Displaying 21 – 40 of 584

Showing per page

A periodic boundary value problem in Hilbert space

Boris Rudolf (1994)

Mathematica Bohemica

In the paper some existence results for periodic boundary value problems for the ordinary differential equation of the second order in a Hilbert space are given. Under some auxiliary assumptions the set of solutions is compact and connected or it is convex.

A Periodic Lotka-Volterra System

Tsvetkov, D. (1996)

Serdica Mathematical Journal

In this paper periodic time-dependent Lotka-Volterra systems are considered. It is shown that such a system has positive periodic solutions. It is done without constructive conditions over the period and the parameters.

A periodic model for the dynamics of cell volume

Philip Korman (2016)

Annales Polonici Mathematici

We prove the existence and uniqueness of a positive periodic solution for a model describing the dynamics of cell volume flux, introduced by Julio A. Hernández [Bull. Math. Biol. 69 (2007), 1631-1648]. We also show that the periodic solution is a global attractor. Our results confirm the conjectures made in an interesting recent book of P. J. Torres [Atlantis Press, 2015].

A predator-prey model with state dependent impulsive effects

Changming Ding (2014)

Annales Polonici Mathematici

We investigate a Lotka-Volterra predator-prey model with state dependent impulsive effects, in which the control strategies by releasing natural enemies and spraying pesticide at different thresholds are considered. We present some sufficient conditions to guarantee the existence and asymptotical stability of semi-trivial periodic solutions and positive periodic solutions.

A simple model of thermoelectric oscillations

Giovanni Cimatti, Eduard Feireisl (1995)

Applications of Mathematics

A system of ordinary differential equations modelling an electric circuit with a thermistor is considered. Qualitative properties of solution are studied, in particular, the existence and nonexistence of time-periodic solutions (the Hopf bifurcation).

A tight bound of modified iterative hard thresholding algorithm for compressed sensing

Jinyao Ma, Haibin Zhang, Shanshan Yang, Jiaojiao Jiang (2023)

Applications of Mathematics

We provide a theoretical study of the iterative hard thresholding with partially known support set (IHT-PKS) algorithm when used to solve the compressed sensing recovery problem. Recent work has shown that IHT-PKS performs better than the traditional IHT in reconstructing sparse or compressible signals. However, less work has been done on analyzing the performance guarantees of IHT-PKS. In this paper, we improve the current RIP-based bound of IHT-PKS algorithm from δ 3 s - 2 k < 1 32 0 . 1768 to δ 3 s - 2 k < 5 - 1 4 0 . 309 , where δ 3 s - 2 k is the restricted...

A Tikhonov-type theorem for abstract parabolic differential inclusions in Banach spaces

Anastasie Gudovich, Mikhail Kamenski, Paolo Nistri (2001)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

We consider a class of singularly perturbed systems of semilinear parabolic differential inclusions in infinite dimensional spaces. For such a class we prove a Tikhonov-type theorem for a suitably defined subset of the set of all solutions for ε ≥ 0, where ε is the perturbation parameter. Specifically, assuming the existence of a Lipschitz selector of the involved multivalued maps we can define a nonempty subset Z L ( ε ) of the solution set of the singularly perturbed system. This subset is the set of...

Currently displaying 21 – 40 of 584