Results 11 to 20 of about 499,713 (313)
VibrationA new frequency–amplitude formula by improving an ancient Chinese mathematics method results in a modification of He’s formula. The Chinese mathematics method that expresses via a fixed-point Newton form is proven to be equivalent to the original ...
Chein-Shan Liu +2 more
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Design of 2D TeraHertz band-gap photonic waveguides using an accelerated integral equation technique [PDF]
, 2009 This paper describes the application of the buffered block forward backward (BBFB) method to the problem of modeling 2D terahertz (THz) photonic band gap waveguides at the frequency of 3 THz.
D. Bogusevschi +7 more
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Industria: Jurnal Teknologi dan Manajemen Agroindustri, 2022 Moringa leaves are a source of high antioxidants. This study aims to find an equation model for the extraction conditions of Moringa leaves with Pulsed Electric Field (PEF) pretreatment.
Sukardi Sukardi +2 more
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Fast computation of the nonlocal boundary condition in finite difference parabolic equation radiowave propagation simulations [PDF]
, 2008 Finite difference parabolic equation method (FD-PEM) codes using a nonlocal boundary condition to model radiowave propagation over electrically large domains, require the computation of time consuming spatial convolution integrals. For the first time, we
Mias, Christos
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High Frequency limit of the Helmholtz Equations
Revista Matemática Iberoamericana, 2002 We derive the high frequency limit of the Helmholtz equations in terms of quadratic observables. We prove that it can be written as a stationary Liouville equation with source terms. Our method is based on the Wigner Transform, which is a classical tool for evolution dispersive equations.
Benamou, Jean-David +3 more
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On Propagation of Rayleigh Type Surface Wave in Five Different Theories of Thermoelasticity
International Journal of Applied Mechanics and Engineering, 2019 The governing equations for a homogeneous and isotropic thermoelastic medium are formulated in the context of coupled thermoelasticity, Lord and Shulman theory of generalized thermoelasticity with one relaxation time, Green and Lindsay theory of ...
B. Singh, S. Verma
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Solution to a Damped Duffing Equation Using He’s Frequency Approach
The Scientific World Journal, 2022 In this paper, we generalize He’s frequency approach for solving the damped Duffing equation by introducing a time varying amplitude. We also solve this equation by means of the homotopy method and the Lindstedt–Poincaré method.
Alvaro H. S. Salas +2 more
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Fractional Differential Equation-Based Instantaneous Frequency Estimation for Signal Reconstruction
Fractal and Fractional, 2021 In this paper, we propose a fractional differential equation (FDE)-based approach for the estimation of instantaneous frequencies for windowed signals as a part of signal reconstruction.
Bilgi Görkem Yazgaç, Mürvet Kırcı
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Free linear vibrations of a viscoelastic spherical shell with filler [PDF]
Известия высших учебных заведений: Прикладная нелинейная динамикаPurpose. Thin multilayered shells are widely used in aviation, shipbuilding, and mechanical engineering. Recently, interest in the dynamic analysis of shell structures under various load effects has increased.
Mirsaidov, Mirziyod Mirsaidovich +3 more
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The Differential Equation of the Distribution of Gene Frequencies [PDF]
Proceedings of the National Academy of Sciences, 1945 Not ...
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