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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.
521

Caracterização do material particulado fino e grosso e composição da fração inorgânica solúvel em água em São José dos Campos (SP)

Souza, Patrícia Alexandre de 24 October 2017 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-10-24T12:57:59Z No. of bitstreams: 1 PATRICIA_DISSETAÇÃO_MESTRADO_GEOQUIMICA_2009.pdf: 4047978 bytes, checksum: b2a1f62ef245a5a0d8afcc3ae828bf17 (MD5) / Made available in DSpace on 2017-10-24T12:57:59Z (GMT). No. of bitstreams: 1 PATRICIA_DISSETAÇÃO_MESTRADO_GEOQUIMICA_2009.pdf: 4047978 bytes, checksum: b2a1f62ef245a5a0d8afcc3ae828bf17 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Fundação de Amparo a Pesquisa do Estado do Rio de Janeiro / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / A cidade de São José dos Campos localizada no Vale do Paraíba é considerada uma área altamente suscetível à poluição do ar devido à geografia desta região, caracterizada por cadeias montanhosas que dão origem a Serra do Mar e Mantiqueira, dificultando a circulação geral da atmosfera e comprometendo a dispersão de poluentes atmosféricos bem como às emissões industriais de alto potencial poluidor proveniente dos parques industriais existente na região e suas vizinhanças. O objetivo do trabalho é caracterizar o material particulado atmosférico fino (PM2,5) e grosso (PM2,5-10) e determinar a composição química dos constituintes inorgânicos solúveis em água associados a estas partículas. As amostras de PM2,5 e PM2,5-10 foram coletadas semanalmente, em período contínuo de 24 h, por intermédio de um amostrador Dicotômico PM10 Sierra-Andersen em São José dos Campos entre fevereiro de 2004 a fevereiro de 2005 totalizando 60 amostragens. As concentrações médias anuais ± desvio padrão de PM2,5 e PM2,5-10 foram respectivamente iguais a 15,7 ± 7,9 e 14,8 ± 8,4 μg m-3. As maiores concentrações de particulado fino e grosso ocorreram no período de estiagem, enquanto que as concentrações mais baixas no período de chuvas, evidenciando o papel fundamental das chuvas na limpeza da atmosfera . Os íons NH4 + e SO4 2- ocorreram predominantemente no particulado fino correspondendo a 62% do total dos constituintes e 20 % da massa; por outro lado, os íons Cl-, Na+ e NO3 - predominaram no particulado grosso equivalendo, juntos, a 54 % dos íons inorgânicos e 11% da massa. Em média, 96% do SO4 2- associado ao PM2,5 equivale ao excesso de SO4 2-, ou seja, a outras fontes naturais e/ou antrópicas não provenientes do sal do mar. A razão NH4 +/ (Exc-SO4 2- + NO3 -) encontrada no PM2,5 igual a 1,08 sugere a formação de aerossóis de (NH4)2SO4 e NH4NO3 provenientes de atividades antrópicas. O déficit médio de cloreto foi de 42% para o PM2,5 e de 39% para o PM2,5-10. O déficit de Cl- para o PM2,5 durante o período de estiagem foi 4 vezes maior do que no período de chuvas, sendo o mesmo não observado para o PM2,5-10. Mais de 90% do K+, Ca2+ e Mg2+ encontrados em ambas as frações finas e grossas representa a parcela não-marinha (natural e/ou antrópica) destes íons. A modelagem hysplit para as retrotrajetórias de massas de ar auxiliou na identificação de episódios de transporte a longa distância, de material particulado de procedência continental e marítima em amostras que apresentaram composição química extremamente alta. A distribuição de chuvas ao longo do período de estudo, foi fundamental para o entendimento do comportamento sazonal das partículas atmosféricas finas e grossas em São José dos Campos. / São José dos Campos, located in the Paraíba Valley, is an area considered highly susceptible to air pollution because of its geography, characterized by mountain ranges that result in Serra do Mar and Mantiqueira, disturbing the general circulation of the atmosphere and threatening the dispersion of air pollutants as well as the high pollution potential emissions from industrial parks that exist in the region and in neighborhood. The objective of this study is to characterize the atmospheric fine (PM2,5) and coarse particulate (PM2,5-10) matter and determine the chemical composition of water-soluble inorganic constituents of these particles. The samples of PM2,5 and PM2,5-10 were weekly collected, in a continuous period of 24 hours with a PM10 dichotomic Sierra-Andersen sampler in São José dos Campos between February 2004 and February 2005, totalizing 60 samples. The annual average concentrations ± standard deviation of PM2,5 and PM2,5-10 were, respectively, 15,7 ± 7,9 and 14,8 ± 8,4 μg m-3. The highest concentrations of fine and coarse particulate matter occurred in the period of drought while lower concentrations were found in rainy period, highlighting the fundamental role of rain in cleaning the atmosphere. NH4 + and SO4 2- ions occurred predominantly in fine particulate matter corresponding to 62% of all constituents and 20% of the mass, on the other hand, Cl-, Na+ and NO3 - ions predominated in coarse particulate matter together amounting 54% of inorganic ions and 11% of the mass. On average 96% of the SO4 2- associated with PM 2,5 equal the Exc-SO4 2-, i.e. other natural and/or anthropic sources not from saltwater. The reason NH4 + / (Exc-SO4 2- + NO3 -) found in PM2,5 equals 1.08 suggesting the formation of (NH4)2SO4 and NH4NO3 aerosols from human activities. The average deficit of chloride was 42% for PM2,5 and 39% for PM2,5-10. The deficit of Cl- for PM2,5 during the drought period was 4 times higher than the one found in the rainy period, the same was not observed for PM 2,5-10. Over 90% of K+, Ca2+ and Mg2+ found in both fine and coarse fractions represent the non-marine parcel (natural and/or antropic) of those ions. The modeling hysplit for air masses retrotrajectories helped identifying long-distance transport episodes, particulate matter of continental and marine origin in samples that showed extremely high chemical composition. The distribution of the rain throughout the study was fundamental for understanding the seasonal behavior of atmospheric fine and coarse particles in Sao Jose dos Campos.
522

Devenir des apports solides du Rhône dans le Golfe du Lion : étude de la dynamique du panache turbide du Rhône en réponse aux forçages hydrométéorologiques / Fate of Rhône River sediment inputs to the Gulf of Lions : study of the Rhône River turbid plume dynamics in response to hydrometeorological forcings

Gangloff, Aurélien 08 December 2017 (has links)
Les contaminants, dissouts ou adsorbés sur les particules, sont principalement délivrés au milieu marin par les fleuves. La dynamique sédimentaire constitue alors un proxy de la dynamique de ces contaminants. Cette thèse s'inscrit dans le projet ANR AMORAD, et se focalise sur la dynamique du matériel particulaire délivré par le Rhône au Golfe du Lion (Méditerranée nord-occidentale), principal contributeur d'apports solides au Golfe (80 % des sédiments). Alors que des études antérieures ont permis de bien représenter les processus au niveau du fond, les processus régissant les comportements des matières en supension (MES), majoritairement rencontrées dans le panache turbide du Rhône, sont encore mal apréhendés. En vue de mieux décrire la dynamique de ces MES et d'améliorer les modèles hydrosédimentaires existants, l'objectif est de mieux caractériser ces particules. À cette fin, un vaste jeu de données issu de capteurs déployés in situ (données collectées pour 12 campagnes en mer, réalisées de 2011 à 2016) a été exploité, permettant d’obtenir une vision 2D verticale mais seulement ponctuelle (spatialement et temporellement). De façon complémentaire, une base de données d'images satellitaires (donnée couleur de l'eau du capteur MERIS-300m acquise entre 2002 et 2012), offrant une vue plus synoptique et long terme mais uniquement en surface, a été exploitée. Le jeu de données d'images satellitaire (plus de 800 images) a été traité de façon innovante par l'application d'un traitement semi-automatique permettant l'extraction de différentes métriques du panache turbide du Rhône (e.g. aire, limites d'extension, forme, centres géométriques, concentrations). La distribution spatiale et les caractéristiques physiques des MES telles que leur concentration dans l'eau, leur diamètre médian ou encore leur vitesse de chute ont été étudiées et estimées en fonction des différents forçages hydrométéorologiques actifs sur la zone d'étude (e.g. débit du Rhône, vents dominants). Un nouveau modèle hydrosédimentaire reposant sur le couplage du modèle hydrodynamique MARS-3D et du module sédimentaire multiclasse MIXSED a été configuré et les données in situ et satellitaires ont pu être mobilisées afin de contraindre la vitesse de chute des sédiments, paramètre clef de la modélisation de la dynamique hydrosédimentaire. / Contaminants, which can be dissolved in water or adsorbed on particles, are mainly delivered to the coastal environment by rivers. Thus, sediment dynamics reperesent a relevant proxy of contaminants dynamics. ThisPhD thesis is part of the ANR AMORAD project, of which one workpackage focuses on the fate of sediments in the coastal environment. This work focuses on the dynamics of Rhône River sediments in the Gulf of Lions (north-western mediterranean), this river delivering 80 % of the sediments of the Gulf. While previous studies over the area allowed a better understanding of physical processes at the water-sediment interface, processes driving suspended particulate matter (SPM) dynamics are still poorly understood. To better describe this SPM dynamics and improve hydrosedimentary models, the aim is to better characterize these particles. To this end, a large dataset collected from in situ deployed sensors (data collected for 12 field campaigns, conducted from 2011 to 2016) was analyzed to get a 2D vertical but ponctual view (both spatially and temporally). Complementary, a satellite images dataset (MERIS-300m ocean colour archive from 2002 to 2012) was built in order to get a long term and more synoptic view (but limited to surface).This dataset (more than 800 images) was originaly studied, applying a semi-empirical process to extract various Rhône River turbid plume metrics (e.g. area of extension, south-east-westernmost points, shape, centroids, SPM concentrations). Plume metrics and physical properties of SPM such as their concentration in water, their median diameter or their settling velocity were investigated regarding the different hydrometeorological forcings (e.g. Rhône River discharge, prevailing winds). A new hydrosedimentary model, based on the coupling of the 3D hydrodynamical model MARS-3D and the sedimentary module MIXSED, was set and ocean color and in situ data were used to constrain the settling velocity of particles, key parameter of hydrosedimentary modelling.
523

Uticaj suspendovanih čestica " PM2,5" iz vazduha životne sredine na mortalitet, kardiovaskularni i respiratorni morbiditet odraslog stanovništva Grada Novog Sada / Impact of ambient suspended particles “PM2,5” on mortality, cardiovascular and respiratory morbidity of adults in the city of Novi Sad

Dragić Nataša 27 February 2020 (has links)
<p>Kvalitet vazduha u urbanim sredinama predstavlja jedan od glavnih uzroka zdravstvenih problema. Prema podacima SZO u svetu se godi&scaron;nje usled zagađenja vazduha u urbanim sredinama dogodi preko 2,7 miliona smrtnih slučajeva. Procenjuje se da najbolji indikator za procenu veličine zdravstvenog rizika od zagađenja vazduha jeste koncentracija suspendovanih čestica PM2,5 u vazduhu životne sredine. Cilj: Proceniti uticaj suspendovanih čestica PM2,5 iz vazduha životne sredine na ukupan mortalitet, kardiovaskularni i respiratorni bolnički morbiditet odraslog stanovni&scaron;tva Grada Novog Sada. Takođe, cilj istraživanja je bio da se i utvrdi koncentracija i hemijski sastav suspendovanih čestica PM2,5 u vazduhu životne sredine na teritoriji Grada Novog Sada, na dnevnom i godi&scaron;njem nivou, uzimajući u obzir i uticaj meteorolo&scaron;kih parametara. Metod: Istraživanje je sprovedeno kao prospektivna studija vremenske serije podataka o kvalitetu vazduha, meteorolo&scaron;kim parametrima i zdravstvenim ishodima, u intervalima od najmanje 30 dana tokom sva četiri godi&scaron;nja doba 2017. godine. Uzorkovanje i određivanje koncentracije i hemijskog sastava čestica PM2,5 u skladu sa propisanim standardnim metodama, je obavljeno na mernim mestima u životnoj sredini Grada Novog Sada, koja reprezentuju uticaj saobraćaja i urbanog pozadinskog područja na zagađenje vazduha životne sredine. Primenjen je Lenschow pristup za kvantifikaciju veličine doprinosa saobraćaja porastu koncentracije suspendovanih čestica PM2,5 u vazduhu životne sredine. Podaci o meteorolo&scaron;kim parametrima (temperatura vazduha, relativna vlažnost vazduha i brzina vetra), su preuzeti od Republičkog hidrometeorolo&scaron;kog zavoda Srbije. Podaci o zdravstvenim ishodima (dnevni broj umrlih i hospitalizovanih zbog kardiovaskularnih i respiratornih bolesti), za stanovni&scaron;tvo starije od 18 godina, čije mesto stanovanja pripada teritoriji Grada Novog Sada, obezbeđeni su od strane Centra za informatiku i biostatistiku u zdravstvu Instituta za javno zdravlje Vojvodine. Za procenu uticaja nezavisnih promenljivih na zavisne (ukupan mortalitet / bolnički morbiditet) primenjen je generalizovani linearni model regresione analize za vremenske serije podataka (Poason). Rezultati: Prosečna godi&scaron;nja koncentracija suspendovanih čestica PM2,5 iz vazduha životne sredine na teritoriji Grada Novog Sada je iznosila 30,27 &mu;g/m3, a srednje dnevne koncentracije 8-79&nbsp; g/m3. Približno 30% varijabilnosti srednjih dnevnih koncentracije suspendovanih čestica PM2,5 se može objasniti lokalnim meteorolo&scaron;kim uslovima. Hemijski sastav čestica na području Grada Novog Sada u najvećem procentu čini ekvivalent karbonatne frakcije čestica, zatim sekundarni neorganski aerosol i rastvorljiva organska frakcija, dok su joni rastvorljivi u vodi (kalcijum, hloridi, natrijum, kalijum i magnezijum) zastupljeni u najmanjem procentu. Prisutni izvori zagađenja vazduha životne sredine na području Grada Novog Sada su procesi sagorevanja fosilnih goriva i biomase, saobraćaj, mineralna (zemlji&scaron;na) pra&scaron;ina i sekundarno zagađenje regionalnog porekla. Doprinos saobraćaja porastu prosečne godi&scaron;nje koncentracije suspendovanih čestica PM2,5 je iznosio 40%. Masena koncentracija čestica PM2,5, kao i hemijski sastav čestica (ekvivalent karbonatne frakcije, rastvorljiva organska frakcija, joni kalijuma i kalcijuma) doprinose umiranju i oboljevanju odraslog stanovni&scaron;tva Grada Novog Sada. Na uticaj masene koncentracije i hemijskog sastava čestica PM2,5 najosetljivije su žene i stanovni&scaron;tvo starosti &ge; 65 godina, kao i mu&scaron;karci u pogledu uticaja ekvivalenta karbonatne frakcije čestica PM2,5. Zaključak: Dobijeni rezultati po prvi put opisuju zdravstveni uticaj masene koncentracije i hemijskog sastava čestica PM2,5 na području Grada Novog Sada, odnosno kvantifikuju rizik za ukupan mortalilteta i kardiovaskualrni i respiratorni morbiditet. Razumevanje uticaja suspendovanih čestica PM2,5 na oboljevanje i umiranje stanovni&scaron;tva, stratifikovanih prema starosnoj i polnoj strukturi, uz identifikaciju mogućih izvora zađenja vazduha na području Grada Novog Sada, predstavlja osnovu za razvoj javnozdravstvene politike u cilju unapređenja zdravlja stanovni&scaron;tva Grada Novog Sada.</p> / <p>Urban ambient air pollution is one of the leading causes of health problems. According to WHO data, over 2.7 million deaths occur in urban areas annually due to urban air pollution. Particulate matter PM2.5 is estimated to be the best indicator for assessing the magnitude of the health risk induces by ambient air pollution. Aim: To assess the impact of PM2.5 on total mortality, cardiovascular and respiratory hospital morbidity of the adult population of the City of Novi Sad. Also, the aim of the study was to determine the concentration and chemical composition of ambient PM 2.5 particles in the territory of the City of Novi Sad, on daily and annual bases, taking into account the impact of meteorological parameters. Method: The study was conducted as a prospective, a time series study of of data on air quality, meteorological parameters and health outcomes, at intervals of at least 30 days during all four seasons of 2017. Sampling and determination of the mass concentration and chemical composition of PM2.5 particles in accordance with the prescribed standard methods, it was performed at sampling stations in the City of Novi Sad, representing the impact of traffic and urban background impact on environmental air pollution. A Lenschow approach was used to quantify the magnitude of traffic contribution to the increase of ambient PM2.5 mass concentration. Meteorological data (air temperature, relative humidity and wind velocity) were taken from the Republic Hydrometeorological Institute of Serbia. Data on health outcomes (daily number of deaths and hospitalizations due to cardiovascular and respiratory diseases) for the population older than 18, residing within the territory of the City of Novi Sad, have been provided by the Centre for Informatics and Biostatistics, Institute of Public Health of Vojvodina. To evaluate the impact of independent variables on dependent (total mortality/hospital morbidity), a generalized linear regression model for time series data (Poisson) was applied. Results: The average annual mass concentration of PM2.5 in the territory of the City of Novi Sad was 30.27&mu;g/m3, while mean daily concentrations were 8- 79&mu;g/m3. Approximately 30% of the variability in mean daily concentrations of PM2.5 particles can be explained with local meteorological conditions. The chemical composition of PM2.5 in the area of Novi Sad is to the a great extent the equivalent of the carbonate fraction of the particles, then the secondary inorganic aerosol and the soluble organic fraction, while the water-soluble ions (calcium, chlorides, sodium, potassium and magnesium) are present in the lowest percentage. The sources of ambient air pollution in the area of the City of Novi Sad were the combustion of fossil fuels and biomass, traffic, mineral (soil dust) and secondary pollution of regional origin. Contribution of traffic to the increase of the average annual mass concentrations of PM2.5 particles was 40%. PM2.5 particle mass concentration, as well as the chemical composition of the particles (carbonate fraction equivalent, soluble organic fraction, potassium and calcium ions) contribute to the deaths and diseases of the adult population of the City of Novi Sad. Women and the population aged &ge;65, were more susceptible to mass concentration and chemical composition of PM2.5 related deaths and diseases, as well as men according to the impact of the equivalents of carbonate fractions of PM2.5. Conclusion: The results obtained show for the first time the health effects of mass concentration and chemical composition of PM2.5 particles in the City of Novi Sad, i.e. they quantify the risk for total mortality and cardiovascular and respiratory morbidity. Understanding the impact of suspended particles PM2.5 on population mortality and morbidity, stratified by age and sex structure, along with identifying of possible air pollution sources is the basis for the development of public health policies aimed at improving the population health in the City of Novi Sad.</p>
524

Outdoor air pollution, green space, and cancer incidence in Saxony: a semi-individual cohort study

Datzmann, Thomas, Markevych, Ianna, Trautmann, Freya, Heinrich, Joachim, Schmitt, Jochen, Tesch, Falko 15 June 2018 (has links)
Background There are a few epidemiological studies that (1) link increased ambient air pollution (AP) with an increase in lung cancer incidence rates and (2) investigate whether residing in green spaces could be protective against cancer. However, it is completely unclear whether other forms of cancer are also affected by AP and if residential green spaces could lower cancer incidence rates in general. Therefore, the objective was to estimate whether AP and green space are associated with several cancer types. Methods The analysis was based on routine health care data from around 1.9 million people from Saxony who were free of cancer in 2008 and 2009. Incident cancer cases (2010–2014) of mouth and throat, skin (non-melanoma skin cancer - NMSC), prostate, breast, and colorectum were defined as: (1) one inpatient diagnosis, or (2) two outpatient diagnoses in two different quarters within one year and a specific treatment or death within two quarters after the diagnosis. Exposures, derived from freely available 3rd party data, included particulate matter with aerodynamic diameter of less than 10 μm (PM10) and nitrogen dioxide (N02) as well as green space (Normalized Difference Vegetation Index - NDVI). Associations between air pollutants, green space, and cancer incidence were assessed by multilevel Poisson models. Age, sex, physician contacts, short- and long-term unemployment, population density, and having an alcohol-related disorder were considered as potential confounders. Results Three thousand one hundred seven people developed mouth and throat cancer, 33,178 NMSC, 9611 prostate cancer, 9577 breast cancer, and 11,975 colorectal cancer during the follow-up period (2010–2014). An increase in PM10 of 10 μg/m3 was associated with a 53% increase in relative risk (RR) of mouth and throat cancer and a 52% increase in RR of NMSC. Prostate and breast cancer were modestly associated with PM10 with an increase in RR of 23 and 19%, respectively. The associations with N02 were in the same direction as PM10 but the effect estimates were much lower (7–24%). A 10% increase in NDVI was most protective of mouth and throat cancer (− 11% RR) and of NMSC (− 16% RR). Colorectal cancer was not affected by any of the exposures. Conclusions In addition to the studies carried out so far, this study was able to provide evidence that higher ambient AP levels increase the risk of mouth and throat cancer as well as of NMSC and that a higher residential green space level might have a protective effect for NMSC in areas with low to moderate UV intensity. Nevertheless, we cannot rule out residual confounding by socioeconomic or smoking status.
525

Health Effects of Occupational Exposure of Wildland Firefighters to Smoke from Biomass Burning

Wu, Chieh-Ming January 2020 (has links)
No description available.
526

Sledování kvality ovzduší v ostravské průmyslové aglomeraci / Monitoring of air quality in the Ostrava industrial agglomeration

Krejčí, Blanka January 2020 (has links)
Presented thesis deals with the evaluation of air quality in Ostrava industrial area, especially with regard to highly concentrated suspended particles and sorbed on them toxic polyaromatic hydrocarbons. Their above-limit concentrations are the main cause of negative effects on the health of humans and other organisms in one of the most outstanding European "hot- spot"regions, in the industrial agglomeration of Ostrava. The first part of the work is devoted to the evaluation of pollutant concentrations and contributions of identified types of air pollution sources in the wider influence area of a large industrial source in the Ostrava region. It was confirmed the concentrations of all pollutants show very significant inter-seasonal differences between the warm and cold parts of the year. The measured concentrations of PAHs in the cold season were 3 to 5 times higher than in the warm season. Less pronounced differences in concentration levels were seen between day and night samples. The air-pollution load was highest at the Radvanice site, compared to Vratimov and the background area of Poruba. The pollution caused by suspended particles originating from the emissions of the industrial complex in the annual scale contributes significantly to the resulting air quality image on the site, but is not an exclusive source. Other identified sources of the contributions to the PM2.5 concentrations are regional sources and operating seasonally sources (local heating). The second part of the thesis is an assessment of the character and regularities of air mass transmission in the ground-level layer of the troposphere in the Czech-Polish border area, as regional and long-range pollution transport plays a significant role, manifested in the resulting reduced air quality. The contribution of cross-border pollution sources is an important component of often alarming concentrations of atmospheric pollutants, especially during winter smog situations. It was shown within the northeast steady flow is dominated by the shift of higher concentrations of suspended particles from Poland to the Czech Republic. On the other hand, with the opposite prevailing direction of steady flow, particle concentrations on the Polish side of the territory are not increasing dramatically. At least half the year there are situations with variable wind direction, or low flow velocities during which the entire area on both sides of the border there are maximum concentrations of particles, including sorbed polyaromatics with the most serious health effects.
527

Výzkum progresivních metod snižování obsahu škodlivých látek ve výfukových plynech vznětových motorů / Research of Progressive Methods for Reduction of Emissions in CI Engine Exhaust Gasses

Franz, Rudolf January 2020 (has links)
The scope of this dissertation work is a description of modern methods of reducing exhaust emission in diesel engines. The fundamental part is the application of these methods for diesel engines for off-road use that means for engines that are used in tractors and road machines. The mentioned evidence for the practical utility of the results of this dissertation thesis in practice and their verification on the actual engine are given in the conclusion.
528

Pevnostně deformační analýza uchycení filtru pevných částic na traktoru / Stress-strain Analysis of Diesel Particulate Filter Support on Tractor

Ježek, Přemysl January 2012 (has links)
The subject of this thesis is to carry out stress-strain analysis of diesel particulate filter support on tractor. So it describes sequence of steps for the analysis model, such as geometry description, mesh generation, applied forces definition and others. Result of the analysis is assessed in terms of strength and improvement was proposed.
529

Zlepšování parametrů prototypu mycí samosběrací nástavby / Improving the parameters of the prototype of self-loading water sweeper superstructure

Vraspír, Kamil January 2016 (has links)
This thesis explores development stages of a Self-loading water sweeper superstructure prototype. The theoretical part describes thoroughfares in terms of pollution, various types of cleaning machines currently in use and a detailed description of the FMEA method, which was used for identification of potential failure modes and risk mitigation. Stages of measurement and superstructure parameter improvement are proposed, executed and described in the practical part. In these stages, creation of model documentation, verification of functionality and stage of analysis FMEA are included. Furthermore, this section describes the results of tests devised to validate key superstructure parameters. The result of the work is a functional Self-loading water sweeper superstructure prototype, confirmation of key superstructure functional parameters and a draft of a series of improvement measures aimed at eliminating potential risks associated with operation of the superstructure.
530

Flux sédimentaire en estuaire de Seine : quantification et variabilité multi-échelle sur la base de mesure de turbidité (réseau SYNAPSES) / Sediment fluxes in the Seine estuary : quantification and variability based on turbidity measurements (SYNAPSES monitoring network)

Druine, Flavie 26 June 2018 (has links)
La dynamique des Matières en Suspension (MES) dans les estuaires macrotidaux est fortement variable à la fois spatialement (du compartiment fluvial à l'embouchure de l'estuaire) et temporellement (de la seconde à plusieurs années), mais reste primordiale pour comprendre et quantifier la dynamique sédimentaire des environnements estuariens. Avec le développement croissant des réseaux de mesures haute-fréquence à l'échelle internationale, l'objectif principal de cette étude est de qualifier et de valoriser les mesures de turbidité acquises par un réseau de mesures haute fréquence (réseau SYNAPSES) implanté d'amont en aval sur l'estuaire de la Seine (France) à la fois (i) en matière de suivi de la dynamique des MES du compartiment fluvial au bouchon vaseux et (ii) en matière d'estimation des flux de MES sur différentes échelles spatio-temporelles de l'estuaire de la Seine. Les données acquises à partir du réseau SYNAPSES et des campagnes in situ (81 journées de 12 h - OBS-3+/YSI/LISST 100X-C/ADCP 600 kHz) sur quatre stations réparties de l'estuaire fluvial à la zone du bouchon vaseux, constituent un set de données extrêmement riche et unique sur les domaines estuariens. La variabilité des relations, établies entre les mesures de turbidité [NTU] et les mesures de concentrations en MES [g.L-1] sur chacune des campagnes de l'échelle tidale à annuelle, met en évidence l'effet (i) de la technologie interne du capteur et (ii) de la variabilité des propriétés optiques inhérentes des particules (diamètre médian D50), densité sèche rhô et efficacité de diffusion Qc) sur la sensibilité des différents capteurs optiques. L'analyse conjointe des données in situ et des données SYNAPSES a permis de calibrer les mesures de turbidité en concentration massique, avec une relation validée sur le cycle annuel, spécifique à chacune des stations et des incertitudes minimisées. Après une étude de la représentativité des stations du réseau vis-à-vis de la section, les flux instantanés de MES sont estimés (i) à partir des données de concentrations en MES et de débits acquis par l'ADCP sur l'intégralité de la section et (ii) à partir des concentrations ponctuelles en MES du réseau SYNAPSES couplées au modèle hydrodynamique MARS-3D. Les comparaisons des flux de MES in situ par rapport à ceux estimés par la combinaison SYNAPSES/MARS-3D permettent de proposer un coefficient spécifique à chacune des stations du réseau SYNAPSES, dans le but d'ajuster les flux instantanés de MES estimés, avec leurs incertitudes, à partir du réseau SYNAPSES à la réalité in situ. Les outils et les démarches développés dans la thèse sur l'estuaire de la Seine pauvent être appliqués à d'autres estuaires macrotidaux pour estimer les flux sédimentaires. / The dynamics of Suspended Particulate Matter (SPM) in macrotidal estuaries is highly variable both spatially (from the fluvial compartment to the estuary mouth) and temporally (from the second to several years), but it is essential to understand and quantify the sedimentary dynamics of estuarine environments. With the development of high-frequency measurement networks around the world, the main objective of this study is to qualify the turbidity measurements acquired by a high-frequency measurement network (SYNAPSES network) located on the Seine estuary (i) in terms of monitoring the SPM dynamics from the fluvial compartment to the turbidity maximal zone (TMZ) and (ii) in terms of estimation of the SPM fluxes on different spatio-temporal scales of the Seine estuary. Data acquired from the SYNAPSES network and complementary in situ campaigns (81 days of 12 h - OBS-3+/YSI/LISST 100X-C / ADCP 600 kHz) on four stations from the fluvial estuary of the Seine Estuary to the turbidity maximal zone, are an extremely rich and unique dataset on estuarine environments. The variability in the relationship between turbidity measurements [NTU] and SPM concentration measurements [g.L-1] on each campaign, reveals the effect of (i) the internal sensor technology and (ii) the variability of the particle inherent optical properties (median diameter D50, dry density rho and scattering efficiency Qc) on the sensitivity of different optical sensors. The analysis of the in situ and the SYNAPSES data allowed to calibrate the turbidity measurements in mass concentration, with a validated relationship on the annual cycle, specific to each of the stations and reduced uncertainties. After a study of the SYNAPSES station representativeness across the section, the instantaneous fluxes of SPM are estimated (i) from the SPM concentration and liquid flow data acquired by the ADCP on the global section and (ii) from the SPM concentrations of the SYNAPSES network coupled to the hydrodynamic model MARS-3D (estimation of the liquid flow). Comparisons of SPM fluxes in situ to those estimated by the combination SYNAPSES/MARS-3D allow to propose a specific coefficient for each of the SYNAPSES network stations, xith the aim of adjusting the SPM instantaneous fluxes estimated from the SYNAPSES network to the in situ reality, with reasonable uncertainties. the tools and approaches developed in the PhD thesis on the Seine estuary can be applied to other macrotidal estuaries to estimate sedimentary fluxes.

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