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阐述了家庭DigitalHubbub的功能要求;设计并制作了家庭DigitalHubbub;给出了方案的硬件和软件设计。提出了基于家庭DigitalHubbub构造分布式多媒体服务器系统的方法,提出了分布式多媒体服务系统的硬件模型和系统的软件。 相似文献
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QoS研究的理论框架以及研究现状(1) 总被引:4,自引:1,他引:4
白成林 《计算机工程与应用》2002,38(24):154-160,164
文章从分布式多媒体应用端到端QoS控制的角度,首先介绍了QoS的定义和标准,而后分阶段、分层次地阐述了QoS的控制和管理框架,包括QoS控制机制的设计原则、QoS的描述、QoS控制和管理机制以及QoS的控制层次。 相似文献
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Web QoS是当前Web计算中的重要研完内容,用于解决Web计算环境中端到端QoS保证问题。本文提出一种支持QoS的Web服务器集群系统方案以及实现技术,整个系统由支持QoS的集群交换机和Web服务器集群两级结构组成,通过集群交换机和Web服务器的协同工作,实现优先转发与优先服务相结合的分布式QoS保证体系,充分满足Web用户的服务质量需求。通过系统测试,原型系统的性能指标达到了设计要求。 相似文献
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家庭网络多媒体正成为网络主要推动力,而家庭网关成为家庭网络的核心设备。该文完成了基于Lexra网络处理器家庭网关设计,并讨论了网关QoS设计原则,在路由和队列调度层面上实现了QoS保证,并在实际项目中验证了QoS性能。 相似文献
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朱强 《计算机工程与应用》2005,41(29):163-166
在分布式视频点播系统中,由于不同视频服务器到代理服务器之间的网络QoS状况可能存在较大的差异,因此多媒体代理服务器必须引入有效的服务器选择算法。文章主要讨论所提出的在多服务器模型下基于增益模型的服务器选择算法;通过仿真实验测试其性能、与其他算法进行比较;并分析此算法对环境参数变化的适应性。 相似文献
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IMS(IP多媒体子系统)给客户带来丰富的多媒体体验的同时,也对服务质量(QoS)管理提出了更高的要求,即针对不同用户定制的不同服务,网络运营商应该制定差异化的策略进行QoS管理。3GPP定义了基于策略的QoS管理框架,但这个框架只是逻辑上的架构,没有定义具体物理实施的方案。对基于策略QoS管理模型进行了分析,在参照3GPP定义的标准基础上,提出了一种管理模型的实现方案,设计并实现了该模型中两个关键服务器策略决策服务器(PDF)和策略执行服务器(PEP)。经过测试,两个服务器能互相配合,正确完成查询策略信息,做出策略决策,执行带宽请求预留、QoS等级协商功能,为网络运营商提供了参考。 相似文献
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1 引言近年来,随着分布式多媒体组应用的兴起,多媒体组通信机制开始得到人们的关注。组通信一直是一个比较重要的研究领域。对于传统的分布式组应用,已经取得了很多成果。但是,由于分布式多媒体组应用通常具有较高的QoS需求,因此传统分布式组应用领域的很多成果不能直接应用。为此,本文作者提出一种基于服务质量的多媒体组通信机制—QoS受控型组 相似文献
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视频点播等多媒体应用一般都有较高的QoS要求,而现有的多数网络系统并不提供QoS保障,这就要求分布式多媒体系统提供强有力的QoS管理机制以满足多媒体应用的需要。文章对视频点播系统中QoS管理的框架结构及通用对象模型进行了研究,并提出了相应解决方案。 相似文献
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基于中间件的QoS管理模型的研究与应用 总被引:2,自引:0,他引:2
随着多媒体处理技术和高速网络技术的发展,分布式多媒体应用得到长足发展,分布式多媒体中的实时音频、视频应用的一个关键问题就是多媒体的QoS管理和控制问题。该文提出了一种应用层的基于中间件的QoS管理模型,研究端系统的QoS和资源管理。该框架允许用户和应用对QoS管理策略和适应性调整策略进行应用级的定制。文章在资源管理中提出了通用资源接口及其具体实现方法。并从应用层的角度,结合国内外的研究成果,在网络层和操作系统之上提出通用接口应具备的功能,以及如何与QoS管理器协调工作,及其简单实现。 相似文献
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S. Shaw 《Journal of Computer Assisted Learning》1993,9(2):93-99
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. 相似文献
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European Community policy and the market 总被引:1,自引:0,他引:1
C. Lloyd 《Journal of Computer Assisted Learning》1993,9(2):86-91
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. 相似文献
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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。 相似文献
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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
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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. 相似文献
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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 相似文献
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David Poole 《Computational Intelligence》1989,5(2):97-110
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. 相似文献
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Watts S. Humphrey 《Annals of Software Engineering》2002,14(1-4):39-72
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. 相似文献
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基于复小波噪声方差显著修正的SAR图像去噪 总被引:4,自引:1,他引:3
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。 相似文献
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R. NOSS 《Journal of Computer Assisted Learning》1987,3(1):2-12
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. 相似文献