Search results for "VSP methodology"
showing 3 items of 3 documents
Estimating pollutant emissions based on speed profiles at urban roundabouts: A pilot study
2019
The paper describes the pilot study conducted to assess the feasibility of the empirical approach utilizing vehicle trajectory data from a smartphone app and the Vehicle-Specific Power methodology to estimate pollutant emissions at urban roundabouts. The goal of this research phase is to acquire instantaneous speed data from a sample of six roundabouts located in the road network of the City of Palermo, Italy, and quantify emissions generated by the test vehicle through the examined roundabouts. For the case studies of roundabouts acceleration events in the circulating and exiting areas contributed to about 25% of the emissions for a given speed profile. More in general, the results from th…
Environmental Performance Evaluation at Urban Roundabouts
2021
Transformation toward greener, healthier and safer management of urban mobility demand is needed soon. Smart tools are available to assess the impact of new infrastructural projects and road facilities also from an environmental point of view. In this pilot study pollutant emissions at a sample of urban roundabouts were estimated employing the Vehicle Specific Power methodology which needs second-by-second speed profiles both gathered in the field and simulated in AIMSUN. The versatility of the micro-simulation model for a calibration aimed at improving accuracy of the emissions estimates was tested in order to ensure that second-by-second trajectories experienced in the field properly refl…
Environmental Performance Assessment of Urban Roundabouts
2021
To meet continuous and sustainable improvement on road infrastrucutures, new technologies and smart devices are encouraging the development of a mobile crowdsensing system for collecting and monitoring data to be used in efficiency assessment. In this view, the paper proposes a methodological approach that employs in an integrated way vehicle trajectory data collected in the field, the Vehicle Specific Power methodology and a microscopic traffic simulation model for estimating emissions at urban roundabouts. For a first characterization of the emissive phenomenon reference was made to an existing two-lane roundabout in Palermo, Italy, where vehicle trajectory data were collected using a sma…