Fourier Series
Mostrando 13-24 de 156 artigos, teses e dissertações.
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13. An Analytical Time Domain Solution for the Forced Vibration Analysis of Thick-Walled Cylinders
Abstract In this paper, we propose a time domain analytical solution for the forced vibration analysis of thick-walled hollow cylinders in presence of polar orthotropy. In this regard, solution of the governing equation is decomposed into two parts. The role of the first one is to satisfy boundary conditions utilizing the method of separation of variables be
Lat. Am. j. solids struct.. Publicado em: 2017-09
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14. The Long-Range Memory and the Fractal Dimension: a Case Study for Alcântara
ABSTRACT: This study aimed to analyze the time series behavior of the Southern Oscillation Index through techniques using Fast Fourier Transform, computing the autocorrelation function, and the calculation of the Hurst coefficient. The methodology of Hurst Exponent calculation uses different lags, which are computed in the time series of Southern Oscillation
J. Aerosp. Technol. Manag.. Publicado em: 24/08/2017
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15. Fourier analysis of nonlinear pendulum oscillations
Since the times of Galileo, it is well-known that a simple pendulum oscillates harmonically for any sufficiently small angular amplitude. Beyond this regime and in absence of dissipative forces, the pendulum period increases with amplitude and then it becomes a nonlinear system. Here in this work, we make use of Fourier series to investigate the transition f
Rev. Bras. Ensino Fís.. Publicado em: 20/07/2017
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16. Oscilador harmônico: Uma análise via séries de Fourier
Mostramos que o método das séries de Fourier para resolver a equação do oscilador harmônico simples foi mal utilizado no artigo “Estados ligados em um potencial delta duplo via transformadas seno e cosseno de Fourier” publicado na Revista Brasileira de Ensino de Física v. 36, n. 2.
Rev. Bras. Ensino Fís.. Publicado em: 13/03/2017
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17. Development of an Analytical Method to Predict the Behaviour of the Magnetic Field in PM Linear Motors with Halbach Array
Abstract This paper describes the application of the method of separation of variables and the use of Fourier series for solving the Laplace's and Poisson's equations on the study and analysis of the magnetic field produced in a linear motor with Halbach array. Equations for predicting the 2D magnetic flux density distribution produced in the air gap were de
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-03
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18. Free and Forced Vibration Analysis of Stepped Circular Cylindrical Shells with Several Intermediate Supports Using an Extended Wave Method; a Generalized Approach
Abstract A combination of vectorial form of wave method (VWM) with Fourier expansion series is proposed as a new vehicle for free and forced vibration analysis of stepped cylindrical shells with multiple intermediate flexible supports. The flexible supports can include springs with arbitrary properties in the possible directions. Based on Flügge thin shell
Lat. Am. j. solids struct.. Publicado em: 2016-11
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19. Synthesis, Optical Characterization, and Size Distribution Determination by Curve Resolution Methods of Water-Soluble CdSe Quantum Dots
In this work a colloidal approach to synthesize water-soluble CdSe quantum dots (QDs) bearing a surface ligand, such as thioglycolic acid (TGA), 3-mercaptopropionic acid (MPA), glutathione (GSH), or thioglycerol (TGH) was applied. The synthesized material was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), UV-visibl
Mat. Res.. Publicado em: 24/10/2016
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20. Synthesis, Characterization and in vitro Antioxidant Activity of New Chiral N-boc Organotellurium Compounds, (CH3)3OC(O)NHCH(R)C(O)NHCH2-CH2Te-C6H4-4-OCH3, Containing Carbamate and Peptide Groups
Synthesis, characterization and antioxidant activity of a new series of chiral N-boc oraganotellurium compounds, (CH3)3OC(O)NHCH(R)C(O)NHCH2CH2Te-C6H4-4-OCH3, containing carbamate and peptide groups have been reported in this paper. These chiral peptides were synthesized in good to excellent yields, via acid-amine coupling reaction of N-boc L-amino acids wit
J. Braz. Chem. Soc.. Publicado em: 2016-06
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21. Respiratory syncytial virus seasonality in Brazil: implications for the immunisation policy for at-risk populations
Respiratory syncytial virus (RSV) infection is the leading cause of hospitalisation for respiratory diseases among children under 5 years old. The aim of this study was to analyse RSV seasonality in the five distinct regions of Brazil using time series analysis (wavelet and Fourier series) of the following indicators: monthly positivity of the immunofluoresc
Mem. Inst. Oswaldo Cruz. Publicado em: 29/03/2016
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22. Closed-form elasticity solution for three-dimensional deformation of functionally graded micro/nano plates on elastic foundation
This paper addresses the static deformation of simply supported rectangular micro/nano plates made of functionally graded (FG) materials based on the three-dimensional nonlocal elasticity theory of Eringen. The plates are assumed to be simply supported and rested on a Winkler-Pasternak elastic foundation. Elasticity modulus is assumed to obey an exponential
Lat. Am. j. solids struct.. Publicado em: 2015-08
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23. Transverse Motions of Rectangular Plates Resting on Elastic Foundation and Under Concentrated Masses Moving at Varying Velocities
AbstractThis study concerns the dynamic characteristics of a prestressed isotropic, rectangular plate continuously supported by an elastic foundation and carrying accelerating mass M. Closed form solutions of the governing fourth order partial differential equations with variable and singular coefficients are presented. For the two-dimensional plate problem,
Lat. Am. j. solids struct.. Publicado em: 2015-07
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24. Harmonic Analysis of Multipath Index Time Series in GPS Stations
A identificação de variações cíclicas e sazonais é muito importante em séries temporais. Neste artigo, objetiva-se identificar a presença de variações cíclicas e sazonais nos índices do efeito do multicaminho em estações GPS (Global Positioning System) de monitoramento contínuo. Devido ao modelo usado na obtenção de tais series, não deveria
TEMA (São Carlos). Publicado em: 2015-04