Results 1 to 10 of about 143,113 (265)

Periodic solutions for a system of nonlinear neutral functional difference equations with two functional delays [PDF]

Mathematica Moravica, 2015
In this paper, we study the existence and uniqueness of periodic solutions of the system of nonlinear neutral difference equations ∆x (n) = A(n) x (n - t (n)) + ∆Q(n; x (n - g (n))) + G(n; x (n) ; x (n - g (n))).
Mesmouli Billah Mouataz, Ardjouni Abdelouaheb, Djoudi Ahcene   +2 more
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On extension of solutions of a simultaneous system of iterative functional equations [PDF]

Opuscula Mathematica, 2009
Some sufficient conditions which allow to extend every local solution of a simultaneous system of equations in a single variable of the form \[ \varphi(x) = h (x, \varphi[f_1(x)],\ldots,\varphi[f_m(x)]),\] \[\varphi(x) = H (x, \varphi[F_1(x)],\ldots ...
Janusz Matkowski
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Periodic solutions for an impulsive system of integro-differential equations with maxima [PDF]

Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2022
A periodical boundary value problem for a first-order system of ordinary integro-differential equations with impulsive effects and maxima is investigated.
Tursun K. Yuldashev
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Nonpotentiality of a diffusion system and the construction of a semi-bounded functional [PDF]

Қарағанды университетінің хабаршысы. Математика сериясы, 2021
The wide prevalence and the systematic variational principles are used in mathematics and applications due to a series of remarkable consequences among which the possibility to establish the existence of the solutions of the initial equations ...
V.M. Savchin, L.T. Huyen
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Attractors of 2D Navier–Stokes system of equations in a locally periodic porous medium [PDF]

Қарағанды университетінің хабаршысы. Математика сериясы, 2022
This article deals with two-dimensional Navier–Stokes system of equations with rapidly oscillating term in the equations and boundary conditions. Studying the problem in a perforated domain, the authors set homogeneous Dirichlet condition on the
K.A. Bekmaganbetov, G.A. Chechkin, A.M. Toleubay   +2 more
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A system of biadditive functional equations in Banach algebras

Applied Mathematics in Science and Engineering, 2023
In this paper, we obtain the general solution and the Hyers-Ulam stability of the system of biadditive functional equations $$\begin{align*} \begin{cases} 2f(x+y,z+w)-g(x,z)-g(x,w)=g(y,z)+g(y,w)\\ g(x+y,z+w)-2f(x-y,z-w)=4f(x,w)+4f(y,z) \end{cases} \end ...
Yamin Sayyari, Mehdi Dehghanian, Choonkil Park   +2 more
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A system of additive functional equations in complex Banach algebras

Demonstratio Mathematica, 2023
In this article, we solve the system of additive functional equations: 2f(x+y)−g(x)=g(y),g(x+y)−2f(y−x)=4f(x)\left\{\phantom{\rule[-1.25em]{}{0ex}}\begin{array}{l}2f\left(x+y)-g\left(x)=g(y),\\ g\left(x+y)-2f(y-x)=4f\left(x)\end{array}\right.
Paokanta Siriluk, Dehghanian Mehdi, Park Choonkil, Sayyari Yamin   +3 more
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Reduction of Linear Functional Systems using Fuhrmann's Equivalence

Sultan Qaboos University Journal for Science, 2016
Functional systems arise in the treatment of systems of partial differential equations, delay-differential equations, multidimensional equations, etc. The problem of reducing a linear functional system to a system containing fewer equations and unknowns ...
Mohamed S. Boudellioua
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Method of functional parametrization for solving a semi-periodic initial problem for fourth-order partial differential equations

Қарағанды университетінің хабаршысы. Математика сериясы, 2020
A semi-periodic initial boundary-value problem for a fourth-order system of partial differential equations is considered. Using the method of functional parametrization, an additional parameter is carried out and the studied problem is reduced to the ...
A.T. Assanova, Zh.S. Tokmurzin
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Stability results for the functional differential equations associated to water hammer in hydraulics

Electronic Journal of Qualitative Theory of Differential Equations, 2022
There is considered a system of two sets of partial differential equations describing the water hammer in a hydroelectric power plant containing the dynamics of the tunnel, turbine penstock, surge tank and hydraulic turbine.
Vladimir Rasvan
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