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Genética dos teores de fósforo e de zinco em sementes de feijão
(Universidade Federal de Santa Maria, 2009-08-24)
The common bean (Phaseolus vulgaris L.) stands out as an important source of phosphorus and zinc in for human consumption. Therefore, the legume can be used to reduce
the risk of deficiency of phosphorus and zinc and to ...
Tempo de implantação do sistema plantio direto e propriedades físico-mecânicas de um latossolo
(Universidade Federal de Santa Maria, 2009-12-23)
Which the effect of no-tillage system on the soil physical and mechanical properties along the time? With this question, the objective this study was to evaluate the effect of the no-tillage system along the time on the ...
Estudo, controle e implementação do conversor Boost PFC operando no modo de condução mista
(Universidade Federal de Santa Maria, 2009-11-10)
This Master Thesis presents the study and proposes a digital control system applied to the PFC boost converter operating in mixed conduction mode. The motivation to this subject, a bibliographic review of the existing ...
Tranformada wavelet e redes neurais artificiais na análise de sinais relacionados à qualidade da energia elétrica
(Universidade Federal de Santa Maria, 2009-02-10)
This work presents a different method for power quality signal classification using the principal components analysis (PCA) associated to the wavelet transform (WT). The standard deviation of the detail coefficients and ...
Integração de pilhas de células a combustível com outras fontes alternativas de energia
(Universidade Federal de Santa Maria, 2009-03-31)
This dissertation presents a project of a integrated system with distinct energy generating modules using a wind generator, photovoltaic generator, fuel cells stack
(FCs) and an accumulator of energy formed by a bank of ...
Contribuição ao estudo de estratégias de modulação aplicadas a conversores multiníveis com diodos de grampeamento
(Universidade Federal de Santa Maria, 2009-04-30)
This dissertation deals with modulation techniques for multilevel diode clamped converters.
The major challenge to be overcome by modulation strategies to these converters
is the balance of the dc-link voltage capacitors, ...
Métodos para otimização dos ajustes dos reguladores de tensão e zonas de tap em sistemas de distribuição
(Universidade Federal de Santa Maria, 2009-08-07)
The new regulations in the electric sector utilities have have requested greater efficiency and quality both in terms of continuity and in conformity of the energy
supplied. Electrical equipments quality, efficiency and ...
Análise comparativa de conversores monofásicos aplicados a correção de fator de potência
(Universidade Federal de Santa Maria, 2009-08-12)
This work presents a study and a comparative analysis of high power single-phase converter applied to power factor correctioii in according to the international standards IEC
61000-3-4 (harmonics limitation) and CISPR 22 ...
Uma nova metodologia de projeto para otimização do volume do converosr boost PFC
(Universidade Federal de Santa Maria, 2009-03-27)
This work investigates the influence of operation point (Δi @ fs) in the final volume of PFC boost converter. The boost inductor, EMI filter and thermal heatsink are the elements which main influences in the converter ...
A musculatura epaxial e a fibrose epidural na compressão medular em cães submetidos à laminectomia dorsal modificada
(Universidade Federal de Santa Maria, 2009-03-03)
The purpose of this study was to isolate the adjacent epaxial musculature from exposed spinal cord by modified dorsal laminectomy in dogs with aluminum implant
and whether the muscles contribute to form fibrosis epidural ...