The Experts below are selected from a list of 228 Experts worldwide ranked by ideXlab platform
Hilmi Demiray - One of the best experts on this subject based on the ideXlab platform.
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A note on the amplitude modulation of symmetric regularized long-wave equation with quartic nonlinearity
Journal of Engineering Mathematics, 2012Co-Authors: Hilmi DemirayAbstract:We study the amplitude modulation of a symmetric regularized long-wave equation with quartic nonlinearity through the use of the reductive perturbation method by introducing a new set of slow variables. The nonlinear Schrodinger (NLS) equation with seventh Order nonlinearity is obtained as the evolution equation for the Lowest Order Term in the perturbation expansion. It is also shown that the NLS equation with seventh Order nonlinearity assumes an envelope type of solitary wave solution.
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Higher Order approximations in reductive perturbation method: strongly dispersive waves
Communications in Nonlinear Science and Numerical Simulation, 2005Co-Authors: Hilmi DemirayAbstract:Abstract Contribution of higher Order Terms in the perturbation expansion for the strongly dispersive ion-plasma waves is examined through the use of modified reductive perturbation method developed early by us. It is shown that the Lowest Order Term in the expansion is governed by the nonlinear Schrodinger equation while the second-Order Term is governed by the linear Schrodinger equation. For the small wave number region a set of solution is presented for the evolution equations.
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Contribution of Higher Order Terms in Nonlinear Ion-Acoustic Waves: Strongly Dispersive Case
Journal of the Physical Society of Japan, 2002Co-Authors: Hilmi DemirayAbstract:Contribution of higher Order Terms in the perturbation expansion for the strongly dispersive ion-plasma waves is examined through the use of modified reductive perturbation method developed by us [J. Phys. Soc. Jpn. 68 (1999) 1833]. In the analysis it is shown that the Lowest Order Term in the expansion is governed by the nonlinear Schrodinger equation while the second Order Term is governed by the linear Schrodinger equation. For the small wave number region a set of solution is presented for the evolution equations.
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Localized travelling waves in a prestressed thick elastic tube
International Journal of Non-Linear Mechanics, 2001Co-Authors: Hilmi DemirayAbstract:Abstract In the present work, by using the exact non-linear equations of an incompressible inviscid fluid contained in a prestressed thick elastic tube, the propagation of localized travelling wave solution in such a medium is investigated. Employing the hyperbolic tangent method and considering the long-wave limit, we showed that the Lowest-Order Term in the perturbation expansion gives a solitary wave equivalent to the localized travelling wave solution of the Korteweg–de Vries equation. The progressive wave type of solution is also sought for the second-Order Terms in the perturbation expansion. The correction Terms in the speed of propagation are obtained as part of the solution of perturbation equations.
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Dressed solitary waves in fluid-filled elastic tubes
International Journal of Non-Linear Mechanics, 1999Co-Authors: Hilmi DemirayAbstract:Abstract In the present work, by using the exact non-linear equations of an incompressible inviscid fluid contained in a prestressed thin elastic tube, the possibility of propagation of a localized travelling wave solution is investigated. Employing the hyperbolic tangent method and considering the long-wave limit, we showed that the Lowest-Order Term in the perturbation expansion is governed by the Korteweg–de Vries equation. The solitary wave type of solution is also given for the second-Order Terms in the expansion. The correction Terms in the speed of propagation are also obtained as a part of the solution of perturbation equations. The applicability of the present model to flow problems in arteries is also discussed.
Erick Pruchnicki - One of the best experts on this subject based on the ideXlab platform.
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NonLinearly Elastic Membrane Model For Heterogeneous Shells by Using a New Double Scale Variational Formulation: A Formal Asymptotic Approach
Journal of Elasticity, 2006Co-Authors: Erick PruchnickiAbstract:This paper is concerned with the asymptotic analysis of shells with periodically rapidly varying heterogeneities. The asymptotic analysis is performed when both the periods of changes of the material properties and the thickness of the shell are of the same Orders of magnitude. We consider a shell made of Saint Venant–Kirchhoff type materials for which we justify a new two-scale variational formulation. We assume that both the data and the displacement field admit a formal asymptotic expansion with a negative Order of the leading Term. We prove that the Lowest Order Term of the displacement field must be of Order zero. When the space of nonlinear inextensional displacement is reduced to $\left\{ 0\right\} $ , this displacement field is a solution of a two-dimensional membrane model which is obtained by solving two coupled problems. The first, posed on the middle surface of the shell is two-dimensional and global and the second, posed on the periodicity cell, is three-dimensional and local.
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Nonlinearly elastic membrane model for heterogeneous plates: a formal asymptotic approach by using a new double scale variational formulation
International Journal of Engineering Science, 2002Co-Authors: Erick PruchnickiAbstract:This paper is concerned with the asymptotic analysis of plates with periodically rapidly varying heterogeneities. The asymptotic analysis is performed when both the material properties and the thickness of the plate are of the same Orders of magnitude. We consider a plate made of Saint Venant–Kirchhoff type materials then we justify a new two-scale variational formulation. We assume that both the data and the displacement field admit a formal asymptotic expansion with a negative Order of the leading Term. We then prove that the Lowest Order Term of the displacement field must be of Order zero. Finally, we consider the particular case of a laminated plate clamped along its lateral boundary and we show that this Term satisfies a two-dimensional nonlinear membrane model.
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Nonlinearly elastic membrane model for heterogeneous shells : a formal asymptotic approach by using a niew double scare variationnal formulation
International Journal of Engineering Science, 2002Co-Authors: Erick PruchnickiAbstract:This paper is concerned with the asymptotic analysis of plates with periodically rapidly varying heterogeneities. The asymptotic analysis is performed when both the material properties and the thickness of the plate are of the same Orders of magnitude. We consider a plate made of Saint Venant–Kirchhoff type materials then we justify a new two-scale variational formulation. We assume that both the data and the displacement field admit a formal asymptotic expansion with a negative Order of the leading Term. We then prove that the Lowest Order Term of the displacement field must be of Order zero. Finally, we consider the particular case of a laminated plate clamped along its lateral boundary and we show that this Term satisfies a two-dimensional nonlinear membrane model.
Amirhosein Mojavezi - One of the best experts on this subject based on the ideXlab platform.
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Kink properties in Lorentz-violating scalar field theory.
arXiv: High Energy Physics - Theory, 2021Co-Authors: Reza Moazzemi, Mohammad Mehdi Ettefaghi, Amirhosein MojaveziAbstract:We consider topological defects for the $\lambda\phi^4$ theory in (1+1) dimensions with a Lorentz-violating background. It has been shown, by M. Barreto et al. (2006) \cite{barreto2006defect}, one cannot have original effects in (the leading Order of) single scalar field model. Here, we introduce a new Lorentz-violating Term, next to leading Order which cannot be absorbed by any redefinition of the scalar field or coordinates. Our Term is the Lowest Order Term which leads to concrete effects on the kink properties. We calculate the corrections to the kink shape and the corresponding mass. Quantization of the kink is performed and the revised modes are obtained. We find the bound and continuum states are affected due to this Lorentz symmetry violation.
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Kink properties in Lorentz-violating scalar field theory
Nuclear Physics B, 2021Co-Authors: Reza Moazzemi, Mohammad Mehdi Ettefaghi, Amirhosein MojaveziAbstract:Abstract We consider topological defects for the λ ϕ 4 theory in (1+1) dimensions with a Lorentz-violating background. It has been shown, by M. Barreto et al. (2006) [34] , one cannot have original effects in (the leading Order of) single scalar field model. Here, we introduce a new Lorentz-violating Term, next to leading Order which cannot be absorbed by any redefinition of the scalar field or coordinates. Our Term is the Lowest Order Term which leads to concrete effects on the kink properties. We calculate the corrections to the kink shape and the corresponding mass. Quantization of the kink is performed and the revised modes are obtained. We find the bound and continuum states are affected due to this Lorentz symmetry violation.
M.tacettin Sarioglu - One of the best experts on this subject based on the ideXlab platform.
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Dressed solitary waves in a fluid filled thin elastic tube
International Journal of Engineering Science, 1999Co-Authors: M.tacettin SariogluAbstract:In the present work, by employing the approximate nonlinear equations of an incompressible inviscid fluid contained in a prestressed thin elastic tube, the propagation of a localized travelling wave solution is examined. Employing the hyperbolic tangent method and considering the longwave limit, we showed that the Lowest Order Term in the perturbation expansion is governed by the Korteweg-de Vries equation of which the solution may be expressed as a solitary wave. It is also shown that the second Order Terms in the expansion can be described by a solitary wave. The correction Terms in the speed of propagation are also obtained as a part of the solution of the perturbation expansion. The applicability of the present model to flow problems in arteries is also discussed.
Reza Moazzemi - One of the best experts on this subject based on the ideXlab platform.
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Kink properties in Lorentz-violating scalar field theory.
arXiv: High Energy Physics - Theory, 2021Co-Authors: Reza Moazzemi, Mohammad Mehdi Ettefaghi, Amirhosein MojaveziAbstract:We consider topological defects for the $\lambda\phi^4$ theory in (1+1) dimensions with a Lorentz-violating background. It has been shown, by M. Barreto et al. (2006) \cite{barreto2006defect}, one cannot have original effects in (the leading Order of) single scalar field model. Here, we introduce a new Lorentz-violating Term, next to leading Order which cannot be absorbed by any redefinition of the scalar field or coordinates. Our Term is the Lowest Order Term which leads to concrete effects on the kink properties. We calculate the corrections to the kink shape and the corresponding mass. Quantization of the kink is performed and the revised modes are obtained. We find the bound and continuum states are affected due to this Lorentz symmetry violation.
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Kink properties in Lorentz-violating scalar field theory
Nuclear Physics B, 2021Co-Authors: Reza Moazzemi, Mohammad Mehdi Ettefaghi, Amirhosein MojaveziAbstract:Abstract We consider topological defects for the λ ϕ 4 theory in (1+1) dimensions with a Lorentz-violating background. It has been shown, by M. Barreto et al. (2006) [34] , one cannot have original effects in (the leading Order of) single scalar field model. Here, we introduce a new Lorentz-violating Term, next to leading Order which cannot be absorbed by any redefinition of the scalar field or coordinates. Our Term is the Lowest Order Term which leads to concrete effects on the kink properties. We calculate the corrections to the kink shape and the corresponding mass. Quantization of the kink is performed and the revised modes are obtained. We find the bound and continuum states are affected due to this Lorentz symmetry violation.
