Controle robusto de sistemas não lineares e chaveado de sistemas lineares usando realimentação derivativa

Pós-graduação em Engenharia Elétrica - FEIS

Dinâmica não linear e projeto de controle em sistemas de transporte vertical: comportamentos periódicos e caóticos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estratos

This paper presents a diagram that was produced in the dissertation “Vibrations: Art/Education in Practice and Discourse within Mental Health” which was developed within the Arts Graduate Program at Unesp. From the archaeological perspective proposed by Foucault, it was sought to excavate strata or layers of knowledge built around the concepts of madness, subjectivity and art, in order to emphasize the historical transformations that these conceptions have undergone over time, through words and images.

Estudo comparativo de filmes de corantes fenotiazínicos na superfície de eletrodo de carbono vítreo e adsorvidos em titânio fosfatado e suas aplicações eletroanalíticas

Pós-graduação em Ciência dos Materiais - FEIS

Effects of railway track vibration induced by passing trains on an energy harvesting device

Pós-graduação em Engenharia Mecânica - FEIS

A influência da música nas atividades físicas e sua impressão no corpo e nos estados de ânimo

Numerous studies in physical education and music's area have been conducted to improve the quality of life and health of people, all of them under physiological, psychological and social fields. Thus, when properly analyzed, both Areas are connected, because the movement itself, main subject of physical education, has a close proximity to the rhythm, an essential element of music. That's why it is important to discover the benefits of this relationship, because, in many of its practices, physical education makes use of music, for example, in aerobic gymnastic and dance classes. As a consequence, this study aims to investigate, through literature, the influence of music in physical activities and its imprinting in the states of mind and body of practitioners, as well as clarify the criteria for choice of songs that are used in such practice. This research occurred under literary explore, done through theoretical analysis of the thematic. At first place, a contextualization of the auditory system and its relationship with the music and the perception of sound were made, then the main theme was explored. The music, even before generate and influence motor and psychic movements in the human body, is already moving in space, because it is formed through vibrations of molecules. It is decoded first as a movement from the ears, and then decoded as sound, when in the brain. It is important to worry about sounds at high intensities and also with those which are outside the hearing thresholds within physical activities involving music, because they may be harmful to health and also to states of mind. As far as music and movement is concerned, they are closely linked, and the human being has an instinctive sense of rhythm that can be seen when listening to music, because the motor cortex is also activated. Therefore, it is important to work the sound and body movement together, because in practice they are inseparable and they contribute greatly to...

Contribution of electrical parameters on the dynamical behaviour of a nonlinear electromagnetic damper

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

Active modal damping control of a smart truss structure using a self-organizing fuzzy controller

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

Rietveld refinement and optical properties of SrWO4:Eu3+ powders prepared by the non-hydrolytic sol-gel method

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

On energy harvesting form time-limited excitations: simulations and case study

Linear resonant harvesters have been the most common type of generators used to scavenge energy from mechanical vibrations. When subject to harmonic excitation, good performance is achieved once the device is tuned so that its natural frequency coincides with the excitation frequency. In such a situation, the average power harvested in a cycle is proportional to the cube of the excitation frequency and inversely proportional to the suspension damping, which is sought to be very low. However, a very low damping involves a relatively long transient in the system response, where the classical formulation adopted for steady-state regimes do not hold. This paper presents an investigation into the design of a linear resonant harvester to scavenge energy from time-limited harmonic excitations involving a transient response, which could be more likely in some practical situations. An application is presented considering train-induced vibrations.

Influence of structural nonlinearities in stall-induced aeroelastic response of pitching airfoils

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

Amorphous ZrF4-a molecular dynamics study

Using an effective two-body interaction potential, a molecular dynamics study of the structural properties of amorphous ZrF4 phase is presented. The effective pair potential includes steric repulsion, Coulomb interaction due to charge transfer, and charge-dipole interaction due to the large electronic polarizability of anions. The results for structural correlations, such as pair distribution functions, coordination numbers, and bond angle distributions are presented. Excellent agreement is obtained by comparing experimental X-ray diffraction and the simulated static X-ray structure factor. © 1993.

Raman and infrared investigations of glass and glass-ceramics with composition 2Na2O·1CaO·3SiO2

Precursor glass and glass-ceramics with molar composition 2Na2O·1CaO·3SiO2 are studied by infrared, conventional, and microprobe Raman techniques. The Gaussian deconvoluted Raman spectrum of the glass presents bands at 625 and 660 cm-1, attributed to bending vibrations of Si-O-Si bonds, and at 860, 920, 975, and 1030 cm-1, attributed to symmetric stretching vibrations of SiO4 tetrahedra with 4, 3, 2, and 1 nonbridging oxygens, respectively. The Raman microprobe spectrum of a highly crystallized sample presents two narrow and intense bands at about 590 and 980 cm-1, associated with vibrations of SiO4 tetrahedra with two nonbridging oxygens, in agreement with the predicted chain-like structure of crystalline metasilicates. Scanning electron microscopy shows that the crystals distributed in partially crystallized samples have a spherical shape, built up by radially oriented needle-like single crystals. The Raman microprobe spectra of these spherulites show that they still contain residual amorphous material. A comparison of Raman and infrared spectra of amorphous and highly crystallized samples is presented.

Oxygen Interstitial Dynamics in Bi(2)Sr(2)CaCu(2)O(8+delta) Oxides Measured by Mechanical Spectroscopy

Many researchers became interested in the discovery of Bi(2)Sr(2)CaCu(2)O(8+delta) oxides with critical temperature of around 80 K. It is known that the critical temperature is related to the CuO2 planes of the material. For this reason, the study of the interstitial oxygen in these oxides is of great relevance. The samples were prepared by means of conventional solid state reactions, through the stoichiometric mixture of precursory powders. After the sinterization, the samples were submitted to measurements of density, electrical resistivity, x-ray diffraction, scanning electron microscopy and energy dispersion spectroscopy, with the objective of performing their characterization. The measurements of mechanical spectroscopy were performed by a torsion pendulum. The results show three relaxation processes in the temperature range of 200 and 700 K, with activation energy of approximately 0.9 eV, which has been attributed to the dynamics of the interstitial oxygen present in the material.

Análise dinâmica em vigas compostas com amortecimento utilizando o método dos elementos espectrais e elementos finitos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)