Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-06-13T19:12:08Z No. of bitstreams: 1 FranciscoDasChagasDaSilvaJunior_TESE.pdf: 12071942 bytes, checksum: d85f48da1e07b1c67fd7d5ed15a593f5 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-06-14T21:11:29Z (GMT) No. of bitstreams: 1 FranciscoDasChagasDaSilvaJunior_TESE.pdf: 12071942 bytes, checksum: d85f48da1e07b1c67fd7d5ed15a593f5 (MD5) / Made available in DSpace on 2017-06-14T21:11:29Z (GMT). No. of bitstreams: 1 FranciscoDasChagasDaSilvaJunior_TESE.pdf: 12071942 bytes, checksum: d85f48da1e07b1c67fd7d5ed15a593f5 (MD5) Previous issue date: 2017-02-03 / Este trabalho aborda o problema de projeto de controladores adaptativos por posicionamento de polos para plantas incertas, monovari?veis, lineares e invariantes no tempo (LTI), tanto de fase m?nima como de fase n?o m?nima. No primeiro esquema apresentado, denominado Controle Adaptativo por Posicionamento de Polos e Estrutura Vari?vel (VS-APPC), os par?metros do controlador s?o calculados a cada instante de tempo a partir das estimativas dos par?metros da planta, que s?o geradas por leis chaveadas baseadas na teoria dos Sistemas com Estrutura Vari?vel (VSS), e de um polin?mio caracter?stico, escolhido com base em especifica??es de desempenho e que define a posi??o desejada para os polos de malha fechada. O segundo esquema, denominado Controle Adaptativo Intervalar por Posicionamento de Polos e Estrutura Vari?vel (IVS-APPC), ? projetado para plantas intervalares, ou seja, plantas cujos par?metros s?o desconhecidos mas limitados a intervalos conhecidos, que s?o comuns em situa??es pr?ticas onde muitas vezes os modelos de sistemas LTI tratados s?o na verdade aproxima??es de sistemas n?o-lineares, por exemplo, o que pode resultar em incertezas param?tricas significativas para os sistemas de controle. No projeto do IVS-APPC, os par?metros do controlador s?o calculados da mesma forma que no caso do VS-APPC, mas devem estar contidos em intervalos previamente calculados por um algoritmo de otimiza??o que busca solucionar um problema de Programa??o N?o-Linear, de forma a garantir que os polos de malha fechada permane?am em uma regi?o convexa definida pelas ra?zes de um polin?mio caracter?stico intervalar, cuja estabilidade ? garantida pelo Teorema de Kharitonov. A principal motiva??o deste trabalho ? a aplica??o dos esquemas propostos a plantas de fase n?o m?nima, j? que a abordagem de controle conhecida como Controle Adaptativo por Modelo de Refer?ncia e Estrutura Vari?vel (VS-MRAC), que tem apresentado ao longos dos ?ltimos anos resultados satisfat?rios de desempenho e robustez, ? restrita a plantas de fase m?nima. Resultados de simula??o s?o apresentados para ilustrar as propriedades dos esquemas propostos, como por exemplo transit?rio r?pido, sinal de controle suave sem filtragem e robustez a varia??es param?tricas.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-08T13:33:20Z No. of bitstreams: 1 2015 - Samara Macedo Pinto.pdf: 970121 bytes, checksum: f69dfd12be8357633a632969c91a1d3a (MD5) / Made available in DSpace on 2017-06-08T13:33:20Z (GMT). No. of bitstreams: 1 2015 - Samara Macedo Pinto.pdf: 970121 bytes, checksum: f69dfd12be8357633a632969c91a1d3a (MD5) Previous issue date: 2015-05-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Fish communities in developing countries have, in many cases, showed a decrease in the species richness and abundance over time as a result of anthropogenic impacts. We analyzed fish communities of three zones (inner, middle and outer) of the Sepetiba Bay (Southeastern Brazil) using identical sampling methods (bottom trawl) during four different time periods: 1987?1988; 1993?1995; 1998?2001 and 2012?2013. A total of 33,140 fish representing 127 species in 88 genera and 41 families were recorded. Our results revealed highly significant and consistent differences in the fish community structure among the bay zones, and a decreased in the fish richness and abundance over the time period. Changes in fish richness and abundance were related mostly to a sharp decrease that occurred in the inner bay zone, the most impacted bay area, and, to a lesser extent, in the middle zone between the two first (1987?1988 and 1993?1995) and the two latter time periods (1998?2001 and 2012?2013), whereas the outer zone remained comparatively stable over time. Spatial changes in the fish community structure among the bay zones were related to differences in salinity, transparency and depth with this latter variable, together with other factors, acting as a buffer for stabalizing community changes; however, these environmental variables explained little of the variation in the temporal changes. The most important changes over time in abundant species were the numerical decreases of the Ariid Cathorops spixii, the serranid Diplectrum radiale and sciaenid Cynoscion leiarchus, and increases of the sciaenid Micropogonias furnieri and the marine catfish Genidens genidens, with this latter species restricted to the inner and middle zones. This study adds long-term information on gradual fish community changes along spatial gradients of environmental and anthropogenic influences in embayment systems. It is perhaps timely to link conservation and management planning with historical information to protect fish biodiversity in tropical developing countries / As comunidades de peixes em pa?ses em desenvolvimento, em muitos casos, mostram uma diminui??o na riqueza e abund?ncia das esp?cies ao longo do tempo como resultado das evid?ncias dos impactos antropog?nicos. N?s analisamos as comunidades de peixes ao longo de tr?s zonas (interna, central e externa) da Ba?a de Sepetiba (Sudeste do Brasil), utilizando m?todos id?nticos de amostragem (bottom trawl) de peixes durante quatro per?odos temporais diferentes: 1987?1988; 1993?1995; 1998?2001 e 2012?2013. Registrou-se um total de 33.140 peixes representando 127 esp?cies em 88 g?neros e 41 fam?lias. Nossos resultados revelaram diferen?as altamente significativas e consistentes na estrutura da comunidade de peixes entre as zonas da ba?a e uma diminui??o na riqueza de esp?cies e abund?ncia ao longo do per?odo de estudo. As mudan?as na riqueza de esp?cies e abund?ncia foram relacionadas, principalmente, ? uma forte queda que ocorreu na zona interna da ba?a, ?rea esta mais afetada e, em menor medida, na zona central entre os dois primeiros (1987?1988 e 1993?1995) e os ?ltimos dois per?odos temporais (1998?2001 e 2012?2013), enquanto a zona exterior permaneceu relativamente est?vel ao longo do tempo. Mudan?as espaciais na estrutura da comunidade de peixes entre as zonas da ba?a foram relacionadas ?s diferen?as de salinidade, transpar?ncia e profundidade com este ?ltima vari?vel, em conjunto com outros fatores, atuando como um ?buffer? estabilizando mudan?as na comunidade; no entanto, essas vari?veis ambientais explicaram pouco a varia??o nas mudan?as temporais. As mudan?as mais importantes ao longo do tempo em esp?cies abundantes foi a diminui??o num?rica do Ariideo Cathorops spixii, do Serran?deo Diplectrum radiale e do Sciaen?deo Cynoscion leiarchus, e o aumento do Sciaen?deo Micropogonias furnieri e o bagre marinho Genidens genidens, com esta ?ltima esp?cie restrita ?s zonas interna e central. Este estudo acrescenta informa??o de longo prazo sobre mudan?as graduais nas comunidades de peixes ao longo de gradientes espaciais com influ?ncias ambientais e antr?picas no sistema de ba?a. Talvez seja oportuno vincular conserva??o e planejamento de gest?o com informa??es hist?ricas para proteger a biodiversidade de peixes em pa?ses tropicais em desenvolvimento.

Diazotrophic microbes reside in soybean nodules; however, other non-nitrogen fixing bacteria are a part of the interior nodule microbiome. Results from a previous greenhouse study show that a novel species of Pseudomonas associates with soybean nodules as a plant-growth promoting rhizobacteria (PGPR). This study observes the soybean growth promoting potential of Pseudomonas spp. in a field setting. Additionally, this study observed differences in soybean growth promotion based on amending the plant with isolated strains or a mixed culture of the species' strains. Two cultivars of soybean (Asgrow AG46X6 and Pioneer P48A60X) were either amended with isolated strains of the novel Pseudomonas spp. (referred to as PAMW1 and BUMW2 in this study), a mix of the two strains, or an uninoculated control. The study recorded measurements to observe growth, yield, and nitrogen fixation differences. The study uses two-way factorial ANOVAs and non-parametric, multivariate analyses to determine differences in growth promotion among samples. Soybean amended with PAMW1 has greater shoot mass, biomass, and height than other treatments. Through nonmetric multidimensional scaling (NMS), samples amended with a mixed culture or PAMW1 may be different regarding growth promotion relative to the non-amended samples. Univariate results support the hypothesis that the novel Pseudomonas spp. benefit soybean in a field setting. However, it is inconclusive whether a mixed culture amendment of multiple strains alters the overall growth promotion of soybean compared to samples amended with isolated strains. / Master of Science / Soil hosts a relatively abundant and diverse community of microorganisms. Moreover, the area of soil that interacts closely with plant roots and their associated exudates, called the rhizosphere, has a significantly greater microbial abundance than surrounding bulk soil. Interactions between microbes and the plant often promote plant growth because of secondary metabolites produced by these beneficial microbes. One particular bacterial species, belonging to the Pseudomonas genus, was discovered and extracted from the soybean nodule interior. Nitrogen-fixing bacteria predominantly reside in the soybean nodule, yet this microorganism cannot fix nitrogen. Although trace amounts of non-nitrogen-fixing bacteria reside in the soybean nodule, this novel species has a relatively high abundance. This study determines the benefits of this species in the soybean nodule. Following positive results in a greenhouse study, this field experiment observes variance in soybean growth and productivity based on their received bacterial amendment. For this study, two soybean cultivars were either amended with an isolated strain of this species, a mix of the two strains, or left uninoculated to serve as a control. Numerous recorded measurements serve as indices of soybean growth and productivity. The results suggest that this novel Pseudomonas species benefits the plant by significantly improving biomass. With further research, this species can potentially serve as an environmentally sensitive and sustainable alternative to fertilizers through its ability to promote soybean growth.

Incluir como ag?ncias financiadoras: Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG), Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES), Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq). / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-01-05T18:15:19Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thaiza_silva_campideli.pdf: 3972827 bytes, checksum: d46dcbd4e39c922c90034d3992c8ad54 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-01-19T16:55:01Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thaiza_silva_campideli.pdf: 3972827 bytes, checksum: d46dcbd4e39c922c90034d3992c8ad54 (MD5) / Made available in DSpace on 2018-01-19T16:55:01Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thaiza_silva_campideli.pdf: 3972827 bytes, checksum: d46dcbd4e39c922c90034d3992c8ad54 (MD5) Previous issue date: 2017 / Esta pesquisa foi realizada com o objetivo de avaliar a sensibilidade dos valores gen?ticos aos n?veis diet?ticos de lisina digest?vel para caracter?sticas de desempenho e medidas morfom?tricas de til?pias do Nilo da linhagem tailandesa. Vinte e nove fam?lias de irm?os completos foram produzidas pelo acasalamento de 21 machos e 29 f?meas. A distribui??o entre os tanques foi feita aleatoriamente, por fam?lia, ap?s marca??o dos peixes, entre 94 a 109 dias de idade, at? formar um lote inicial de vinte alevinos por tanque, totalizando 700 peixes. ? idade aproximada de 150 dias os peixes foram aleatoriamente redistribu?dos no sistema, at? formar lotes com aproximadamente 138 peixes por n?vel de lisina digest?vel na dieta. Os peixes foram alimentados quatro vezes ao dia com dietas contendo diferentes n?veis de lisina digest?vel: 1,43; 1,53; 1,63; 1,73; e 1,83% nas idades entre 94 a 150 dias; e 1,28; 1,38; 1,48; 1,58 e 1,68% a partir da idade de 150 at? 255 dias. As informa??es individuais das til?pias (peso, comprimento total, comprimento padr?o, comprimento de cabe?a, altura e largura) foram padronizadas para 150, 185, 220 e 255 dias de idade. A partir de ent?o foram calculados o ganho de peso total, o ganho de peso di?rio, rela??o entre cabe?a e comprimento padr?o, rela??o entre largura e altura e a rela??o entre comprimento padr?o e comprimento total. Para as an?lises foi utilizado modelo de regress?o aleat?ria, sob modelo animal uni-caracter?stica. Foram testados modelos de ordens 2 e 3 do polin?mio de Legendre para o efeito fixo e ordem 2 para os efeitos gen?tico aditivo e de fam?lia e testados modelos com vari?ncia residual homog?nea (1classe) a heterog?nea (2, 3, e 4 classes). Os modelos que proporcionaram melhor ajuste na maioria das caracter?sticas foram os que consideraram vari?ncia residual homog?nea. De forma geral, os valores da correla??o de posto foram altas. As normas de rea??o de 25 til?pias tailandesas amostradas aleatoriamente indicaram altera??o na sensibilidade dos valores gen?ticos de algumas caracter?sticas ?s mudan?as no n?vel nutricional de lisina digest?vel. Observou-se, portanto, que as til?pias apresentam altera??o nos valores gen?ticos, sugerindo de maneira geral, a exist?ncia da intera??o gen?tipo x n?veis de lisina digest?vel para caracter?sticas, o que pode acarretar em sele??o de diferentes animais nos diferentes ambientes. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / This research was carried out with the aim of evaluating the sensitivity of breeding values to dietary digestible lysine level for performance traits and morphometric measurements of Nile tilapia of Thai lineage. Twenty-nine full sib families were produced by mating 21 males and 29 females. The distribution among the tanks was randomized by family, after marking the fish, between 94 and 109 days of age, until forming an initial batch of twenty fingerlings per tank, totaling 700 fish. At the approximate age of 150 days the fish were randomly redistributed into the system until they formed lots with approximately 138 fish per level of digestible lysine in the diet. Four times a day the fishes were fed diets containing different levels of lysine: 1.43; 1.53; 1.63; 1.73 and 1.83% in the growing phase; and 1.28; 1.38; 1.48; 1.58 and 1.68% in the finishing phase. The individual tilapia information (weight, total length, standard length, head length, height and width) were standardized for 150, 185, 220 and 255 days of age. From then on the weight gain, daily weight gain, head to standard length ratio, width to height ratio and the relationship between standard length and total length were calculated. . For the analyses, a random regression model was used under a single animal model. Legendre polynomial models of 2 and 3 orders were tested for the fixed effect, and of order 2 for the additive and family genetic effects. In addition, models were also tested using homogeneous residual variance (1 class) and heterogeneous variance (2, 3, and 4 classes). The models that provide better fit in most of the characteristics were those that considered homogeneous residual variance. In general, the rank correlations of breeding values of pairs of dietary digestible lysine levels were high. The reaction norms of 25 randomly sampled Thai tilapia showed change in the sensitivity of breeding values of some traits to changes in dietary digestible lysine level. Therefore, it was observed that breeding values of tilapia traits generally changed along the environment gradient, suggesting the existence of genotype x dietary digestible lysine level interaction which can lead to the selection of different fishes in different environments.

Made available in DSpace on 2014-12-17T14:03:44Z (GMT). No. of bitstreams: 1 MarciaDAD_DISSERT.pdf: 4264187 bytes, checksum: 68a1d188a3ddcbd9b3e88211ae1a47e7 (MD5) Previous issue date: 2014-08-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Shrimp farming is one of the activities that contribute most to the growth of global aquaculture. However, this business has undergone significant economic losses due to the onset of viral diseases such as Infectious Myonecrosis (IMN). The IMN is already widespread throughout Northeastern Brazil and affects other countries such as Indonesia, Thailand and China. The main symptom of disease is myonecrosis, which consists of necrosis of striated muscles of the abdomen and cephalothorax of shrimp. The IMN is caused by infectious myonecrosis virus (IMNV), a non-enveloped virus which has protrusions along its capsid. The viral genome consists of a single molecule of double-stranded RNA and has two Open Reading Frames (ORFs). The ORF1 encodes the major capsid protein (MCP) and a potential RNA binding protein (RBP). ORF2 encodes a probable RNA-dependent RNA polymerase (RdRp) and classifies IMNV in Totiviridae family. Thus, the objective of this research was study the IMNV complete genome and encoded proteins in order to develop a system differentiate virus isolates based on polymorphisms presence. The phylogenetic relationship among some totivirus was investigated and showed a new group to IMNV within Totiviridae family. Two new genomes were sequenced, analyzed and compared to two other genomes already deposited in GenBank. The new genomes were more similar to each other than those already described. Conserved and variable regions of the genome were identified through similarity graphs and alignments using the four IMNV sequences. This analyze allowed mapping of polymorphic sites and revealed that the most variable region of the genome is in the first half of ORF1, which coincides with the regions that possibly encode the viral protrusion, while the most stable regions of the genome were found in conserved domains of proteins that interact with RNA. Moreover, secondary structures were predicted for all proteins using various softwares and protein structural models were calculated using threading and ab initio modeling approaches. From these analyses was possible to observe that the IMNV proteins have motifs and shapes similar to proteins of other totiviruses and new possible protein functions have been proposed. The genome and proteins study was essential for development of a PCR-based detection system able to discriminate the four IMNV isolates based on the presence of polymorphic sites / A carcinicultura ? uma das atividades que mais contribui para o crescimento da aquicultura mundial. Entretanto, esta atividade vem sofrendo perdas econ?micas significativas devido ao surgimento de doen?as virais como a Mionecrose Infecciosa (IMN). A IMN j? est? disseminada em toda regi?o Nordeste do Brasil e atingiu outros pa?ses como Indon?sia, Tail?ndia e China. O principal sintoma da doen?a ? a mionecrose, que consiste na necrose dos m?sculos estriados do abd?men e do cefalot?rax do camar?o. A IMN ? causada pelo v?rus da mionecrose infecciosa (IMNV), um v?rus n?o envelopado que apresenta protrus?es ao longo de seu caps?deo. O genoma viral ? formado por uma ?nica mol?cula de RNA dupla fita e possui duas Open Reading Frames (ORFs). A ORF1 codifica a prote?na principal do caps?deo (MCP) e uma poss?vel prote?na de liga??o a RNA (RBP). A ORF2 codifica uma prov?vel RNA polimerase dependente de RNA (RdRp) e classifica o IMNV dentro da fam?lia Totiviridae. Assim, o objetivo desse estudo foi estudar o genoma completo do IMNV e as prote?nas codificadas no intuito de desenvolver um sistema que identificasse diferentes isolados do v?rus com base na presen?a de polimorfismos. A rela??o filogen?tica entre alguns totiv?rus foi investigada e mostrou um novo grupo para o IMNV dentro da fam?lia Totiviridae. Dois novos genomas foram sequenciados, analisados e comparados a outros dois genomas j? depositados no GenBank. Os novos genomas foram mais semelhantes entre si do que com aqueles j? descritos. Regi?es vari?veis e conservadas do genoma foram identificadas atrav?s de gr?ficos de similaridade e alinhamentos utilizando as quatro sequ?ncias do IMNV. Esta an?lise possibilitou o mapeamento de s?tios polim?rficos e revelou que a regi?o mais vari?vel do genoma se encontra na primeira metade da ORF1 e coincide com as regi?es que possivelmente codificam a protrus?o viral, enquanto que as regi?es mais est?veis se encontraram em dom?nios conservados de prote?nas que interagem com o RNA. Al?m disso, estruturas secund?rias foram preditas para todas as prote?nas empregando diversos softwares e modelos estruturais proteicos foram calculados usando modelagens por threading e simula??es ab initio. A partir dessas an?lises foi poss?vel observar que as prote?nas do IMNV possuem motivos e formas similares ?s prote?nas de outros totiv?rus, e novas poss?veis fun??es proteicas foram propostas. O estudo do genoma e das prote?nas foi essencial para o desenvolvimento de um sistema de detec??o baseado em PCR capaz de discriminar os quatro isolados do IMNV com base na presen?a de s?tios polim?rficos

Made available in DSpace on 2014-12-17T14:55:43Z (GMT). No. of bitstreams: 1 EricoCB_DISSERT.pdf: 1960043 bytes, checksum: 7c0ebefa8d09683721a890c3c7d00bbb (MD5) Previous issue date: 2010-03-26 / The Methods for compensation of harmonic currents and voltages have been widely used since these methods allow to reduce to acceptable levels the harmonic distortion in the voltages or currents in a power system, and also compensate reactive. The reduction of harmonics and reactive contributes to the reduction of losses in transmission lines and electrical machinery, increasing the power factor, reduce the occurrence of overvoltage and overcurrent. The active power filter is the most efficient method for compensation of harmonic currents and voltages. The active power filter is necessary to use current and voltage controllers loop. Conventionally, the current and voltage control loop of active filter has been done by proportional controllers integrative. This work, investigated the use of a robust adaptive control technique on the shunt active power filter current and voltage control loop to increase robustness and improve the performance of active filter to compensate for harmonics. The proposed control scheme is based on a combination of techniques for adaptive control pole placement and variable structure. The advantages of the proposed method over conventional ones are: lower total harmonic distortion, more flexibility, adaptability and robustness to the system. Moreover, the proposed control scheme improves the performance and improves the transient of active filter. The validation of the proposed technique was verified initially by a simulation program implemented in C++ language and then experimental results were obtained using a prototype three-phase active filter of 1 kVA / Os m?todos para compensa??o de correntes e tens?es harm?nicas v?m sendo bastante utilizados, visto que esses m?todos permitem reduzir a n?veis aceit?veis as distor??es harm?nicas nas tens?es ou correntes em um sistema el?trico de pot?ncia, e ainda, compensar reativos. A redu??o de harm?nicas e reativos contribuem para: a diminui??o das perdas nas linhas de transmiss?o e nas m?quinas el?tricas, o aumento do fator de pot?ncia e a redu??o de ocorr?ncias de sobretens?es e sobrecorrentes. O filtro ativo de pot?ncia ? o m?todo mais eficiente para compensa??o de correntes e tens?es harm?nicas. No filtro ativo de pot?ncia ? necess?ria a utiliza??o de controladores para as malhas de corrente e tens?o. Convencionalmente, o controle dessas malhas tem sido feito por controladores proporcionais integrativos. Neste trabalho, ? investigado o uso de uma t?cnica de controle adaptativo robusto nas malha de corrente e tens?o, do filtro ativo de pot?ncia em paralelo trif?sico, para aumentar a robustez e melhorar o desempenho desse filtro ativo na compensa??o de harm?nicos. A t?cnica de controle proposta ? baseada na combina??o das t?cnicas de controle adaptativo por posicionamento de p?los e de estrutura vari?vel. As vantagens do m?todo proposto sobre os convencionais s?o: menor taxa de distor??o harm?nica, maior flexibilidade, capacidade de adapta??o e robustez para o sistema. Al?m disso, a t?cnica de controle proposta aumenta o desempenho e melhora o transit?rio do filtro ativo. A valida??o da t?cnica proposta foi verificada inicialmente atrav?s de um programa de simula??o implementado em linguagem C ++ e em seguida foram obtidos resultados experimentais usando um prot?tipo de um filtro ativo trif?sico de 1 kVA

Made available in DSpace on 2014-12-17T14:56:02Z (GMT). No. of bitstreams: 1 FranciscoCSJ.pdf: 396492 bytes, checksum: c7b91bb21a15450749eb2738a17c2f3e (MD5) Previous issue date: 2005-07-28 / There are two main approaches for using in adaptive controllers. One is the so-called model reference adaptive control (MRAC), and the other is the so-called adaptive pole placement control (APPC). In MRAC, a reference model is chosen to generate the desired trajectory that the plant output has to follow, and it can require cancellation of the plant zeros. Due to its flexibility in choosing the controller design methodology (state feedback, compensator design, linear quadratic, etc.) and the adaptive law (least squares, gradient, etc.), the APPC is the most general type of adaptive control. Traditionally, it has been developed in an indirect approach and, as an advantage, it may be applied to non-minimum phase plants, because do not involve plant zero-pole cancellations. The integration to variable structure systems allows to aggregate fast transient and robustness to parametric uncertainties and disturbances, as well. In this work, a variable structure adaptive pole placement control (VS-APPC) is proposed. Therefore, new switching laws are proposed, instead of using the traditional integral adaptive laws. Additionally, simulation results for an unstable first order system and simulation and practical results for a three-phase induction motor are shown / Existem dois m?todos principais para a constru??o de controladores adaptativos. Um deles ? o controle adaptativo por modelo de refer?ncia (MRAC) e o outro ? o controle adaptativo por posicionamento de p?los (APPC). No MRAC, um modelo de refer?ncia ? escolhido para gerar a trajet?ria desejada que o sinal de sa?da da planta deve seguir, e ele pode requerer o cancelamento de zeros da planta. Devido a sua flexibilidade em escolher a metodologia de projeto do controlador (realimenta??o de estado, projeto de compensador, linear quadr?tico, etc.) e a lei adaptativa (m?nimos quadrados, m?todo do gradiente, etc.), o APPC ? o tipo mais geral de controle adaptativo. Tradicionalmente, vem sendo desenvolvido em uma abordagem indireta e, como uma vantagem, pode ser aplicado a plantas de fase n?o-m?nima, j? que n?o envolve cancelamentos de zeros e p?los. A integra??o aos sistemas com estrutura vari?vel permite agregar rapidez no transit?rio e robustez ?s varia??es param?tricas e perturba??es. O objetivo deste trabalho ? desenvolver um controlador adaptativo por posicionamento de p?los e estrutura vari?vel (VS-APPC). Portanto, s?o propostas leis chaveadas em substitui??o ?s leis adaptativas integrais tradicionais. Adicionalmente, s?o apresentadas simula??es para uma planta de primeira ordem inst?vel, assim como simula??es e resultados pr?ticos da aplica??o da t?cnica proposta a um motor de indu??o trif?sico

Made available in DSpace on 2014-12-17T14:56:15Z (GMT). No. of bitstreams: 1 DanielWH_DISSERT.pdf: 3818359 bytes, checksum: ac34198b688307ffda10243b5ad47c74 (MD5) Previous issue date: 2013-09-13 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In the last decade, the renewable energy sources have present a major propulsion in the world due to several factors: political, environmental, financial and others. Within this context, we have in particular the energy obtained through wind, wind energy - that has highlighted with rapid growth in recent years, including in Brazil, mostly in the Northeast, due to it s benefit-cost between the clean energies. In this context, we propose to compare the variable structure adaptive pole placement control (VS-APPC) with a traditional control technique proportional integral controller (PI), applied to set the control of machine side in a conversion system using a wind generator based on Double-Fed Induction Generator (DFIG). Robustness and performance tests were carried out to the uncertainties of the internal parameters of the machine and variations of speed reference. / As fontes de energia renov?veis t?m, na ?ltima d?cada, ganho uma grande propuls?o em todo o mundo devido aos mais diversos fatores: pol?ticos, ambientais, financeiros, entre outros. Dentro deste universo, temos, em especial, a energia obtida atrav?s do vento, energia e?lica - que tem se destacado com um crescimento vertiginoso nos ?ltimos anos, inclusive no Brasil, principalmente na regi?o Nordeste, devido ao seu custo-benef?cio entre as energias "limpas". Neste cen?rio, prop?e-se a compara??o do controlador por posicionamento de polos e estrutura vari?vel (VS-APPC) com o controlador proporcional integral (PI) aplicados em um sistema de convers?o de energia e?lica que utiliza um gerador de indu??o duplamente alimentado (Double-Fed Induction Generator- DFIG). Testes de robustez e desempenho foram realizados com incertezas nos par?metros da m?quina e varia??es de refer?ncia de velocidade

Made available in DSpace on 2014-12-17T15:14:51Z (GMT). No. of bitstreams: 1 JoaoMS.pdf: 634960 bytes, checksum: 579213d21eb24a6a8d342d2c3b15bc3d (MD5) Previous issue date: 2003-06-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work we investigate the stochastic behavior of a large class of systems with variable damping which are described by a time-dependent Lagrangian. Our stochastic approach is based on the Langevin treatment describing the motion of a classical Brownian particle of mass m. Two situations of physical interest are considered. In the first one, we discuss in detail an application of the standard Langevin treatment (white noise) for the variable damping system. In the second one, a more general viewpoint is adopted by assuming a given expression to the so-called collored noise. For both cases, the basic diffententiaql equations are analytically solved and al the quantities physically relevant are explicitly determined. The results depend on an arbitrary q parameter measuring how the behavior of the system departs from the standard brownian particle with constant viscosity. Several types of sthocastic behavior (superdiffusive and subdiffusive) are obteinded when the free pamameter varies continuosly. However, all the results of the conventional Langevin approach with constant damping are recovered in the limit q = 1 / Neste trabalho n?s investigamos o comportamento estoc?stico de uma grande classe de sistemas com amortecimento vari?vel descritos por uma lagraniana dependente do tempo. Nossa abordagem estoc?stica ? baseada no formalismo de Langevin descrevendo o comportamento de uma part?cula browniana cl?ssica de massa m. Duas situa??es de interesse f?sico s?o consideradas. Inicialmente, uma aplica??o do tratamento padr?o de Langevin (ru?do branco) para viscosidade vari?vel ? discutido em detalhe. Na segunda abordagem, um ponto de vista mais geral ? adotado supondo uma dada express?o para o chamado ru?do branco. Em ambos os casos as equa??es diferenciais b?sicas s?o analiticamente resolvidas, e todas as quantidades fisicamente relevantes s?o explicitamente determinadas. Os resultados dependem de um par?metro arbitr?rio (q) medindo como o comportamento din?mico do sistema se afasta daquele apresentado pela part?cula browniana com viscosidade constante. V?rios tipos de comportamentos estoc?sticos (subsifusivos and superdifusivos) s?o obtidos quando o par?metro livre q varia continuamente. Contudo, no limite q -> 1, todos os resultados da abordagem de Langevin convencional s?o recuperados

Made available in DSpace on 2014-12-17T15:26:39Z (GMT). No. of bitstreams: 1 MarianaBS_DISSERT.pdf: 5316617 bytes, checksum: 4fb0344851aa8f373aa2dab90bb6d3c5 (MD5) Previous issue date: 2012-05-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work, the paper of Campos and Dorea [3] was detailed. In that article a Kernel Estimator was applied to a sequence of random variables with general state space, which were independent and identicaly distributed. In chapter 2, the estimator?s properties such as asymptotic unbiasedness, consistency in quadratic mean, strong consistency and asymptotic normality were verified. In chapter 3, using R software, numerical experiments were developed in order to give a visual idea of the estimate process / Neste trabalho estudamos um dos m?todos n?o-param?trico: os Estimadores do Tipo N?cleo associado a uma sequ?ncia de vari?veis aleat?rias independentes e identicamente distribu?das com espa?o de estados geral, mais precisamente o trabalho de Campos e Dorea [3]. No Cap?tulo 2 verificamos as boas qualidades dessa classe de estimadores como n?o v?cio assint?tico, converg?ncia em m?dia quadr?tica, consist?ncia forte e normalidade assint?tica. No Cap?tulo 3 com o auxilio do software R temos uma id?ia visual do que ocorre no processo de estima??o