On the Limit Cycles for a Class of Perturbed Fifth-Order Autonomous Differential Equations

We study the limit cycles of the fifth-order differential equation x ⋅ ⋅ ⋅ ⋅ ⋅ − e x ⃜ − d x ⃛ − c x ¨ − b x ˙ − a x = ε F x , x ˙ , x ¨ , x ⋯ , x ⃜ with a = λ μ δ , b = − λ μ + λ δ + μ δ , c = λ + μ + δ + λ μ δ , d = − 1 + λ μ + λ δ + μ δ , e = λ + μ + δ , where ε is a small enough real parameter, λ , μ , and δ are real parameters, and F ∈ C 2 is a nonlinear function. Using the averaging theory of first order, we provide sufficient conditions for the existence of limit cycles of this equation.

Solution of Fractional Autonomous Ordinary Differential Equations

Autonomous differential equations of fractional order and non-singular kernel are solved. While solutions can be obtained through numerical, graphical, or analytical solutions, we seek an implicit analytical solution.

Ring of flows of one-dimensional differential equations

In this paper, we construct a ring of flows, where we can decompose one-dimensional autonomous differential equations into smaller parts, then solve each part and finally put everything together to obtain the exact solution of these equations.

STABILITY AND BOUNDEDNESS BEHAVIOUR OF SOLUTIONS OF A CERTAIN SECOND ORDER NON-AUTONOMOUS DIFFERENTIAL EQUATIONS

In this paper, we give sufficient conditions for the stability and ultimate boundedness of solutions to a certain second order non-autonomous differential equations with damped and forced functions. Our results improve and extend some of the stability and boundedness results in the literature which themselves are extensions of some results cited therein. We give example to illustrate the result obtained.

On the Integrable Deformations of the Maximally Superintegrable Systems

In this paper, we present the integrable deformations method for a maximally superintegrable system. We alter the constants of motion, and using these new functions, we construct a new system which is an integrable deformation of the initial system. In this manner, new maximally superintegrable systems are obtained. We also consider the particular case of Hamiltonian mechanical systems. In addition, we use this method to construct some deformations of an arbitrary system of first-order autonomous differential equations.

Averaging theory for fractional differential equations

The theory of averaging is a classical component of applied mathematics and has been applied to solve some engineering problems, such as in the filed of control engineering. In this paper, we develop a theory of averaging on both finite and infinite time intervals for fractional non-autonomous differential equations. The closeness of the solutions of fractional no-autonomous differential equations and the averaged equations has been proved. The main results of the paper are applied to the switched capacitor voltage inverter modeling problem which is described by the fractional differential equations.

GENERALIZED POISSON INTEGRAL AND ITS APPLIED ASPECTS

Mathematical methods based on statistics have been used in sociology for a long time. The functioning of socio-economic and socio-politic systems is a complex process, which is caused by a number of various factors. Thus, the construction of models of socio-economic and socio-politic processes requires solving problems of both the decomposition of structures and processes, and their integration into a single system model, taking into account the changing conditions of the external environment. Mathematical modeling of such problems can be carried out by methods of network analysis or game theory, which allows finding optimal strategies for the behavior of competitive parties. Asymptotic formulations have a central role in game theory, since, due to the complex strategic nature, explicit solutions can be found only in very rare cases. A large number of models created to study complex social processes that occur in society are dynamical systems, or non-autonomous differential equations, or difference equations with a large number of parameters in any cases. In this situation, it is important to choose an appropriate tool for studying the behavior of such systems. In this paper, generalized Poisson delta operators are considered as approximating aggregates, since periodic processes, which are subdivided into harmonic and polyharmonic, provide the internal integrity of complex systems and their dynamic functioning. Questions of the asymptotic behavior of the exact upper bounds for approximations by generalized Poisson delta operators on classes of periodic functions that satisfy the Lipschitz condition are also studied. The received formulas provide a solution to the Kolmogorov-Nikol’ski problem for generalized Poisson delta operators and Lipschitz classes. The proof is based on the use of formulas that give integral representations of the deviations of linear methods generated by linear processes of summation of Fourier series on sets of periodic functions in the uniform metric obtained in the works of L.I. Bausov. The results can be an effective tool for modeling the processes of social dynamics.