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81.
82.
Wayne O’Brien Author Vitae 《Journal of Systems and Software》2008,81(11):1997-2013
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. 相似文献
83.
Two parallel block tridiagonalization algorithms and implementations for dense real symmetric matrices are presented. Block tridiagonalization is a critical pre-processing step for the block tridiagonal divide-and-conquer algorithm for computing eigensystems and is useful for many algorithms desiring the efficiencies of block structure in matrices. For an “effectively” sparse matrix, which frequently results from applications with strong locality properties, a heuristic parallel algorithm is used to transform it into a block tridiagonal matrix such that the eigenvalue errors remain bounded by some prescribed accuracy tolerance. For a dense matrix without any usable structure, orthogonal transformations are used to reduce it to block tridiagonal form using mostly level 3 BLAS operations. Numerical experiments show that block tridiagonal structure obtained from this algorithm directly affects the computational complexity of the parallel block tridiagonal divide-and-conquer eigensolver. Reduction to block tridiagonal form provides significantly lower execution times, as well as memory traffic and communication cost, over the traditional reduction to tridiagonal form for eigensystem computations. 相似文献
84.
Infonorma is a multi-agent system that provides its users with recommendations of legal normative instruments they might be
interested in. The Filter agent of Infonorma classifies normative instruments represented as Semantic Web documents into legal
branches and performs content-based similarity analysis. This agent, as well as the entire Infonorma system, was modeled under
the guidelines of MAAEM, a software development methodology for multi-agent application engineering. This article describes
the Infonorma requirements specification, the architectural design solution for those requirements, the detailed design of
the Filter agent and the implementation model of Infonorma, according to the guidelines of the MAAEM methodology. 相似文献
85.
Yolanda Blanco-Fernndez Jos J. Pazos-Arias Alberto Gil-Solla Manuel Ramos-Cabrer Martín Lpez-Nores Jorge García-Duque Ana Fernndez-Vilas Rebeca P. Díaz-Redondo Jesús Bermejo-Muoz 《Knowledge》2008,21(4):305-320
Recommender systems arose with the goal of helping users search in overloaded information domains (like e-commerce, e-learning or Digital TV). These tools automatically select items (commercial products, educational courses, TV programs, etc.) that may be appealing to each user taking into account his/her personal preferences. The personalization strategies used to compare these preferences with the available items suffer from well-known deficiencies that reduce the quality of the recommendations. Most of the limitations arise from using syntactic matching techniques because they miss a lot of useful knowledge during the recommendation process. In this paper, we propose a personalization strategy that overcomes these drawbacks by applying inference techniques borrowed from the Semantic Web. Our approach reasons about the semantics of items and user preferences to discover complex associations between them. These semantic associations provide additional knowledge about the user preferences, and permit the recommender system to compare them with the available items in a more effective way. The proposed strategy is flexible enough to be applied in many recommender systems, regardless of their application domain. Here, we illustrate its use in AVATAR, a tool that selects appealing audiovisual programs from among the myriad available in Digital TV. 相似文献
86.
在快速的城市化进程中,遥感技术可以为城市土地利用变化提供直观、准确、同步的信息。本体是对概念化的明确描述和说明,更接近于认知模型,易于理解和共享;同时又能以计算机可操作的形式化语言明确表达目标领域的概念体系及其蕴含的语义。因此,在分析和借鉴现有相关研究的基础上,将本体、语义思想引入到遥感影像表达,建立了基于本体的城市遥感影像解译应用语义模型和解译框架,应用此框架将有助于提高城市遥感影像解译的精度与效率,对推动遥感技术在城市相关领域中的应用有着积极的意义。 相似文献
87.
主题划分是多主题文档自动摘要中的一个重要问题,提出了一种以网页结构为指导,利用页面对应DOM树中节点的自然分割功能以及相邻边界节点语义相似度的比较进行网页主题划分的方法.实验结果表明该方法具有较高的划分准确率,在此基础上抽取的网页摘要可显著增加文摘内容对原文的覆盖率、有效解决Web文档摘要分布不平衡问题. 相似文献
88.
89.
基于DSP的3DES加密系统的设计与实现 总被引:2,自引:1,他引:1
针对目前通用计算机实现的加密算法速度有限,而专用加密芯片的开发成本较高、开发周期相对较长的现状,采用数字信号处理器(DSP)设计了一种新型的加密系统;该系统采用TI公司高速浮点型DSP芯片TMS320C6713实现了3DES(Triple Data EncryptionStandard)加密算法;并采用CY7C68001 USB2.0接口芯片完成了DSP与PC的通讯;实验结果表明,该加密系统能高速可靠地运行,在该系统的基础上可以扩展成实时数据加密系统。 相似文献
90.
John Strassner Sven van der Meer Declan O’Sullivan Simon Dobson 《Journal of Network and Systems Management》2009,17(3):255-284
The purpose of autonomic networking is to manage the business and technical complexity of networked components and systems.
However, existing network management data has no link to business concepts. This makes it very difficult to ensure that services
offered by the network are meeting business objectives. This paper describes a novel context-aware policy model that uses
a combination of modeled and ontological data to determine the current context, which policies are applicable to that context,
and what services and resources should be offered to which users and applications.
John Strassner is the director of autonomic research in the Telecommunications Systems & Software Group in Waterford Institute of Technology, and a Visiting Professor at POSTECH. His research interests are in autonomic systems, policy based management, machine learning, and semantic reasoning. He is the Chairman of the Autonomic Communications Forum, and the past chair of the TMF’s NGOSS SID, metamodel and policy working groups. He has authored two books, written chapters for five other books, and co-edited five journals on network and service management and autonomics. John is the recipient of the Daniel A. Stokesbury memorial award for excellence in network management, and has authored 211 refereed journal papers and publications. Sven van der Meer received his M.Sc in computer science and his Dr.-Ing. from Technical University Berlin (TUB), Germany, in 1996 and 2002. Since November 2002, Sven has been a research fellow at the Telecommunications Software & Systems Group at the Waterford Institute of Technology. Since October 2004 he is Senior Investigator of the Competence Centre for Communication Infrastructure Management at TSSG, involved in the Architecture and Information Modelling teams in the TMF, and has served as editor for Technological Neutral Architecture and Contracts specifications within the TM Forum. Declan O’Sullivan is the director of the Knowledge and Data Engineering (KDEG) research group in Trinity College Dublin (TCD). His research interests are in the use of semantic-driven approaches for network and service management, in particular to enable semantic interoperability. He is currently a Principal Investigator in the SFI funded research project investigating Federated Autonomic Management Environments (FAME). O’Sullivan has a Ph.D. and a M.Sc in computer science from TCD. Simon Dobson is a co-founder of the Systems Research Group at UCD Dublin. His research centers around adaptive pervasive computing and novel programming techniques. He is on the editorial boards of the Journal of Network and Systems Management and the International Journal of Autonomous and Adaptive Communications Systems, and participates in a number of EU strategic workshops and working groups. He is National Director and vice-president of the European Research Consortium for Informatics and Mathematics, a board member of the Autonomic Communication Forum, and a member of the IBEC/ICT Ireland standing committee on academic/industrial research and development. He holds a BSc and DPhil in computer science, is a Chartered Fellow of the British Computer Society, a Chartered Engineer, and member of the IEEE and ACM. 相似文献
Simon DobsonEmail: |
John Strassner is the director of autonomic research in the Telecommunications Systems & Software Group in Waterford Institute of Technology, and a Visiting Professor at POSTECH. His research interests are in autonomic systems, policy based management, machine learning, and semantic reasoning. He is the Chairman of the Autonomic Communications Forum, and the past chair of the TMF’s NGOSS SID, metamodel and policy working groups. He has authored two books, written chapters for five other books, and co-edited five journals on network and service management and autonomics. John is the recipient of the Daniel A. Stokesbury memorial award for excellence in network management, and has authored 211 refereed journal papers and publications. Sven van der Meer received his M.Sc in computer science and his Dr.-Ing. from Technical University Berlin (TUB), Germany, in 1996 and 2002. Since November 2002, Sven has been a research fellow at the Telecommunications Software & Systems Group at the Waterford Institute of Technology. Since October 2004 he is Senior Investigator of the Competence Centre for Communication Infrastructure Management at TSSG, involved in the Architecture and Information Modelling teams in the TMF, and has served as editor for Technological Neutral Architecture and Contracts specifications within the TM Forum. Declan O’Sullivan is the director of the Knowledge and Data Engineering (KDEG) research group in Trinity College Dublin (TCD). His research interests are in the use of semantic-driven approaches for network and service management, in particular to enable semantic interoperability. He is currently a Principal Investigator in the SFI funded research project investigating Federated Autonomic Management Environments (FAME). O’Sullivan has a Ph.D. and a M.Sc in computer science from TCD. Simon Dobson is a co-founder of the Systems Research Group at UCD Dublin. His research centers around adaptive pervasive computing and novel programming techniques. He is on the editorial boards of the Journal of Network and Systems Management and the International Journal of Autonomous and Adaptive Communications Systems, and participates in a number of EU strategic workshops and working groups. He is National Director and vice-president of the European Research Consortium for Informatics and Mathematics, a board member of the Autonomic Communication Forum, and a member of the IBEC/ICT Ireland standing committee on academic/industrial research and development. He holds a BSc and DPhil in computer science, is a Chartered Fellow of the British Computer Society, a Chartered Engineer, and member of the IEEE and ACM. 相似文献