Nonlinear Dynamic Systems
Mostrando 1-12 de 87 artigos, teses e dissertações.
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1. ON AN INTEGRATED DYNAMIC CHARACTERIZATION OF VISCOELASTIC MATERIALS BY FRACTIONAL DERIVATIVE AND GHM MODELS
Abstract The passive vibration control of mechanical systems under unwanted vibrations can be accomplished in a very effective way by using devices incorporating viscoelastic materials. The design of such devices requires a broad knowledge of the dynamic properties of the employed viscoelastic material, usually supplied by adequate mathematical models. Among
Lat. Am. j. solids struct.. Publicado em: 14/03/2019
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2. On the Nonlinear Transient Analysis of Planar Steel Frames with Semi-Rigid Connections: From Fundamentals to Algorithms and Numerical Studies
Abstract This paper presents the fundamentals for prediction of a more realistic behavior of planar steel frames with semi-rigid connections under dynamic loading. The majority of the research in this area concentrates on the nonlinear static analysis of frames with semi-rigid connections. Indeed, few studies have contributed to the nonlinear dynamic and vi
Lat. Am. j. solids struct.. Publicado em: 03/05/2018
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3. Time Domain Modeling and Simulation of Nonlinear Slender Viscoelastic Beams Associating Cosserat Theory and a Fractional Derivative Model
Abstract A broad class of engineering systems can be satisfactory modeled under the assumptions of small deformations and linear material properties. However, many mechanical systems used in modern applications, like structural elements typical of aerospace and petroleum industries, have been characterized by increased slenderness and high static and dynamic
Lat. Am. j. solids struct.. Publicado em: 2017-01
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4. A Simple FEM Formulation Applied to Nonlinear Problems of Impact with Thermomechanical Coupling
Abstract The thermal effects of problems involving deformable structures are essential to describe the behavior of materials in feasible terms. Verifying the transformation of mechanical energy into heat it is possible to predict the modifications of mechanical properties of materials due to its temperature changes. The current paper presents the numerical d
Lat. Am. j. solids struct.. Publicado em: 2017
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5. Tip Deflection Determination of a Barrel for the Effect of an Accelerating Projectile Before Firing Using Finite Element and Artificial Neural Network Combined Algorithm
Abstract For realistic applications, design and control engineers have limited modelling options in dealing with some vibration problems that hold many nonlinearity such as non-uniform geometry, variable velocity loadings, indefinite damping cases, etc. For these reasons numerous time consuming experimental studies at high costs must be done for determining
Lat. Am. j. solids struct.. Publicado em: 2016-10
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6. On the Validation of a Numerical Model for the Analysis of Soil-Structure Interaction Problems
Abstract Modeling and simulation of mechanical response of structures, relies on the use of computational models. Therefore, verification and validation procedures are the primary means of assessing accuracy, confidence and credibility in modeling. This paper is concerned with the validation of a three dimensional numerical model based on the finite element
Lat. Am. j. solids struct.. Publicado em: 2016-08
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7. An Extended Kalman Filter-Based Technique for On-Line Identification of Unmanned Aerial System Parameters
ABSTRACT: The present article deals with the identification, at the same time, of aircraft stability and control parameters taking into account dynamic damping derivatives. Such derivatives, due to the rate of change of the angle of attack, are usually neglected. So the damping characteristics of aircraft dynamics are attributed only on pitch rate derivative
J. Aerosp. Technol. Manag.. Publicado em: 2015-09
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8. A time-domain finite element model reduction method for viscoelastic linear and nonlinear systems
AbstractMany authors have shown that the effective design of viscoelastic systems can be conveniently carried out by using modern mathematical models to represent the frequency- and temperature-dependent behavior of viscoelastic materials. However, in the quest for design procedures of real-word engineering structures, the large number of exact evaluations o
Lat. Am. j. solids struct.. Publicado em: 2015-06
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9. Vibrations of beams with a variable cross-section fixed on rotational rigid disks
The work is focused on the problem of vibrating beams with a variable cross-section fixed on a rotational rigid disk. The beam is loaded by a transversal time varying force orthogonal to an axis of the beam and simultaneously parallel to the disk's plane. There are many ways of usage of the technical moveable systems composed of elements with the variable cr
Lat. Am. j. solids struct.. Publicado em: 2013-01
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10. On dynamic self-organization: examples from magmatic and other geochemical systems
Standard Liesegang banding is the display of parallel bands of precipitate formed periodically when co-precipitate ions interdiffuse in a gel medium. The most striking resemblance with Liesegang patterns in Nature lies in the diverse scenery of banded textural features commonly observed in some geological materials, such as geodes, agates, malachites, as wel
Lat. Am. j. solids struct.. Publicado em: 2013-01
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11. Programação dinâmica aplicada à otimização individualizada e desacoplada das usinas hidrelétricas de sistemas hidrotérmicos / Dynamic programming applied to individual and decoupled optimization of hydroelectric power plants on hydrothermal systems
O planejamento da operação energética de sistemas hidrotérmicos de potência tem como objetivo determinar a participação de usinas termoelétricas e hidrelétricas de forma a garantir o suprimento desta energia ao menor custo operacional possível, dentro de restrições técnicas. Alguns fatores tornam a solução desse problema bastante complexa dest
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 19/04/2012
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12. Uma arquitetura híbrida aplicada em problemas de aprendizagem por reforço / A hybrid architecture to address reinforcement learning problems
With the evergrowing use of cognitive systems in various applications, it has been created a high expectation and a large demand for machines more and more autonomous, intelligent and creative in real world problem solving. In several cases, the challenges ask for high adaptive and learning capability. This work deals with the concepts of reinforcement learn
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 07/02/2012