Let P be a polyhedral domain occupying a convex volume. We prove that the size of a graded mesh of P with bounded vertex degree is within a factor O(H P ) of the size of any Delaunay mesh of P with bounded radius-edge ratio. The term HP depends on the geometry of P and it is likely a small constant when the boundaries of P are fine triangular meshes. There are several consequences. First, among...

An analytical model for computing submesh reliability is proposed in this paper. The system is considered operational as long as a functional submesh of the required size is available. We use the principle of inclusion and exclusion to find the exact probability of having a functional submesh within a partition of the mesh. The reliability of a partition is then used to approximate the submesh ...

We propose a new algorithm called Cyclic Exchange for all-to-all personalized exchange in a 2D mesh. This algorithm fully interleaves communication in both dimensions of a mesh. We have compared by simulation the performance of this algorithm with that of the Quadrant Exchange method previously proposed in the literature 2]. The results show that the new algorithm is faster for a range of machi...

We present new techniques for generation of unstructured meshes for geometries specified by implicit functions. An initial mesh is iteratively improved by solving for a force equilibrium in the element edges, and the boundary nodes are projected using the implicit geometry definition. Our algorithm generalizes to any dimension and it typically produces meshes of very high quality. We show a sim...

This paper deals with the upwind finite volume method applied to the linear advection equation on a bounded domain and with natural boundary conditions. We introduce what we call the geometric corrector which is a sequence associated with every finite volume mesh in Rnd and every non vanishing vector a of Rnd. First we show that if the continuous solution is regular enough and if the norm of th...

This paper presents the following algorithms to compute the sum of n d-bit integers on reconfigurable parallel computation models: (1) a constant-time algorithm on a reconfigurable mesh of the bit model of size &log(‘(‘)) n x dfi, (2) an O(log*n)-time algorithm on a reconfigurable mesh of the bit model of size dm x ddm, (3) an O(logd + log*n)-time algorithm on a reconfigurable mesh of the word ...

When applying higher order finite elements to curved 3D domains in largescale accelerator simulations, complexities that arise include needing valid curved finite elements and the capability to track the movement of mesh refinement in the critical domains. This paper presents a procedure which combines Bézier mesh curving and size driven mesh adaptation technologies to address those requirement...

New uniform estimates for multigrid algorithms are established for certain non-symmetric indefinite problems. In particular, we are concerned with the simple additive algorithm and multigrid (V(1 , 0)-cycle) algorithms given in [5]. We prove, without full elliptic regularity assumption, that these algorithms have uniform reduction per iteration, independent of the finest mesh size and number of...

This paper presents a fast and efficient contiguous allocation strategy for 3D mesh multicomputers, referred to as Turning Busy List (TBL for short), which can identify a free sub-mesh of the requested size as long as it exists in the mesh system. Turning means that the orientation of the allocation request is changed when no sub-mesh is available in the requested orientation. The TBL strategy ...

The purpose of this study was determine the selectivity properties of gillnet used in Roach (Rutilus rutilus) fishery in the Lake Uluabat. In the fishery works, 7 different gill net which were 100 meters in length and 32, 40,50, 60,70,80 and 90 mmmesh size with a same thickness and depth of 50 mesh as vertically have been used. Field work was carried out monthly in a period of January 2011 and ...