in exterior domains in Rn where f : (0,∞) → (0,∞) is continuous function. We give lower bounds on the growth of f(s) at s = 0 and/or s = ∞ such that inequality (0.1) has no C positive solution in any exterior domain of Rn. Similar results were obtained by Armstrong and Sirakov [Nonexistence of positive supersolutions of elliptic equations via the maximum principle, Comm. Partial Differential Eq...

Among various barycentric coordinates and their extensions, the linear and cubic (Hermite) Gordon-Wixom transfinite interpolation schemes deliver the most accurate approximations of the harmonic and biharmonic functions, respectively. However interpolation properties of the original Gordon-Wixom interpolations are studied for convex domains only and, therefore, their current practical importanc...

The evaluation of sums (matrix–vector products) of the solutions of the three-dimensional biharmonic equation can be accelerated using the fast multipole method, while memory requirements can also be significantly reduced. We develop a complete translation theory for these equations. It is shown that translations of elementary solutions of the biharmonic equation can be achieved by considering ...

We study a weakly over-penalized symmetric interior penalty method for the biharmonic problem that is intrinsically parallel. Both a priori error analysis and a posteriori error analysis are carried out. The performance of the method is illustrated by numerical experiments. 1. Introduction. Recently, it was noted in [9] that the Poisson problem can be solved by a weakly over-penalized symmetric...

The aim of this article is to establish the existence of at least three‎ ‎solutions for a perturbed $p$-biharmonic equation depending on two‎ ‎real parameters‎. ‎The approach is based on variational methods‎.

The paper deals with special types of $L$-ordered sets, $L$-fuzzy complete lattices, and fuzzy directed complete posets.First, a theorem for constructing monotone maps is proved, a characterization for monotone maps on an $L$-fuzzy complete lattice is obtained, and it's proved that if $f$ is a monotone map on an $L$-fuzzy complete lattice $(P;e)$, then the least fixpoint of $f$ is meet of a spe...

In this paper, we study B-focal curves of biharmonic B -general helices according to Bishop frame in the Heisenberg group Heis   Finally, we characterize the B-focal curves of biharmonic B- general helices in terms of Bishop frame in the Heisenberg group Heis        

We consider a finite element method based on biorthogonal or quasi-biorthogonal systems for the biharmonic problem. The method is based on the primal mixed finite element method due to Ciarlet and Raviart for the biharmonic equation. Using different finite element spaces for the stream function and vorticity, this approach leads to a formulation only based on the stream function. We prove optim...