A method for optimising a pre-existing mesh of tetrahedral ®nite elements is described. It is based on a series of mesh connectivity and node position searches of the landscape de®ning mesh quality. A Riemannian metric, re¯ecting the a posteriori error measure, is used to calculate element size and shape. A functional is de®ned which embodies both shape and size quality of an element with respe...

On a mesh-connected computer, moving data across the mesh is the most time-consuming operation in many algorithms. This time can be reduced by using a mesh with smaller diameter, i.e., with fewer processing elements. To accomodate inputs of the same size, this requires that the processors have more memory. For image processing and graph theoretic algorithms we analyze the time as a function of ...

In this paper we present two eecient algorithms for general preex computations (GPC, for sort) on meshes with multiple broadcasting and reconngurable meshes respectively. On a mesh with multiple broadcasting of size n n, the GPC problem of size kn (1 k n) can be solved in O(log n) time if k = 1, and in O(k log n log k) time if 2 k n. On a reconngurable mesh of size n n, the GPC problem of size ...

We introduce a scheme for constructing a CatmullClark subdivision surface that interpolates the vertices of a quadrilateral mesh with arbitrary topology. The basic idea here is to progressively modify the vertices of an original mesh to generate a new control mesh whose limit surface interpolates all vertices in the original mesh. The scheme is applicable to meshes with any size and any topolog...

A hierarchical simplicial mesh is a recursive decomposition of space into cells that are simplices. Such a mesh is compatible if pairs of neighboring cells meet along a single common face. Compatibility condition is important in many applications where the mesh serves as a discretization of a function. Enforcing compatibility involves refining the simplices of the mesh further, thus generates a...

This paper proposes an algorithm for generating a mesh that is similar to a given reference mesh in particular features. In the design process, similar kinds of meshes are generated for the same shape or similar shapes repeatedly. Once a mesh having the desired features is obtained, our algorithm can generate the succeeding meshes efficiently by imitating a selected set of features of the refer...

Mariculture of tropical sea cucumbers is promising, but the nursery rearing of juveniles is a bottleneck for farming and sea ranching. We conducted four medium-scale experiments lasting 3-6 weeks, using thousands of cultured juvenile sandfish Holothuria scabra, to optimise nursery rearing in mesh enclosures in earthen seawater ponds and to test rearing in enclosures in the sea. In one experimen...

A graph G is an interval graph if there is a one-one correspondence between its vertices and a family I of intervals, such that two vertices in G are adjacent if and only if their corresponding intervals overlap. In this context, the family I of intervals is referred to as an interval model of G. Recently, a powerful architecture called the reconngurable mesh has been proposed: in essence, a re...

In this article, we first consider some penalized finite element methods for the stationary Navier-stokes equations, based on the finite element space pair (Xh, Mh) which satisfies the discrete inf-sup condition for the P2−P0 element or does not satisfy the discrete inf-sup condition for the P1−P0 element. Then, we consider two-level penalty finite element methods which involve solving one smal...