Results 21 to 30 of about 559,362 (165)
Exact Solution and Exotic Fluid in Cosmology
Entropy, 2012 We investigate cosmological consequences of nonlinear sigma model coupled with a cosmological fluid which satisfies the continuity equation. The target space action is of the de Sitter type and is composed of four scalar fields.
Phillial Oh, Taeyoon Moon, Seyen Kouwn
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THE MATHEMATICAL MODEL OF DOME COVERING INDUSTRIAL FACILITY
Architecture and Engineering, 2017 A statically determinate flat truss models the industrial facility's arch. To derive dependence of structural deflection on the number of panels in a span, the Maxwell–Mohr equation, computer mathematics system Maple and the induction method are applied.
Mikhail Kirsanov, Sergei Astahov
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MathematicsThis paper solves a nonhomogeneous version of the pantograph equation. The nonhomogeneous term is taken as a polynomial of degree n with arbitrary coefficients.
Mona D. Aljoufi
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Exact charged traversable wormhole solution
Physics Letters BAn exact analytical solution for the charged traversable wormhole solution has been found by solving minimally coupled Einstein-Maxwell-Scalar (EMS) field equations.
Bobur Turimov +3 more
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An inductive method of calculation of the deflection of the truss regular type
Architecture and Engineering, 2016 In this paper, the author proposes a regular option of statically determinate flat truss with a lattice of Shukhov's type working under beam scheme. By induction, using Maple computer algebra system, the exact formula for the mid-span deflection under ...
Mikhail Kirsanov
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Analytical and Numerical Investigation for the Inhomogeneous Pantograph Equation
AxiomsThis paper investigates the inhomogeneous version of the pantograph equation. The current model includes the exponential function as the inhomogeneous part of the pantograph equation.
Faten Aldosari, Abdelhalim Ebaid
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General solutions of the Laplace equation
Partial Differential Equations in Applied Mathematics, 2022 With the purpose of concisely and effectively obtaining the general or exact solutions of partial differential equations (PDEs), we put forward some universal Z1transformations in present paper.
Hong Lai Zhu
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Exact solutions of a charged wormhole [PDF]
Physical Review D, 2001 In this paper, the backreaction to the traversable Lorentzian wormhole spacetime by the scalar field or electric charge is considered to find the exact solutions. The charges play the role of the additional matter to the static wormhole which is already constructed by the exotic matter.
Kim, Sung-Won, Lee, Hyunjoo
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Exact solution for the nonlinear pendulum
Revista Brasileira de Ensino de FísicaThis paper deals with the nonlinear oscillation of a simple pendulum and presents not only the exact formula for the period but also the exact expression of the angular displacement as a function of the time, the amplitude of oscillations and the angular
A. Beléndez +4 more
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Exact solution of the Susceptible–Infectious–Recovered–Deceased (SIRD) epidemic model
Electronic Journal of Qualitative Theory of Differential Equations, 2022 Exact solution of the Susceptible-Infectious-Recovered-Deceased (SIRD) epidemic model is established, and various properties of solution are derived directly from the exact solution.
Norio Yoshida
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