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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
- Analysis of temporal lag in the impact of air quality on the health of children, in BarreiroPublication . Garcia, João; Cerdeira, Rita; Coelho, Luis Manuel RodriguesThe aim of this work was to study the impact of temporal lag between the exposition to air pollutants and the children admitted to the emergency room of Hospital Na Sra Rosário pediatric service, in Barreiro, Portugal, with symptoms of respiratory problems. The two variables were recorded by the medical staff and by an air quality monitoring station, in the same periods. From the results, a moderate correlation between different symptoms of respiratory diseases (sdr, cough, and asthma) and pollutants was found, reaching maximum values after temporal lags of 2 to 6 days. The strongest correlation for lag 0 (consequences on the same day) rises for the symptomatology of asthma, reaching the highest values for COmax (ρ = 0.26) and COpeak (ρ = 0.25). Also, an important correlation was found for NOx, NOx med and peak NOx (ρ = 0, 21). The correlation with PM10 shows an unrepresentative value (ρ = 0.09), being negative for O3max (ρ = 0.23) and O3peak (ρ = 0.22), as well as for SO2med (ρ = 0.12). Considering temporal lags of 1 to 8 and 15 days, overall, the maximum correlations between symptoms and NO, NO2, NOx, CO, and PM10 occur after temporal lags of 2 to 6 days, being constant or negative to SO2 and O3.
- 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
- 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
- Applying computational fluid dynamics in the development of smart ripening rooms for traditional cheesesPublication . Alvarenga, Nuno; Martins, João; Caeiro, José; Garcia, João; Passáro, João; Coelho, Luis Manuel Rodrigues; Santos, Maria Teresa; Lampreia, Célia; Martins, António; Dias, JoãoTraditional ewe’s cheese producers face certain challenges caused by fluctuating envi- ronmental parameters inside the ripening room, which lead to lack of homogeneity in the final product. The present research discusses the application of computer fluid dynamics for simulating the distribution of environmental parameters, predicting the airflow pattern, and identifying critical areas where such parameters could cause reduced cheese quality. A new monitoring system was developed including presence sensors, temperature and humidity dataloggers, pneumatic actua- tors, microcontrollers, and microcomputers connected remotely for control, data visualization, and processing. The validation of the computer simulation and monitoring system was made with a batch of 40 ewe’s cheeses distributed in three different zones inside a prototype ripening room and ripened for 35 days. At 35 days, a physical, chemical, and microbiological characterization of cheeses was made for evaluation of the influence of environmental conditions on cheese quality. The comparison between simulated and local measurements showed close agreement, especially concerning air velocity inside the stacks of cheese. The results of Pearson’s correlation analysis and PCA concluded that temperature affected the appearance of the rind, hardness, number and area occupied by holes. Humidity affected aw and mFeret. Air velocity affected pH and the circularity of gas holes.
- 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