Evaluating Pervasive and Ubiquitous Systems

Recognized evaluation strategies are essential to systematically advance a research field's state of the art. Pervasive and ubiquitous computing need such strategies to mature as a discipline and to enable researchers to objectively assess and compare new techniques' contributions. Researchers have shown that evaluating ubiquitous systems can be difficult, so approaches tend to be subjective, piecemeal, or both. To ensure that the validity and usability of proposed systems won't be compromised, researchers must reach consensus on a set of standard evaluation methods for ubiquitous systems. Otherwise, methods for scientifically testing and presenting state-of-the-art advances will remain unclear. In this article, the organizers from four different workshop series, each focused on this topic, summarize and discuss the main outcomes of these events.     

Designing with Care: The Future of Pervasive Healthcare

Humane care—which is an important design paradigm relevant for pervasive healthcare—means designing systems with care, keeping in mind both users and other stakeholders. Understanding human values is a key factor in creating any successful healthcare application and is essential to avoid dehumanizing and stigmatizing users. By considering human values, designers and developers can create pervasive healthcare applications that better fit users' needs and desires. The Designing with Care 09 workshop aimed to bring together researchers, designers, and practitioners to share their experiences with incorporating values into the design of pervasive healthcare systems and to help understand the sensitive issues involved in designing for healthcare. Based on the findings from the workshop, the present state of the art is discussed, and a research agenda is presented.     

普适环境室内定位系统研究

位置感知服务是普适计算的一类重要应用。在位置感知服务中,位置信息是关键的上下文之一。如何获取位置上下文,是位置感知服务中的关键点之一。基于不同的应用背景和服务,目前已经存在大量的定位系统。从室内定位的角度,研究了定位系统中的关键技术和方法,并对各种技术进行了分析比较;在分析现有普适环境下典型的室内定位系统基础上,提出了室内定位系统所面临的挑战。     

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。     

Multiple-Agent Perspectives in Reasoning About Situations for Context-Aware Pervasive Computing Systems

In open heterogeneous context-aware pervasive computing systems, suitable context models and reasoning approaches are necessary to enable collaboration and distributed reasoning among agents. This paper proposes, develops, and demonstrates the following: 1) a novel context model and reasoning approach developed with concepts from the state-space model, which describes context and situations as geometrical structures in a multidimensional space; and 2) a context algebra based on the model, which enables distributed reasoning by merging and partitioning context models that represent different perspectives of computing entities over the object of reasoning. We show how merging and reconciling different points of view over context enhances the outcomes of reasoning about the context. We develop and evaluate our proposed algebraic operators and reasoning approaches with cases using real sensors and with simulations. We embed agents and mobile agents with these modeling and reasoning capabilities, thus facilitating context-aware and adaptive mobile agents operating in open pervasive environments.     

基于DFL的主动数据库系统设计

基于 DFL,针对动态模糊数据的特点 ,给出动态模糊主动数据库系统的设计方法 ,其中包括 DF的数据库 ,DF事件代数等内容     

普适计算

上世纪90年代初,美国Weiser博士提出“普适计算”这一新概念,开始了人类向未来计算机时代探索的进程。本文首先回顾Xerox PARC的普适计算原创性研究,然后叙述普适计算的内涵及有关的计算机时代变迁。最后,我们简单介绍若干普适计算研究项目所提出的幻想和挑战。     

Designing Fuzzy-Rule-Based Systems Using Continuous Ant-Colony Optimization

This paper proposes the design of fuzzy-rule-based systems using continuous ant-colony optimization (RCACO). RCACO determines the number of fuzzy rules and optimizes all the free parameters in each fuzzy rule. It uses an online-rule-generation method to determine the number of rules and identify suitable initial parameters for the rules and then optimizes all the free parameters using continuous ant-colony optimization (ACO). In contrast to traditional ACO, which optimizes in the discrete domain, the RCACO optimizes parameters in the continuous domain and can achieve greater learning accuracy. In RCACO, the path of an ant is regarded as a combination of antecedent and consequent parameters from all the rules. A new path-selection method based on pheromone levels is proposed for initial-solution construction. The solution is modified by sampling from a Gaussian probability-density function and is then refined using the group best solution. Simulations on fuzzy control of three nonlinear plants are conducted to verify RCACO performance. Comparisons with other swarm intelligence and genetic algorithms demonstrate the advantages of RCACO.      

Designing Distributed Diagnosers for Complex Continuous Systems

Wear and tear from sustained operations cause systems to degrade and develop faults. Online fault diagnosis schemes are necessary to ensure safe operation and avoid catastrophic situations, but centralized diagnosis approaches have large memory and communication requirements, scale poorly, and create single points of failure. To overcome these problems, we propose an online, distributed, model-based diagnosis scheme for isolating abrupt faults in large continuous systems. This paper presents two algorithms for designing the local diagnosers and analyzes their time and space complexity. The first algorithm assumes the subsystem structure is known and constructs a local diagnoser for each subsystem. The second algorithm creates the partition structure and local diagnosers simultaneously. We demonstrate the effectiveness of our approach by applying it to the Advanced Water Recovery System developed at the NASA Johnson Space Center.     

CORBA设计中的性能分析

为了保持生命力,CORBA技术必须不断向前发展,而其性能在CORBA设计及应用中起着关键的作用.文中指出了现存CORBA在性能敏感型应用中的缺陷和造成CORBA性能低下的原因.从CORBA产品和CORBA应用开发者的角度出发,指出了一些提高CORBA性能的方法.首先对CORBA技术进行简单介绍,接着讨论CORBA的性能要求.最后,详细介绍影响CORBA性能的几个重要因素.所提出的性能优化方法对实际系统的开发具有一定的指导意义.     

CORBA设计中的性能分析

为了保持生命力，GORBA技术必须不断向前发展，而其性能在OORBA设计及应用中起着关键的作用。文中指出了现存GORBA在性能敏感型应用中的缺陷和造成GORBA性能低下的原因。从GORBA产品和GORBA应用开发者的角度出发，指出了一些提高GORBA性能的方法。首先对GORBA技术进行简单介绍，接着讨论GORBA的性能要求。最后，详细介绍影响GORBA性能的几个重要因素。所提出的性能优化方法对实际系统的开发具有一定的指导意义。     

基于TR的主动专家数据库系统设计

基于TR,针对时间数据的特点,给出时序主动专家数据库系统的设计方法,并对系统的功能、结构进行了详细的描述。     

The Synchronous Approach to Designing Reactive Systems

Synchronous programming is available through several formally defined languages having very different characteristics: Esterel is imperative, while Lustre and Signal are declarative in style; Statecharts and Argos are graphical languages that allow one to program by constructing hierarchical automata. Our motivation for taking the synchronous design paradigm further, integrating imperative, declarative (or dataflow), and graphical programming styles, is that real systems typically have components that match each of these profiles. This paper motivates our interest in the mixed language programming of embedded software around a number of examples, and sketches the semantical foundation of the Synchronie toolset which ensures a coherent computational model. This toolset supports a design trajectory that incorporates rapid prototyping and systematic testing for early design validation, an object oriented development methodology for long term software management, and formal verification at the level of automatically generated object code.     

Human Factors Experiments in Designing Interactive Systems

Successful industrial design gracefully unites esthetics and function at minimum cost. However, designers face special problems when they apply their skills to interactive computer systems.     

实时协同设计系统的设计与实现

分析了基于对象的协同设计系统中操作冲突的特点，给出了冲突与相容关系及其基于逻辑时间钟的冲突检测方法和一致性保证算法。在此基础上，讨论了一个实时协同设计系统的设计方面有关的关键技术，并用一个实例验证了系统的效能。     

Pervasive Java

Highlights pervasive Java - a surge of wireless and mobile platform standardization activities led by Sun Microsystems. Driven by a fast-pace proliferation of portable devices and appliances with embedded computers, pervasive Java (also called wireless Java and mobile Java) attempts to bridge the gap between disparate devices and platforms, and profitable business and application development.