An integrated GPS/PDA/GIS telegeoprocessing system for traffic & environment

The development of sustainable urban transport networks is a present priority for world leaders, national governors and local authorities. The challenge is to increase mobility reducing the adverse impacts of transport. The potential of Intelligent Transportation Systems (ITS) to provide solutions for the 21st century sustainable urban transport system has already been demonstrated in several piecewise applications. An integrated framework that addresses the needs of municipal authorities, that integrates the data spread through different sources, that supports the intelligent traffic & environment operations, and that provides information to the citizens steering their involvement and commitment is of critical importance and can be the enabler towards the creation of more efficient, safety, and environmental-friendly transport networks that promote the citizens’ quality of life. This work describes an integrated GPS (Global Positioning System) / PDA (Personal Digital Assistant) / GIS (Geographical Information System) system which is part of the mentioned framework. The system includes prototypes for mobile urban traffic data acquisition, with a GPS -equipped vehicle, a PDA application and wireless communications, and for a geodatabase with a related Web application for urban traffic & environment. Their integrated operation is exemplified for a real urban transport system.Postprint (published version

Congestion Indicators and Congestion Impacts: A Study on the Relevance of Area-wide Indicators

AbstractCongestion indicators for monitoring congestion in road area networks have been devised to use the output of long-term planning models which makes them insensitive to the dynamics of congestion or pollutant emissions. The objective of the present study is to compare the capabilities of different congestion indicators for describing congestion impacts (delays and emissions) considering a dynamic framework analysis. Microsimulation is used for estimating the congestion indicators as well as the congestion impacts in a disaggregated and dynamic mode. The indicators with the best descriptive capabilities are identified. Recommendations about indicators are provided for road practitioners. © 2011 Published by Elsevier Ltd

A Case Study on Reducing Traffic Congestion–Proposals to Improve Current Conditions

Traffic congestion has been considered one of the most serious global issues confronting all nations in recent years. Basrah City’s highways in general, and particularly the highways surrounding and leading to the University of Basrah, the campus of Bab Azzubair, and the college complex, have experienced traffic congestion and higher delays. The focus of this study is to propose some solutions to mitigate traffic congestion and higher delays on these highways. Field traffic data and questionnaires where SPSS was used to analyse the collected data, and Highway Capacity Software (HCS 2010) was used to assess the level of service (LOS) on the highways. The results showed that the LOS reaches level F on Baghdad Street, while other streets range from level B to level C. Two proposals have been suggested to improve the LOS on Baghdad Street: (1) applying a park-and-ride system; and (2) widening Baghdad Street by adding two lanes in each direction. The LOS for both proposals has been evaluated, and the results showed that the first proposal performed better. The analysis of the collected data also showed that public transportation services are very limited on the highways surrounding and leading to the Bab Azzubair campus. Therefore, public transportation services should be promoted and enhanced in Basrah City. Doi: 10.28991/CEJ-2023-09-10-07 Full Text: PD

Comparasion of road traffic emission models in Madrid (Spain)

Many cities in Europe have difficulties to meet the air quality standards set by the European legislation, most particularly the annual mean Limit Value for NO2. Road transport is often the main source of air pollution in urban areas and therefore, there is an increasing need to estimate current and future traffic emissions as accurately as possible. As a consequence, a number of specific emission models and emission factors databases have been developed recently. They present important methodological differences and may result in largely diverging emission figures and thus may lead to alternative policy recommendations. This study compares two approaches to estimate road traffic emissions in Madrid (Spain): the COmputer Programme to calculate Emissions from Road Transport (COPERT4 v.8.1) and the Handbook Emission Factors for Road Transport (HBEFA v.3.1), representative of the ‘average-speed’ and ‘traffic situation’ model types respectively. The input information (e.g. fleet composition, vehicle kilometres travelled, traffic intensity, road type, etc.) was provided by the traffic model developed by the Madrid City Council along with observations from field campaigns. Hourly emissions were computed for nearly 15 000 road segments distributed in 9 management areas covering the Madrid city and surroundings. Total annual NOX emissions predicted by HBEFA were a 21% higher than those of COPERT. The discrepancies for NO2 were lower (13%) since resulting average NO2/NOX ratios are lower for HBEFA. The larger differences are related to diesel vehicle emissions under “stop & go” traffic conditions, very common in distributor/secondary roads of the Madrid metropolitan area. In order to understand the representativeness of these results, the resulting emissions were integrated in an urban scale inventory used to drive mesoscale air quality simulations with the Community Multiscale Air Quality (CMAQ) modelling system (1 km2 resolution). Modelled NO2 concentrations were compared with observations through a series of statistics. Although there are no remarkable differences between both model runs, the results suggest that HBEFA may overestimate traffic emissions. However, the results are strongly influenced by methodological issues and limitations of the traffic model. This study was useful to provide a first alternative estimate to the official emission inventory in Madrid and to identify the main features of the traffic model that should be improved to support the application of an emission system based on “real world” emission factors

Impact of public transport strikes on traffic and pollution in the city of Barcelona

Altres ajuts: Acord transformatiu CRUE-CSICThis work has been supported by the Barcelona Council (20S01909-001). Jordi Perdiguero thanks the finantial support of Secretaria d'Universitats i Recerca del departament d'Empresa i Coneixement de la Generalitat de Catalunya (2020 PANDE 00058).Many Spanish cities' air contains excessive levels of pollutants caused by traffic. These pollutants are associated with high concentrations of vehicles in urban and surrounding areas, such as Madrid and Barcelona. According to the World Health Organization (WHO), 96.8% of Spain's population breathe polluted air. This paper provides empirical evidence on the effect of public transport strikes on Barcelona's air quality through an econometric analysis. The period analyzed included 147 days of some kind of public transport strike: bus (57), metro (21), trains (71), and tram (4); and also four general strikes. The estimates show that public transport strikes increases the concentration level of SO2, CO, PM, and NOX throughout the city, especially in the case of metro and RENFE trains. These results also allow us to understand how commuters substitute transport modes and to propose specific policies to increase public transport use

Advanced impact integration platform for cooperative road use

In order to improve networks efficiency, a considerable number of studies has been addressing the potential of eco-friendly assignment solutions as alternative approaches to reduce emissions and/or fuel use. So far the majority of studies generally assumes that the most eco-friendly solutions are the ones that minimize the absolute amount of emissions produced along a certain trip. In this work a platform based on both empirical GPS data and microscopic simulation models of traffic, emissions, noise, and road safety was developed to examine in depth 4 routes of an origin-destination pair over a Portuguese city. In addition to the integrated externalities assessment based on state of the art techniques, a novelty of this work was the preliminary inclusion of social criteria in defining sustainable assignment solutions. This paper provides new insights about sustainable traffic management issues and addresses multiple novel route choice indicators. Specifically we found that the relative variation of the individual costs and total pollution produced among 4 routes varies to a factor of 1.4 while the variation of the potentially exposed population ranges up to a factor of 10. The main results confirm the need to take into account real-time urban activity patterns in order to effectively implement sustainable traffic management measures

Exploring multiple eco-routing guidance strategies in a commuting corridor

The introduction of eco-routing systems has been suggested as a promising strategy to reduce carbon dioxide emissions and criteria pollutants. The objective of this study is to scrutinize the impacts of an eco-routing guidance system on emissions through the use of a case study in a commuting corridor. This research aims at assessing the potential environmental benefits in terms of different pollutant emissions. Simultaneously, it addresses the extent of variations in system travel time that each eco-routing strategy implies. The methodology consists of three distinct phases. The first phase corresponded to the adjustment of a micro simulation platform of traffic and emissions with empirical data previously collected. Secondly, volume-emission-functions (VEF) were developed based on the integrated modelling structure. Finally, different scenarios of traffic flow optimization were performed at the network level based on a simplified assignment procedure. The results show that if the traffic assignment is performed with the objective of minimize overall impacts, total system environmental damage costs can be reduced up to 9% with marginal oscillations in total system travel time. However, if drivers are advised based on their own emissions minimization, total system emissions may be higher than under the standard user equilibrium flow pattern. Specifically, environmentally friendly navigation algorithms focused on individual goals may tend to do divert traffic to roads with less capacity affecting the performance of the remaining traffic. This case study brings new insights about the difficulties and potentials of implementing such systems