基于流水光总线阵列的快速矩阵乘法运算

基于流水光总线的可重构线性阵列系统(LARPBS)是一种建立在光总线上的并行计算模型,许多研究工作者已经在该模型上设计出了一些高效的并行算法。该文主要介绍了LARPBS模型及其快速矩阵乘法运算,从而使人们更加了解光总线计算模型及其优越性,为今后进一步研究光总线模型及其并行算法奠定了基础。     

基于流水光总线阵列的快速并行排序算法

基于流水光总线的可重构线性阵列系统(LARPBS)是一种建立在光总线上的并行计算模型。本文提出了一种基于LARPBS模型的快速排序并行算法，该算法使用n个处理器，对关 键字位数固定的n个记录可以在O(1)时间完成排序；对于关键字位数不固定的n个记录，可以在O(d)时间完成排序，这里d为关键字的最大位数。     

基于流水光总线阵列的快速矩阵运算

矩阵运算是最重要的数值计算,基于流水光总线的可重构线性阵列系统(LARPBS)是一种建立在光总线上的并行高效计算模型。该文主要介绍LARPBS模型上的快速并行矩阵运算,从而使人们更加了解光总线计算模型及其优越性,为今后进一步研究光总线模型及其并行算法奠定基础。     

基于流水光总线阵列上Valiant并行归并排序的实现

基于流水总线的可重构线性阵列系统（LARPBS）是一种建立在光总线上的并行计算模型，许多研究工作者已经在该模型上设计出了一些高效的并行算法。文章提出了一种基于LARPBS模型上Vnliant并行归并的实现算法，利用该法对长度为N的序列进行排序，最坏情况下可以使用N个处理器在O（logNloglogN)时间完成。     

PRAM和LARPBS模型上的近似串匹配并行算法

近似串匹配技术在网络信息搜索、数字图书馆、模式识别、文本挖掘、IP路由查找、网络入侵检测、生物信息学、音乐研究计算等领域具有广泛的应用.基于CREW-PRAM(parallel random access machine with concurrent read and exclusive write)模型,采用波前式并行推进的方法直接计算编辑距离矩阵D,设计了一个允许k-差别的近似串匹配动态规划并行算法,该算法使用(m+1)个处理器,时间复杂度为O(n),算法理论上达到线性加速;采取水平和斜向双并行计算编辑距离矩阵D的方法,设计了一个使用((m+1)个处理器和O(n/(+m)时间的、可伸缩的、允许k-差别的近似串匹配动态规划并行算法,.基于分治策略,通过灵活拆分总线和合并子总线动态重构光总线系统,并充分利用光总线的消息播送技术和并行计算前缀和的方法,实现了汉明距离的并行计算,设计了两个基于LARPBS(linear arrays with reconfigurable pipelined bus system)模型的通信高效、可扩放的允许k-误配的近似串匹配并行算法,其中一个算法使用n个处理器,时间为O(m);另一个为常数时间算法,使用mn个处理器.     

基于流水光总线的可重构线性阵列模型

该文主要介绍基于流水光总线的可重构线性阵列系统(LARPBS)模型及其基本数据传输和操作,并以矩阵乘法和排序为例介绍了LARPBS上的并行算法及其设计方法。     

并行计算模型研究

并行计算模型是并行计算机基本特征的抽象，是并行算法设计和分析的基础，其重要性类似于顺序计算的存储程序模型，因而受到广泛的关注。虽然提出了大量的并行计算模型，但是仍无一通用模型。本文概递了并行计算模型的一些基本概念，介绍了理想计算模型的特征，讨论了一些典型的并行计算模型，综述了目前并行计算模型在异构计算环境的发展情况。     

并行计算模型的分类和评价

随着各种并行计算机体系结构的出现及并行计算在各学科领域中的广泛应用,需要并行计算模型用以研究并行计算性质,分析并行算法;简化并行软件设计。本文对并行计算模型给出一个评价准则,并以此对现有的并行计算模型进行分类和比较。     

一种改进的矩阵幂运算及其性能分析

基于流水光总线的可重构线性阵列系统是一种建立在光总线上的并行高效计算模型。该文给出了一种LARPBS模型上改进的矩阵幂运算并行算法,并对其可扩展性和复杂性进行分析,通过分析可以看出,该算法是目前速度最快、成本最优的并行矩阵幂运算算法。     

并行FFT算法在3种并行计算模型上的设计和分析*

本文研究在APRAM，BSP和LogP等3种并行计算模型上并行FFT算法的设计和分析;分析这3种模型的内在特性及其相互关系;评价它们在设计和分析并行算法时的可用性和可操作性．     

基于LARPBS模型的最大值查找算法

具备可重配置流水线总线的线性阵列LARPBS(1inear arrays with a reconfigurable pipelined bus systems)是近来出现的一种高效的并行计算模型．与理想的PRAM模型不同．LARPBS是现实可行的。基于LARPBS模型，Y．Pan介绍了2种宽度和精度任意的数据项的最大值查找算法：算法1使用了N^2／2个处理机、O(1)时间，它是目前时间最优的算法；算法2使用了N个处理机、O(loglogN)时间。本文介绍了2种最大值查找算法．时间复杂度同Y.Pan的算法，但所用处理机数减少了一半．这是对Y．Pan算法的重要改进。     

Permutation Routing on Reconfigurable Meshes

In this paper we present efficient algorithms for packet routing on the reconfigurable linear array and the reconfigurable two-dimensional mesh. We introduce algorithms that are efficient in the worst case and algorithms that are better on average. The time bounds presented are better than those achievable on the conventional mesh and previously known algorithms. We present two variants of the reconfigurable mesh. In the first model, M _r , the processors are attached to a reconfigurable bus, the individual edge connections being bidirectional. In the second model, M _mr , the processors are attached to two unidirectional buses. In this paper we present lower bounds and nearly matching upper bounds for packet routing on these two models. As a consequence, we solve two of the open problems mentioned in [9]. Received August 17, 1998; revised November 3, 1999.     

Efficient Parallel Algorithms for Hierarchical Clustering on Arrays with Reconfigurable Optical Buses

Clustering is a basic operation in image processing and computer vision, and it plays an important role in unsupervised pattern recognition and image segmentation. While there are many methods for clustering, the single-link hierarchical clustering is one of the most popular techniques. In this paper, with the advantages of both optical transmission and electronic computation, we design efficient parallel hierarchical clustering algorithms on the arrays with reconfigurable optical buses (AROB). We first design three efficient basic operations which include the matrix multiplication of two N×N matrices, finding the minimum spanning tree of a graph with N vertices, and identifying the connected component containing a specified vertex. Based on these three data operations, an O(log N) time parallel hierarchical clustering algorithm is proposed using N³ processors. Furthermore, if the connectivity of the AROB with four-port connection is allowed, two constant time clustering algorithms can be also derived using N⁴ and N³ processors, respectively. These results improve on previously known algorithms developed on various parallel computational models.     

Communication-Efficient Sorting Algorithms on Reconfigurable Array of Processors With Slotted Optical Buses

The reconfigurable array with slotted optical buses (RASOB) has recently received a lot of attention from the research community. In this paper, we first discuss the reconfiguration methods and communication capabilities of the RASOB architecture. Then, we use this architecture for the implementation of efficient sorting algorithms on the 1D RASOB and the 2D RASOB. Our parallel sorting algorithm on the 1D RASOB is based on an efficient divide-and-conquer scheme. It sortsNdata items usingNprocessors inO(k) communication cycles where k is the size of the data items to be sorted in bits. We further develop a parallel sorting algorithm on the 2D RASOB based on the sorting algorithm on the 1D RASOB in conjunction with the well known Rotatesort algorithm. Similarly, this algorithm sortsNdata items on a 2D RASOB of sizeNinO(k) communication cycles. These sorting algorithms are much more efficient than state-of-the-art sorting algorithms on reconfigurable arrays of processors withelectronicbuses using the same number of processors.     

Run-length chain coding and scalable computation of a shape''s moments using reconfigurable optical buses

The main contribution of this paper is the design of several efficient algorithms for modified run-length chain coding and for computing a shape's moments on arrays with reconfigurable optical buses. The proposed algorithms are based on the boundary representation of an object. Instead of using chain code, the boundary can be represented by a modified run-length chain code, where each entity represents a line segment (two adjacent corner pixels). The sequential nature of the chain code makes it difficult to be parallelized. We first propose two constant time algorithms for boundary extraction and run-length chain coding. To the authors' knowledge, these are the most time efficient algorithms yet published. Based on the modified run-length chain coding, and the advantages of both optical transmission and electronic computation, a constant time parallel algorithm for computing a shape's moments using N x N processors is proposed. Additionally, instead of using N x N processors, a scalable moment algorithm using r x r processors is also derived, where r < N. Based on the product of time and the number of processors used, both proposed parallel algorithms are time and cost optimal.     

L2 vector median filters on arrays with reconfigurableoptical buses

In spite of their good filtering characteristics for vector-valued image processing, the usability of vector median filters is limited by their high computational complexity. Given an N × N image and a W × W window, the computational complexity of vector median filter is O(W⁴N²). In this paper, we design three fast and efficient parallel algorithms for vector median filtering based on the 2-norm (L₂) on the arrays with reconfigurable optical buses (AROB). For 1 ⩽ p ⩽ W ⩽ q ⩽ N, our algorithms run in O(W⁴ log W/p⁴), O(W²N²/p ⁴q² log W) and O(1) times using p⁴N² / log W, p⁴q² / log W, and W⁴N² log N processors, respectively. In the sense of the product of time and the number of processors used, the first two results are cost optimal and the last one is time optimal     

Fast and scalable selection algorithms with applications to median filtering

The main contributions of this paper are in designing fast and scalable parallel algorithms for selection and median filtering. Based on the radix-/spl omega/ representation of data and the prune-and-search approach, we first design a fast and scalable selection algorithm on the arrays with reconfigurable optical buses (AROB). To the authors' knowledge, this is the most time efficient algorithm yet published, especially compared to the algorithms proposed by Han et al (2002) and Pan (1994). Then, given an N /spl times/ N image and a W /spl times/ W window, based on the proposed selection algorithm, several scalable median filtering algorithms are developed on the AROB model with a various number of processors. In the sense of the product of time and the number of processors used, most of the proposed algorithms are time or cost optimal.