Canonical Transformation
Mostrando 1-12 de 32 artigos, teses e dissertações.
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1. Drivers of floristic variation in biogeographic transitions: insights from the ecotone between the largest biogeographic domains of South America
ABSTRACT Ecological transitions usually represent vulnerable ecosystems and high biodiversity. Investigating their drivers is important from both biogeographic and conservationist perspectives. One of these transitions is situated between the two largest biogeographic domains of South America - the Amazon and the Cerrado. We evaluated variation in tree flori
Acta Bot. Bras.. Publicado em: 2020-03
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2. Analytical Solution for Optimal Low-Thrust Limited-Power Transfers Between Non-Coplanar Coaxial Orbits
ABSTRACT: In this paper, an analytical solution for time-fixed optimal low-thrust limited-power transfers (no rendezvous) between elliptic coaxial non-coplanar orbits in an inverse-square force field is presented. Two particular classes of maneuvers are related to such transfers: maneuvers with change in the inclination of the orbital plane and maneuvers wit
J. Aerosp. Technol. Manag.. Publicado em: 03/05/2018
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3. Geração automática de código para a execução em um ambiente de computação em DataFlow
The computers architectures are becoming more distributed and hierarchical,that is, there exist lots of computers in a cluster and there are many processors in these computers and these processors have multiple cores. Many models have been proposed to explore the features of the computers architectures. The Data-flow computing models stand out among the prop
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 18/10/2010
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4. A ruptura da narratividade tradicional nas cenas enunciativas das canÃÃes do tropicalismo / The breach of tradicional narrative in the enunciative scenes of tropicalism songs
This work aims at showing how the tropicalist text breaks with the structure of traditional texts. For that purpose, we characterize the traditional narrativity and show how this rupture happens in the tropicalist positioning through the description of the procedures used in the non-structuring process of tropicalist texts as well as the factors that create
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/08/2010
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5. Análogos cosmológicos dos efeitos Schwinger estático e oscilatório / Cosmological Analogues of the Static and Oscillatory Schwinger Effect
In this work we study the quantum effects of particle creation in the cosmological context and of the classical electrodynamics. With the studies of the particle creation in constant and oscillatory external electrical fields, the known static and oscillatory Schwinger effects, respectively, it was possible to study the polarization of the quantum vacuum and
Publicado em: 2009
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6. Optimal low thrust limited power transfers between arbitrary elliptic orbits. / Transferências ótimas a baixo empuxo e potência limitada entre órbitas elípticas quaisquer
Neste trabalho é apresentada uma análise do problema de transferências espaciais ótimas entre órbitas coplanares e coaxiais diretas, entre órbitas coplanares não coaxiais diretas e entre órbitas não-coplanares coaxiais diretas em campo central Newtoniano, realizadas através de sistemas propulsivos a baixo empuxo e potência limitada. O problema ger
Publicado em: 2004
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7. Transferências ótimas a baixo empuxo e potência limitada entre órbitas elípticas quaisquer / Optimal low thrust limited power transfers between arbitrary elliptic orbits.
Neste trabalho é apresentada uma análise do problema de transferências espaciais ótimas entre órbitas coplanares e coaxiais diretas, entre órbitas coplanares não coaxiais diretas e entre órbitas não-coplanares coaxiais diretas em campo central Newtoniano, realizadas através de sistemas propulsivos a baixo empuxo e potência limitada. O problema ger
Publicado em: 2004
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8. Leitura na formação de professores de inglês da rede pública: a questão da reprodução de leitura no ensino de inglês / Reading in training of teachers for english in public network: the issue of reproduction of reading in the teaching of english
The main aim of this study is to investigate how some of the subjects involved in the process of the teaching of English, as a foreign language, develop and practice their critical sense in this teaching. Due to the preliminary results of this investigation, a phase known as process of rupture which consists of deconstructing and subverting interpretations c
Publicado em: 2004
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9. Universal closed-form of lagrangian multipliers for coast-arcs of optimum space trajectories
An universal closed-form solution of Lagrangian multipliers for the coast-arcs of optimum space trajectories in a Newtonian central force field is obtained by means of properties of generalized canonical systems and Sundman transformation. This closed-form solution, valid for all conics, is given as a function of a generalized anomaly.
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2003-12
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10. Circulant orbitals for atoms and molecules
Circulant orbitals ϕn for a closed-shell system are the orbitals obtained when the N canonical orthonormal Hartree-Fock orbitals λ[unk] are subjected to a unitary transformation which is the discrete Fourier transformation: ϕn = 1/√N Σ[unk]λ[unk]ω(n-1)([unk]-1), where ω = exp(2πi/N). Electron densities associated with the orbitals ϕn are each clos
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11. Dynamics of Systems with Large Number of Degrees of Freedom and Generalized Transformation Theory*
A generalized transformation theory which leads to a non-Hamiltonian description of dynamics is introduced. The transformation is such that all averages of observables remain invariant. However, the time evolution of the density matrix can no longer be expressed in terms of a commutator with the Hamiltonian. Therefore such transformations are not canonical i
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12. A Biological Least-Action Principle for the Ecological Model of Volterra-Lotka
The conservative model of Volterra for more-than-two predator-prey species is shown to be generated as extremals that minimize a definable Lagrange-Hamilton integral involving half the species and their rates of change. This least-action formulation differs from that derived two generations ago by Volterra, since his involves twice the number of phase variab