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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

FTE-LEACH: um protocolo energeticamente eficiente e tolerante a falhas aplicado ?s redes industriais de sensores sem fio

Oliveira, Felipe Denis Mendon?a de 03 August 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-03T22:56:48Z No. of bitstreams: 1 FelipeDenisMendoncaDeOliveira_TESE.pdf: 5762435 bytes, checksum: f710387481b7dc41c1ff916b28138dbf (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-05T19:51:58Z (GMT) No. of bitstreams: 1 FelipeDenisMendoncaDeOliveira_TESE.pdf: 5762435 bytes, checksum: f710387481b7dc41c1ff916b28138dbf (MD5) / Made available in DSpace on 2016-05-05T19:51:58Z (GMT). No. of bitstreams: 1 FelipeDenisMendoncaDeOliveira_TESE.pdf: 5762435 bytes, checksum: f710387481b7dc41c1ff916b28138dbf (MD5) Previous issue date: 2015-08-03 / Uma Rede de Sensores sem Fio (RSSF) consiste de dispositivos distribu?dos em uma ?rea com a finalidade de monitorar vari?veis f?sicas, tais como temperatura, press?o, vibra??o, movimento e condi??es ambientais em locais onde as redes cabeadas seriam complicadas ou impratic?veis de serem implementadas, por exemplo, aplica??es industriais de dif?cil acesso, monitoramento e controle de po?os petrol?feros terrestres ou mar?timos, no acompanhamento de extensas ?reas de cultivo agr?rio e animal, entre outros. Para ser vi?vel, uma RSSF deve possuir requisitos importantes, tais como baixo custo, baixa lat?ncia e, principalmente, baixo consumo de energia. Entretanto, para garantir tais requisitos, essas redes sofrem limita??o de recursos, al?m de, eventualmente, serem utilizadas em ambientes hostis, levando a altas taxas de falhas, tais como roteamentos segmentados, perda de mensagens, reduzindo a efici?ncia podendo chegar, inclusive, a comprometer a rede como um todo. Este trabalho tem por objetivo apresentar o FTE-LEACH, um protocolo de roteamento energeticamente eficiente e tolerante a falhas, mantendo a efici?ncia na comunica??o e na dissemina??o de dados. Tal protocolo foi desenvolvido baseado no padr?o IEEE 802.15.4 e voltado ?s redes industriais com recursos energ?ticos limitados. / A Wireless Sensor Network (WSN) consists of distributed devices in an area in order to monitor physical variables such as temperature, pressure, vibration, motion and environmental conditions in places where wired networks would be difficult or impractical to implement, for example, industrial applications of difficult access, monitoring and control of oil wells on-shore or off-shore, monitoring of large areas of agricultural and animal farming, among others. To be viable, a WSN should have important requirements such as low cost, low latency, and especially low power consumption. However, to ensure these requirements, these networks suffer from limited resources, and eventually being used in hostile environments, leading to high failure rates, such as segmented routing, mes sage loss, reducing efficiency, and compromising the entire network, inclusive. This work aims to present the FTE-LEACH, a fault tolerant and energy efficient routing protocol that maintains efficiency in communication and dissemination of data.This protocol was developed based on the IEEE 802.15.4 standard and suitable for industrial networks with limited energy resources
42

Especifica??o e implementa??o de um algoritmo gen?tico para otimiza??o de projetos de ilumina??o p?blica / Specification and implementation of a genetic algorithm for optimization of public illumination projects

Oliveira, R?mulo Alves de 27 January 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-30T23:14:12Z No. of bitstreams: 1 RomuloAlvesDeOliveira_TESE.pdf: 1869244 bytes, checksum: af0453c8083aee85607b79c3a17c1d4c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-01T22:30:48Z (GMT) No. of bitstreams: 1 RomuloAlvesDeOliveira_TESE.pdf: 1869244 bytes, checksum: af0453c8083aee85607b79c3a17c1d4c (MD5) / Made available in DSpace on 2016-06-01T22:30:48Z (GMT). No. of bitstreams: 1 RomuloAlvesDeOliveira_TESE.pdf: 1869244 bytes, checksum: af0453c8083aee85607b79c3a17c1d4c (MD5) Previous issue date: 2015-01-27 / Atualmente os projetos de Ilumina??o P?blica (IP), ou seja, ruas, avenidas, pra?as, estacionamentos e similares s?o realizados com a utiliza??o de softwares comerciais ou livres, em geral, fornecidos por fabricantes ou grupos de fabricantes de produtos de ilumina??o, aplicando o M?todo Ponto a Ponto para o c?lculo dos n?veis de ilumina??o. Outros pontos em comum s?o: a falta de preocupa??o na redu??o dos custos dos projetos e a dificuldade em modificar as estruturas utilizadas, tais como: localiza??o e altura dos postes e lumin?rias, ?ngulo de inclina??o das lumin?rias, quantidade de lumin?rias por poste, entre outros. Qualquer altera??o nas estruturas ter? que ser feita manualmente, geralmente em um ambiente CAD, para depois obter os novos resultados e comparar com os anteriores. Para auxiliar nessa tarefa, ? proposta aqui a utiliza??o da Metaheur?stica Col?nia de Formigas, onde os par?metros e localiza??o das estruturas passam a ser definidos automaticamente, de forma a atender os n?veis de ilumina??o estabelecidos nas normas t?cnicas, al?m de otimizar o custo de material por unidade de ?rea. / The development of public lighting projects in Brazil must meet the standards established in Brazilian standards. Many of these projects is developed through the use of knowledge about "practical rules" practiced by the designers of this area. In some cases are also used computational tools offered, generally, by leading manufacturers of lamps/luminaires. These tools have served only as calculation tools, with some limitations, such as: are not able to verify compliance or not the parameters established by Brazilian standards, most of the luminaires offered in your database are not sold in Brazil, not have no concern about the analysis of the implementation costs of elaborate designs and, finally, present an enormous difficulty in performing tests on a large volume of possible projects. It is the goal of this thesis to develop a methodology and a computational tool for the development of public lighting projects based on genetic algorithm techniques that not only perform the calculations of these projects, but can also test several possible projects using in your database the luminaires marketed in Brazil, providing the user, as a solution, a set of projects that meet the Brazilian standards and classified according the implementation costs of each project. To adjust the proposed algorithm the following performance parameters were modified: number of individuals in the initial population; probability of achievement of the cross-over; probability of achievement of the mutation. A comparison of this method with the projects developed with the use of "practical rules" is performed for various types of existing roads. The results obtained using the proposed methodology and the developed computational tool show that the methodology, including the adjustments in performance parameters, is able to meet the objectives of the work.
43

S?ntese e caracteriza??es estrutural e magn?tica das ferritas de cobalto-mangan?s (Co1-xMnxFe2O4 E Co1,2Fe1,8-xMnxO4)

Amorim, Bruno Ferreira 07 December 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-10T19:03:35Z No. of bitstreams: 1 BrunoFerreiraAmorim_TESE.pdf: 4546675 bytes, checksum: f3babdd1005205365d367583411ae46c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-13T20:09:02Z (GMT) No. of bitstreams: 1 BrunoFerreiraAmorim_TESE.pdf: 4546675 bytes, checksum: f3babdd1005205365d367583411ae46c (MD5) / Made available in DSpace on 2016-06-13T20:09:02Z (GMT). No. of bitstreams: 1 BrunoFerreiraAmorim_TESE.pdf: 4546675 bytes, checksum: f3babdd1005205365d367583411ae46c (MD5) Previous issue date: 2015-12-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / As ferritas de cobalto-mangan?s (Co1?xMnxFe2O4 e Co1,2Fe1,8?xMnxO4) possuem uma estrutura do tipo espin?lio mista, e t?m sido consideradas como um das candidatas competitivas para grande variedade de aplica??es em dispositivos, desde a gera??o e detec??o de ultra-som, sensores, transformadores, bem como na ind?stria m?dica. Ferritas de cobaltomangan?s nanoestruturadas foram produzidas via moagem de alta energia, com subsequente tratamento t?rmico, e foram caracterizados por difra??o de raios X, fluoresc?ncia de raios X, microscopia eletr?nica de varredura e magnetiza??o. Amostras do tipo Co1?xMnxFe2O4 e Co1,2Fe1,8?xMnxO4 foram obtidas a partir dos p?s precursores Fe3O4, Co3O4 e Mn3O4, os quais foram estequiometricamente misturados e mo?dos por 10h e tratados termicamente ? 900?C por 2h. A difratometria confirma a forma??o das fases nanocristalinas puras para s?rie Co1,2Fe1,8?xMnxO4 com umdi?metro m?dio de cerca de 94nm. Verificou-se que o par?metro de rede aumenta com a substitui??o do Fe3? pelo Mn3?. A fluoresc?ncia de raios X revelou que as por??es de metais nas amostras estavam pr?xima das composi??es estequiom?tricas nominais. As caracter?sticas microestruturais observadas nas micrografias demonstraram que as part?culas formadas apresentam morfologia e granulometria bastante distintas. As medidas de histerese magn?ticas realizadas em baixa temperatura, mostraram que a magnetiza??o de satura??o e reman?ncia aumentaram com a concentra??o de mangan?s, enquanto que o campo coercivo diminuiu. A constante de anisotropia (Ke f ), foi calculada a partir dos ajustes dos dados pela lei de aproxima??o de satura??o. Verificou-se que a anisotropia diminui substancialmente com a substitui??o do ferro pelomangan?s. / The cobalt-manganese ferrites (Co1?xMnxFe2O4 and Co1,2Fe1,8?xMnxO4) has a mixed structure of spinel type and it has been regarded as one of candidates for petitive wide variety of applications in devices from ultrasonic generation and detection, sensors, transformers, as well as in medical industry. Ferrites cobalt-manganese nanostructured were produced via mechanical alloying with subsequent heat treatment and were characterized by X-ray diffraction, X-ray fluorescence, scanning electron microscopy and magnetization. Samples of Co1?xMnxFe2O4 and Co1,2Fe1,8?xMnxO4 were obtained from the precursor powders Fe3O4, Co3O4 and Mn3O4 which were stoichiometrically mixed and ground by 10h and heat treated at 900?C for 2h. The diffraction confirmed the formation of the pure nanocrystalline phases to series Co1,2Fe1,8?xMnxO4 with an average diameter of about 94nm. It was found that the lattice parameter increases with the substitution of Fe3? by Mn3?. The x-ray fluorescence revealed that the portions of metals in samples were close to the nominal stoichiometric compositions. The microstructural features observed in micrographs showed that the particles formed show very different morphology and particle size. The magnetic hysteresis measurements performed at low temperature showed that the saturation magnetization and remanence increased as the concentration of manganese, while the coercive field decreased. The anisotropy constant (Ke f ), was estimated from the data adjustments the law of approaching saturation. It was found that the anisotropy decreases substantially with the substitution of Fe by Mn.
44

Fator de decis?o na ado??o de um sistema de micro-cogera??o de energia a g?s natural :um estudo em Hot?is tr?s estrelas / Factor of decision to adoption of energy micro-cogeneration sistem by natural gas: a study in hjotels three stars

C?mara, Paulo Roberto da 19 May 2006 (has links)
Made available in DSpace on 2014-12-17T14:53:24Z (GMT). No. of bitstreams: 1 PauloRC_principal.pdf: 1483825 bytes, checksum: 47d66773f4b521df5517f6190c35f1be (MD5) Previous issue date: 2006-05-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The natural gas perform a essential paper, not only in primary sectors of energy, but also in others sectors of economy. The use natural gas will have expansion in Brazil, motivated by governmental decision to increase the participation of this fuel in the Brazilian energy matrix from 4% to 12% up until 2010. in order to reach the objective related to increase the consumption of natural gas in the energy matrix and to propose solutions to attend the electric requirements of heart and refrigeration, using natural gas as primary power plant. This thesis has a main objective to analysis the perception of businessmen of hotel sector about the feasability of investment with micro-cogeneration system by natural gas in their hotel in turistic sector, in Natal/RN. It s show a case for the hotels selected analyzing the actual knowledge of businessmen about alternative of new technology in generation of owner energy. There was make a interview using a standard form researching information about this topic. In this interview has shown 4 (four) canaries for businessmen with different configurations of investment in micro-cogeneration. Two of this canaries uses the project finance like option to make fasible this projects. The resulteis showed who businessmen has insecurity to make decision to put in office alone, or with a local company, and perhaps with a national company to perform for a alternative energy system, justifying, the alone feasability and without information by local businessmen. Apart from that, they are receptive for a option to put in office in micro-cogeneration configured in the settings using project finance / O g?s natural desempenha um papel fundamental, n?o s? no setor de energia prim?ria, mas tamb?m em outros setores da economia. Ele ter? forte expans?o no Brasil, motivado pela decis?o do Governo Federal de aumentar a participa??o desse combust?vel na matriz energ?tica de 4% para 12% at? 2010. Para que isso aconte?a ? de suma import?ncia o investimento em novas tecnologias e inclusive o aprimoramento. Afim de um aumento do consumo do g?s natural, na matriz energ?tica, e propor solu??es que atendam aos requisitos el?tricos, na gera??o de calor e refrigera??o, utilizando g?s natural como fonte de energia prim?ria. Este trabalho tem por objetivo principal analisar a atual percep??o dos empres?rios do setor hoteleiro com rela??o ? viabilidade de investimentos com um sistema de microcogera??o a g?s natural em seus hot?is do setor tur?stico, na cidade de Natal/RN. ? apresentado um estudo de caso para os hot?is selecionados, analisando o atual conhecimento dos empres?rios sobre alternativas de novas tecnologias na gera??o de energia pr?pria. Foi realizada uma entrevista com utiliza??o de um question?rio padr?o, buscando as informa??es relevantes sobre o tema. Nesta entrevista foram apresentados 04 (quatro) cen?rios para os empres?rios, onde foram configuradas diferentes op??es de investimentos em microcogera??o. Dois desses cen?rios utilizam o Project finance como op??o de viabilizar o financiamento dos projetos. Os resultados alcan?ados mostram que os empres?rios t?m inseguran?a na tomada de decis?o para investir sozinho, ou em parceria com uma empresa local, e talvez com uma empresa nacional na execu??o de um sistema alternativo de energia, justificando, a inviabilidade isoladaeafalta de vis?o dos empres?rios locais. Em contrapartida se mostraram receptivos a op??o de investimento em micro-cogera??o configurado nos cen?rios utilizando o Project Finance
45

Proposta de integra??o das redes de comunica??o da COSERN como uma solu??o de contig?ncvia em caso de falhas nos enlaces do backbone de automa??o

Oliveira, Bernardo Em?dio Fernandes de 30 July 2004 (has links)
Made available in DSpace on 2014-12-17T14:55:18Z (GMT). No. of bitstreams: 1 BernardoEFO_da_capa_ate_pag_6.pdf: 6543613 bytes, checksum: e29df354784b19e68507e0beca1e614a (MD5) Previous issue date: 2004-07-30 / T'his dissertation proposes alternative models to allow the interconnectioin of the data communication networks of COSERN Companhia Energ?tica do Rio Grande do Norte. These networks comprise the oorporative data network, based on TCP/IP architecture, and the automation system linking remote electric energy distribution substations to the main Operatin Centre, based on digital radio links and using the IEC 60870-5-101 protoco1s. The envisaged interconnection aims to provide automation data originated from substations with a contingent route to the Operation Center, in moments of failure or maintenance of the digital radio links. Among the presented models, the one chosen for development consists of a computational prototype based on a standard personal computer, working under LINUX operational system and running na application, developesd in C language, wich functions as a Gateway between the protocols of the TCP/IP stack and the IEC 60870-5-101 suite. So, it is described this model analysis, implementation and tests of functionality and performance. During the test phase it was basically verified the delay introduced by the TCP/IP network when transporting automation data, in order to guarantee that it was cionsistent with the time periods present on the automation network. Besides , additional modules are suggested to the prototype, in order to handle other issues such as security and prioriz\ation of the automation system data, whenever they are travesing the TCP/IP network. Finally, a study h?s been done aiming to integrate, in more complete way, the two considered networks. It uses IP platform as a solution of convergence to the communication subsystem of na unified network, as the most recente market tendencies for supervisory and other automation systems indicate / Este trabalho prop?e modelos alternativos, capazes de permitir a interliga??o das redes de comunica??o de dados da Companhia Energ?tica do Rio Grande do Norte-COSERN. Essa interliga??o tem por objetivo possibilitar que os dados do sistema de automa??o das subesta??es de distribui??o de energia el?trica, que trafegam em uma rede baseada em enlaces de r?dios digitais e utilizam os protocolos da fam?lia IEC 60870-5-101, possam utilizar a rede corporativa de dados, baseada na arquitetura TCP/IP, como rota de conting?ncia para momentos de falha ou de manunten??o nos enlaces desta rede de automa??o. Dentre os modelos apresentados, escolheu-se para desenvolvimento uma solu??o que consiste de um prot?tipo computacional baseado em um microcomputador pessoal padr?o, com sistema operacional LINUX e aplicativos desenvolvidos em linguagem C, capaz de funcionar como um gateway entre os protocolos da pilha TCP/IP e os protocolos IEC 60870-5-101. O trabalho descreve, ent?o, a an?lise, a implementa??o e os testes de funcionalidade e desempenho deste modelo. Na fase de testes foram verificados, principalmente, os tempos relativos aos atrasos introduzidos pela rede TCP/IP, para assegurar que os mesmos sejam compat?veis com os tempos praticados na rede de automa??o. Al?m disso, s?o sugeridos m?dulos adicionais ao prot?tipo, para tratar de quest?es como seguran?a e prioriza??o dos dados do sistema de automa??o, quando estes trafegampela rede TCP/IP. Finalmente, foi feito um estudo visando uma integra??o mais completa entre as duas redes consideradas, usando a plataforma IP como solu??o de converg?ncia para o subsistema de comunica??o de uma rede unificada, como indica a tend?ncia mais recente no mercado como solu??o para sistemas supervis?rios e outros sistemas de automa??o
46

Controle inteligente de press?o para uma rede sem reservat?rio de abastecimento urbano de ?gua

Oliveira, Jos? Kleber Costa de 04 May 2012 (has links)
Made available in DSpace on 2014-12-17T14:56:01Z (GMT). No. of bitstreams: 1 JoseKCO_DISSERT.pdf: 2360607 bytes, checksum: ad43aaed1b6651cd3d8e3ffe4e2f5b67 (MD5) Previous issue date: 2012-05-04 / The sanitation companies from Brazil has a great challenge for the XXI century: seek to mitigate the rate of physical waste (water, chemicals and electricity) and financial waste caused by inefficient operating systems drinking water supply, considering that currently we already face, in some cases, the scarcity of water resources. The supply systems are increasingly complex as they seek to minimize waste and at the same time better serve the growing number of users. However, this technological change is to reduce the complexity of the challenges posed by the need to include users with higher quality and efficiency in services. A major challenge for companies of water supplies is to provide a good quality service contemplating reducing expenditure on electricity. In this situation we developed a research by a method that seeks to control the pressure of the distribution systems that do not have the tank in your setup and the water comes out of the well directly to the distribution system. The method of pressure control (intelligent control) uses fuzzy logic to eliminate the waste of electricity and the leaks from the production of pumps that inject directly into the distribution system, which causes waste of energy when the consumption of households is reduced causing the saturation of the distribution system. This study was conducted at Green Club II condominium, located in the city of Parnamirim, state of Rio Grande do Norte, in order to study the pressure behavior of the output of the pump that injects water directly into the distribution system. The study was only possible because of the need we had to find a solution to some leaks in the existing distribution system and the extensions of the respective condominium residences, which sparked interest in developing a job in order to carry out the experiments contained in this research / As empresas de saneamento do Brasil t?m um grande desafio para o s?culo XXI, procurar diminuir o ?ndice de desperd?cios f?sicos (?gua, produtos qu?micos e energia el?trica) e financeiros causados pela inefici?ncia operacional dos sistemas de abastecimento de ?gua pot?vel, levando-se em considera??o que atualmente j? se enfrenta, em alguns casos, a escassez dos recursos h?dricos. Os sistemas de abastecimento est?o cada vez mais complexos porque buscam minimizar os desperd?cios e ao mesmo tempo atender melhor ao crescente n?mero de usu?rios. Contudo, a evolu??o tecnol?gica est? presente para diminuir a complexidade dos desafios hora impostos pela necessidade de contemplar os usu?rios com maior qualidade e efici?ncia nos servi?os. Um dos grandes desafios para as empresas de abastecimento de ?gua est? em proporcionar um servi?o de boa qualidade contemplando a diminui??o das despesas com energia el?trica. Diante disso, desenvolveu-se um trabalho de pesquisa atrav?s de um m?todo que busca controlar a press?o da rede de distribui??o em sistemas que n?o apresentam na sua configura??o o reservat?rio e, por isso a ?gua sai do po?o diretamente para a rede de distribui??o. O m?todo de controle da press?o (controle inteligente) utiliza a l?gica fuzzy para eliminar o desperd?cio de energia el?trica e os vazamentos provocados pela produ??o das bombas que injetam diretamente na rede de distribui??o, provocando desperd?cio de energia quando o consumo das resid?ncias ? reduzido causando o saturamento da rede. Esse trabalho foi realizado no condom?nio Green Club II, situado na cidade de Parnamirim - RN, com o objetivo de estudar o comportamento da press?o da bomba que injeta diretamente na rede de distribui??o. O estudo s? foi poss?vel em virtude da necessidade que havia de se encontrar uma solu??o para alguns vazamentos existentes na rede de distribui??o e nos ramais das resid?ncias do respectivo condom?nio, fato que despertou o interesse em desenvolver um trabalho com o intuito de realizar as experi?ncias contidas nesta pesquisa
47

Pain?is-sandu?che com n?cleo de EPS reciclado: metodologia de execu??o e determina??o de propriedades termof?sicas

Silva, George da Cruz 12 April 2010 (has links)
Made available in DSpace on 2014-12-17T14:58:01Z (GMT). No. of bitstreams: 1 GeorgeCS_DISSERT.pdf: 2052095 bytes, checksum: 94bcb92ee6c4f6a8299833c1b6b33205 (MD5) Previous issue date: 2010-04-12 / New materials made from industrial wastes have been studied as an alternative to traditional fabrication processes in building and civil engineering. These materials are produced considering some issues like: cost, efficiency and reduction of nvironmental damage. Specifically in cases of materials destined to dwellings in low latitude regions, like Brazilian Northeast, efficiency is related to mechanical and thermal resistance. Thus, when thermal insulation and energetic efficiency are aimed, it s important to increase thermal resistance without depletion of mechanical properties. This research was conducted on a construction element made of two plates of cement mortar, interspersed with a plate of recycled expanded polystyrene (EPS). This component, widely known as sandwich-panel, is commonly manufactured with commercial EPS whose substitution was proposed in this study. For this purpose it was applied a detailed methodology that defines parameters to a rational batching of the elements that constitute the nucleus. Samples of recycled EPS were made in two different values of apparent specific mass (ρ = 65 kg/m?; ρ = 130 kg/m?) and submitted to the Quick-Line 30TM that is a thermophysical properties analyzer. Based on the results of thermal conductivity, thermal capacity and thermal diffusivity obtained, it was possible to assure that recycled EPS has thermal insulation characteristics that qualify it to replace commercial EPS in building and civil engineering industry / Novos materiais desenvolvidos a partir de res?duos industriais v?m sendo estudados como alternativa aos modelos tradicionalmente empregados na constru??o civil. Para desenvolvimento desses materiais s?o considerados fatores como: custo, efici?ncia e redu??o de passivo ambiental. No caso espec?fico de materiais para aplica??o em habita??es situadas em baixas latitudes, como no Nordeste do Brasil, a efici?ncia diz respeito ?s resist?ncias mec?nica e t?rmica, onde o aumento da resist?ncia t?rmica, sem comprometimento da resist?ncia mec?nica, ? desej?vel quando se buscam a isola??o t?rmica e a efici?ncia energ?tica das edifica??es. No presente trabalho s?o apresentados os resultados do estudo de um elemento construtivo composto de placas de argamassa de cimento intercaladas por placa de EPS reciclado, constituindo um painel sandu?che para emprego na ind?stria da constru??o civil. Estuda-se detalhadamente a metodologia de execu??o desses pain?is, definindo-se par?metros para dosagem racional dos materiais que comp?em o n?cleo. Foram confeccionados corpos de prova com massas espec?ficas aparentes de 65 kg/m? e 130 kg/m?. As propriedades termof?sicas dos corpos de prova foram analisadas utilizando-se o equipamento Quick-Line 30TM, que forneceu dados de condutividade t?rmica, capacidade calor?fica e difusividade t?rmica. Com base nos resultados obtidos foi poss?vel constatar as boas caracter?sticas do EPS reciclado como material termoisolante, estando esse apto ? substitui??o do EPS comercial em pain?is de constru??o
48

Estrat?gias de ventila??o natural e sua influ?ncia na renova??o do ar em uma edifica??o hospitalar: anteprojeto de um novo ambulat?rio para o Hospital Universit?rio Onofre Lopes

Clemente, Fabiano Fechine Torres 31 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-12T20:24:38Z No. of bitstreams: 1 FabianoFechineTorresClemente_DISSERT.pdf: 35056002 bytes, checksum: 41ba19bd8f6d578f57a68b5233e5a621 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-16T20:05:40Z (GMT) No. of bitstreams: 1 FabianoFechineTorresClemente_DISSERT.pdf: 35056002 bytes, checksum: 41ba19bd8f6d578f57a68b5233e5a621 (MD5) / Made available in DSpace on 2018-03-16T20:05:40Z (GMT). No. of bitstreams: 1 FabianoFechineTorresClemente_DISSERT.pdf: 35056002 bytes, checksum: 41ba19bd8f6d578f57a68b5233e5a621 (MD5) Previous issue date: 2017-07-31 / Alguns s?tios na cidade de Natal/RN possuem agrad?veis condi??es de ventila??o natural, no entanto, as edifica??es constru?das dependem excessivamente de sistemas de ar-condicionado para renova??o do ar, muitas vezes fruto de um planejamento inadequado que n?o prioriza aspectos do conforto ambiental. Sendo assim, o trabalho a seguir trata-se do anteprojeto arquitet?nico de um novo ambulat?rio para o Hospital Universit?rio Onofre Lopes com ?nfase na aplica??o de estrat?gias passivas de ventila??o natural com objetivo de promover um maior n?mero de trocas de ar no interior dos ambientes. O pr?dio possui uma ?rea constru?da de 31.998,97m?, distribu?dos ao longo de 10 pavimentos, sendo um t?rreo e mais 06 andares superiores, al?m de tr?s subsolos, a ser edificado na ?rea 01 do Campus Biom?dico da Sa?de, localizado no Bairro de Petr?polis. A ado??o do partido arquitet?nico levou em considera??o uma s?rie de condicionantes tais como topografia do terreno, dire??o e velocidade dos ventos predominantes, sistema construtivo, al?m daquelas de ordem normativas, com destaque para NBR-15220 e C?digo de Combate a Inc?ndio. Os procedimentos metodol?gicos adotados envolveram o c?lculo do fluxo e n?mero de trocas de ar por hora nas salas de espera, consult?rios e mecanoterapia/termoterapia que foram registrados em mem?rias de c?lculo, para o qual foi necess?rio o conhecimento das velocidades dos ventos no interior dos ambientes analisados, de dados obtidos na base de dados do Laborat?rio de Conforto Ambiental da Universidade Federal do Rio Grande do Norte, al?m da utiliza??o de refer?ncias bibliogr?ficas sobre o tema do conforto t?rmico. Os resultados obtidos mostram que as estrat?gias de ventila??o cruzada aplicadas no projeto, tais como utiliza??o de sheds na cobertura para captar o vento em dire??o a po?os de ventila??o, aliados a ?trios internos e loca??o de aberturas em pontos opostos com diferentes coeficientes de press?o, dimensionadas e sombreadas adequadamente, provocam um aumento no fluxo e n?mero de trocas de ar por hora no interior dos ambientes quando comparado ? ventila??o unilateral. Dessa forma permite-se que cada um seja ocupado por uma maior quantidade de pessoas, requisito esse importante para a funcionalidade do pr?dio, j? que o hospital trata-se de uma institui??o de ensino. Dessa forma, potencializa-se o uso da ventila??o natural e cria-se as condi??es para minimizar o consumo de ar condicionado, que contribui para o planejamento de uma arquitetura com mais efici?ncia energ?tica. / Some sites in the city of Natal / RN have pleasant conditions of natural ventilation, however, the built buildings rely heavily on air conditioning systems for air renovation, often the result of inadequate planning that does not prioritize aspects of environmental comfort. Therefore, the following work deals with the architectural design of a new outpatient clinic for the University Hospital Onofre Lopes, with emphasis on the application of passive strategies of natural ventilation with the objective of promoting a greater number of air changes within the environments. The building has a built area of 31,998.97m?, distributed over 10 floors, one ground floor and a further six floors, in addition to three basements, to be built in area 01 of the Biomedical Health Campus, located in the Petropolis District. The adoption of the architectural party took into account a series of constraints such as topography of the terrain, direction and speed of prevailing winds, construction system, besides those of normative order, especially NBR-15220 and Fire Code. The methodological procedures adopted involved calculating the flow and number of air changes per hour in the waiting rooms, clinics and mechanotherapy / thermotherapy that were recorded in calculation memories, for which it was necessary to know the velocities of the winds inside the environments analyzed, from data obtained from the Laboratory of Environmental Comfort of the Federal University of Rio Grande do Norte, in addition to the use of bibliographical references on the topic of thermal comfort. The results show that the cross ventilation strategies applied in the design, such as the use of sheds in the roof to capture the wind towards ventilation wells, allied to internal atria and rent of openings in opposite points with different pressure coefficients, dimensioned and properly shaded, cause an increase in the flow and number of air changes per hour inside the environments when compared to unilateral ventilation. In this way, each one is allowed to be occupied by a larger number of people, a requirement that is important for the functionality of the building, since the hospital is a teaching institution. In this way, the use of natural ventilation is potentiated and conditions are created to minimize the consumption of air conditioning, which contributes to the planning of a more energy efficient architecture.
49

Arquitetura de um cluster computacional de baixo consumo e com proporcionalidade energ?tica

Alves Filho, Sebasti?o Em?dio 01 December 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-20T17:11:47Z No. of bitstreams: 1 SebastiaoEmidioAlvesFilho_TESE.pdf: 1396937 bytes, checksum: 809a90c1177992fb8eec2bff66c2e006 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-22T12:00:56Z (GMT) No. of bitstreams: 1 SebastiaoEmidioAlvesFilho_TESE.pdf: 1396937 bytes, checksum: 809a90c1177992fb8eec2bff66c2e006 (MD5) / Made available in DSpace on 2018-03-22T12:00:56Z (GMT). No. of bitstreams: 1 SebastiaoEmidioAlvesFilho_TESE.pdf: 1396937 bytes, checksum: 809a90c1177992fb8eec2bff66c2e006 (MD5) Previous issue date: 2017-12-01 / Um dos principais desafios da Computa??o Verde ? obter uma melhor rela??o entre a quantidade de trabalho realizada pela infraestrutura computacional e o gasto energ?tico para mant?-la, isto ?, uma melhor efici?ncia energ?tica. Este trabalho apresenta a arquitetura de um cluster computacional de baixo consumo energ?tico que ? capaz de ligar ou desligar, de forma din?mica e autom?tica, um determinado n?mero de m?quinas. A quantidade de m?quinas ligadas ? proporcional ? demanda de trabalho a cada momento, o que evita ligar equipamentos desnecessariamente e aumenta a efici?ncia do sistema. Para o seu desenvolvimento prop?e-se e discute-se um modelo te?rico que ? implementado atrav?s de um cluster composto por dispositivos Raspberry Pi chamado NPi-Cluster. Para atestar a efici?ncia do modelo proposto s?o mostrados resultados experimentais nos quais o cluster ? usado como um servidor web com balanceamento de carga. Os dados obtidos mostram que o NPi-Cluster tem um desempenho adequado quando comparado a outros servidores que rodam em arquiteturas tradicionais, mas com um consumo energ?tico menor. Um cluster com 7 m?quinas usando sua capacidade m?xima atende a mais de 450 requisi??es simult?neas numa taxa de cerca de 1000 transa??es por segundo. Para faz?-lo o cluster consome cerca de 15 Watts, o equivalente a uma l?mpada econ?mica ou um computador em modo suspenso que n?o realiza qualquer atividade. Quando a demanda ? baixa o consumo de energia com as m?quinas ? reduzido dinamicamente, chegando a menos de 2Watts. Al?m de ser capaz de lidar com cargas de trabalhos com boa qualidade de servi?o, o cluster tamb?m prov? alta disponibilidade evitando pontos ?nicos de falha. / One of the main challenges for the so-called Green Computing is to get a better relation between the amount of work performed by the computational infrastructure and the energy consumption to maintain it, providing better energy efficiency. This work presents the architecture of a computing cluster with low energy consumption that powers on or off a number of running machines automatically and dynamically. The quantity of enabled devices adjusts according to the actual processing demand, which avoids unnecessarily powered equipment and increases the overall system power efficiency. In order to carry out its development, a theoretical model is proposed, discussed, and implemented through the NPi-Cluster, a cluster composed of Raspberry Pi devices. To prove the proposed model feasibility, NPi-Cluster is used as a web server with load balancing. Data gathered shows that NPi-Cluster has adequate performance when compared to other web servers running on traditional server architectures, however with less power consumption. A 7-machine cluster running at maximum performance is able to handle more than 450 simultaneous requests, with about 1000 transactions per second. The power consumption required to do it is about 15 Watts, which is equivalent to a energy-saving light bulb or a computer in suspended mode that does not perform any task. When the requests demand is low, the power consumption is dynamically reduced until less than 2 Watts. Besides to being able to handle workloads with acceptable quality of service, the proposed cluster also provides high availability by avoiding single points of failure.
50

Nanoestruturas magn?ticas do tipo n?cleo-casca: um estudo do impacto do campo dipolar / Core-shell magnetic nanostructure: a study of impact of dipolar field

Oliveira, Leonardo Linhares 23 June 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T19:50:48Z No. of bitstreams: 1 LeonardoLinharesOliveira_TESE.pdf: 68488662 bytes, checksum: de2543920cd8d7f953cc8b1b5d1ebf66 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-13T19:10:14Z (GMT) No. of bitstreams: 1 LeonardoLinharesOliveira_TESE.pdf: 68488662 bytes, checksum: de2543920cd8d7f953cc8b1b5d1ebf66 (MD5) / Made available in DSpace on 2017-03-13T19:10:14Z (GMT). No. of bitstreams: 1 LeonardoLinharesOliveira_TESE.pdf: 68488662 bytes, checksum: de2543920cd8d7f953cc8b1b5d1ebf66 (MD5) Previous issue date: 2016-06-23 / Nanopart?culas bi-magn?ticas t?m se mostrado promissores em v?rias aplica??es tecnol?gicas, tais como produ??o de ?m?s permanentes, desenvolvimento de geradores de micro-ondas, nano osciladores e sistemas para grava??o magn?tica. Apresentamos um estudo te?rico acerca de nanoestruturas bimagn?ticas do tipo n?cleo@casca constitu?da de materiais ferromagn?ticos de alta e baixa anisotropia. O presente trabalho analisou nanopart?culas com geometria esf?rica e cil?ndrica. Part?culas com formato esf?rico pode ser empregada como pe?a fundamental na constru??o de im?s permanentes de alto desempenho, pois podem apresentar melhorias expressivas no produto energ?tico m?ximo, (BH)max, do sistema. O (BH)max ? um par?metro chave, pois determina se um material ? considerado bom para im? permanente. Nossos resultados mostram que o (BH)max pode ser melhorado significativamente, uma part?cula SmCo5 com 3,5 nm de di?metro recoberta por uma casca de Ferro de 2,5 nm de espessura pode apresentar (BH)max cerca de 4 vezes maior que a part?cula n?o recoberta. No entanto, para um n?cleo de mesmo material, com di?metro muito superior e cascas de Ferro relativamente espessas h? uma redu??o do (BH)max que inviabiliza seu uso para a fabrica??o de ?m?s permanentes. Discutiremos nesse trabalho o comportamento do produto energ?tico destes sistemas. Nanoestruturas com geometria cil?ndrica apresentam diversas aplica??es, como nano osciladores e mem?rias magn?ticas. Dessa forma, conhecer o perfil magn?tico e o comportamento da magnetiza??o no processo de desmagnetiza??o ? de grande relev?ncia. Um cilindro de Permalloy pode com di?metro de 57,0 nm e altura de 21,0 nm apresentar ao longo de sua curva de magnetiza??o o estado v?rtice. A inibi??o deste estado ? relevante para algumas aplica??es e pode ser alcan?ada com a presen?a de um anel externo de um material com momento magn?tico elevado. Do mesmo modo, pode apresentar v?rtice na curva de magnetiza??o devido a presen?a do anel magn?tico. Estudamos ainda os estados magn?ticos presentes em an?is devido a intera??o magn?tica dipolar com o n?cleo. / Bi-magnetic anoparticles has been shown promises in several tachnological applications, such that permanent magnets, microwave generators devices, nanooscilators and magnetic record system for example. We presents a theoretical study about bi-magnetic core@shell nanoparticles consisting of high and low anisotropy ferromagnetic materials. The present work has analyzed nanoparticles with spherical and cylindrical geometries. Spherical particles can be employed as building block for high performance magnets, because can presents a expensive improvement in high energy product, (BH)max, of the system. The (BH)max is a key parameter, because it?s indicate if a material is good to permanent magnets. Our results show that (BH)maxcan be improved significantly, a particle of SmCo5 with 3.5 nm recovered by iron shell with 2.5 nm thickness can presents (BH)max thereabout 4 times great then uncovered particle. In other way, a core of the same material, with major diameter s relative thick shell there is a reduction in (BH)max that unfeasible their use in production of permanent magnets. We discuss in the present work the behavior of energy product these systems. Nanostructures with cylindrical geometries presents several applications, such that nano-oscillators and magnetic memory. In this way, know the magnetic profile and behavior of magnetization in demagnetizing process is relevant. A permalloy cylinder can, with 57.0 nm diameter and 21.0 nm height, presents along your magnetization curve, a vortex state. The inhibition of this state is relevant for some applications and can be reached with a presence of an external ring with elevated magnetic moment material. In the same way, can present vortex in magnetization curve by magnetic ring presence. We study further the magnetic states existing in magnetic ring due to magnetic dipolar interaction with a core.

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