Results 11 to 20 of about 487,972 (266)
Fractal and Fractional, 2022 The propagation of optical soliton profiles in plasma physics and atomic structures is represented by the (1+1)− dimensional Schrödinger dynamical equation, which is the subject of this study.
Muhammad Abu Bakar +4 more
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A Review of Matrix SIR Arino Epidemic Models
Mathematics, 2021 Many of the models used nowadays in mathematical epidemiology, in particular in COVID-19 research, belong to a certain subclass of compartmental models whose classes may be divided into three “(x,y,z)” groups, which we will call respectively “susceptible/
Florin Avram +2 more
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Kyushu Journal of Mathematics, 1995 The Bohr-Mollerup theorem asserts that the gamma function \(\Gamma (a)\) is the only function defined for \(a > 0\) such that (i) \(\Gamma (a) > 0\), (ii) \(\Gamma (1) = 1\), (iii) \(a \Gamma (a) = \Gamma (a + 1)\), and (iv) \(\Gamma (a)\) is logarithmically convex. The authors use this to prove the well-known result (1) \(\zeta' (0,a) = \log \Gamma (a)
Choi, Junesang, Nam, Young Man
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First Integrals of Differential Operators from SL(2,ℝ) Symmetries
Mathematics, 2020 The construction of first integrals for SL(2,R)-invariant nth-order ordinary differential equations is a non-trivial problem due to the nonsolvability of the underlying symmetry algebra sl(2,R).
Paola Morando +2 more
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Crossing Periodic Orbits via First Integrals [PDF]
International Journal of Bifurcation and Chaos, 2020 We characterize the families of periodic orbits of two discontinuous piecewise differential systems in [Formula: see text] separated by a plane using their first integrals. One of these discontinuous piecewise differential systems is formed by linear differential systems, and the other by nonlinear differential systems.
Llibre, Jaume +2 more
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Darboux and rational first integrals for a family of cubic three dimensional systems
Zanco Journal of Pure and Applied Sciences, 2021 In this paper, we investigate the first integrals of the following system exam.PNG exam1.PNG This kind of system is a particular case of the jerk cubic three dimensional polynomial differential systems.
Sarbast Hussein Mikaeel, Azad I. Amen
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The solution of some persistent $p : -q$ resonant center problems
Electronic Journal of Qualitative Theory of Differential Equations, 2018 The notion of $p:-q$ resonant center was introduced recently and studied by several authors. In this paper we generalize the notion of a persistent center to a persistent $p:-q $ resonant center and find conditions for existence of a persistent $p:-q ...
Maja Zulj +2 more
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Journal of Mathematical Analysis and Applications, 2005 The authors consider properties of first return integrals of real functions defined on the unit interval. First-return integrals are shown to be continuous but not absolutely continuous.
Csörnyei, Marianna +3 more
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Darboux and Analytic First Integrals of Kingni–Jafari System with Only One Stable Equilibrium Point.
Zanco Journal of Pure and Applied Sciences, 2020 In this paper, we illustrate by an evidence that the Kingni–Jafari differential system where and are real parameters has no Darboux and rational first integrals for any value of Furthermore, we show that this system has no global first integrals ...
Shno F. Muhammed +2 more
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Science Journal of University of Zakho, 2017 The main purpose of this paper is to study the existence of polynomial inverse integrating factor and first integral, and non-existence of limit cycles for all systems. Furthermore, we consider some applications.
Ahmed M. Hussien
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