The index-permutation graph (IPG) model is a natural extension of the Cayley graph model, and super-IPGs form an efficient class of IPGs that contain a wide variety of networks as subclasses. In this paper, we derive ...
详细信息
The index-permutation graph (IPG) model is a natural extension of the Cayley graph model, and super-IPGs form an efficient class of IPGs that contain a wide variety of networks as subclasses. In this paper, we derive a number of efficient algorithms and embeddings for super-IPGs, proving their versatility. We show that a multitude of important networks can also be emulated in super-IPGs with optimal slowdown. Also, the intercluster diameter average intercluster distance, and bisection bandwidth of suitably constructed super-IPGs are optimal within small constant factors. Finally we show that when parallel computers, built as multiple chip-multiprocessors (MCMP), are based on super-IPGs, they can significantly outperform those based on hypercubes, k-ary n-cubes, and other networks in carrying out communication-intensive tasks.
We describe the design and implementation of efficient parallel algorithms, and a software library for the parallel implementation of compressed octree data structures. Octrees are widely used in supporting hierarchic...
详细信息
This paper presents results which improve the efficiency of parallel algorithms for computing the minimum spanning trees. For an input graph with n vertices and m edges our EREW PRAM algorithm runs in O(log n) time wi...
详细信息
This paper presents results which improve the efficiency of parallel algorithms for computing the minimum spanning trees. For an input graph with n vertices and m edges our EREW PRAM algorithm runs in O(log n) time with O((m+n) rootlog n) operations. Our CRCW PRAM algorithm runs in O(log n) time with O((m + n) log log n) operations. We also show that for dense graphs we can achieve O(log n) time with O(n(2)) operations on the EREW PRAM. (C) 2002 Published by Elsevier Science B.V.
In this paper, we present deterministic parallel algorithms for the convex hull of sorted points and their application to a related problem. The algorithms are proposed for the coarse grained multicomputer (CGM) model...
详细信息
In this paper, we present deterministic parallel algorithms for the convex hull of sorted points and their application to a related problem. The algorithms are proposed for the coarse grained multicomputer (CGM) model. We first propose a cost optimal parallel algorithm for computing the problem with a constant number of communication rounds for n/p greater than or equal to P-2, where n is the size of an input and p is the number of processors. Next we propose a cost optimal algorithm, which is more complicated, for n/q greater than or equal to p(epsilon). where 0 < epsilon < 2. From the above two results, we can compute the convex hull of sorted points with O(n/p) computation time and a constant number of communication rounds for n/p greater than or equal to P-epsilon. where epsilon > 0. Finally we show an application of our convex hull algorithms. We solve the convex layers for d lines in O(n log n/p) computation time with a constant number of communication rounds. The algorithm is also cost optimal for the problem.
In application areas such as geographical information systems, the Euclidean metric is often less meaningfully applied to determine a shortest path than metrics which capture, through weights, the varying nature of th...
详细信息
Adaptive multilevel methods are methods for solving partial differential equations that combine adaptive grid refinement with multigrid solution techniques. These methods have been shown to be very effective on sequen...
详细信息
In this note we describe deterministic parallel algorithms for planar point location and for building the Voronoï Diagram of n co-planar points. These algorithms are designed for BSP/CGM-like models of computatio...
详细信息
In this note we describe deterministic parallel algorithms for planar point location and for building the Voronoï Diagram of n co-planar points. These algorithms are designed for BSP/CGM-like models of computation, where p processors, with O(n/p) O(1) local memory each, communicate through some arbitrary interconnection network. They are communication-efficient since they require, respectively, O(1) and O(log p) communication steps and O(n log n/p) local computation per step. Both algorithms require O(n/p) = Ω(p) local memory.
Proposes a new parallel algorithm for computing path expressions, named the "parallel cascade semi-join" (PCSJ) algorithm. Moreover, a new scheduling strategy called the "right-deep zigzag tree" is...
详细信息
ISBN:
(纸本)0769509967
Proposes a new parallel algorithm for computing path expressions, named the "parallel cascade semi-join" (PCSJ) algorithm. Moreover, a new scheduling strategy called the "right-deep zigzag tree" is designed to further improve the performance of the PCSJ algorithm. The experiments have been implemented in a distributed and parallel NOW (network of workstations) environment. The results show that the PCSJ algorithm outperforms two other parallel algorithms [the parallel forward pointer chasing (PFPC) algorithm and the index-splitting parallel algorithm (IndexSplit)] when computing path expressions with restrictive predicates, and that the right-deep zigzag tree scheduling strategy has a better performance than the right-deep tree scheduling strategy.
This paper constructs a class of parallel Adams algorithms for the systems of delay differential equations. The results on convergence and stability are given. The theoretical analysis and numerical test shows that th...
详细信息
This paper constructs a class of parallel Adams algorithms for the systems of delay differential equations. The results on convergence and stability are given. The theoretical analysis and numerical test shows that this algorithm is effect and comparable.
暂无评论