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Infinitely many solutions of a second-order p -Laplacian problem with impulsive condition

Libo Wang, Weigao Ge, Minghe Pei (2010)

Applications of Mathematics

Using the critical point theory and the method of lower and upper solutions, we present a new approach to obtain the existence of solutions to a p -Laplacian impulsive problem. As applications, we get unbounded sequences of solutions and sequences of arbitrarily small positive solutions of the p -Laplacian impulsive problem.

Influence of time delays on the Hahnfeldt et al. angiogenesis model dynamics

Marek Bodnar, Urszula Foryś (2009)

Applicationes Mathematicae

We study the influence of time delays on the dynamics of the general Hahnfeldt et al. model of an angiogenesis process. We analyse the dynamics of the system for different values of the parameter α which reflects the strength of stimulation of the vessel formation process. Time delays are introduced in three subprocesses: tumour growth, stimulation and inhibition of vessel formation (represented by endothelial cell dynamics). We focus on possible destabilisation of the positive steady state due...

Influence of Vibrations on Convective Instability of Reaction Fronts in Liquids

K. Allali, F. Bikany, A. Taik, V. Volpert (2010)

Mathematical Modelling of Natural Phenomena

Propagation of polymerization fronts with liquid monomer and liquid polymer is considered and the influence of vibrations on critical conditions of convective instability is studied. The model includes the heat equation, the equation for the concentration and the Navier-Stokes equations considered under the Boussinesq approximation. Linear stability analysis of the problem is fulfilled, and the convective instability boundary is found depending on...

Initial boundary value problem for the mKdV equation on a finite interval

Anne Boutet de Monvel, Dmitry Shepelsky (2004)

Annales de l’institut Fourier

We analyse an initial-boundary value problem for the mKdV equation on a finite interval ( 0 , L ) by expressing the solution in terms of the solution of an associated matrix Riemann-Hilbert problem in the complex k -plane. This RH problem is determined by certain spectral functions which are defined in terms of the initial-boundary values at t = 0 and x = 0 , L . We show that the spectral functions satisfy an algebraic “global relation” which express the implicit relation between all boundary values in terms of spectral...

Input-output systems in Biology and Chemistry and a class of mathematical models describing them

Erich Bohl, Ivo Marek (2005)

Applications of Mathematics

Our aim is to show a class of mathematical models in application to some problems of cell biology. Typically, our models are described via classical chemical networks. This property is visualized by a conservation law. Mathematically, this conservation law guarantees most of the mathematical properties of the models such as global existence and uniqueness of solutions as well as positivity of the solutions for positive data. These properties are consequences of the fact that the infinitesimal generators...

Input-to-state stability of neutral type systems

Michael I. Gil' (2013)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

We consider the system ( t ) - η d R ̃ ( τ ) ( t - τ ) = 0 η d R ( τ ) x ( t - τ ) + [ F x ] ( t ) + u ( t ) (ẋ(t) ≡ dx(t)/dt), where x(t) is the state, u(t) is the input, R(τ),R̃(τ) are matrix-valued functions, and F is a causal (Volterra) mapping. Such equations enable us to consider various classes of systems from the unified point of view. Explicit input-to-state stability conditions in terms of the L²-norm are derived. Our main tool is the norm estimates for the matrix resolvents, as well as estimates for fundamental solutions of the linear parts of the considered systems,...

Currently displaying 61 – 80 of 199