一种评价2—DMesh网络性能的方法

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分布式系统中自然联结的优化算法分析

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CD WinBench99 CDROM测试专家

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CHIP这样测试 DVD-ROM驱动器

随着ＤＶＤ－ＲＯＭ驱动器产品性能的提高和操作系统的演变,ＣＨＩＰ在此次测试中采用了Ｄｅｌｌ Ｄｉｍｅｎｓｉｏｎ８２００整机作为测试平台,它配有Ｐｅｎｔｉｕｍ４ ２．０ＧＨｚ处理器、Ｉｎｔｅｌ ８５０芯片组主板、２５６ＭＢ ＲＤＲＡＭ内存,而操作     

世界顶级游戏3D卡：Geforce256 DDR

大概在２－３个月前．ｎＶＩＤＩＡ向全世界公布了举世瞩目的Ｇｅｆｏｒｃｅ２５６图形加速卡。在Ｑｕａｋｅ３　Ｔｅｓｔ中采用高分辨率和１６的产品一直在３２位色下工作得一般。同样在Ｑｕａｋｅ３中,Ｇｅｆｏｒｃｅ２５６使用３２位色后,画面没有成倍的变漂亮,但是速度却下降得不象样、原因之一就是当时的Ｇｅｆｏｒｃｅ２５６采用的是ＳＤＲＡＭ,ＳＤＲＡＭ虽然便宜,但是在高分辨率下内存带宽就显得不够用了。最近,ｎＶＩＤＩＡ得到内存厂商的支持获得大量的ＤＤＲ ＳＧＲＡＭ,ＤＤＲ　ＳＧＲＡＲ的工作频率是普通ＳＤＲＡＭ的…     

Windows98启动盘的新特性及应用

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电脑文摘

电脑文摘９８０３２计算／ＤＲＡＭＴＲＡＭＳ的硬件设计方法／／Ｍｉ－ｃｒｏｐｒｏｃｅｓｓｏｒｓａｎｄＭｉｃｒｏｓｙｓｔｅｍｓ．－１９９７，２０（９）．－５６７－５７７本文描述合并了一个ｌｎｍｏｓＩＭＳＴ４２５整数器或者ＩＭＳＴ８０５浮点晶片计算机（与动...     

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电脑文摘９４０１１用ＰＣ－ＡＴ按口卡实现ＦＤＤＩ双联站∥Ｍｉｃｒｏｐｒｏ－ｃｅｓｓｏｒｓａｎｄＭｉｃｒｏｓｙｓｔｅｍｓ．—１９９３，１７（２）．—１０１～１０７介绍用ｐｃ－ＡＴ接口卡实现ＦＤＤＩ双联站的设计方法。研究采用的是供ＭＡＣ和ＰＨＹ控制器用的...     

自己家庭的PC小影院

ＣＰＵ：奔腾Ⅱ４００ Ｓｌｏｔ　１／５１２Ｋ散主板：升技 ＢＥ６ Ｉｎｔｅｌ ４４０ＢＸ／ＡＴＸ／Ｓｌｏ－１／支持 １００ＭＨｚ外频／支持 Ｕｌｔｒａ ＤＭＡ／６６硬盘： ＩＢＭ 　Ｄｅｓｋｓｔａｒ ＤＪＮＡ３７１３６０ １３． ６Ｇ／ ＵＤＭＡ／６６／２Ｍ／７２００ｒｐｍ／ＩＤＥ／全国联保三年内存：日立／６４Ｍ ６ｎｓ／１６８ＰＩＮ ＳＤＲＡＭ／ＰＣ１００／原装显示卡： ＡＴＩ ＸＰＥＲＴ１２８ Ｒａｇｅ １２８ＧＬ／１６ＭＢ ＳＤＲＡＭ／ＡＧＰ ２Ｘ声卡： ＣＲＥＡＴＩＶＥ ｓｂ ＰＣＩ １２８（ｄｉｇｉｔａｌ）１２８位复音／１２８位硬波表／ＰＣＩ光驱：先锋 ＤＶＤ－Ａ０３Ｓ ６Ｘ ＤＶＤ／３２Ｘ ＣＤ－ＲＯＭ／无托盘／吸盘式结构显示器： ＬＧ ７７５ＦＴ １７″ ０． ２４ｍｍ点距／最大分辨率 １２８０ ｘ １０２４／１１０ＭＨｚＭＯＤＥＭ： ＴＰ－ ＬＩＮＫ ５６Ｋ／Ｒｏｃｋｗｅｌｌ／Ｖ．９０＋ Ｋ５６／内置软驱：三菱１．４４″     

Intense 3D~(TM) 图形加速器

Ｉｎｔｅｎｓｅ３ＤＴＭ图形加速器ＰＣ工业界最快速的３Ｄ图形处理用户如要把ＰＣ或工作站升级到具有３Ｄ图形处理能力，那么插入Ｉｎｔｅｎｓｅ３ＤＯｐｅｎＧＬ○Ｒ图形加速器就能如愿以偿。Ｉｎｔｅｎｓｅ３Ｄ使用倍受赞扬的Ｉｎ－ｔｅｒｇｒａｐｈＴＤＺＴＭ工作站上...     

使用二维分层网格的视频对象描述

二维网格压缩技术是MPEG－4标准的一个核心实验,使用分层网络技术可以提高网络跟踪的效果,提出了一种新的分层网格简化技术,进一步提高了网格的跟踪效果。     

Probabilistic analysis on mesh network fault tolerance

Mesh networks are among the most important interconnection network topologies for large multicomputer systems. Mesh networks perform poorly in tolerating faults in the view of worst-case analysis. On the other hand, such worst cases occur very rarely in realistic situations. In this paper, we study the fault tolerance of 2-D and 3-D mesh networks under a more realistic model in which each network node has an independent failure probability. We first observe that if the node failure probability is fixed, then the connectivity probability of these mesh networks can be arbitrarily small when the network size is sufficiently large. Thus, it is practically important for multicomputer system manufacture to determine the upper bound for node failure probability when the probability of network connectivity and the network size are given. We develop a novel technique to formally derive lower bounds on the connectivity probability for 2-D and 3-D mesh networks. Our study shows that these mesh networks of practical size can tolerate a large number of faulty nodes thus are reliable enough for multicomputer systems. For example, it is formally proved that as long as the node failure probability is bounded by 0.5%$0.5\%$, a 3-D mesh network of up to a million nodes remains connected with a probability larger than 99%$99\%$.     

On fault tolerance of 3-dimensional mesh networks

In this paper, the concept of k-submesh and k-submesh connectivity fault tolerance model is proposed. And the fault tolerance of 3-D mesh networks is studied under a more realistic model in which each network node has an independent failure probability. It is first observed that if the node failure probability is fixed, then the connectivity probability of 3-D mesh networks can be arbitrarily small when the network size is sufficiently large. Thus, it is practically important for multicomputer system manufacturer to determine the upper bound for node failure probability when the probability of network connectivity and the network size are given. A novel technique is developed to formally derive lower bounds on the connectivity probability for 3-D mesh networks. The study shows that 3-D mesh networks of practical size can tolerate a large number of faulty nodes thus are reliable enough for multicomputer systems. A number of advantages of 3-D mesh networks over other popular network topologies are given.     

An Alternative Mapping of 3-D Space onto Processor Arrays

Algorithms for many geometric and physical algorithms rely on a decomposition of 3-D space. Typically, a cubical decomposition is used, where each cubical cell is adjacent to, and may interact with, as many as 26 neighboring cells. In this paper, we explore an alternate structure, the woven mesh, that arises from a decomposition based on truncated octahedra. An algorithm is given to map 3-D space into the cells of the woven mesh and we give mappings which exploit the lower degree of the woven mesh, 14 rather than 26, to obtain better embeddings of 3-D space onto low degree processor arrays. We show that the woven mesh can be embedded with dilation 2 and congestion 4 onto a 3-D mesh. A dilation 3, congestion 8 embedding onto a 4-regular graph is also presented. These embeddings achieve optimal dilation on their respective host graphs; we prove that there does not exist a dilation 2 embedding of the woven mesh on any 4-regular graph. Of particular interest is the proof technique which was guided by deductive computation.     

Deadlock-free multicast wormhole routing in 2-D mesh multicomputers

Multicast communication services, in which the same message is delivered from a source node to an arbitrary number of destination nodes, are being provided in new-generation multicomputers. Broadcast is a special case of multicast in which a message is delivered to all nodes in the network. The nCUBE-2, a wormhole-routed hypercube multicomputer, provides hardware support for broadcast and a restricted form of multicast in which the destinations form a subcube. However, the broadcast routing algorithm adopted in the nCUBE-2 is not deadlock-free. In this paper, four multicast wormhole routing strategies for 2-D mesh multicomputers are proposed and studied. All of the algorithms are shown to be deadlock-free. These are the first deadlock-free multicast wormhole routing algorithms ever proposed. A simulation study has been conducted that compares the performance of these multicast algorithms under dynamic network traffic conditions in a 2-D mesh. The results indicate that a dual-path routing algorithm offers performance advantages over tree-based, multipath, and fixed-path algorithms     

混合预测模型在网络性能预测中的应用

分析比较不同预测模型的特点及应用条件,基于一次指数平滑模型、二次指数平滑模型和灰色系统模型GM（1,1）,提出并设计能适应网络性能数据序列的混合预测模型。实际应用证明,该模型预测效果良好,能够较好地实现一段时间内的网络性能预测任务。     

Three-dimensional motion estimation via matrix completion

Three-dimensional motion estimation from multiview video sequences is of vital importance to achieve high-quality dynamic scene reconstruction. In this paper, we propose a new 3-D motion estimation method based on matrix completion. Taking a reconstructed 3-D mesh as the underlying scene representation, this method automatically estimates motions of 3-D objects. A "separating + merging" framework is introduced to multiview 3-D motion estimation. In the separating step, initial motions are first estimated for each view with a neighboring view. Then, in the merging step, the motions obtained by each view are merged together and optimized by low-rank matrix completion method. The most accurate motion estimation for each vertex in the recovered matrix is further selected by three spatiotemporal criteria. Experimental results on data sets with synthetic motions and real motions show that our method can reliably estimate 3-D motions.     

基于表面粗糙度的三维模型质量评价研究

数字水印的嵌入会引起三维模型数据的失真,正确评价含水印三维模型的质量可以为三维水印算法的测评提供统一标准。提出了一种新的三维模型质量的评价方法,它首先利用网格模型中二面角为基本度量单位计算出整个原始三维模型的粗糙度,然后在嵌入水印以后用同样的方法计算出含水印三维模型的粗糙度,最后得到嵌入水印前后粗糙度的增量,并将其作为水印嵌入对三维模型造成的失真度的度量。大量实验结果表明,相比传统的质量评价方法,该方法更加适用于三维网格模型。该质量评价方法还可用于评价各种水印攻击对含水印三维模型造成损害的程度。     

Euclidean distance transform for binary images on reconfigurable mesh-connected computers.

The distance calculation in an image is a basic operation in computer vision, pattern recognition, and robotics. Several parallel algorithms have been proposed for calculating the Euclidean distance transform (EDT). Recently, Chen and Chuang proposed a parallel algorithm for computing the EDT on mesh-connected SIMD computers (1995). For an nxn image, their algorithm runs in O(n) time on a two-dimensional (2-D) nxn mesh-connected processor array. In this paper, we propose a more efficient parallel algorithm for computing the EDT on a reconfigurable mesh model. For the same problem, our algorithm runs in O(log(2)n) time on a 2-D nxn reconfigurable mesh. Since a reconfigurable mesh uses the same amount of VLSI area as a plain mesh of the same size does when implemented in VLSI, our algorithm improves the result in [3] significantly.