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- Influence of Pedestrian Trajectories on School Children Exposure to PM10Publication . Garcia, João; Cerdeira, Rita; Coelho, Luis Manuel Rodrigues; Kumar, P.; Carvalho, Maria da Graça
- Developing a methodology to predict PM10 concentrations in urban areas using Generalized Linear Models.Publication . Garcia, João; Teodoro, F.; Cerdeira, Rita; Coelho, Luis Manuel Rodrigues; Kumar, Prashant; Carvalho, M. G.A methodology to predict PM10 concentrations in urban outdoor environments is developed based on the generalized linear models (GLMs). The methodology is based on the relationship developed between atmospheric concentrations of air pollutants (i.e. CO, NO2,NOx, VOCs, SO2) and meteorological variables (i.e. ambient temperature, relative humidity (RH) and wind speed) for acity (Barreiro) of Portugal. The model uses air pollution and meteorological data from thePortuguese monitoring air quality station networks. The developed GLM considers PM10 concentrations as a dependent variable, and both the gaseous pollutants and meteorological variables as explanatory independent variables. A logarithmic link function was considered with a Poisson probability distribution. Particular attention was given to cases with air temperatures both below and above 25°C. The best performance for modelled results against the measured data was achieved for the model with values of air temperature above 25°C compared with themodel considering all ranges of air temperatures and with the model considering only temperature below 25°C. The model was also tested with similar data from another Portuguese city, Oporto, and results found to behave similarly. It is concluded that this model and the methodology could be adopted for other cities to predict PM10 concentrations when these data are not available by measurements from air quality monitoring stations or other acquisition means
- Influence of virtual changes in buildingconfigurations of a real street canyon on thedispersion of PM10Publication . Garcia, João; Cerdeira, Rita; Tavares, Nelson; Coelho, Luis Manuel Rodrigues; Kumar, Prashant; Carvalho, M. G.Four geometrical configurations of a real street canyon in Barreirocity (Portugal) are considered to study their influence on the dis-persion of PM10. These configurations include actual architectural layout of the street (Option 1), and three virtual cases (Options1–3). Option 2 includes the modification of real geometry byincluding 4 m gaps between the buildings situated on the southern part of the street canyon. Option 3 considers 6 m gaps betweenbuildings as opposed to 4 m gaps in Option 2. Option 4 assumesthe same height for all buildings on the southern part of the street canyon, with no gaps between buildings. Computational fluid dynamics code (CFD), FLUENT, is used to simulate the detailed flow and turbulence characteristics in three-dimensional domain ofchosen street canyon, together with the PM10 dispersion for both the summer and winter seasons. The modelled PM10 concentra-tions were then compared with the measured data at seven differ-ent locations in the street canyon. Our results indicate up to 23%lower PM10concentrations at 1.5 m above the road level during the along-canyon wind direction due to the channelling of flow,compared with those observed during the cross-canyon wind direction. Detailed inspection of the results obtained from the Options 1–3 indicated that the spacing between the buildings tendto increase particle dilution during the cross-canyon winds resulting in up to 20, and 22% reduced concentrations for options 2,and 3 respectively, compared with the actual configuration (Option1). The largest improvement ( 7%) in the PM10concentrations wasgiven by Option 2, while other options showed modest changes.Possible reasons for these changes under varying meteorological conditions are explained in the context of changing building con-figurations and their implications in city planning.
- Developing a methodology to predict PM10 Urban Concentrations using GLM.Publication . Garcia, João; Teodoro, F.; Cerdeira, Rita; Coelho, Luis Manuel Rodrigues; Carvalho, Maria da Graça
- Relating air Pollution and Respiratory Diseases Occurrences.Publication . Teodoro, F.; Garcia, J.; Coelho, Luis Manuel Rodrigues; Carvalho, Maria da Graça
- Relating air Pollution and Respiratory Diseases OccurrencesPublication . Teodoro, M. F.; Garcia, J. N.; Coelho, Luis Manuel Rodrigues; Carvalho, M. G.In this article we study the impact of air pollution on children's health in Portugal. In particular, we focus our attention on the city of Barreiro. We use the general linear methods (GLM), taking advantage of all the ease of handling and analyzing data in order to relate air quality and health. We relate levels of air pollution and incidence of entries from children with symptoms of respiratory problems in the pediatric urgency service at the hospital of Barreiro. It was not easy to obtain clear and unambiguous relations in particle dispersion, air quality and health. A set of models are estimated by GLM and validated using adequate tests and residual analysis. At the end of this process, we combine the best models. The work is still going on.
- Empirical study of air quality in Barreiro city.Publication . Garcia, João; Teodoro, F.; Coelho, Luis Manuel Rodrigues; Carvalho, Maria da Graça
- Studying street geometry influence in PM10 concentrationPublication . Garcia, João; Cerdeira, Rita; Tavares, Nelson; Coelho, Luis Manuel Rodrigues
- Analysis of Pedestrian Short-Term Exposure on a High Traffic City StreetPublication . Garcia, João; Cerdeira, Rita; Tavares, Nelson; Coelho, Luis Manuel Rodrigues; Carvalho, M. G.
- Developing a methodology to predict PM10 urban concentrations using GLMPublication . Garcia, João; Teodoro, F.; Cerdeira, Rita; Coelho, Luis Manuel Rodrigues; Carvalho, Maria da Graça