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Regulador eletromagn?tico de frequ?ncia aplicado no controle de velocidade de geradores e?licosSilva, Paulo Vitor 11 May 2015 (has links)
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Previous issue date: 2015-05-11 / A necessidade constante de novas fontes de energias renov?veis vem promovendo
cada vez mais o aumento de investimentos nessa ?rea. Dentre essas fontes, a energia
e?lica vem tomando grande destaque. Torna-se importante promover a busca pelo aprimoramento
das tecnologias envolvidas nas topologias de aerogeradores, buscando alternativas
que aumentem o rendimento obtido, apesar da irregularidade da velocidade do
vento.
Este trabalho apresenta um novo sistema para controle de velocidade, aqui aplicado
em aerogeradores, o Regulador Eletromagn?tico de Frequ?ncia (REF). Um dos dispositivos
mais utilizados em algumas topologias s?o as caixas de engrenagens mec?nicas
que, al?m de uma vida ?til curta, representam frequentemente, fontes de ru?do e defeitos.
O REF dispensa essas caixas de transmiss?o, representando um avan?o tecnol?gico, utilizando
para isso uma m?quina de indu??o adaptada, na qual o estator passa a ser m?vel,
solid?rio ao eixo da turbina.
Na topologia utilizada neste trabalho, o REF tamb?m permite dispensar o uso de conversores
eletr?nicos para estabelecer o acoplamento entre o gerador e a rede el?trica,
raz?o pela qual tamb?m proporciona a possibilidade de obten??o de gera??o em corrente
alternada, com tens?o e frequ?ncia constantes, onde n?o exista a rede el?trica.
Respons?vel pelo controle da velocidade mec?nica do gerador, o REF pode ser ?til
em outros sistemas de transmiss?o onde o controle de velocidade mec?nica de sa?da seja
o objetivo.
Al?m disso, por operar atrav?s da combina??o de duas entradas, uma mec?nica e outra
el?trica, o REF multiplica as possibilidades de aplica??es por ser apto ao acoplamento
sin?rgico entre energias de matrizes diferentes, e, por tais motivos, possibilita que as diversas
fontes de energia envolvidas sejam desacopladas da rede, sendo o gerador s?ncrono
o respons?vel pela conex?o do sistema com a rede el?trica, simplificando as estrat?gias
de controle quanto ? pot?ncia injetada na mesma.
Resultados de simula??o e experimentais s?o apresentados no decorrer do trabalho,
voltados a um aerogerador, validando a proposta em rela??o a efici?ncia no controle de
velocidade do sistema para diferentes condi??es de vento. / The constant necessity for new sources of renewable energy is increasingly promoting
the increase of investments in this area. Among other sources, the wind power has
been becoming prominent. It is important to promote the search for the improvement of
the technologies involved in the topologies of the wind turbines, seeking for alternatives
which enhance the gotten performance, despite the irregularity of the wind speed.
This study presents a new system for speed control, in this case applied to the wind
turbines - the Electromagnetic Frequency Regulator (EFR). One of the most used devices
in some topologies is the mechanical gearboxes which, along with a short service life,
often represent sources of noise and defects. The EFR does not need these transmission
boxes, representing a technological advancement, using for that an adapted induction
machine, in which the stator becomes mobile, supportive to the axis of the turbine.
In the topology used in this study, the EFR also allows us to leave out the usage of the
eletronic converters to establish the coupling between the generator and the electrical grid.
It also the reason why it provides the possibility of obtaining the generation in alternating
current, with constant voltage and frequency, where there is no electrical grid.
Responsable for the mechanical speed control of the generator, the EFR can be useful
in other transmission systems in which the mechanical speed control output is the
objective.
In addition, the EFR operates through the combination of two inputs, a mechanical
and other electrical. It multiplies the possibilities of application because it is able
to synergistic coupling between different arrays of energy, and, for such reasons, it enables
the various sources of energy involved to be uncoupled from the network, being
the synchronous generator responsible for the system connection with the electrical grid,
simplifying the control strategies on the power injected in it.
Experimental and simulation results are presented through this study, about a wind
turbine, validating the proposal related to the efficience in the speed control of the system
for different wind conditions.
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Controle em modo dual adaptativo robusto aplicado a um sistema de gera??o de energia el?tricaRomano, Renata Leiros 23 June 2015 (has links)
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Previous issue date: 2015-06-23 / Os geradores s?ncronos, predominantes nos sistemas de gera??o de energia el?trica,
devem fornecer valores de tens?o e frequ?ncia constantes para que seja obtida uma boa
qualidade da energia gerada. Por?m, para situa??es em que esses sistemas sofrem gran-
des varia??es de carga, h? dificuldade de que sejam mantidos os valores nominais nas
sa?das do gerador devido ?s incertezas param?tricas, n?o linearidades e alto grau de aco-
plamento entre as vari?veis. Prop?e-se, ent?o, a aplica??o do Controlador em Modo Dual
Adaptativo Robusto (DMARC) para o controle do fluxo de campo, em substitui??o aos
tradicionais controladores PIs. O DMARC estabelece uma liga??o entre um controlador
adaptativo por modelo de refer?ncia (MRAC) e um controlador adaptativo por modelo de
refer?ncia e estrutura vari?vel (VS-MRAC), incorporando as vantagens de desempenho
transit?rio do controlador VS-MRAC com as propriedades de regime permanente do con-
trolador MRAC convencional. S?o feitas an?lises atrav?s de simula??es como forma de
verificar o funcionamento do controlador proposto, bem como compar?-lo com o sistema
atualmente em uso. / Synchronous machines, widely used in energy generation systems, require constant
voltage and frequency to obtain good quality of energy. However, for large load variati-
ons, it is difficult to maintain outputs on nominal values due to parametric uncertainties,
nonlinearities and coupling among variables. Then, we propose to apply the Dual Mode
Adaptive Robust Controller (DMARC) in the field flux control loop, replacing the tradi-
tional PI controller. The DMARC links a Model Reference Adaptive Controller (MRAC)
and a Variable Structure Model Reference Adaptive Controller (VS-MRAC), incorpora-
ting transient performance advantages from VS-MRAC and steady state properties from
MRAC. Moreover, simulation results are included to corroborate the theoretical studies.
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Prote??o em sistemas el?tricos com gera??o distribu?da utilizando a transformada waveletPaiva, S?mara de Cavalcante 22 June 2015 (has links)
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Previous issue date: 2015-06-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Um sistema el?trico de pot?ncia t?pico ? caracterizado pela
centraliza??o da gera-
??o de energia. Entretanto, com a reestrutura??o do sistema
el?trico, esta topologia vem
modificando-se com a utiliza??o de geradores ao longo do sist
ema de distribui??o (gera-
??o distribu?da) que proporciona diversos benef?cios por l
ocalizar-se pr?ximo aos centros
de consumo. Com isso, a inser??o de geradores distribu?dos,
especialmente provenientes
de fontes renov?veis, no sistema brasileiro tende a se torna
r a cada ano mais comum. En-
tretanto, esta nova configura??o do sistema traz novos desafi
os concernentes ao controle,
opera??o e prote??o. Um dos principais problemas da gera??o
distribu?da nos sistemas de
prote??o ? a forma??o de ilhamentos, que pode resultar em ris
cos de seguran?a ?s pessoas
e a rede de energia el?trica. Dentre as diversas t?cnicas de p
rote??o de ilhamentos, as
t?cnicas passivas destacam-se devido ao custo de implement
a??o e simplicidade, sendo
necess?rias apenas medi??es de tens?o e corrente para detec
??o de problemas no sistema.
Prop?e-se neste trabalho um sistema de prote??o baseado na t
ransformada
wavelet
com
as fun??es de sobrecorrente, sub/sobretens?es e informa??
es dos transit?rios de falta para
r?pida detec??o e identifica??o de situa??es de falta no sist
ema. O esquema de prote??o
proposto foi avaliado por meio de estudos de simula??o e expe
rimental, apresentando de-
sempenho similar aos m?todos de sobrecorrente e sub/sobret
ens?o convencionais, por?m,
com o adicional da detec??o do instante exato das faltas. / A typical electrical power system is characterized by centr
alization of power gene-
ration. However, with the restructuring of the electric sys
tem, this topology is changing
with the insertion of generators in parallel with the distri
bution system (distributed gene-
ration) that provides several benefits to be located near to e
nergy consumers. Therefore,
the integration of distributed generators, especially fro
m renewable sources in the Brazi-
lian system has been common every year. However, this new sys
tem topology may result
in new challenges in the field of the power system control, ope
ration, and protection.
One of the main problems related to the distributed generati
on is the islanding formation,
witch can result in safety risk to the people and to the power g
rid. Among the several
islanding protection techniques, passive techniques have
low implementation cost and
simplicity, requiring only voltage and current measuremen
ts to detect system problems.
This paper proposes a protection system based on the wavelet
transform with overcur-
rent and under/overvoltage functions as well as infomation
of fault-induced transients in
order to provide a fast detection and identification of fault
s in the system. The propo-
sed protection scheme was evaluated through simulation and
experimental studies, with
performance similar to the overcurrent and under/overvolt
age conventional methods, but
with the additional detection of the exact moment of the fault.
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Estudo da varia??o da periodicidade e do acoplamento entre superf?cies seletivas de frequ?ncia com elementos fractais e helicoidais em estruturas de multicamadasTrindade, Jos? Idifranse Aguiar 30 January 2015 (has links)
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Previous issue date: 2015-01-30 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Este trabalho tem como objetivo investigar o comportamento de elementos fractais e elementos helicoidais em estruturas planares de microfita. Em particular, as superf?cies seletivas de frequ?ncia (FSS) tiveram seus elementos convencionais alterados para formatos fractais e para o formato helicoidal. O substrato diel?trico usado ? de fibra de vidro (FR-4) e tem espessura de 1,5 mm, permissividade el?trica relativa de 4,4 e tangente de perdas igual a 0,02. Para as FSS, adotou-se a geometria fractal pentagonal de D?rer e a geometria helicoidal. Para efetuar as medi??es, foram utilizadas duas antenas cornetas em visada direta, conectadas por cabo coaxial a um analisador de redes vetorial. Alguns prot?tipos foram selecionados para fabrica??o e medi??o. A partir dos resultados preliminares obtidos, objetivou-se encontrar aplica??es pr?ticas para as estruturas a partir do cascateamento entre elas. Para as FSSs com elementos fractais de D?rer, observou-se um comportamento multibanda proporcionado pela geometria fractal, ao mesmo tempo em que a largura de banda se tornou estreita na medida em que o n?vel de itera??o fractal aumentou, tornando-a uma estrutura mais seletiva em frequ?ncia, com um maior fator de qualidade. Uma an?lise param?trica possibilitou a an?lise da influ?ncia da varia??o da camada de ar entre elas. As estruturas fractais pentagonais foram consideradas e cascateadas. O cascateamento entre determinadas estruturas pentagonais apresentou um comportamento tri-band para determinados valores da camada de ar entre elas, com aplica??es na banda licenciada 2,5 GHz (2,3 ~ 2,7 GHz), e 3,5 GHz (3,3 ~ 3,8 GHz). Para as FSSs com elementos helicoidais, seis estruturas foram consideradas. A partir de resultados preliminares obtidos com a an?lise isolada das estruturas, o cascateamento entre elas proporcionou o aumento da largura de banda, na medida em que a espessura da camada de ar aumenta. Com a finalidade de encontrar aplica??es pr?ticas para as estruturas helicoidais cascateadas, as estruturas propostas foram cascateadas e as mesmas encontraram aplica??es na banda-X (8,0 ~ 12,0 GHz), e na banda n?o licenciada que compreende a faixa de 5,25 a 5,85 GHz. Na caracteriza??o num?rica e experimental das estruturas abordadas, utilizou-se, respectivamente, o software comercial Ansoft Designere um analisador de redes vetorial, modelo N5230A da Agilent. / This work aims to investigate the behavior of fractal and helical elements structures in planar microstrip. In particular, the frequency selective surfaces (FSSs) had changed its conventional elements to fractal and helical formats. The dielectric substrate used was fiberglass (FR-4) and has a thickness of 1.5 mm, a relative permittivity 4.4 and tangent loss equal to 0.02. For FSSs, was adopting the D?rer?s fractal geometry and helical geometry. To make the measurements, we used two antennas horns in direct line of sight, connected by coaxial cable to the vector network analyzer. Some prototypes were select for built and measured. From preliminary results, it was aimed to find practical applications for structures from the cascading between them. For FSSs with D?rer?s fractal elements was observed behavior provided by the multiband fractal geometry, while the bandwidth has become narrow as the level of iteration fractal increased, making it a more selective frequency with a higher quality factor. A parametric analysis allowed the analysis of the variation of the air layer between them. The cascading between fractal elements structure were considered, presented a tri-band behavior for certain values of the layer of air between them, and find applications in the licensed 2.5GHz band (2.3-2.7) and 3.5GHz band (3.3-3.8). For FSSs with helical elements, six structures were considered, namely H0, H1, H2, H3, H4 and H5. The electromagnetic behavior of them was analyzed separately and cascaded. From preliminary results obtained from the separate analysis of structures, including the cascade, the higher the bandwidth, in that the thickness of the air layer increases. In order to find practical applications for helical structures cascaded, the helical elements structure has been cascaded find applications in the X-band (8.0-12.0) and unlicensed band (5.25-5.85). For numerical and experimental characterization of the structures discussed was used, respectively, the commercial software Ansoft Designer and a vector network analyzer, Agilent N5230A model.
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Metodologia de estima??o de estados para tratamento de medi??es err?neas e registros n?o sincronizados em algoritmos de localiza??o de faltas em linhas de transmiss?oCruz, Melinda Cesianara Silva da 17 July 2015 (has links)
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Previous issue date: 2015-07-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O desempenho de algoritmos para localiza??o de faltas em linhas de transmiss?o est? diretamente relacionado ? exatid?o dos seus dados de entrada. Assim, fatores como erros nos par?metros da linha de transmiss?o, falhas na sincroniza??o de registros oscilogr?ficos e erros em medi??es de tens?o e de corrente podem influenciar de forma significativa as ferramentas que usam dados err?neos para indicar o local de defeitos. Este trabalho apresenta uma nova metodologia para localiza??o de faltas em linhas de transmiss?o, baseada na teoria de estima??o de estados, de forma a determinar o local mais prov?vel de ocorr?ncia de curtos-circuitos atrav?s da considera??o de erros sistem?ticos real?sticos que podem estar presentes nas medi??es de tens?o e de corrente. O algoritmo foi implementado em duas etapas: pr?-falta e p?s-falta. Na primeira etapa, admitindo dados n?o sincronizados, estima-se o ?ngulo de sincroniza??o e os par?metros de sequ?ncia positiva da linha de transmiss?o, e na segunda, estima-se a dist?ncia de falta. Al?m de calcular o valor mais prov?vel para a dist?ncia de falta, a partir da considera??o de erros nas medi??es, a vari?ncia associada a esta dist?ncia tamb?m ? determinada, usando defini??es da teoria de erros. Essa ? uma das principais contribui??es deste trabalho, visto que, a partir o algoritmo proposto, ? poss?vel determinar uma regi?o de prov?vel incid?ncia da falta, com aproximadamente 95,45% de confian?a. Testes para avalia??o e valida??o da metodologia foram realizados a partir de registros reais de falta e a partir de simula??es de sistemas fict?cios de transmiss?o no software ATP. Os resultados obtidos s?o relevantes para mostrar que o estimador de localiza??o de faltas desenvolvido apresenta bom desempenho mesmo adotando vari?ncias real?sticas. / The performance of algorithms for fault location i
n transmission lines is directly
related to the accuracy of its input data. Thus, fa
ctors such as errors in the line parameters,
failures in synchronization of oscillographic recor
ds and errors in measurements of voltage
and current can significantly influence the accurac
y of algorithms that use bad data to indicate
the fault location. This work presents a new method
ology for fault location in transmission
lines based on the theory of state estimation in or
der to determine the location of faults more
accurately by considering realistic systematic erro
rs that may be present in measurements of
voltage and current. The methodology was implemente
d in two stages: pre-fault and post-
fault. In the first step, assuming non-synchronized
data, the synchronization angle and
positive sequence line parameters are estimated, an
d in the second, the fault distance is
estimated. Besides calculating the most likely faul
t distance obtained from measurement
errors, the variance associated with the distance f
ound is also determined, using the errors
theory. This is one of the main contributions of th
is work, since, with the proposed algorithm,
it is possible to determine a most likely zone of f
ault incidence, with approximately 95,45%
of confidence. Tests for evaluation and validation
of the proposed algorithm were realized
from actual records of faults and from simulations
of fictitious transmission systems using
ATP software. The obtained results are relevant to
show that the proposed estimation
approach works even adopting realistic variances, c
ompatible with real equipments errors.
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Topologia de gerador de dist?rbios el?tricos baseada em conversores de pot?nciaChaves J?nior, Emanoel Raimundo Queiroz 19 June 2015 (has links)
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Previous issue date: 2015-06-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Dist?rbios el?tricos como afundamentos de tens?o, interrup??es e desequil?brios de
tens?o podem causar s?rios problemas para os consumidores e para as empresas de gera??o
e transmiss?o de energia. Nos ?ltimos anos, essas empresas de servi?os el?tricos
v?m empregando t?cnicas e equipamentos de prote??o para evitar a ocorr?ncia dist?rbios
ou para amenizar os seus efeitos no sistema. Geradores de dist?rbios s?o utilizados
para analisar o comportamento de equipamentos el?tricos e eletr?nicos frente a poss?veis
dist?rbios el?tricos. A an?lise dessas falhas permite o desenvolvimento equipamentos
de prote??o adequados. Neste trabalho ? apresentado o desenvolvimento de um gerador
de dist?rbios baseado em conversores de pot?ncia que, aliado com uma estrat?gia de
controle, ? capaz de gerar v?rios tipos de dist?rbios sim?tricos como: afundamentos trif?-
sicos, eleva??es trif?sicas e inje??o de harm?nicos. A estrat?gia de controle ? baseada no
controle linear discreto e no controle repetitivo. S?o detalhadas as etapas do projeto dos
controladores e do filtro utilizado para a redu??o de harm?nicos na sa?da. S?o apresentados
os resultados obtidos com simula??es computacionais e os resultados obtidos com
ensaios do sistema implementado em laborat?rio. / Electrical disturbances such as voltage sags, interruptions and voltage unbalances
might cause serious problems for the end-user and for the companies of generation and
transmission of energy. Few years ago, those companies have been using methods and
equipments of protection to avoid the disturbances? presence or to mitigate their effects
on the power system. Disturbances generators are used to analyse the behavior of electrical
and electronic equipments affected by disturbances. The analysis of those failures
allows the development of appropriated protection equipments. In this paper, the development
of a disturbances generator based on power converters is presented. The disturbance
generator developed is able to generate some symmetrical disturbances, such as: voltage
sags, voltage swells and harmonic distortion. The control strategy used in the disturbance
generator is based on discrete and repetitive control. The steps of the design of the control
and of the filter used for reducing harmonic in the output, are detailed in the text. Are
presented the obtained results on computational simulations and the obtained results on
laboratory tests.
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Servi?o de nuvem p?blica e sua rela??o com os arranjos de governan?a de TI e o alinhamento estrat?gicoMendon?a, Cl?udio M?rcio Campos de 07 August 2015 (has links)
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Previous issue date: 2015-08-07 / Cada vez mais, a Tecnologia da Informa??o (TI) vem sendo utilizada para dar sustenta??o as estrat?gias de neg?cio, ocasionando aumento da sua relev?ncia. Por isso, a Governan?a de TI ? vista com uma das prioridades das organiza??es no momento. A busca pelo alinhamento estrat?gico entre neg?cio e TI ? debatida como um fator relevante para o sucesso empresarial, mas mesmo com essa import?ncia, normalmente os principais gestores de neg?cio relutam em assumir a responsabilidade das decis?es que envolvem a TI. Tudo isso, devido a complexidade de sua infraestrutura. J? a computa??o em nuvem vem sendo vista como um elemento capaz de auxiliar na implanta??o das estrat?gias organizacionais, em virtude de suas caracter?sticas permitirem uma maior efici?ncia e agilidade da ?rea de TI, sendo considerada como um novo paradigma computacional. O objetivo principal do estudo foi analisar as rela??es entre os arranjos de governan?a de TI e o alinhamento estrat?gico com a infraestrutura como servi?o (IaaS) da computa??o em nuvem p?blica. Para tanto, foi desenvolvida uma pesquisa explorat?ria, descritiva e inferencial com abordagem ao problema da pesquisa de forma quantitativa, utilizando o m?todo survey descritiva e de corte transversal. Foi utilizado um question?rio eletr?nico aplicado com os Associados do ISACA dos chapters do Estado de S?o Paulo e Distrito Federal, totalizando 164 respondentes. O instrumento utilizou como base as teorias de Weill e Ross (2006) para matriz de arranjo de governan?a de TI; Henderson e Venkatraman (1993) e Luftman (2000) para modelo de maturidade do alinhamento estrat?gico e NIST (2011 b), ITGI (2007) e CSA (2010) para maturidade da infraestrutura como servi?o (IaaS) p?blica em suas caracter?sticas essenciais. No tocante aos principais resultados, esta pesquisa comprovou que com a IaaS p?blica as estruturas de tomada de decis?o foram alteradas, havendo uma maior participa??o dos altos executivos em todas as cinco decis?es-chave de TI (matriz de arranjo de governan?a de TI), inclusive decis?es mais t?cnicas como arquitetura e infraestrutura de TI. Foi observada, tamb?m, a diminui??o na participa??o dos especialistas de TI, caracterizando-se o processo de decis?o com o arqu?tipo duop?lio (decis?o compartilhada). No quesito alinhamento estrat?gico foi observado que este ? alterado com a computa??o em nuvem, tendo as organiza??es com IaaS p?blica uma maturidade do alinhamento estrat?gico com diferen?a estatisticamente significativa e superior, quando comparada com as organiza??es sem IaaS. A maturidade da IaaS p?blica se encontra no n?vel intermedi?rio (n?vel 3 - ?processo definido?), tendo a elasticidade e mensura??o obtido o n?vel 4 - ?gerenciado e mensur?vel?. Diante disso, foi poss?vel inferir que nas organiza??es com IaaS p?blica h? correla??es entre as decis?es-chave e a maturidade da IaaS, principalmente em princ?pios, arquitetura e infraestrutura de TI e com os arqu?tipos que envolvem altos executivos e especialistas de TI, al?m da correla??o entre a maturidade do alinhamento estrat?gico e a maturidade da IaaS p?blica. Portanto, quanto maior o alinhamento estrat?gico, maior a maturidade da IaaS p?blica e vice-versa. / Increasingly, the Information Technology (IT) has been used to sustain the business
strategies, causing increased its relevance. Therefore IT governance is seen as one of the
priorities of organizations at the time. The search for strategic alignment between business
and IT is debated as a factor for business success, but even with that importance, usually the
main business managers are reluctant to take responsibility for decisions involving IT, mainly
due to the complexity of your infrastructure. Since cloud computing is being seen as an
element capable of assisting in the implementation of organizational strategies, because their
characteristics enable greater efficiency and agility in IT, and is considered as a new
computing paradigm. The main objective of the analyze the relationship between IT
governance arrangements and strategic alignment with the infrastructure as a service (IaaS) of
public cloud computing. Therefore, an exploratory, descriptive and inferential was developed,
with approach to the problem of quantitatively research, with descriptive survey method and
cross section. An electronic questionnaire that was applied to the ISACA chapters Associates
of S?o Paulo and the Distrito Federal, totaling 164 respondents was used. The instrument used
based on the theories of Weill and Ross (2006) for array of IT governance arrangement;
Henderson and Venkatraman (1993) and Luftman (2000), for maturity of the strategic
alignment model; and NIST (2011 b), ITGI (2007) and CSA (2010) for infrastructure maturity
as a service (IaaS) public in its essential characteristics. As regards the main results, this
research proved that with public IaaS decision-making structures have changed, with a greater
participation of senior executives in all five key IT decisions (IT governance arrangement
array) including more technical decisions as architecture and IT infrastructure. With increased
participation of senior executives the decrease was also observed in the share of IT specialists,
characterizing the decision process with the duopoly archetype (shared decision). With regard
to strategic alignment, it was observed that it changes with cloud computing, and
organizations with public IaaS, a maturity of strategic alignment with statistically significant
and greater difference when compared to organizations without IaaS. The maturity of public
IaaS is at the intermediate level (level 3 - "defined process"), with the elasticity and
measurement achieved level 4 - "managed and measurable" It was also possible to infer in
organizations with public IaaS, there are positive correlations between the key decisions and
the maturity of IaaS, especially at the beginning, architecture and infrastructure, and the
archetypes involving senior executives and IT specialists. In the correlation between the
maturity and mature strategic alignment of public IaaS therefore the higher the strategic
alignment, the greater the maturity of the public IaaS and vice versa.
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FTE-LEACH: um protocolo energeticamente eficiente e tolerante a falhas aplicado ?s redes industriais de sensores sem fioOliveira, Felipe Denis Mendon?a de 03 August 2015 (has links)
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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
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Modelagem dos efeitos da irradia??o luminosa no c?rebro de camundongos e rastreamento de neur?nios durante experimentos de microscopia de fluoresc?nciaPeixoto, Helton Maia 31 July 2015 (has links)
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Previous issue date: 2015-07-31 / As prote?nas fluorescentes constituem uma ferramenta fundamental em v?rios campos da biologia, pois permitem enxergar o desenvolvimento de estruturas e processos din?micos de c?lulas em tecido vivo, com o aux?lio da microscopia de fluoresc?ncia. A Optogen?tica ? outra t?cnica que atualmente ganha destaque na Neuroci?ncias e que, de forma geral, permite ativar/desativar neur?nios a partir da irradia??o luminosa de certos comprimentos de onda sobre as c?lulas que possuem canais i?nicos sens?veis ? luz, e ainda pode ser utilizada concomitantemente com as prote?nas fluorescentes. Esta tese possui dois objetivos principais. Inicialmente, s?o estudados os efeitos da intera??o da luz e o c?rebro de camundongos para aplica??es em experimentos de Optogen?tica. Nesta etapa, s?o modelados, a partir de caracter?sticas do c?rebro de camundongos e utilizando a teoria de Kulbelka-Munk, os efeitos de absor??o e espalhamento da luz, em comprimentos de onda espec?ficos, em fun??o da dist?ncia de penetra??o no tecido cerebral. Al?m disso, s?o modeladas as varia??es de temperatura utilizando o m?todo dos elementos finitos na resolu??o da equa??o de bioaquecimento de Pennes, com o aux?lio do COMSOL Multiphysics Modeling Software 4.4, onde s?o simulados protocolos de estimula??o luminosa, tipicamente utilizados em Optogen?tica. Posteriormente, s?o desenvolvidos algoritmos computacionais capazes de reduzir a exposi??o das c?lulas nervosas ? irradia??o luminosa necess?ria ? visualiza??o da fluoresc?ncia emitida por elas. Nesta etapa, s?o descritas as t?cnicas de processamento digital de imagens desenvolvidas para uso em microscopia de fluoresc?ncia, com o intuito de reduzir a exposi??o das amostras de c?rebro ? luz cont?nua, respons?vel pela excita??o dos fluorocromos. As t?cnicas de processamento de imagens desenvolvidas e utilizadas s?o capazes de rastrear, em tempo real, uma regi?o de interesse (ROI) e substituir a fluoresc?ncia emitida pelas c?lulas por uma m?scara virtual, como resultado da sobreposi??o da ROI que est? sendo rastreada e a informa??o de fluoresc?ncia previamente armazenada, mantendo a localiza??o das c?lulas independentemente do tempo de exposi??o ? luz fluorescente. Em resumo, esta tese pretende entender os efeitos da irradia??o luminosa no c?rebro, no contexto da Optogen?tica, al?m de fornecer uma ferramenta computacional que possa auxiliar certos experimentos em microscopia de fluoresc?ncia na redu??o do desvanecimento (bleaching) das amostras e dos danos (photodamage) causados ao tecido devido ? intensa exposi??o das estruturas fluorescentes ? luz. / The fluorescent proteins are an essential tool in many fields of biology, since they allow us to watch the development of structures and dynamic processes of cells in living tissue, with the aid of fluorescence microscopy. Optogenectics is another technique that is currently widely used in Neuroscience. In general, this technique allows to activate/deactivate neurons with the radiation of certain wavelengths on the cells that have ion channels sensitive to light, at the same time that can be used with fluorescent proteins. This dissertation has two main objectives. Initially, we study the interaction of light radiation and mice brain tissue to be applied in optogenetic experiments. In this step, we model absorption and scattering effects using mice brain tissue characteristics and Kubelka-Munk theory, for specific wavelengths, as a function of light penetration depth (distance) within the tissue. Furthermore, we model temperature variations using the finite element method to solve Pennes? bioheat equation, with the aid of COMSOL Multiphysics Modeling Software 4.4, where we simulate protocols of light stimulation tipically used in optogenetics. Subsequently, we develop some computational algorithms to reduce the exposure of neuron cells to the light radiation necessary for the visualization of their emitted fluorescence. At this stage, we describe the image processing techniques developed to be used in fluorescence microscopy to reduce the exposure of the brain samples to continuous light, which is responsible for fluorochrome excitation. The developed techniques are able to track, in real time, a region of interest (ROI) and replace the fluorescence emitted by the cells by a virtual mask, as a result of the overlay of the tracked ROI and the fluorescence information previously stored, preserving cell location, independently of the time exposure to fluorescent light. In summary, this dissertation intends to investigate and describe the effects of light radiation in brain tissue, within the context of Optogenetics, in addition to providing a computational tool to be used in fluorescence microscopy experiments to reduce image bleaching and photodamage due to the intense exposure of fluorescent cells to light radiation.
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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 projectsOliveira, R?mulo Alves de 27 January 2015 (has links)
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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.
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