普适服务综述

随着技术和市场的发展,电信网和互联网正在走向融合,形成一体化网络,提供的服务也将逐步趋同。普适服务融合了各方面对未来服务的需求和期望,成为超3G、下一代网络（NGN）、下二代互联网（NGI）等研究领域的热点问题。普适服务的概念起源于普适计算和超3G领域,其特征包括普适性、移动性、透明性、质量可控性、个性化、自适应性、主动性、安全性、易用性、多样性、快捷性。3GPP、OMA等标准化组织以及欧盟的超3G研究项目都针对普适服务的不同特征进行了研究。当前普适服务的研究热点包括上下文感知、业务使能等技术。     

Service Discovery in Agent-Based Pervasive Computing Environments

Directory based service discovery mechanisms are unsuitable for ad-hoc m-commerce environments. Working towards finding an alternate mechanism, we developed Allia: a peer-to-peer caching based and policy-driven agent-service discovery framework that facilitates cross-platform service discovery in ad-hoc environments. Our approach achieves a high degree of flexibility in adapting itself to changes in ad-hoc environments and is devoid of common problems associated with structured compound formation in mobile commerce environments. Device capabilities and limitations, user preferences regarding device usage, application specifics with respect to mobile commerce are factors that our framework adapts to. We have described our initial implementation of Allia over ThinkPads and iPAQs by extending the LEAP Agent Platform and using Bluetooth as the underlying network protocol. In addition, we evaluated Allia's performance by running simulations of our protocol in Glomosim simulator. We also compared our framework against a structured compound-based architecture.     

络明网络为城域网注入新活力

MSTT随着以数据业务为主的非话音业务的迅猛发展,传统的基于SDH的城域传送网面临着许多问题和挑战,比如不能有效地传送和处理新兴的多种业务、缺乏带宽动态调配能力、资源利用率低、网络扩展性差、业务开通速度慢。以太网技术则由于缺乏电信级的QoS、网络快速保护/恢复及完善的     

QoS-Aware Service Selection Algorithms for Pervasive Service Composition in Mobile Wireless Environments

The successful application of pervasive services running in mobile wireless networks and devices relies on its ability to provide efficient and cost-effective QoS (Quality of Service) support. This paper proposes a comprehensive QoS model specifically for pervasive services. It considers not only user-perceived factors but also mobile wireless network characteristics. The corresponding formula to calculate each QoS criterion is also devised. In particular, this paper formulates the QoS-aware service selection problem for pervasive service composition and proposes some solutions to the problem, i.e., global-search-based LOSSA (local optimal service selection algorithm) and limited broadcast based LOSSA-k. The evaluation results of the algorithms have shown the effectiveness of the QoS model and the efficiency of the proposed LOSSAs.     

基于ASM的普适环境下的服务动态组合

在综合研究已有的服务组合的各种方案的基础上,采用层次结构的服务组合框架,同时利用回溯树进行服务的动态组合,最后用ASM建立一个普适环境下服务动态组合的基础模型并对其进行精化,同时通过CoreASM对该模型进行模拟执行验证.     

Piecewise Network Awareness Service for Wireless/Mobile Pervasive Computing

This paper presents a piecewise framework for network awareness service (NAS) for wireless/mobile pervasive computing. We investigate how piecewise consideration of wired and wireless elements of the framework architecture benefits service advertisement and discovery and network-awareness techniques. We also discuss scalability of the NAS framework with respect to platform computing capabilities. The framework is suitable for a wide range of computing devices, from powerful ones with multi-tasking operating systems (OS) to small ones with lightweight OS. Case studies applying the NAS framework to sensor monitoring in home networks and data streaming in pervasive multimedia computing are presented. The analytical results on the performance of the NAS framework in these case studies show that it has significant advantages over traditional network-awareness frameworks in terms of reducing wireless bandwidth consumption and saving battery energy of mobile devices.     

A User-Centric Approach for Personalized Service Provisioning in Pervasive Environments

The vision of pervasive environments is being realized more than ever with the proliferation of services and computing resources located in our surrounding environments. Identifying those services that deserve the attention of the user is becoming an increasingly-challenging task. In this paper, we present an adaptive multi-criteria decision making mechanism for recommending relevant services to the mobile user. In this context, “Relevance” is determined based on a user-centric approach that combines both the reputation of the service, the user’s current context, the user’s profile, as well as a record of the history of recommendations. Our decision making mechanism is adaptive in the sense that it is able to cope with users’ contexts that are changing and drifts in the users’ interests, while it simultaneously can track the reputations of services, and suppress repetitive notifications based on the history of the recommendations. The paper also includes some brief but comprehensive results concerning the task of tracking service reputations by analyzing and comprehending Word-of-Mouth communications, as well as by suppressing repetitive notifications. We believe that our architecture presents a significant contribution towards realizing intelligent and personalized service provisioning in pervasive environments.     

普适计算在企业信息查询服务的应用

在服务器端构建Wireless Application Protocol（WAP）网站，选择中国移动通信提供的cmwap服务，将移动电话通过无线网和Internet网互连，可设计浏览和查询WAP服务器信息的平台。文章提交了平台环境配置、系统结构、数据库结构，应用程序中数据库接口设计，通信设备的应用等主要技术。并以山花地毯公司电子商务为背景运行该平台，实现了客户对地毯图案的服务请求与公司电话簿查询功能。     

A Secure Infrastructure for Service Discovery and Access in Pervasive Computing

Security is paramount to the success of pervasive computing environments. The system presented in this paper provides a communications and security infrastructure that goes far in advancing the goal of anywhere-anytime computing. Our work securely enables clients to access and utilize services in heterogeneous networks. We provide a service registration and discovery mechanism implemented through a hierarchy of service management. The system is built upon a simplified Public Key Infrastructure that provides for authentication, non-repudiation, anti-playback, and access control. Smartcards are used as secure containers for digital certificates. The system is implemented in Java and we use Extensible Markup Language as the sole medium for communications and data exchange. Currently, we are solely dependent on a base set of access rights for our distributed trust model however, we are expanding the model to include the delegation of rights based upon a predefined policy. In our proposed expansion, instead of exclusively relying on predefined access rights, we have developed a flexible representation of trust information, in Prolog, that can model permissions, obligations, entitlements, and prohibitions. In this paper, we present the implementation of our system and describe the modifications to the design that are required to further enhance distributed trust. Our implementation is applicable to any distributed service infrastructure, whether the infrastructure is wired, mobile, or ad hoc.     

Pervasive Access to MRI Bias Artifact Suppression Service on a Grid

Bias artifact corrupts MRIs in such a way that the image is afflicted by illumination variations. Some of the authors proposed the exponential entropy-driven homomorphic unsharp masking (E²D-HUM) algorithm that corrects this artifact without any a priori hypothesis about the tissues or the MRI modality. Moreover, E²D-HUM does not care about the body part under examination and does not require any particular training task. People who want to use this algorithm, which is Matlab-based, have to set their own computers in order to execute it. Furthermore, they have to be Matlab-skilled to exploit all the features of the algorithm. In this paper, we propose to make such algorithm available as a service on a grid infrastructure, so that people can use it almost from everywhere, in a pervasive fashion, by means of a suitable user interface running on smartphones. The proposed solution allows physicians to use the E²D-HUM algorithm (or any other kind of algorithm, given that it is available as a service on the grid), being it remotely executed somewhere in the grid, and the results are sent back to the user's device. This way, physicians do not need to be aware of how to use Matlab to process their images. The pervasive service provision for medical image enhancement is presented, along with some experimental results obtained using smartphones connected to an existing Globus-based grid infrastructure.     

基于抽象状态机的普适服务组合分析与验证

提出了一个普适环境下服务组合的框架,使用抽象状态机对服务的行为进行不同精化层级的形式化描述,然后利用 CoreASM 这一模型检测工具对服务组合进行模拟执行验证,从而验证服务组合的正确性.最后给出了一个运用此方法进行服务组合验证的典型应用场景.     

Pervasive Home Environments

For decades, technologists have been promising the intelligent house. The vision is usually portrayed as a house filled with technology which will do the dweller's bidding and take all domestic drudgery out of their lives. The truly intelligent house is still some way off, but the emergence of broadband, availability of faster, smaller and ever cheaper computing equipment and a variety of wired and wireless network technologies are enabling technologies that bring this vision closer to reality. These technology trends lead to the concept that computing and other smart devices will become pervasive, fully networked and disappear into the infrastructure of the home. People will carry out their tasks unaware of the complexity of the infrastructure that supports their activities in much the same way as people today use mains electricity.This paper introduces these concepts and discusses the technological challenges to be overcome. We present our vision of the pervasive home environment where inhabitants can focus on tasks rather than the technology: I need to create X and send it to Y rather than I need to use this computer and this application which needs access to service A and resource B. Although this sounds simple, the environment needs to understand who I is, and who or what Y is. Appropriate permissions must be in place and resources allocated, if available. The most appropriate interface for the task and user must be determined.The pervasive, intelligent home will make available new ways to access and share information. It will herald new services, such as care and support of people in the home, entertainment, educational and security services. The final part of the paper discusses the commercial opportunities and challenges which must be met, not least the need for industry to agree on open standards and interfaces.     

注F+加固CMOS/SOI材料的抗辐射研究

向SIMOX材料的SiO2埋层或Si/SiO2界面注入170 keV F+,进而制成CMOS/SOI材料,采用60Co g 辐射器辐照并测量材料的I-V特性。结果表明:向CMOS/SOI材料埋层注入F+离子,能提高CMOS/SOI材料的抗电离辐照性能。而且,注入F+的剂量为11015cm2时,材料的抗辐照能力较强。这对制作应用于电离辐射环境的COMS/SOI器件极其有益。     

A Survey of Pervasive Services

With the technological advances and market development, telecommunications networks and the Internet are converging into one universal network; meanwhile, the services provided by these two kinds of networks are integrating. Pervasive services will meet demands and expectations from all aspects. The topic has become a favorite for research in Beyond Third Generation (B3G), Next Generation Network (NGN) and Next Generation Internet (NGI) fields. The concept of the pervasive services comes from pervasive computation and B3G. Their features include pervasiveness, mobility, transparency, QoS-guarantee, customization, adaptiveness, push, security, easiness, variety and time-to-market. 3GPP, OMA and the B3G research program of the European Union (EU) have conducted a lot of research work about the different features of pervasive services. The current hot topics in the pervasive services research include context awareness and service enabling.     

Scale-Free Topology for Pervasive Networks

Scale-free graphs and their properties have attracted considerable interest over the last 4–5 years, after it was discovered that many natural and artificial networks belong to this category. However, the so-called preferential attachment rule, whereby scale-free topology can most easily be obtained, relies on newcomers having a global knowledge of the existing connectivity profile. Moreover, the addition of new nodes is usually assumed to be sequential and monotonous (one new node joins the network between two consecutive updates of the global connectivity profile, throughout the growth process). This is incompatible with the requirements of pervasive, ad hoc systems, where it cannot be guaranteed that either of these conditions applies.In this paper, we investigate methods to overcome this difficulty by devising realistic connection protocols that would allow approximating scale-free topology on the sole basis of local information exchange. We argue that successful implementation of our findings could have important implications for pervasive computing environments, as scale-free topology has very desirable features in terms of efficiency and robustness.     

普适计算与泛在网络

本文简要描述了普适计算的概念及普适计算的研究体系;泛在网络的概念及与普适计算的关系.简要介绍了移动泛在网络发展的愿景.在此基础上,较详细地讨论了我国专家们在泛在网络研究领域中提出的环境感知泛在网络(AUN)的概念和框架结构.     

Intelligent and Pervasive Multimedia Systems

Recent advances in pervasive computing and the proliferation of multimedia-capable devices have stimulated the development of intelligent and pervasive multimedia applications. This special issue provides excellent coverage of this area, including interactive multimedia education, quality control and personalization of multimedia services, peer-to-peer multimedia streaming, mobile TV, and VoIP systems.     

动态测量的普适计算

传感器测量物体属性并由数字系统对测量的原始数据进行处理获得需要的信息。在动态测量中存在数据量大及严重的随机性等特点。测量数据的处理方法将对测量系统的性能产生重要影响。现在,计算机和嵌入式系统在刺量系统中获得广泛应用,则普适计算模式成为具有优势的选择。基于热量测量系统,给出了拓扑原理及应用分析。特别是在动态测量的测量数据处理中,普适计算性能优越。