. It is argued that, due to climate change, the binders to…
Sustainable mobility: “exchange poles” between transport networks and urban structure
2012
An intermodal hub can be defined as a place where transportation networks are organized to facilitate intermodality between different modes. Intermodal hubs should intrinsically have an urban dimension and be globally designed as “plug flows”, being interfaces between transport networks and territory, being an element to create “urbanity”. Intermodal hubs focus technical, social, urban, transport, service aspects and they play a multi-modal, multi-service, multioperator role. Several studies highlight the need to “measure the interdependence” among the various aspects of urban problems, avoiding too specific methodologies. The increasing congestion in urban centres and urban parking problem…
Characterizing the "driver DNA" through CAN bus data analysis
2017
People's driving behavior is influenced by different human and environmental factors, and several attempts to characterize it have been proposed. Nowadays, the standardization of the CAN bus and the increase of the electronic components units in modern cars offer a large availability of sensors data that make possible a more reliable and direct characterization of driving styles. In this work, we propose the concept of "Driving DNA" as a way of describing the complexity of driving behavior through a set of individual and easy-to-measure quantities. These quantities are responsible for some aspects of the driver's behavior, just as -- in the metaphor -- genes are responsible for the tracts o…
Sustainable Transportation Management System for a Fleet of Electric Vehicles
2015
In the last few years, significant efforts have been devoted to developing intelligent and sustainable transportation to address pollution problems and fuel shortages. Transportation agencies in various countries, along with several standardization organizations, have proposed different types of energy sources (such as hydrogen, biodiesel, electric, and hybrid technologies) as alternatives to fossil fuel to achieve a more ecofriendly and sustainable environment. However, to achieve this goal, there are significant challenges that still need to be addressed. We present a survey on sustainable transportation systems that aim to reduce pollution and greenhouse gas emissions. We describe the ar…
Contribution to the platoon distribution analysis in steady-state traffic conditions
2014
The traffic flow analysis and the relevant vehicle distribution (“free-moving” or “platooned” vehicles) on highway facilities at uninterrupted flow has always had fundamental importance in Highway Engineering, with special reference to topics like traffic operations, car accidents, road safety and air pollution emissions. In light of this, the study suggests a calculation algorithm as a random test generator to simulate a steady state traffic flow and to provide time headways. Thanks to the outcome produced by numerical simulations, we analysed platoon distributions within traffic flows in a steady-state regime and showed the results of numerical analyses carried out by traffic random proce…
Co2 emissions of French shippers: The roles of delivery frequency and weight, mode choice, and distance
2014
In this article, the authors describe the effects of delivery frequency, mode choice, distance, and shipment weight on the CO₂ emissions of French shippers, taking advantage of a 2004 survey of French shippers (ECHO) which describes the characteristics of 3000 shippers, 10,000 shipments, and 20,000 transport chain legs. Once the energy consumption and CO₂ emissions of every shipment have been computed, they are divided by the corresponding number of ton-kilometers in order to find their carbon intensity (in grams of CO₂ per ton-kilometer). The authors then analyze the latter with respect to a number of selected shipment characteristics: shipment frequency and mode choice (planning choices),…
Carbon Intensity of French Shippers
2014
International audience; To estimate CO2 emitted by a French shipper for the transportation of its shipments, we use the French shipper survey. In this survey, we only have three shipments per shipper and carbon intensity per shipment is highly variable. So the CO2 per shipper was estimated indirectly, with two different approaches: First we set up a typology of the shippers, in 10 types of ‘homogenous’ establishments and estimated in each type an average level of emissions per shipper. In a second approach, carbon intensity per tonne shipped has been modelled, using only the shipper characteristics as explaining variables. Then for each shipper, multiplying this average CO2 emission per ton…