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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Modelling vehicle emissions from an urban air-quality perspective:testing vehicle emissions interdependencies

Dabbas, Wafa M January 2010 (has links)
Doctor of Philosophy(PhD) / Abstract This thesis employs a statistical regression method to estimate models for testing the hypothesis of the thesis of vehicle emissions interdependencies. The thesis at the beginnings, reviews critically the formation of emissions in gasoline-fuelled engines, and also reviews existing and emerging models of automotive emissions. The thesis then, presents the relationships between the urban transport system and vehicle emissions. Particularly, it summarises different types of emissions and the contributory factors of the urban transport system to such emissions. Subsequently, the thesis presents the theory of vehicle emissions interdependencies and the empirical framework for testing the hypothesis of the thesis. The scope of testing the hypothesis of the thesis is only limited to gasoline-fuelled conventional vehicles in the urban transport environment. We use already available laboratory-based testing dataset of 542 passenger vehicles, to investigate the hypothesis of the thesis of vehicle emissions interdependencies. HC, CO, and NOX emissions were collected under six test drive-cycles, for each vehicle before and after vehicles were tuned. Prior to using any application, we transform the raw dataset into actionable information. We use three steps, namely conversion, cleaning, and screening, to process the data. We use classification and regression trees (CART) to narrow down the input number of variables in the models formulated for investigating the hypothesis of the thesis. We then, utilise initial results of the analysis to fix any remaining problems in the data. We employ three stage least squares (3SLS) regression to test the hypothesis of the thesis, and to estimate the maximum likelihood of vehicle variables and other emissions to influence HC, CO, and NOX emissions simultaneously. We estimate twelve models, each of which consists of a system of three simulations equations that accounts for the endogenous relations between HC, CO and NOX emissions when estimating vehicle emissions simultaneously under each test drive-cycle. The major contribution of the thesis is to investigate the inter-correlations between vehicle emissions within a well controlled data set, and to test the hypothesis of vehicle emissions interdependencies. We find that HC, CO, and NOX are endogenously or jointly dependent in a system of simultaneous-equations. The results of the analysis demonstrate that there is strong evidence against the null hypothesis (H0) in favour of the alternative hypothesis (H1) that HC, CO, and NOX are statistically significantly interdependent. We find, for the thesis sample, that NOX and CO are negatively related, whereas HC and CO emissions are positively related, and HC and NOX are positively related. The results of the thesis yield new insights. They bridge a very important gap in the current knowledge on vehicle emissions. They advance not only our current knowledge that HC, CO, and NOX should be predicted jointly since they are produced jointly, but also acknowledge the appropriateness of using 3SLS regression for estimating vehicle emissions simultaneously. The thesis measures the responses of emissions to changes with respect to changes in the other emissions. We investigate emission responses to a one percent increase in an emission with respect to the other emissions. We find the relationship between CO and NOX is of special interest. After vehicles were tuned, we find those vehicles that exhibit a one percent increase in NOX exhibit simultaneously a 0.35 percent average decrease in CO. Similarly, we find that vehicles which exhibit a one percent increase in CO exhibit simultaneously a 0.22 percent average decrease in NOX. We find that the responses of emission to changes with respect to other emissions vary with various test drive-cycles. Nonetheless, a band of upper and lower limits contains these variations. After vehicle tuning, a one percent increase in HC is associated with an increase in NOX between 0.5 percent and 0.8 percent, and an increase in CO between 0.5 percent and one percent Also, for post-tuning vehicles, a one percent increase in CO is associated with an increase in HC between 0.4 percent and 0.9 percent, and a decrease in NOX between 0.07 percent and 0.32 percent. Moreover, a one percent increase in NOX is associated with increase in HC between 0.8 percent and 1.3 percent, and a decrease in CO between 0.02 percent and 0.7 percent. These measures of the responses are very important derivatives of the hypothesis investigated in the thesis. They estimate the impacts of traffic management schemes and vehicle operations that target reducing one emission, on the other non-targeted emissions. However, we must be cautious in extending the results of the thesis to the modern vehicles fleet. The modern fleet differs significantly in technology from the dataset that we use in this thesis. The dataset consists of measurements of HC, CO, and NOX emissions for 542 gasoline-fuelled passenger vehicles, under six test drive-cycles, before and after the vehicles were tuned. Nevertheless, the dataset has a number of limitations such as limited model year range, limited representations of modal operations, and limitations of the measurements of emissions based only on averages of test drive-cycles, in addition to the exclusion of high-emitter emission measurements from the dataset. The dataset has a limited model year range, i.e., between 1980 and 1991. We highlight the age of the dataset, and acknowledge that the present vehicle fleet varies technologically from the vehicles in the dataset used in this thesis. Furthermore, the dataset has a limited number of makes - Holden, Ford, Toyota, Nissan, and Mitsubishi. There are also a limited number of modal operations. The model operations presented in the dataset are cold start, warming-up, and hot stabilised driving conditions. However, enrichment episodes are not adequately presented in the test-drive cycles of the dataset. Moreover, the dataset does not take into account driving behaviour influences, and all measurements are cycle-based averages. The emission measurements of laboratory-based testings are aggregated over a test drive cycle, and the test drive-cycle represents an average trip over an average speed. The exclusion of the measurements of high emitting vehicles from the dataset introduces further limitations. Remote sensing studies show that 20 percent of the on-road vehicle fleet is responsible for 80 percent of HC and CO emissions. The findings of the thesis assist in the identification of the best strategies to mitigate the most adverse effects of air-pollution, such as the most severe pollution that have the most undesirable pollution effects. Also, they provide decision-makers with valuable information on how changes in the operation of the transport system influence the urban air-quality. Moreover, the thesis provides information on how vehicle emissions affect the chemistry of the atmosphere and degrade the urban air-quality.
52

Modelling vehicle emissions from an urban air-quality perspective:testing vehicle emissions interdependencies

Dabbas, Wafa M January 2010 (has links)
Doctor of Philosophy(PhD) / Abstract This thesis employs a statistical regression method to estimate models for testing the hypothesis of the thesis of vehicle emissions interdependencies. The thesis at the beginnings, reviews critically the formation of emissions in gasoline-fuelled engines, and also reviews existing and emerging models of automotive emissions. The thesis then, presents the relationships between the urban transport system and vehicle emissions. Particularly, it summarises different types of emissions and the contributory factors of the urban transport system to such emissions. Subsequently, the thesis presents the theory of vehicle emissions interdependencies and the empirical framework for testing the hypothesis of the thesis. The scope of testing the hypothesis of the thesis is only limited to gasoline-fuelled conventional vehicles in the urban transport environment. We use already available laboratory-based testing dataset of 542 passenger vehicles, to investigate the hypothesis of the thesis of vehicle emissions interdependencies. HC, CO, and NOX emissions were collected under six test drive-cycles, for each vehicle before and after vehicles were tuned. Prior to using any application, we transform the raw dataset into actionable information. We use three steps, namely conversion, cleaning, and screening, to process the data. We use classification and regression trees (CART) to narrow down the input number of variables in the models formulated for investigating the hypothesis of the thesis. We then, utilise initial results of the analysis to fix any remaining problems in the data. We employ three stage least squares (3SLS) regression to test the hypothesis of the thesis, and to estimate the maximum likelihood of vehicle variables and other emissions to influence HC, CO, and NOX emissions simultaneously. We estimate twelve models, each of which consists of a system of three simulations equations that accounts for the endogenous relations between HC, CO and NOX emissions when estimating vehicle emissions simultaneously under each test drive-cycle. The major contribution of the thesis is to investigate the inter-correlations between vehicle emissions within a well controlled data set, and to test the hypothesis of vehicle emissions interdependencies. We find that HC, CO, and NOX are endogenously or jointly dependent in a system of simultaneous-equations. The results of the analysis demonstrate that there is strong evidence against the null hypothesis (H0) in favour of the alternative hypothesis (H1) that HC, CO, and NOX are statistically significantly interdependent. We find, for the thesis sample, that NOX and CO are negatively related, whereas HC and CO emissions are positively related, and HC and NOX are positively related. The results of the thesis yield new insights. They bridge a very important gap in the current knowledge on vehicle emissions. They advance not only our current knowledge that HC, CO, and NOX should be predicted jointly since they are produced jointly, but also acknowledge the appropriateness of using 3SLS regression for estimating vehicle emissions simultaneously. The thesis measures the responses of emissions to changes with respect to changes in the other emissions. We investigate emission responses to a one percent increase in an emission with respect to the other emissions. We find the relationship between CO and NOX is of special interest. After vehicles were tuned, we find those vehicles that exhibit a one percent increase in NOX exhibit simultaneously a 0.35 percent average decrease in CO. Similarly, we find that vehicles which exhibit a one percent increase in CO exhibit simultaneously a 0.22 percent average decrease in NOX. We find that the responses of emission to changes with respect to other emissions vary with various test drive-cycles. Nonetheless, a band of upper and lower limits contains these variations. After vehicle tuning, a one percent increase in HC is associated with an increase in NOX between 0.5 percent and 0.8 percent, and an increase in CO between 0.5 percent and one percent Also, for post-tuning vehicles, a one percent increase in CO is associated with an increase in HC between 0.4 percent and 0.9 percent, and a decrease in NOX between 0.07 percent and 0.32 percent. Moreover, a one percent increase in NOX is associated with increase in HC between 0.8 percent and 1.3 percent, and a decrease in CO between 0.02 percent and 0.7 percent. These measures of the responses are very important derivatives of the hypothesis investigated in the thesis. They estimate the impacts of traffic management schemes and vehicle operations that target reducing one emission, on the other non-targeted emissions. However, we must be cautious in extending the results of the thesis to the modern vehicles fleet. The modern fleet differs significantly in technology from the dataset that we use in this thesis. The dataset consists of measurements of HC, CO, and NOX emissions for 542 gasoline-fuelled passenger vehicles, under six test drive-cycles, before and after the vehicles were tuned. Nevertheless, the dataset has a number of limitations such as limited model year range, limited representations of modal operations, and limitations of the measurements of emissions based only on averages of test drive-cycles, in addition to the exclusion of high-emitter emission measurements from the dataset. The dataset has a limited model year range, i.e., between 1980 and 1991. We highlight the age of the dataset, and acknowledge that the present vehicle fleet varies technologically from the vehicles in the dataset used in this thesis. Furthermore, the dataset has a limited number of makes - Holden, Ford, Toyota, Nissan, and Mitsubishi. There are also a limited number of modal operations. The model operations presented in the dataset are cold start, warming-up, and hot stabilised driving conditions. However, enrichment episodes are not adequately presented in the test-drive cycles of the dataset. Moreover, the dataset does not take into account driving behaviour influences, and all measurements are cycle-based averages. The emission measurements of laboratory-based testings are aggregated over a test drive cycle, and the test drive-cycle represents an average trip over an average speed. The exclusion of the measurements of high emitting vehicles from the dataset introduces further limitations. Remote sensing studies show that 20 percent of the on-road vehicle fleet is responsible for 80 percent of HC and CO emissions. The findings of the thesis assist in the identification of the best strategies to mitigate the most adverse effects of air-pollution, such as the most severe pollution that have the most undesirable pollution effects. Also, they provide decision-makers with valuable information on how changes in the operation of the transport system influence the urban air-quality. Moreover, the thesis provides information on how vehicle emissions affect the chemistry of the atmosphere and degrade the urban air-quality.
53

Desenvolvimento de um espectrômetro por absorção diferencial para medidas de poluentes na atmosfera / Development of a spectrometer using the differential optical absorption spectroscopy for measures of pollutants in the atmosphere

Paulo Cesar de Souza 05 September 2007 (has links)
Este trabalho apresenta os resultados da construção de um espectrômetro utilizando a espectroscopia ótica por absorção diferencial (DOAS) para determinação de poluentes na atmosfera. A determinação e a quantificação de gases-traço contaminantes na atmosfera são possíveis pelo registro da transmitância, e posterior avaliação das estruturas de absorção características de cada espécie, em um caminho ótico aberto conhecido na atmosfera. As partes óticas e eletrônicas foram caracterizadas e o software de comando e processamento espectral foi desenvolvido. O sistema construído foi testado em laboratório e medidas de emissões veiculares de quatro automóveis foram realizadas. Os resultados das emissões veiculares apresentaram uma sensível diferença entre os veículos no regime de operação (motor frio e quente) por um fator que varia entre 5 e 8. / This work presents the results of the construction of a spectrometer using the differential optical absorption spectroscopy (DOAS) for determination of pollutants in the atmosphere. The determination and quantification of trace gas contaminations in atmosphere is possible by recording and later evaluation of characteristic absorption structures in a known path length in open atmosphere. The parts optics and electronic had been characterized and the software of command and spectral processing was developed. The system was built and tested in laboratory and vehicle emissions measures of four cars were performed. The results in vehicle emissions showed a noticeable difference between vehicles in the system of operation (hot and cold engine) by a factor ranging between 5 and 8.
54

Estudo dos efeitos dos elementos traços presentes nas partículas provenientes da queima do diesel no sistema reprodutivo de Danio rerio (zebrafisch): análise morfológica e histológica / Effects of trace elements present in diesel exhaust particulates in the reproductive system of Danio rerio (zebrafish): Morphological and histological analysis

Fabiana Moura Novaes Mendez 11 December 2012 (has links)
A qualidade do ar nas áreas urbanas tende a apresentar concentrações indesejáveis de contaminantes provenientes da queima de biomassa, não havendo um sistema abrangente de monitoramento. Achados in vivo mostram que o diesel pode conter compostos que modulam a atividade do estrógeno. Estudos in vitro apoiam essa ideia, como o estudo realizado com cloreto de metileno extraído do diesel que comprova atuar como ativadores de ligação para os receptores de estrógeno. Esse trabalho tem por objetivo avaliar o efeito da exposição à metais presentes nas partículas de exaustao de diesel (PED) na morfologia do ovaário através da histologia, e análise do padrão de expressão dos receptores de estrógeno (ERs) no ovário de zebrafish (Danio rerio) usando a metodologia de PCR em tempo real. Fêmeas adultas de zebrafish foram expostas à concentrações ambientais de combinado de metais (Ni = 0,181 mg/L ; Fe = 0,07455 mg/L ; Pb= 0,05 mg/ L; Cd = 0,029 mg/ L; Cr = 0,161 mg/L ; Cu = 0,017 mg / L) por 3 dias. Em relação a contagem de ovócitos atrésicos a média observada nos animais expostos foi de 1,5 ± 0,4 e nos controles foi de 1,34 ± 0,3. Contudo, não houve diferença significativa entre os grupos (p > 0,05). Na expressão dos três genes receptores de estrógeno (esr1, esr2a, esr2b) as médias foram: 0,68; 1,32; 0,54; respectivamente. No entanto, não houve alteração significativa na expressão desses genes em relação aos controles. Os elementos traços presentes nas PED em concentração ambiental e em exposição aguda na fase adulta não alteram a expressão dos ERs o também não afetam o número de folículos atrésicos nos ovários / The air quality in urban areas tends to have undesirable concentrations of contaminants from biomass combustion, without a monitoring system. In vivo findings show that diesel may contain compounds that modulate the activity of estrogen. In vitro studies support this idea, as the study with methylene chloride extract from diesel proves that this substance act as activators binding to the estrogen receptors (ERs). This study aims to evaluate the effect of exposure to metals present in diesel exhaust particles (PED) in ovary morphology through histology, and analysis of expression pattern of ERs in ovary of zebrafish (Danio rerio) using real time PCR metodology. Adult females were exposed to ambient concentrations of combined metals (Ni = 0.181 mg / L, Fe = 0.07455 mg / L Pb = 0,05 mg / L; Cd = 0.029 mg / L; = 0.161 mg Cr / L, Cu = 0.017 mg / L) for 3 days. The mean of atretic oocytes counting observed in animals exposed was 1.5 ± 0.4 and the controls was 1.34 ± 0.3. However, no significant difference between groups was observed (p> 0.05). The expression of the three genes estrogen receptor (esr1, esr2a, esr2b) mean were: 0.68, 1.32, 0.54, respectively. However, no significant change in the expression of these genes in relation to controls was observed. In conclusion, the trace elements present in the PED concentration in environmental and acute exposure in adulthood not alter the expression of ERs and does not affect the number of atretic follicles in the ovary
55

Cascas de árvores como biomonitores da poluição atmosférica de origem veicular em parques urbanos da cidade de São Paulo / Tree barks as biomonitors of traffic related air pollution in urban parks of the city of São Paulo

Ana Paula Garcia Martins 09 November 2009 (has links)
O presente estudo foi desenvolvido para caracterizar a área de influência dos corredores de tráfego, através do monitoramento da concentração de elementos-traço em cascas de árvores. Amostras (n = 98) de cascas de árvores de diversas espécies foram coletadas em cinco parques urbanos da cidade de São Paulo. Para controle, foram coletadas cascas de árvores numa zona rural de Embu-Guaçu, longe de tráfego ou de indústrias. As concentrações de Ba, Co, Cr, Cu, Fe, Ca, Pb, S e Zn foram determinadas nas amostras de cascas de árvores por espectrometria de fluorescência de raios-X. Amostras coletadas nos parques urbanos apresentaram níveis mais elevados de elementos-traço em comparação com as da região controle. Elementos relacionados a atividades antropogênicas exibiram maiores concentrações nas amostras coletads na periferia dos parques, diminuindo gradativamente para os seus centros. Áreas próximas a grandes avenidas ou próximas a semáforos e cruzamentos apresentaram maiores concentrações de elementos nas cascas. Em conclusão, o estudo mostrou que medidas de acúmulo de elementos traço em cascas de árvore, associadas a métodos geoestatísticos, podem auxiliar a determinação das zonas de maior influência da poluição veicular no cenário urbano / The present study was designed to characterize the area of influence of high traffic corridors by monitoring trace element concentrations on tree barks. Samples (n=98) of tree barks were collected from several tree species in five urban parks of the city of São Paulo. For controlling purposes, we collected tree barks in a rural area of Embu-Guaçu which is far from traffic or industries. Concentrations of Ba, Co, Cr, Cu, Fe, Ca, Pb, S and Zn were determined in these barks by X-ray fluorescence spectrometry. Samples from urban parks exhibited higher levels of trace elements in comparison with those from control region. Elements related to anthropogenic activities exhibited higher concentrations in tree barks at the periphery of the parks, decreasing when moving towards their centers. Areas facing the busy streets or those close to traffic lights or traffic junctions presented higher concentrations of elements in barks. In conclusion, the present study showed that measures of trace elements accumulation in tree barks within geostatistical methods can indicate areas of strong influence of vehicular pollution in the urban scene
56

Efeito da poluição do tráfego na pressão arterial dos agentes de trânsito em Santo André / Traffic air pollution effect in the blood pressure of traffic agents in Santo André, São Paulo, Brazil

Paulo Sérgio Chiarelli 16 October 2009 (has links)
A constante exposição à poluição do ar continua acometendo a saúde das populações, resultando num aumento da morbidade e mortalidade decorrente de problemas respiratórios e cardiovasculares. O estudo é transversal, com o objetivo de avaliar as modificações na pressão arterial sistêmica, e pressão de pulso, em indivíduos do gênero masculino, jovens, expostos à poluição do tráfego no município de Santo André, região metropolitana da Grande São Paulo - Brasil. Os níveis horários diários de poluentes do ar obtidos junto a Companhia de Tecnologia de Saneamento Ambiental do Estado de São Paulo (CETESB), as informações sobre temperatura e precipitação foram obtidas junto ao Instituto Nacional de Meteorologia (INMET). Foi realizada a análise descritiva de todas as variáveis do estudo. Foi utilizado o modelo de equação linear, tendo como variáveis dependentes a pressão arterial sistólica (PAS), pressão arterial diastólica (PAD) e pressão de pulso (PP), os poluentes do ar como vaiáveis independentes, e como variáveis de controle a temperatura mínima, precipitação, período de trabalho e período do dia. Foram analisados 19 agentes de tráfego do município de Santo André. A média de idade do grupo estudado foi de 42,8 (dp = 5,2) anos, variando entre 32 e 51 anos. Quanto ao IMC, temos que a média do grupo estudado foi de 25,2 (dp = 2,8), variando entre 19,2 e 29,4. Observa-se que para cada aumento de um interquartil no nível de PM10 (34g/m3) a PAS aumenta em 1,35 mmHg (IC95%: 0,40; 2,30), a PAD horária aumenta em 1,35 mmHg (IC95%: 0,57; 2,13), e a PP horária aumenta em 1,35 mmHg (IC95%: 0,40; 2,30) na hora de exposição. Os agentes de tráfego no município de Santo André apresentaram aumento da PAS, PAD e PP com a exposição ao PM10 e do O3. Os agentes de tráfego apresentaram aumentos nos níveis da pressão arterial e pressão de pulso com a exposição a poluição do ar em Santo André / The constant exposition to air pollution continues to cause the populations health problems, and its result an increase of morbidity and mortality by respiratory and cardiovascular diseases. This is a cross-sectional study which aims to assess the modifications in the systemic blood pressure and the pulse pressure in young male individuals, exposed to the traffic pollution in Santo André city, metropolitan region of the Greater São Paulo in Brazil. The hourly daily levels of air pollutants were obtained from the Technology Institute for the Environment and Sanitation of São Paulo State (CETESB), the information by temperature and precipitation was obtained from the National Meteorology Office (INMET). There has been carried out a descriptive analysis of all variables of the study. The linear equation model has been used, having as dependent variables the systolic blood pressure (SBP), the diastolic blood pressure (DBP) and the pulse pressure (PP), the air pollutants as independent variables, and as control variables the minimum temperature, precipitation, working period and day time. A number of 19 traffic agents in Santo André city have been analysed. The average age of the studied group was of 42.8 (sd = 5.2) years old, ranging from 32 to 51 years old. Concerning the BMI, we have got the information that the average of the studied group was of 25.2 (sd = 2.8), ranging from 19.2 to 29.4. It is observed that for an interquartile range increased in PM10 (34g/m3), the SBP increases in 1.35 mmHg (CI95%: 0.40; 2.30), the DBP increases in 1.35 mmHg (CI95%: 0.57; 2.13), and the PP increases in 1.35 mmHg (CI95%: 0.40; 2.30) at the exposure time. The traffic agents in Santo André city presented increase of SBP, DBP and PP with the exposure to PM10 and to O3. The traffic agents from Santo André presented higher arterial blood pressure and pulse pressure levels associated with the air pollution exposure in Santo André city
57

Modélisation de l’impact du trafic routier sur la pollution de l’air et des eaux de ruissellement / Modeling of air and stormwater pollution related to vehicular traffic

Fallah Shorshani, Masoud 04 July 2014 (has links)
Les émissions du trafic routier sont une des sources majeures de pollution dans les villes. La modélisation de la pollution de l'air et des eaux de ruissellement due aux émissions du trafic routier est essentielle pour comprendre les processus qui mènent à cette pollution et fournir les éléments d'information nécessaires au développement de politiques publiques efficaces pour la réduction des niveaux de pollution. L'objectif de cette thèse est d'évaluer la faisabilité et la pertinence de chaînes de modèles pour simuler l'impact du trafic routier sur la pollution de l'air et des eaux de ruissellement. La première partie a consisté à réaliser un état de l'art des outils de modélisation des différents phénomènes (trafic, émissions, pollution atmosphérique, qualité des eaux de ruissellement), mettant en exergue les enjeux liés à l'intégration des différents modèles pour constituer une chaîne cohérente en termes de polluants et d'échelles spatio-temporelles. Deux exemples de chaînes de modélisation ont été proposés, l'une statique avec des pas de temps horaires, la seconde envisageant une approche dynamique du trafic et des pollutions associées. Dans la deuxième partie de la thèse, des outils automatisés d'interfaçage ont été développés pour construire des chaînes de modèles. Ces chaînes de modèles ont ensuite été testées avec différents cas d'étude : (1) Couplage trafic / émissions avec une simulation d'une voie urbaine utilisant un modèle dynamique de trafic en lien avec des modèles d'émissions instantané et moyenné, (2) couplage émissions / pollution atmosphérique en bordure d'une autoroute, (3) couplages trafic / émissions / pollution atmosphérique en bordure d'une autoroute urbaine, (4) couplage émissions / pollution atmosphérique pour un quartier suburbain, (5) couplage dépôts atmosphériques / qualité des eaux de ruissellement pour un bassin versant suburbain, et finalement (6) une chaîne de modélisation complète avec couplages trafic / émissions /qualité de l'air et des eaux de ruissellement pour un bassin versant suburbain. Ces travaux ont permis à travers ces différents cas d'étude d'identifier les enjeux associés à l'intégration de modèles pour le calcul de la pollution de l'air et des eaux de ruissellement due au trafic routier en zone urbaine. Par ailleurs, ils fournissent une base solide pour le développement futur de modèles numériques intégrés de la pollution urbaine / Road traffic emissions are a major source of pollution in cities. Modeling of air and stormwater pollution due to on-road vehicles is essential to understand the processes that lead to the pollution and to provide the necessary information for the development of effective public policies to reduce pollution. The objective of this thesis is to evaluate the feasibility and relevance of modeling chains to simulate the impact of road traffic on air and stormwater pollution. The first part of the thesis consisted in assessing the state of the art of modeling tools available for the different relevant phenomena (traffic, emissions, atmospheric dispersion, and stormwater quality), highlighting challenges associated with the integration of the different models to create a consistent modeling chain in terms of pollutants and spatio-temporal scales. Two examples of modeling chains have been proposed, one static with hourly time-steps, the other based on a dynamic approach for traffic and its associated pollution. In the second part of the thesis, different interface tools have been developed to link models and construct modeling chains. These modeling chains were tested with different case studies: (1) coupling traffic and emissions for the simulation of an urban street using a dynamic model of traffic with instantaneous and time-averaged emission models, (2) coupling on-road emissions and atmospheric dispersion/deposition near a freeway, (3) coupling traffic, emissions and atmospheric dispersion/chemistry near a freeway, (4) coupling emissions and atmospheric dispersion/deposition in a suburban neighborhood (5) coupling atmospheric deposition and stormwater quality for an urban catchment, and finally (6) a complete modeling chain with traffic / emissions / air and stormwater quality models for urban catchment drainage. This work allows one to identify different possibilities of model integration to calculate air and stormwater pollution due to road traffic in urban areas. Moreover, it provides a solid basis for the future development of integrated numerical models of urban pollution
58

Efeito da poluição do tráfego na pressão arterial dos agentes de trânsito em Santo André / Traffic air pollution effect in the blood pressure of traffic agents in Santo André, São Paulo, Brazil

Chiarelli, Paulo Sérgio 16 October 2009 (has links)
A constante exposição à poluição do ar continua acometendo a saúde das populações, resultando num aumento da morbidade e mortalidade decorrente de problemas respiratórios e cardiovasculares. O estudo é transversal, com o objetivo de avaliar as modificações na pressão arterial sistêmica, e pressão de pulso, em indivíduos do gênero masculino, jovens, expostos à poluição do tráfego no município de Santo André, região metropolitana da Grande São Paulo - Brasil. Os níveis horários diários de poluentes do ar obtidos junto a Companhia de Tecnologia de Saneamento Ambiental do Estado de São Paulo (CETESB), as informações sobre temperatura e precipitação foram obtidas junto ao Instituto Nacional de Meteorologia (INMET). Foi realizada a análise descritiva de todas as variáveis do estudo. Foi utilizado o modelo de equação linear, tendo como variáveis dependentes a pressão arterial sistólica (PAS), pressão arterial diastólica (PAD) e pressão de pulso (PP), os poluentes do ar como vaiáveis independentes, e como variáveis de controle a temperatura mínima, precipitação, período de trabalho e período do dia. Foram analisados 19 agentes de tráfego do município de Santo André. A média de idade do grupo estudado foi de 42,8 (dp = 5,2) anos, variando entre 32 e 51 anos. Quanto ao IMC, temos que a média do grupo estudado foi de 25,2 (dp = 2,8), variando entre 19,2 e 29,4. Observa-se que para cada aumento de um interquartil no nível de PM10 (34g/m3) a PAS aumenta em 1,35 mmHg (IC95%: 0,40; 2,30), a PAD horária aumenta em 1,35 mmHg (IC95%: 0,57; 2,13), e a PP horária aumenta em 1,35 mmHg (IC95%: 0,40; 2,30) na hora de exposição. Os agentes de tráfego no município de Santo André apresentaram aumento da PAS, PAD e PP com a exposição ao PM10 e do O3. Os agentes de tráfego apresentaram aumentos nos níveis da pressão arterial e pressão de pulso com a exposição a poluição do ar em Santo André / The constant exposition to air pollution continues to cause the populations health problems, and its result an increase of morbidity and mortality by respiratory and cardiovascular diseases. This is a cross-sectional study which aims to assess the modifications in the systemic blood pressure and the pulse pressure in young male individuals, exposed to the traffic pollution in Santo André city, metropolitan region of the Greater São Paulo in Brazil. The hourly daily levels of air pollutants were obtained from the Technology Institute for the Environment and Sanitation of São Paulo State (CETESB), the information by temperature and precipitation was obtained from the National Meteorology Office (INMET). There has been carried out a descriptive analysis of all variables of the study. The linear equation model has been used, having as dependent variables the systolic blood pressure (SBP), the diastolic blood pressure (DBP) and the pulse pressure (PP), the air pollutants as independent variables, and as control variables the minimum temperature, precipitation, working period and day time. A number of 19 traffic agents in Santo André city have been analysed. The average age of the studied group was of 42.8 (sd = 5.2) years old, ranging from 32 to 51 years old. Concerning the BMI, we have got the information that the average of the studied group was of 25.2 (sd = 2.8), ranging from 19.2 to 29.4. It is observed that for an interquartile range increased in PM10 (34g/m3), the SBP increases in 1.35 mmHg (CI95%: 0.40; 2.30), the DBP increases in 1.35 mmHg (CI95%: 0.57; 2.13), and the PP increases in 1.35 mmHg (CI95%: 0.40; 2.30) at the exposure time. The traffic agents in Santo André city presented increase of SBP, DBP and PP with the exposure to PM10 and to O3. The traffic agents from Santo André presented higher arterial blood pressure and pulse pressure levels associated with the air pollution exposure in Santo André city
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Kartläggning & optimering av externa flöden ur ett hållbarhetsperspektiv : En fallstudie på Gestamp HardTech

Norgren, Malin, Lindberg, Elin January 2023 (has links)
In the pursuit of sustainable development, the transportation sector plays a crucial role by significantly contributing to greenhouse gas emissions. The purpose of this study is to examine how companies utilizing third-party logistics can compile and reduce transport-related emissions, more specifically investigating short- and long-term opportunities for the external flow of Gestamp HardTech in Luleå. Through a comprehensive analysis of available data, utilization of calculation models, and examination of short- and long-term opportunities, this research provides valuable insights and recommendations for companies seeking to promote sustainable transport solutions.  The findings underscore the importance of transparency, consistency, and leveraging available data as a reliable foundation for informed decision-making. Additionally, the study highlights the significance of selecting transportation companies that prioritize data utilization and offer green transportation alternatives. Additionally, staying updated on innovations within the field is vital, considering the dynamic nature of the transport industry and the potential for emerging technologies to reshape emission reduction strategies. It is important to note that while short- and long-term recommendations are provided, the ever-evolving landscape necessitates flexibility and continuous adaptation.
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The Effects of Urban Form on Vehicle Emissions - Focusing On Urban Form Factors and Three Conventional Air Pollutions and Carbon Dioxide -

Lee, Jae Choon 20 December 2012 (has links)
No description available.

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