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O ensino de ciências nos anos iniciais: sinalizando possibilidades de mudanças
(Universidade Federal de Santa Maria, 2012-12-17)
This current study s general idea was to investigate what students from the first
years of school were aware regarding Science and if such conceptions could differ
among teachers and students. After, it was intended to ...
Contribuições ao acionamento e controle sensorless aplicado ao motor de indução bifásico assimétrico
(Universidade Federal de Santa Maria, 2012-05-11)
This doctoral thesis presents the development of sensorless methods aiming the rotor
speed control of asymmetrical two-phase induction motors. Initially, the machine mathematical
model is presented. From the machine model, ...
Desenvolvimento de uma família de reatores eletrônicos para lâmpadas fluorescentes sem eletrodos empregando a técnica de integração de conversores
(Universidade Federal de Santa Maria, 2012-11-30)
This paper presents the design and development of an electronic ballasts family
obtained through the use of the integration technique of converters for feeding the
electrodeless fluorescents lamps (EFL). This type of lamp ...
Dinâmica da vegetação em remanescente de floresta estacional subtropical
(Universidade Federal de Santa Maria, 2012-01-12)
The aim of this work was to study vegetation groupings and their dynamics in
remnant of Subtropical Seasonal Forest, of nearly 560 ha, located at the Instruction
Field of Santa Maria, in Santa Maria municipality, RS. In ...
Estimativa do desempenho de tratores agrícolas em campo e pista a partir do ensaio dinamométrico
(Universidade Federal de Santa Maria, 2012-03-22)
The agricultural tractor allows to move and to pull machines and implements used
during the execution of the activities to field. One of the largest problem refers to
the acting of the tractor, the reason of a lot of ...
Contribuição ao estudo anatômico das Myrtaceae nativas no Rio Grande do Sul
(Universidade Federal de Santa Maria, 2012-03-06)
Myrtaceae is one of the most important botanical families, either in diversity and species abundance, in different forest types on Rio Grande do Sul State, Brazil. Very complex from the taxonomic point of view, this family ...
Investigação teórica sobre possíveis aplicações na eletrônica de nanofios de AlN, GaN e InN: um estudo de primeiros princípios
(Universidade Federal de Santa Maria, 2012-07-30)
Using the formalism of Density Functional Theory with spin polarization and the Generalized
Gradient Approximation for exchange and correlation term, we studied the stability
and electronic properties of substitutional ...
Susceptibilidade magnética de um modelo de Hubbard estendido com interação ao atrativa
(Universidade Federal de Santa Maria, 2012-01-17)
Anomalous properties of the normal state of a strongly correlated electron system described
by an attractive extended Hubbard model are investigated. The equations of motion
of the Green s functions are calculated with the ...
Derivação de coeficientes de difusão turbulenta em condições de vento norte: aplicação em um modelo analítico euleriano de dispersão de poluentes
(Universidade Federal de Santa Maria, 2012-06-15)
The advection-diffusion equation has been extensively used in air pollution models to simulate mean contaminant concentrations in the planetary boundary layer (PBL). Therefore, in a Eulerian framework, it is possible to ...
Dinâmica da transição pré-câncer para câncer: estudo da expressão de vias de manutenção do genoma
(Universidade Federal de Santa Maria, 2012-07-09)
The loss of genomic stability associated with genetic deterioration is one of the many important aspects for the development of carcinomas. The genome maintenance mechanisms (GMM) ensure the integrity of DNA and cell ...