The Pervasive 2007 Workshops

Pervasive 2007 hosted an incredible full day of workshops before the main conference. One-hundred twenty enthusiastic participants in eight great workshops discussed experiences and ideas on particular aspects of pervasive computing with like-minded researchers and practitioners. The variety of projects presented demonstrated how truly interdisciplinary the Pervasive conference has become.     

面向用户的普适计算系统可用性度量模型

普适计算模式追求随时随地的计算境界,对相关可用性管理提出了很高的要求。现有研究大多基于定性的角度研究普适计算系统的可用性问题,本文尝试给出定量的可用性度量模型和分析。普适计算系统可用性具有典型的面向用户特点,为刻画用户行为需要引入具有非指数分布性质的模型状态,并且需要考虑用户态与系统态关联分析时的复杂情况。传统的连续时间马尔可夫链和半马尔可夫过程都不能很好地对以上情况给与分析。鉴于此,本文提出了一种基于马尔可夫重生过程(MRGP)的普适计算系统可用性度量方法。首先建立具有双扩展特点的用户模型,基于此构建了普适计算系统可用性度量的MRGP模型,对可用性进行了随机过程分析,给出了对应瞬态和稳态行为的度量方法,结合普适计算模式的特点定义了普适计算系统请求可用性度量。最后进行了数值分析,评价了用户和系统参数等因素对普适计算系统可用性度量的影响。     

It's all about the service

Managed rollouts of electronic data interchange (EDI) oftenmean the imposition of cost and inconvenience on companies withlow market power by trading partners with large market power.This damages customer and supplier relationships. But it doesn'thave to be that way.     

IEEE Pervasive Computing 2007 Annual Index, Volume 6

IEEE Pervasive Computing's 2007 annual index includes a complete author index and a list of all articles and departments published this year. The PDF file is free, and all titles link to their Computer Society Digital Library abstracts. Pervasive Computing subscribers can also access the HTML file, which includes internal links for coauthors.     

It's about Time: Analytical Time Periodization

This paper presents a novel approach to the problem of time periodization, which involves dividing the time span of a complex dynamic phenomenon into periods that enclose different relatively stable states or development trends. The challenge lies in finding such a division of the time that takes into account diverse behaviours of multiple components of the phenomenon while being simple and easy to interpret. Despite the importance of this problem, it has not received sufficient attention in the fields of visual analytics and data science. We use a real-world example from aviation and an additional usage scenario on analysing mobility trends during the COVID-19 pandemic to develop and test an analytical workflow that combines computational and interactive visual techniques. We highlight the differences between the two cases and show how they affect the use of different techniques. Through our investigation of possible variations in the time periodization problem, we discuss the potential of our approach to be used in various applications. Our contributions include defining and investigating an earlier neglected problem type, developing a practical and reproducible approach to solving problems of this type, and uncovering potential for formalization and development of computational methods.     

主题兴趣度提取方法及其在用户兴趣模型中的应用研究

用户兴趣模型能够极大的提高用户利用互联网的效率。目前的兴趣模型表示方法大多只包含不同兴趣主题的内容信息,而没有对不同兴趣主题之间进行一定的重要程度区分。在传统的VSM(Vector Space Model)向量中引入了兴趣度因子,进一步提出了主题兴趣度的概念并对主题兴趣度的提取方法进行了详细描述。实验结果表明,通过该方法建立的兴趣模型,能够较好的区分用户的不同兴趣,更加符合实际。     

普适计算：人本计算

普适计算强调以人为本的计算思想，它主张计算应迎合人的习性，自主地与使用者产生互动，使用户能集中精力于所要完成的任务。在普适计算环境下，计算将融入到人们的日常生活之中，使人们能够随时随地无妨碍地获得计算和信息服务。综述了普适计算的发展历史、现状和研究热点，分析和讨论了普适计算的概念和特性，最后对目前一些具有代表性的普适计算研究项目进行了简要的介绍和分析。     

PerCom 2004: Promoting the Pervasive Computing Paradigm

PerCom 2004's theme was the emergence of the pervasive computing and communications paradigm with the goal of providing computing and communication services all the time, everywhere. The featured research represented the advances in pervasive computing and communications, including wireless networks, mobile computing, distributed computing, and agent technologies that will help realize this goal.     

Public Pervasive Computing: Making the Invisible Visible

The increasing deployment of pervasive computing technologies in urban environments has inspired researchers to explore the intersections between physical, social, and digital domains. The multidisciplinary Just-for-Us project is developing a mobile Web service designed to facilitate new forms of interaction by adapting content to the user's physical and social context.     

It's about time: Signal recognition in staged models of protein translocation

During their synthesis, a large fraction of proteins are directed to the secretory pathway. There are several models that aim to distinguish between different destinations along this pathway; however, they rarely distinguish between known stages of this translocation process.This paper presents a translocation probability function which models the protein SRP-recruitment process—the first stage of the secretory pathway. It unifies groups of proteins with distinct final destinations, allowing more specific sorting to be done in due course, mirroring the hierarchical nature of secretory translocation.We apply conditional random fields to evaluate the prediction accuracy of a full sequence model. Introducing the translocation function improves substantially compared to a model based on properties that are relevant to the subsequent stages and final destinations only. For the discrimination of secretory, signal peptide (SP)-equipped proteins and non-secretory proteins a correlation coefficient of 0.98 is achieved—a level of performance that is only met by specialized SP predictors. Transmembrane proteins cause considerable confusion in signal peptide predictors, but fit naturally into our transparent design and reduce the performance of the translocation function only slightly.The proposed function and model assist efforts to uncover localization and function for the growing numbers of protein sequence data. Applying our model we estimate with high confidence that about 27% of the human and 29% of the mouse proteins are associated with the secretory pathway.     

组播服务用户控制机制综述

组播技术以其支持大规模的一对多、多对多通信的特点,成为目前网络通信领域研究的热点。然而其开放的通信机制在提供高效、便利的同时,也带来了一系列的安全问题。本文分析了组播模型的基本特性所带来的安全弱点。介绍了建立组播服务用户控制机制的必要性,详细阐述了组播服务用户控制机制中四个领域的研究内容：接收者访问控制、组播源访问控制、组播源鉴别和组内信息区分技术。随着组播服务逐步的商业化运行,建立一套完善的群组用户控制机制成为十分迫切的任务,并且有着广阔的应用前景。     

BTrust：普适计算环境下的信任管理

利用Beta概率密度函数建立起普适计算环境下各个设备间轻量级的信任管理模型BTrust。通过源实体对目标实体直接服务结果的观察计算出直接信任服务值,并结合第三方实体的推荐服务值计算出目标实体服务的总信任值。加入的推荐信任的计算,给予不同的第三方实体推荐服务信任值不同的权重。该模型建立起设备间的信任关系,提高了服务成功率,并运用过滤机制抵制恶意推荐。仿真结果表明,该模型同时解决了该环境下小型设备的资源受限问题。     

一种普及计算环境中的基础设施：PvCGrid

随着计算机技术的发展，人们希望能方便地享用计算能力和信息服务，但是由于计算设备的多样性和设备之间多传输协议的多样性，资源的描述、发现和使用方式的差异，资源之间协作缺乏统一的标准，造成了使用计算设备的障碍。该文提出了一种在普及计算环境中的基础设施——PvCGrid，实现了多种传输协议的管理、设备和服务的发现，提供了用户可定制的组合服务的功能，使得用户可以发现和使用网络中的资源，并且可以根据发现的资源，定制出更加复杂的应用，该基础设施为普及计算提供了互连互通、资源共享和协同服务的技术支持。     

智能手机:普适感知与应用

智能手机正在迅速成为个人计算和通讯的核心设备.得益于硬件技术的进步和移动互联网的普及,基于智能手机的感知手段日益丰富,可感知信息的维度不断增加,在健康、医疗、生活、交通、教育和娱乐等领域的应用层出不穷.该文从智能手机感知的硬件基础、智能手机可感知的信息和智能手机感知的应用3个层面对当前的研究进展进行阐述与分析,并对未来的研究趋势进行了展望.     

Pervasive 2004: A Viennese Treat

At the 2nd International Conference on Pervasive Computing, researchers and practitioners in all areas of pervasive and ubiquitous computing met in palatial surroundings to participate in workshops, technical presentations, and a doctoral colloquium.     

BTrust:普适计算环境下的信任管理

利用Beta概率密度函数建立起普适计算环境下各个设备间轻量级的信任管理模型BTrust。通过源实体对目标实体直接服务结果的观察计算出直接信任服务值,并结合第三方实体的推荐服务值计算出目标实体服务的总信任值。加入的推荐信任的计算,给予不同的第三方实体推荐服务信任值不同的权重。该模型建立起设备间的信任关系,提高了服务成功率,并运用过滤机制抵制恶意推荐。仿真结果表明,该模型同时解决了该环境下小型设备的资源受限问题。     

AnySpot: Pervasive Document Access and Sharing

The World Wide Web, wireless devices, and wireless networks have increased the opportunities for supporting pervasive document access and sharing. However, today's solutions remain spotty in their coverage for pervasive information needs. To address this, AynSpot is developed, a Web-service-based platform that seamlessly connects users to personal and shared documents wherever they go, meeting several key requirements of pervasive information access. This paper describes AnySpot's design principles and report our experience deploying it in a large, multinational organization.