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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.
111

Modellierung der Interaktion zwischen Grundwasser und Kanalisation

Karpf, Christian 30 November 2012 (has links)
Der Austausch zwischen Grundwasser und Kanalnetz kann in die Prozesse der Grundwasserinfiltration in Kanalnetze und der Abwasserexfiltration aus Kanalnetzen unterteilt werden. Generell entstehen durch die In- und Exfiltration (I/E) erhöhte Kosten der Abwasserentsorgung und eine Belastung für Boden, Grundwasser und Oberflächenwasser. Für Einschätzungen zur Dynamik und Quantität der In- und Exfiltration ist die Nutzung von Modellen sinnvoll, da zahlreiche Einflussfaktoren in die Betrachtungen einfließen können und dadurch eine komplexe Erfassung der Prozessmechanismen ermöglicht wird. Im Rahmen der vorliegenden Arbeit wurden physikalisch basierte Modelle zur Abbildung der In- und Exfiltrationsprozesse hinsichtlich erforderlicher Parameter und Randbedingungen analysiert und angewandt. Anhand detaillierter 3D-Modelle, kleintechnischer Versuche, Datenanalysen und statistischer Verfahren erfolgte die Modifizierung und Entwicklung von I/E-Modellen sowie die Parameteridentifikation zur Abbildung der In- und Exfiltration. Des Weiteren wurden die entwickelten Modellansätze mit einem hydrodynamischen Kanalnetzmodell verknüpft und großräumige Langzeitsimulationen durchgeführt. Die Untersuchungen zeigen bezüglich der Infiltration von Grundwasser in das Kanalnetz, dass eine physikalisch basierte Prozessmodellierung einer Abstraktion bedarf, um die 3-Dimensionalität des Prozesses in einem 1D-Modell wieder zu geben und dadurch die Anbindung an ein Kanalnetzmodell zu ermöglichen. Anhand von Simulationsrechnungen wurde festgestellt, dass die quantitative Betrachtung der Infiltration auf Einzugsgebietsebene keine hydrodynamische Modellierung erfordert. Signifikante quantitative Änderungen der Grundwasserinfiltration aufgrund der Wasserstandsschwankungen in den Kanälen sind nur lokal oder temporär von Bedeutung. Die Grundwasserinfiltration kann jedoch deutliche Auswirkungen auf die Ergebnisse der hydrodynamischen Simulation haben. Anhand von Datenanalysen im Einzugsgebiet Dresden konnte des Weiteren ein signifikanter Zusammenhang zwischen Infiltrationsparametern und Kanalzustand ermittelt werden. Der Exfiltrationsprozess kann durch ein 1D-Modell gut abgebildet werden, wobei der Prozess der Bodenkolmation anhand eines zeit- und potenzialabhängigen Modells implementiert werden kann. Ferner konnte durch die Verknüpfung mit Infiltrationsanalysen eine Ableitung der Schadensfläche erfolgen, die als Parameter in die Exfiltrationsmodellierung eingeht. Die hydrodynamischen Berechnungen zeigen, dass für die Exfiltrationsmodellierung eine möglichst exakte Berechnung der Wasserstände in Kanalnetzen essentiell ist. / The water exchange between groundwater and sewer system can be characterized by the processes of groundwater infiltration and sewerage exfiltration. Infiltration and exfiltration (I/E) cause an increase of the costs of sewerage management and a deterioration of soil, groundwater and the receiving surface water. In order to assess the dynamics and quantities of I/E, model applications can be used in order to include influencing factors and to afford a complex consideration of the process mechanisms. Within this work I/E-approaches were analyzed and modified in order to assess parameters and boundary conditions. The parameter identification and model development was realised according to the application of a detailed 3D-model, the realization of experiments, data analyses and the application of statistical methods. Furthermore the developed and modified approaches were coupled with a hydrodynamic sewer network model and long term simulations were performed. It was found that a physical based description of the infiltration process requires the implementation of the 3-dimensionality of the process. A hydrodynamic modelling of the sewer flow processes is not necessary to quantify infiltration rates on catchment scale, but the results of hydrodynamic modelling can be influenced significantly by groundwater infiltration. Furthermore data analyses of data of Dresden show a significant relationship between infiltration parameters and the condition class of the sewer pipes. The exfiltration process can be described by a 1D-model, whereat the processes of soil clogging are simulated by a time and potential based approach. Using the infiltration analyses it was possible to calculate the leak area, which is an important parameter of the exfiltration modelling. Hydrodynamic simulations show that the exfiltration modelling requires an accurate calculation of water levels in sewers.
112

Rekonstrukce kanalizace v Brně / Reconstruction of sewer in Brno-City

Folovská, Kateřina January 2012 (has links)
The master thesis deals with the reconstruction of the sewerage in Brno-city, between the streets Roosveltova and Solniční. Due to the location of sewer in build-up area, the reconstruction will be performed by tunnelling technology – shield excavation. The thesis is mainly dedicate with design and structual design of sewer lining. The mathematical model is created in software Plaxis 8.2 2D.
113

Link Budget Maximization for a Mobile-Band Subsurface Wireless Sensor in Challenging Water Utility Environments

See, Chan H., Abd-Alhameed, Raed, Atojoko, Achimugu A., McEwan, Neil J., Excell, Peter S. 06 1900 (has links)
Yes / A subsurface chamber transceiver system and associated propagation channel link budget considerations for an underground wireless sensor system (UWSS) are presented: the application was a sewerage system for a water utility company. The UWSS operates over the GSM850/900, GSM1800/1900 and UMTS bands in order to operate with the standard public mobile phone system. A novel antenna was developed to minimize path loss from the underground location: a folded loop type, which is small enough to fit conveniently inside a utility manhole access chamber while giving adequate signal strength to link to mobile base stations from such a challenging environment. The electromagnetic performance was simulated and measured in both free space and in a real manhole chamber. An experimental test bed was created to determine the return loss and received signal strength with different transceiver positions below the manhole chamber access cover. Both numerical and experimental results suggested an optimum position of the unit inside the manhole, combining easy access for maintenance with viable received signal strength. This confirmed that the characteristics were adequate for incorporation in a transceiver designed to communicate with mobile base stations from underground. A field trial confirmed the successful operation of the system under severe conditions. / This work was supported partially by Yorkshire Innovation Fund, IETG Ltd. Contract, Research Development Project (RDP) and the European Union’s Horizon 2020 research and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424.
114

Etude du comportement des voûtes en maçonnerie renforcées par matériaux composites : Application aux ouvrages d'assainissement / Behavior of masonry vaults reinforced by composites materials : Application for sewerage systems

Saade, Maamoun 27 June 2012 (has links)
Les ouvrages d’assainissement en maçonnerie de meulière construits au 19ème siècle à Paris ont une forme ovoïdale et sont soumis à des sollicitations agressives qui ont largement augmenté depuis le début du 20ème siècle. Si la majorité de ces ouvrages continuent à fonctionner, leur état général se dégrade inexorablement. Comme la reconstruction n’est pas toujours possible pour des raisons de coût et d’impact social, la réhabilitation est la solution adoptée par de nombreux maîtres d’ouvrages. La thèse est une partie du projet RESAME qui a pour but de réduire les coûts de réhabilitation, d’améliorer la durabilité des réparations et de diminuer le temps d’intervention sur le site. L’objectif principal de la thèse est de mettre au point de nouvelles méthodes de restructuration plus économiques que les méthodes usuellement utilisées. Après avoir présenté les ouvrages d’assainissement et leurs types de dégradations. Les techniques d’auscultation et de réhabilitation sont données. Une synthèse bibliographique de l’application des matériaux composites sur des structures en maçonnerie est détaillée en première partie. Du fait de la géométrie et des matériaux, des voutes ont été substitué aux ovoïdes pour nos essais présentés en seconde partie. Deux procédés ont été mis au point au cours de la thèse : un chemisage mince par mortier fibré de 3 cm et un renforcement par collage de matériaux composites (Lamelles et tissus). Vingt voûtes ont subi un chargement jusqu’à la rupture. Le but de l’ensemble des essais est de déterminer les mécanismes de ruine, les charges de la première fissuration et les charges à la rupture. Un gain important est alors constaté pour les méthodes de renforcement. Les résultats obtenus sont présentés et discutés. / In 19th century, Sewerage systems constructed in Paris were egg-shaped and made of masonry. Collectors are subjected to aggressive loads which have largely increased since the early 20th century. Even, if the majority of structures are still in service, their general condition deteriorates inexorably, and as the reconstruction is not always possible for reasons of cost and social impact, rehabilitation is the solution adopted by many clients. The thesis is a part of the project RESAME designed to reduce rehabilitation costs, improve the durability of repairs and reduce response times on the site. The main objective of this thesis is to develop new methods of restructuring. After introducing sewerage systems and their types of damage, auscultation techniques and rehabilitation will be presented. A bibliographical survey of the application of composite materials on planes and curved structures masonry is detailed in first time. Because of the complexity of geometry and materials, the vaults were substituted by the ovoid for our tests presented in the second half. Two methods are developed in this thesis: a thin layer of fiber reinforced mortar (FRM) by 3 cm and reinforcement by composite materials. Twenty vaults have been loading up to failure. The purpose of the tests is to determine the failure mechanisms, the first cracking loads and breaking loads. An important gain is then observed as well as a delay in cracking for every reinforcement method. The results are presented and discussed. These two processes will be applicable on several projects soon.
115

Sistema condominial de coleta de esgoto e tratamento em decanto-digestor seguido de alagados construídos. Estudo de caso: município de Nova Redenção - BA / Condominial sewerage and treatment in septic tank followed by constructed wetlands. Case study: city of Nova Redenção - BA

Santiago, Aníbal da Fonseca 05 September 2008 (has links)
Este trabalho foi desenvolvido no município de Nova Redenção, localizado na região da Chapada Diamantina no estado da Bahia, nordeste brasileiro. Nesse município é grave o quadro de saneamento ambiental, assim como em outros do interior do Brasil. A falta de recursos financeiros e humanos é fator que dificulta a resolução desse problema. Acredita-se que estudos e aprimoramentos de tecnologias simplificadas de coleta e tratamento de esgoto doméstico que superem essas dificuldades estão em consonância com as peculiaridades dessas localidades e são, atualmente, tópicos importantes para pesquisa. Esta proposta teve como objetivo a concepção, instalação e avaliação de um sistema condominial de coleta de esgoto (SCE) em porção da zona urbana do município, onde moram, aproximadamente, 250 habitantes. Também se estudou a concepção, instalação e partida do sistema tratamento do esgoto - decanto-digestor seguido de alagados construídos de fluxo sub-superficial. Avaliou-se a aceitação do SCE pela comunidade e seu funcionamento. Caracterizaram-se os afluentes e efluentes das unidades do sistema de tratamento em termos de remoção da matéria orgânica (MO), sólidos (SST), nutrientes (N e P) e Escherichia coli. Realizou-se estudo da hidrodinâmica das unidades do sistema, com uso de traçador. Efetuou-se o balanço hídrico nos alagados. A rede condominial instalada mostrou-se, como em experiências de outros autores, satisfatória e adequada em sua aplicação em comunidades com características semelhantes à desse estudo. O aspecto da tecnologia do SCE mais estranhado pela comunidade foi o diâmetro utilizado para o esgotamento, devido, principalmente, ao receio que a tubulação entupisse. Não se registrou nenhuma queixa entre vizinhos quanto ao fato da rede passar dentro dos lotes. O sistema de tratamento estudado mostrou, depois de onze semanas de monitoramento, 85% de remoção de DQO e 86% de \'DBO IND.5\'; 90% de remoção de SST; a remoção de nitrogênio amoniacal, fósfoto total e solúvel foram de: 25%, 36% e 40%, respectivamente. A remoção de E. coli foi de 2,1 unidades logarítmicas. A areia utilizada, de granulometria muito fina, afetou sobremaneira a hidrodinâmica dos alagados construídos, fazendo com que houvesse uma lâmina sobre o material suporte. Isso diminuiu o tempo de detenção hidráulica dos alagados e pode ter ocasionado em menor eficiência do sistema. / This work was developed in the city of Nova Redenção, located in the region of the Chapada Diamantina in the state of Bahia, northeastern Brazil. In this city there are serious problems of environmental sanitation as well as in other within the country. Lack of financial and human resources is a factor that complicates the resolution of this problem. It is believed that studies and improvements in technologies for simplified collection and treatment of domestic sewage are in line with the peculiarities of these locations and are, today, important topics for research. This proposal was aimed at the design, installation and evaluation of a \'condominial\' sewerage (CS) in the village portion of the township, where live approximately 250 people. The objective of the study was also the design, installation and start of the sewage treatment system - septic tank followed by sub-superficial flow constructed wetlands. The acceptance of the CS by the community and its operation were evaluated. The treatment system was characterized in terms of removal of organic matter (OM), solids (TSS), nutrients (N and P) and Escherichia coli. The hydrodynamics of the system units was studied, using tracer. The water balance of constructed wetlands has been done. The \'condominial\' sewerage demonstrated, as well as in other experiences, good and proper application in communities with similar characteristics to this study. The community did not accept only the small diameter used, due mainly to their fear of clogging. Complaints from neighbors about the tubes passing through backyards were not registered. The treatment system study showed, after eleven weeks of monitoring, 85% of removal of COD and 86% of BOD5, 90% of removal of TSS, the removal of ammonia nitrogen, total and soluble fósfoto were: 25%, 36% and 40% respectively. The removal of E. coli was 2.1 logarithmic units. The sand used, of a very fine particle size, has particularly affected the hydrodynamics of the constructed wetlands, creating a sheet of water on the support material. It reduced the hydraulic detention time of the flooded water, which may be the cause of low efficiency.
116

A Private Commodity or Public Good? A Comparative Case Study of Water and Sanitation Privatization in Buenos Aires, Argentina, 1993-2006

Steurer, Erin 08 April 2008 (has links)
The water privatization project in Buenos Aires, Argentina between 1993 and 2006 serves as the main case study in this investigation. The study begins by introducing background information on neo-liberalism and free market capitalism and their role in promoting private sector participation in the water supply and sanitation (WSS) services industry. A comparative case study analysis of the Buenos Aires, Mexico City, Dolphin Coast, and United Kingdom case studies has revealed that there are some key similarities between the case studies. In the conclusion, the key similarities are analyzed to make broader implications about the nature of private sector participation in the WSS services industry.
117

Assessment of water quality changes resulting from municipal sewer installation in the Killbuck-Mud Creek Watershed, Indiana

Dobrowolski, Edward G. January 2008 (has links)
Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / Department of Natural Resources and Environmental Management
118

Constructing a Pipe-Bound City : A History of Water Supply, Sewerage, and Excreta Removal in Norrköping and Linköping, Sweden, 1860-1910

Hallström, Jonas January 2003 (has links)
In the mid- to late 19th century, modern pipe-bound water and sewer systems proliferated in European cities, a development that has sometimes been regarded as a necessary result of a sanitary awakening and the progress of science and technology. By analyzing the introduction and subsequent expansion of water, sewerage, and excreta collection on the local level, in the Swedish cities Norrköping and Linköping, this oversimplified picture is questioned. The main problematique of this dissertation is why piped water supply and sewerage were introduced in these two Swedish cities at this particular time in history, and why the systems were subsequently extended. The actor-network theory (ANT) is used as an analytical tool. In the local context issues of governance, economy, technology, public health, and environment were brought to a head, and, if anything stands out, it is the complexity of introducing new technology. Despite the differences between Norrköping and Linköping in terms of topography and social and economic structures, the evolution of water supply and sewerage was on the whole similar. The existence of uniform scientific, technological, ideological, and cultural influences and of legislation at the national level, coupled with suburban growth, contributed to this development. There was more variation in excreta collection, because of the differences between the cities. Poor sanitary conditions, a river sensitive to pollution, and a strong public health network caused Linköping to introduce sanitary regulations much earlier than Norrköping and in Linköping WC’s were not as common.
119

Uso da análise multicritério para a seleção de tecnologias de tratamento de efluentes / Use of multicriteria analysis to select the wastewater treatment technologies

Goffi, Andreia dos Santos 01 June 2017 (has links)
Fundação Araucária; CNPq / O elevado número de alternativas somado ao número de variáveis, que nem sempre são mensuráveis e muitas vezes são conflitantes, torna a escolha do sistema de tratamento de efluentes um difícil processo de decisão. A fim de assegurar que a melhor alternativa seja selecionada é necessário uma análise aprofundada, que considere o maior número de aspectos relacionados à tomada de decisão. Deste modo, este trabalho forneceu uma nova abordagem para a seleção de tecnologias de tratamento de águas residuais, considerando as dimensões econômicas, sociais, técnicas e ambientais. O modelo seguiu três etapas, sendo a primeira a definição das alternativas do modelo, as quais foram definidas através do estudo da viabilidade econômica de 37 tecnologias usuais no cenário brasileiro. Na segunda etapa, foram definidos dois grupos de critérios, de acordo com a vazão e a população, por meio da utilização do método de Copeland. E na terceira foi aplicado o método PROMETHEE II para ranqueamento das alternativas. Considerando os aspectos avaliados, as tecnologias infiltração lenta, infiltração rápida e lagoa anaeróbia seguida de lagoa facultativa foram as alternativas preferidas para as pequenas comunidades, ao passo que os sistemas UASB, seguido de póstratamento foram as opções menos preferidas. Para os centros urbanos as alternativas de destaque foram: infiltração rápida, reator UASB com filtro anaeróbio, já as de menor potencial foram os sistemas de lagoas. Os resultados contribuem para o desenvolvimento do saneamento, uma vez que o trabalho forneceu um processo de determinação mais robusto para seleção de tecnologias de tratamento, avaliando os critérios relevantes, como diretrizes para a determinação. / The high number of alternatives added to the number of variables, which are not always measurable and often conflicting, makes choosing the wastewater treatment system a difficult decision process. In order to ensure that the best alternative is selected, a depth analysis is required, which considers the greatest number of decision-making aspects. Therefore, this work has provided a new approach for the selection of wastewater treatment technologies, considering the economic, social, technical and environmental dimensions. The model has followed three stages: the first one was the definition of the model alternatives, which were defined through the economic viability study of 37 technologies usual in Brazil; in the second stage, two groups of criteria were defined, according to flow rate and population, using the Copeland method; and in the third one, the PROMETHEE II method was applied in order to rank the alternatives. Considering the aspects evaluated, the technologies as slow and fast infiltration, anaerobic pond followed by facultative pond were the preferred alternatives for small communities, while UASB systems followed by post-treatment were the less preferred options. For the urban groups the preferred alternatives were: fast infiltration, UASB reactor with anaerobic filter, while the ones with the least potential were the pond systems. The results contribute to the sanitation development, since the work has provided a robust determination process for the selection of the treatment technologies, by evaluating the most relevant criteria.
120

Důvody odlišnosti cen vody (vodného a stočného) v jihočeském regionu na příkladech vybraných měst Vodňany a Prachatice / The reasons for differences in prices of water (water and sewage) in South Bohemia on the examples of selected towns Vodňany and Prachatice

DANIELOVÁ, Markéta January 2016 (has links)
The subject of my diploma thesis, "The reasons for differences in prices of water (water and sewage) in South Bohemia on the examples of selected towns Vodňany and Prachatice" is to analyze the pricing of water and sewage, and their development in the period between 2006 to 2014 in the towns Vodňany and Prachatice and find the main reasons for the differences in these prices between these two towns.

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