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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.
141

Removal of perchlorate in ammunition wastewater by zero-valent iron and perchlorate respiring bacteria

Ahn, Se Chang. January 2008 (has links)
Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisor: Daniel K. Cha, Dept. of Civil & Environmental Engineering. Includes bibliographical references.
142

Reuse of domestic greywater for the irrigation of food crops

Finley, Sara. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Bioresource Engineering. Title from title page of PDF (viewed 2009/06/23). Includes bibliographical references.
143

Integration of wastewater treatment in agro-ecosystems /

Geber, Ulrika. January 2000 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2000. / Includes bibliographical references.
144

Development of a complete process integration framework for wastewater minimisation in batch processes

Gouws, Jacques Francois. January 2009 (has links)
Thesis (Ph.D.(Chemical Engineering))--University of Pretoria, 2008. / Summary in English. Includes bibliographical references.
145

Επαναχρησιμοποίηση συχνότητας σε κινητά OFDMA δίκτυα

Καβουργιάς, Γεώργιος 06 October 2011 (has links)
Ο αριθμός των συνδρομητών κινητής τηλεφωνίας έχει αυξηθεί σημαντικά τα τελευταία χρόνια. Σε μεγάλο βαθμό οι φωνητικές υπηρεσίες εξυπηρετούνται από κινητά δίκτυα, ενώ παράλληλα αυξήθηκε σε μεγάλο βαθμό η χρήση των δεδομένων στα δίκτυα εκείνα που εφαρμόστηκε το 3GPP High Speed Packet Access (HSPA), αποδεικνύοντας ότι οι χρήστες επιδοκιμάζουν τη χρήση δεδομένων που παρέχονται ασύρματα με ευρυζωνικές ταχύτητες. Ο μέσος αριθμός χρήσης δεδομένων ξεπερνά τα εκατοντάδες megabytes ανά χρήστη κάθε μήνα. Τα ασύρματα δίκτυα πρέπει να αυξήσουν τις ταχύτητες μετάδοσης δεδομένων έτσι ώστε να πλησιάσουν εκείνες της ενσύρματης επικοινωνίας. Οι χρήστες είναι συνηθισμένοι να χρησιμοποιούν ενσύρματα δίκτυα και έτσι περιμένουν από τα ασύρματα δίκτυα να προσφέρουν συγκρίσιμες αποδόσεις με χαμηλό κόστος μετάδοσης δεδομένων. Το 3GPP Long Term Evolution (LTE) είναι σχεδιασμένο να επιτύχει αυτούς τους στόχους. Η τεχνολογία LTE προσφέρει κλιμακωτό εύρος ζώνης (απο 1.25 έως 20 MHz) με ρυθμούς μετάδοσης στα 100 Mbps για τον κατερχόμενο σύνδεσμο και στα 50 Mbps για τον ανερχόμενο. Αυτές οι πτυχές συνοδευόμενες από την τεχνολογία πρόσβασης που χρησιμοποιείται, η οποία είναι η OFDM (Orthogonal frequency division multiplexing), βελτιώνουν τη ρυθμαπόδοση του χρήστη και τη χωρητικότητα, ενώ μειώνουν τις καθυστερήσεις προσφέροντας παράλληλα βελτιωμένες συνθήκες κατά την κινητικότητα του χρήστη. Η OFDM προσφέρει επίσης μεγαλύτερη ανέχεια σε φαινόμενα όπως η εξασθένιση και το multipath σε σύγκριση με τεχνολογίες που εφαρμόζονταν σε προηγούμενα δίκτυα. Επίσης, είναι σημαντικό να αναφερθεί ότι το LTE χρησιμοποιεί τη μεταγωγή πακέτων και χρησιμοποιεί την τεχνολογία πολλαπλών κεραιών καθώς επίσης πολυπλεξία στο επίπεδο του χρόνου και της συχνότητας. Τέλος, υποστηρίζει unicast και multicast μετάδοση, τόσο σε microcell (κελιά μικρότερου εύρους) όσο και macrocell (μεγαλύτερα κελιά) περιβάλλον. Το αντικείμενο που μελετάται σε αυτή τη διπλωματική είναι το πρόβλημα του περιορισμού των παρεμβολών οι οποίες επηρεάζουν σε μεγάλο βαθμό την απόδοση των LTE συστημάτων. Ιδιαίερη μελέτη γίνεται όσο αφορά στην Inter Cell παρεμβολή και στις Inter Cell Interference Coordination τεχνικές. Συγκεκριμένα, η έρευνα εστιάζει στη βελτίωση της απόδοσης των χρηστών μειώνοντας την παρεμβολή μέσω διαφόρων σχημάτων επαναχρησιμοποίησης συχνότητας. / The number of mobile subscribers has increased tremendously in recent years. Voice communication has become mobile in a massive way and the mobile is the preferred way for voice communication. At the same time the data usage has grown fast in those networks where 3GPP High Speed Packet Access (HSPA) was introduced indicating that the users find value in broadband wireless data. The average data consumption exceeds hundreds of Megabytes per subscriber per month. Wireless networks must make data rates higher in order to match the user experience provided by wireline networks. When customers are used to wireline performance, they expect the wireless network to offer comparable performance with low cost of data delivery. 3GPP Long Term Evolution (LTE) is designed to meet those targets. LTE technology offers scalable bandwidth (from 1.25 up to 20 MHz), with transmission rates of 100 Mbps in downlink and 50 Mbps in uplink. These aspects accompanied with the access technology used, which is the OFDM (Orthogonal frequency division multiplexing), improves end-user throughputs, sector capacity and reduces user plane latency, bringing significantly improved user experience with full mobility. OFDM also offers bigger tolerance in phenomena such as multipath and fading compared to technologies used in previous mobile networks. It is also important to be mentioned that LTE is fully packet switched and uses multiple antenna techniques along with FDD and TDD duplexing. Finally, it supports unicast and multicast transmission, in both microcell and macrocell environment. The subject studied in this thesis is the problem of mitigating Interferences which dramatically affects the performance of LTE system. Extensive study is done concerning Inter Cell Interference and Inter Cell Interference Coordination techniques. In particular, research focuses in enhancing users’ performance by reducing interference via varius schemes of frequency reuse.
146

O reaproveitamento de notícias no jornalismo impresso contemporâneo : o caso do Caderno Diplô, do Le Monde Diplomatique Brasil /

Pinto, Fernanda Iarossi. January 2010 (has links)
Orientador: Maximiliano Martin Vicente / Banca: Danilo Rothberg / Banca: Andreu Casero Ripollés / Resumo: O presente trabalho tem como objetivo elencar características que definem o jornalismo resultante do reaproveitamento de notícias já publicadas no meio impresso. Por meio da análise qualitativa do discurso, da representação estrutural temática e da teia argumentativa de três edições dos Cadernos Diplô, publicações derivadas do jornal mensal Le Monde Diplomatique, e da trajetória dos paradigmas construtivista (teorias estruturalista e interacionista), do gatekeeper ao newsmaking - que marcam as teorias do jornalismo -, foi possível concluir que o reaproveitamento de notícia é uma prática editorial e não uma categoria específica dentro do jornalismo, pode contribuir para amenizar a "miopia" de que a comunidade interpretativa, ou seja, os próprios jornalistas sofrem, e apresenta-se como alternativa diante da necessidade imediatista, que pauta o jornalismo orientado pelo presente. Além de ser uma saída também ao critério de atualidade ou o factualidade que molda o jornalismo comercial/industrial (que considera a notícia como uma mercadoria a ser comercializada), funciona como um processo de otimização da gestão da informação e preserva memórias e análises de questões importantes para a história do homem / Abstract: The present work has as main objective indicate some characteristics that define the resulting journalism from the reuse of still published news is printed journalism. Through the discourse qualitative analysis, thematic depiction and the argumentative web of the three issues of Cadernos Diplô, derivative publications from monthly newspaper Le Monde Diplomatique, and the trajectory of constructivist paradigms (structuralist and interacionist theories), gatekeeper and newsmaking that mark the journalism theories, it was possible to conclude that the reuse of news is an editorial practice and not a particular category within journalism, and it can contribute to ease the "myopia" that the interpretative community, meaning, the journalists suffer, and it is presented as an alternative facing the journalistic necessity which characterize the focused journalist by the present. Beyond being an alternative also to the present criterion or the factually the mold the commercial/industrial journalism (that consider the news as goods to be commercialized), work as an optimization process in the information management and to preserve memories and analyses which are important human being history / Mestre
147

Applying a semantic layer in a source code retrieval tool

Durão, Frederico Araujo 31 January 2008 (has links)
Made available in DSpace on 2014-06-12T15:51:21Z (GMT). No. of bitstreams: 1 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / O reuso de software é uma área de pesquisa da engenharia de software que tem por objetivo prover melhorias na produtividade e qualidade da aplicação através da redução do esforço. Trata-se de reutilizar artefatos existentes, ao invés de construí-los do zero a fim de criar novas aplicações. Porém, para obter os benefícios inerentes ao reuso, alguns obstáculos devem ser superados como, por exemplo, a questão da busca e recuperação de componentes. Em geral, há uma lacuna entre a formulação do problema, na mente do desenvolvedor e a recuperação do mesmo no repositório, o que resulta em resultados irrelevantes diminuindo as chances de reuso. Dessa maneira, mecanismos que auxiliem na formulação das consultas e que contribuam para uma recuperação mais próxima à necessidade do desenvolvedor, são bastante oportunos para solucionar os problemas apresentados. Nesse contexto, este trabalho propõe a extensão de uma ferramenta de busca por palavra-chave através de uma camada semântica que tem por objetivo principal aumentar a precisão da busca e, conseqüentemente, aumentar as chances de reuso do componente procurado. A criação da camada semântica é representada basicamente por dois componentes principais: um para auxiliar o usuário na formulação da consulta, através do uso de uma ontologia de domínio, e outro para tornar a recuperação mais eficiente, através de uma indexação semântica dos componentes no repositório
148

Test case prioritization based on data reuse for Black-box environments

Lima, Lucas Albertins de 31 January 2009 (has links)
Made available in DSpace on 2014-06-12T15:53:11Z (GMT). No. of bitstreams: 2 arquivo1906_1.pdf: 1728491 bytes, checksum: 711dbaf0713ac324ffe904a6dace38d7 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Albertins de Lima, Lucas; Cezar Alves Sampaio, Augusto. Test case prioritization based on data reuse for Black-box environments. 2009. Dissertação (Mestrado). Programa de Pós-Graduação em Ciência da Computação, Universidade Federal de Pernambuco, Recife, 2009.
149

Microbial-based evaluation of anaerobic membrane bioreactors (AnMBRs) for the sustainable and efficient treatment of municipal wastewater

Harb, Moustapha 03 1900 (has links)
Conventional activated sludge-based wastewater treatment is an energy and resource-intensive process. Historically it has been successful at producing safely treated wastewater effluents in the developed world, specifically in places that have the infrastructure and space to support its operation. However, with a growing need for safe and efficient wastewater treatment across the world in both urban and rural settings, a paradigm shift in waste treatment is proving to be necessary. The sustainability of the future of wastewater treatment, in a significant way, hinges on moving towards energy neutrality and wastewater effluent reuse. This potential for reuse is threatened by the recent emergence and study of contaminants that have not been previously taken into consideration, such as antibiotics and other organic micropollutants (OMPs), antibiotic resistance genes, and persistent pathogenic bacteria. This dissertation focuses on investigating the use of anaerobic membrane bioreactor (AnMBR) technology for the sustainable treatment of municipal-type wastewaters. Specifically, a microbial approach to understanding biofouling and methane recovery potential in anaerobic MBR systems has been employed to assess different reactor systems’ efficiency. This dissertation further compares AnMBRs to their more widely used aerobic counterparts. This comparison specifically focuses on the removal and biodegradation of OMPs and antibiotics in both anaerobic and aerobic MBRs, while also investigating their effect on the proliferation of antibiotic resistance genes. Due to rising interest in wastewater effluent reuse and the lack of a comprehensive understanding of MBR systems’ effects on pathogen proliferation, this dissertation also investigates the presence of pathogens in both aerobic and anaerobic MBR effluents by using molecularbased detection methods. The findings of this dissertation demonstrate that membrane-associated anaerobic digestion processes have significant potential to improve the sustainability of wastewater treatment. This is exemplified by attributes of AnMBR systems associated with both increased system efficiency and wastewater reuse potential through methane recovery and lower abundance of effluent microbial contaminants, respectively. Overall, the studies collated in this dissertation have shown that understanding the microbial communities of AnMBRs can play a central role in further improving these attributes and in reducing the risks posed by emerging contaminants and pathogens in wastewater treatment systems.
150

Reuse of steel and aluminium without melting

Cooper, Daniel January 2014 (has links)
Carbon dioxide emissions must be dramatically reduced to avoid the potentially dangerous effects of climate change. The steel and aluminium industries produce large amounts of carbon dioxide, accounting for 6% of anthropogenic emissions. Previous studies have shown that in these industries there is limited scope for further improvements in energy efficiency. Material efficiency strategies can, however, further reduce emissions. This thesis focuses on materially efficient reuse without melting. A scoping study of current reuse found three opportunities, an examination of which forms the basis of this thesis: reusing components at end of product life; extending the lifespan of products; and reusing manufacturing scrap. The opportunity to reuse components has received little attention to date and there is no clearly defined set of strategies or barriers to enable assessment of appropriate component reuse; neither is it possible to predict future levels of reuse. This thesis presents a global assessment of the potential for reusing steel and aluminium components. A combination of top-down and bottom-up analyses is used to allocate the final destinations of current global steel and aluminium production to final products. A substantial catalogue has been compiled for these products characterizing key features of steel and aluminium components including design specifications, requirements in use, and current reuse patterns. To estimate the fraction of end-of-life metal components that could be reused for each product, the catalogue formed the basis of a set of semi-structured interviews with industrial experts. The results suggest that approximately 30% of steel and aluminium used in current products could be reused. Barriers against reuse are examined, prompting recommendations for redesign that would facilitate future reuse. In order to understand how product lifespans can be extended it must first be understood why products are replaced. A simple framework with which to analyse failure is applied to the products that dominate steel use, finding that they are often replaced because a component/sub-assembly becomes degraded, inferior, unsuitable or worthless. In light of this, four products, which are representative of high steel content products in general, are analysed at the component level, determining profiles of cumulative steel mass over the lifespan of each product. The results show that the majority of the steel components are underexploited – still functioning when the product is discarded. In particular, the potential lifespan of the steel-rich structure is typically much greater than its actual lifespan. Evidence from twelve case studies, in which product or component life has been increased, is used to tailor life-extension strategies to each reason for product failure, providing practical guidelines for designers. There is currently no commercial method of reusing small manufacturing scrap; however, previous research has demonstrated that extruded profiles can be created from small clean aluminium scrap, the scrap fragments solid-state welding together when extruded. In order to evaluate potential applications for these profiles four case studies are conducted in collaboration with aluminium producers and product manufacturers. It was found that strong and formable profiles could be produced from scrap. However, contaminated scrap sources, unreliable bonding and poor surface quality limited their potential for commercial use. No model exists for solid-state weld strength that is applicable to scrap extrusion. This prevents optimisation of the existing extrusion process and the development of new, potentially better, processes. Subsequently, this thesis presents a new model of weld strength as a function of relevant deformation parameters. The model is evaluated using a new experiment in which the deformation conditions can be varied independently. The experiments establish the basic relationships between deformation parameters and weld strength. The model correctly predicts these trends with predicted weld strengths typically lying within the experimental error range. The technical assessment of reuse presented in this thesis demonstrates the scope of potential change. If implemented, the opportunities presented would greatly increase the reuse of steel and aluminium, reducing the emissions emitted from liquid metal production in conventional recycling.

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