Vibrations
Mostrando 25-36 de 372 artigos, teses e dissertações.
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25. Dynamic analysis of gun barrel vibrations due to effect of an unbalanced projectile considering 2-D transverse displacements of barrel tip using a 3-D element technique
Abstract In this paper, dynamic analysis of two different weapon systems (35 mm Anti-Aircraft Barrel (AAB) and 120 mm Grooved Tank Barrel (GTB)) under the effect of statically unbalanced projectile has been performed with a new 12 DOF 3-D element technique using Finite Element Method (FEM). The muzzle deviations, which negatively affect the barrel shooting a
Lat. Am. j. solids struct.. Publicado em: 06/08/2018
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26. Releasing systems for aerospace industry based upon Shape Memory Alloys: characterization of materials for actuators
ABSTRACT Releasing and deployment maneuvers carried out during space satellites launching are usually performed by utilizing pyrotechnics loads. However, it is considered convenient to replace this technique by others not requiring explosives (Non Explosive Actuators-NEA). This is mainly due to the necessity of reducing high-shock and vibrations induced leve
Matéria (Rio J.). Publicado em: 19/07/2018
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27. Structural, optical and electrical properties of Ni-doped Co3O4 prepared via Sol-Gel technique
In this article, Nickel doped Cobalt oxide thin films and powders have been prepared on glass substrates using sol gel based dip coating process in order to investigate their optical, structural and electrical properties. The Ni concentration was changed from 0 to 9 wt(%).The synthesized samples were characterised by Ultraviolete visible analysis, X-ray diff
Mat. Res.. Publicado em: 07/02/2018
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28. Analysis of Geometrically Nonlinear Vibrations of Functionally Graded Shallow Shells of a Complex Shape
Abstract Geometrically nonlinear vibrations of functionally graded shallow shells of complex planform are studied. The paper deals with a power-law distribution of the volume fraction of ceramics and metal through the thickness. The analysis is performed with the use of the R-functions theory and variational Ritz method. Moreover, the Bubnov-Galerkin and the
Lat. Am. j. solids struct.. Publicado em: 2017-09
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29. Nonlinear Vibration Analysis of Euler-Bernoulli Beams by Using Continuous Galerkin-Petrov Time-Discretization Method
Abstract In this paper, we present a new numerical method for nonlinear vibrational analysis of Euler-Bernoulli beams. Our approach is based on the continuous Galerkin-Petrov time discretization method. The Euler-Bernoulli beam equation which governs its vibrations is transformed into set of ordinary differential equations and the presented method is employe
Lat. Am. j. solids struct.. Publicado em: 2017-09
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30. MODIFICAÇÃO QUÍMICA DA PECTINA DO MELÃO CAIPIRA (Cucumis melo VAR. ACIDULUS)
Melon is one of the most widely consumed fruits in the world. In Brazil, 60% of the production is for domestic consumption, with these fruits deemed to be of lower commercial value. For the first time, pectin has been extracted from this species of melon. So the extraction of this polysaccharide can be used as an alternative to increase the value of the frui
Quím. Nova. Publicado em: 2017-06
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31. Experimental Evaluation of Low-Pass Shock Isolation Performance of Elastomers Using Frequency-Based Kolsky Bar Analyses
Abstract Elastomeric materials are used as shock isolation materials in a variety of environments to dampen vibrations and/or absorb energy from external impact for minimizing energy transfer between two objects or bodies. Some applications require the shock isolation materials to behave as a low-pass mechanical filter to mitigate the shock/impact at high fr
Lat. Am. j. solids struct.. Publicado em: 2017-03
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32. Campbell Diagrams of a Spinning Composite Shaft with Curvilinear Fibers
Abstract This paper presents the vibratory behavior of a spinning composite shaft with curvilinear fibers on rigid bearings in the case of free vibrations. A p-version of finite element is used to define the model. A theoretical study allows the establishment of the kinetic energy and the strain energy of the shaft, necessary to the result of the equations o
Lat. Am. j. solids struct.. Publicado em: 2017-03
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33. Vibration Analysis of a Cylindrical Sandwich Panel with Flexible Core Using an Improved Higher-Order Theory
Abstract This paper deals with free vibration analysis of thick cylindrical composite sandwich panels with simply supported boundary conditions based on a new improved higher-order sandwich panel theory. The formulation used the third-order polynomial description for the displacement fields of thick composite face sheets and for the displacement fields in th
Lat. Am. j. solids struct.. Publicado em: 2017-03
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34. A Modified FEM for Transverse and Lateral Vibration Analysis of Thin Beams Under a Mass Moving with a Variable Acceleration
Abstract In this paper, a new modified finite element method that can be used in the analysis of transverse and lateral vibrations of the thin beams under a point mass moving with a variable acceleration and constant jerk is presented. Jerk is the change in acceleration over time. In this method, the classical finite element of the beam is modified by the in
Lat. Am. j. solids struct.. Publicado em: 2017-03
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35. APPLICATION OF OPTICAL METHOD IN MEASURING MECHANICAL VIBRATIONS IN A CANTILEVER BEAM
ABSTRACT The pertinent literature discloses a family of optical profile measuring techniques highlighting the moiré methods. The Moiré technique is based on the interference of two superimposed optical grids which produce fringe patterns which can be processed to analyze the DYNAMIC MEASUREMENT IN MATERIALS mechanical behavior. The goal of this research is
Eng. Agríc.. Publicado em: 2017-02
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36. Parametric Modal Dynamic Analysis of Steel-Concrete Composite Beams with Deformable Shear Connection
Abstract Composite structural elements of steel-concrete began to be used only in 1960 after the development of methods and constructive dispositions that ensured the functionality of these two materials together. In order to verify the importance of the participation of the axial mode in the frequency spectrum of the free vibration problem in composite beam
Lat. Am. j. solids struct.. Publicado em: 2017-02