Non-Markovian expansion in quantum Brownian motion

We consider the non-Markovian Langevin evolution of a dissipative dynamical system in quantum mechanics in the path integral formalism. After discussing the role of the frequency cutoff for the interaction of the system with the heat bath and the kernel and noise correlator that follow from the most common choices, we derive an analytic expansion for the exact non-Markovian dissipation kernel and the corresponding colored noise in the general case that is consistent with the fluctuation-dissipation theorem and incorporates systematically non-local corrections. We illustrate the modifications to results obtained using the traditional (Markovian) Langevin approach in the case of the exponential kernel and analyze the case of the non-Markovian Brownian motion. We present detailed results for the free and the quadratic cases, which can be compared to exact solutions to test the convergence of the method, and discuss potentials of a general nonlinear form. © 2013 Elsevier B.V. All rights reserved.

Tm-afm nonlinear motion control with robustness analysis to parametric errors in the control signal determination

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effects of physical exercise on articular range of motion of the lower limb in the Parkinson's disease individuals

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

TACTILE CARTOGRAPHY EXPERIENCES IN BRAZIL: METHODOLOGIES AND DIDACTICAL MATERIAL WITH TECHNOLOGICAL RESOURCES FOR INCLUSION OF BLIND AND LOW VISION STUDENTS

The tactile cartography is an area of Cartography that aims the development of methodologies and didactical material to work cartographic concepts with blind and low vision people. The main aim of this article is to present the experience of Tactile Cartography Research Group from Sao Paulo State University (UNESP), including some didactical material and courses for teachers using the System MAPAVOX. The System MAPAVOX is software developed by our research group in a partnership with Federal University of Rio de Janeiro (UFRJ) that integrates maps and models with a voice synthesizer, sound emission, texts, images and video visualizing for computers. Our research methodology is based in authors that have in the students the centre of didactical activity such as Ochaita and Espinosa in [1], which developed studies related to blind children's literacy. According to Almeida the child's drawing is, thus, a system of representation. It isn't a copy of objects, but interpretation of that which is real, done by the child in graphic language[2]. In the proposed activities with blind and low vision students they are prepared to interpret reality and represent it by adopting concepts of graphic language learned. To start the cartographic initialization it is necessary to use personal and quotidian references, for example the classroom tactile model or map, to include concepts in generalization and scale concerning to their space of life. During these years many case studies were developed with blind and low vision students from Special School for Hearing Impaired and Visually Impaired in Araras and Rio Claro, Sao Paulo - Brazil. The most part of these experiences and others from Brazil and Chile are presented in [3]. Tactile material and MAPAVOX facilities are analysed by students and teachers who contribute with suggestions to reformulate and adapt them to their sensibility and necessity. Since 2005 we offer courses in Tactile Cartography to prepare teachers from elementary school in the manipulation of didactical material and attending students with special educational needs in regular classroom. There were 6 classroom and blended courses offered for 184 teachers from public schools in this region of the Sao Paulo state. As conclusion we can observe that methodological procedures centred in the blind and low vision students are successful in their spatial orientation if use didactical material from places or objects with which they have significant experience. During the applying of courses for teachers we could see that interdisciplinary groups can find creative cartographic alternatives more easily. We observed too that the best results in methodological procedures were those who provided concreteness to abstract concepts using daily experiences.

Preventing chaotic motion in tapping-mode atomic force microscope

During the last 30 years the Atomic Force Microscopy became the most powerful tool for surface probing in atomic scale. The Tapping-Mode Atomic Force Microscope is used to generate high quality accurate images of the samples surface. However, in this mode of operation the microcantilever frequently presents chaotic motion due to the nonlinear characteristics of the tip-sample forces interactions, degrading the image quality. This kind of irregular motion must be avoided by the control system. In this work, the tip-sample interaction is modelled considering the Lennard-Jones potentials and the two-term Galerkin aproximation. Additionally, the State Dependent Ricatti Equation and Time-Delayed Feedback Control techniques are used in order to force the Tapping-Mode Atomic Force Microscope system motion to a periodic orbit, preventing the microcantilever chaotic motion