Surface potentials of corona-charged ferroelectric P(VDF-TrFE) copolymer samples

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

THREE TIME SCALE SINGULAR PERTURBATION PROBLEMS AND NONSMOOTH DYNAMICAL SYSTEMS

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

On symmetries of singular implicit ODEs

We study implicit ODEs, cubic in derivative, with infinitesimal symmetry at singular points. Cartan showed that even at regular points the existence of nontrivial symmetry imposes restrictions on the ODE. Namely, this algebra has the maximal possible dimension 3 iff the web of solutions is flat. For cubic ODEs with flat 3-web of solutions we establish sufficient conditions for the existence of nontrivial symmetries at singular points and show that under natural assumptions such a symmetry is semi-simple, i.e. is a scaling is some coordinates. We use this symmetry to find first integrals of the ODE.

Local classification of singular hexagonal 3-webs with holomorphic Chern connection form and infinitesimal symmetries

Implicit ODE, cubic in derivative, generically has no infinitesimal symmetries even at regular points with distinct roots. Cartan showed that at regular points, ODEs with hexagonal 3-web of solutions have symmetry algebras of the maximal possible dimension 3. At singular points such a web can lose all its symmetries. In this paper we study hexagonal 3-webs having at least one infinitesimal symmetry at singular points. In particular, we establish sufficient conditions for the existence of non-trivial symmetries and show that under natural assumptions such a symmetry is semi-simple, i.e. is a scaling in some coordinates. Using the obtained results, we provide a complete classification of hexagonal singular 3-web germs in the complex plane, satisfying the following two conditions: 1) the Chern connection form is holomorphic at the singular point, 2) the web admits at least one infinitesimal symmetry at this point. As a by-product, a classification of hexagonal weighted homogeneous 3-webs is obtained.

Geometric singular perturbartion theory for non-smooth dynamical systems

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

Singular value analyses of voltage stability on power system considering wind generation variability

Pós-graduação em Engenharia Elétrica - FEIS

Three-body Faddeev calculation for 11Li with separable potentials

The halo nucleus 11Li is treated as a three-body system consisting of an inert core of 9Li plus two valence neutrons. The Faddeev equations are solved using separable potentials to describe the two-body interactions, corresponding in the n-9Li subsystem to a p1/2 resonance plus a virtual s-wave state. The experimental 11Li energy is taken as input and the 9Li transverse momentum distribution in 11Li is studied. [S0556-2813(99)01703-3].

Dynamical algebra of quasi-exactly-solvable potentials

We show that by using second-order differential operators as a realization of the so(2,1) Lie algebra, we can extend the class of quasi-exactly-solvable potentials with dynamical symmetries. As an example, we dynamically generate a potential of tenth power, which has been treated in the literature using other approaches, and discuss its relation with other potentials of lowest orders. The question of solvability is also studied. © 1991 The American Physical Society.

Os desenhos da cidade observada: uma reflexão singular

How are teachers Cartoons observation Architecture Schools in several decades, the idea was to try and explain firsthand the look and fundamental elements of drawings to the Architect. We start looking through the design of: 1 A projective gaze: the invisible is made visible by interactivity and space and time are perceived by the distance that look place between them; 2nd In bidirectional contamination: the object fills the subject, double-hand, bringing the tactile qualities of architecture in continuous resonance, 3rd Strangeness by slow look: draw as perceptual expansion strategy; 4 Articulation of the structural elements of the design while similar language to architecture and city through the selection of appropriate signs and codes, exclusive and singular.

A dialética singular-particular-universal: implicações do método materialista dialético para a psicologia

Considering that Cultural-Historical theory has been gaining importance within Brazilian Psychology in the last decades, this essay aims at contributing to understanding its ontological and epistemological foundations, introducing the concepts of singularity, particularity and universality of the dialectics that exists between them. The analysis looks to explore the implications to Psychology, both as a science and as a professional practice, of the lukacsian indication about the need to apprehend the connections between singularity, particularity and universality as a condition for understanding the essence of phenomena. In that sense, this analysis brings light to the individual/society dynamics unity affirmed by historical-dialectical materialism, which contributes to overcoming of the dichotomies usually established between the poles of this relationship.

Autismo: aspectos cognitivos, educacionais e neurobiológicos com base na análise dos livros Mundo singular: entenda o autismo e o Os gatos nunca mentem sobre o amor e na literatura especializada

The autism is a severe mental illness that involves psychological, social, educational and neurobiological aspects. The Education plays an important role in recovering, preserving and increasing the cognitive task of people with autism. There are several ways to observe a person with autism. Through the studying of cases, it is also possible to address issues of everyday life of the person with the illness, its cognitive issues and its obstacles of psychosocial involvement, as well as psychological aspects such as illness acknowledgement. Through specialized literature, it is possible to identify characteristics referring to the learning process and neurobiological components involved in the condition, such as brain activity disorder and genetic factors. The objectives of this paper are: from the analysis of two books: Unique World: comprehend the Autism (SILVA, A. B. B; GAIATO, M.B; REVELES, L.T) and The cats never lie about love (DILLON, J.), it is intended to describe cognitive and psychosocial aspects of the autism. Based on the specialized literature, the goal is to identify cognitive and neurobiological components in the illness. The methods that were used: analysis of the books Unique World: comprehend the Autism and The cats never lie about love to describe psychosocial and educational aspects of the autism; analysis of the specialized literature to identify clinical and neurobiological components of the illness, such as changes in brain activity, genetic factors or clinical evolution; and also details of the Education role in preserving the person with autism and his cognitive and emotional development. The study had the documentary research as reference for the methodological design, including book analysis and research in specialized literature. It is intended to deepen discussions about the Education roles related to the cognitive and neurobiological aspects of the autism

Osmotic potentials on water uptake and germination of Guazuma ulmifolia Lam. (Sterculiaceae) seeds

Osmotic potentials on water uptake and germination of Guazuma Ulmifolia Lam. (Sterculiaceae) seeds. This work was carried out in the Germination Lab. of the Department of Botany, Institute of Biosciences, São Paulo State University (UNESP), Botucatu, São Paulo State, Brazil. The aims of this work were to determine the water uptake curve and to evaluate the germination of Guazuma ulmifolia seeds subjected to different water potentials. For the water uptake curve, seven replicates of 50 pre-scarified seeds were placed onto paper moistened with 15 mL PEG 6000 solution under the potentials 0 (control), -0.3 and -0.6 MPa at 25o C in the darkness. For the germination assay, four replicates of 50 seeds were subjected to the same above-described conditions; however, one lot of seeds was modified when there was variation in the refractometric index, whereas the remaining ones were kept in the same solutions until the end of the experiment. All three phases of water uptake were detected under 0 and -0.3 MPa; however, phase II was prolonged under -0.6 MPa and germination was not observed. For 0 and -0.3 MPa, the adopted statistical models consisted of asymptotic (phases I and II) and exponential (phase III) functions, y = a*[1 - b*exp (-c*t) + exp (-d + e*(t - t0)]. For -0.6MPa, only the asymptotic function y = a* [1 - b* exp (-c*t)] was used since there was no evidence of germination. The germination final percentage and speed index were lower under -0.3 MPa, mainly when solutions were not replaced; besides, germination was not detected under -0.6 MPa, with or without solution replacement.

Applications and Potentials for Biogenic Methane Recovery Operations in Nebraska Agriculture, Industry, and Economic Development

ABSTRACT: This thesis report illustrates the applications and potentials of biogenic methane recovery in Nebraska’s agricultural and industrial sectors and as a means for increasing sustainable economic development in the state’s rural communities. As the nation moves toward a new green economy, biogenic methane recovery as a waste management strategy and renewable energy resource presents significant opportunities for Nebraska to be a national and world leader in agricultural and industrial innovation, advanced research and development of renewable energy technology, and generation of new product markets. Nebraska’s agricultural economy provides a distinct advantage to the state for supporting methane recovery operations that provide long-term economic and environmental partnerships among producers, industry, and communities. These opportunities will serve to protect Nebraska’s agricultural producers from volatile energy input markets and as well as creating new markets for Nebraska agricultural products. They will also serve to provide quality education and employment opportunities for Nebraska students and businesses. There are challenges and issues that remain for the state in order to take advantage of its resource potential. There is a need to produce a comprehensive Nebraska biogenic methane potential study and digital mapping system to identify high-potential producers, co-products, and markets. There is also a need to develop a web-based format of consolidated information specific to Nebraska to aid in connecting producers, service providers, educators, and policy-makers.

Continuity of Dynamical Structures for Nonautonomous Evolution Equations Under Singular Perturbations

In this paper we study the continuity of invariant sets for nonautonomous infinite-dimensional dynamical systems under singular perturbations. We extend the existing results on lower-semicontinuity of attractors of autonomous and nonautonomous dynamical systems. This is accomplished through a detailed analysis of the structure of the invariant sets and its behavior under perturbation. We prove that a bounded hyperbolic global solutions persists under singular perturbations and that their nonlinear unstable manifold behave continuously. To accomplish this, we need to establish results on roughness of exponential dichotomies under these singular perturbations. Our results imply that, if the limiting pullback attractor of a nonautonomous dynamical system is the closure of a countable union of unstable manifolds of global bounded hyperbolic solutions, then it behaves continuously (upper and lower) under singular perturbations.

Anderson-like Transition for a Class of Random Sparse Models in d >= 2 Dimensions

We show that the Kronecker sum of d >= 2 copies of a random one-dimensional sparse model displays a spectral transition of the type predicted by Anderson, from absolutely continuous around the center of the band to pure point around the boundaries. Possible applications to physics and open problems are discussed briefly.