10 research outputs found
Absolute Continuity of Solutions to Reaction-Diffusion Equations with Multiplicative Noise
We prove absolute continuity of the law of the solution, evaluated at fixed points in time and space, to a parabolic dissipative stochastic PDE on L (G), where G is an open bounded domain in ℝ with smooth boundary. The equation is driven by a multiplicative Wiener noise and the nonlinear drift term is the superposition operator associated to a real function that is assumed to be monotone, locally Lipschitz continuous, and growing not faster than a polynomial. The proof, which uses arguments of the Malliavin calculus, crucially relies on the well-posedness theory in the mild sense for stochastic evolution equations in Banach spaces. 2
Non elliptic SPDEs and ambit fields: existence of densities
Relying on the method developed in [debusscheromito2014], we prove the
existence of a density for two different examples of random fields indexed by
(t,x)\in(0,T]\times \Rd. The first example consists of SPDEs with Lipschitz
continuous coefficients driven by a Gaussian noise white in time and with a
stationary spatial covariance, in the setting of [dalang1999]. The density
exists on the set where the nonlinearity of the noise does not vanish.
This complements the results in [sanzsuess2015] where is assumed to be
bounded away from zero. The second example is an ambit field with a stochastic
integral term having as integrator a L\'evy basis of pure-jump, stable-like
type.Comment: 23 page
Weak convergence of finite element approximations of linear stochastic evolution equations with additive noise II. Fully discrete schemes
We present an abstract framework for analyzing the weak error of fully
discrete approximation schemes for linear evolution equations driven by
additive Gaussian noise. First, an abstract representation formula is derived
for sufficiently smooth test functions. The formula is then applied to the wave
equation, where the spatial approximation is done via the standard continuous
finite element method and the time discretization via an I-stable rational
approximation to the exponential function. It is found that the rate of weak
convergence is twice that of strong convergence. Furthermore, in contrast to
the parabolic case, higher order schemes in time, such as the Crank-Nicolson
scheme, are worthwhile to use if the solution is not very regular. Finally we
apply the theory to parabolic equations and detail a weak error estimate for
the linearized Cahn-Hilliard-Cook equation as well as comment on the stochastic
heat equation
Nonlinear stochastic evolution equations of second order with damping
Convergence of a full discretization of a second order stochastic evolution
equation with nonlinear damping is shown and thus existence of a solution is
established. The discretization scheme combines an implicit time stepping
scheme with an internal approximation. Uniqueness is proved as well.Comment: This is the version of the article accepted for publication. The
final publication is available at http://link.springer.co
Teacher’s formation: Between the “aestheticization” that affirms life, as it is, and the “rationalization” that denies it
v.13, n. 2, p. 44-65, jul./dez. 2015.Submitted by Marlene Santos ([email protected]) on 2016-03-08T20:38:09Z
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Previous issue date: 2015-11-10Programa de Apoio à Publicações Periódicas Científicas (PROAPUPEC) da UFGO autor utiliza o pensamento de Nietzsche e de comentaristas, além de alguns
filósofos da educação brasileira, como referências teóricas para analisar o que chamou de
“a decadência da formação de professores, no Brasil”. Inicia sua análise no período
mítico-trágico dos gregos antigos, época de uma cultura estética e afirmadora da vida e
analisa o processo de ruptura, que silencia a cultura trágica e estética e dá voz à cultura
racional que emerge, sobretudo com Platão, Paulo de Tarso e Agostinho. Com este último,
a “metafísica cristã” se institucionaliza como laudatória do catolicismo em direção a toda
Europa medieval, além de outros povos. O autor situa na ruptura mencionada a origem
do ressentimento ou da reatividade que são dois fenômenos culturais que fundamentam o
que ele chamou “Pedagogia do Ressentimento”, ou seja, um discurso pedagógico reativo,
responsável, no entendimento do autor, pela decadência do processo de formação de
professores.El autor utiliza Nietzsche y comentaristas, así como filósofos de la educación
brasileña, y las referencias teóricas para el análisis de la “decadencia de la formación
docente en Brasil”. Parte del período mítico y trágico de los antiguos griegos, el tiempo
de una cultura estética y analiza el proceso de ruptura, que silencia la cultura y la estética
trágica y da voz a la cultura racional emergente, especialmente con Platón, Pablo de Tarso
y Agustín. Con este último, la "metafísica cristiana" está institucionalizada em el
catolicismo y em su laudatoria hacia por toda la Europa medieval, y otras naciones. El
autor el autor analiza, geneologicamente, el “ resentimiento” o la “reactividad” que son
dos fenómenos culturales que subyacen a lo que él llamó "Pedagogía del Resentimiento",
es decir, un discurso pedagógico reactivo, piadoso y redentor, responsable, en opinión del
autor, por el proceso de descomposición em la educación y em la formación del
profesorado.The author uses Nietzsche and commentators, as well as philosophers of
Brazilian education, as a theoretical framework to analyze the decay of teacher formation
in Brazil. First of all, he analyzes the mythic-tragic period of the ancient Greeks, the time
of an aesthetic culture and life-affirming. Then, he describes the process of rupture toward
the rational and emerging culture, moment that he emphasizes thinkers as Plato, Paul of
Tarsus and Augustine. Thus, the metaphysical-Christian’ culture is institutionalized as
Catholicism’s laudatory and reaches all Europe and its colonized peoples. The
“resentment” or “reactivity” is located in this breakdown between two cultures and two
diferente conceptions of formation, This reactivity created what the author understands
as a "Pedagogy of Resentment" and its reactive pedagogical’s discourse which is
responsable, according to the author, for the decline of this teacher’s formation in Brazil