Electronic Journal of Differential Equations
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The Electronic Journal of Differential Equations
is hosted by the Department of Mathematics at Texas State University. Since its foundation in 1993, this ejournal has been dedicated to the rapid dissemination of high quality research in mathematics.
EJDE Journal Website: http://ejde.math.txstate.edu/
Recent Submissions

Multiplicity of Solutions for Quasilinear Elliptic Boundaryvalue Problems
(Texas State University, Department of Mathematics, 19990616)This paper is concerned with the existence of multiple solutions to the boundaryvalue problem (ϕp(uf))f = λϕq (u)+ f (u) in (0, 1) , u(0) = u(1) = 0, where p, q > 1, ϕx(y) = yx−2y, λ is a real parameter, and f is a ... 
Boundaryvalue Problems for the Onedimensional pLaplacian with Even Superlinearity
(Texas State University, Department of Mathematics, 19990308)This paper is concerned with a study of the quasilinear problem −(uIp−2uI)I = up − λ, in (0, 1) , u(0) = u(1) = 0, where p >1 and λ ∈ R are parameters. For λ > 0, we determine a lower bound for the number of solutions ... 
Periodic Traveling Waves for a Nonlocal Integrodifferential Model
(Texas State University, Department of Mathematics, 19990819)We establish the existence, uniqueness and stability of periodic traveling wave solutions to an intregodifferential model for phase transitions. 
A Note on Quasilinear Elliptic Eigenvalue Problems
(Texas State University, Department of Mathematics, 19991130)We study an eigenvalue problem by a nonsmooth critical point theory. Under general assumptions, we prove the existence of at least one solution as a minimum of a constrained energy functional. We apply some results on ... 
The Effect of Thin Coatings on Second Harmonic Generation
(Texas State University, Department of Mathematics, 19990920)The effect of thin coatings of nonlinear material on second harmonic generation is studied in this paper. Asymptotic expansions of the fields inside a thin nonlinear coating are performed. The convergence of these formal ... 
On the Prescribedperiod Problem for Autonomous Hamiltonian Systems
(Texas State University, Department of Mathematics, 19980220)Asymptotically quadratic and subquadratic autonomous Hamiltonian systems are considered. Lower bounds for the number of periodic solutions with a prescribed minimal period are obtained. These bounds are expressed in terms ... 
On a Generalized Reflection Law for Functions Satisfying the Helmholtz Equation
(Texas State University, Department of Mathematics, 19990604)We investigate a generalized point to point reflection law for the solutions of the Helmholtz equation in two independent variables, obtaining results that include some previously known results of Khavinson and Shapiro as ... 
Existence of Continuous and Singular Ground States for Semilinear Elliptic Systems
(Texas State University, Department of Mathematics, 19980116)We study existence results of a curve of continuous and singular ground states for the system. Δu = α(x) f(v) Δv = β(x) g(u), where x ∈ R(N) \ {0}, the functions ∫ and g are increasing Lipschitz continuous functions ... 
On MultiLump Solutions to the NonLinear Schrodinger Equation
(Texas State University, Department of Mathematics, 19981115)We present a new approach to proving the existence of semiclassical bound states of the nonlinear Schrodinger equation which are concentrated near a finite set of nondegenerate critical points of the potential function. ... 
On Tykhonov's Theorem for Convergence of Solutions of Slow and Fast Systems
(Texas State University, Department of Mathematics, 19980709)Slow and fast systems gain their special structure from the presence of two time scales. Their analysis is achieved with the help of Singular Perturbation Theory. The fundamental tool is Tykhonov's theorem which describes ... 
Existence and Regularity Results for the Gradient Flow for pHarmonic Maps
(Texas State University, Department of Mathematics, 19981221)We establish existence and regularity for a solution of the evolution problem associated to pharmonic maps if the target manifold has a nonpositive sectional curvature. 
Stability of Strong Detonation Waves and Rates of Convergence
(Texas State University, Department of Mathematics, 19980318)In this article, we prove stability of strong detonation waves and find their rate of convergence for a combustion model. Our results read as follows: I) There exists a global solution that converges exponentially in time ... 
Partial Exact Controllability for the Linear ThermoViscoelastic Model
(Texas State University, Department of Mathematics, 19980620)The problem of partial exact controllability for linear thermoviscoelasticity is considered. Using classical multiplier techniques, a boundary observability inequality is established under smallness restrictions on coupling ... 
Instability of Discrete Systems
(Texas State University, Department of Mathematics, 19981208)In this paper, we give criteria for instability and asymptotic instability for the null solution to the nonautonomous system of difference equations y(t + 1) = A(t)y(t) + f(t,y(t)), f(t,0) = 0, when the system x(t + 1) ... 
Existence and Multiplicity of Solutions to a pLaplacian Equation with Nonlinear Boundary Condition
(Texas State University, Department of Mathematics, 19980410)We study the nonlinear elliptic boundary value problem Au = f(x,u) in Ω, Bu = g(x,u) on ∂Ω, where A is an operator of pLaplacian type, Ω is an unbounded domain in ℝ(N) with noncompact boundary, and f and g are subcritical ... 
Symmetry and Convexity of Level Sets of Solutions to the Infinity Laplace's Equation
(Texas State University, Department of Mathematics, 19981209)We consider the Dirichlet problem Δ∞u = f(u) in Ω, u = 0 on ∂Ω, where Δ∞u = u(x)(i), u(x)(j), u(x)(i)(x)j) and f is a nonnegative continuous function. We investigate whether the solutions to this equation inherit geometrical ... 
Branching of Periodic Orbits from Kukles Isochrones
(Texas State University, Department of Mathematics, 19980513)We study local bifurcations of limit cycles from isochronous (or linearizable) centers. The isochronicity has been determined using the method of Darboux linearization, which provides a birational linearization for the ... 
On ReactionDiffusion Systems
(Texas State University, Department of Mathematics, 19981009)We consider reactiondiffusion systems which are strongly coupled. we prove that they generate analytic semigroups, find a characterization for the spectrum of the generator, and present some examples. 
Stationary Solutions for Generalized Boussinesq Models in Exterior Domains
(Texas State University, Department of Mathematics, 19981001)We establish the existence of a stationary weak solution of a generalized Boussinesq model for thermally driven convection in exterior domains. We use the fact that the exterior domain can be approximated by interior domains. 
QuasiGeostrophic Type Equations with Weak Initial Data
(Texas State University, Department of Mathematics, 19980612)We study the initial value problem for the quasigeostrophic type equations ∂θ / ∂t + u • ∇θ + (Δ)(λ)θ = 0, on ℝ(n) x (0, ∞), θ(x,0) = θ(0)(x), x ∈ ℝ(n), where λ(0 ≤ λ ≤ 1) is a fixed parameter and u = (u(j)) is divergence ...