PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 11

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  równanie hiperboliczne
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available Approximate state-space and transfer function models for 2x2 linear hyperbolic systems with collocated boundary inputs
Bartecki Krzysztof
International Journal of Applied Mathematics and Computer Science
|
2020
|
Vol. 30, no. 3
475--491
EN
Two approximate representations are proposed for distributed parameter systems described by two linear hyperbolic PDEs with two time- and space-dependent state variables and two collocated boundary inputs. Using the method of lines with the backward difference scheme, the original PDEs are transformed into a set of ODEs and expressed in the form of a finite number of dynamical subsystems (sections). Each section of the approximation model is described by state-space equations with matrix-valued state, input and output operators, or, equivalently, by a rational transfer function matrix. The cascade interconnection of a number of sections results in the overall approximation model expressed in finite-dimensional state-space or rational transfer function domains, respectively. The discussion is illustrated with a practical example of a parallel-flow double-pipe heat exchanger. Its steady-state, frequency and impulse responses obtained from the original infinite-dimensional representation are compared with those resulting from its approximate models of different orders. The results show better approximation quality for the “crossover” input–output channels where the in-domain effects prevail as compared with the “straightforward” channels, where the time-delay phenomena are dominating.
2
Content available Extended models of sedimentation in coastal zone
Selezov I.
Vibrations in Physical Systems
|
2014
|
Vol. 26
243--250
EN
Construction of a generalized hyperbolic model of sediment dynamics predicting a sediment evolution on the bottom surface with a finite velocity is presented. The transport equation is extended with introducing a generalized operator of flux change and a generalized operator of gradient. Passing to the convenient model is a singular degeneration of extended model. In this case the results are obtained in the class of generalization solutions. Some expressive examples of constructions of hyperbolic models predicting a finite velocity of disturbance propagation are presented. This problem is developed starting from Maxwell (1861). His approach in the theory of electromagnetism and the kinetic theory of gases is commented. A brief review on propagation of heat and diffusive waves is presented. The similar problems in the theory of probability and diffusion waves are considered. In particular, it was shown on the microscopic level for metals that the conservation law can be violated.
3
Content available remote The existence of a unique solution of the hyperbolic functional differential equation
Karpowicz A.
Demonstratio Mathematica
|
2014
|
Vol. 47, nr 4
866--877
EN
We consider the Z. Szmydt problem for the hyperbolic functional differential equation. We prove a theorem on existence of a unique classical solution and the Carathéodory solution of the hyperbolic equation.
4
Content available remote Solution of 2D hyperbolic equation by means of the BEM using discretization in time
Drozdek J., Lupa M., Ładyga E.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
|
2009
|
Vol. 8, nr 1
19-24
EN
The hyperbolic equation (2D problem) supplemented by adequate boundary and initial conditions is considered. To solve the problem the boundary element method using discretization in time is adapted. In the final part of the paper the example of computations is shown.
5
Content available remote Solution of 2D hyperbolic equation by means of the BEM using discretization in time - analysis of solution exactness
Drozdek J., Lupa M., Ładyga E.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
|
2009
|
Vol. 8, nr 1
25-32
EN
The hyperbolic equation (2D problem) supplemented by adequate boundary and initial conditions is considered. This equation is solved by means of the boundary element method using discretization in time. The aim of investigations is to analyze the influence of time step and the discretization assumed on the exactness of the obtained results.
6
Further results on oscillation of hyperbolic differential equations of neutral type
Wang M., Wang P. G., Ge W.
Journal of Applied Analysis
|
2004
|
Vol. 10, nr 1
117-129
EN
In this paper, we investigate a class of hyperbolic differential equations of neutral type [wzór] (E) and obtain some new sufficient conditions of the oscillation for such equations satisfying boundary condition [wzór] (B)
7
Content available remote The Stability of an Irrigation Canal System
Bounit H.
International Journal of Applied Mathematics and Computer Science
|
2003
|
Vol. 13, no 4
453-468
EN
In this paper we examine the stability of an irrigation canal system. The system considered is a single reach of an irrigation canal which is derived from Saint-Venant's equations. It is modelled as a system of nonlinear partial differential equations which is then linearized. The linearized system consists of hyperbolic partial differential equations. Both the control and observation operators are unbounded but admissible. From the theory of symmetric hyperbolic systems, we derive the exponential (or internal) stability of the semigroup underlying the system. Next, we compute explicitly the transfer functions of the system and we show that the input-output (or external) stability holds. Finally, we prove that the system is regular in the sense of (Weiss, 1994) and give various properties related to its transfer functions.
8
Two-waves nonlinear interactions for hyperbolic systems of balance laws
Barbera E., Giambo S.
Journal of Technical Physics
|
2002
|
Vol. 43, no 2
165-185
EN
In this paper we study the weakly nonlinear interaction of two waves whose propagation is governed by hyperbolic systems of balance laws. The method used here makes use of nonlinear phase variables and consists in a perturbation analysis. It is applied to an Eulerian gas and to a gas described by extended thermodynamics with thirteen moments.
9
O pewnym mechanizmie silnych zaburzeń
Flyud V., Tsymbal V.
Zeszyty Naukowe. Matematyka / Politechnika Opolska
|
2001
|
z. 17
31-39
PL
W niniejszym artykule skonstruowano asymptotykę silnie zaburzonego granicznego zagadnienia dla równania hiperbolicznego. Rozważamy przypadek zdegenerowania równania hiperbolicznego w hiperboliczne.
10
Content available remote On the tempered distribution related to the ultra-hyperbolic equations
Kananthai A.
Fasciculi Mathematici
|
1999
|
Nr 29
35-42
EN
In this paper, the distribution[...], where a is a complex number, [...] is the n-dimensional ultra-hyperbolic operator iterated k-times, is considered. Some properties of eat D k t5 are studied. Moreover, eat D k t5 is used to solving of the equation of the ultra-hyperbolic type.
11
Content available remote On the existence of weak solutions of the Darboux problem for the hyperbolic partial differential equations in Banach spaces
Kubiaczyk I., Mostafa Ali N.
Fasciculi Mathematici
|
1998
|
Nr 28
93-99
EN
In this paper we prove an existence theorem for the hyperbolic partial differential equation zx.y = f(x,y,z,zxy), z(x,O)=o, z(O,y)=O for x,y>O, where Zxy means the second mixed derivative in the weak sence. The continuity of the xy function f is replaced by the weak continuity and the compactness condition is expressed in ternls of the measuresa of weak noncompactness. This paper extends some previous results for our equation.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.