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Publicações

Publicações por CESE

2014

Electronic government: Challenges for public services consumer behaviour and value creation

Autores
Moreira, AC; Zimmermann, RA;

Publicação
Handbook of Research on Managing and Influencing Consumer Behavior

Abstract
E-government has become a priority for many governments around the world and one of the main change drivers in the provision of new services in the public administration context. As public services are part of a complex network in which citizens are the main players, public authorities are increasingly trying to identify and deploy programmes that promote the modernisation and simplification of public services based on knowledge management. This chapter aims to understand the impact of e-government initiatives on consumer behaviour, as well as the importance of knowledge management for value creation in the public administration context. The Simplex programme, the main initiative in Portugal to develop administrative simplification and e-government, is analysed within two contexts: the central administration and the local municipality of Oporto. This chapter highlights that e-government has been an important factor contributing to both the administrative simplification and the improvement in the quality of public services.

2014

An eco-traffic management tool

Autores
Bandeira, JM; Pereira, SR; Fontes, T; Fernandes, P; Khattak, AJ; Coelho, MC;

Publicação
Advances in Intelligent Systems and Computing

Abstract
Drivers routing decisions can be influenced to minimize environmental impacts by using, for instance, dynamic and intelligent road pricing schemes. However, some previous research studies have shown that often different pollutants can dictate different traffic assignment strategies which makes necessary to assign weights to these pollutants so they become comparable. In this chapter, a tool for traffic assignment taking into account eco-routing purposes is presented. The main goal of this work is to identify the best traffic volume distribution that allows a minimization of environmental costs for a given corridor with predetermined different alternative routes. To achieve this, an integrated numerical computing platform was developed by integrating microscopic traffic and emission models. The optimization tool employs non-linear techniques to perform different traffic assignment methods: User Equilibrium (UE), System Optimum (SO) and System Equitable (SE). For each method, different strategies can be assessed considering: (i) individual pollutants and traffic performance criteria; and (ii) all pollutants simultaneously. For the latter case, three different optimization approaches can be assessed based on: (i) economic costs of pollutants once released into the air; (ii) human health impacts according to the Eco-Indicator 99; and (iii) real time atmospheric pollutant concentration levels. The model was applied to a simple network, simulating three levels of traffic demand and three different strategies for traffic assignment. The system is developed in Microsoft Excel and offers a user friendly access to optimization algorithms by including a dynamic user interface. © Springer International Publishing Switzerland 2014.

2014

Are HOV/eco-lanes a sustainable option to reducing emissions in a medium-sized European city?

Autores
Fontes, T; Fernandes, P; Rodrigues, H; Bandeira, JM; Pereira, SR; Khattak, AJ; Coelho, MC;

Publicação
TRANSPORTATION RESEARCH PART A-POLICY AND PRACTICE

Abstract
Innovative traffic management measures are needed to reduce transportation-related emissions. While in Europe, road lane management has focused mainly on introduction of bus lanes, the conversion to High Occupancy Vehicles (HOV) and eco-lanes (lanes dedicated to vehicles running on alternative fuels) has not been studied comprehensively. The objectives of this research are to: (1) Develop an integrated microscopic modeling platform calibrated with real world data to assess both traffic and emissions impacts of future Traffic Management Strategies (TMS) in an urban area; (2) Evaluate the introduction of HOV/eco-lanes in three different types of roads, freeway, arterial and urban routes, in an European medium-sized city and its effects in terms of emissions and traffic performance. The methodology consists of three distinct phases: (a) Traffic and road inventory data collection; (b) Traffic and emissions simulation using an integrated platform of microscopic simulation; and (c) Evaluation of scenarios. For the baseline scenario, the statistical analysis shows valid results. The results show that HOV and eco-lanes in a medium European city are feasible, and when the Average Occupancy of Vehicles (AOV) increases, on freeways, the majority of vehicles can reduce their travel time (2%) with a positive impact in terms of total emissions (-38% NOx, -39% HC, -43% CO and -37% CO2). On urban and arterial corridors, the reduction in emissions could be achieved only if the AOV increases from 1.50 to 1.70 passengers/vehicle. Total emissions of the corridor with an AOV of 1.70 passengers/vehicle can be reduced up to 35-36% for the urban route while the values can be reduced by 36-39% for the arterial road. With the introduction of Hybrid Electric Vehicles (HEV) and Electric Vehicles (EV) it is possible to reduce emissions, although the introduction of eco-lanes did not show significant reductions in emissions. When both policies are simulated together, an emissions improvement is observed for the arterial route and for two of the scenarios.

2014

Assessing the importance of vehicle type for the implementation of eco-routing systems

Autores
Bandeira, JM; Fontes, T; Pereira, SR; Fernandes, P; Khattak, A; Coelho, MC;

Publicação
17TH MEETING OF THE EURO WORKING GROUP ON TRANSPORTATION, EWGT2014

Abstract
Nowadays, several methods to promote a more sustainable distribution of traffic flows are available. In response to rising energy costs and increased environmental concerns, eco-friendly route choices can be provided individually by means of smart navigation tools that allow several vehicle routing options designed to minimize air pollutant emissions and fuel consumption. Simultaneously, the use of intelligent road pricing systems and the use of variable message signs can change the route choice process of drivers (and thus network equilibrium), by varying the perceived attributes of competing routes. However, so far too little attention has been paid to the fact that the ecofriendliness of various routes may change, depending on vehicle characteristics which may cause problems on the efficiency of these systems. This issue has been empirically addressed in this research, using a database of more than 13,330 km of GPS data in six different Origin-Destination (OD) pairs and 9 different routes. Simultaneously, two different approaches for estimating (CO2, HC, CO, NOx) emissions were tested: a) second-by-second vehicle dynamics, using the Vehicle Specific Power (VSP) instantaneous model; and b) route average speed using the EMEP/PEA methodology. The results show that depending on the characteristics of the routes associated with a certain OD pair, the eco-friendly route may differ according to the vehicle model and the emissions estimation method. Innovative approaches to provide accurate emissions and eco-routing information are needed.

2014

Assessment of potential improvements on regional air quality modelling related with implementation of a detailed methodology for traffic emission estimation

Autores
Coelho, MC; Fontes, T; Bandeira, JM; Pereira, SR; Tchepel, O; Dias, D; Sa, E; Amorim, JH; Borrego, C;

Publicação
SCIENCE OF THE TOTAL ENVIRONMENT

Abstract
The accuracy and precision of air quality models are usually associated with the emission inventories. Thus, in order to assess if there are any improvements on air quality regional simulations using detailed methodology of road traffic emission estimation, a regional air quality modelling system was applied. For this purpose, a combination of top-down and bottom-up approaches was used to build an emission inventory. To estimate the road traffic emissions, the bottom-up approach was applied using an instantaneous emission model (Vehicle Specific Power - VSP methodology), and an average emission model (CORINAIR methodology), while for the remaining activity sectors the top-down approach was used. Weather Research and Forecasting (WRF) and Comprehensive Air quality (CAMx) models were selected to assess two emission scenarios: (i) scenario 1, which includes the emissions from the top-down approach; and (ii) scenario 2, which includes the emissions resulting from integration of top-down and bottom-up approaches. The results show higher emission values for PM10, NOx and HC, for scenario 1, and an inverse behaviour to CO. The highest differences between these scenarios were observed for PM10 and HC, about 55% and 75% higher (respectively for each pollutant) than emissions provided by scenario 2. This scenario gives better results for PM10, CO and O-3. For NO2 concentrations better results were obtained with scenario 1. Thus, the results obtained suggest that with the combination of the top-down and bottom-up approaches to emission estimation several improvements in the air quality results can be achieved, mainly for PM10, CO and O-3.

2014

Can artificial neural networks be used to predict the origin of ozone episodes?

Autores
Fontes, T; Silva, LM; Silva, MP; Barros, N; Carvalho, AC;

Publicação
SCIENCE OF THE TOTAL ENVIRONMENT

Abstract
Tropospheric ozone is a secondary pollutant having a negative impact on health and environment. To control and minimize such impact the European Community established regulations to promote a clean air all over Europe. However, when an episode is related with natural mechanisms as Stratosphere-Troposphere Exchanges (STE), the benefits of an action plan to minimize precursor emissions are inefficient. Therefore, this work aims to develop a tool to identify the sources of ozone episodes in order to minimize misclassification and thus avoid the implementation of inappropriate air quality plans. For this purpose, an artificial neural network model the Multilayer Perceptron - is used as a binary classifier of the source of an ozone episode. Long data series, between 2001 and 2010, considering the ozone precursors, Be-7 activity and meteorological conditions were used. With this model, 2-7% of a mean error was achieved, which is considered as a good generalization. Accuracy measures for imbalanced data are also discussed. The MCC values show a good performance of the model (0.65-0.92). Precision and F-1-measure indicate that the model specifies a little better the rare class. Thus, the results demonstrate that such a tool can be used to help authorities in the management of ozone, namely when its thresholds are exceeded due natural causes, as the above mentioned STE. Therefore, the resources used to implement an action plan to minimize ozone precursors could be better managed avoiding the implementation of inappropriate measures.

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