Made available in DSpace on 2015-03-13T17:10:49Z (GMT). No. of bitstreams: 1 FabianaMM_DISSERT.pdf: 4388914 bytes, checksum: 14a7e7684ec0454798a3e3f4641314b9 (MD5) Previous issue date: 2013-03-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aims to conduct an analysis on the production of space and the dynamics between social agents that act and interact, albeit in different ways, in the production and re-production space in the Neighborhood Potengi in Natal, Rio Grande do Norte. The neighborhood is undergoing a process of dynamism undeniable and has a daily marked by heterogeneity, especially as a neighborhood in transition. So your analysis, from the perspective of the dialectical method, contributes to the understanding of the production space can be analyzed through the study of the forms and content, and may contribute to its real apprehension. After all, the city reflects forms, assumes functions, features and content that dynamic influences and is influenced by human relationships. Thus, this research seeks to analyze the production of space, based on the observation and study of the rich daily life of different social agents that operate within concrete quoted / Este trabalho objetiva realizar uma an?lise sobre a produ??o do espa?o e a din?mica existente entre os agentes sociais que atuam e interagem, embora de maneiras distintas, na produ??o e re-produ??o espacial no Bairro Potengi em Natal, Rio Grande do Norte. O bairro vive um processo de dinamismo incontest?vel e possui um cotidiano marcado pela heterogeneidade, destacando-se como um bairro em transi??o. Portanto, sua an?lise, sob a perspectiva do m?todo dial?tico, contribui para a compreens?o de que a produ??o espacial pode ser analisada atrav?s do estudo das formas e dos conte?dos, podendo contribuir para a sua real apreens?o. Afinal, a cidade reflete formas, assume fun??es, apresenta conte?dos e essa din?mica influi e ? influenciada pelas rela??es humanas. Assim, esta pesquisa busca analisar a produ??o do espa?o, com base na observa??o e no estudo do rico cotidiano dos distintos agentes sociais concretos que atuam no espa?o citado

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-12-02T22:57:03Z No. of bitstreams: 1 YuriShalomDeFreitasBezerra_DISSERT.pdf: 1870636 bytes, checksum: fa87a782197886fe563d90143a5c4a3a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2015-12-09T20:15:23Z (GMT) No. of bitstreams: 1 YuriShalomDeFreitasBezerra_DISSERT.pdf: 1870636 bytes, checksum: fa87a782197886fe563d90143a5c4a3a (MD5) / Made available in DSpace on 2015-12-09T20:15:23Z (GMT). No. of bitstreams: 1 YuriShalomDeFreitasBezerra_DISSERT.pdf: 1870636 bytes, checksum: fa87a782197886fe563d90143a5c4a3a (MD5) Previous issue date: 2014-08-30 / O m?todo de Monte Carlo ? preciso e, quando comparado com outras t?cnicas num?ricas, ? de relativamente f?cil implementa??o para a solu??o de problemas envolvendo geometrias complexas e espalhamento anisotr?pico da radia??o. Al?m disso, diferentemente do que ocorre para a maioria das t?cnicas num?ricas, cujo tempo necess?rio para a execu??o de simula??es tende a crescer exponencialmente ? medida que a complexidade do problema aumenta, no Monte Carlo, o aumento no tempo computacional tende a ser linear. Ainda assim, as solu??es em Monte Carlo s?o computacionalmente pesadas para a solu??o da maioria dos problemas de interesse. O modelo dos Pacotes de Energia Multiespectrais permite a redu??o dos tempos computacionais associados ?s solu??es atrav?s do m?todo de Monte Carlo. O modelo ? aqui analisado para aplica??es em meios constitu?dos por esp?cies n?o-participantes e vapor d??gua, que ? um importante emissor de radia??o formado na combust?o de hidrocarbonetos. Aspectos relacionados ? otimiza??o dos tempos computacionais s?o investigados e solu??es obtidas com o modelo s?o comparadas com solu??es linha-por-linha benchmark. / The Monte Carlo method is accurate and is relatively simple to implement for the solution of problems involving complex geometries and anisotropic scattering of radiation as compared with other numerical techniques. In addition, differently of what happens for most of numerical techniques, for which the associated simulations computational time tends to increase exponentially with the complexity of the problems, in the Monte Carlo the increase of the computational time tends to be linear. Nevertheless, the Monte Carlo solution is highly computer time consuming for most of the interest problems. The Multispectral Energy Bundle model allows the reduction of the computational time associated to the Monte Carlo solution. The referred model is here analyzed for applications in media constituted for nonparticipating species and water vapor, which is an important emitting species formed during the combustion of hydrocarbon fuels. Aspects related to computer time optimization are investigated the model solutions are compared with benchmark line-by-line solutions

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-03T20:29:00Z No. of bitstreams: 1 DiegoSilveiraCostaNascimento_TESE.pdf: 3953454 bytes, checksum: 3237fa5d0296298ccc738a2ba7eab05e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-03T23:54:37Z (GMT) No. of bitstreams: 1 DiegoSilveiraCostaNascimento_TESE.pdf: 3953454 bytes, checksum: 3237fa5d0296298ccc738a2ba7eab05e (MD5) / Made available in DSpace on 2016-02-03T23:54:37Z (GMT). No. of bitstreams: 1 DiegoSilveiraCostaNascimento_TESE.pdf: 3953454 bytes, checksum: 3237fa5d0296298ccc738a2ba7eab05e (MD5) Previous issue date: 2014-12-05 / Significativos avan?os v?m surgindo em pesquisas relacionadas ao tema de Comit?s de Classificadores. Os modelos que mais recebem aten??o na literatura s?o aqueles de natureza est?tica, ou tamb?m conhecidos por ensembles. Dos algoritmos que fazem parte dessa classe, destacam-se os m?todos que utilizam reamostragem dos dados de treinamento: Bagging, Boosting e Multiboosting. A escolha do tipo de arquitetura e dos componentes a serem recrutados n?o ? uma tarefa trivial, e tem motivado, ainda mais, o surgimento de novas propostas na tentativa de se construir tais modelos de forma autom?tica e, muitas delas, s?o baseadas em m?todos de otimiza??o. Muitas dessas contribui??es n?o t?m apresentado resultados satisfat?rios quando aplicadas a problemas mais complexos ou de natureza distinta. Em contrapartida, a tese aqui apresentada prop?e tr?s novas abordagens h?bridas para constru??o autom?tica em ensembles de classificadores: Incremento de Diversidade, Fun??o de Avalia??o Adaptativa e Meta-aprendizado para a elabora??o de sistemas de configura??o autom?tica dos par?metros de controle para os modelos de ensemble. Na primeira abordagem, ? proposta uma solu??o que combina diferentes t?cnicas de diversidade em um ?nico arcabou?o conceitual, na tentativa de se alcan?ar n?veis mais elevados de diversidade em ensemble, e com isso, melhor o desempenho de tais sistemas. J? na segunda abordagem, ? utilizado um algoritmo gen?tico para o design autom?tico de ensembles. A contribui??o consiste em combinar as t?cnicas de filtro e wrapper de forma adaptativa para evoluir uma melhor distribui??o do espa?o de atributos a serem apresentados aos componentes de um ensemble. E por fim, a ?ltima abordagem, que prop?e uma nova t?cnica de recomenda??o de arquitetura e componentes base em ensemble, via t?cnicas de meta-aprendizado tradicional e multirr?tulo. De forma geral os resultados s?o animadores, e corroboram com a tese de que ferramentas h?bridas s?o uma poderosa solu??o na constru??o de ensembles eficazes em problemas de classifica??o de padr?es / Significant advances have emerged in research related to the topic of Classifier Committees. The models that receive the most attention in the literature are those of the static nature, also known as ensembles. The algorithms that are part of this class, we highlight the methods that using techniques of resampling of the training data: Bagging, Boosting and Multiboosting. The choice of the architecture and base components to be recruited is not a trivial task and has motivated new proposals in an attempt to build such models automatically, and many of them are based on optimization methods. Many of these contributions have not shown satisfactory results when applied to more complex problems with different nature. In contrast, the thesis presented here, proposes three new hybrid approaches for automatic construction for ensembles: Increment of Diversity, Adaptive-fitness Function and Meta-learning for the development of systems for automatic configuration of parameters for models of ensemble. In the first one approach, we propose a solution that combines different diversity techniques in a single conceptual framework, in attempt to achieve higher levels of diversity in ensembles, and with it, the better the performance of such systems. In the second one approach, using a genetic algorithm for automatic design of ensembles. The contribution is to combine the techniques of filter and wrapper adaptively to evolve a better distribution of the feature space to be presented for the components of ensemble. Finally, the last one approach, which proposes new techniques for recommendation of architecture and based components on ensemble, by techniques of traditional meta-learning and multi-label meta-learning. In general, the results are encouraging and corroborate with the thesis that hybrid tools are a powerful solution in building effective ensembles for pattern classification problems.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-22T00:29:29Z No. of bitstreams: 1 RosanaMariaDoNascimento_TESE.pdf: 79491407 bytes, checksum: 65543c87c5a9f10fd3119a3ddf108730 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-22T23:55:31Z (GMT) No. of bitstreams: 1 RosanaMariaDoNascimento_TESE.pdf: 79491407 bytes, checksum: 65543c87c5a9f10fd3119a3ddf108730 (MD5) / Made available in DSpace on 2016-03-22T23:55:31Z (GMT). No. of bitstreams: 1 RosanaMariaDoNascimento_TESE.pdf: 79491407 bytes, checksum: 65543c87c5a9f10fd3119a3ddf108730 (MD5) Previous issue date: 2015-01-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / A Prov?ncia Borborema, localizada no nordeste do Brasil, possui um embasamento de idade Pr?-cambriana e um arcabou?o tect?nico estruturado no Neoproteroz?ico (740-560 Ma). Ap?s a separa??o dos continentes Sul-Americano e Africano, durante o Mesoz?ico formou-se um sistema de riftes no nordeste brasileiro, o qual deu origem ?s bacias marginais e interiores localizadas na Prov?ncia. Depois da separa??o continental, eventos de vulcanismos e epirogenia ocorreram na Prov?ncia, tais como o soerguimento do Planalto da Borborema e o magmatismo ao longo da linha Macau-Queimadas (AMQ), marcando assim a evolu??o da Prov?ncia. As causas do soerguimento do Planalto poderiam estar associadas a um underplating magm?tico (material m?fico preso na base da crosta), talvez relacionado com a gera??o de plugs continentais jovens (45-7 Ma) ao longo do AMQ devido a um mecanismo de convec??o em pequena escala na borda do continente. O objetivo deste trabalho ? investigar as causas do soerguimento intra-placa e sua poss?vel rela??o com o vulcanismo AMQ utilizando sismologia de banda larga, tendo em conta a correla??o de nossos resultados com estudos geof?sicos e geol?gicos realizados na Prov?ncia Borborema. As metodologias de banda larga para investigar a estrutura profunda na Prov?ncia incluem as fun??es do receptor e velocidade de dispers?o das ondas de superf?cie. Tanto as fun??es de receptor quanto a tomografia de dispers?o de ondas superficiais s?o m?todos que utilizam eventos teless?smicos e permitem obter estimativas de par?metros estruturais como espessura crustal, raz?o Vp/Vs e velocidade de onda S. Os sismogramas utilizados neste trabalho para as fun??es do receptor foram obtidas de 52 esta??es localizadas no Nordeste do Brasil: 16 esta??es de banda larga da rede RSISNE (Rede Sismogr?fica do Nordeste do Brasil), 21 esta??es de per?odo curto da rede INCT-ET (Instituto Nacional de Ci?ncia e Tecnologia ? Estudos Tect?nicos) e 6 esta??es de banda larga. Estes resultados acrescentam significativamente dados anteriores coletados em esta??es isoladas como a esta??o RCBR, da rede global GSN, as esta??es banda v larga CAUB e AGBL do projeto BLSP (Brazilian Lithosphere Seismic Project IAG/USP) e de 6 esta??es banda larga do projeto Mil?nio (Estudos geof?sicos e tect?nicos na Prov?ncia Borborema - CNPq). Para dispers?o de ondas de superf?cie foram usados sismogramas de 22 esta??es: 16 esta??es de banda larga da rede RSISNE, bem como das 6 esta??es banda larga do projeto Mil?nio. Neste trabalho foram desenvolvidas: (i) estimativas de espessura crustal e raz?o Vp/Vs para cada esta??o usando as fun??es do receptor, (ii) novas medidas de velocidade de grupo de ondas de superf?cie, que foram integradas com os percursos usados em uma tomografia da Am?rica do Sul, j? desenvolvida, para ampliar a resolu??o no Nordeste Brasileiro e (iii) modelos de velocidades de onda S (1D) para v?rios locais na Prov?ncia Borborema usando a invers?o simult?nea de fun??es do receptor com velocidades de dispers?o. Os resultados descrevem velocidades de onda S para a base da crosta que s?o consistentes com a presen?a de uma camada m?fica de 5-7.5 km de espessura. Foi observada a camada m?fica em apenas uma por??o da regi?o do planalto (parte sul) e aus?ncia da mesma na parte norte. Outra observa??o importante e que corrobora estudos de fun??es do receptor e refra??o s?smica s?o as diferentes espessuras crustais, tamb?m dividindo o planalto em uma parte de crosta fina (parte norte) e outra parte de crosta espessa (parte sul). Os modelos existentes para evidenciar a epirogenia n?o conseguem explicar todas essas observa??es. Sendo assim, prop?e-se que durante a orogenia Brasiliana, uma camada de material m?fico pr?-existente foi delaminada, total ou parcialmente, da crosta. A delamina??o parcial teria acontecido na parte sul do planalto, onde estudos independentes evidenciaram uma reologia mais resistente ? deforma??o. Ap?s isso, durante o Mesoz?ico e consequente processo de rifteamento houve afinamento da crosta da regi?o costeira e depress?o sertaneja, incluindo a parte norte do planalto. J? no Cenoz?ico, o soerguimento da parte norte do planalto teria ocorrido e o resultado seria uma parte norte sem material m?fico na base da crosta e parte sul com camada m?fica parcialmente delaminada,mas ambos com topografia elevada at? os dias atuais. / The Borborema Province, located in northeastern Brazil, has a basement of Precambrian age and a tectonic framework structured at the Neoproterozoic (740-560 Ma). After separation between South America and Africa during the Mesozoic, a rift system was formed, giving rise to a number of marginal and inland basins in the Province. After continental breakup, episodes of volcanism and uplift characterized the evolution of the Province. Plateau uplift was initially related to magmatic underplating of mafic material at the base of the crust, perhaps related to the generation of young continental plugs (45-7 Ma) along the Macau-Queimadas Alignment (MQA), due to a small-scale convection at the continental edge. The goal of this study is to investigate the causes of intra-plate uplift and its relationship to MQA volcanism, by using broadband seismology and integrating our results with independent geophysical and geological studies in the Borborema Province. The investigation of the deep structure of the Province with broadband seismic data includes receiver functions and surface-wave dispersion tomography. Both the receiver functions and surface-wave dispersion tomography are methods that use teleseismic events and allow to develop estimates of crustal parameters such as crustal thickness, Vp/Vs ratio, and S-velocity structure. The seismograms used for the receiver function work were obtained from 52 stations in Northeast Brazil: 16 broadband stations from the RSISNE network (Rede Sismogr?fica do Nordeste do Brasil), and 21 short-period and 6 broadband stations from the INCT-ET network (Instituto Nacional de Ci?ncia e Tecnologia ? Estudos Tect?nicos). These results add signifi- cantly to previous datasets collected at individual stations in the Province, which include station RCBR (GSN - Global Seismic Network), stations CAUB and AGBL (Brazilian Lithosphere Seismic Project IAG/USP), and 6 other broadband stations that were part of the Projeto Mil?nio - Estudos geof?sicos e tect?nicos na Prov?ncia Borborema/CNPq. For the surface-wave vii tomography, seismograms recorde at 22 broadband stations were utilized: 16 broadband stations from the RSISNE network and 6 broadband stations from the Mil?nio project. The new constraints developed in this work include: (i) estimates of crustal thickness and bulk Vp/Vs ratio for each station using receiver functions; (ii) new measurements of surfassewave group velocity, which were integrated to existing measurementes from a continental-scale tomography for South America, and (iii) S-wave velocity models (1D) at various locations in the Borborema Province, developed through the simultaneous inversion of receiver functions and surface-wave dispersion velocities. The results display S-wave velocity structure down to the base of the crust that are consistent with the presence of a 5-7.5 km thick mafic layer. The mafic layer was observed only in the southern portion of the Plateau and absent in its northern portion. Another important observation is that our models divide the plateau into a region of thin crust (northern Plateau) and a region of thick crust (southern Plateau), confirming results from independent refraction surveys and receiver function analyses. Existing models of plateau uplift, nonetheless, cannot explain all the new observations. It is proposed that during the Brazilian orogeny a layer of preexisting mafic material was delaminated, as a whole or in part, from the original Brasiliano crust. Partial delamination would have happened in the southern portion of the plateau, where independent studies found evidence of a more resistant rheology. During Mesozoic rifting, thinning of the crust around the southern Plateau would have formed the marginal basins and the Sertaneja depression, which would have included the northern part of the Plateau. In the Cenozoic, uplift of the northern Plateau would have occurred, resulting in a northern Plateau without mafic material at the base of the crust and a southern Plateau with partially delaminated mafic layer.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-23T00:13:57Z No. of bitstreams: 1 RodrigoSantosMagalhaes_DISSERT.pdf: 1447888 bytes, checksum: e70ec6719dcc298445d63da7105699d0 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-25T20:21:10Z (GMT) No. of bitstreams: 1 RodrigoSantosMagalhaes_DISSERT.pdf: 1447888 bytes, checksum: e70ec6719dcc298445d63da7105699d0 (MD5) / Made available in DSpace on 2016-04-25T20:21:10Z (GMT). No. of bitstreams: 1 RodrigoSantosMagalhaes_DISSERT.pdf: 1447888 bytes, checksum: e70ec6719dcc298445d63da7105699d0 (MD5) Previous issue date: 2015-04-01 / Este trabalho analisa textos de duas vers?es distintas da B?blia da vertente protestante, a saber: a Almeida, Revista e Corrigida (ARC) e a Nova Tradu??o na Linguagem de Hoje (NTLH). Nesse sentido, investiga as configura??es lingu?stico-textuais dessas vers?es, com o objetivo de identificar diferen?as consider?veis entre elas e implica??es na atribui??o de sentido de uma e de outra. A B?blia ? um livro com influ?ncia hist?rica e sua import?ncia n?o se limita somente ? esfera religiosa, sendo tamb?m considerada, por muitos, como uma obra de alto valor liter?rio. Ela continua em plena e ampla circula??o no contexto hist?rico-religioso-cultural do mundo de hoje. Al?m disso, esse livro re?ne aspectos discursivos e lingu?stico-textuais importantes a serem investigados, especialmente, se considerado o fato de podermos confrontar suas diferentes tradu??es. Das duas vers?es b?blicas (ARC e NTLH), interessam-nos particularmente tr?s g?neros discursivos distintos (poema, par?bola e ep?stola), sendo cinco textos de cada vers?o, o que resulta num total de dez textos. A esse respeito, consideramos, ainda, as variadas sequ?ncias tipol?gicas envolvidas na organiza??o dos g?neros discursivos selecionados, observando se a predomin?ncia de uma dessas sequ?ncias implica maior ou menor facilidade/dificuldade de compreens?o. Utilizamos, tamb?m, como suporte de an?lise, protocolos de leitura de informantes diversificados, levando em considera??o o credo religioso, o grau de escolaridade e a faixa et?ria, a fim de verificar se as diferen?as formais dos textos escolhidos e o perfil social dos leitores motivam poss?veis altera??es no processo de compreens?o textual. Para a realiza??o da an?lise, tomamos como suporte te?rico-metodol?gico a Lingu?stica Funcional Centrada no Uso (ou Lingu?stica Cognitivo-Funcional), a qual aglutina contribui??es da tradi??o funcionalista norte-americana e da Lingu?stica Cognitiva. / This paper analyses the texts of two distinct versions of the protestant Bible, namely: Almeida, Revista e Corrigida (ARC) and Nova Tradu??o na Linguagem de Hoje (NTLH). In this sense, it investigates the linguistic-textual configurations of such versions with the aim of identifying relevant differences between them and the implications for attribution of meaning between the first and the latter. The Bible is a book of historic influence and its importance is not limited only to the religious realm, but is also considered by many as a work of high literary value. It currently remains in full and wide circulation in the historic, religious and cultural contexts. Furthermore, this book gathers important discursive and textual-linguistic aspects worthy of investigation, especially, if the fact of contrasting its different versions is considered. From the two biblical versions (ARC and NTLH), three distinct discursive genres are of interest (poem, parable and epistle), with five texts from each version, resulting in a total of ten texts. In this sense, we are also interested in the various typological sequences involved in the organization of the discursive genres selected, observing if the predominance of such sequences implies in greater or lesser facility/difficulty of comprehension. We also utilized as a support for analysis the reading protocols of diverse informants, taking into consideration the religious beliefs, the level of education and age, with an aim to verify if the formal differences of the selected texts and the social profile of readers could cause possible changes to the process of text comprehension. To carry out the analysis, we used Usage-Based Linguistics (or Cognitive-Functional Linguistics) as a theoreticalmethodological support, which encompasses contributions from the North American functional tradition and cognitive linguistics.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-09T22:51:26Z No. of bitstreams: 1 GilmaraLinharesDeAraujo_TESE.pdf: 11647948 bytes, checksum: 94a5e966f18f8dd6bfc6646d2519542b (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-10T23:44:37Z (GMT) No. of bitstreams: 1 GilmaraLinharesDeAraujo_TESE.pdf: 11647948 bytes, checksum: 94a5e966f18f8dd6bfc6646d2519542b (MD5) / Made available in DSpace on 2016-08-10T23:44:37Z (GMT). No. of bitstreams: 1 GilmaraLinharesDeAraujo_TESE.pdf: 11647948 bytes, checksum: 94a5e966f18f8dd6bfc6646d2519542b (MD5) Previous issue date: 2015-12-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Esse trabalho apresenta uma t?cnica h?brida de projeto de superf?cies seletivas em frequ?ncia, sobre uma camada diel?trica isotr?pica, considerando diversas geometrias para os elementos das c?lulas unit?rias. Especificamente, a t?cnica h?brida usa o m?todo do circuito equivalente em conjunto com algoritmos gen?ticos, visando a s?ntese de estruturas com resposta singleband e dual-band. O m?todo do circuito equivalente permite modelar a estrutura por meio de um circuito equivalente e tamb?m a obten??o de circuitos para diferentes geometrias. A partir da obten??o dos par?metros desses circuitos, podem-se obter as caracter?sticas de transmiss?o e de reflex?o das estruturas modeladas. Para obter a otimiza??o das estruturas modeladas, de acordo com a resposta em frequ?ncia desejada, a ferramenta de otimiza??o do Matlab optimtool mostrou-se de f?cil utiliza??o, permitindo explorar resultados importantes na an?lise de otimiza??o. No trabalho, s?o apresentados resultados num?ricos e experimentais para as caracter?sticas de transmiss?o de diferentes geometrias analisadas. Foram efetuadas compara??es com resultados apresentados na literatura, tendo-se observado uma boaconcord?ncia nos casos analisados para estruturas com substratos isotr?picos. / This thesis presents a hybrid technique of frequency selective surfaces project (FSS) on a isotropic dielectric layer, considering various geometries for the elements of the unit cell. Specifically, the hybrid technique uses the equivalent circuit method in conjunction with genetic algorithm, aiming at the synthesis of structures with response single-band and dual-band. The equivalent circuit method allows you to model the structure by using an equivalent circuit and also obtaining circuits for different geometries. From the obtaining of the parameters of these circuits, you can get the transmission and reflection characteristics of patterned structures. For the optimization of patterned structures, according to the desired frequency response, Matlab? optimization tool named optimtool proved to be easy to use, allowing you to explore important results on the optimization analysis. In this thesis, numeric and experimental results are presented for the different characteristics of the analyzed geometries. For this, it was determined a technique to obtain the parameter N, which is based on genetic algorithms and differential geometry, to obtain the algebraic rational models that determine values of N more accurate, facilitating new projects of FSS with these geometries. The optimal results of N are grouped according to the occupancy factor of the cell and the thickness of the dielectric, for modeling of the structures by means of rational algebraic equations. Furthermore, for the proposed hybrid model was developed a fitness function for the purpose of calculating the error occurred in the definitions of FSS bandwidths with transmission features single band and dual band. This thesis deals with the construction of prototypes of FSS with frequency settings and band widths obtained with the use of this function. The FSS were initially reviewed through simulations performed with the commercial software Ansoft Designer ?, followed by simulation with the equivalent circuit method for obtaining a value of N in order to converge the resonance frequency and the bandwidth of the FSS analyzed, then the results obtained were compared. The methodology applied is validated with the construction and measurement of prototypes with different geometries of the cells of the arrays of FSS.

Made available in DSpace on 2014-12-17T14:55:44Z (GMT). No. of bitstreams: 1 AllanDGA_DISSERT.pdf: 1992696 bytes, checksum: 87d8b1dbc6fe4df6df2f85f90481f9be (MD5) Previous issue date: 2010-01-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study aims to seek a more viable alternative for the calculation of differences in images of stereo vision, using a factor that reduces heel the amount of points that are considered on the captured image, and a network neural-based radial basis functions to interpolate the results. The objective to be achieved is to produce an approximate picture of disparities using algorithms with low computational cost, unlike the classical algorithms / O presente trabalho visa buscar uma alternativa mais vi?vel para o c?lculo das disparidades em imagens de vis?o est?reo, utilizando um fator de salto que reduz a quantidade de pontos que s?o considerados da imagem capturada, e uma rede neural baseada em fun??es de base radial para interpolar os resultados obtidos. O objetivo a ser alcan?ado ? produzir uma imagem de disparidades aproximada da real com algoritmos de baixo custo computacional, diferentemente dos algoritmos tradicionais

Made available in DSpace on 2014-12-17T14:55:44Z (GMT). No. of bitstreams: 1 JoilsonBAR_DISSERT.pdf: 5903616 bytes, checksum: bee0d51eb1c54833e1d9a19364c80c76 (MD5) Previous issue date: 2010-07-30 / The present work describes the use of a mathematical tool to solve problems arising from control theory, including the identification, analysis of the phase portrait and stability, as well as the temporal evolution of the plant s current induction motor. The system identification is an area of mathematical modeling that has as its objective the study of techniques which can determine a dynamic model in representing a real system. The tool used in the identification and analysis of nonlinear dynamical system is the Radial Basis Function (RBF). The process or plant that is used has a mathematical model unknown, but belongs to a particular class that contains an internal dynamics that can be modeled.Will be presented as contributions to the analysis of asymptotic stability of the RBF. The identification using radial basis function is demonstrated through computer simulations from a real data set obtained from the plant / O presente trabalho descreve a utiliza??o de uma ferramenta matem?tica na solu??o de problemas decorrentes da teoria de controle, incluindo a identifica??o, a an?lise do retrato de fase e a estabilidade, bem como a evolu??o temporal da planta de corrente do motor de indu??o. A identifica??o de sistemas ? uma ?rea da modelagem matem?tica que tem como objetivo o estudo de t?cnicas que possam determinar um modelo din?mico na representa??o de um sistema real. A ferramenta utilizada na identifica??o e an?lise do sistema din?mico n?o linear ser? as Fun??es de Base Radial (RBF). O processo ou a planta que ser? utilizada possui um modelo matem?tico desconhecido, mas pertence a uma determinada classe que cont?m uma din?mica interna que pode ser modelada. Ser? apresentada como contribui??es a an?lise da estabilidade assint?tica da RBF. A identifica??o utilizando Fun??es de Base Radial ? demonstrada atrav?s de simula??es computacionais a partir de um conjunto de dados reais obtidos da planta de corrente do motor de indu??o

Made available in DSpace on 2014-12-17T14:55:58Z (GMT). No. of bitstreams: 1 PauloFB.pdf: 617080 bytes, checksum: 5f9c06266e137d13c8b810163ede788d (MD5) Previous issue date: 2005-08-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Microstrip antennas are widely used in modern telecommunication systems. This is particularly due to the great variety of geometries and because they are easily built and integrated to other high frequency devices and circuits. This work presents a study of the properties of the microstrip antenna with an aperture impressed in the conducting patch. Besides, the analysis is performed for isotropic and anisotropic dielectric substrates. The Multiport Network Model MNM is used in combination with the Segmentation Method and the Greens function technique in the analysis of the considered microstrip antenna geometries. The numerical analysis is performed by using the boundary value problem solution, by considering separately the impedance matrix of the structure segments. The analysis for the complete structure is implemented by choosing properly the number and location of the neighboor element ports. The numerial analysis is performed for the following antenna geometries: resonant cavity, microstrip rectangular patch antenna, and microstrip rectangular patch antenna with aperture. The analysis is firstly developed for microstrip antennas on isotropic substrates, and then extended to the case of microstrip antennas on anisotropic substrates by using a Mapping Method. The experimental work is described and related to the development of several prototypes of rectangular microstrip patch antennas wtih and without rectangular apertures. A good agreement was observed between the simulated and measured results. Thereafter, a good agreement was also observed between the results of this work and those shown in literature for microstrip antennas on isotropic substrates. Furthermore, results are proposed for rectangular microstrip patch antennas wtih rectangular apertures in the conducting patch / As antenas de microfita s?o estruturas muito utilizadas nos sistemas de telecomunica??es atuais. Isto decorre, principalmente, da diversidade de configura??es e da facilidade de constru??o e integra??o dessas antenas com outros dispositivos e circuitos de altas freq??ncias. Neste trabalho, o m?todo de an?lise empregado ? o Modelo de Circuito de M?lti-Porta (Multiport Network Model MNM), que combinado com o M?todo da Segmenta??o e a t?cnica da Fun??o de Green, mostra-se adequado ao estudo da antena de microfita com abertura no patch condutor. A partir do equacionamento do problema do valor de contorno, ? ent?o realizada uma an?lise num?rica que consiste em avaliar a estrutura da antena considerada a partir da integra??o dos elementos em que ela foi dividida. Nessa an?lise, os elementos s?o representados por matrizes de imped?ncia e a integra??o ? implementada atrav?s de portas de circuitos adequadamente escolhidas em n?mero e posicionamento. Na an?lise num?rica, foram consideradas as seguintes estruturas: a cavidade ressonante, a microfita com patch retangular convencional (sem abertura) e a microfita com patch retangular com abertura. A an?lise foi efetuada para substratos isotr?picos e estendida para o caso de antenas com substratos anisotr?picos uniaxiais atrav?s do M?todo do Mapeamento. S?o apresentados resultados para a freq??ncia de resson?ncia e para a imped?ncia de entrada de antenas de microfita. A parte experimental do trabalho consistiu no projeto, constru??o e medi??o de v?rios prot?tipos de antenas de microfita com patches retangulares com e sem abertura. Observou-se que os resultados obtidos, atrav?s da simula??o num?rica, apresentaram uma boa concord?ncia com os das medi??es efetuadas. Os resultados deste trabalho, tamb?m, concordaram com os resultados de outros autores, dispon?veis na literatura

Made available in DSpace on 2014-12-17T15:05:06Z (GMT). No. of bitstreams: 1 FranciscoCO.pdf: 1310311 bytes, checksum: f0b9fd0c2c5ee62f1c8154cb767565b0 (MD5) Previous issue date: 2007-06-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study describes about graduation s students difficulties of to draw functions graph. Specifically, we intend to observe their abilities evolution, as well as their difficulties during Calculus I subject in engineering course. For that, we show them publications about the elaboration of graphs and its difficulties in obstacle terms and some researches witch contain this subject and that it was done during postgraduate studies in mathematical education. It shows by research methodology aspects related to French didatic s mathematic and some theories of cognitive psychology considering the high value between theoretical-methodological relation that was evidenced in both theoretical conceptions about ways to understand and teach mathematic. This methodology is based on didactic engineering purpose, that consist in preliminaries analysis, conception and didactic sequence analysis prior, trials by application followed analysis up and conclusion. We had also used pedagogicals actions and analysis of results achieved, to classify types of errors made by the 2005 s students during second semester, from conceptions related to the episthemologic and didactics obstacles / Neste estudo descrevemos as dificuldades de um grupo de alunos de gradua??o no que diz respeito ao ato de tra?ar gr?ficos de fun??es. Especificamente, investigamos a evolu??o das suas habilidades, assim como suas dificuldades no decorrer da disciplina C?lculo I, no curso de Engenharia. Para tanto, analisamos publica??es sobre elabora??o de gr?ficos e suas dificuldades em termos de obst?culo, bem como abordamos alguns relat?rios de pesquisa relacionados ao tema em quest?o e que foram realizadas no ?mbito dos estudos da p?s-gradua??o em Educa??o Matem?tica. Mostramos que atrav?s dos aspectos relacionados ? linha francesa da Did?tica da Matem?tica e de algumas teorias da Psicologia Cognitiva, ? poss?vel estabelecer uma importante conex?o te?rico-metodol?gica entre ambas as concep??es te?ricas acerca dos modos de compreender e ensinar matem?tica. Esta metodologia fundamenta-se na proposta da Engenharia Did?tica, que consiste em an?lises preliminares, concep??o e an?lise a priori da seq??ncia did?tica, experimenta??o atrav?s de sua aplica??o seguida da an?lise a posteriori e conclus?o. Houve, tamb?m, a necessidade de recorremos a Interven??o Pedag?gica e An?lise dos Resultados Obtidos, para classificarmos e analisarmos os v?rios tipos de erros apresentados pelos alunos durante o segundo semestre de 2005, a partir das concep??es referentes aos obst?culos epistemol?gicos e did?ticos