Experimental analysis of harmonic distortions in the excitation currents of double-excited three-phase transformers

This paper shows the results of experimental investigations of three-phase banks composed of single-phase transformers and three-phase three-limb core transformers under simultaneous alternating and direct current excitations, for several winding connections. Harmonic analysis of excitation currents for different de saturation levels is performed.

double-struck D signn-forced symmetry breaking of double-struck O sign (2)-equivariant problems

We use singularity theory to classify forced symmetry-breaking bifurcation problems f(z, λ, μ) = f1 (z, λ) + μf2(z, λ, μ) = 0, where f1 is double-struck O sign (2)-equivariant and f2 is double-struck D sign n-equivariant with the orthogonal group actions on z ∈ ℝ2. Forced symmetry breaking occurs when the symmetry of the equation changes when parameters are varied. We explicitly apply our results to the branching of subharmonic solutions in a model periodic perturbation of an autonomous equation and sketch further applications.

Composition of stingless bee honey: Setting quality standards

Compositional data from 152 stingless bee (Meliponini) honey samples were compiled from studies since 1964, and evaluated to propose a quality standard for this product. Since stingless bee honey has a different composition than Apis mellifera honey, some physicochemical parameters are presented according to stingless bee species. The entomological origin of the honey was known for 17 species of Meliponini from Brazil, one from Costa Rica, six from Mexico, 27 from Panama, one from Surinam, two from Trinidad & Tobago, and seven from Venezuela, most from the genus Melipona. The results varied as follows: moisture (19.9-41.9g/100g), pH (3.15-4.66), free acidity (5.9-109.0meq/Kg), ash (0.01-1.18g/100g), diastase activity (0.9-23.0DN), electrical conductivity (0.49-8.77mS/cm), HMF (0.4-78.4mg/Kg), invertase activity (19.8-90.1IU), nitrogen (14.34-144.00mg/100g), reducing sugars (58.0-75.7g/100g) and sucrose (1.1-4.8g/100g). Moisture content of stingless bee honey is generally higher than the 20% maximum established for A. mellifera honey. Guidelines for further contributions would help make the physicochemical database of meliponine honey more objective, in order to use such data to set quality standards. Pollen analysis should be directed towards the recognition of unifloral honeys produced by stingless bees, in order to obtain standard products from botanical species. A honey quality control campaign directed to both stingless beekeepers and stingless bee honey hunters is needed, as is harmonization of analytical methods. © 2007 Asociación Interciencia.

Negative Even Grade mKdV Hierarchy and its Soliton Solutions

In this paper we discuss the algebraic construction of the mKdV hierarchy in terms of an affine Lie algebra (s) over capl(2). An interesting novelty araises from the negative even grade sector of the affine algebra leading to nonlinear integro-differential equations admiting non-trivial vacuum configuration. These solitons solutions are constructed systematically from generalization of the dressing method based on non zero vacua. The sub-hierarchies admiting such class of solutions are classified.

Methodology for load compensation in four-wire electrical power systems based on instantaneous sampling

This work describes a methodology for power factor control and correction of the unbalanced currents in four-wire electric circuits. The methodology is based on the insertion of two compensation networks, one wye-grounded neutral and other in delta, in parallel to the load. The mathematical development has been proposed in previous work [3]. In this paper, however, the determination of the compensation susceptances is based on the instantaneous values of load currents. The results are obtained using the MatLab-Simulink enviroment

A note on non-degenerate umbilics and the path formulation for bifurcation problems

Path formulation can be used to classify and structure efficiently multiparameter bifurcation problems around fundamental singularities: the cores. The non-degenerate umbilic singularities are the generic cores for four situations in corank 2: the general or gradient problems and the ℤ 2-equivariant (general or gradient) problems. Those categories determine an interesting 'Russian doll' type of structure in the universal unfoldings of the umbilic singularities. One advantage of our approach is that we can handle one, two or more parameters using the same framework (even considering some special parameter structure, for instance, some internal hierarchy). We classify the generic bifurcations that occur in those cases with one or two parameters.

O demonio renitente: demonologia e colonização no vice reinado do Peru, séculos XVI e XVII

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A importância da observação da estrutura textual durante a catalogação de assunto de livros científicos em bibliotecas universitárias: uma análise realizada a partir da técnica de Protocolo Verbal

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O exercício anticompetitivo da propriedade intelectual de plantas na Argentina e no Brasil: um estudo sobre a interface entre comércio internacional e política de concorrência

Pós-graduação em Direito - FCHS

(In)capacitados para o trabalho?: trabalho, estranhamento e saúde do trabalhador no Brasil (2000-2010)

Pós-graduação em Ciências Sociais - FFC

A terapia morfoanalítica como recurso terapêutico em mulheres pós-cirurgia de câncer de mama

Pós-graduação em Fisioterapia - FCT

Análise da dinâmica de preços entre os mercados futuros de grão, farelo e óleo de soja na China e Estados Unidos

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Tributação do comércio eletrônico e integração regional

Pós-graduação em Direito - FCHS

O paradigmático caso do processo às juntas militares argentinas

This article analyzes the case of the proceedings against Argentina’s Military Juntas that led to jail those responsible for heinous crimes committed during the military dictatorship. The said proceeding has a high symbolic value in the struggle for human rights in Latin America and is relevant and timely in Brazil where the right to the truth regarding the missing people during the military dictatorship is in debate, as well as the invalidation of the Amnesty Act regarding the common crimes of torture, rape and / or kidnapping, among others. In the case of Argentina, following Roxin’s doctrine of mediate authorship, the Court held that the crimes were committed by the military through the use of an organized power apparatus and emphatically dismissed allegations that such crimes were justified in the so-called “dirty war”. Thus, the case against the Military Juntas has become a paradigmatic one, not only in Argentina, where many military leaders had to respond to criminal actions, but for all countries in the region that faced similar situations in recent history.

A tempestividade da prestação da tutela jurisdicional como requisito essencial à efetividade do direito

Pós-graduação em Direito - FCHS