检索结果-内蒙古大学图书馆

International Conference on computer Supported Cooperative Work in Design

作者： Leonardo A. de C. Gatti Flávia Maria Santoro Vanessa T. Nunes NP2TEC - Research and Practice Group in Information Technology UNIRIO Rio de Janeiro Brazil NP2TEC-Research and Practice Group in Information Technology Department of Applied Informatics UNIRIO Federal University of Rio de Janeiro Rio de Janeiro Brazil COPPE - Systems Engineering and Computer Science Program UFRJ Rio de Janeiro Brazil

The main knowledge management challenges are to capture, store and reuse contextual knowledge generated during interactions that occur daily in an organization. In this paper, we propose an activity context-aware architecture to support knowledge management in working processes. The required features for this architecture are processing, reasoning and sharing contextual knowledge involving information about activities performed. We also present results from evaluation of our proposal — A-CoBrA — for a specific domain.

关键词： Knowledge management computer architecture Context modeling Collaborative work Proposals Information technology Informatics Service oriented architecture Ontologies Knowledge engineering

来源：评论

学校读者我要写书评

暂无评论

Using modal logics to express and check global graph properties

Using modal logics to express and check global graph propert...

引用

作者： Benevides, Mario R.F. Schechter, L. Menasché Computer Science Department Systems and Computer Engineering Program Federal University of Rio de Janeiro Rio de Janeiro Brazil Systems and Computer Engineering Program Federal University of Rio de Janeiro Rio de Janeiro Brazil

Graphs are among the most frequently used structures in computer science. Some of the properties that must be checked in many applications are connectivity, acyclicity and the Eulerian and Hamiltonian properties. In this work, we analyze how we can express these four properties with modal logics. This involves two issues: whether each of the modal languages under consideration has enough expressive power to describe these properties and how complex (computationally) it is to use these logics to actually test whether a given graph has some desired property. First, we show that these properties are not definable in a basic modal logic or in any bisimulation-invariant extension of it, like the modal μ-calculus. We then show that it is possible to express some of the above properties in a basic hybrid logic. Unfortunately, the Hamiltonian and Eulerian properties still cannot be efficiently checked. In a second attempt, we propose an extension of CTL* with nominals and show that the Hamiltonian property can be more efficiently checked in this logic than in the previous one. In a third attempt, we extend the basic hybrid logic with the ↓ operator and show that we can check the Hamiltonian property with optimal (NP) complexity in this logic. Finally, we tackle the Eulerian property in two different ways. First, we develop a generic method to express edge-related properties in hybrid logics and use it to express the Eulerian property. Second, we express a necessary and sufficient condition for the Eulerian property to hold using a graded modal logic. © The Author 2009. Published by Oxford University Press. All rights reserved.

关键词： Model checking

来源：评论

学校读者我要写书评

暂无评论

SpMT WaveCache: Exploiting thread-level parallelism in WaveScalar

SpMT WaveCache: Exploiting thread-level parallelism in WaveS...

引用

2009 WRI World Congress on computer science and Information engineering, CSIE 2009

作者： Pei, Songwen Wu, Baifeng Du, Min Chen, Gang Marzulo, Leandro A. J. Franca, Felipe M. G. School of Computer Science Fudan University 200433 Shanghai China Systems Engineering and Computer Science Program COPPE Rio de Janeiro Brazil

ISBN: (纸本)9780769535074

Speculative Multithreading (SpMT) increases the performance by means of executing multiple threads speculatively to exploit thread-level parallelism. By combining software and hardware approaches, we have improved the capabilities of previous WaveScalar ISA on the basis of Transactional Memory system for the WaveCache Architecture. Threads are extracted at the course of static compiling, and speculatively executed as a thread-level transaction that is supported by extra hardware components, such as Thread-Context-Table (TCT) and Thread-Memory-History (TMH). We have evaluated the SpMT WaveCache with 6 real benchmarks from SPEC, Mediabench and Mibench. On the whole, the SpMT WaveCache outperforms superscalar architecture ranging from 2X to 3X, and great performance gains are achieved over original WaveCache and Transactional WaveCache as well. © 2008 IEEE.

关键词： Memory architecture

来源：评论

学校读者我要写书评

暂无评论

Improving a web usability inspection technique using qualitative and quantitative data from an observational study

Improving a web usability inspection technique using qualita...

引用

SBES 2009 - 23rd Brazilian Symposium on Software engineering

作者： Conte, Tayana Vaz, Verônica Massolar, Jobson Mendes, Emilia Travassos, Guilherme Horta Manaus Brazil Systems Engineering and Computer Science Program COPPE UFRJ Rio de Janeiro Brazil Computer Science Department University of Auckland Auckland New Zealand

ISBN: (纸本)9780769538440

We have proposed a checklist-based usability inspection technique (WDP - Web Design Perspectives-Based Usability Evaluation) specific for Web applications' usability evaluation and we are following an experimentation-based methodology to support its development and improvement. This paper describes an observational study conducted, aimed at eliciting how inspectors apply the WDP technique. We discuss the quantitative and qualitative results of the result and their impact on improving the WDP technique. We analyzed the qualitative data using the procedures from the Grounded Theory (GT) method. © 2009 IEEE.

关键词： Inspection

来源：评论

学校读者我要写书评

暂无评论

Porantim: An approach to support the combination and selection of model-based testing techniques

Porantim: An approach to support the combination and selecti...

引用

2009 ICSE Workshop on Automation of Software Test, AST 2009

作者： Neto, Arilo Claudio Dias Travassos, Guilherme Horta Federal University of Rio de Janeiro Systems Engineering and Computer Science Program COPPE/UFRJ P.O. Box 68511 21941-972 Rio de Janeiro RJ Brazil

ISBN: (纸本)9781424437436

The technical literature regarding Model-based Testing (MBT) has several techniques with different characteristics and goals available to be applied in software projects. Besides the lack of information regarding these techniques, they could be applied together in a software project aiming at improving the testing coverage. However, this decision needs to be carefully analyzed to avoid loss of resources in a software project. Based on this scenario, this paper proposes an approach with the purpose of supporting the unique or combined selection of MBT techniques for a given software project considering two aspects: the adequacy level between MBT techniques and the software project characteristics and impact of more than one MBT technique in some testing process variables. At the end, preliminary results of an experimental evaluation are presented.

关键词： Model checking

来源：评论

学校读者我要写书评

暂无评论

SpMT WaveCache: Exploiting Thread-Level Parallelism in WaveScalar

SpMT WaveCache: Exploiting Thread-Level Parallelism in WaveS...

引用

computer science and Information engineering, CSIE, WRI World Congress on FLAGGED

作者： Songwen Pei Baifeng Wu Min Du Gang Chen Leandro A.J. Marzulo Felipe M.G. Franca School of Computer Science Fudan University Shanghai China Systems Engineering and Computer Science Program COPPE Rio de Janeiro Brazil

Speculative multithreading (SpMT) increases the performance by means of executing multiple threads speculatively to exploit thread-level parallelism. By combining software and hardware approaches, we have improved the capabilities of previous WaveScalar ISA on the basis of transactional memory system for the WaveCache Architecture. Threads are extracted at the course of static compiling, and speculatively executed as a thread-level transaction that is supported by extra hardware components, such as thread-context-table (TCT) and thread-memory-history (TMH). We have evaluated the SpMT WaveCache with 6 real benchmarks from SPEC, Mediabench and Mibench. On the whole, the SpMT WaveCache outperforms superscalar architecture ranging from 2times to 3times, and great performance gains are achieved over original WaveCache and transactional WaveCache as well.

关键词： Yarn Parallel processing Multithreading Hardware computer science computer architecture Instruction sets Out of order program processors Protocols

来源：评论

学校读者我要写书评

暂无评论

A massively parallel hardware architecture for ray-tracing

引用

International Journal of High Performance systems Architecture 2009年第1期2卷 26-34页

作者： Nery, A.S. Nedjah, N. França, F.M.G. Computer Architecture and Microelectronics Laboratory Systems Engineering and Computer Science Program COPPE P.O. Box 68511 21941-972 Rio de Janeiro Brazil Department of Electronics Engineering and Telecommunications Faculty of Engineering Universidade do Estado do Rio de Janeiro Rua Sao Francisco Xavier 524 Sala 5145-F Maracana 20.550-900 Rio de Janeiro RJ Brazil Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Department of Electronics Engineering and Telecommunications Faculty of Engineering State University of Rio de Janeiro Brazil Brazil

Real time performance of non-interactive rendering of three-dimensional scenes is usually unachievable. Ray tracing is one of the methods used for rendering such scenes. The performance achieved by a sequential software-based implementation of ray tracing is far from satisfactory. In contrast, many parallel implementations of ray tracing have been enabling real time performance, as the underlying algorithm can be massively parallelised. Thus, it is expected that a custom parallel design in hardware is likely to achieve the acceptable performance standards. In this paper, we propose a hardware architecture, which we call GridRT, capable of dealing with the main desirable features of ray tracing, such as shadows and reflections effects, imposing low requirements in terms of silicon area while achieving acceptable performance in terms of rendering time. This architecture achieves is efficient yet compact as it explores the massive parallelism offered by the intrinsic structure of the algorithm. The design exploits the usage the spatial data structure of regular grids. Copyright © 2009 Inderscience Enterprises Ltd.

关键词： Ray tracing

来源：评论

学校读者我要写书评

暂无评论

Impact of region-based faults on the connectivity of wireless networks

Impact of region-based faults on the connectivity of wireles...

引用

Annual Allerton Conference on Communication, Control, and Computing

作者： Arunabha Sen Sujogya Banerjee Pavel Ghosh Shahrzad Shirazipourazad Computer Science and Engineering Program School of Computing Informatics and Decision Systems Engineering Arizona State University Tempe AZ USA

ISBN: (纸本)9781424458707

The last few years have seen considerable interest in the wireless networking research community in analyzing the connectivity of wireless ad-hoc networks formed by a set of nodes distributed in a two dimensional plane (deployment area) with a (i) uniform probability density function and (ii) uniform transmission range. Although several important and interesting results are known in this domain, most of the connectivity studies consider a fault-free scenario where all nodes are available for network formation and do not consider failures among nodes caused by one reason or another. In very few studies where faults are considered, they are usually considered to be random in nature, i.e., the probability of a node failing is independent of its location in the deployment area. However, such fault scenario is inadequate to capture many realistic situations where the faulty nodes are spatially correlated. This is particularly true in combat environment where an enemy bomb can destroy a subset of nodes confined to a region. In this paper we investigate the impact of region-based faults on the connectivity of wireless networks. Through analysis and simulation, we provide results relating the probability of a network being connected as transmission range and the size of fault-region are varied. If d min (G) denotes the minimum node degree of the network, we provide the analytical expression for P(d min (G) ¿ k), which represents the probability of the minimum node degree being at least k, for k = 1. Moreover, we compute P(¿(G) ¿ k), where ¿(G) represents the connectivity of the graph G formed by the distribution of nodes in the deployment area and examine the relationship between P(d min (G) ¿ k) and P(¿(G) ¿ k) when k = 1.

关键词： Wireless networks Distributed computing Weapons Analytical models computer science computer networks Informatics systems engineering and theory Ad hoc networks Probability density function

来源：评论

学校读者我要写书评

暂无评论

Comparison of threshold selection methods for microarray gene co-expression matrices

引用

BMC Research Notes 2009年第1期2卷 1-6页

作者： Borate, Bhavesh Chesler, Elissa Langston, Michael Saxton, Arnold Voy, Brynn Genome Science and Technology Program University of Tennessee Knoxville TN United States Department of Electrical Engineering and Computer Science University of Tennessee Knoxville TN United States Oak Ridge National Laboratory Systems Genetics Group Biosciences Division Oak Ridge TN United States Department of Animal Science University of Tennessee Knoxville TN United States

Background. Network and clustering analyses of microarray co-expression correlation data often require application of a threshold to discard small correlations, thus reducing computational demands and decreasing the number of uninformative correlations. This study investigated threshold selection in the context of combinatorial network analysis of transcriptome data. Findings. Six conceptually diverse methods - based on number of maximal cliques, correlation of control spots with expressed genes, top 1% of correlations, spectral graph clustering, Bonferroni correction of p-values, and statistical power - were used to estimate a correlation threshold for three time-series microarray datasets. The validity of thresholds was tested by comparison to thresholds derived from Gene Ontology information. Stability and reliability of the best methods were evaluated with block bootstrapping. Two threshold methods, number of maximal cliques and spectral graph, used information in the correlation matrix structure and performed well in terms of stability. Comparison to Gene Ontology found thresholds from number of maximal cliques extracted from a co-expression matrix were the most biologically valid. Approaches to improve both methods were suggested. Conclusion. Threshold selection approaches based on network structure of gene relationships gave thresholds with greater relevance to curated biological relationships than approaches based on statistical pair-wise relationships. © 2009 Saxton et al;licensee BioMed Central Ltd.

关键词： Spectral Cluster Maximal Clique Threshold Estimate Biological Relationship Spectral Graph

来源：评论

学校读者我要写书评

暂无评论

Porantim: An approach to support the combination and selection of Model-based Testing techniques

Porantim: An approach to support the combination and selecti...

引用

International Workshop on Automation of Software Test (AST)

作者： Arilo Claudio Dias Neto Guilherme Horta Travassos Systems Engineering and Computer Science Program-COPPE/UFRJ Federal University of Rio de Janeiro Rio de Janeiro Brazil

The technical literature regarding model-based testing (MBT) has several techniques with different characteristics and goals available to be applied in software projects. Besides the lack of information regarding these techniques, they could be applied together in a software project aiming at improving the testing coverage. However, this decision needs to be carefully analyzed to avoid loss of resources in a software project. Based on this scenario, this paper proposes an approach with the purpose of supporting the unique or combined selection of MBT techniques for a given software project considering two aspects: the adequacy level between MBT techniques and the software project characteristics and impact of more than one MBT technique in some testing process variables. At the end, preliminary results of an experimental evaluation are presented.

关键词： Software testing Automatic testing Software tools System testing Software quality programming Software systems Costs Context modeling systems engineering and theory

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：