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NONLINEAR ANALYSIS


Vol. 37, No. 2           June 2011


TABLE OF CONTENTS


Title and Author(s) Page
item Multiple solitary wave solutions of nonlinear Schrodinger systems
Rushun Tian and Zhi-Qiang Wang
ABSTRACT. Consider the $N$-coupled nonlinear elliptic system
\cases \displaystyle -\Delta U_j+ U_j=\mu U_j^3+\beta U_j\sum_{k\neq j} U_k^2 \quad \text{in } \Omega,
U_j>0 \quad\text{in } \Omega,\quad U_j=0 \quad \text{on } \partial\Omega,\ j=1, \ldots, N. \endcases \tag P
where $\Omega$ is a smooth and bounded (or unbounded if $\Omega$ is radially symmetric) domain in $\R^n$, $n\leq3$. By using a $Z_N$ index theory, we prove the existence of multiple solutions of (P) and show the dependence of multiplicity results on the coupling constant $\beta$.
203
item Eight positive periodic solutions to tree species non-autonomous Lotka-Volterra cooperative systems with harvesting terms
Yongkun Li and Kaihong Zhao
ABSTRACT. By using Mawhin's continuation theorem of coincidence degree theory and linear inequality, we establish the existence of eight positive periodic solutions for three species non-autonomous Lotka-Volterra cooperative systems with harvesting terms. An example is given to illustrate the effectiveness of our results.
225
item Existence of periodic solutions for $p$-Laplacian neutral functional equation with multiple deviating arguments
Tian Xiang and Rong Yuan
ABSTRACT. By using the theory of coincidence degree and some refined analysis techniques, we study a general kind of periodic solutions to $p$-Laplacian neutral functional differential equation with multiple deviating arguments. A general analysis method to tackle with such equations is formed. Some new and universal results on the existence of periodic solutions are obtained, meanwhile, some known results in the literatures are improved. An example is provided as an application to our theorems.
235
item Forced oscillations in strongly damped beam equation
Aleksander Cwiszewski
ABSTRACT. It is proved that the extensible beam equation in Ball's model admits periodic solutions near equilibrium states if subject to external periodic force of high frequency. The approach is based on translation along trajectories, averaging method and homotopy invariants such as topological degree and fixed point index.
259
item Unbounded connected component of the positive solutions set of some semi-positone problems
Xu Xian and Sun Jingxian
ABSTRACT. In this paper, first we obtain some results for structure of positive solutions set of some nonlinear operator equation. Then using these results, we obtain some existence results for positive solutions of the nonlinear operator equation. The method to show our main results is the global bifurcation theory.
283
item On second-order boundary value problems in Banach spaces: a bound sets approach
Jan Andres, Luisa Malaguti and Martina Pavlackova
ABSTRACT. The existence and localization of strong (Carath\'{e}odory) solutions is obtained for a second-order Floquet problem in a Banach space. The combination of applied degree arguments and bounding (Liapunov-like) functions allows some solutions to escape from a given set. The problems concern both semilinear differential equations and inclusions. The main theorem for upper-Carath\'{e}odory inclusions is separately improved for Marchaud inclusions (i.e. for globally upper semicontinuous right-hand sides) in the form of corollary. Three illustrative examples are supplied.
303
item Long time existence of solutions to 2D Navier-Stokes equations with inflow-outflow and heat convection
Piotr Kacprzyk
ABSTRACT. Global existence of regular solutions to the Navier-Stokes equations for velocity and pressure coupled with the heat convection equation for temperature in cylindrical pipe with inflow and outflow in the two-dimensional case is shown. We assume the slip boundary conditions for velocity and the Neumann condition for temperature. First an appropriate estimate is shown and next the existence of solutions is proved by the Leray-Schauder fixed point theorem.
343
item Robustness of nonuniform polynomial dichotomies for difference equations
Luis Barreira, Meng Fan, Claudia Valls and Jimin Zhang
ABSTRACT. For a nonautonomous dynamics with discrete time defined by a sequence of linear operators in a Banach space, we establish the robustness of polynomial contractions and of polynomial dichotomies under sufficiently small linear perturbations. In addition, we consider the general case of nonuniform polynomial behavior.
357
item Maps on bouquets of circles can be deformed to be coincidence-free
P. Christopher Staecker
ABSTRACT. We give a construction to remove coincidence points of continuous maps on graphs ($1$-complexes) by changing the maps by homotopies. When the codomain is not homeomorphic to the circle, we show that any pair of maps can be changed by homotopies to be coincidence free. This means that there can be no nontrivial coincidence index, Nielsen coincidence number, or coincidence Reidemeister trace in this setting, and the results of our previous paper ``A formula for the coincidence Reidemeister trace of selfmaps on bouquets of circles'' are invalid.
377
item Fixed points of hemi-convex multifunctions
Shahram Rezapour, S. M. A. Aleomraninejad and Naaser Shahzad
ABSTRACT. The notion of hemi-convex multifunctions is introduced. It is shown that each convex multifunction is hemi-convex, but the converse is not true. Some fixed point results for hemi-convex multifunctions are also proved.
383



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