NGN网络中QOS模型研究

NGN是电信网络变革的必然方向，特别是随着NGN试验与商用网络规模的不断扩大，对NGN所提供综合业务的QoS（Quality of Service）需求将会越来越突出。在这样的背景下．NGN的QoS研究具有重要的理论价值和实用意义，并且已经成为业界的研究热点之一．本论文深入研究几种NGN中常用的QoS模型。     

下一代网络NGN

下一代计算机网络NGN(NextGenerationNetwork)的研究、探讨已经成为当前的潮流,NGN是目前电信、互联网运营商和设备厂商都在讨论的热点技术,也是国外许多标准化组织和论坛的研究工作重点。文章介绍了NGN的由来、定义、主要特点、体系结构、协议、核心技术、进展情况、应用前景等。     

国际NGN标准框架基本形成

在明确NGN的研究方向和重点研究内容的基础上，从NGN的框架结构、业务要求、功能要求、移动性管理、服务质量等方面对NGN标准的最新进展情况作了概括介绍，并对可管理的IP网络架构进行了描述。     

走向融合的NGN

下一代网络(NGN)是目前运营商和设备厂商都在讨论的热点技术,国内外许多网络运营商都在探讨,并正在或考虑建试验网进行更深入的研究。本文主要介绍了NGN的特点,体系结构、以及有关NGN的标准进展等。     

NGN网络的发展方向及其面临的主要问题

文章论述了NGN网络的发展方向、NGN网络在国内外的研究发展状况，并对NGN网络所面临的主要问题进行了讨论分析。     

NGN技术——网络发展的未来趋势

NGN作为通信网络建设的下一代技术,是近年来通信业关注的焦点。各大电信运营商都将NGN作为降低运营成本、开展新业务、提升ARPU值、全面提升差异化竞争力的砝码。本文介绍了NGN的产生背景和概念,提出NGN的核心技术和业务。     

浅谈NGN软交换技术的应用与发展

NGN软交换技术是网络的核心技术,能够提供声音、视频、多媒体业务的综合技术,本文主要对NGN软交换技术的概念、NGN软交换技术的现状以及NGN软交换技术的发展趋势做了阐述。期望为NGN软交换技术的健康发展提供有利帮助。     

关注NGN商用化进程中的5W问题

NGN一直是业界普遍关注的热点与焦点，也一度被认为是高不可攀的空中楼阁。2004年以前，人们更多的是关注NGN定义和标准；而2004年以后．软交换网开始大举商用，数个NGN实验网并举，NGN设备也日趋成熟，运营商开始解决软交换网商用时的操作、维护、运营和管理问题。2005年注定成为NGN的拐点。随着软交换体系的完善以及相关设备的成熟，越来越多的运营商为了应对业务需求多样化的挑战．将在2005年开始大规模部署NGN的商用网络。     

NGN技术发展探讨

NGN作为通信网络建设的下一代技术,是近年来通信业关注的焦点。各大电信运营商都将NGN作为降低运营成本、开展新业务、全面提升差异化竞争力的砝码。文章着重介绍了NGN的概念、技术优势和体系结构,最后总结了NGN网络的未来发展趋势。     

以用户为核心的网络融合

ITU-T对NGN下的定义：“NGN是基于分组的网络，能够提供电信业务；利用多种宽带能力和QoS保证的传送技术；其业务相关功能与其传送技术相独立。NGN使用户可以自由接入到不同的业务提供商；NGN支持通用移动性”。由此看来，NGN是一种业务驱动型网络。业务和呼叫控制完全分离、呼叫控制和承载完全分离，使业务独立于网络。     

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。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

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.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.