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Wyszukujesz frazę "value problem" wg kryterium: Temat


Tytuł:
The Use of Cubic Spline Functions to Two-point Boundary Value Problems
Autorzy:
Hobot, G.
Powiązania:
https://bibliotekanauki.pl/articles/747453.pdf
Data publikacji:
1992
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Boundary value problem
Opis:
W pracy podany jest algorytm, który konstruuje funkcję sklejaną stopnia 3-go będącą rozwiązaniem przybliżonym 2-punktowego, liniowego zadania brzegowego dla równań różniczkowych zwyczajnych. Korzysta on z faktu, że współczynniki poszukiwanej funkcji sklejanej zależą liniowo od parametru t, który jest równy wartości tej funkcji sklejanej w węźle xo. Algorytm wymaga O(N) działań arytmetycznych, gdzie A jest liczbą podpodziałów rozważanego przedziału. Oprócz algorytmu przedstawione są wyniki obliczeń, które uzyskano testując algorytm na kilku przykładach
In this paper we consider an algorithm for cubic spline function approximation of the solution of two-point boundary value problem for second order linear ordinary differential equation. This algorithm requires O(N) arithmetical operations, where N is the number of subdivisions of considered interval. Error bounds for the solution are derived and numerical examples are given.
Źródło:
Mathematica Applicanda; 1992, 21, 35
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Weakly nonlinear boundaty value problems for differential systems with impulse action
Slabonelinejjnye kraevye zadachi dlja sistem differencial'nykh uravnenijj s impul'snym vozdejjstviem
Autorzy:
Ovchar, R.
Powiązania:
https://bibliotekanauki.pl/articles/76835.pdf
Data publikacji:
2013
Wydawca:
Komisja Motoryzacji i Energetyki Rolnictwa
Tematy:
nonlinear boundary value problem
linear boundary value problem
differential equation
Cauchy problem
Opis:
Coefficient obtained sufficient conditions for the existence and iterative algorithm of solutions of weakly nonlinear boundary value problems for ordinary differential equations with impulse action in general, when the number of boundary conditions does not coincide with the order of the differential system.
Коэффициенты получены с достаточных условий для существования и итерационного алгоритма решения через слабо нелинейни краеви задачи для обыкновенных дифференциальных уравнений с импульсным воздействием в общем случае, когда число граничных условий не совпадает с порядком дифференциального системы.
Źródło:
Motrol. Motoryzacja i Energetyka Rolnictwa; 2013, 15, 3
1730-8658
Pojawia się w:
Motrol. Motoryzacja i Energetyka Rolnictwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bessel matrix differential equations: explicit solutions of initial and two-point boundary value problems
Autorzy:
Navarro, Enrique
Company, Rafael
Jódar, Lucas
Powiązania:
https://bibliotekanauki.pl/articles/1340656.pdf
Data publikacji:
1993
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
initial value problem
closed form solution
fundamental set
boundary value problem
Bessel matrix equation
Opis:
In this paper we consider Bessel equations of the type $t^2 X^{(2)}(t) + t X^{(1)}(t) + (t^2 I - A^2)X(t) = 0$, where A is an n$\times$n complex matrix and X(t) is an n$\times$m matrix for t > 0. Following the ideas of the scalar case we introduce the concept of a fundamental set of solutions for the above equation expressed in terms of the data dimension. This concept allows us to give an explicit closed form solution of initial and two-point boundary value problems related to the Bessel equation.
Źródło:
Applicationes Mathematicae; 1993-1995, 22, 1; 11-23
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recovering a part of potential by partial information on spectra of boundary problems
Autorzy:
Pivovarchik, V.
Powiązania:
https://bibliotekanauki.pl/articles/255115.pdf
Data publikacji:
2005
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
sine-type function
Lagrange interpolation series
Dirichlet boundary value problem
Dirichlet-Neumann boundary value problem
Opis:
Under additional conditions uniqueness of the solution is proved for the following problem. Given 1) the spectrum of the Dirichlet problem for the Sturm-Liouville equation on [0, a] with real potential q(x) mem L2(0, a), 2) a certain part of the spectrum of the Dirichlet problem for the same equation on [a/3, a] and 3) the potential on [0, a/3]. The aim is to find the potential on [a/3 ,a].
Źródło:
Opuscula Mathematica; 2005, 25, 1; 131-137
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Positive solutions to nonlinear singular second order boundary value problems
Autorzy:
Bonanno, Gabriele
Powiązania:
https://bibliotekanauki.pl/articles/1310938.pdf
Data publikacji:
1996
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
singular boundary value problem
positive solution
Opis:
Existence theorems of positive solutions to a class of singular second order boundary value problems of the form y'' + f(x,y,y') = 0, 0 < x < 1, are established. It is not required that the function (x,y,z) → f(x,y,z) be nonincreasing in y and/or z, as is generally assumed. However, when (x,y,z) → f(x,y,z) is nonincreasing in y and z, some of O'Regan's results [J. Differential Equations 84 (1990), 228-251] are improved. The proofs of the main theorems are based on a fixed point theorem for weakly sequentially continuous operators.
Źródło:
Annales Polonici Mathematici; 1996, 64, 3; 237-251
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of influence of conservative and tangential axial forces on transverse vibrations of tapered vertical columns
Autorzy:
Jaroszewicz, J.
Radziszewski, L.
Dragun, Ł.
Powiązania:
https://bibliotekanauki.pl/articles/298148.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
transverse vibrations
vertical cantilever
boundary value problem
Opis:
The Cauchy function and characteristic series were applied to solve the boundary value problem of free transverse vibrations of vertically mounted, elastically supported tapered cantilever columns. The columns can be subjected to universal axial point loads which considerate – conservative and follower /tangential/ forces, and to distributed loads along the cantilever length. The general form of characteristic equation was obtained taking into account the shape of tapered cantilever for attached and elastically secured. Bernstein-Kieropian double and higher estimators of natural frequency and critical loads were calculated based on the first few coefficients of the characteristic series. Good agreement was obtained between the calculated natural frequency and the exact values available in the literature.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2017, 20(4); 333-342
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Conformal mapping of the domain bounded by a circular polygon with zero angles onto the unit disc
Autorzy:
Mityushev, Vladimir
Powiązania:
https://bibliotekanauki.pl/articles/1294434.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
conformal mapping
boundary value problem
functional equation
Opis:
The conformal mapping ω(z) of a domain D onto the unit disc must satisfy the condition |ω(t)| = 1 on ∂D, the boundary of D. The last condition can be considered as a Dirichlet problem for the domain D. In the present paper this problem is reduced to a system of functional equations when ∂D is a circular polygon with zero angles. The mapping is given in terms of a Poincaré series.
Źródło:
Annales Polonici Mathematici; 1998, 68, 3; 227-236
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Diffusions in one-dimensional bounded domains with reflection, absorption and jumps at the boundary and at some interior point
Autorzy:
Kopytko, B.
Shevchuk, R.
Powiązania:
https://bibliotekanauki.pl/articles/122365.pdf
Data publikacji:
2013
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
classical potential theory
boundary value problem
Feller semigroup
Opis:
By the method of classical potential theory, we obtain the integral representation of the two-parameter operator semigroup that describes the inhomogeneous Feller process on a closed interval [ r1,r2 ] that is a result of pasting together two diffusion processes given on ( r1,r, ) and ( r, r2 ), respectively, where - ∞ < r1 < r < r2 <∞ .
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2013, 12, 1; 55-68
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flow-induced Vibrations of a Horizontal Elastic Band Plate Submerged in Fluid of Finite Depth
Autorzy:
Szmidt, Kazimierz
Hedzielski, Benedykt
Powiązania:
https://bibliotekanauki.pl/articles/241049.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
elastic plate vibrations
surface waves
initial value problem
coupled problem
Opis:
The paper deals with forced vibrations of a horizontal thin elastic plate submerged in a semi-infinite layer of fluid of constant depth. The pressure load on this plate is induced by water waves arriving at the plate. This load is accompanied by pressure resulting from the motion of the plate. The plate and fluid motions depend on boundary conditions, and, in particular, the pressure load depends on the width of the gap between the plate and the bottom. In theoretical description of the phenomenon, we deal with a coupled problem of hydrodynamics in which the plate and fluid motions are coupled through boundary conditions at the plate surfaces. The main attention is focused on transient solutions of the problem, which correspond to fluid (and plate) motion starting from rest. In formulation of this problem, a linear theory of small deflections of the plate is employed. In order to calculate the fluid pressure, a solution of Laplace’s equation is constructed in a doubly connected fluid domain. With respect to the initial value problem considered, we confine our attention to a finite fluid domain. For a finite elapse of time, measured from the starting point, the solution in the finite fluid area mimics a solution within an infinite domain, inherent for wave propagation problems. Because of the complicated structure of boundary conditions of the coupled problem considered, the fluid domain is divided into sub-domains of simple geometry, and the solutions of the problem equations are constructed separately in each of these domains. Numerical experiments have been conducted to illustrate the formulation developed in this paper.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2019, 66, 3-4; 101-130
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Controllability theorem for nonlinear dynamical systems
Autorzy:
Kisielewicz, Michał
Powiązania:
https://bibliotekanauki.pl/articles/729548.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
differential equation
differential inclusions
controllability
boundary value problem
Opis:
Some sufficient conditions for controllability of nonlinear systems described by differential equation ẋ = f(t,x(t),u(t)) are given.
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2002, 22, 2; 225-232
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some remarks on exact solution of Lidstone boundary value problem
Pewne aspekty dotyczące jawnych rozwiązań zagadnienia brzegowego Lidstonea
Autorzy:
Jurkiewicz, M.
Powiązania:
https://bibliotekanauki.pl/articles/209397.pdf
Data publikacji:
2012
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
problem brzegowy Lidstone'a
wartość własna
Lidstone boundary value problem
eigenvalue
Opis:
In this paper we focus on the following form of the Lidstone BVP [formula]. We examine correlation between parameters λi ∈ R and the kernel of differential operaror that corresponds to the right hand side of the considered problem. Next we present a method of inverting the mentioned operator. In consequence of this method, we obtain two exact formulas that describe the corresponding Green's functions and the form of a solution with its derivatives in the case when ʃ depends only on t.
Celem pracy jest rozważenie pewnych aspektów egzystencjalnych dotyczących zagadnienia brzegowego Lidstone'a, postaci [wzór]. Jest widoczne, że problem istnienia rozwiązań zależy od części liniowej powyższego problemu. Dokładniej dla pewnego zestawu parametrów λi operator różniczkowy odpowiadający lewej stronie przedstawionego problemu może być odwracalny lub nie. W związku z tym praca została podzielona na dwie części, w pierwszej skupiamy się na wyznaczeniu k-wymiarowego widma oraz opisaniu jego własności. Druga część jest poświęcona podaniu metod wyznaczania jawnej postaci funkcji Greena dla powyższego problemu w zbiorze rezolwenty wspomnianego operatora różniczkowego.
Źródło:
Biuletyn Wojskowej Akademii Technicznej; 2012, 61, 4; 343-358
1234-5865
Pojawia się w:
Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties of some integrals related to partial differential equations of order higher than two
Autorzy:
Popiołek, Jan
Powiązania:
https://bibliotekanauki.pl/articles/1310757.pdf
Data publikacji:
1997
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
partial differential equation
boundary-value problem
Volterra integral equation
Opis:
We construct fundamental solutions of some partial differential equations of order higher than two and examine properties of these solutions and of some related integrals. The results will be used in our next paper concerning boundary-value problems for these equations.
Źródło:
Annales Polonici Mathematici; 1996-1997, 65, 2; 129-138
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On boundary-value problems for partial differential equations of order higher than two
Autorzy:
Popiołek, Jan
Powiązania:
https://bibliotekanauki.pl/articles/1310785.pdf
Data publikacji:
1997
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
partial differential equation
boundary-value problem
Volterra integral equation
Opis:
We prove the existence of solutions of some boundary-value problems for partial differential equations of order higher than two. The general idea is similar to that in [1]. We make an essential use of the results of our paper [12].
Źródło:
Annales Polonici Mathematici; 1996-1997, 65, 2; 139-150
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some existence results for solutions of differential inclusions with retardations
Autorzy:
Erbe, L.
Krawcewicz, W.
Chen, Shaozhu
Powiązania:
https://bibliotekanauki.pl/articles/1313253.pdf
Data publikacji:
1991
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
boundary value problem
differential inclusion with retardations
topological transversality
Opis:
Using the topological transversality method of Granas we prove an existence result for a system of differential inclusions with retardations of the form y'' ∈ F(t,y,y',Φ(y)). The result is applied to the study of the existence of solutions to an equation of the trajectory of an r-stage rocket with retardations.
Źródło:
Annales Polonici Mathematici; 1991, 54, 3; 227-239
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multiple positive solutions to singular boundary value problems for superlinear second order FDEs
Autorzy:
Jiang, Daqing
Powiązania:
https://bibliotekanauki.pl/articles/1207893.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
superlinear
fixed point theorem
singular boundary value problem
existence
Opis:
We study the existence of positive solutions to the singular boundary value problem for a second-order FDE

⎧ u'' + q(t) f(t,u(w(t))) = 0, for almost all 0 < t < 1,
⎨ u(t) = ξ(t), a ≤ t ≤ 0,
⎩ u(t) = η(t), 1 ≤ t ≤ b,

where q(t) may be singular at t = 0 and t = 1, f(t,u) may be superlinear at u = ∞ and singular at u = 0.
Źródło:
Annales Polonici Mathematici; 2000, 75, 3; 257-270
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Positive solutions to a third order nonlocal boundary value problem with a parameter
Autorzy:
Szajnowska, Gabriela
Zima, Mirosława
Powiązania:
https://bibliotekanauki.pl/articles/29519483.pdf
Data publikacji:
2024
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
boundary value problem
nonlocal boundary conditions
positive solution
cone
Opis:
We present some sufficient conditions for the existence of positive solutions to a third order differential equation subject to nonlocal boundary conditions. Our approach is based on the Krasnosel’skiĭ-Guo fixed point theorem in cones and the properties of the Green’s function corresponding to the BVP under study. The main results are illustrated by suitable examples.
Źródło:
Opuscula Mathematica; 2024, 44, 2; 267-283
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Performance Measure of a New One-Step Numerical Technique via Interpolating Function for the Solution of Initial Value Problem of First Order Differential Equation
Autorzy:
Fadugba, Sunday Emmanuel
Okunlola, Joseph Temitayo
Powiązania:
https://bibliotekanauki.pl/articles/1178790.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Initial value problem
Interpolating function
One-step numerical technique
Opis:
This paper presents the development of a new one-step numerical technique for the solution of initial value problems of first order differential equations by means of the interpolating function. The interpolating function used in this paper consists of both polynomial and exponential functions. Numerical experiments were performed to determine the efficiency and robustness of the scheme. The results show that the scheme is computationally efficient, robust and compares favourably with exact solutions.
Źródło:
World Scientific News; 2017, 90; 77-87
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Limitation of Cauchy function method in analysis for double estimators of free transversal vibration of cantilever tapered shafts
Autorzy:
Jaroszewicz, J.
Dragun, Ł
Powiązania:
https://bibliotekanauki.pl/articles/298463.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
cantilever shafts
transversal
vibrations
Cauchy function
boundary value problem
Opis:
In this paper the Bernstein-Kieropian simplest Dunkerly estimators of natural frequencies of cantilever shafts with power variable flexural rigidity and attached concentrated mass were analyzed in a theoretical approach. The approximate solution of boundary value problem of transversal vibrations by means of Cauchy function and characteristic series method has gave getting functional dependence between natural frequency and variable parameters of shafts. Particular attention has been given to a singularity arising from the uncertainty of estimates of Bernstein-Kieropian. Limitation of Cauchy function method in analysis double estimators of natural frequencies of transversal vibration of cantilever tapered shafts exude to exact theoretical selection using by Bessel’s function and experimental result received by Panuszka R., Uhl T.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2013, 16(2); 131-146
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of free vibrations of a continuous-discrete system with damping
Autorzy:
Cabański, J.
Powiązania:
https://bibliotekanauki.pl/articles/280635.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
vibrations
discrete-continuous models
damping
operator
boundary value problem
Opis:
In this paper a generalized exact method of solving the problem of beam free vibrations with a discrete rigid body attached to the beam by means of viscoelastic constraints was presented. The vibrations of such a discrete-continuous system were described by a set of coupled partial and ordinary differential equations. Separation of the variables and the obtained results of the boundary-value problem, as well as the proved generalized orthogonality of complex eigenmodes, were used to the analysis of free vibrations of the system with arbitrary initial conditions.
Analiza drań swobodnych układu ciągło-dyskretnego z tłumieniem. W pracy przedstawiono uogólnioną ścisłą metodę rozwiązania zagadnienia drgań swobodnych belki z dołączonymi do niej, za pośrednictwem lepko-sprężystych więzi, skoncentrowanymi sztywnymi ciałami. Drgania układu ciągło-dyskretnego zostały opisane układem sprzężonym, tj. jednym częastkowym i dwoma podukładami zwyczjnych równań różniczkowych. Rozdzielenie zmiennych i wyniki uzyskane z rozwiązania problemu brzegowego oraz warunek ortogonalności postaci drgań własnych wykorzystano do analizy drgań swobodnych tego układu mechanicznego przy dowolnych warunkach początkowych.
Źródło:
Journal of Theoretical and Applied Mechanics; 2001, 39, 1; 195-212
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Asymptotic study of elastic half-plane with embedded punch
Analiza asymtotyczna zagadnienia kontaktowego stempla i półprzestrzeni sprężystej
Autorzy:
Andrianov, I. V.
Awrejcewicz, J.
Kirichek, Yu. A.
Koblik, S. G.
Powiązania:
https://bibliotekanauki.pl/articles/280842.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
mixed boundary value problem
singular asymptotics
complex variable theory
Opis:
A contact problem for an elastic half-plane and an embedded rigid punch is studied. The employed mathematical model describes the behavior of a soil with embedded foundation. The analytical solution geverning the stress field behaviour is derived. Singular perturbation and complex analysis techniques are used.
W pracy rozważono zagadnienie kontaktowe związane z oddziaływaniem sztywnego stempla i półprzestrzeni sprężystej. Analizowany problem może np. modelować fundamenty budowli usytuowane w podatnym gruncie. Sformułowano w postaci analitycznej pole naprężeń przy użyciu metody perturbacji osobliwych i techniki zmiennych zespolonych.
Źródło:
Journal of Theoretical and Applied Mechanics; 2007, 45, 1; 5-14
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The use of integral information in the solution of a two-point boundary value problem
Autorzy:
Drwięga, T.
Powiązania:
https://bibliotekanauki.pl/articles/255474.pdf
Data publikacji:
2007
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
boundary value problem
complexity
worst case setting
linear information
Opis:
We study the worst-case ε-complexity of a two-point boundary value problem u″(x) = ƒ(x) u (x), x ∈ [0,T], u(0) = c, u′ (T) = 0, where c,T ∈ R (c ≠ 0, T > 0) and ƒ is a nonnegative function with r (r ≥ 0) continuous bounded derivatives. We prove an upper bound on the complexity for linear information showing that a speed-up by two orders of magnitude can be obtained compared to standard information. We define an algorithm based on integral information and analyze its error, which provides an upper bound on the ε-complexity.
Źródło:
Opuscula Mathematica; 2007, 27, 2; 205-220
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On a comparison principle for a quasilinear elliptic boundary value problem of a nonmonotone type
Autorzy:
Křížek, Michal
Liu, Liping
Powiązania:
https://bibliotekanauki.pl/articles/1339322.pdf
Data publikacji:
1996
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
comparison principle
anisotropic heat conduction
nonlinear boundary value problem
Opis:
A nonlinear elliptic partial differential equation with the Newton boundary conditions is examined. We prove that for greater data we get a greater weak solution. This is the so-called comparison principle. It is applied to a steady-state heat conduction problem in anisotropic magnetic cores of large transformers.
Źródło:
Applicationes Mathematicae; 1996-1997, 24, 1; 97-107
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wave Generation by a Finite Baffle Array in Application to Beam-Forming Analysis
Autorzy:
Tasinkevych, Y.
Powiązania:
https://bibliotekanauki.pl/articles/177857.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
phased array
beamforming
mixed boundary value problem
BIS expansion
Opis:
Directional excitation of sound in an aperiodic finite baffle system is analyzed using a method developed earlier in electrostatics. The solution to the corresponding boundary value problem is obtained in the spatial-frequency domain. The acoustic pressure and normal particle velocity distribution in acoustic media can be easily computed by the inverse Fourier transform from their spatial spectra on the baffle plane. The presented method can be used for linear acoustic phased arrays modeling with finite element size and inter-element interactions taken into account. Some illustrative numerical examples presenting the far-field radiation pattern and wavebeam steering are given.
Źródło:
Archives of Acoustics; 2010, 35, 4; 677-686
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On some elliptic operator of order one
O pewnym operatorze eliptycznym pierwszego rzędu
Autorzy:
Kołakowski, J. H.
Powiązania:
https://bibliotekanauki.pl/articles/209610.pdf
Data publikacji:
2008
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
zagadnienia poprawnie postawione
zagadnienie transmisji
well posed boundary value problem
transmission problem
Opis:
The purpose of this paper is to determine explicitly wellposed transmission problems for some elliptic system. It is well known that for this system there is no wellposed boundary value problem in any bounded domain in R⁴.
Celem tej pracy jest wydzielenie pewnej klasy dobrze postawionych zagadnień transmisji dla operatora eliptycznego o którym wiadomo, że nie istnieje dla niego dobrze postawione zagadnienie brzegowe i to na dowolnym obszarze.
Źródło:
Biuletyn Wojskowej Akademii Technicznej; 2008, 57, 4; 95-99
1234-5865
Pojawia się w:
Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An intial-value technique for self-adjoint singularly perturbed two-point boundary value problems
Autorzy:
Padmaja, P.
Aparna, P.
Gorla, R. S. R.
Powiązania:
https://bibliotekanauki.pl/articles/264933.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
wartość początkowa
wartość brzegowa
perturbacja procesu
initial value technique
boundary value problem
singular perturbation problem
Opis:
In this paper, we present an initial value technique for solving self-adjoint singularly perturbed linearvboundary value problems. The original problem is reduced to its normal form and the reduced problem is converted to first order initial value problems. This replacement is significant from the computational point of view. The classical fourth order Runge-Kutta method is used to solve these initial value problems. This approach to solve singularly perturbed boundary-value problems is numerically very appealing. To demonstrate the applicability of this method, we have applied it on several linear examples with left-end boundary layer and rightend layer. From the numerical results, the method seems accurate and solutions to problems with extremely thin boundary layers are obtained.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 1; 106-126
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Semilinear evolution equations of the parabolic type
Autorzy:
Bochenek, Jan
Powiązania:
https://bibliotekanauki.pl/articles/1293838.pdf
Data publikacji:
1999
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
classical solution
semilinear initial value problem
analytic semigroup
mild solution
Opis:
This paper is devoted to the investigation of the abstract semilinear initial value problem du/dt + A(t)u = f(t,u), u(0) = u₀, in the "parabolic" case.
Źródło:
Annales Polonici Mathematici; 1999, 72, 3; 197-206
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Monotone iterative technique for fractional differential equations with periodic boundary conditions
Autorzy:
Ramirez, J. D.
Vatsala, A. S.
Powiązania:
https://bibliotekanauki.pl/articles/255247.pdf
Data publikacji:
2009
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
Riemann-Liouville fractional derivative
monotone method
periodic boundary value problem
Opis:
In this paper we develop Monotone Method using upper and lower solutions for fractional differential equations with periodic boundary conditions. Initially we develop a comparison result and prove that the solution of the linear fractional differential equation with periodic boundary condition exists and is unique. Using this we develop iterates which converge uniformly monotonically to minimal and maximal solutions of the nonlinear fractional differential equations with periodic boundary conditions in the weighted norm.
Źródło:
Opuscula Mathematica; 2009, 29, 3; 289-304
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A general boundary value problem and its Weyl function
Autorzy:
Ryzhov, V.
Powiązania:
https://bibliotekanauki.pl/articles/255861.pdf
Data publikacji:
2007
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
abstract boundary value problem
symmetric operators
Green formula
Weyl function
Opis:
We study the abstract boundary value problem defined in terms of the Green identity and introduce the concept of Weyl operator function M(·) that agrees with other definitions found in the current literature. In typical cases of problems arising from the multidimensional partial equations of mathematical physics the function M(·) takes values in the set of unbounded densely defined operators acting on the auxiliary boundary space. Exact formulae are obtained and essential properties of M(·) are studied. In particular, we consider boundary problems defined by various boundary conditions and justify the well known procedure that reduces such problems to the "equation on the boundary" involving the Weyl function, prove an analogue of the Borg-Levinson theorem, and link our results to the classical theory of extensions of symmetric operators.
Źródło:
Opuscula Mathematica; 2007, 27, 2; 305-331
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polynomial quasisolutions of linear differential-difference equations
Autorzy:
Cherepennikov, V. B.
Ermolaeva, P. G.
Powiązania:
https://bibliotekanauki.pl/articles/255903.pdf
Data publikacji:
2006
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
differential-difference equations
neutral type
initial-value problem
polynomial quasisolution
Opis:
The paper discusses a linear differential-difference equation of neutral type with linear coefficients, when at the initial time moment t = 0 the value of the desired function x(t) is known. The authors are not familiar with any results which would state the solvability conditions for the given problem in the class of analytical functions. A polynomial of some degree N is introduced into the investigation. Then the term "polynomial quasisolution" (PQ-solution) is understood in the sense of appearance of the residual Δ(t) = O(tN), when this polynomial is substituted into the initial problem. The paper is devoted to finding PQ-solutions for the initial-value problem under analysis.
Źródło:
Opuscula Mathematica; 2006, 26, 3; 431-443
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exact difference schemes and schemes of higher order of approximation for convection-diffusion equation. I
Autorzy:
Lapinska-Chrzczonowicz, M.
Matus, P.
Powiązania:
https://bibliotekanauki.pl/articles/106186.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
convection-diffusion equation
initial-boundary value problem
traveling wave
EDS
Opis:
The initial-boundary value problem for a convection-diffusion equation [formula] is considered. The difference scheme, approximating this problem, is constructed. It is shown that for traveling wave solutions the scheme is exact (EDS). The monotonicity of the scheme is also taken into consideration. Presented numerical experiments illustrate the theoretical results investigated in the paper.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska. Sectio AI, Informatica; 2013, 13, 1; 37-51
1732-1360
2083-3628
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska. Sectio AI, Informatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Approximate controllability for systems described by right invertible operators
Autorzy:
Hoang, V. T.
Powiązania:
https://bibliotekanauki.pl/articles/971010.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
zagadnienie początkowe
right invertible operator
initial operator
initial-value problem
Opis:
In this paper, we deal with the approximate controllability for linear systems described by right invertible operators in an infinite dimensional Banach space.
Źródło:
Control and Cybernetics; 2008, 37, 1; 39-50
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the influence of elasticity constants and material density on the base frequency of axi-symmetrical vibrations with variable thickness plates
Analiza wpływu stałych sprężystych i gęstości materiału na częstość podstawową drgań osiowosymetrycznych płyt kołowych o zmiennej grubości
Autorzy:
Domoradzki, M.
Jaroszewicz, J.
Zoryj, L.
Powiązania:
https://bibliotekanauki.pl/articles/279707.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
circular plates
variable thickness
boundary value problem
Cauchy function method
Opis:
In the paper, the influence of Young's modulus and Poisson ratio as well as mass density of a material on the base frequency of circular plates of the diaphragm type with variable thickness is discussed. In order to solve the boundary-value problem, the Cauchy function method and double Bernstein-Kieropian estimators were applied. An analytical form of Cauchy's influence function was found and used to construct the characteristic equation in the form of a power series with respect to a frequency parameter. Application of this method allowed a functional dependency of the base frequency on material constants of the plates to be established. The results of calculations for plates made of duralumin and tin were mentioned as examples. Comparison of the obtained results with those found in scientific literature indicated high accuracy of the method applied therein.
W pracy zbadano wpływ modułu sprężystości Younga i liczby Poissona, a także gęstości materiału na częstość podstawową płyt o zmiennej grubości typu diafragmy i dysku. Do rozwiązania zagadnienia brzegowego zastosowano metodę funkcji wpływu Cauchy, najprostszy estimator z niedostatkiem i dwustronne estymatory Bernstejna-Kieropiana. Znaleziono analityczną postać funkcji wpływu Cauchy, z pomocą której zbudowano równanie charakterystyczne w postaci szeregu potęgowego względem parametru częstotliwości. Zastosowanie metody pozwoliło wyprowadzić funkcjonalną zależność częstości podstawowej od stałych materiałowych wymienionych płyt. W charakterze przykładu przytoczono wyniki obliczeń dla płyt wykonanych z duraluminium i z cyny. Porównanie wyników obliczen ze znanymi z literatury potwierdziły wysoką dokładność metody.
Źródło:
Journal of Theoretical and Applied Mechanics; 2005, 43, 4; 763-775
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multiple solutions for systems of multi-point boundary value problems
Autorzy:
Graef, J. R.
Heidarkhani, S.
Kong, L.
Powiązania:
https://bibliotekanauki.pl/articles/255713.pdf
Data publikacji:
2013
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
multiple solutions
multi-point boundary value problem
critical point theory
Opis:
In this paper, we establish the existence of at least three solutions of the multi-point boundary value system [formula]. The approaches used are based on variational methods and critical point theory.
Źródło:
Opuscula Mathematica; 2013, 33, 2; 293-306
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An abstract semilinear first order differential equation in the hyperbolic case
Autorzy:
Bochenek, Jan
Powiązania:
https://bibliotekanauki.pl/articles/1311559.pdf
Data publikacji:
1995
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
semilinear initial value problem
stable family of operators
hyperbolic case
Opis:
This paper is devoted to the investigation of the abstract semilinear initial value problem $du/dt = A(t)u + f(t,u), u(0) = u_0$, in the "hyperbolic" case.
Źródło:
Annales Polonici Mathematici; 1995, 61, 1; 13-23
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Granular Derivatives and the Solution of a Granular Initial Value Problem
Autorzy:
Batyrshin, I.
Powiązania:
https://bibliotekanauki.pl/articles/908040.pdf
Data publikacji:
2002
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
informatyka
fuzzy differential
fuzzy granule
initial value problem
cylindrical extension
Opis:
Perceptions about function changes are represented by rules like "If X is SMALL then Y is QUICKLY INCREASING." The consequent part of a rule describes a granule of directions of the function change when X is increasing on the fuzzy interval given in the antecedent part of the rule. Each rule defines a granular differential and a rule base defines a granular derivative. A reconstruction of a fuzzy function given by the granular derivative and the initial value given by the rule is similar to Euler's piecewise linear solution of an initial value problem. The solution method is based on a granulation of the directions of the function change, on an extension of the initial value in directions and on a propagation of fuzzy constraints given in antecedent parts of rules on possible function values. The proposed method is illustrated with an example.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2002, 12, 3; 403-410
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mathematical modelling of the inrun profile of a ski jumping hill with the controlled track reaction force
Modelowanie profilu najazdu skoczni narciarskiej o zadanych własnościach dynamicznych toru
Autorzy:
Palej, R.
Filipowska, R.
Powiązania:
https://bibliotekanauki.pl/articles/280261.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
inrun profile
ski jumping hill
nonlinear boundary value problem
shooting method
Opis:
The paper deals with the problem of modelling the inrun profile of a ski jumping hill with a variable radius of curvature. It presents the possibility of reducing the inertia force acting on a ski jumper in the immediate neighbourhood of the take-off track while maintaining the inclination angles of the starting segment of the track and the take-off track which are applied in the present day constructions. The problem of a further decrease of the inertia force resulting from the increase of the inclination angle of the starting segment has also been discussed. Finally, the profiles of the inrun which do not contain the inflexion point have been determined.
Praca dotyczy zagadnienia projektowania najazdu skoczni narciarskiej o zmiennym promieniu krzywizny. W pracy pokazano możliwość obniżenia reakcji normalnej toru w bezpośrednim sąsiedztwie z progiem, przy zachowaniu stosowanych w obecnych rozwiązaniach kątów nachylenia części startowej i progu. Zbadano również możliwość dalszego obniżenia reakcji normalnej w wyniku zwiększenia kąta nachylenia części startowej. Na koniec wyznaczono łagodne pod względem dynamicznym profile najazdu nie zawierające punktu przegięcia.
Źródło:
Journal of Theoretical and Applied Mechanics; 2009, 47, 1; 229-242
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fundamental solution of the problem describing ship motion in waves
Autorzy:
Jankowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/255889.pdf
Data publikacji:
2006
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
ship hydrodynamics
boundary value problem
free-surface potential flows
fundamental solution
Opis:
The problem describing a ship motion in waves comprises the Laplace equation, boundary condition on wetted surface of the ship, condition on the free surface of the sea in the form of a differential equation, the radiation condition, and a condition at infinity. This problem can be transformed to a Fredholm equation of second kind, and then numerically solved using the boundary element method, if the fundamental solution of the problem is known. This paper presents the derivation of the fundamental solution. In physical interpretation, the fundamental solution represents the moving and pulsating source under free surface of the sea. The free surface elevation, generated by the source for different forward speed and frequency of pulsation, is presented in this paper.
Źródło:
Opuscula Mathematica; 2006, 26, 3; 471-481
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence of a solution for the fractional forced pendulum
Autorzy:
Torres, C.
Powiązania:
https://bibliotekanauki.pl/articles/122603.pdf
Data publikacji:
2014
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
fractional calculus
fractional boundary value problem
mountain pass theorem
fractional space
Opis:
In this work we study the fractional forced pendulum equation with combined fractional derivatives - tDαT 0Dαt u( t ) + g ( u ( t )) = f ( t ), t ∈ ( 0, T ) ( 0. 1 ) u ( 0 ) = u ( T ) = 0 where ½ < α < 1, g ∈ C ( R, R ), bounded f ∈ C [ 0, T ]. Using minimization techniques form variational calculus we show that ( 0. 1 ) has a nontrivial solution.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2014, 13, 1; 125-142
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A note on a fourth order discrete boundary value problem
Autorzy:
Galewski, M.
Smejda, J.
Powiązania:
https://bibliotekanauki.pl/articles/255355.pdf
Data publikacji:
2012
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
discrete boundary value problem
variational method
coercivity
continuous dependence on paremeters
Opis:
Using variational methods we investigate the existence of solutions and their dependence on parameters for certain fourth order difference equations.
Źródło:
Opuscula Mathematica; 2012, 32, 1; 115-123
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On initial value problems for a class of first order impulsive differential inclusions
Autorzy:
Benchohra, Mouffak
Boucherif, Abdelkader
Nieto, Juan
Powiązania:
https://bibliotekanauki.pl/articles/729298.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
impulsive initial value problem
set-valued map
condensing map
fixed point
Opis:
We investigate the existence of solutions to first order initial value problems for differential inclusions subject to impulsive effects. We shall rely on a fixed point theorem for condensing maps to prove our results.
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2001, 21, 2; 159-171
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Limitations in application of basic frequency simplest lower estimators in investigation of natural vibrations of circular plates with variable thickness and clamped edges
Ograniczenia w stosowaniu najprostszych dolnych estymatorów częstości podstawowej w badaniu drgań własnych płyt kołowych typu diafragma
Autorzy:
Jaroszewicz, J.
Misiukiewicz, M.
Puchalski, W.
Powiązania:
https://bibliotekanauki.pl/articles/281790.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
płyty kołowe
zmienna grubość
problem wartości granicznej
circular plates
variable thickness
boundary value problem
Opis:
In this paper, we discussed the effects of application the Bernstein-Keropian simplest lower estimators for calculation of basic natural vibration frequencies of variable-thickness cir- cular plates. Following a thorough analysis, we showed a significant role of the operators of the 4th order Euler equations of motion describing vibrations of circular plates with exponentially variable thickness. The dependence of solutions on values of the variable thickness power index of the plate and Poisson’s ratio of the plate material was investigated. The variable power thickness diaphragm model was verified by FEM which confirmed the usefulness of the simplest estimator for following materials: titanium, steel, zinc. Comparison of the results obtained after applying the simplest lower estimators for the basic frequency with the results of exact solutions for particular cases found in the literature, confirmed high accuracy of the applied method.
W pracy omówiono efekt zastosowania naj prostszych estymatorów BernstejnaKieropiana do obliczania podstawowej częstości osiowosymetrycznych drgań własnych płyt o zmiennej grubości typu diafragma. Przeanalizowano i uwypuklono istotną rolę operatorów równań Eulera czwartego rzędu oraz ich fundamentalnej funkcji w osiowosymetrycznych zagadnieniach drgań płyt kołowych o potęgowo zmiennej grubości. Zbadano zależność rozwiązania od wartości wskaźnika zmiany grubości płyty i liczby Poissona. Weryfikacja modelu diafragm o potęgowo zmiennej grubości przy pomocy MES potwierdziła możliwość zastosowania naj prostszego estymatora w przypadku metali: tytanu, stali, cynku. Porównanie wyników obliczeń najprostszych estymatorów z dołu częstości podstawowej uzyskanych przy wykorzystaniu zaproponowanej metody oraz przy zastosowaniu znanych z literatury rozwiązań ścisłych dla szczególnych przypadków zmiany grubości płyty potwierdziło wysoką dokładność proponowanej metody.
Źródło:
Journal of Theoretical and Applied Mechanics; 2008, 46, 1; 109-121
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fourier-like methods for equations with separable variables
Autorzy:
Przeworska-Rolewicz, Danuta
Powiązania:
https://bibliotekanauki.pl/articles/729392.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
algebraic analysis
commutative algebra with unit
Leibniz condition
logarithmic mapping
antilogarithmic mapping
right invertible operator
sine mapping
cosine mapping
initial value problem
boundary value problem
Fourier method
Opis:
It is well known that a power of a right invertible operator is again right invertible, as well as a polynomial in a right invertible operator under appropriate assumptions. However, a linear combination of right invertible operators (in particular, their sum and/or difference) in general is not right invertible. It will be shown how to solve equations with linear combinations of right invertible operators in commutative algebras using properties of logarithmic and antilogarithmic mappings. The used method is, in a sense, a kind of the variables separation method. We shall obtain also an analogue of the classical Fourier method for partial differential equations. Note that the results concerning the Fourier method are proved under weaker assumptions than these obtained in [6] (cf. also [7, 8, 11]).
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2009, 29, 1; 19-42
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Right focal boundary value problems for difference equations
Autorzy:
Henderson, J.
Liu, X.
Lyons, J. W.
Neugebauer, J. T.
Powiązania:
https://bibliotekanauki.pl/articles/255580.pdf
Data publikacji:
2010
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
difference equation
boundary value problem
right focal
fixed point theorem
positive solution
Opis:
An application is made of a new Avery et al. fixed point theorem of compression and expansion functional type in the spirit of the original fixed point work of Leggett and Williams, to obtain positive solutions of the second order right focal discrete boundary value problem. In the application of the fixed point theorem, neither the entire lower nor entire upper boundary is required to be mapped inward or outward. A nontrivial example is also provided.
Źródło:
Opuscula Mathematica; 2010, 30, 4; 447-456
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulation of liquid motion in a partly filled tank
Autorzy:
Warmowska, M.
Powiązania:
https://bibliotekanauki.pl/articles/255682.pdf
Data publikacji:
2006
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
nonlinear boundary value problem
linear elliptic equations
sloshing
free-surface potential flows
Opis:
The paper presents the problem of liquid motion in a 2D partly filled tank. It is assumed that the flow of liquid in tank is a potential, hence it can be described by Laplace equations with appropriate boundary conditions. The problem is solved using the boundary element method. The developed numerical algorithm makes it possible to determine the free surface elevation, the velocity field and the pressure field during the liquid motion in the tank. The area occupied by liquid is represented by a mesh changing in time. Numerical computations are performed for translatory and rotational motion of the tank. The results of numerical computations are verified by experiment.
Źródło:
Opuscula Mathematica; 2006, 26, 3; 529-540
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the Kuramoto-Sivashinsky equation in a disk
Autorzy:
Varlamov, Vladimir
Powiązania:
https://bibliotekanauki.pl/articles/1208011.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
first initial-boundary value problem
long-time asymptotics
Kuramoto-Sivashinsky equation
disk
Opis:
We consider the first initial-boundary value problem for the 2-D Kuramoto-Sivashinsky equation in a unit disk with homogeneous boundary conditions, periodicity conditions in the angle, and small initial data. Apart from proving the existence and uniqueness of a global in time solution, we construct it in the form of a series in a small parameter present in the initial conditions. In the stable case we also obtain the uniform in space long-time asymptotic expansion of the constructed solution and its asymptotics with respect to the nonlinearity constant. The method can work for other dissipative parabolic equations with dispersion.
Źródło:
Annales Polonici Mathematici; 2000, 73, 3; 227-256
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical solutions to boundary value problem for anomalous diffusion equation with Riesz-Feller fractional operator
Numeryczne rozwiązanie zagadnienia brzegowego równania anomalnej dyfuzji z operatorem frakcjalnym Riesza-Fellera
Autorzy:
Ciesielski, M.
Leszczyński, J.
Powiązania:
https://bibliotekanauki.pl/articles/280627.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
Riesz-Feller fractional derivative
boundary value problem
Dirichlet conditions
finite difference method
Opis:
In this paper, we present a numerical solution to an ordinary differential equation of a fractional order in one-dimensional space. The solution to this equation can describe a steady state of the process of anomalous diffusion. The process arises from interactions within complex and non-homogeneous background. We present a numerical method which is based on the finite differences method. We consider a boundary value problem (Dirichlet conditions) for an equation with the Riesz-Feller fractional derivative. In the final part of this paper, some simulation results are shown. We present an example of non-linear temperature profiles in nanotubes which can be approximated by a solution to the fractional differential equation.
W pracy zaprezentowano numeryczne rozwiązanie jednowymiarowego równania różniczkowego zwyczajnego niecałkowitego rzędu. Rozwiązanie tego równania może opisywać stan ustalony procesu anomalnej dyfuzji. Proces ten wynika z oddziaływań zachodzących w złożonych i niejednorodnych systemach. Zaprezentowana metoda numeryczna oparta jest na metodzie różnic skończonych. Rozważane było zagadnieriie brzegowe z warunkami Dirichleta dla tego równania z pochodną frakcjalną RieszaFellera. W końcowej części przedstawiono wyniki symulacji. Jako przykład zaprezentowano nieliniowy profil temperatury w nanorurkach, który może być przybliżony przez rozwiązanie frakcjalnego równania różniczkowego.
Źródło:
Journal of Theoretical and Applied Mechanics; 2006, 44, 2; 393-403
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence theorems of nonlinear asymptotic BVP for a homeomorphism
Autorzy:
Szymańska-Dębowska, K.
Powiązania:
https://bibliotekanauki.pl/articles/255486.pdf
Data publikacji:
2016
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
half-line
nonlinear
asymptotic boundary value problem
phi-Laplacian
Leray-Schauder degree
Opis:
In this work, we are concerned with the existence of solutions for the following φ -Laplacian boundary value problem on the half-line [formula] where [formula] is continuous. The results are proved using the properties of the Leray-Schauder topological degree.
Źródło:
Opuscula Mathematica; 2016, 36, 3; 399-407
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multiple positive solutions of a nonlinear fourth order periodic boundary value problem
Autorzy:
Kong, Lingbin
Jiang, Daqing
Powiązania:
https://bibliotekanauki.pl/articles/1294291.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
nonlinear periodic boundary value problem
multiple positive solutions
cone
fixed point index
Opis:
The fourth order periodic boundary value problem $u^{(4)} - m⁴u + F(t,u) = 0$, 0 < t < 2π, with $u^{(i)}(0) = u^{(i)}(2π)$, i = 0,1,2,3, is studied by using the fixed point index of mappings in cones, where F is a nonnegative continuous function and 0 < m < 1. Under suitable conditions on F, it is proved that the problem has at least two positive solutions if m ∈ (0,M), where M is the smallest positive root of the equation tan mπ = -tanh mπ, which takes the value 0.7528094 with an error of $±10^{-7}$.
Źródło:
Annales Polonici Mathematici; 1998, 69, 3; 265-270
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Rough Estimation of Acoustics of the Cuboidal Room with Impedance Walls
Autorzy:
Kocan-Krawczyk, A.
Brański, A.
Powiązania:
https://bibliotekanauki.pl/articles/177714.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Fourier analysis
room acoustics
absorption coefficient
boundary-value problem
impedance boundary conditions
Opis:
The cuboidal room acoustics field is modelled with the Fourier method. A combination of uniform, impedance boundary conditions imposed on walls is assumed, and they are expressed by absorption coefficient values. The absorption coefficient, in the full range of its values in the discrete form, is considered. With above assumptions, the formula for a rough estimation of the cuboidal room acoustics is derived. This approximate formula expresses the mean sound pressure level as a function of the absorption coefficient, frequency, and volume of the room separately. It is derived based on the least-squares approximation theory and it is a novelty in the cuboidal room acoustics. Theoretical considerations are illustrated via numerical calculations performed for the 3D acoustic problem. Quantitative results received with the help of the approximate formula may be a point of reference to the numerical calculations.
Źródło:
Archives of Acoustics; 2018, 43, 2; 227-233
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical Analysis and Experimental Verification of Top Orthogonal to Bottom Arrays of Conducting Strips on Piezoelectric Slab
Autorzy:
Tasinkevych, Yuriy
Trots, Ihor
Tymkiewicz, Ryszard
Powiązania:
https://bibliotekanauki.pl/articles/178024.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
boundary value problem
Fourier series
Bloch series
partial differential equations
piezoelectric transducer
Opis:
The purpose of this work is to present a theoretical analysis of top orthogonal to bottom arrays of conducting electrodes of infinitesimal thickness (conducting strips) residing on the opposite surfaces of piezoelectric slab. The components of electric field are expanded into double periodic Bloch series with corresponding amplitudes represented by Legendre polynomials, in the proposed semi-analytical model of the considered two-dimensional (2D) array of strips. The boundary and edge conditions are satisfied directly by field representation, as a result. The method results in a small system of linear equations for unknown expansion coefficients to be solved numerically. A simple numerical example is given to illustrate the method. Also a test transducer was designed and a pilot experiment was carried out to illustrate the acoustic-wave generating capabilities of the proposed arrangement of top orthogonal to bottom arrays of conducting strips.
Źródło:
Archives of Acoustics; 2020, 45, 3; 433-444
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Greens operator to quadratic variational problems
Autorzy:
Azbelev, N. V.
Tsalyuk, V. Z.
Powiązania:
https://bibliotekanauki.pl/articles/255629.pdf
Data publikacji:
2006
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
quadratic variational problem
Sobolev space
boundary value problem
Hilbert space
Green's operator
Fredholm integral operator
spectrum
Opis:
We use Green's function of a suitable boundary value problem to convert the variational problem with quadratic functional and linear constraints to the equivalent unconstrained extremal problem in some subspace of the space L2 of quadratically summable functions. We get the neccessary and sufficient criterion for unique solvability of the variational problem in terms of the spectrum of some integral Hilbert-Schmidt operator in L2 with symmetric kernel. The numerical technique is proposed to estimate this criterion. The results are demonstrated on examples: 1) a variational problem with deviating argument, and 2) the problem of the critical force for the vertical pillar with additional support point (the qualities of the pillar may vary discontinuously along the pillar's axis).
Źródło:
Opuscula Mathematica; 2006, 26, 2; 243-256
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Local controllability of nonlinear discrete-time fractional order systems
Autorzy:
Mozyrska, D.
Pawłuszewicz, E.
Powiązania:
https://bibliotekanauki.pl/articles/201944.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
fractional difference operator
fractional difference initial value problem
nonlinear fractional order system
linear approximation
controllability problem
Opis:
The Riemann-Liouville, Caputo and Gr¨unwald-Letnikov fractional order difference operators are discussed and used to state and solve the controllability problem of a nonlinear fractional order discrete-time system. It is shown that independently of the type of fractional order difference, such a system is locally controllable in q steps if its linear approximation is globally controllable in q steps.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2013, 61, 1; 251-256
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of mathematical models for vibrations of one dimensional environments with considering nonlinear resistance forces
Autorzy:
Pukach, P.
Sokhan, P.
Stolyarchuk, R.
Powiązania:
https://bibliotekanauki.pl/articles/410895.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Oddział w Lublinie PAN
Tematy:
mathematical model
nonlinear vibrations
nonlinear boundary value problem
Galerkin method
nonlinear elastic properties
Opis:
In this paper we consider important classes of one dimensional environments, bending stiffness of which can be neglected. It is impossible to apply approximate analytical method of solution of mathematical models of dynamic processes. So justification of existence and uniqueness of solutions, carried out a qualitative their evaluation, based on numerical analysis are considering in this paper. Also the features of dynamic processes of some of examined class of systems are analyzed. Methods of qualitative study of oscillations for restricted and unrestricted bodies under the influence of the resistance forces, described in this paper are based on the general principles of the theory of nonlinear boundary value problems – Galerkin method and the method of monotonicity. Scientific novelty consists in generalization these methods of studying for nonlinear problems at new classes of oscillating systems, justification of solution correctness for specified mathematical models that have practical application in real engineering vibration systems.
Źródło:
ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes; 2016, 5, 1; 97-102
2084-5715
Pojawia się w:
ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On strongly monotone flows
Autorzy:
Walter, Wolfgang
Powiązania:
https://bibliotekanauki.pl/articles/1294817.pdf
Data publikacji:
1997
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
system of ordinary differential equations
initial value problem
comparison theorem
monotone flow
quasimonotonicity
Opis:
M. Hirsch's famous theorem on strongly monotone flows generated by autonomous systems u'(t) = f(u(t)) is generalized to the case where f depends also on t, satisfies Carathéodory hypotheses and is only locally Lipschitz continuous in u. The main result is a corresponding Comparison Theorem, where f(t,u) is quasimonotone increasing in u; it describes precisely for which components equality or strict inequality holds.
Źródło:
Annales Polonici Mathematici; 1997, 66, 1; 269-274
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On nonexistence of global in time solution for a mixed problem for a nonlinear evolution equation with memory generalizing the Voigt-Kelvin rheological model
Autorzy:
Pukach, P.
Il'kiv, V.
Nytrebych, Z.
Vovk, M.
Powiązania:
https://bibliotekanauki.pl/articles/255696.pdf
Data publikacji:
2017
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
boundary value problem
beam vibrations
nonlinear evolution equation
Voigt-Kelvin model
memory
blowup
Opis:
The paper deals with investigating of the first mixed problem for a fifth-order nonlinear evolutional equation which generalizes well known equation of the vibrations theory. We obtain sufficient conditions of nonexistence of a global solution in time variable.
Źródło:
Opuscula Mathematica; 2017, 37, 5; 735-753
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On differential inclusions of velocity hodograph type with Carathéodory conditions on Riemannian manifolds
Autorzy:
Gliklikh, Yuri
Obukhovski, Andrei
Powiązania:
https://bibliotekanauki.pl/articles/729628.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
differential inclusions
Carathéodory conditions
velocity hodograph
Riemannian manifold
two-point bounadry value problem
Opis:
We investigate velocity hodograph inclusions for the case of right-hand sides satisfying upper Carathéodory conditions. As an application we obtain an existence theorem for a boundary value problem for second-order differential inclusions on complete Riemannian manifolds with Carathéodory right-hand sides.
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2004, 24, 1; 41-48
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Matrix Greens function of double-diffusivity problem and its applications to problems with inner point source
Autorzy:
Chaplya, Yevhen
Chernukha, Olha
Bilushchak, Yurii
Powiązania:
https://bibliotekanauki.pl/articles/1954454.pdf
Data publikacji:
2014
Wydawca:
Politechnika Gdańska
Tematy:
Green’s function
double-diffusivity
initial-boundary value problem
point mass source
random coordinate
Opis:
The matrix Green’s function of the initial-boundary value problem of admixture double-diffusivity is defined. The initial-boundary value problem with a point source is formulated for the matrix elements for determination of the matrix Green’s function. Formulae for matrix elements are obtained and the behavior of Green’s functions is investigated. It is shown that the surface generated by the Green’s function has a typical sharp peak in the vicinity of the point of action of the point mass source, and in the vicinity of the top boundary of the layer ,the values of the second element of the Green’s function are times higher than the values of the first one the state of which is corresponding to the quick migration way. On this basis the solutions of the initial-boundary value problems under the action of the internal point source of mass are found. The cases of the deterministic source as well as stochastic ones under uniformand triangular distributions of the coordinate of the mass source location are considered.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2019, 23, 1; 75-99
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On a class of functional boundary value problems for the equation x'' = f(t,x,x',x'',λ)
Autorzy:
Staněk, Svatoslav
Powiązania:
https://bibliotekanauki.pl/articles/1311664.pdf
Data publikacji:
1994
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
Leray-Schauder degree theory
functional boundary conditions
boundary value problem depending on the parameter
Opis:
The Leray-Schauder degree theory is used to obtain sufficient conditions for the existence and uniqueness of solutions for the boundary value problem x'' = f(t,x,x',x'',λ), α(x) = 0, β(x̅) = 0, γ(x̿)=0, depending on the parameter λ. Here α, β, γ are linear bounded functionals defined on the Banach space of C⁰-functions on [0,1] and x̅(t) = x(0) - x(t), x̿(t)=x(1)-x(t).
Źródło:
Annales Polonici Mathematici; 1994, 59, 3; 225-237
0066-2216
Pojawia się w:
Annales Polonici Mathematici
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:
Existence results for ϕ-Laplacian Dirichlet BVP of differential inclusions with application to control theory
Autorzy:
Djebali, Smaïl
Ouahab, Abdelghani
Powiązania:
https://bibliotekanauki.pl/articles/729271.pdf
Data publikacji:
2010
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
differential inclusions
boundary value problem
fixed point
compact
convex
nonconvex
decomposable
continuous selection
controllability
Opis:
In this paper, we study ϕ-Laplacian problems for differential inclusions with Dirichlet boundary conditions. We prove the existence of solutions under both convexity and nonconvexity conditions on the multi-valued right-hand side. The nonlinearity satisfies either a Nagumo-type growth condition or an integrably boundedness one. The proofs rely on the Bonhnenblust-Karlin fixed point theorem and the Bressan-Colombo selection theorem respectively. Two applications to a problem from control theory are provided.
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2010, 30, 1; 23-49
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the Picard problem for hyperbolic differential equations in Banach spaces
Autorzy:
Sadowski, Antoni
Powiązania:
https://bibliotekanauki.pl/articles/729487.pdf
Data publikacji:
2003
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
boundary value problem
fixed point theorem
functional-integral equation
hyperbolic equation
measure of noncompactness
Opis:
B. Rzepecki in [5] examined the Darboux problem for the hyperbolic equation $z_{xy} = f(x,y,z,z_{xy})$ on the quarter-plane x ≥ 0, y ≥ 0 via a fixed point theorem of B.N. Sadovskii [6]. The aim of this paper is to study the Picard problem for the hyperbolic equation $z_{xy} = f(x,y,z,z_x,z_{xy})$ using a method developed by A. Ambrosetti [1], K. Goebel and W. Rzymowski [2] and B. Rzepecki [5].
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2003, 23, 1; 31-37
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Acoustic Impedance of a Vibrating Annular Piston Located on a Flat Rigid Baffle Around a Semi-Infinite Circular Rigid Cylinder
Autorzy:
Rdzanek, W. P.
Rdzanek, W. J.
Pieczonka, D.
Powiązania:
https://bibliotekanauki.pl/articles/176618.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Neumann boundary value problem
annular piston
acoustic impedance
semi-infinite cylindrical circular rigid baffle
Opis:
The axisymmetric problem of acoustic impedance of a vibrating annular piston embedded into a flat rigid baffle concentrically around a semi-infinite rigid cylindrical circular baffle has been undertaken in this study. The Helmholtz equation has been solved. The Green’s function valid for the zone considered has been used for this purpose. The influence of the semi-infinite cylindrical baffle on the piston’s acoustic impedance has been investigated. The acoustic impedance has been presented in both forms: integral and asymptotic, both valid for the steady harmonic vibrations. Additionally, the acoustic impedances of the piston with and without the cylindrical baffle have been compared to one another. In the case without the cylindrical baffle some earlier results have been used.
Źródło:
Archives of Acoustics; 2012, 37, 4; 411-422
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Weak solutions for nonlinear fractional differential equations with integral boundary conditions in Banach spaces
Autorzy:
Benchohra, M.
Mostefai, F.
Powiązania:
https://bibliotekanauki.pl/articles/255390.pdf
Data publikacji:
2012
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
boundary value problem
Caputo fractional derivative
measure of weak noncompactness
Pettis integrals
weak solution
Opis:
The aim of this paper is to investigate a class of boundary value problems for fractional differential equations involving nonlinear integral conditions. The main tool used in our considerations is the technique associated with measures of weak noncompactness.
Źródło:
Opuscula Mathematica; 2012, 32, 1; 31-40
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
About sign-constancy of Greens functions for impulsive second order delay equations
Autorzy:
Domoshnitsky, A.
Landsman, G.
Yanetz, S.
Powiązania:
https://bibliotekanauki.pl/articles/255963.pdf
Data publikacji:
2014
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
impulsive equations
Green's functions
positivity/negativity of Green's functions
boundary value problem
second order
Opis:
We consider the following second order differential equation with delay [formula] In this paper we find necessary and sufficient conditions of positivity of Green's functions for this impulsive equation coupled with one or two-point boundary conditions in the form of theorems about differential inequalities. By choosing the test function in these theorems, we obtain simple sufficient conditions. For example, the inequality [formula] is a basic one, implying negativity of Green's function of two-point problem for this impulsive equation in the case 0<γi≤1, 0<δi≤1 for i=1,…,p.
Źródło:
Opuscula Mathematica; 2014, 34, 2; 339-362
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of natural frequency of flexural vibrations of a single-span beam with the consideration of Timoshenko effect
Autorzy:
Jaroszewicz, J.
Łukaszewicz, K.
Powiązania:
https://bibliotekanauki.pl/articles/950070.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
beam
boundary value problem
transversal vibration
Timoshenko effect
FEM
Cauchy function
characteristic series methods
Opis:
This paper presents general solution of boundary value problem for constant cross-section Timoshenko beams with four typical boundary conditions. The authors have taken into consideration rotational inertia and shear strain by using the theory of influence by Cauchy function and characteristic series. The boundary value problem of transverse vibration has been formulated and solved. The characteristic equations considering the exact bending theory have been obtained for four cases: the clamped boundary conditions; a simply supported beam and clamped on the other side; a simply supported beam; a cantilever beam. The obtained estimators of fundamental natural frequency take into account mass and elastic characteristics of beams and Timoshenko effect. The results of calculations prove high convergence of the estimators to the exact values which were calculated by Timoshenko who used Bessel functions. Characteristic series having an alternating sign power series show good convergence. As it is shown in the paper, the error lower than 5% was obtained after taking into account only two first significant terms of the series. It was proved that neglecting the Timoshenko effect in case of short beams of rectangular section with the ratio of their length to their height equal 6 leads to the errors of calculated natural frequency: 5%÷12%.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2018, 21(3); 215-232
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Boundary Value Problems for Differential Equations with Fractional Order and Nonlinear Integral Conditions
Autorzy:
Benchohra, Mouffak
Hamani, Samira
Powiązania:
https://bibliotekanauki.pl/articles/746522.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
boundary value problem
Caputo fractional derivative
fractional integral
existence
uniqueness
fixed point
integral conditions
Opis:
In this paper, we shall establish sufficient conditions for the existence of solutions for a class of boundary value problem for fractional differential equations involving the Caputo fractional derivative and nonlinear integral conditions.
Źródło:
Commentationes Mathematicae; 2009, 49, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metoda funkcji Cauchy w analizie częstości drgań kuli sprężystej
Method of Cauchy function in analysis of radial vibration of an elastic sphere
Autorzy:
Jaroszewicz, J.
Żur, K. K.
Powiązania:
https://bibliotekanauki.pl/articles/209767.pdf
Data publikacji:
2012
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
drgania promieniowe
funkcja Cauchy'ego
zagadnienie brzegowe
radial vibrations
Cauchy function
boundary value problem
Opis:
W pracy zastosowano metodę funkcji Cauchy do rozwiązania zagadnienia brzegowego drgań promieniowych jednorodnej kuli sprężystej. Uwzględniono liniową zależność naprężenia, odkształcenia i przemieszczenia od promieniowej współrzędnej. Wyprowadzono analityczną postać szeregu charakterystycznego. Wykorzystując wzory i tablice Bernsteina-Kieropiana, obliczono częstości podstawowe i wyższe drgań promieniowych. Porównanie wyników obliczeń otrzymanych metodą funkcji wpływu z rozwiązaniem ścisłym potwierdza wysoką dokładność metody po uwzględnieniu kilku pierwszych członów szeregu charakterystycznego.
In this study, the method of Cauchy function is applied to solve boundary-value problem of free radial vibrations of an elastic isotropic sphere. The linear dependence stress, deformation and displacement against radial coordinate are settled. The form of characteristic series was derived. The application of tables and formulas of Bernstein-Kieropian to calculate basic and higher estimators of radial vibration was presented. The presented method gives satisfactory accuracy to exact solution [5] even if the characteristic series is truncated after a few first terms.
Źródło:
Biuletyn Wojskowej Akademii Technicznej; 2012, 61, 4; 115-122
1234-5865
Pojawia się w:
Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radial solutions for nonlinear elliptic equation with nonlinear nonlocal boundary conditions
Autorzy:
Kossowski, Igor
Powiązania:
https://bibliotekanauki.pl/articles/29519502.pdf
Data publikacji:
2023
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
nonlocal boundary value problem
radial solution
elliptic equation
Krasnoselskii's fixed point theorem in cone
Opis:
In this article, we prove existence of radial solutions for a nonlinear elliptic equation with nonlinear nonlocal boundary conditions. Our method is based on some fixed point theorem in a cone.
Źródło:
Opuscula Mathematica; 2023, 43, 5; 675-687
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The coincidence index for fundamentally contractible multivalued maps with nonconvex values
Autorzy:
Gabor, Dorota
Powiązania:
https://bibliotekanauki.pl/articles/1207916.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
condensing map
Fredholm operator
boundary value problem in Banach spaces
fixed point index
coincidence points
Opis:
We study a coincidence problem of the form A(x) ∈ ϕ (x), where A is a linear Fredholm operator with nonnegative index between Banach spaces and ϕ is a multivalued A-fundamentally contractible map (in particular, it is not necessarily compact). The main tool is a coincidence index, which becomes the well known Leray-Schauder fixed point index when A=id and ϕ is a compact singlevalued map. An application to boundary value problems for differential equations in Banach spaces is given.
Źródło:
Annales Polonici Mathematici; 2000, 75, 2; 143-166
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence of three solutions for impulsive multi-point boundary value problems
Autorzy:
Bohner, M.
Heidarkhani, S.
Salari, A.
Caristi, G.
Powiązania:
https://bibliotekanauki.pl/articles/255146.pdf
Data publikacji:
2017
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
multi-point boundary value problem
impulsive condition
classical solution
variational method
three critical points theorem
Opis:
This paper is devoted to the study of the existence of at least three classical solutions for a second-order multi-point boundary value problem with impulsive effects. We use variational methods for smooth functionals defined on reflexive Banach spaces in order to achieve our results. Also by presenting an example, we ensure the applicability of our results.
Źródło:
Opuscula Mathematica; 2017, 37, 3; 353-379
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Matlab implementation of direct and indirect shooting methods to solve an optimal control problem with state constraints
Autorzy:
Karbowski, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/1837359.pdf
Data publikacji:
2021
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
optimal control
numerical methods
state constraints
shooting method
multiple shooting method
boundary value problem
MATLAB
Opis:
The paper presents a general procedure to solve nume‐ rically optimal control problems with state constraints. It is used in the case, when the simple time discretization of the state equations and expressing the optimal cont‐ rol problem as a nonlinear mathematical programming problem is too coarse. It is based on using in turn two multiple shooting BVP approaches: direct and indirect. The paper is supplementary to the earlier author’s paper on direct and indirect shooting methods, presenting the theory underlying both approaches. The same example is considered here and brought to an end, that is two full listings of two MATLAB codes are shown.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2021, 15, 1; 43-50
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Peano type theorem for random fuzzy initial value problem
Autorzy:
Malinowski, Marek
Powiązania:
https://bibliotekanauki.pl/articles/729255.pdf
Data publikacji:
2011
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
Random fuzzy differential equations
random fuzzy initial value problem
fuzzy stochastic process
fuzzy random variable
Opis:
In this paper we consider the random fuzzy differential equations and show their application by an example. Under suitable conditions the Peano type theorem on existence of solutions is proved. For our purposes, a notion of ε-solution is exploited.
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2011, 31, 1; 5-22
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A verified method for solving piecewise smooth initial value problems
Autorzy:
Auer, E.
Kiel, S.
Rauh, A.
Powiązania:
https://bibliotekanauki.pl/articles/331354.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
interval method
non smooth system
initial value problem
metoda przedziałowa
metoda nie gładka
zagadnienie początkowe
Opis:
In many applications, there is a need to choose mathematical models that depend on non-smooth functions. The task of simulation becomes especially difficult if such functions appear on the right-hand side of an initial value problem. Moreover, solution processes from usual numerics are sensitive to roundoff errors so that verified analysis might be more useful if a guarantee of correctness is required or if the system model is influenced by uncertainty. In this paper, we provide a short overview of possibilities to formulate non-smooth problems and point out connections between the traditional non-smooth theory and interval analysis. Moreover, we summarize already existing verified methods for solving initial value problems with non-smooth (in fact, even not absolutely continuous) right-hand sides and propose a way of handling a certain practically relevant subclass of such systems. We implement the approach for the solver VALENCIA-IVP by introducing into it a specialized template for enclosing the first-order derivatives of non-smooth functions. We demonstrate the applicability of our technique using a mechanical system model with friction and hysteresis. We conclude the paper by giving a perspective on future research directions in this area.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2013, 23, 4; 731-747
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Qualitative methods for research of transversal vibrations of semi-infinite cable under the action of nonlinear resistance forces
Autorzy:
Pukach, P.
Kuzio, I.
Sokil, M.
Powiązania:
https://bibliotekanauki.pl/articles/411373.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Oddział w Lublinie PAN
Tematy:
mathematical model
nonlinear vibrations
nonlinear boundary value problem
Galerkin method
metod of monotony
unbounded domain
Opis:
The aim of paper is to study the solution of the problem of nonlinear transverse vibrations of elastic elongated body under the force of resistance in unbounded domain. Such problems have applications in various technical systems - vibration of pipelines, railways, long bridges, electric lines, optical fibers. Unboundedness of the area creates more fundamental difficulties in the study of the problem. For the considered models of nonlinear oscillations have no general analytical techniques for determining the dynamic characteristics of the oscillatory process. Therefore it is sugges ted to use qualitative methods of the theory of nonlinear boundary value problems to obtain correct problem solution conditions (existence and uniqueness of the solution). In the paper conditions of the correctness of the solution of mathematical model for these nonlinear systems (sufficient conditions of the existence and uniqueness in the class of locally integrable functions) are obtained. Methods of qualitative study of semi-infinite cable vibrations under the forces of resistance based on general principles of the theory of nonlinear boundary value problems - method of monotony and Galerkin method. Scientific novelty of the work lies in particular in the generalization of methods of studying nonlinear problems on a new class of oscillatory systems In unbounded domains, justifying the correctness of the solution with specified mathematical model, which has practical applications in real engineering oscillatory systems. The technique allows not only for proving the correctness of the model solution, but also has an opportunity in its study to apply various approximate methods.
Źródło:
ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes; 2013, 2, 1; 43-48
2084-5715
Pojawia się w:
ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nonlinear Heat Equation with a Fractional Laplacian in a Disk
Autorzy:
Varlamov, Vladimir
Powiązania:
https://bibliotekanauki.pl/articles/965893.pdf
Data publikacji:
1999
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
nonlinear heat equation
long-time asymptotics
fractional Laplacian
initial-boundary value problem in a disk
Opis:
For the nonlinear heat equation with a fractional Laplacian $u_t + (-Δ)^{α/2} u = u^2$, 1 < α ≤ 2, the first initial-boundary value problem in a disk is considered. Small initial conditions, homogeneous boundary conditions, and periodicity conditions in the angular coordinate are imposed. Existence and uniqueness of a global-in-time solution is proved, and the solution is constructed in the form of a series of eigenfunctions of the Laplace operator in the disk. First-order long-time asymptotics of the solution is obtained.
Źródło:
Colloquium Mathematicum; 1999, 81, 1; 101-122
0010-1354
Pojawia się w:
Colloquium Mathematicum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A generalized periodic boundary value problem for the one-dimensional p-Laplacian
Autorzy:
Jiang, Daqing
Wang, Junyu
Powiązania:
https://bibliotekanauki.pl/articles/1310724.pdf
Data publikacji:
1997
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
generalized periodic boundary value problem
p-Laplacian
upper and lower solutions
Carathéodory function
Nagumo condition
Opis:
The generalized periodic boundary value problem -[g(u')]' = f(t,u,u'), a < t < b, with u(a) = ξu(b) + c and u'(b) = ηu'(a) is studied by using the generalized method of upper and lower solutions, where ξ,η ≥ 0, a, b, c are given real numbers, $g(s) = |s|^{p-2} s$, p > 1, and f is a Carathéodory function satisfying a Nagumo condition. The problem has a solution if and only if there exists a lower solution α and an upper solution β with α(t) ≤ β(t) for a ≤ t ≤ b.
Źródło:
Annales Polonici Mathematici; 1996-1997, 65, 3; 265-270
0066-2216
Pojawia się w:
Annales Polonici Mathematici
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A singular nonlinear boundary value problem with Neumann conditions
Autorzy:
Janus, J.
Powiązania:
https://bibliotekanauki.pl/articles/255233.pdf
Data publikacji:
2005
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
singular nonlinear boundary value problem
Neumann boundary conditions
second order equations
maximal and minimal solutions
Opis:
We study the existence of solutions for the equations x" plmin g(t, x) = h(t), t mem (0, 1) with Neumann boundary conditions, where g: [0, 1] x (0, +infin) arr [0, +infin] and h: [0, 1] arr R are continuous and g(t, ·) is singular at 0 for each t mem [0, 1].
Źródło:
Opuscula Mathematica; 2005, 25, 2; 227-241
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence of solutions for a four-point boundary value problem of a nonlinear fractional differential equation
Autorzy:
Dou, X.
Li, Y.
Liu, P.
Powiązania:
https://bibliotekanauki.pl/articles/255738.pdf
Data publikacji:
2011
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
four-point boundary value problem
Riemann-Liouville fractional derivative
Green's functions
Schauder fixed point theorem
Opis:
In this paper, we discuss a four-point boundary value problem for a nonlinear differential equation of fractional order. The differential operator is the Riemann-Liouville derivative and the inhomogeneous term depends on the fractional derivative of lower order. We obtain the existence of at least one solution for the problem by using the Schauder fixed-point theorem. Our analysis relies on the reduction of the problem considered to the equivalent Fredholm integral equation.
Źródło:
Opuscula Mathematica; 2011, 31, 3; 359-372
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The general formula for calculation of fundamental frequency of axisymmetric vibrations of circular plates with linearly variable thickness
Autorzy:
Jaroszewicz, J.
Radziszewski, L.
Powiązania:
https://bibliotekanauki.pl/articles/297898.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
circular plates
variable thickness
boundary value problem
Cauchy function method
simple estimator of fundamental frequency
Opis:
This work has derived the general formula, sufficiently precise for engineering calculations of base frequency of axisymmetric free vibrations of uniform, circular diaphragm type plates clamped at the edge with linearly variable thickness. To solve the boundary problem, the Cauchy’s function method and characteristic series have been applied. The above formula has been derived on the basis of Dunkerley’s formula which is based on the first major term of the characteristic series and results in the simplest, lower bound estimator. The analysis of the formula shows that the base frequency coefficient for diaphragm plates clamped at the edge depends to only a small extent on the Poisson’s ratio, and therefore it may be averaged in the case of construction materials. Comparison of the calculations results of the simplest lower bound estimators for the base frequency obtained by using proposed method, with the results known from the literature as precise solutions, including Conway method, confirmed the high accuracy of the proposed method.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2016, 19(4); 401-410
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analytical solutions for a general mixed boundary value problem associated with motions of fluids with linear dependence of viscosity on the pressure
Autorzy:
Vieru, D.
Fetecau, C.
Bridges, C.
Powiązania:
https://bibliotekanauki.pl/articles/1839812.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
lepkość
płyn newtonowski
przepływ płynu lepkiego
analytical solutions
mixed boundary value problem
pressure dependent viscosity
Opis:
An unsteady flow of incompressible Newtonian fluids with linear dependence of viscosity on the pressure between two infinite horizontal parallel plates is analytically studied. The fluid motion is induced by the upper plate that applies an arbitrary time-dependent shear stress to the fluid. General expressions for the dimensionless velocity and shear stress fields are established using a suitable change of independent variable and the finie Hankel transform. These expressions, that satisfy all imposed initial and boundary conditions, can generate exact solutions for any motion of this type of the respective fluids. For illustration, three special cases with technical relevance are considered and some important observations and graphical representations are provided. An interesting relationship is found between the solutions corresponding to motions induced by constant or ramptype shear stresses on the boundary. Furthermore, for validation of the results, the steady-state solutions corresponding to oscillatory motions are presented in different forms whose equivalence is graphically proved.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 3; 181-197
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differential quadrature methodfor some diffusion-reaction problems
Autorzy:
Szukiewicz, Mirosław K.
Powiązania:
https://bibliotekanauki.pl/articles/184877.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
numerical algorithm
boundary value problem
reaction-diffusion equation
algorytm numeryczny
wartość graniczna
równanie dyfuzji reakcyjnej
Opis:
In the paper, differential quadrature method (DQM) is used to find numerical solutions of reaction-diffusion equations with different boundary conditions. The DQM-method changes the reaction-diffusion equation (ordinary differential equation) into a system of algebraic equations. The obtainedsystem is solved using built-in procedures of Maple®(Computer Algebra System-type program).Calculations were performed with Maple®program. The test problems include reaction-diffusionequation applied in heterogeneous catalysis. The method can be employed even in relatively hard tasks(e.g. ill-conditioned, free boundary problems).
Źródło:
Chemical and Process Engineering; 2020, 41, 1; 3-11
0208-6425
2300-1925
Pojawia się w:
Chemical and Process Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the existence for the Cauchy-Neumann problem for the Stokes system in the $L_p$-framework
Autorzy:
Mucha, Piotr
Zajączkowski, Wojciech
Powiązania:
https://bibliotekanauki.pl/articles/1205939.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
Stokes system
Marcinkiewicz theorem
Cauchy-Neumann initial boundary value problem
the Fourier transform
existence of solutions
Opis:
The existence for the Cauchy-Neumann problem for the Stokes system in a bounded domain $Ω ⊂ ℝ^3$ is proved in a class such that the velocity belongs to $W^{2,1}_r (Ω × (0,T))$, where r > 3. The proof is divided into three steps. First, the existence of solutions is proved in a half-space for vanishing initial data by applying the Marcinkiewicz multiplier theorem. Next, we prove the existence of weak solutions in a bounded domain and then we regularize them. Finally, the problem with nonvanishing initial data is considered.
Źródło:
Studia Mathematica; 2000, 143, 1; 75-101
0039-3223
Pojawia się w:
Studia Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Energy integral of the Stokes flow in a singularly perturbed exterior domain
Autorzy:
Riva, M. D.
Powiązania:
https://bibliotekanauki.pl/articles/255971.pdf
Data publikacji:
2012
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
boundary value problem for Stokes system
singularly perturbed exterior domain
real analytic continuation in Banach space
Opis:
We consider a pair of domains Ωb and Ωs in Rn and we assume that the closure of Ωb does not intersect the closure of ε Ωs for ε ∈ (0, ε 0). Then for a fixed ε ∈ (0, ε0)we consider a boundary value problem in Rn\ (Ωb ∪ εΩs) which describes the steady state Stokes flow of an incompressible viscous fluid past a body occupying the domain Ωb and past a small impurity occupying the ε Ωs. The unknown of the problem are the velocity field u and the pressure field p, and we impose the value of the velocity field u on the boundary both of the body and of the impurity. We assume that the boundary velocity on the impurity displays an arbitrarily strong singularity when ε tends to 0. The goal is to understand the behaviour of the strain energy of (u, p) for ε small and positive. The methods developed aim at representing the limiting behaviour in terms of analytic maps and possibly singular but completely known functions of ε, such as ε-1, log &epsilon.
Źródło:
Opuscula Mathematica; 2012, 32, 4; 647-659
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Local existence of solutions of the mixed problem for the system of equations of ideal relativistic hydrodynamics
Autorzy:
Rencławowicz, Joanna
Zajączkowski, Wojciech
Powiązania:
https://bibliotekanauki.pl/articles/1339037.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
relativistic hydrodynamics
symmetrization
existence
system of hyperbolic equations of the first order
initial-boundary value problem
Opis:
Existence and uniqueness of local solutions for the initial-boundary value problem for the equations of an ideal relativistic fluid are proved. Both barotropic and nonbarotropic motions are considered. Existence for the linearized problem is shown by transforming the equations to a symmetric system and showing the existence of weak solutions; next, the appropriate regularity is obtained by applying Friedrich's mollifiers technique. Finally, existence for the nonlinear problem is proved by the method of successive approximations.
Źródło:
Applicationes Mathematicae; 1998-1999, 25, 2; 221-252
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sound Radiation from a Surface Source Located at the Bottom of the Wedge Region
Autorzy:
Szemela, K.
Powiązania:
https://bibliotekanauki.pl/articles/176912.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
wedge region
sound pressure
sound power
Neumann boundary value problem
Helmholtz equation
vibrating piston
Hankel transform
Opis:
Applying rigorous analytical methods, formulas describing the sound radiation have been obtained for the wedge region bounded by two transverse baffles with a common edge and bottom. It has been assumed that the surface sound source is located at the bottom. The presented formulas can be used to calculate the sound pressure and power inside the wedge region. They are valid for any value of the wedge angle and represent a generalization of the formulas describing the sound radiation inside the two and three-wall corner region. Moreover, the presented formulas can be easily adapted for any case when more than one sound source is located at the bottom. To demonstrate their practical application, the distribution of the sound pressure modulus and the sound power have been analyzed in the case of a rectangular piston located at the wedge’s bottom. The influence of the transverse baffle on the sound power has been investigated. Based on the obtained formulas, the behaviour of acoustic fields inside a wedge can be predicted.
Źródło:
Archives of Acoustics; 2015, 40, 2; 223-234
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A mixed type boundary-value problem related to the electrostatics of cold plasma jet reactors based on dielectric barrier discharge
Autorzy:
Vafeas, Panayiotis
Papadopoulos, Polycarpos K.
Svarnas, Panagiotis
Powiązania:
https://bibliotekanauki.pl/articles/1838214.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
DBD
dielectric barrier discharge
cold plasma jet
reactor
mixed type boundary value problem
electrostatic potential theory
Opis:
A semi-analytical model is presented for the determination of the electric field in reactors used for cold atmospheric pressure plasma (CAPP) jet production, based on the concept of dielectric barrier discharge (DBD). These systems are associated with various applications in contemporary engineering, ranging from material processing to biomedicine, and at the same time they provide many challenges for fundamental research. Here, we consider a simplified system configuration of a single driven electrode, surrounding a thin dielectric tube, which does not contribute to the electric field, since the potential variation is immediate due to its negligible size. By employing the cylindrical coordinate system that perfectly fits the present plasma jet reactor, we separate the area of electric activity into three distinct domains according to the imposed external conditions, while our analysis is restricted to the electrostatic limit of Maxwell’s equations. To this end, cylindrical harmonic field expansions are used for the potential, which produce the corresponding electric fields in each subdomain. Due to the imposed mixed-type boundary value problem, additional linear terms are incorporated, leading to three possible analytical solutions of the physical problem under consideration. The efficiency of the method is demonstrated by comparing the final formulae with a numerical solution, followed by the relevant discussion.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2021, 31, 2; 233-245
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The finite difference method on adaptive mesh for singularly perturbed nonlinear 1D reaction diffusion boundary value problems
Autorzy:
Duru, Hakkı
Güneş, Baransel
Powiązania:
https://bibliotekanauki.pl/articles/1839738.pdf
Data publikacji:
2020
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
boundary value problem
singularly perturbed problem
finite difference method
metoda różnic skończonych
schemat różnicowy
metoda Newtona-Raphsona
równanie reakcji–dyfuzji
Opis:
In this paper, we study singularly perturbed nonlinear reaction-diffusion equations. The asymptotic behavior of the solution is examined. The difference scheme which is accomplished by the method of integral identities with using of interpolation quadrature rules with weight functions and remainder term integral form is established on adaptive mesh. Uniform convergence and stability of the difference method are discussed in the discrete maximum norm. The discrete scheme shows that orders of convergent rates are close to 2. An algorithm is presented, and some problems are solved to validate the theoretical results.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2020, 19, 4; 45-56
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The finite difference method on adaptive mesh for singularly perturbed nonlinear 1D reaction diffusion boundary value problems
Autorzy:
Duru, Hakkı
Güneş, Baransel
Powiązania:
https://bibliotekanauki.pl/articles/1839748.pdf
Data publikacji:
2020
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
boundary value problem
singularly perturbed problem
finite difference method
metoda różnic skończonych
schemat różnicowy
metoda Newtona-Raphsona
równanie reakcji–dyfuzji
Opis:
In this paper, we study singularly perturbed nonlinear reaction-diffusion equations. The asymptotic behavior of the solution is examined. The difference scheme which is accomplished by the method of integral identities with using of interpolation quadrature rules with weight functions and remainder term integral form is established on adaptive mesh. Uniform convergence and stability of the difference method are discussed in the discrete maximum norm. The discrete scheme shows that orders of convergent rates are close to 2. An algorithm is presented, and some problems are solved to validate the theoretical results.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2020, 19, 4; 45-56
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fractional boundary value problems on the half line
Autorzy:
Frioui, A.
Guezane-Lakoud, A.
Khaldi, R.
Powiązania:
https://bibliotekanauki.pl/articles/255663.pdf
Data publikacji:
2017
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
boundary value problem at resonance
existence of solution
unbounded interval
coincidence degree of Mawhin
fractional differential equation
Opis:
In this paper, we focus on the solvability of a fractional boundary value problem at resonance on an unbounded interval. By constructing suitable operators, we establish an existence theorem upon the coincidence degree theory of Mawhin. The obtained results are illustrated by an example.
Źródło:
Opuscula Mathematica; 2017, 37, 2; 265-280
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Solution of fractional heat-like and fractional wave-like equation by using modern strategy
Autorzy:
Mohamed, Zain El Abden
Hamza, Amjad
Elzaki, Tarig
Algolam, Mohamed
Elhussein, Shiraz
Powiązania:
https://bibliotekanauki.pl/articles/2233715.pdf
Data publikacji:
2023
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
fractional-order wave-like equation
fractional-order heat-like equation
initial-boundary value problem
Adomian decomposition method
Opis:
This paper introduces a novel form of the Adomian decomposition (ADM) method for solving fractional-order heat-like and wave-like equations with starting and boundary value problems. The derivations are provided in the sense of Caputo. In order to help understanding, the generalised formulation of the current approach is provided. Several numerical examples of fractional-order diffusion-wave equations (FDWEs) are solved using the suggested method in this context. In addition to examining the applicability of the suggested method to the solving of fractional-order heat-like and wave-like equations, a graphical depiction of the solutions to three instructive cases was constructed. Solution graphs were arrived at for integer and fractional-order problems. The derived and exact solutions to integer-order problems were found to be in excellent agreement. The subject of the present research endeavour is the convergence of fractional-order solutions. This strategy is considered to be the most successful way of addressing fractional-order initial-boundary value issues in science and engineering. This strategy is presented here.
Źródło:
Acta Mechanica et Automatica; 2023, 17, 3; 372--380
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Solution of the boundary value problem of heat conduction in a cone
Autorzy:
Ramazanov, Murat
Jenaliyev, Muvasharkhan
Gulmanov, Nurtay
Powiązania:
https://bibliotekanauki.pl/articles/2048719.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
non-cylindrical domain
cone
boundary value problem of heat conduction
singular Volterra integral equation
Carleman–Vekua regularization method
Opis:
In the paper we consider the boundary value problem of heat conduction in a non-cylindrical domain, which is an inverted cone, i.e. in the domain degenerating into a point at the initial moment of time. In this case, the boundary conditions contain a derivative with respect to the time variable; in practice, problems of this kind arise in the presence of the condition of the concentrated heat capacity. We prove a theorem on the solvability of a boundary value problem in weighted spaces of essentially bounded functions. The issues of solvability of the singular Volterra integral equation of the second kind, to which the original problem is reduced, are studied. We use the Carleman–Vekua method of equivalent regularization to solve the obtained singular Volterra integral equation.
Źródło:
Opuscula Mathematica; 2022, 42, 1; 75-91
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Long-time asymptotics for the nonlinear heat equation with a fractional Laplacian in a ball
Autorzy:
Varlamov, Vladimir
Powiązania:
https://bibliotekanauki.pl/articles/1206006.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
first initial-boundary value problem
nonlinear heat equation
construction of solutions
higher-order long-time asymptotics
fractional Laplacian
Opis:
The nonlinear heat equation with a fractional Laplacian $[u_t+(-Δ)^{α/2} u = u^2, 0 < α ≤ 2]$, is considered in a unit ball $B$. Homogeneous boundary conditions and small initial conditions are examined. For 3/2 + ε₁ ≤ α ≤ 2, where ε₁ > 0 is small, the global-in-time mild solution from the space $C⁰([0,∞), H₀^{κ}(B))$ with κ < α - 1/2 is constructed in the form of an eigenfunction expansion series. The uniqueness is proved for 0 < κ < α - 1/2, and the higher-order long-time asymptotics is calculated.
Źródło:
Studia Mathematica; 2000, 142, 1; 71-99
0039-3223
Pojawia się w:
Studia Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Entropy generation minimization in transient heat conduction processes PART II – Transient heat conduction in solids
Autorzy:
Kolenda, Z. S.
Szmyd, J. S.
Powiązania:
https://bibliotekanauki.pl/articles/201936.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
transient heat conduction
initial boundary value problem
entropy generation minimization
przewodzenia ciepła
początkowa wartość graniczna
minimalizacja entropii generacji
Opis:
Formulation and solution of the initial boundary-value problem of heat conduction in solids have been presented when an entropy generation minimization principle is imposed as the arbitrary constraint. Using an entropy balance equation and the Euler-Lagrange variational approach a new form of the heat conduction equation (non-linear partial difference equation) is derived.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2014, 62, 4; 883-887
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of additional mass rings on frequencies of axi-symmetrical vibrations of clamped circular plates of linearly variable thickness
Wpływ dodatkowych pierścieni masowych na częstości drgań osiowosymetrycznych płyty o liniowo-zmiennej grubości utwierdzonej na obwodzie
Autorzy:
Jaroszewicz, J.
Zoryj, L.
Katunin, A.
Powiązania:
https://bibliotekanauki.pl/articles/280678.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
płyty o grubości liniowo-zmiennej
drgania osiowosymetryczne
masa pierścieniowa
circular plates
variable thickness
boundary value problem
partial discretization method
Opis:
The aim of this paper is to analyze the influence of values and radius of an additional mass ring on the continuous distribution of mass of a clamped circular plate of linearly variable thickness. The linear theory of thin plates is used for description of small buckling vibrations. The authors applied the partial discretization method which is based on the discretization of the continuous mass and continuous buckling rigidity function. It is also based on the method of Cauchy's influence function, which gives particularly exact effects for distributed-continuous systems such as that presented in this paper. It is shown that an approximate result leads to the exact value with the discretization degree of less than~5, and it is not dependent on the value and radius of the concentrated mass. Exact results of calculations lead to accurate values discovered by Conway for plates of linearly variable thickness without an additional mass and to accurate values discovered by Roberson for plates of constant thickness with the mass concentrated in the center.
W pracy zbadano wpływ wartości i promienia dodatkowej masy pierścieniowej występującej w ciągłym rozkładzie masy płyty o liniowo-zmiennej grubości. Pominięto przy tym wpływ pierścienia masowego na sztywność giętną płyty. Zastosowano liniową teorię cienkich płyt do opisu małych drgań giętnych. Zastosowana metoda dyskretyzacji polega na dyskretyzacji masy ciągłej płyty i pozostawieniu ciągłej funkcji sztywności. Bazuje ona na metodzie funkcji wpływu Cauchy'ego, która daje szczególnie dobre efekty dla układów dyskretno-ciągłych. Pokazano, że rozwiązanie przybliżone zbiega do wartości ścisłej już przy stopniu dyskretyzacji mniejszym niż 5, niezależnie od wartości i promienia rozłożenia masy skupionej. Uzyskane wyniki obliczeń zmierzają do ścisłych wartości uzyskanych przez Conway'a dla płyty o liniowo-zmiennej grubości bez dodatkowej masy i do wyników Robersona dla płyty o stałej grubości z dodatkową masą skupioną w środku symetrii.
Źródło:
Journal of Theoretical and Applied Mechanics; 2006, 44, 4; 867-880
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the use of Mohand integral transform for solving fractional-order classical Caputo differential equations
Autorzy:
Qureshi, Sania
Yusuf, Abdullahi
Aziz, Shaheen
Powiązania:
https://bibliotekanauki.pl/articles/1839755.pdf
Data publikacji:
2020
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
initial value problem
kinetic reaction
Riemann-Liouville integral
transformata całkowa Mohanda
całka Mohanda
całka Riemanna-Liouville'a
reakcja kinetyczna
Opis:
In this research study, a newly devised integral transform called the Mohand transform has been used to find the exact solutions of fractional-order ordinary differential equations under the Caputo type operator. This transform technique has successfully been employed in existing literature to solve classical ordinary differential equations. Here, a few significant and practically-used differential equations of the fractional type, particularly related with kinetic reactions from chemical engineering, are under consideration for the possible outcomes via the Mohand integral transform. A new theorem has been proposed whose proof, provided in the present study, helped to get the exact solutions of the models under investigation. Upon comparison, the obtained results would agree with results produced by other existing well-known integral transforms including Laplace, Fourier, Mellin, Natural, Sumudu, Elzaki, Shehu and Aboodh.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2020, 19, 3; 99-109
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of Energy Slope Averaging Methods on Numerical Solution of 1D Steady Gradually Varied Flow
Autorzy:
Artichowicz, W.
Prybytak, D.
Powiązania:
https://bibliotekanauki.pl/articles/240952.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
standard step method
numerical integration
initial-value problem
ordinary differential equation
open channel
steady gradually varied flow
energy slope
Opis:
In this paper, energy slope averaging in the one-dimensional steady gradually varied flow model is considered. For this purpose, different methods of averaging the energy slope between cross-sections are used. The most popular are arithmetic, geometric, harmonic and hydraulic means. However, from the formal viewpoint, the application of different averaging formulas results in different numerical integration formulas. This study examines the basic properties of numerical methods resulting from different types of averaging.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2015, 62, 3-4; 101-119
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Nonlinear Differential Equations in Generalized Musielak-Orlicz Spaces
Autorzy:
Kozlowski, W.M.
Powiązania:
https://bibliotekanauki.pl/articles/744903.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
ordinary differential equation, nonlinear equation, Cauchy problem, initial value problem, fixed point, nonexpansive mapping, modular function space, Orlicz space, Musielak-Orlicz space, convex modular
Opis:
We consider ordinary differential equations \(u'(t)+(I-T)u(t)=0\), where an unknown function takes its values in a given modular function space being a generalization of Musielak-Orlicz spaces, and \(T\) is nonlinear mapping which is nonexpansive in the modular sense. We demonstrate that under certain natural assumptions the Cauchy problem related to this equation can be solved. We also show a process for the construction of such a solution. This result is then linked to the recent results of the fixed point theory in modular function spaces.
Źródło:
Commentationes Mathematicae; 2013, 53, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The evolution of linearized perturbations in a magnetohydrodynamic boundary layer
Autorzy:
Vijayalakshmi, A. R.
Balagondar, P. M.
Powiązania:
https://bibliotekanauki.pl/articles/955146.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
magnetohydrodynamika
transformacja Fouriera
warstwa graniczna
pole magnatyczne
magnetohydrodynamic boundary layer
initial-value problem approach
Alfv’n velocity
Fourire transform technique
Opis:
The evolution of linearized perturbations in a magnetohydrodynamic shear flow is studied using the initial value problem approach. Here the resulting equation in time posed by using the Fourier transform is solved for the Fourier amplitudes for modeled boundary layer for different initial disturbances. The shear flow prototype here is a piecewise linear approximation of a magnetohydrodynamic boundary layer. The initial disturbances that are considered are a point source of the field of transverse velocity and magnetic field. Solutions are obtained for small values of Alfve’n velocity. The velocity plots are drawn for different values of Alfve’n velocity.
Źródło:
International Journal of Applied Mechanics and Engineering; 2014, 19, 2; 397-406
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Existence and uniqueness of solutions for nonlinear Katugampola fractional differential equations
Autorzy:
Basti, Bilal
Arioua, Yacine
Benhamidouche, Nouredine
Powiązania:
https://bibliotekanauki.pl/articles/357816.pdf
Data publikacji:
2019
Wydawca:
Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
Tematy:
fractional equations
fixed point theorems
boundary value problem
existence
uniqueness
równanie ułamkowe
twierdzenie o punkcie stałym
zagadnienie brzegowe
istnienie
wyjątkowość
Opis:
The present paper deals with the existence and uniqueness of solutions for a boundary value problem of nonlinear fractional differential equations with Katugampola fractional derivative. The main results are proved by means of Guo-Krasnoselskii and Banach fixed point theorems. For applications purposes, some examples are provided to demonstrate the usefulness of our main results.
Źródło:
Journal of Mathematics and Applications; 2019, 42; 35-61
1733-6775
2300-9926
Pojawia się w:
Journal of Mathematics and Applications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Limitation of Cauchy Function Method in Analysis of Estimators of Frequency and Form of Natural Vibrations of Circular Plate with Variable Thickness and Clamped Edges
Autorzy:
Jaroszewicz, J.
Żur, K.
Powiązania:
https://bibliotekanauki.pl/articles/387099.pdf
Data publikacji:
2012
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
drgania
model płaskiej struktury
zagadnienia brzegowe
estymatory Bernsteina-Kieropiana
vibration
circular plate
boundary value problem
Cauchy function
Bernstein-Kieropian’s estimators
Opis:
In this paper the Berstein-Kieropian double estimators of basic natural frequency of circular plate with power variable thickness along the radius and clamped edges in diaphragm form were analyzed in a theoretical approach. The approximate solution of boundary problem of transversal vibration by means of Cauchy function and characteristic series method has been applied for chosen values of power indicator of variable thickness and material Poisson’s ratio has been chosen which led to exact form solutions. Particular attention has been given to a singularity arising from the uncertainty of estimates of Bernstein-Kieropian. Improving this method has been obtained the general form of Cauchy function for arbitrary values of and , which are physically justified. Therefore, the aim of the paper was to explore the reason why for a plate above a certain value = 3.97 exact solution, which Conway couldn’t receive (Conway, 1958a, b)
Źródło:
Acta Mechanica et Automatica; 2012, 6, 2; 53-57
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł

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