LHL-立方体互连网络及其性质

并行计算系统一直是计算机科学中的重要研究领域,其互连网络的拓扑性质对整个网络的性能起着非常重要的作用.目前已经提出多种互连网络,其中超立方体具有对数级的直径、高连通度、对称性等很好的性质,故被用作多种并行机的处理器连接的拓扑结构.然而,超立方体并非所有性质都是最优的互连网络,且超立方体的许多变型结构具有许多比超立方体更好的性质,其中已经证明了局部扭立方体在直径、Hamilton连通性等方面都优于超立方体.给出在超立方体与局部扭立方体的顶点间的一种连接方式--超连接,从而得到一种称为LHL-立方体的新型网络,并对这种网络的以下性质进行了研究:顶点连通度、边连通度、Hamilton连通性、直径.研究结果表明,一个n维LHL-立方体是一个具有2n个顶点和n2n-1条边的n-正则图,n维LHL-立方体的顶点连通度和边连通度均为n,且是Hamilton连通的,直径上界为[n/2 ]+3.     

超级局部扭立方体互连网络及其性质

局部扭立方体是近年来提出的超立方体的一个变型,由于它的许多优越性质(如低直径),在并行处理领域越来越受到人们的重视.然而,像超立方体一样,它也有一个缺点,即要使局部扭立方体升级,就必须成倍地增加其顶点个数.为了解决这一问题,文中将顶点个数为2的次幂的局部扭立方体推广到具有任意个顶点的互连网络,提出了超级局部扭立方体(SLTC)的定义,并证明它保持了局部扭立方体的最高连通度、对数级的直径和顶点度数、Hamilton性质等方面的优良性质,从而证明了超级局部扭立方体是既保持了局部扭立方体的多种优越性质又易于升级的互连网络.     

交叉立方体环的Hamilton连通性和Pancyclicity性

交叉立方体是超立方体互连网络的一种变型,它的某些性质优于超立方体。例如,其直径几乎是超立方体的一半;当n≥3,交叉立方体CQn具有Hamilton连通性;当n≥2,所有长度在4到2n之间的圈都能够以扩张1嵌入CQn,即交叉立方体具有Pancyclity性。但是,交叉立方体同超立方体一样,当需要升级时,必须成倍增加结点。交叉立方体环互连网络CRN作为层次环互连网络HRN[8]的一种,可以有效地克服这个缺点,当需要升级时,只需在环上增加一个交叉立方体。在文中,证明了交叉立方体环互连网络仍然保持了交叉立方体具有的Hamilton连通性和Pancyclity性。     

二进制立方形递归网络的拓扑结构

二进制递归网络是一类具有良好拓扑性质和网络参数的互连网络模型.定义了一类特殊的二进制递归网络模型,即二进制立方形递归网络; 引入子网和超网的概念对其拓扑结构进行了分析研究; 证明了超立方体、扭n-立方体、广义扭立方体、交叉立方体、Mbius立方体和扭立方体连接网络都是这类特殊的二进制递归网络的具体实例.     

超级扭立方体互连网络及其性质

扭立方体是超立方体的一类变体,它具有比超立方体更好的性质。但是,同超立方体一样,它也是具有2n个顶点的n-正则图,故要使一个扭立方体的维数(即顶点度数)增加1(称为升级),就必须成倍地增加扭立方体中的顶点个数。为了解决这一问题,将具有2n个顶点的扭立方体的拓扑结构加以改变,得到了包含任意多个顶点的互连网络——超级扭立方体(STN)。证明了超级扭立方体保持了扭立方体的最高连通度、对数级的直径和顶点度数、Hamilton性质、连通度级的tp-可诊断度等方面的优良性质,更进一步地,由于它包含了任意多个顶点,所以对它的升级只需增加任意多个顶点,从而克服了扭立方体的升级必须成倍增加其顶点个数的缺点。     

局部扭立方体网络中网络嵌入问题的研究

局部扭立方体网络LTQ_n(Locally Twisted Cube)作为超立方体网络Q_n(Hypercube)的优化变种网络,具有很多优良的特性。依据局部扭立方体网络的性质及图嵌入的理论提出二项树、交换超立方体网络和超立方体网络嵌入到局部扭立方体网络的方案,并严格证明了这几种嵌入映射的扩张率、拥塞度及负载等都是最小的,这说明了局部扭立方体网络具有很好的通用性。     

交叉扭立方体互联网络及其性质

扭N立方体是近年来提出的一种新型变体网络结构.通过X-变换操作使得存在2n个顶点的超立方体的网络直径从N减少到N-1,减少了网络规模增大时所需要的网络开销,从而受到了广泛的欢迎.与超立方体一样,扭N立方体也存在缺点,如果增加扭N立方体的维数,会成倍增加扭N立方体的顶点个数.为了解决这一问题,本文通过扭N立方体的结构,提出了交叉扭立方体的定义,并给出了相应的拓扑结构网络图,证明了交叉扭立方体的部分子网与超立方体网络同构,同时研究了交叉扭立方体的网络直径、连通度等问题.通过上述拓扑结构的基本性质的研究,得到了交叉扭立方体的性能优于扭N立方体的重要结论.     

扭立方体连接网络结构的研究与分析

根据交叉立方体（CQn）的结构与关联对的概念,对扭立方体连接网络（TNn）的结构特性进行了分析,证明了当[n5]时,TNn是不连通的,并且不连通的结点数占整个网络结点数的一半。通过分析扭立方体连接网络的错误所在,提出了一种新型网络结构——扭交叉立方体（TCQn）,证明了该网络结构是完全连通的,初步研究了其基本网络性质,如正则性,连通度,容错度,递归性等,表明TCQn具有与CQn同样优秀的网络性质。     

k-元n-立方体网络局部通信模式下的性能模型

大规模并行计算机互连网络的设计对并行应用程序的执行效率有重要影响,k-元n-立方体是广泛使用的拓扑结构.局部通信是并行应用的主要通信模式之一,研究局部通信模式下互连网络的性能有重要意义,已有分析模型缺乏对这方面的充分研究.引入局部通信率和局部通信区域半径组成的二元参数,刻画k-元n-立方体网络节点间通信的空间局部性.利...     

超级交叉立方体互连网络上的圈嵌入

作为超立方体的变型，交叉立方体同时具有一些比超立方体优越的性质，但类似于超立方体，它的升级也伴随着顶点个数的增加而成倍中增加。为了解决这一问题，一种称为超级交叉立方体（SCC）的互连网络被提了出来。有关文献已证明，SCC很好地保持了交叉立方体在顶点度数，直径和连通度方面的优越性质，而且其升级可以增加任意多个顶点。用图嵌入技术讨论了SCC模拟环网络的能力，证明了长度为4到N的任一圈都能以扩张1嵌入具有N个顶点的SCC，从而证明了SCC模拟环网络的能力与交叉立方体完全相同。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.