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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.
41

Dados MODIS e Landsat-8 para análise da água da Lagoa dos Patos, RS / MODIS and Landsat-8 for water analysis of the Patos Lagoon, Brazil

Andrade, Alice César Fassoni de January 2016 (has links)
Imagens adquiridas por sensores orbitais possibilitam observações da Terra e auxiliam estudos de grande áreas. Este trabalho utilizou imagens orbitais para analisar os componentes que modificam as características óticas da água na Lagoa dos Patos, localizada no sul do Brasil. A partir de imagens multiespectrais dos sensores MODIS/Terra e OLI/Landsat-8, foi possível avaliar a variação espaço-temporal de sólidos em suspensão (SS) e estimar alguns parâmetros de qualidade da água na Lagoa dos Patos. Na primeira etapa desse trabalho, o padrão anual e espacial de SS na laguna foi determinado com base em uma série de 15 anos do produto MOD09Q1 (reflectância na faixa do vermelho do sensor MODIS). Foi observado que a reflectância possui um padrão sazonal com aumento do outono até o final da primavera, e que no corpo lagunar e no estuário a reflectância varia ao longo do ano. Interpretações da variação da reflectância, relacionadas a descarga fluvial e a ação dos ventos, foram apresentadas. Na segunda etapa desse trabalho, o modelo linear de mistura espectral (MLME) foi aplicado em uma imagem do sensor OLI para separar águas espectralmente distintas do estuário da Lagoa dos Patos. A partir das imagens frações, geradas pelo MLME, e das bandas do sensor OLI e TIRS modelos empíricos foram desenvolvidos para estimar alguns parâmetros de qualidade da água. Os modelos obtidos foram capazes de estimar a concentração de clorofila-a (R2 = 0,82) e de sólidos em suspensão (R2 = 0,62), a turbidez (R2 = 0,67) e a profundidade do disco Secchi (R2 = 0,64). Conclui-se que o MLME e os dados do satélite Landsat-8 apresentam grande potencial para estimativa de parâmetros da água por imagens orbitais. / Images acquired by orbital sensors enable observations of the Earth and assist studies of large areas. This work used orbital images to analyze the components that modify the optical characteristics of the water of Lagoa dos Patos, located in the southern region of Brazil. By using multispectral images from MODIS/Terra and OLI/Landsat-8 sensors it was possible to evaluate the spatio-temporal variation of suspended solids (SS) and estimate some parameters of water quality. In the first stage of this work, the annual and spatial pattern of SS were estimated based on a series of 15 years of MOD09Q1 product (reflectance in the red channel of MODIS sensor). It was observed that the reflectance has a seasonal pattern with increase in the autumn until the late spring, and that in the lagoon body and estuary the reflectance varies throughout the year. Interpretations of the spatio-temporal variation of reflectance related to river discharge and the action of the winds were presented. In second stage of this study, the Linear Spectral Mixing Model (LSMM) was applied to an image of the OLI sensor to separate spectrally distinct waters of Lagoa dos Patos estuary. From the fraction images generated by LSMM and the bands of OLI and TIRS sensors, empirical models were developed to estimate some parameters of water quality. The obtained models were able to estimate the concentration of chlorophyll (R2 = 81,56) and the suspended solids (R2 = 61,57), turbidity (R2= 67,14) and Secchi disk depth (R2 = 64,29). Combination of LSMM and the Landsat- 8 satellite have shown great potential for water parameters estimation from orbital images.
42

Dados MODIS e Landsat-8 para análise da água da Lagoa dos Patos, RS / MODIS and Landsat-8 for water analysis of the Patos Lagoon, Brazil

Andrade, Alice César Fassoni de January 2016 (has links)
Imagens adquiridas por sensores orbitais possibilitam observações da Terra e auxiliam estudos de grande áreas. Este trabalho utilizou imagens orbitais para analisar os componentes que modificam as características óticas da água na Lagoa dos Patos, localizada no sul do Brasil. A partir de imagens multiespectrais dos sensores MODIS/Terra e OLI/Landsat-8, foi possível avaliar a variação espaço-temporal de sólidos em suspensão (SS) e estimar alguns parâmetros de qualidade da água na Lagoa dos Patos. Na primeira etapa desse trabalho, o padrão anual e espacial de SS na laguna foi determinado com base em uma série de 15 anos do produto MOD09Q1 (reflectância na faixa do vermelho do sensor MODIS). Foi observado que a reflectância possui um padrão sazonal com aumento do outono até o final da primavera, e que no corpo lagunar e no estuário a reflectância varia ao longo do ano. Interpretações da variação da reflectância, relacionadas a descarga fluvial e a ação dos ventos, foram apresentadas. Na segunda etapa desse trabalho, o modelo linear de mistura espectral (MLME) foi aplicado em uma imagem do sensor OLI para separar águas espectralmente distintas do estuário da Lagoa dos Patos. A partir das imagens frações, geradas pelo MLME, e das bandas do sensor OLI e TIRS modelos empíricos foram desenvolvidos para estimar alguns parâmetros de qualidade da água. Os modelos obtidos foram capazes de estimar a concentração de clorofila-a (R2 = 0,82) e de sólidos em suspensão (R2 = 0,62), a turbidez (R2 = 0,67) e a profundidade do disco Secchi (R2 = 0,64). Conclui-se que o MLME e os dados do satélite Landsat-8 apresentam grande potencial para estimativa de parâmetros da água por imagens orbitais. / Images acquired by orbital sensors enable observations of the Earth and assist studies of large areas. This work used orbital images to analyze the components that modify the optical characteristics of the water of Lagoa dos Patos, located in the southern region of Brazil. By using multispectral images from MODIS/Terra and OLI/Landsat-8 sensors it was possible to evaluate the spatio-temporal variation of suspended solids (SS) and estimate some parameters of water quality. In the first stage of this work, the annual and spatial pattern of SS were estimated based on a series of 15 years of MOD09Q1 product (reflectance in the red channel of MODIS sensor). It was observed that the reflectance has a seasonal pattern with increase in the autumn until the late spring, and that in the lagoon body and estuary the reflectance varies throughout the year. Interpretations of the spatio-temporal variation of reflectance related to river discharge and the action of the winds were presented. In second stage of this study, the Linear Spectral Mixing Model (LSMM) was applied to an image of the OLI sensor to separate spectrally distinct waters of Lagoa dos Patos estuary. From the fraction images generated by LSMM and the bands of OLI and TIRS sensors, empirical models were developed to estimate some parameters of water quality. The obtained models were able to estimate the concentration of chlorophyll (R2 = 81,56) and the suspended solids (R2 = 61,57), turbidity (R2= 67,14) and Secchi disk depth (R2 = 64,29). Combination of LSMM and the Landsat- 8 satellite have shown great potential for water parameters estimation from orbital images.
43

Identification of processes leading to long-term wastewater purification in northern treatment wetlands

Karjalainen, S. M. (Satu Maaria) 16 August 2016 (has links)
Abstract Treatment wetlands (TW) constructed on natural wetlands potentially perform efficient purification of wastewater, but the longevity of TWs at northern latitudes is not well known. This thesis examined processes affecting nutrient and suspended solids (SS) retention in TWs during their lifetime. In total, 15 TWs were studied using water and peat quality and gas flux data for different TW life lengths, the longest period being 18 years. The TWs commonly retained nutrients and suspended solids efficiently, even after 18 years of wastewater loading. For nitrogen (N) removal, sedimentation, nitrification-denitrification and plant uptake were efficient processes in the wetlands studied. However, emissions of nitrous oxide (N2O) from TWs are not a major contributor to climate change due to the small total surface area of TWs. The significance of anaerobic ammonium oxidation (anammox) and other newly discovered nitrogen processes in TWs remains to be clarified. Phosphorus (P) adsorption capacity in TWs remained efficient over a 12-year study period, the process being continuous when surfaces for adsorption were available or freed up through alternating absorption/desorption/adsorption. Phosphorus accumulation by peat accretion was low, but has not been well assessed in northern TWs receiving nutrient-rich waters. Iron (Fe) and aluminium (Al) in peat extraction runoff and purified wastewater from sewage treatment plants were of great importance for precipitation of P in TWs. Filtration and sedimentation of organic humic substances with Fe- or Al-bound P were other probable P retention pathways. In peat extraction runoff, Fe was more significant than Al for P retention, but Fe-bound P is susceptible to desorption in anaerobic environments, whereas Al-bound P is more strongly retained. Suspended solids were generally retained well, although there was great variation in percentage retention in individual TWs in different years and different seasons. Changes in discharge affected SS transportation and retention. SS were retained by sedimentation, the rate of which was affected by particle size. It is plausible that smaller particles from old peat extraction areas where the extracted peat has a high humification degree erode more easily than poorly humified particles in surface peat. Weakened SS retention may also have been caused by development of preferential flow areas (PFA) in TWs, changes in sediment delivery characteristics and sampling involving too few samples to show SS transportation sufficiently accurately for estimating SS retention. Thus TWs are potentially ideal for purification of wastewater and can have high purification efficiency even after long-term use in northern regions. They are also more widely applicable as long as their limitations are understood. / Tiivistelmä Kosteikkopuhdistamot, jotka on rakennettu luonnonkosteikoille, voivat tehokkaasti vähentää erilaisten maankäyttömuotojen ja pistekuormituslähteiden vesistökuormitusta. Niiden käyttöikää pohjoisilla alueilla ei kuitenkaan tunneta hyvin. Tässä väitöskirjassa tarkastellaan kosteikkopuhdistamoissa tapahtuvia biologisia, kemiallisia ja fysikaalisia prosesseja, joilla on vaikutusta ravinteiden ja kiintoaineen pidättymiseen. Yhteensä 15 eri-ikäisen kosteikkopuhdistamon toimintaa tutkittiin veden ja turpeen laadun sekä kasvihuonekaasumittausten avulla. Näistä vanhinta kosteikkoa oli tutkimusta tehdessä käytetty 18 vuotta turvetuotannon valumavesien puhdistukseen. Tyypillisesti kosteikkopuhdistamot pidättivät ravinteita ja kiintoaineita tehokkaasti jopa 18 vuoden käytön jälkeen. Typenpoistossa sedimentaatio, nitrifikaatio-denitrifikaatio ja kasvien ravinteidenotto olivat tutkituilla kosteikoilla tehokkaita prosesseja. Kosteikkopuhdistamoiden typpioksiduulipäästöt (N2O) ilmaan eivät kuitenkaan ole merkittäviä ilmastonmuutoksen aiheuttajia, koska tällaisten kosteikkopuhdistamoiden kokonaispinta-ala on pieni. Anammox- (anaerobic ammonium oxidation) ja muiden viimeaikoina muissa tutkimuksissa havaittujen typpiprosessien merkitys kosteikoilla tulisi vielä selvittää. Fosforin adsorptiokyky kosteikkopuhdistamoilla pysyi tehokkaana 12 vuoden tutkimusjaksolla, koska niissä adsorptiopintoja oli joko vapaana tai niitä vapautui absorptio- ja desorptioprosessien seurauksena. Kosteikkopuhdistamolla fosforin kertyminen turpeen muodostuksessa arvioitiin vähäiseksi, tosin kertymistä ei ole tarkkaan määritetty pohjoisilla kosteikkopuhdistamoilla, joihin tulee ravinteikasta vettä. Turvetuotannon valumavesissä ja jätevedenpuhdistamoilta tulleissa vesissä orgaanisten humusaineiden rautaan ja alumiiniin sitoutuneen fosforin suodattuminen ja sedimentoituminen olivat muita todennäköisiä fosforin pidättymismekanismeja kosteikoilla. Turvetuotannon valumavesissä rauta oli alumiinia merkittävämpi tekijä fosforin pidättymisessä. Rautaan sitoutunut fosfori on kuitenkin altis desorptiolle hapettomissa olosuhteissa, kun taas alumiiniin sitoutunut fosfori pidättyy pysyvämmin. Kiintoaines pidättyi kosteikkopuhdistamoissa yleensä hyvin, vaikka pidättyneen aineen osuudessa kokonaiskuormituksesta oli suurta vaihtelua yksittäisissä kosteikkopuhdistamoissa eri vuosina ja eri vuodenaikoina. Muutokset virtaamissa vaikuttivat kiintoaineksen kulkeutumiseen ja pidättymiseen. Kiintoaines pidättyy sedimentaatiossa, jonka suuruuteen vaikuttaa kiintoaineen partikkelikoko. On todennäköistä, että vanhojen turvetuotantoalueiden korkean humusasteen pienikokoiset turvepartikkelit erodoituvat helpommin kuin pintaturpeen vähemmän hajonneet partikkelit. Heikentynyt kiintoaineen pidättyminen saattaa aiheutua myös kosteikkopuhdistamoiden oikovirtauksien kehittymisestä, muutoksista sedimentin kulkeutumistavoissa ja liian harvoista näytteenotoista, jolloin ei pystytä riittävän tarkasti arvioimaan kiintoaineksen pidättymistä. Kosteikkopuhdistamot voivat olla ideaalisia jätevesien puhdistamiseen ja ovat osoittaneet hyvää puhdistustehokkuutta myös pitkäaikaisessa käytössä pohjoisissa olosuhteissa. Siten ne ovat laajasti sovellettavissa, kunhan niiden käyttömahdollisuuksien rajoitteet on otettu huomioon.
44

Turbiditet som proxy för slamhalt : Markfaktorers påverkan på korrelationen / Turbidity as a Proxy for Suspended Solids : Landscape Factors Influence on the Correlation

Carlsson, Karin January 2022 (has links)
Vatten är en livsviktig resurs därför behöver kvalitén övervakas. Slamhalt i vatten är viktigt eftersom det kan föra med sig gifter och näringsämnen, men även grumlar vattnet vilket kan påverka livsmiljön för vattenlevande organismer. Slamhalt varierar över tid på grund av olika processer som transporterar material till vattendrag. För att mäta slamhalten har man historiskt tagit vattenprover i fält. Det är tidsödande och görs sällan vilket leder till att man lätt missar toppar och dalar i flödet.  Turbiditet är möjligt att mäta in situ och innebär att vattnets ljusgenomsläpplighet mäts. Det kan mätas med täta intervall vilket ger detaljerad information om förändringar i vattendragen. Korrelationen mellan turbiditet och slamhalt har undersökts flera gånger men eftersom mätningar reagerar på partiklars storlek och form behöver man utvärdera sambandet för varje enskilt vattendrag.  2017 gjordes en studie för Sveriges lantbruksuniversitet där Hoang (2017) använde multivariabel statistik för att undersöka turbiditet korrelerat med fosfor samt jordarters och markanvändnings påverkan på relationen i svenska vatten.  Sedan dess har markdata uppdaterats vilket gör det aktuellt att undersöka korrelationen mellan slamhalt och turbiditet. Genom linjär regression visades ett tydligt samband mellan turbiditet och slamhalt för många avrinningsområden. De högsta korrelationerna syntes för områden med hög fördelning av åkermark och lerhalt. / Water is a vital resource for life, that is why water quality is monitored. Suspended solids in water are important because it transports pollutants and nutrients, it also dims the water which can affect the environment for water living organisms. Suspended solids change over time due to different processes that transport materials to waterbodies. Historically, suspended solids have been measured by taking samples in the field. That takes a lot of time and fluctuations are lost because of dispersed measuring periods.  Turbidity can be measured in-situ and quantifies the light attenuation of the water. It can be measured with tight intervals which results in detailed information about changes in the waterbody. The correlation between suspended solids and turbidity has been studied several times, however, a turbidity sensor reacts to particle size and form which means that the correlation needs to be investigated for every individual waterbody.  2017 a study at the Swedish university of agriculture was done where Hoang (2017) used multivariate statistics to study turbidity correlated with phosphorus, as well as soil classes and land use factors influence on the relationship in Swedish waters. Since then, new data for soil and land use have been updated which makes it relevant to evaluate the correlation between suspended solids and turbidity. Through linear regression a clear correlation was shown for many catchments. The highest correlations were found in areas with high rates of agriculture and clay rich soils.
45

Sorbentų naudojimo paviršinėms nuotekoms valyti tyrimai ir analizė / Research and analysis of sorbent usage for storm water run-off purification

Levickaitė, Giedrė 20 June 2011 (has links)
Didžiausiais paviršinių nuotekų teršalais laikomi naftos produktai ir skendinčiosios medžiagos. Pastarąsias galima nesunkiai pašalinti taikant tradicinius paviršinių nuotekų valymo metodus, tokius kaip nusodinimas, o naftos produktų šalinimui reikalingas antrinis nuotekų valymas. Vienas efektyviausių NP šalinimo iš nuotekų būdas yra filtravimas pro sorbuojančiosios medžiagos filtrą. Nors šiuo būdu valant nuotekas galima pasiekti didelio teršalų šalinimo efektyvumo, praktiškai dažnai susiduriama su problema, kai į eksploatuojamuosius valymo įrenginius nuotekos atiteka dideliais greičiais ir teršalai nėra iki galo pašalinami. Todėl šiame darbe buvo atliktas trijų skirtingų sintetinių sorbentų („Fibroil, „Duck“, „Reo-dry“) efektyvumo šalinti iš paviršinių nuotekų naftos produktus ekstremaliomis sąlygomis (esant dideliems greičiams) eksperimentinis tyrimas. Atlikus bandymus su dirbtinėmis ir realiomis paviršinėmis nuotekomis laboratoriniame stende, nustatyta, kad visų trijų sorbentų efektyvumas šalinti NP yra panašus ir skendinčiosios medžiagos bei nuotekų drumstumas neturi įtakos NP šalinimo efektyvumui. Tačiau „Fibroil“ sorbentą naudojant kaip filtro užpildą, 30 m/h greitį galima išlaikyti gerokai ilgiau nei su sorbentais „Duck“ ir „Reo-dry“ ir šį sorbentą naudoti ekonomiškiausia. Darbą sudaro 8 dalys: įvadas, darbo aktualumo aprašymas, literatūros apžvalga, tiriamojo darbo metodikos aprašymas, eksperimeto rezultatai, rekomendacijos ir išvados bei literatūros sąrašas. Darbo... [toliau žr. visą tekstą] / Suspended solids and oil products are considered as the most important pollutants in the storm water. As suspended solids can be easily retained from storm water by simple sedimentation, for oil products it is usually needed to have a secondary treatment: filtration through sorbents media. Although storm water filtration through a sorbent filter gives high treatment efficiency, it is usually impossible to ensure the right speed of storm water coming to the treatment facilities (it is usually too high to ensure an efficient sorption). For this reason the research and analysis of three different synthetic sorbents („Fibroil“, „Duck“, „Reo-dry“) were performed with artificial and real storm water in the laboratory under extreme conditions (filtration speed 30 m/h). According to the results of the experiment, all three sorbents have similar treatment efficiency and suspended solids and turbidity has no impact on oil products removal efficiency. But it is more efficient to use “Fibroil” and it is suitable for filtration under 30 m/h speed much longer than sorbents “Duck” and “Reo-dry”. Structure: introduction, relevance, methodology, results of the experiment, recomedations conclusions and references. Thesis consist of: 55 p. text without appendixes, 21 pictures, 8 tables, 39 bibliographical entries.
46

Espécies químicas inorgânicas (Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb e Sn) no sedimento e nos sólidos em suspensão do rio Corumbataí, SP / Inorganic chemical species (Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb e Sn) in sediment and suspended matter in the Corumbataí River, SP.

Zambetta, Paula Munhoz Antunes 15 September 2006 (has links)
Os teores totais e trocáveis de alumínio, arsênio, cádmio, cobre, ferro, manganês, mercúrio, níquel, chumbo e estrôncio, foram determinados em amostras de sedimento do rio Corumbataí. As leituras para quantificação dos elementos foram feitas por espectrometria de emissão atômica com plasma acoplado indutivamente (ICP-AES), análise por ativação neutrônica (AAN) e espectrometria de fluorescência atômica (AFS). As amostras para determinação dos teores totais de metais, quantificados por ICP-AES e AFS foram digeridas em bombas de Teflon em meio de água régia. Para quantificação de metais trocáveis utilizou-se extração a frio com HCl 1,0 M. O As foi quantificado por AFS através de geração de hidretos. Para comparação de resultados, Fe, Cr e As foram também analisados por AAN, método em que a amostra foi irradiada com fluxo de nêutrons térmicos de 1012n cm-2 s-1 e a determinação do elemento feita em espectrômetro de raios gama por meio das radiações emitidas pelos radionuclídeos formados. As amostras de sedimento foram coletadas em sete pontos ao longo do Rio Corumbataí, em março, agosto e novembro de 2004 e fevereiro de 2005. Coletas de águas superficiais para a determinação de variáveis físicas, químicas e biológicas, as quais compõem o Índice de Qualidade de Água (IQA), preconizado pela CETESB, foram realizadas concomitantemente. No período de cheia, ou seja, novembro de 2004 e fevereiro de 2005 foram obtidas amostras de sólidos em suspensão, que passaram pelos mesmos procedimentos descritos para sedimento. As amostras foram caracterizadas quanto à granulometria e conteúdo de C e N, evidenciando os baixos níveis de carbono nas partículas e a classificação arenosa dos sedimentos, cuja granulometria mostrou-se relevante na dinâmica dos metais no ecossistema aquático. Não houveram indícios de que o sedimento do rio estivesse contaminado por elementos metálicos. As partículas finas (<63 µm) dos sólidos em suspensão, com maiores teores de carbono, foram responsáveis pelo transporte desses elementos até o rio Piracicaba. A qualidade da água, medida através do IQA, foi considerada Boa, à exceção dos pontos de coleta 6 e 7 que sofrem maior impacto devido ao despejo de efluentes do município de Rio Claro e do bairro Santa Teresinha, e foram classificados com qualidade Aceitável em três épocas de coleta. / Total and exchangeable levels of aluminum, arsenic, cadmium, cupper, iron, manganese, mercury, nickel, plumb and strontium, were determined in sediment samples from Corumbataí river. The measurements for the elements quantification were made by atomic emission spectrometry with inductively coupled plasma (ICP-AES), neutron activation analyses (NAA) and atomic fluorescence spectrometry (AFS). The samples for total metals load determination, quantified by ICP-AES and AFS were extracted in Teflon bombs with aqua regia. Cold extraction with HCl 1,0 M was used for the quantification of exchangeable metals. As were quantified by AFS through hydride generation technique. For results comparison, Fe, Cr and As were also analyzed by NAA, method that the sample was irradiated with 1012n cm-2 s-1 thermal neutrons flux and the element determination is made by gamma ray spectrometry through the radionucleotideos radiation emission. The sediment samples were collected in seven sites in the Corumbataí River, in March, August and November 2004 and February 2005. Superficial water sampling for the determination of physics, chemical and biological variables which set up the Water Quality Index IQA, commended by CETESB, were made concomitantly. In the rainy period, corresponded to November 2004 and February 2005, were collected suspended solids that went through the same procedures described for sediment. The sample were grain size, C and N percentage characterized becoming evident the low levels of carbon and the sediment classification as sandy, in which the grain size show up relevant in the metals dynamics in that aquatic environment. There were no indications of metallic elements contamination in the Corumbataí River. The suspended matter clay particles (<63 µm), with higher carbon levels in which are adsorbed greater quantities of metals are responsible for these elements transport for the Piracicaba river. The water quality, measured through IQA is Good, exception made to the 6 and 7 sites that received greater impact due to the effluents discharge from counties of Rio Claro, Santa Gertrudes and the district of Santa Teresinha, and were classified as Acceptable in three sampling times.
47

Estimativa de taxas de denudação mecânica da bacia hidrográfica do Rio Quatorze (PR) pela análise de sólidos em suspensão / Estimate rate of mechanical denudation River Basin Quatorze (PR) the analysis of solid suspension

Aguiar, Wagner de 27 February 2012 (has links)
Made available in DSpace on 2017-07-10T17:31:22Z (GMT). No. of bitstreams: 1 Wagner_de_Aguiar.pdf: 11388693 bytes, checksum: 2d568f29c8d953e3f9cb683f0a508900 (MD5) Previous issue date: 2012-02-27 / The object of this paper is to estimate the mechanical denudation rates for the river basin Quatorze in the sectors of the upper valley and the mouth of the river. The basin is located in the municipality of Francisco Beltrão, in Paraná, draining the left bank of the middle valley of the river basin Marrecas. Monitoring the field began in august 2011, rising daily data of rainfall, flow and concentration of suspended solids in the sections of the channels drained the upper valley and the mouth of the river, to obtain the discharges suspended solids. Carrying out further surveys in ten soil profiles distributed throughout the basin, allowing the identification of the main soil classes (Regolithic Entisols, Inceptisols, Oxisols and Nitossolos) and the measurement of laboratory parameters such as density and real, total porosity and fines content (silt and clay). In the monitored period was recorded daily rainfall, which occurred on august 19, 165 mm, resulting in large peak flows and discharge of suspended solids, contributing to the total rainfall for the month of august 2011, 343 mm, reached the highest monthly index for the month of august, the last 37 years, according to data provided by the Meteorological Station of Francisco Beltrão. Recognizing that the largest fraction pedological removed by the force of runoff is composed of mud (silt and clay), this parameter was quantified for soils of the basin, yielding an average of 91.87%. From the data of total suspended solid discharge (1,616.54 tons. in the upper valley and 5960.38 tons. at the mouth) and the average density (1.05 g.cm-³) of soil profiles were estimated denudation rates for the month of august 2011, 0.0419 mm in the sector of the basin drained by the upper valley and 0.0527 mm in the area drained by the mouth of the river. These results were extrapolated to annual estimates, based on the monitored period of rainfall and monthly average of the years 1974 to 2010. The standard deviations of the average monthly rainfall, for those years, enabled the establishment of maximum and minimum estimates for the annual rates of denudation. The sector of the upper valley had average estimate of 0.2458 mm.yr-¹ can vary over a range of 0.1069 mm.yr-¹ to 0.3848 mm.yr-¹, while the sector had the mouth of the river estimated annual average higher, 0.3092 mm.yr-¹ may, however, vary in a range of 0.1344 mm.yr-¹ to 0.4840 mm.yr-¹. / O objeto de estudo deste trabalho é estimar as taxas de denudação mecânica para a bacia hidrográfica do rio Quatorze, nos setores do Alto Vale e da Foz do rio. A bacia está localizada no município de Francisco Beltrão, no Sudoeste do Paraná, drenando a margem esquerda do médio vale da bacia do rio Marrecas. O monitoramento a campo iniciou-se no mês de agosto de 2011, levantando-se dados diários de pluviosidade, de vazão e de concentração de sólidos em suspensão, nas seções dos canais drenados pelo Alto Vale e pela Foz do rio, para a obtenção das descargas sólidas em suspensão. Realizando-se na sequência levantamentos de solos em dez perfis distribuídos pela bacia, possibilitando a identificação das principais classes de solo (Neossolos regolítico, Cambissolos, Nitossolos e Latossolos) e a quantificação laboratorial dos parâmetros como densidade aparente e real, porosidade total e teor de finos (silte e argila). No período monitorado foi registrada pluviosidade diária, ocorrida no dia 19 de agosto, de 165 mm, provocando grandes picos de vazão e descarga de sólidos em suspensão, contribuindo para que a pluviosidade total do mês de agosto de 2011, 343 mm, atingisse o maior índice mensal, para os meses de agosto, dos últimos 37 anos, de acordo com dados fornecidos pela Estação Meteorológica de Francisco Beltrão. Reconhecendo-se que a maior fração pedológica removida pela força do escoamento superficial é composta pela lama (silte e argila), quantificou-se este parâmetro para os solos da bacia, obtendo-se um valor médio de 91,87%. A partir dos dados de descarga sólida em suspensão total (1.616,54 ton. no Alto Vale e 5.960,38 ton. na Foz) e da densidade aparente média (1,05 g.cm-³) dos perfis de solo, foram estimadas as taxas de denudação, para o mês de agosto de 2011, em 0,0419 mm no setor da bacia drenado pelo Alto Vale e 0,0527 mm no setor drenado pela Foz do rio. Resultados estes extrapolados para estimativas anuais, tendo como base as pluviosidades do período monitorado e das médias mensais dos anos de 1974 a 2010. Os desvios padrões das pluviosidades médias mensais, dos referidos anos, possibilitaram o estabelecimento de estimativas máximas e mínimas para as taxas de denudação anual. O setor do Alto Vale apresentou estimativa média de 0,2458 mm.ano-¹ podendo variar em uma faixa de 0,1069 mm.ano-¹ a 0,3848 mm.ano-¹, enquanto que o setor da Foz do rio apresentou estimativa média anual, mais elevada, de 0,3092 mm.ano-¹, podendo, no entanto, variar em uma faixa de 0,1344 mm.ano-¹ a 0,4840 mm.ano-¹.
48

Estimativa de taxas de denudação mecânica da bacia hidrográfica do Rio Quatorze (PR) pela análise de sólidos em suspensão / Estimate rate of mechanical denudation River Basin Quatorze (PR) the analysis of solid suspension

Aguiar, Wagner de 27 February 2012 (has links)
Made available in DSpace on 2017-05-12T14:42:51Z (GMT). No. of bitstreams: 1 Wagner_de_Aguiar.pdf: 11388693 bytes, checksum: 2d568f29c8d953e3f9cb683f0a508900 (MD5) Previous issue date: 2012-02-27 / The object of this paper is to estimate the mechanical denudation rates for the river basin Quatorze in the sectors of the upper valley and the mouth of the river. The basin is located in the municipality of Francisco Beltrão, in Paraná, draining the left bank of the middle valley of the river basin Marrecas. Monitoring the field began in august 2011, rising daily data of rainfall, flow and concentration of suspended solids in the sections of the channels drained the upper valley and the mouth of the river, to obtain the discharges suspended solids. Carrying out further surveys in ten soil profiles distributed throughout the basin, allowing the identification of the main soil classes (Regolithic Entisols, Inceptisols, Oxisols and Nitossolos) and the measurement of laboratory parameters such as density and real, total porosity and fines content (silt and clay). In the monitored period was recorded daily rainfall, which occurred on august 19, 165 mm, resulting in large peak flows and discharge of suspended solids, contributing to the total rainfall for the month of august 2011, 343 mm, reached the highest monthly index for the month of august, the last 37 years, according to data provided by the Meteorological Station of Francisco Beltrão. Recognizing that the largest fraction pedological removed by the force of runoff is composed of mud (silt and clay), this parameter was quantified for soils of the basin, yielding an average of 91.87%. From the data of total suspended solid discharge (1,616.54 tons. in the upper valley and 5960.38 tons. at the mouth) and the average density (1.05 g.cm-³) of soil profiles were estimated denudation rates for the month of august 2011, 0.0419 mm in the sector of the basin drained by the upper valley and 0.0527 mm in the area drained by the mouth of the river. These results were extrapolated to annual estimates, based on the monitored period of rainfall and monthly average of the years 1974 to 2010. The standard deviations of the average monthly rainfall, for those years, enabled the establishment of maximum and minimum estimates for the annual rates of denudation. The sector of the upper valley had average estimate of 0.2458 mm.yr-¹ can vary over a range of 0.1069 mm.yr-¹ to 0.3848 mm.yr-¹, while the sector had the mouth of the river estimated annual average higher, 0.3092 mm.yr-¹ may, however, vary in a range of 0.1344 mm.yr-¹ to 0.4840 mm.yr-¹. / O objeto de estudo deste trabalho é estimar as taxas de denudação mecânica para a bacia hidrográfica do rio Quatorze, nos setores do Alto Vale e da Foz do rio. A bacia está localizada no município de Francisco Beltrão, no Sudoeste do Paraná, drenando a margem esquerda do médio vale da bacia do rio Marrecas. O monitoramento a campo iniciou-se no mês de agosto de 2011, levantando-se dados diários de pluviosidade, de vazão e de concentração de sólidos em suspensão, nas seções dos canais drenados pelo Alto Vale e pela Foz do rio, para a obtenção das descargas sólidas em suspensão. Realizando-se na sequência levantamentos de solos em dez perfis distribuídos pela bacia, possibilitando a identificação das principais classes de solo (Neossolos regolítico, Cambissolos, Nitossolos e Latossolos) e a quantificação laboratorial dos parâmetros como densidade aparente e real, porosidade total e teor de finos (silte e argila). No período monitorado foi registrada pluviosidade diária, ocorrida no dia 19 de agosto, de 165 mm, provocando grandes picos de vazão e descarga de sólidos em suspensão, contribuindo para que a pluviosidade total do mês de agosto de 2011, 343 mm, atingisse o maior índice mensal, para os meses de agosto, dos últimos 37 anos, de acordo com dados fornecidos pela Estação Meteorológica de Francisco Beltrão. Reconhecendo-se que a maior fração pedológica removida pela força do escoamento superficial é composta pela lama (silte e argila), quantificou-se este parâmetro para os solos da bacia, obtendo-se um valor médio de 91,87%. A partir dos dados de descarga sólida em suspensão total (1.616,54 ton. no Alto Vale e 5.960,38 ton. na Foz) e da densidade aparente média (1,05 g.cm-³) dos perfis de solo, foram estimadas as taxas de denudação, para o mês de agosto de 2011, em 0,0419 mm no setor da bacia drenado pelo Alto Vale e 0,0527 mm no setor drenado pela Foz do rio. Resultados estes extrapolados para estimativas anuais, tendo como base as pluviosidades do período monitorado e das médias mensais dos anos de 1974 a 2010. Os desvios padrões das pluviosidades médias mensais, dos referidos anos, possibilitaram o estabelecimento de estimativas máximas e mínimas para as taxas de denudação anual. O setor do Alto Vale apresentou estimativa média de 0,2458 mm.ano-¹ podendo variar em uma faixa de 0,1069 mm.ano-¹ a 0,3848 mm.ano-¹, enquanto que o setor da Foz do rio apresentou estimativa média anual, mais elevada, de 0,3092 mm.ano-¹, podendo, no entanto, variar em uma faixa de 0,1344 mm.ano-¹ a 0,4840 mm.ano-¹.
49

Modelling the Effect of Suspended Bodies on Cavitation Bubbles near a Ridgid Boundary using a Boundary Integral Approach

McGregor, Peter Stanley January 2003 (has links)
Cavitation is the spontaneous vaporisation of a liquid to its gaseous state due to the local absolute pressure falling to the liquid's vapour pressure (Douglas, Gasiorek et al. 1995). Cavitation is present in a wide range of mechanical systems ranging from ship screws to journal bearing. Generally, cavitation is unavoidable and may cause considerable damage and efficiency losses to these systems. This thesis considers hydraulic systems specifically, and uses a modified Greens equation to develop a boundary integral method to simulate the effect that suspended solid bodies have on a single cavitation bubble. Because of the limitations of accurately modelling cavitation bubbles beyond touchdown, results are only presented for cases up to touchdown. The aim of the model is to draw insight into the reasons there is a measurable change in cavitation erosion rate with increasing oil-in-water emulsion percentage. This principle was extended to include the effect that ingested particulates may have on cavitation in hydraulic machinery. Two particular situations are modelled; the first consists of stationary rigid particles in varying proximity to a cavitation bubble near a rigid boundary. The second case is similar; however the suspended particle is allowed to move under the influence of the pressure differential caused by the expanding/contracting cavitation bubble. Numerous characteristics of the domain are considered, including domain pressures and fluid field motion, and individual boundary surface characteristics. The conclusion of the thesis is that solid bodies, either stationary or moving, have little effect on the cavity from an energy perspective. Regardless of size or density, all energy transferred from the cavity to the solid body is returned indicating that there is no net change. As this energy is ultimately responsible for the peak pressure experienced by the domain (and hence responsible for eroding the rigid boundary) as the cavity rebounds, it then serves that a cavity with a solid body will rebound at the same pressure as a cavity without a suspended body present. If this is coupled with the observation that the cavity centroid at touchdown is largely unaffected by the presence of a suspension, then it would appear that the bubble near a solid would rebound at a very similar position as a cavity without a solid. Consequently, the damage potential of a cavity is unaffected by a suspension. However, there is one point of contention as the profile of the re-entrant jet of the cavity is altered by the presence of a suspension. As energy is radiated away from the cavity during penetration, it is possible that the shape of the jet may alter the rate that energy is radiated away during penetration. However, this requires further research to be definitive.
50

Análise do comportamento espectral das águas do reservatório da usina hidrelétrica Barra dos Coqueiros (GO) / Analysis of the spectral behavior of the reservoir waters of the Barra dos Coqueiros hydroelectric power plant (GO)

Santos, Ana Karoline Ferreira dos 20 August 2018 (has links)
Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-09-21T11:57:23Z No. of bitstreams: 2 Disssertação - Ana Karoline Ferreira dos Santos - 2018.pdf: 13536231 bytes, checksum: 731b9fe534131c66acaf4ffedc58a615 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-09-24T11:08:01Z (GMT) No. of bitstreams: 2 Disssertação - Ana Karoline Ferreira dos Santos - 2018.pdf: 13536231 bytes, checksum: 731b9fe534131c66acaf4ffedc58a615 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-24T11:08:01Z (GMT). No. of bitstreams: 2 Disssertação - Ana Karoline Ferreira dos Santos - 2018.pdf: 13536231 bytes, checksum: 731b9fe534131c66acaf4ffedc58a615 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-08-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The solar energy that arrives at the Earth surface is an essential phenomenon for the life maintenance and the knowledge of its dynamics contributes to the understanding of complex processes, like the water spectral behavior. Among the main properties that interact with electromagnetic radiation are chlorophyll "a" and suspended solids. In this sense, this study aims to analyze the influence of the Active Optical Components on the water spectral behavior of reservoirs of the Barra dos Coqueiros hydroelectric power plant (GO) at 40 data collection sites. To obtain the data, four field campaigns were carried out on February 10, 2016 and January 28, 2017 (higher precipitation) and 04 / August 4, 2016 and July 7, 2017 (lower precipitation). The spectral data were obtained using a portable spectroradiometer, FieldSpec® Hand Held model in spectral bands of 400 nm to 900 nm. The analysis of chlorophyll "a" followed the proposal of Mackinney (1941), suspended solid data followed Wetzel and Likens (1991; 2000) and APHA (1998; 2005) and the water transparency was according to Esteves (1998) and Peixoto et al. (2015). The analysis of the main information of the water bi-directional reflectance spectra occurred with the application of techniques: continuous removal, 1st and 2nd derivative, cluster analysis, surface reflectance extraction from the Landsat 8-OLI satellite image. Based on the results, there were several factors of performance in the spectral behavior of waters in Barra dos Coqueiros HPP reservoir, such as the climatic seasonality (rainy and dry periods) and the types of land use and occupation, due to the different agricultural production. These aspects favor higher values of suspended solids and chlorophyll a and lower water transparency in fields work of February/2016 and January 2017, resulting in higher reflectance in green (500 nm to 600 nm ) and red (600 nm at 700 nm) spectral ranges. In the field studies conducted in August/2016 and July/2017, reflectance influenced by suspended solids and chlorophyll a was low and the water transparency showed higher depth due to the higher levels of absorption of electromagnetic radiation in the water in the spectral bands of blue (400 nm to 500 nm) and infrared (700 nm to 900 nm). Thus, the geotechnologies applied in this study evidenced several possibilities for interpretation of water spectral information. / A energia solar que chega à superfície da Terra representa um fenômeno essencial para a manutenção da vida e o conhecimento de sua dinâmica contribui para a compreensão de processos complexos, como o comportamento espectral da água. Dentre as principais propriedades que interagem com radiação eletromagnética encontram-se a clorofila-a os sólidos em suspensão. Nessa perspectiva, o presente estudo tem por objetivo analisar em 40 pontos de coleta de dados, a influência dos Componentes Opticamentes Ativos no comportamento espectral das águas, do reservatório da Usina hidrelétrica Barra dos Coqueiros (GO). Para obtenção dos dados, foram realizadas quatro campanhas de campo, as quais ocorreram em 10/fevereiro/2016 e 28/janeiro/2017 (maiores precipitações) e 04/agosto/2016 e 07/julho/2017 (menores precipitação). Os dados espectrais, foram obtidos por meio de espectrorradiômetro portátil, modelo FieldSpec® Hand Held. A análise de clorofila-aseguiu a proposta de Mackinney (1941), os dados de sólidos em suspensão a metodologia de Wetzel e Likens (1991; 2000) e APHA (1998; 2005) e a transparência da água realizada conforme Esteves (1998) e Peixoto et al. (2015). O diagnóstico das principais informações dos espectros de reflectância da água ocorreu com aplicação de técnicas: remoção do contínuo, derivada, análise cluster, extração da reflectância de superfície da imagem do satélite Landsat 8-OLI. Com base nos resultados, verificou-se diversos fatores de atuação no comportamento espectral das águas do reservatório da UHE Barra dos Coqueiros (GO), como a sazonalidade climática (período chuvoso e seco) e as formas do uso e ocupação da terra, distintas pelas produções agrícolas, aspectos esses, que favorecem nos campos de fevereiro/2016 e janeiro/2017, valores mais elevados de sólidos em suspensão e clorofila-a menores transparência da água, resultando em maiores reflectância nas faixas espectrais do verde (500 nm a 600 nm) e vermelho (600 nm a 700 nm). Nos campos realizados em agosto/2016 e julho/2017, os níveis da reflectância influenciados por sólidos em suspensão e clorofila-asão baixas e as transparências da água apresentou maiores profundidade, devido a maior absorção da radiação eletromagnética na água nas bandas espectrais do azul (400 nm a 500 nm) e infravermelho (700 nm a 900 nm). Desse modo, as geotecnologias aplicadas neste estudo, evidenciaram diversas possiblidades para interpretação da informação espectral da água.

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