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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.
61

Emprego de biofiltro de pedra para remo??o de microalgas e s?lidos suspensos de efluentes de lagoas de estabiliza??o

Queiroz, Mois?s Andrade de Farias 28 February 2014 (has links)
Made available in DSpace on 2014-12-17T15:03:33Z (GMT). No. of bitstreams: 1 MoisesAFQ_DISSERT.pdf: 1322817 bytes, checksum: d69733a37de991cb265f0cf0939bee27 (MD5) Previous issue date: 2014-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This research evaluated the microalgae removal produced in a stabilization pond system using biofilters as post-treatment, besides characterizing the effluents of stabilization ponds and filters in relation to concentrations of algal biomass (chlorophyll a and suspended solids), organic matter (BOD and COD), total phosphorus, orthophosphate, pH and dissolved oxygen, and tried to correlate physicochemical parameters with chlorophyll "a". It was held at the Ponta Negra ETE which is constituted by three stabilization ponds, with a primary facultative pond and two of maturation. For the algae removal were used two submerged bio-filters: the filter FPF (Facultative Pond Filter), fed with facultative pond effluent; and the filter MPF (Maturation Pond Filter), fed with second maturation pond effluent. The filling material of both filters was predominantly gravel no. 2, although it contains portions of gravel no. 1 and no. 3. The filters operating conditions were bad, they were nearly 10 years without maintenance, without cleaning or removal of sludge since the time of its construction, and part of the filling material may be obstruct. Despite poor operating conditions were obtained satisfactory results, in level of posttreatment. Removal efficiencies in relation to BOD and COD were 7 and 25% in FPF and 9 and 19% and in MPF, respectively. In relation to TSS efficiencies in MPF and FPF were 37 and 20%, respectively. As for the chlorophyll "a" removal, the FPF efficiency was 44% and the MPF was 40%. There was 50% of consumption of dissolved oxygen, on average, within the filters. Two profiles were performed in the filters, and it was possible to conclude that variations throughout the day were not statistically significant, and that, regardless of the time of collection, they would have the same representation comparing to the time of data collection (7 am) and the daily average, although individual variations throughout the day have been shown to be significant. Another important observation is that the correlations between Chlorophyll a and TSS were bigger and more significant in the effluent of the filters than in the effluent of the ponds / A pesquisa avaliou a remo??o das microalgas produzidas em um sistema de lagoas de estabiliza??o utilizando biofiltros como p?s-tratamento, al?m de caracterizar os efluentes de lagoas de estabiliza??o e dos filtros no tocante ?s concentra??es de biomassa algal (clorofila a e s?lidos suspensos), mat?ria org?nica (DBO e DQO), ortofosfato, f?sforo total, pH e oxig?nio dissolvido, e buscou correlacionar os par?metros f?sico-qu?micos com a clorofila a . Foi realizada na ETE Ponta Negra que ? constitu?da por tr?s lagoas de estabiliza??o, sendo uma lagoa facultativa prim?ria e duas de matura??o. Para a remo??o das algas, foram utilizados dois biofiltros submersos: o filtro FLF -alimentado com efluente da lagoa facultativa; e o filtro FLM - alimentado com efluente da segunda lagoa de matura??o. O material de enchimento de ambos os filtros foi predominantemente brita n? 2, apesar de conter por??es de brita n? 1 e n? 3. As condi??es operacionais dos filtros eram p?ssimas, pois estavam h? quase 10 anos sem manuten??o, sem limpeza ou remo??o do lodo desde a ?poca da constru??o, podendo parte do material de enchimento estar colmatado. Apesar das condi??es operacionais prec?rias foram obtidos resultados satisfat?rios, em n?vel de p?s-tratamento. As efici?ncias de remo??o em rela??o ? DBO e DQO foram de 7 e 25% no FLF e 9 e 19% no FLM, respectivamente. Em rela??o aos SST as efici?ncias no FLF e FLM foram de 37 e 20%, respectivamente. Quanto ? remo??o de clorofila a , a efici?ncia no FLF foi de 44% e no FLM foi de 40%. Houve o consumo de 50% do oxig?nio dissolvido, em m?dia, no interior dos filtros. Foram realizados dois perfis nos filtros, e foi poss?vel concluir que as varia??es ao longo do dia n?o foram estatisticamente significativas, e que, independentemente do hor?rio da coleta, teriam a mesma representatividade ao comparar com o hor?rio da coleta da pesquisa (7 horas da manh?) e a m?dia di?ria, embora as varia??es pontuais ao longo do dia tenham se mostrado expressivas. Outra importante observa??o foi que as correla??es entre Clorofila a e SST foram maiores e mais significativas nos efluentes dos filtros do que nos efluentes das lagoas
62

An?lise do acoplamento de estruturas fractais em antenas monopolo multi-banda para comunica??o sem fio

Barreto, Edwin Luize Ferreira 18 November 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-17T19:09:01Z No. of bitstreams: 1 EdwinLuizeFerreiraBarreto_TESE.pdf: 4396827 bytes, checksum: 67d20b4064513759f618b9148557fcdd (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-17T21:47:01Z (GMT) No. of bitstreams: 1 EdwinLuizeFerreiraBarreto_TESE.pdf: 4396827 bytes, checksum: 67d20b4064513759f618b9148557fcdd (MD5) / Made available in DSpace on 2017-03-17T21:47:01Z (GMT). No. of bitstreams: 1 EdwinLuizeFerreiraBarreto_TESE.pdf: 4396827 bytes, checksum: 67d20b4064513759f618b9148557fcdd (MD5) Previous issue date: 2016-11-18 / Este trabalho tem como objetivo principal realizar o estudo e an?lise de diferentes antenas planares de microfita, atrav?s do emprego de geometrias fractais no patch ressoador e da remo??o parcial do plano de terra com acoplamento. Recentes estudos mostram que as varia??es nas formas geom?tricas do patch da antena e do plano de terra produzem mudan?as na distribui??o da densidade de corrente da estrutura e consequentemente nos modos ressonantes e na polariza??o da antena. No desenvolvimento desta tese, apresenta-se uma nova antena fractal que utiliza a t?cnica de inser??o de fendas e aberturas de forma fractal no plano de terra e tamb?m descontinuidades no transformador ? de onda na linha de transmiss?o a fim de aumentar a largura de banda e alcan?ar comportamentos espec?ficos em aplica??es de banda de frequ?ncia. Emprega-se o substrato FR-4 com dimens?es de 85,0 x 85,0 x 1,57 mm?. Al?m disso, usam-se diferentes modos de casamento de imped?ncia na linha de alimenta??o de antena como CPW (Coplanar Wave Guide) e altera??es da largura da linha de transmiss?o, a fim de obter varia??o na distribui??o de corrente e, consequentemente, na largura de banda de resposta por imped?ncia para S11 ? -10dB para banda C (3.9 GHz - 6,2 GHz) e banda S (2,0 GHz - 4,0 GHz). Uma an?lise comparativa de desempenho para a linha de microfita e CPW foi realizada, obtendo-se para alguns casos antenas circularmente polarizadas. Boa concord?ncia foi obtida entre os resultados medidos e simulados. / This work has as main objective to carry out the study and analysis of different planar microstrip antenna, by employing fractal geometry in the resonator patch and partial removal of the ground plane with coupling. Recent studies show that variations in geometric shapes of the antenna and the ground plane generate changes in current density distribution of the planar structure and consequently the resonant modes and antenna polarization. In developing this thesis presents a new fractal antenna using the technique of insertion slots and fractal shaped defects (gaps) in the ground plane and discontinuities with ? wavelength transformer in the transmission line in order to increase the bandwidth and inserting in the feed line to reach specific behaviors in three frequency bandwidth applications. We used the FR-4 substrate with dimensions of 85.0 x 85.0 x 1.57 mm?. In addition, we used different modes of impedance matching in line antenna feed as CPW (Coplanar Wave Guide), to change the width of the transmission line in order to obtain a variation in the current distribution and hence the response bandwidth impedance to S11 ? -10dB for C band (3.9 GHz - 6.2 GHz) and S band (2.0 GHz - 4.0 GHz). A comparative analysis of cases with microstrip line and CPW was made, applications in this frequency range require preferably circularly polarized antennas. Good agreement was obtained between measured and simulated results.
63

Centro de alto rendimiento para remo / High performance rowing center

Herrera Mendoza, Ana Claudia 29 September 2019 (has links)
El proyecto busca satisfacer las necesidades de un deportista de alto rendimiento de remo, para esto tiene zonas esenciales para su desarrollo y entrenamiento como un gimnasio con áreas para cardio (que incluye remoergometros) y musculación, una residencia, área de bienestar y rehabilitación, así como pozas de entrenamiento y el hangar de embarcaciones. Así mismo cuenta con una terraza para visitantes para eventos o días de competencia. La ubicación del proyecto es esencial porque al estar en un medio natural ayuda a la alta concentración del deportista y permite que el deporte se realice con eficacia, el lugar elegido es la “albufera de medio mundo” que es una laguna de 7km de largo, y que es propicia para la práctica del remo porque cuenta con aguas tranquilas las cuales son muy importantes para llevar a cabo del deporte, cabe resaltar el medio tranquilo, natural y aislado de la ciudad ayuda a la plena concentración. Ante este entorno natural y de conservación se ha optado por una construcción sostenible que respete y tenga compromiso con el medio ambiente, este implica el uso eficiente de la energía solar y el tratamiento del agua, la orientación del edificio para aprovechar los vientos y tener ventilación cruzada, así como un sistema constructivo de madera elevado sobre el nivel del suelo para reducir el impacto y que perdure ante la acción del medio costero. / The project seeks to satisfy the needs of a high performance rowing athlete, for this it has essential areas for its development and training as a gym with areas for cardio (which includes remoegometros) and fitness, a residence, wellness and rehabilitation area as well as rowing tanks and the boat storage. It also has a terrace for visitors for events or days of competition. The location of the project is essential because being in a natural environment helps the high concentration of the athlete and allows the sport to be carried out effectively, the chosen place is the "Albufera de Medio Mundo" which is a lagoon of 7km long, and that is conducive to the practice of rowing because it has calm waters which are very important to carry out the sport, it is worth highlighting the quiet, natural and isolated environment of the city helps the full concentration. Faced with this natural environment and conservation has opted for a sustainable construction that respects and is committed to the environment, this involves the efficient use of solar energy and water treatment, the orientation of the building to take advantage of the winds and have ventilation crossed as well as a constructive system of wood raised above ground level to reduce the impact and to last before the action of the coastal environment. / Tesis
64

Atmospheric Variability in Sulawesi, Indonesia / Regional Atmospheric Model Results and Observations / Atmosphärische Variabilität in Sulawesi, Indonesien / Ergebnisse und Beobachtungen zum regionalen, atmosphärischen Modell

Gunawan, Dodo 01 December 2006 (has links)
No description available.
65

Utiliza??o de microemuls?o na remo??o da cor de efluentes t?xteis contendo corantes dispersos

Ara?jo, Beth Aluana Tavares de 17 July 2009 (has links)
Made available in DSpace on 2014-12-17T15:41:51Z (GMT). No. of bitstreams: 1 BethATA_DISSERT.pdf: 4261945 bytes, checksum: f9ef7f539e59502be1e168b17a14bf4a (MD5) Previous issue date: 2009-07-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Polyester fibers are the most used fibers in the world and disperse dyes are used for dyeing these fibers. After dyeing, the colorful dyebath is discharged into effluent streams, which needs a special treatment for color removal. Surfactants interaction with dyes has been evaluated in several studies, including the textile area, specifically in the separation of dyes from textile wastewater. In this work a cationic surfactant was used in a microemulsion system for the extraction of anionic dyes (disperses dyes) from textile wastewater. These microemulsion system was composed by dodecylamonium chloride (surfactant), kerosene oil (organic phase), isoamyl alcohol (cosurfactant) and the wastewater (aqueous phase). The wastewater that results after the dyeing process is acid (pH 5). It was observed that changing the pH value to above 12.8 the extraction could be made, resulting in an aqueous phase with low color level. The Scheff? net experimental design was used for the extraction process optimization, and the obtained results were evaluated using the program "Statistica 7.0". The optimal microemulsion system was composed by 59.8wt.% of wastewater, 30.1wt.% of kerosene, 3.37wt.% of surfactant and 6.73wt.% of cosurfactant, providing extraction upper than 96%. A mix of reactive dyebath (50%) and disperse dyebath (50%) was used as aqueous phase and it presented extraction upper than 98%. The water phase after extraction process can be reused in a new dyeing, being obtained satisfactory results, according to the limits established by textile industry for a good dyeing. Tests were accomplished seeking to study the influence of salt addition and temperature. An experimental design was used for this purpose, which showed that the extraction doesn't depend on those factors. In this way, the removal of color from textile wastewater by microemulsion is a viable technique (that does not depend of external factors such as salinity and temperature), being obtained good extraction results even with in wastewater mixtures / Fibras de poli?ster s?o as fibras sint?ticas mais utilizadas no mundo e corantes dispersos s?o empregados para o tingimento destas fibras. Depois do tingimento, o banho colorido ? descarregado no efluente, que precisa de um tratamento especial para remo??o de cor. A intera??o de tensoativos com corantes foi estudada em diversas pesquisas inclusive na ?rea t?xtil, especificamente na separa??o de corantes de efluentes t?xteis. Neste trabalho foi usado um tensoativo cati?nico em um sistema de microemuls?o para extra??o de corantes n?oi?nico (corantes dispersos) de efluente t?xtil. Esse sistema de microemuls?o foi composto por cloreto de dodecil am?nio (tensoativo), querosene (fase org?nica), ?lcool isoam?lico (cotensoativo) e o efluente l?quido (fase aquosa). O efluente que resulta depois do processo de tingimento ? ?cido (pH 5). Foi observado que mudando o valor do pH para acima de 12,8 a extra??o poderia ser feita, resultando em uma fase aquosa com baixo n?vel de cor. Um planejamento experimental do tipo rede de Scheff? foi usado, para a otimiza??o do processo de extra??o, e os resultados obtidos foram avaliados usando o programa "Statistica 7.0". O ponto ?timo do sistema de microemuls?o ? composto por 59,8% em massa de efluente, 30,1% de querosene, 3,37% de tensoativo e 6,73% de cotensoativo, promovendo uma extra??o superior a 96%. Foi analisada a efici?ncia da remo??o da cor em um efluente composto por 50% de banho de corante reativo e 50% de banho de corante disperso, obtendo-se uma extra??o superior a 98%. A fase aquosa obtida ap?s a extra??o do corante pode ser reutilizada em um novo tingimento, obtendo-se resultados satisfat?rios, dentro dos limites estabelecidos para um bom tingimento na ind?stria. Tamb?m foram realizados testes que mostravam a influencia de fatores como a adi??o de sal e a varia??o da temperatura. Para isso foi utilizado um planejamento experimental, o qual mostrou que a extra??o n?o depende desses fatores. Dessa forma, a remo??o da cor de efluentes t?xteis por microemuls?o ? uma t?cnica vi?vel (que independe de fatores externos como salinidade e temperatura), obtendo-se inclusive bons resultados de extra??o em misturas de efluentes
66

Remo??o de ru?dos s?smicos utilizando transformada de wavelet 1D e 2D com software em desenvolvimento

Ecco, Daniel 05 April 2011 (has links)
Made available in DSpace on 2014-12-17T14:08:44Z (GMT). No. of bitstreams: 1 DanielE_DISSERT.pdf: 1217613 bytes, checksum: edb565b9e30a0c09780fcf4efd4a52dc (MD5) Previous issue date: 2011-04-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In the Hydrocarbon exploration activities, the great enigma is the location of the deposits. Great efforts are undertaken in an attempt to better identify them, locate them and at the same time, enhance cost-effectiveness relationship of extraction of oil. Seismic methods are the most widely used because they are indirect, i.e., probing the subsurface layers without invading them. Seismogram is the representation of the Earth s interior and its structures through a conveniently disposed arrangement of the data obtained by seismic reflection. A major problem in this representation is the intensity and variety of present noise in the seismogram, as the surface bearing noise that contaminates the relevant signals, and may mask the desired information, brought by waves scattered in deeper regions of the geological layers. It was developed a tool to suppress these noises based on wavelet transform 1D and 2D. The Java language program makes the separation of seismic images considering the directions (horizontal, vertical, mixed or local) and bands of wavelengths that form these images, using the Daubechies Wavelets, Auto-resolution and Tensor Product of wavelet bases. Besides, it was developed the option in a single image, using the tensor product of two-dimensional wavelets or one-wavelet tensor product by identities. In the latter case, we have the wavelet decomposition in a two dimensional signal in a single direction. This decomposition has allowed to lengthen a certain direction the two-dimensional Wavelets, correcting the effects of scales by applying Auto-resolutions. In other words, it has been improved the treatment of a seismic image using 1D wavelet and 2D wavelet at different stages of Auto-resolution. It was also implemented improvements in the display of images associated with breakdowns in each Auto-resolution, facilitating the choices of images with the signals of interest for image reconstruction without noise. The program was tested with real data and the results were good / Na atividade explorat?ria de hidrocarbonetos a grande inc?gnita ? a localiza??o das jazidas. Grandes esfor?os s?o empreendidos na tentativa de melhor identific?-las, localiz?-las e, ao mesmo tempo, otimizar a rela??o custo-benef?cio da extra??o de Petr?leo. Os m?todos s?smicos s?o os mais utilizados pelo fato de serem indiretos, isto ?, sondam as camadas de subsuperf?cie sem invadi-las. O sismograma ? a representa??o do interior da Terra e de suas estruturas atrav?s de um arranjo convenientemente disposto dos dados obtidos por meio da s?smica de reflex?o. Um grande problema nessa representa??o ? a intensidade e variedade de ru?dos presentes no sismograma, como o ru?do de rolamento superficial que contamina os sinais relevantes e pode mascarar as informa??es desejadas, trazidas por ondas espalhadas em regi?es mais profundas das camadas geol?gicas. Desenvolvemos uma ferramenta para suprimir estes ru?dos que usa transformadas Wavelets 1D e 2D. O programa, em linguagem Java, faz a separa??o das imagens S?smicas considerando as dire??es (horizontal, vertical e mistas ou locais) e faixas de comprimentos de ondas que formam essas imagens, usando Wavelets de Daubechies, Autoresolu??o que duplica o comprimento das ondas e Produto Tensorial das bases de Wavelets. Desenvolvemos a op??o, em uma mesma imagem, de usar o produto tensorial de Wavelets de dimens?o 2 ou produto tensorial de Wavelets de dimens?o 1 pelas identidades. Neste ?ltimo caso, temos a Decomposi??o em Wavelets de um sinal bidimensional em uma ?nica dire??o. Esta decomposi??o permite alongar numa determinada dire??o as Wavelets bidimensionais, corrigindo efeitos de escalas ao aplicarmos Autoresolu??es. Em outras palavras, aperfei?oamos o tratamento de uma imagem s?smica, usandoWavelet 1D eWavelet 2D em etapas diferentes de Autoresolu??es. Tamb?m implementamos melhorias na visualiza??o das imagens associadas ?s decomposi??es em cada Autoresolu??o, facilitando as escolhas das imagens com os sinais de interesse para reconstru??o da imagem sem os ru?dos. O programa foi testado com dados reais e os resultados obtidos foram de boa qualidade
67

Efici?ncia de uma ETE em escala real composta por reator UASB seguido de lodo ativado / Efficiency of a full-scale WWTP consists of UASB reactor followed by activated sludge

Ferraz, Danillo Luiz de Magalh?es 07 March 2014 (has links)
Made available in DSpace on 2014-12-17T15:03:34Z (GMT). No. of bitstreams: 1 DanilloLMF_DISSERT.pdf: 2643693 bytes, checksum: e8aa0f4d4535d4002a68928f7529ab75 (MD5) Previous issue date: 2014-03-07 / In the state of Rio Grande do Norte (RN), Brazil, there are about 80 sewage treatment systems being the predominant technology waste stabilization ponds. The Baldo s WWTP , due to its location and low availability of area, was designed as a hybrid conventional system (UASB reactor followed by activated sludge with biodiscs) at a tertiary level, being the most advanced WWTP in the State and also with the larger treatment capacity (1620 m3/h) .The paper presents the results of its performance based on samples collections from May to December 2012. Composite samples of the effluent of the grit chamber, UASB reactors, anoxic chambers, aeration tanks and treated effluent were collected weekly, every 4 hours for 24 hours. The results showed that the WWTP effluent presented adequate ranges of temperatures, pH and DO, however removal efficiencies of BOD and TSS were below the predicted by design. The UASB reactors also showed removals of BOD and TSS less than expected, due to the accumulation of sludge in the reactors, which eventually, was washed out in the effluent. The nitrification process was not satisfactory mainly due to problems in the oxygen distribution in the aeration tanks. The removal of ammonia and TKN were high, probably by the assimilation process / No Rio Grande do Norte (RN), Brasil existe cerca de 80 sistemas de tratamento de esgotos sendo a tecnologia das lagoas de estabiliza??o a predominantemente utilizada. A ETE do Baldo, devido a sua localiza??o e disponibilidade de ?rea foi concebida como um sistema convencional h?brido (UASB lodos ativados com biodiscos) em n?vel terci?rio, sendo a ETE mais avan?ada do Estado e com maior capacidade de tratamento (1620 m 3 /h). O trabalho apresenta os resultados do seu monitoramento, atrav?s de coletas realizadas semanalmente no per?odo de junho a dezembro de 2012, com base em amostras compostas coletadas a cada 4 horas, durante 24 horas, do efluente da caixa de areia, reatores UASB, c?maras an?xicas, tanques de aera??o e efluente tratado. Os resultados mostraram que a ETE apresentou efluentes com temperaturas, pH e OD adequados, entretanto efici?ncias abaixo do projetado para os par?metros DBO e SST. Os reatores UASB tamb?m apresentaram remo??es de DBO e SST abaixo do esperado, devido ao ac?mulo de lodo nos reatores, uma vez que, este era expelido no efluente. O processo de nitrifica??o n?o foi satisfat?rio, pelas baixas concentra??es de nitrato encontradas nos efluentes dos tanques de aera??o, provavelmente por problemas no sistema de aera??o. As remo??es de am?nia e NTK foram altas, provavelmente pelo processo de assimila??o
68

Velká Británie a mandátní území Mezopotámie, 1918-1926 / Great Britain and the Mandate for Mesopotamia, 1918-1926

Zamrzla, Martin January 2021 (has links)
The master thesis focuses on a more detailed analysis of the premises of British politics in relation to the Middle East after the First World War. Attention is focused especially on the territory of Mesopotamia, which is the center of all actions of neighboring states and the interests of the great powers. The thesis also includes the events of the war and the subsequent diplomatic negotiations held mostly at the Paris Peace Conference. Everything is viewed mainly from the perspective of British Empire and it's leaders. The finall goal of the work is to anchor the British mandates in the geographical area of the Middle East to the Ankara Agreement.

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