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Wyszukujesz frazę "Nonlinear Equations" wg kryterium: Temat


Tytuł:
Nonlinear equations of acoustics - numerical solutions and their visualization
Autorzy:
Wójcik, J.
Lewin, P. A.
Nowicki, A.
Filipczyński, L.
Kujawska, T.
Radulescu, E.
Powiązania:
https://bibliotekanauki.pl/articles/331971.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
acoustics
nonlinear equations
wave equation
Opis:
The novel effective numeric solver of the nonlinear scalar wave equation describing the acoustic wave propagation in the attenuating media was derived. The solver was developed for the PC environment. The standard computation data include al! stationary and dynamic characteristics of the radiated ultrasonic pressure field, especially its 4D (space/time) visualization. The results obtained with the solver can be used as the supporting tools (tool) in designing and developments of the multielement linear and phase array transducers applied in ultrasonography.
Źródło:
Hydroacoustics; 2003, 6; 137-142
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A New Approach for Solving Intuitionistic Dual Fuzzy Nonlinear Fractional Transportation Problem
Autorzy:
Anju, A.
Anukokila, P.
Powiązania:
https://bibliotekanauki.pl/articles/1068615.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Dual
Intuitionistic Fuzzy
Newton Raphson Method
Nonlinear Equations
Opis:
In this paper a new approach is explained for solving intuitionistic dual fuzzy fractional nonlinear equations. Here we have suggested a numerical method for solving a dual fuzzy nonlinear fractional equations instead of standard analytical techniques which are not suitable everywhere. Initially we wrote a dual fuzzy non-linear fractional equations in parametric form and then solve it by iterative method. An illustrative example is given to show the efficiency of our approach.
Źródło:
World Scientific News; 2019, 132; 220-232
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reduction and continuation theorems for Brouwer degree and applications to nonlinear difference equations
Autorzy:
Mawhin, J.
Powiązania:
https://bibliotekanauki.pl/articles/255344.pdf
Data publikacji:
2008
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
Brouwer degree
nonlinear difference equations
Opis:
The aim of this note is to describe the continuation theorem of [39,40] directly in the context of Brouwer degree, providing in this way a simple frame for multiple applications to nonlinear difference equations, and to show how the corresponding reduction property can be seen as an extension of the well-known reduction formula of Leray and Schauder [24], which is fundamental for their construction of Leray-Schauder's degree in normed vector spaces.
Źródło:
Opuscula Mathematica; 2008, 28, 4; 541-560
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On reconstructing unknown characteristics of a nonlinear system of differential equations
Autorzy:
Kuklin, A.
Maksimov, V.
Nikulina, N.
Powiązania:
https://bibliotekanauki.pl/articles/229625.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nonlinear differential equations
dynamical reconstruction
Opis:
Problems of dynamical reconstruction of unknown characteristics for nonlinear equations described the process of diffusion of innovations through results of observations of phase states are considered. Solving algorithms, which are stable with respect to informational noises and computational errors, are designed. The algorithms are based on the principle of auxiliary models with adaptive controls.
Źródło:
Archives of Control Sciences; 2015, 25, 2; 163-176
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A dynamical inverse problem for a parabolic equation
Autorzy:
Maksimov, V.
Powiązania:
https://bibliotekanauki.pl/articles/255796.pdf
Data publikacji:
2006
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
nonlinear parabolic equations
inverse problem
Opis:
A problem of dynamical reconstruction of unknown distributed or boundary disturbances acting upon nonlinear parabolic equations is discussed. A regularized algorithm which allows us to reconstruct disturbances synchro with the process under consideration is designed. This algorithm is stable with respect to informational noises and computational errors.
Źródło:
Opuscula Mathematica; 2006, 26, 2; 327-342
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nonlocal elliptic problems
Autorzy:
Krzywicki, Andrzej
Nadzieja, Tadeusz
Powiązania:
https://bibliotekanauki.pl/articles/1207643.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
nonlinear nonlocal elliptic equations
Opis:
Some conditions for the existence and uniqueness of solutions of the nonlocal elliptic problem $-Δφ = M f(φ)/((∫_{Ω} f(φ))^p)$, $φ|_{\partial Ω}=0$ are given.
Źródło:
Banach Center Publications; 2000, 52, 1; 147-152
0137-6934
Pojawia się w:
Banach Center Publications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An existence and approximation theorem for solutions of degenerate nonlinear elliptic equations
Autorzy:
Cavalheiro, Albo Carlos
Powiązania:
https://bibliotekanauki.pl/articles/747200.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
Degenerate nonlinear elliptic equations
weighted Sobolev spaces
Opis:
The main result establishes that a weak solution of degenerate nonlinear  elliptic equations can be approximated by a sequence of solutions for non-degenerate nonlinear elliptic equations.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica; 2018, 72, 1
0365-1029
2083-7402
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence and uniqueness of solutions for a class of degenerate nonlinear elliptic equations
Autorzy:
Cavalheiro, Albo Carlos
Powiązania:
https://bibliotekanauki.pl/articles/747202.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
Degenerate nonlinear elliptic equations
weighted Sobolev spaces
Opis:
In this work we are interested in the existence and uniqueness of solutions for the Navier problem associated to the degenerate nonlinear elliptic equations \begin{align} {\Delta}(v(x)\, {\vert{\Delta}u\vert}^{p-2}{\Delta}u) &-\sum_{j=1}^n D_j{\bigl[}{\omega}_1(x) \mathcal{A}_j(x, u, {\nabla}u){\bigr]}+ b(x,u,{\nabla}u)\, {\omega}_2(x)\\ & = f_0(x) - \sum_{j=1}^nD_jf_j(x), \ \ {\rm in } \ \ {\Omega} \end{align} in the setting of the weighted Sobolev spaces.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica; 2016, 70, 2
0365-1029
2083-7402
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska, sectio A – Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence and uniqueness of the solutions of some degenerate nonlinear elliptic equations
Autorzy:
Cavalheiro, A. C
Powiązania:
https://bibliotekanauki.pl/articles/255079.pdf
Data publikacji:
2014
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
degenerate nonlinear elliptic equations
weighted Sobolev spaces
Opis:
In this paper we are interested in the existence of solutions for the Dirichlet problem associated with degenerate nonlinear elliptic equations [formula] in the setting of the weighted Sobolev spaces [formula].
Źródło:
Opuscula Mathematica; 2014, 34, 1; 15-28
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Asymptotic properties of the solution of an equation of nonstationary filtration type
Autorzy:
Wyskup, Michał
Powiązania:
https://bibliotekanauki.pl/articles/748523.pdf
Data publikacji:
1978
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Asymptotic behavior of solutions,Nonlinear parabolic equations
Opis:
.
The review of the paper is available at MR0518665.
Źródło:
Mathematica Applicanda; 1978, 6, 13
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mixed nonlinear functional equations and approximation of their solutions. The theory of J. Descloux and J. Rappaz. II. Interior approximation of a branch
Autorzy:
Moszyński, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/747423.pdf
Data publikacji:
1985
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Equations involving nonlinear operators
Abstract bifurcation theory
Equations with nonlinear operators
Opis:
.
In part II the author investigates the inner approximate representation of solutions of the equation F(x)=0 in the neighbourhood of regular and critical points.
Źródło:
Mathematica Applicanda; 1985, 12, 24
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelowanie i symulacja cewki nieliniowej ze stratami w żelazie
Modeling and Simulations of a Non-Linear Coil
Autorzy:
Kolańska-Płuska, J.
Grochowicz, B.
Powiązania:
https://bibliotekanauki.pl/articles/160164.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Elektrotechniki
Tematy:
Metoda RADAU IIA
cewka nieliniowa
równania różniczkowe nieliniowe sztywne
Runge-Kutta methods
nonlinear coil
differential equations
nonlinear equations
Opis:
Praca dotyczy badania dynamiki obwodu z cewką nieliniową z uwzględnieniem strat w żelazie. W pracy został przedstawiony model cewki oraz opis za pomocą zmiennych stanu. Przedstawiono również program do badania dynamiki cewki opracowany w środowisku C#, w którym do rozwiązania układu równań różniczkowych nieliniowych modelujących cewkę nieliniową ze stratami w żelazie zastosowano metodę niejawną RADAU IIA różnych rzędów.
Solving rigid differential equations systems should be performed with the application of implicit or semi-explicit methods. As proven in the example given in this paper – the implicit RADAU IIA methods can be successfully applied for the purpose of solving the rigid non-linear systems. The high-order methods up to 11 cause that the application performs relatively large integration steps in pursuit of the steady state that is comparable with the explicit methods. Furthermore, the number of iterations and computation time for a sample non-linear equations formulated for a coil with iron losses is comparable to other methods such as, e.g., multistep Gear method. Also a sample test has proved that the implicit Runge-Kutta methods can be competitive for the purpose of research regarding electrical systems described with the rigid differential equations compared to the multistep Gear method.
Źródło:
Prace Instytutu Elektrotechniki; 2016, 272; 217-226
0032-6216
Pojawia się w:
Prace Instytutu Elektrotechniki
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A finite element method for extended KdV equations
Autorzy:
Karczewska, A.
Rozmej, P.
Szczeciński, M.
Boguniewicz, B.
Powiązania:
https://bibliotekanauki.pl/articles/330630.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
shallow water wave problem
nonlinear equations
second order KdV equations
finite element method
Petrov–Galerkin method
Opis:
The finite element method (FEM) is applied to obtain numerical solutions to a recently derived nonlinear equation for the shallow water wave problem. A weak formulation and the Petrov–Galerkin method are used. It is shown that the FEM gives a reasonable description of the wave dynamics of soliton waves governed by extended KdV equations. Some new results for several cases of bottom shapes are presented. The numerical scheme presented here is suitable for taking into account stochastic effects, which will be discussed in a subsequent paper.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2016, 26, 3; 555-567
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On theorems for weak solutions of nonlinear differential equations with and without delay in Banach spaces
Autorzy:
Gomaa, Adel Mahmoud
Powiązania:
https://bibliotekanauki.pl/articles/745302.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Nonlinear differential equations
weak solutions
measures of noncompactness
delay
Opis:
In the present work we give an existence theorem for bounded weak solution of the differential equation \[ \dot{x}(t) = A(t)x(t) + f (t, x(t)),\quad t \geq 0 \] where \(\{A(t) : t \in I\mathbb{R}^+ \}\) is a family of linear operators from a Banach space \(E\) into itself, \(B_r = \{x \in E : \|x\| \leq r\}\) and \(f \colon \mathbb{R}^+ \times B_r \to E\) is weakly-weakly continuous. Furthermore, we give existence theorem for the differential equation with delay \[ \dot{x}(t) = \hat{A}(t) x(t) + f^d (t, θ_t x)\quad \text{if}\ t \in [0, T], \] where \(T, d \gt 0\), \(C_{B_r} ([-d, 0])\) is the Banach space of continuous functions from \([-d, 0]\) into \(B_r\), \(f_d\colon [0, T] \times C_{B_r} ([-d, 0]) \to E\) weakly-weakly continuous function, \(\hat{A}(t)\colon [0,T] \to L(E)\) is strongly measurable and Bochner integrable operator on \([0,T]\) and \(θ_t x(s) = x(t + s)\) for all \(s \in [-d, 0]\).
Źródło:
Commentationes Mathematicae; 2007, 47, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mixed nonlinear functional equations and approximation of their solutions. The theory of J. Descloux and J. Rappaz. I. Regular and critical points. Bifurcation
Autorzy:
Moszyński, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/747615.pdf
Data publikacji:
1985
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Methods for solving equations involving nonlinear operator
Abstract bifurcation theory
Equations with nonlinear operators
Opis:
.
The contents of part I lie in the compilation of papers by Descloux and Rappaz ["On numerical approximation of solution branches of nonlinear equations'', École Polytech. Lausanne, Lausanne, 1981; per bibl.; RAIRO Anal. Numér. 16 (1982), no. 4, 319–349; MR0684829]. In Banach spaces the author investigates the implicit nonlinear operator equation F(x)=0 with a sufficiently smooth operator F. He formulates the notions of regular and critical points of an operator and studies the behaviour of the solutions of the equation in the neighbourhood of such points. The theoretical considerations are based on a version of the implicit function theorem.
Źródło:
Mathematica Applicanda; 1985, 12, 24
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bifurcation theorems of Rabinowitz type for certain differential operators of the fourth order
Autorzy:
Przybycin, Jolanta
Powiązania:
https://bibliotekanauki.pl/articles/1312084.pdf
Data publikacji:
1992
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
nonlinear partial differential equations
bifurcation in partial differential equations
Opis:
This paper was inspired by the works of P. H. Rabinowitz. We study nonlinear eigenvalue problems for some fourth order elliptic partial differential equations with nonlinear perturbation of Rabinowitz type. We show the existence of an unbounded continuum of nontrivial positive solutions bifurcating from (μ₁,0), where μ₁ is the first eigenvalue of the linearization about 0 of the considered problem. We also prove the related theorem for bifurcation from infinity. The results obtained are similar to those proved by Rabinowitz for second order elliptic partial differential equations ([5]-[7]). The methods used are based, in principle, on the results of [1], [5], [6].
Źródło:
Annales Polonici Mathematici; 1992, 57, 1; 21-28
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence, uniqueness and estimates of classical solutions to some evolutionary system
Autorzy:
Sapa, L.
Powiązania:
https://bibliotekanauki.pl/articles/255005.pdf
Data publikacji:
2015
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
hyperbolic wave equation
telegraph equation
system of nonlinear equations
existence
uniqueness and estimates of solutions
Hölder space
Opis:
The theorem of the local existence, uniqueness and estimates of solutions in Hölder spaces for some nonlinear differential evolutionary system with initial conditions is formulated and proved. This system is composed of one partial hyperbolic second-order equation and an ordinary subsystem with a parameter. In the proof of the theorem we use the Banach fixed-point theorem, the Arzeli-Ascola lemma and the integral form of the differential problem.
Źródło:
Opuscula Mathematica; 2015, 35, 6; 935-956
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Balance errors in numerical solutions of shallow water equations
Autorzy:
Gąsiorowski, D.
Powiązania:
https://bibliotekanauki.pl/articles/1933150.pdf
Data publikacji:
2007
Wydawca:
Politechnika Gdańska
Tematy:
shallow water equations
nonlinear advection equations
numerical errors
conservation laws
mass and momentum balance
Opis:
An analysis of the conservative properties of shallow water equations is presented, focused on the consistency of their numerical solution with the conservation laws of mass and momentum. Two different conservative forms are considered, solved by an implicit box scheme. Theoretical analysis supported with numerical experiments is carried out for a rectangular channel and arbitrarily assumed flow conditions. The improper conservative form of the dynamic equation is shown not to guarantee a correct solution with respect to the conservation of momentum. Consequently, momentum balance errors occur in the numerical solution. These errors occur when artificial diffusion is simultaneously generated by a numerical algorithm.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2007, 11, 4; 329-340
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Difference problems generated by infinite systems of nonlinear parabolic functional differential equations with the Robin conditions
Autorzy:
Czernous, W.
Jaruszewska-Walczak, D.
Powiązania:
https://bibliotekanauki.pl/articles/255694.pdf
Data publikacji:
2014
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
nonlinear parabolic equations
functional differential equations
infinite systems
Volterra type operators
nonlinear estimates of Perron type
truncation methods
Opis:
We consider the classical solutions of mixed problems for infinite, countable systems of parabolic functional differential equations. Difference methods of two types are constructed and convergence theorems are proved. In the first type, we approximate the exact solutions by solutions of infinite difference systems. Methods of second type are truncation of the infinite difference system, so that the resulting difference problem is finite and practically solvable. The proof of stability is based on a comparison technique with nonlinear estimates of the Perron type for the given functions. The comparison system is infinite. Parabolic problems with deviated variables and integro-differential problems can be obtained from the general model by specifying the given operators.
Źródło:
Opuscula Mathematica; 2014, 34, 2; 311-326
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On optimal and quasi-optimal controls in coefficients for multi-dimensional thermistor problem with mixed Dirichlet-Neumann boundary conditions
Autorzy:
Kogut, Peter I.
Powiązania:
https://bibliotekanauki.pl/articles/970117.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
nonlinear elliptic equations
control in coefficients
p(x)-Laplacian
approximation approach
thermistor problem
Opis:
In this paper we deal with an optimal control problem in coefficients for the system of two coupled elliptic equations, also known as the thermistor problem, which provides a simultaneous description of the electric field u = u(x) and temperature θ(x). The coefficients of the operator div (B(x)∇θ(x)) are used as the controls in L∞(Ω). The optimal control problem is to minimize the discrepancy between a given distribution θd ∈ Lr(Ω) and the temperature of thermistor θ ∈ W1,γ 0 (Ω) by choosing an appropriate anisotropic heat conductivity matrix B. Basing on the perturbation theory of extremal problems and the concept of fictitious controls, we propose an “approximation approach” and discuss the existence of the so-called quasi-optimal and optimal solutions to the given problem.
Źródło:
Control and Cybernetics; 2019, 48, 1; 31-68
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Series Solution of Nonlinear Ordinary Differential Equations Using Single Laplace Transform Method in Mathematical Physics
Autorzy:
Mbagwu, JP. C.
Madububa, B. I.
Nwamba, J. I.
Powiązania:
https://bibliotekanauki.pl/articles/1193352.pdf
Data publikacji:
2021
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Adomian polynomials
Single Laplace transform method
nonlinear ordinary differential equations
Opis:
In this paper, a novel technique is created to enable the extension of the single Laplace transform method (SLTM) to solve nonlinear ordinary differential equations (ODEs) is presented. The main parts of the recommended technique are the Adomian polynomials. By developing several theorems, which include the Laplace transformation of nonlinear expressions, the Adomian polynomials are made possible. Several famous nonlinear equations including the Blasius equation, the Poisson Boltzmann equation, and numerous extra problems relating nonlinearities of many types such as exponential and sinusoidal are resolved for description. As it was revealed in the specified equations, and problems, our technique is conceptually and computationally simple. Some nonlinear examples are taken from the literature for checking the validation and convergence of the proposed technique. The suggested method is methodical, precise, then restricted to integration.
Źródło:
World Scientific News; 2021, 154; 152-174
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exponential decay of solutions to a class of fourth-order nonlinear hyperbolic equations modeling the oscillations of suspension bridges
Autorzy:
Liu, Yang
Yang, Chao
Powiązania:
https://bibliotekanauki.pl/articles/2048892.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
fourth-order nonlinear hyperbolic equations
weak solutions
exponential decay
family of potential wells
Opis:
This paper is concerned with a class of fourth-order nonlinear hyperbolic equations subject to free boundary conditions that can be used to describe the nonlinear dynamics of suspension bridges.
Źródło:
Opuscula Mathematica; 2022, 42, 2; 239-255
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nonlinear dynamic analysis of viscoelastic membranes described with fractional differential models
Analiza nieliniowej dynamiki lepko-sprężystych powłok opisanych modelem o pochodnej ułamkowej
Autorzy:
Katsikadelis, J. T.
Powiązania:
https://bibliotekanauki.pl/articles/280344.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
viscoelastic membranes
nonlinear vibrations
nonlinear fractional differential equations
analog equation method
boundary elements
Opis:
The dynamic response of an initially flat viscoelastic membrane is investigated. The viscoelastic model is described with fractional order derivatives. The membrane is subjected to surface transverse and inplane dynamic loads. The governing equations are three coupled second order nonlinear partial FDEs (fractional differential equations) of hyperbolic type in terms of the displacement components. These equations are solved using the BEM for fractional partial differential equations developed recently by Katsikadelis. Without excluding other viscoelastic models, the herein employed material is the Kelvin-Voigt model with a fractional order derivative. Numerical examples are presented which not only demonstrate the efficiency of the solution procedure, but also give a better insight into this complicated but very interesting response of structural viscoelastic membranes. It is worth noting that in case of resonance, phenomena similar to those of the Duffing equation are observed.
W pracy przedstawiono analizę dynamiki płaskiej powłoki lepko-sprężystej po wstępnym ugięciu. Reologiczny model materiału powłoki opisano równaniem o pochodnych ułamkowych. Powłokę poddano płaskiemu, poprzecznemu obciążeniu zewnętrznemu. Zagadnienie dynamiki ujęto układem trzech sprzężonych nieliniowych równań różniczkowych typu hiperbolicznego o pochodnych ułamkowych. Równania rozwiązano metodą elementów brzegowych (BEM) sformułowaną przez autora właśnie dla układów opisanych pochodnymi ułamkowymi. W prezentowanej pracy założono, że powłoka wykonana jest z lepko-sprężystego materiału Kelvina-Voigta o pochodnej ułamkowej, choć samo sformułowanie BEM nie wyklucza możliwości analizy innych modeli reologicznych. Przedstawiono kilka przykładów symulacji numerycznych pokazujących efektywność zastosowanej metody rozwiązywania oraz dających lepszy obraz interesującej, lecz skomplikowanej dynamiki lepko-sprężystych powłok. Warto również podkreślić, że w warunkach rezonansowych odnotowano zjawiska podobne do obserwowanych w układzie Duffinga.
Źródło:
Journal of Theoretical and Applied Mechanics; 2012, 50, 3; 743-753
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence of three solutions for perturbed nonlinear difference equations
Autorzy:
Heidarkhani, S.
Moghadam, M. K.
Powiązania:
https://bibliotekanauki.pl/articles/952774.pdf
Data publikacji:
2014
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
nonlinear difference equations
discrete boundary value problem
three solutions
critical point theory
variational methods
Opis:
Using critical point theory, we study the existence of at least three solutions for perturbed nonlinear difference equations with discrete boundary-value condition depending on two positive parameters.
Źródło:
Opuscula Mathematica; 2014, 34, 4; 747-761
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Periodicity of the Population Size of an Age-Dependent Model With a Dominant Age Class by Means of Impulsive Perturbations
Autorzy:
Covachev, V.
Powiązania:
https://bibliotekanauki.pl/articles/929760.pdf
Data publikacji:
2000
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
dynamika populacji
równanie nieliniowe
population dynamics
age-dependent model
periodic solutions
nonlinear delay equations
Opis:
For an age-dependent model with a dominant age class an w-periodic regime of the population size is sought by means of impulsive perturbations. For both noncritical and critical cases of first order the problem is reduced to operator systems solvable by a convergent simple iteration method.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2000, 10, 1; 147-155
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oscillation of nonlinear neutral delay differential equations of second order
Autorzy:
Kubiaczyk, Ireneusz
Saker, Samir
Powiązania:
https://bibliotekanauki.pl/articles/729556.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
oscillation theorems
second order nonlinear neutral delay differential equations
Opis:
Oscillation criteria, extended Kamenev and Philos-type oscillation theorems for the nonlinear second order neutral delay differential equation with and without the forced term are given. These results extend and improve the well known results of Grammatikopoulos et. al., Graef et. al., Tanaka for the nonlinear neutral case and the recent results of Dzurina and Mihalikova for the neutral linear case. Some examples are considered to illustrate our main results.
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2002, 22, 2; 185-212
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Linearization of the ship equations of motion
Autorzy:
Mielewczyk, A.
Powiązania:
https://bibliotekanauki.pl/articles/245238.pdf
Data publikacji:
2013
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
transport
mechanical engineering
Maritime Engineering
nonlinear differential equations
linearization
resistance of hull
error solutions
Opis:
In real systems are non-linear mathematical description. The exact solution can not be determined, and then look for approximate methods. Important is the type of nonlinearity, solutions and error method approximation. Linearization is an essential part of creating a model of the selected process. Ship resistance is a function of power with exponent two and higher. Model motion of the ship must have a solution in terms of maneuverability speed and speed of the sea. The solution must be well reproduce the actual path of the transition and the transition time of the ship. Nonlinear solution method determines the accuracy of the answers. Has presented the revised approach to solve the nonlinear differential equation of parabolic function. Linearization has been made in the selected range, and not where you want it to work and solve the error estimate. Range of solutions selected by external priorities adopted. Before the solution is estimated response error. The error value determines whether the selected interval will apply. If the problem solution is unacceptable, it will increase the accuracy of the result of the narrow scope of the work. The new scope of work should also be reassessed a solution error. This type of approach correlates with fuzzy logic, where we use the value of the Boolean variable with the function of belonging. The combination of classical methods of solving differential equations of the theory of fuzzy sets can bring new benefits. Such a solution must have the function of the accuracy of the answers. The linearization method meets this requirement.
Źródło:
Journal of KONES; 2013, 20, 2; 269-275
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Mesh-Independence Principle for Quadratic Penalties Applied to Semilinear Elliptic Boundary Control
Autorzy:
Grossman, Christian
Winkler, Max
Powiązania:
https://bibliotekanauki.pl/articles/1373554.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Jagielloński. Wydawnictwo Uniwersytetu Jagiellońskiego
Tematy:
optimal boundary control
mesh-independence principle
penalty methods for control constraints
weakly nonlinear elliptic equations
Opis:
The quadratic loss penalty is a well known technique for optimization and control problems to treat constraints. In the present paper they are applied to handle control bounds in a boundary control problems with semilinear elliptic state equations. Unlike in the case of finite dimensional optimization for infinite dimensional problems the order of convergence could only be roughly estimated, but numerical experiments revealed a clearly better convergence behavior with constants independent of the dimension of the used discretization. The main result in the present paper is the proof of sharp convergence bounds for both, the finite und infinite dimensional problem with a mesh-independence in case of the discretization. Further, to achieve an efficient realization of penalty methods the principle of control reduction is applied, i.e. the control variable is represented by the adjoint state variable by means of some nonlinear function. The resulting optimality system this way depends only on the state and adjoint state. This system is discretized by conforming linear finite elements. Numerical experiments show exactly the theoretically predicted behavior of the studied penalty technique.
Źródło:
Schedae Informaticae; 2012, 21; 9-26
0860-0295
2083-8476
Pojawia się w:
Schedae Informaticae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Blow-up behavior in nonlocal vs local heat equations
Autorzy:
Souplet, Philippe
Powiązania:
https://bibliotekanauki.pl/articles/1207661.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
asymptotic behavior
boundary behavior
nonlinear parabolic equations
blow-up profiles
nonlocal source
finite time blow-up
Opis:
We present some recent results on the blow-up behavior of solutions of heat equations with nonlocal nonlinearities. These results concern blow-up sets, rates and profiles. We then compare them with the corresponding results in the local case, and we show that the two types of problems exhibit "dual" blow-up behaviors.
Źródło:
Banach Center Publications; 2000, 52, 1; 221-226
0137-6934
Pojawia się w:
Banach Center Publications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sustainable Exploitation of Biological Populations
Autorzy:
Grasman, J.
Powiązania:
https://bibliotekanauki.pl/articles/929749.pdf
Data publikacji:
2000
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
rybołówstwo
równanie różnicowe
optimal harvesting
system of nonlinear difference equations
fishery
host-parasitoid system
stabilizing feedback
Opis:
For a system of nonlinear difference equations that models the dynamics of exploited biological populations, a locally optimal periodic solutionis constructed. If this solution is unstable, a stabilizing feedback in the harvesting is introduced. The method is applied to an age-structured population model in fishery as well as to a host-parasitoid system for which the number of hosts and the number of introduced parasitoids shouldbe minimized.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2000, 10, 1; 123-129
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some stability conditions for scalar Volterra difference equations
Autorzy:
Berezansky, L.
Migda, M.
Schmeidel, E.
Powiązania:
https://bibliotekanauki.pl/articles/254995.pdf
Data publikacji:
2016
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
linear and nonlinear Volterra difference equations
boundedness of solutions
exponential and asymptotic stability
Opis:
New explicit stability results are obtained for the following scalar linear difference equation [formula] and for some nonlinear Volterra difference equations.
Źródło:
Opuscula Mathematica; 2016, 36, 4; 459-470
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nonlocal quadratic evolution problems
Autorzy:
Biler, Piotr
Woyczyński, Wojbor
Powiązania:
https://bibliotekanauki.pl/articles/1207633.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
self-similar solutions
fractal anomalous diffusion
asymptotic behavior of solutions
nonlinear nonlocal parabolic equations
Opis:
Nonlinear nonlocal parabolic equations modeling the evolution of density of mutually interacting particles are considered. The inertial type nonlinearity is quadratic and nonlocal while the diffusive term, also nonlocal, is anomalous and fractal, i.e., represented by a fractional power of the Laplacian. Conditions for global in time existence versus finite time blow-up are studied. Self-similar solutions are constructed for certain homogeneous initial data. Monte Carlo approximation schemes by interacting particle systems are also mentioned.
Źródło:
Banach Center Publications; 2000, 52, 1; 11-24
0137-6934
Pojawia się w:
Banach Center Publications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence of solution of the nonlinear Dirichlet problem for differential-functional equations of elliptic type
Autorzy:
Brzychczy, Stanisław
Powiązania:
https://bibliotekanauki.pl/articles/1311834.pdf
Data publikacji:
1993
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
nonlinear differential-functional equations of elliptic type
monotone iterative technique
Chaplygin's method
Dirichlet problem
Opis:
Consider a nonlinear differential-functional equation (1) Au + f(x,u(x),u) = 0 where $Au := ∑_{i,j=1}^m a_{ij}(x) (∂²u)/(∂x_i ∂x_j)$, $x=(x_1,...,x_m) ∈ G ⊂ ℝ^m$, G is a bounded domain with $C^{2+α}$ (0 < α < 1) boundary, the operator A is strongly uniformly elliptic in G and u is a real $L^p(G̅)$ function. For the equation (1) we consider the Dirichlet problem with the boundary condition (2) u(x) = h(x) for x∈ ∂G. We use Chaplygin's method [5] to prove that problem (1), (2) has at least one regular solution in a suitable class of functions. Using the method of upper and lower functions, coupled with the monotone iterative technique, H. Amman [3], D. H. Sattinger [13] (see also O. Diekmann and N. M. Temme [6], G. S. Ladde, V. Lakshmikantham, A. S. Vatsala [8], J. Smoller [15]) and I. P. Mysovskikh [11] obtained similar results for nonlinear differential equations of elliptic type. A special case of (1) is the integro-differential equation $Au + f(x,u(x), ∫_G u(x)dx) = 0$. Interesting results about existence and uniqueness of solutions for this equation were obtained by H. Ugowski [17].
Źródło:
Annales Polonici Mathematici; 1993, 58, 2; 139-146
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Coercive limits for a subclass of monotonne constitutive equations in the theory of inelastic material behaviour of metals
Autorzy:
Chełmiński, Krzysztof
Powiązania:
https://bibliotekanauki.pl/articles/747547.pdf
Data publikacji:
1997
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Time-dependent problems
Other equations from mechanics
Equations involving nonlinear operators
Yield criteria and flow rules
Opis:
.
We prove existence and uniqueness of strong global in tme solution for a subclass of monotone constitutive equations in the theory of inelastic material behaviour of metals without the coercivity assumption for the free energy function. We approximate noncoercive models by a sequence of coercive problems and prove the convergence result.
Źródło:
Mathematica Applicanda; 1997, 26, 40
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cellular Automata and Many-Particle Systems Modeling Aggregation Behavior Among Populations
Autorzy:
Morale, D.
Powiązania:
https://bibliotekanauki.pl/articles/929762.pdf
Data publikacji:
2000
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
równanie różniczkowe stochastyczne
równanie różniczkowo-całkowe
cellular automata
individual-based models
stochastic differential equations
law of large numbers
density dependence
nonlinear integrodifferential equations
Opis:
A cellular automaton model is presented in order to describe mutual interactions among the individuals of a population due to social decisions.The scheme is used for getting qualitative results, comparable to field experiments carried out on a population of ants which present an aggregative behavior. We also present a second description of a biological spatially structured population of N individuals by a system of stochastic differential equations of Ito type. A 'law of large numbers' to a continuum dynamics described by an integro-differential equation is given.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2000, 10, 1; 157-173
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A New Computational Method Based on Laguerre Polynomials for Solving Certain Nonlinear Partial Integro Differential Equations
Autorzy:
Gürbüz, B.
Sezer, M.
Powiązania:
https://bibliotekanauki.pl/articles/1031188.pdf
Data publikacji:
2017-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
nonlinear partial integro-differential equations
Laguerre polynomials
matrix and collocation methods
error estimations
Opis:
In this study, we consider some nonlinear partial integro-differential equations. Most of these equations are used as mathematical models in many problems of physics, biology, chemistry, engineering, and in other areas. Our main purpose is to propose a new numerical method based on the Laguerre and Taylor polynomials, called matrix collocation method, for the numerical solution of the mentioned nonlinear equations under the initial or boundary conditions. To show the effectiveness of this approach, some examples along with error estimations are illustrated by tables and figures.
Źródło:
Acta Physica Polonica A; 2017, 132, 3; 561-563
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Solution of nonlinear stiff differential equations for a three-phase no-load transformer using a Runge–Kutta implicit method
Autorzy:
Baron, Bernard
Kolasińska-Płuska, Joanna
Łukaniszyn, Marian
Spałek, Dariusz
Kraszewski, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/2172805.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
circuit model of a three-phase transformer
Runge-Kutta implicit methods
stiff nonlinear ordinary diferential equations
Opis:
The paper presents an approach to differential equation solutions for the stiff problem. The method of using the classic transformer model to study nonlinear steady states and to determine the current pulses appearing when the transformer is turned on is given. Moreover, the stiffness of nonlinear ordinary differential state equations has to be considered. This paper compares Runge–Kutta implicit methods for the solution of this stiff problem.
Źródło:
Archives of Electrical Engineering; 2022, 71, 4; 1081--1106
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Solving a system of nonlinear equations with the use of optimization methods in problems related to the wheel-rail contact
Autorzy:
Jureczko, M.
Duda, S.
Powiązania:
https://bibliotekanauki.pl/articles/122469.pdf
Data publikacji:
2016
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
wheel-rail contact
system of nonlinear equations
Newton's method
trust region method
Levenberg-Marquardt method
damped Newton’s method
styk koło-szyna
układ równań nieliniowych
metoda Newtona
metoda Levenberg-Marquardt
Opis:
The article presents the methods for defining the geometry of the contact surface between a rigid wheel and a rigid rail. The calculation model that has been developed allowed for any arrangement of the wheel in relation to the rail. This allowed for the creation of a system of nonlinear equations, the solution of which allows one to determine the presumable wheel-rail contact points. The search for the solution of the system of strongly nonlinear equations was conducted using a few optimization methods. This allowed one to study both the selection of the starting point and the convergence of the method.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2016, 15, 2; 53-64
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Boundary integral solution for a class of fourth-order two-point boundary value problems
Autorzy:
Al-Gahtani, H. J.
Powiązania:
https://bibliotekanauki.pl/articles/122949.pdf
Data publikacji:
2016
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
boundary integral method
fourth-order differential equation
nonlinear ordinary differential equations
nieliniowe równania różniczkowe zwyczajne
równanie różniczkowe czwartego rzędu
Opis:
In this paper, a boundary integral method is proposed for the solution of a class of fourth-order two-boundary value problems described by the equation yiv+P(x, y, y, y’’, y’’’) = 0, x ∈ ( 0,L), where P is a polynomial function of its arguments. The differential equation is cast in an integral form and the weighted residual technique is used to generate the corresponding boundary integral equations. The boundary integral equations are then, solved by expressing the dependent variable, y, in terms of a power series. The proposed method is tested through four examples to show the applicability of the method to solve a wide range of fourth-order differential equations including the nonlinear ones.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2016, 15, 3; 5-13
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The homotopy analysis Rangaig transform method for nonlinear partial differential equations
Autorzy:
Ziane, Djelloul
Cherif, Mountassir Hamdi
Powiązania:
https://bibliotekanauki.pl/articles/2175522.pdf
Data publikacji:
2022
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
Rangaig transform method
homotopy analysis method
nonlinear partial differential equations
metoda transformacji Rangaiga
metoda analizy homotopii
nieliniowe równania różniczkowe cząstkowe
Opis:
The idea suggested in this article is to combine the Rangaig transform with the homotopy analysis method in order to facilitate the solution of nonlinear partial differentia equations. This method may be called the homotopy analysis Rangaig transform method (HARTM). The proposed example results showed that HARTM is an effective method for solving nonlinear partial differential equations.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2022, 21, 2; 111--122
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rescaled multilevel least-change almost secant methods
Autorzy:
Grzegorski, S. M.
Powiązania:
https://bibliotekanauki.pl/articles/748509.pdf
Data publikacji:
1991
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Systems of equations
Nonlinear programming
Opis:
.
In this article the theory of local convergence is developed. One of the extensions consists in that the approximations to the Jacobian matrix have the same properties as the same matrix has in the solution. The example shows that this assumption may lead to simpler algorithms. The paper discusses several rescaled multilevel least-change updates for which local g-superlinear convergence is proved. The theory may be applied to a wider class of methods because every secant algorithm may be treated as a rescaled least-change method.
Źródło:
Mathematica Applicanda; 1991, 19, 33
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Variation of parameters method for a three-dimensional problem of condensation film on an inclined rotating disk
Autorzy:
Güngör, Osman
Arslantürk, Cihat
Powiązania:
https://bibliotekanauki.pl/articles/122445.pdf
Data publikacji:
2019
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
condensation
rotating inclined disk
nonlinear ordinary differential equations
variation of parameters method
VPM
kondensacja
nieliniowe równania różniczkowe zwyczajne
metoda zmiany parametrów
Opis:
In this paper, the steady three-dimensional problem of condensation film on an inclined rotating disk is considered. The governing nonlinear partial differential equations are reduced to the nonlinear ordinary differential equations system by a similarity transform. The equation system is solved by the variation of parameters method (VPM) which is rather used to solve nonhomogeneous linear differential equations but can also be used to solve nonlinear differential equations. This method has not previously been used to solve a nonlinear condensation problem. The dimensionless velocity and temperature profiles are shown, and the influence of Prandtl number and rotation ratio on the flow field and the Nusselt number are discussed in detail. In order to assess the accuracy of the solutions obtained by this method, the problem is also solved numerically using the Matlab bvp4c solver. The validity of our solutions is verified by the numerical results.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2019, 18, 1; 15-28
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The existence of monotonic solutions of a class of quadratic integral equations of Volterra type
Autorzy:
Karakurt, Osman
Temizer, Ӧmer Faruk
Powiązania:
https://bibliotekanauki.pl/articles/357726.pdf
Data publikacji:
2019
Wydawca:
Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
Tematy:
nonlinear Volterra integral equations
measure of noncompactness
fixed point theorem
nieliniowe równania całkowe Volterry
miara braku zgodności
twierdzenie o punkcie stałym
Opis:
Using the technique associated with measure of noncompactness we prove the existence of monotonic solutions of a class of quadratic integral equation of Volterra type in the Banach space of real functions defined and continuous on a bounded and closed interval.
Źródło:
Journal of Mathematics and Applications; 2019, 42; 117-133
1733-6775
2300-9926
Pojawia się w:
Journal of Mathematics and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oscillation theorems concerning non-linear differential equations of the second order
Autorzy:
Elabbasy, E.M.
Elzeiny, Sh.R.
Powiązania:
https://bibliotekanauki.pl/articles/255765.pdf
Data publikacji:
2011
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
second order
nonlinear
differential equations
oscillation
Opis:
This paper concerns the oscillation of solutions of the differential eq. [r,(t) ψ(x(t)) ƒ (x(t))] + q(t) φ (g(x(t)), r(t)ψ(x(t))=0 where uφ(u,v) > 0 for all u ≠ 0, xg(x)>0, xf(x)>0 for all x ≠ 0, ψ(x)>0 for all x ∈ R, r(t)>0 for t≥t0>0 and q is of arbitrary sign. Our results complement the results in [A.G. Kartsatos, On oscillation of nonlinear quations of second order, J. Math. Anal. Appl. 24 (1968), 665-668], and improve a number of existing oscillation criteria. Our main results are illustrated with examples.
Źródło:
Opuscula Mathematica; 2011, 31, 3; 373-391
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of the classical implicit function theorem in sensitivity analysis of parametric optimal control
Autorzy:
Malanowski, K.
Powiązania:
https://bibliotekanauki.pl/articles/206654.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
równania różniczkowe nieliniowe
różniczkowalność rozwiązań
sterowanie optymalne parametryczne
differentiability of solutions
implicit function theorem
nonlinear ordinary differential equations
parametric optimal control
state constraints
Opis:
A family {(O[sub h])} of parametric optimal control problems for nonlinear ODEs is considered. The problems are subject to pointwise inequality type state constraints. It is assumed that the reference solution is regular. The original problems (O[sub h]) are substituted by problems [...] subject to equality type constraints with the sets of activity depending on the parameter. Using the classical implicit function theorem, conditions are derived under which stationary points of [...] are Frechet differentiable functions of the parameter. It is shown that, under additional conditions, the stationary points of [...] correspond to the solutions and Lagrange multipliers of (O[sub h]9).
Źródło:
Control and Cybernetics; 1998, 27, 3; 335-352
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nonlinear Interaction of Modes in a Planar Flow of a Gas with Viscous and Thermal Attenuation
Autorzy:
Perelomova, Anna
Powiązania:
https://bibliotekanauki.pl/articles/177137.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
nonlinear wave theory
nonlinear acoustics
coupling dynamic equations
Burgers equation
diffusion equation
Opis:
The nonlinear interaction of wave and non-wave modes in a gas planar flow are considered. Attention is mainly paid to the case when one sound mode is dominant and excites the counter-propagating sound mode and the entropy mode. The modes are determined by links between perturbations of pressure, density, and fluid velocity. This definition follows from the linear conservation equations in the differentia form and thermodynamic equations of state. The leading order system of coupling equations for interacting modes is derived. It consists of diffusion inhomogeneous equations. The main aim of this study is to identify the principle features of the interaction and to establish individual contributions of attenuation (mechanical and thermal attenuation) in the solution to the system.
Źródło:
Archives of Acoustics; 2019, 44, 3; 551-559
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Generalization of Linear Rosenstark Method of Feedback Amplifier Analysis to Nonlinear One
Autorzy:
Borys, A.
Zakrzewski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/226780.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
weakly nonlinear amplifiers
nonlinear Rosenstark model
nonlinear distortion analysis
harmonic distortion
constitutive equations
Volterra series
Opis:
Generalization of Linear Rosenstark Method of Feedback Amplifier Analysis to Nonlinear One This paper deals with an extension of the Rosenstark’s linear model of an amplifier to a nonlinear one for the purpose of performing nonlinear distortion analysis. Contrary to an approach using phasors, our method uses the Volterra series. Relying upon the linear model mentioned above, we define first a set of the so-called amplifier’s constitutive equations in an operator form. Then, we expand operators using the Volterra series truncated to the first three components. This leads to getting two representations in the time domain, called in-network and input-output type descriptions of an amplifier. Afterwards, both of these representations are transferred into the multi-frequency domains. Their usefulness in calculations of any nonlinear distortion measure as, for example, harmonic, intermodulation, and/or cross-modulation distortion is demonstrated. Moreover, we show that they allow a simple calculation of the so-called nonlinear transfer functions in any topology as, for example, of cascade and feedback structures and their combinations occurring in single-, two-, nd three-stage amplifiers. Examples of such calculations are given. Finally in this paper, we comment on usage of such notions as nonlinear signals, intermodulation nonlinearity, and on identification of transfer function poles and zeros lying on the frequency axis with related real-valued frequencies.
Źródło:
International Journal of Electronics and Telecommunications; 2014, 60, 1; 48-60
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On existence and uniqueness of solutions of nonlocal problems for hyperbolic differential-functional equations in two independent variables
Autorzy:
Człapiński, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/1294572.pdf
Data publikacji:
1997
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
differential-functional equations
nonlinear hyperbolic problems
nonlocal conditions
Opis:
We seek for classical solutions to hyperbolic nonlinear partial differential-functional equations of the second order. We give two theorems on existence and uniqueness for problems with nonlocal conditions in bounded and unbounded domains.
Źródło:
Annales Polonici Mathematici; 1997, 67, 3; 205-214
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The interaction of linear boundary value and nonlinear functional conditions
Autorzy:
Fečkan, Michal
Powiązania:
https://bibliotekanauki.pl/articles/1311814.pdf
Data publikacji:
1993
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
differential equations
linear and nonlinear conditions
Fredholm operators
Opis:
The existence of solutions is studied for certain nonlinear differential equations with both linear and nonlinear conditions
Źródło:
Annales Polonici Mathematici; 1993, 58, 3; 299-310
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł

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