18,109 research outputs found
Second order splitting of a class of fourth order PDEs with point constraints
We formulate a well-posedness and approximation theory for a class of generalised saddle point problems with a specific form of constraints. In this way we develop an approach to a class of fourth order elliptic partial differential equations with point constraints using the idea of splitting into coupled second order equations. An approach is formulated using a penalty method to impose the constraints. Our main motivation is to treat certain fourth order equations involving the biharmonic operator and point Dirichlet constraints for example arising in the modelling of biomembranes on curved and flat surfaces but the approach may be applied more generally. The theory for well-posedness and approximation is presented in an abstract setting. Several examples are described together with some numerical experiments
On the Optimality of Functionals over Triangulations of Delaunay Sets
In this short paper, we consider the functional density on sets of uniformly
bounded triangulations with fixed sets of vertices. We prove that if a
functional attains its minimum on the Delaunay triangulation, for every finite
set in the plane, then for infinite sets the density of this functional attains
its minimum also on the Delaunay triangulations
The Ultrarelativistic Kerr-Geometry and its Energy-Momentum Tensor
The ultrarelativistic limit of the Schwarzschild and the Kerr-geometry
together with their respective energy-momentum tensors is derived. The approach
is based on tensor-distributions making use of the underlying Kerr-Schild
structure, which remains stable under the ultrarelativistic boost.Comment: 16 pages, (AMS-LaTeX), TUW-94-0
2010 Estimated Cost of Producing Hops in the Yakima Valley, Washington State
The enterprise budget provides estimates of production costs for a well-managed hop enterprise in Yakima Valley, Washington as of 2010. Three producer scenarios are presented to demonstrate how the enterprise budget can be used to evaluate situations in which the producer may find him/herself. An interactive Excel Workbook is developed and detailed instructions are provided to allow users to input their own data or make changes to the existing spreadsheets.enterprise budget, hops, Washington
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