Accountable Web-computing

Web-based computing (WBC) is a modality of collaborative computing wherein "volunteers" register at a Web site, receiving one (usually compute-intensive) task to compute at each visit and returning the results from that task at the subsequent visit. The security of a WBC project is enhanced if the owner of the Web site can easily keep track of which "volunteer" computed which tasks, thereby endowing the project with accountability. We develop a framework for constructing computationally lightweight schemes for endowing WBC projects with accountability. The framework is built around the notion of a directly computed task allocation function (TAF) that reserves a dedicated subset of the Web site's tasks for each "volunteer." We show how TAFs simplify the data structures needed to link "volunteers" with their tasks, even when "volunteers" are allowed to join and leave the WBC project dynamically. We then design a methodology for constructing easily computed TAFs that enhance the efficiency of the accountability scheme.     

Agent技术在Web服务中的应用探讨

Web服务是一组采用面向服务的体系架构的基于标准的Web协议的软件构件,而Agent是一种在某个环境中自主行动以实现其设计目标的智能化软件实体.Web服务与多Agent系统(MAS,Multi-Agent System)在架构、范例和技术方法等方面具有很大的相似性.Web服务的可信性是未来计算机软件发展关键的问题,实现Web服务在分布式环境下的协同式测试具有一定的挑战性.本文在探讨Web服务与Agent技术的共性的基础上,分析并总结了Agent技术在Web服务中的应用.针对Web服务测试的开放性、协同性、动态性和不确定性等特点,结合Agent系统的自主性、反应性、适应性和社会性,本文提出了一种基于MAS的Web服务测试框架(MAST,Multi-Agent-based Service Testing),并对其关键技术进行了探讨.     

Social intelligence design for the Web

Web intelligence reflects the view that eventually we will build a totally new kind of collective intelligence on the Web computing infrastructure. To reach this goal we must solve several major problems. For example, embedding Web computing into our everyday lives and society poses a more difficult problem than engineers might think. Because new technologies often consume financial resources without providing a comparable benefit, we must pay close attention to the social aspects of intelligence and how Web computing can augment knowledge processes, an attitude that underlies social intelligence design. Computer-supported collaborative work takes a similar approach, focusing on well-structured, goal-oriented groups Social intelligence design, on the other hand, highlights collective knowledge processes in informal, loosely coupled groups. It thus focuses not only on technological development for Web intelligence but also on the design and analysis of a social framework for embedding Web intelligence into everyday life.     

面向Web Services的模型驱动开发方法

随着分布式对象技术的发展和电子商务应用的扩大，Web Services技术应运而生。由于在解决异构软件的交互和企业系统集成问题上表现了极大潜力，因此学术界和工业界对Web Services都备加关注。MDA是OMG提出的用于解决不同中间件系统交互和集成问题的新的软件开发方法，是目前软件工程领域最引人注目的研究热点。本文阐述了Web Services和MDA的基本概念，对二者的交叉研究进行了分析和综述，提出了面向Web Services的模型驱动开发框架，并对未来工作做了展望。     

Grids and Grid technologies for wide‐area distributed computing

The last decade has seen a substantial increase in commodity computer and network performance, mainly as a result of faster hardware and more sophisticated software. Nevertheless, there are still problems, in the fields of science, engineering, and business, which cannot be effectively dealt with using the current generation of supercomputers. In fact, due to their size and complexity, these problems are often very numerically and/or data intensive and consequently require a variety ofheterogeneous resources that are not available on a single machine. A number of teams have conducted experimental studies on the cooperative use of geographically distributed resources unified to act as a single powerful computer. This new approach is known by several names, such as metacomputing, scalable computing, global computing, Internet computing, and more recently peer‐to‐peer or Grid computing. The early efforts in Grid computing started as a project to link supercomputing sites, but have now grown far beyond their original intent. In fact, many applications can benefit from the Grid infrastructure, including collaborative engineering, data exploration, high‐throughput computing, and of course distributed supercomputing. Moreover, due to the rapid growth of the Internet and Web, there has been a rising interest in Web‐based distributed computing, and many projects have been started and aim to exploit the Web as an infrastructure for running coarse‐grained distributed and parallel applications. In this context, the Web has the capability to be a platform for parallel and collaborative work as well as a key technology to create a pervasive and ubiquitous Grid‐based infrastructure. This paper aims to present the state‐of‐the‐art of Grid computing and attempts to survey the major international efforts in developing this emerging technology. Copyright © 2002 John Wiley & Sons, Ltd.     

On Composite Web Services Provisioning in an Environment of Fixed and Mobile Computing Resources

We present a framework for Web services provisioning in a hybrid environment of fixed and mobile computing resources. Several obstacles still hinder the seamless provisioning of Web services in mobile environments. Examples of such obstacles are: throughput and connectivity of wireless networks, limited computing resources of mobile devices, and risks of communication channel disconnections. In the proposed framework, software agents represent users, providers of services, and providers of resources. The business logic of composite services is expressed as a process model using statecharts formalism. Among other things, the use of agents provides an infrastructure that has the ability to handle disconnections during service preparation for execution. The framework also integrates a service execution planning approach to optimally select computing resources (fixed or mobile) on top of which services will be executed.     

采用构件组装技术协同开发Web应用的方法

在云计算环境下,引入网络化的协同开发机制,能优化Web应用的开发过程,缩短开发周期,提高Web应用的开发效率。提出了一种采用构件组装技术协同开发Web应用的方法。在该方法中,Web应用的功能或流程活动将以构件为单位进行划分。划分出的构件可以进一步地拆分成多个子构件,并分别以开发任务的形式发出。开发者可以接受任务,并在构件开发模板和自动生成的代码框架下进行开发。开发出的构件会被统一回收,并组装成对应于原功能或者原业务流程活动的构件。为了验证方法的可行性和有效性,实现了一个基于协同开发Web应用的构件组装工具,以及用于自动生成代码框架的离线开发工具。     

Clayworks: Toward user-oriented software for collaborative modeling and simulation

We consider the development of software systems that integrate collaborative real-time modeling and distributed computing. Our main goal is user-orientation: we need a collaborative workspace for geographically dispersed users with a seamless access of every user to high-performance servers. This paper presents a particular prototype, Clayworks, that allows modeling of virtual clay objects and running computation-intensive deformation simulations for objects crashing into each other. In order to integrate heterogeneous computational resources, we adopt modern Grid middleware and provide the users with an intuitive graphical interface. Simulations are parallelized using a higher-order component (HOC) which abstracts over the web service resource framework (WSRF) used to interconnect our worksuite to the computation server. Clayworks is a representative of a large class of demanding systems which combine collaborative, user-oriented modeling with performance-critical computations, e.g., crash-tests or simulations of biological population evolution.     

Development of an integrated-collaborative decision making framework for product top-down design process

A process model based on product function and physical topology structure is proposed. This model decomposes the product top-down design process into module design task, part design task, design parameter and dependencies among them. According to the characteristics of the design process, an integrated collaborative design software framework is designed, which includes module task agent, part task agent and sensitivity-based collaborative design method for agents. The system is developed with Java and Web technologies and applied to the transmission design case to demonstrate its utilization and efficiency.     

Cloud Computing: Does Nirvana Hide behind the Nebula?

At the core of cloud computing is a simple concept: software as a service, or SaaS. Whether the underlying software is an application, application component, platform, framework, environment, or some other soft infrastructure for composing applications to be delivered as a service on the Web, it's all software in the end. But the simplicity ends there. Just a step away from that core, a complex concoction of paradigms, concepts, and technologies envelop cloud computing.     

一种基于本体的语义Web服务发现模型

Web服务已经成为互联网中最为重要的一种计算资源和软件资产,Web服务的大量涌现对服务发现提出了挑战。Web服务发现的关键是Web服务的语义描述的准确性和Web服务检索引擎的检索效率。提出了一种基于本体的Web服务描述方法,采用OWL-S对Web服务进行语义描述,并提出了针对性的Web服务检索引擎。通过试验,该模型结合语义Web服务技术实现Web服务的动态查找与组合,可提高Web服务发现的查全率和查准率。     

An agent-based service-oriented integration architecture for collaborative intelligent manufacturing

The rapidly changing needs and opportunities of today's global market require unprecedented levels of interoperability to integrate diverse information systems to share knowledge and collaborate among organizations. The combination of Web services and software agents provides a promising computing paradigm for efficient service selection and integration of inter-organizational business processes. This paper proposes an agent-based service-oriented integration architecture to leverage manufacturing scheduling services on a network of virtual enterprises. A unique property of this approach is that the scheduling process of an order is orchestrated on the Internet through the negotiation among agent-based Web services. A software prototype system has been implemented for inter-enterprise manufacturing resource sharing. It demonstrates how the proposed service-oriented integration architecture can be used to establish a collaborative environment that provides dynamic resource scheduling services.     

A Collaborative Framework for Mould Design Based on Service-Oriented Architecture

Aiming at improving the traditional object-oriented three-layer architecture for collaborative design, a service-oriented framework for mould design is established by adding a Web service layer to decoupling the direct linking of user interface to functional modules,making the system being platform independent and programming language independent,greatly facilitating the reuse of existing software and hardware resources. .NET technology is adopted to implement the framework. An example scenario is introduce...     

面向普适环境的协同设计框架研究

提出了一种面向普适环境的协同设计框架。该协同设计框架在现有分布协同对象计算技术和网格服务的基础上,引入了普适环境“随时随地”和“透明”的思想,巧妙地把协同设计技术融入第三代计算环境中。该文讨论了普适计算的相关理论,也涉及了网格计算的相关技术。并且建立了第三代计算环境下分布式协同设计模型。该框架能够很好地利用各种网络资源,随时随地的进行产品设计开发。最后简要介绍该框架在在自主开发的HUST-CAIDS中的初步应用。     

CoLab: A New Paradigm and Tool for Collaboratively Browsing the Web

Widespread adoption of Web technologies, particularly in professional and educational areas, has motivated new research efforts with the objective of designing new interaction mechanisms based on Web technologies. Within this framework, collaborative Web browsing (cobrowsing) aims at extending currently available Web browsing capabilities in order to allow several users to "browse together" on the Web. Such a browsing paradigm can have many useful applications, for instance, in e-learning, for collaboratively searching and retrieving documents, and for online assistance (helpdesk). A cobrowsing system should provide all the facilities required for allowing users to establish and release, in a very simple and flexible way, browsing synchronization relations as well as interactions with continuous media presentations embedded within Web pages. This paper presents the design, modeling, and implementation of the cobrowsing system called CoLab. CoLab provides all the functionalities required for allowing users to collaboratively browse the Web, and a first experimental version of the tool has been implemented and is fully operational     

Structural model of team-based learning using Web 2.0 collaborative software

This study examines the phenomena occurring among team members during their participation in team-based learning using Web 2.0 collaborative software. Based on the Grounded Theory approach, this study analyzes students' feedback related to team collaborative learning using Web 2.0 collaborative tool. Data analysis yields a structural model of team-based learning facilitated by Web 2.0 collaborative software. This study draws inferences to suggest that Web 2.0 collaborative learning environment uncovers diverse communication media in support of synchronicity and group awareness. Subsequently, synchronicity and group awareness promote team-based learning. This study also reveals that four factors, namely, synchronicity, group awareness, learner autonomy and collective intelligence, support team-based learning facilitated by Web 2.0 technology.     

基于UDDI的Web服务平台研究

分析了软件复用及软件开发的现状,结合当前流行的Web服务技术提出了一种基于Web服务的软件开发新模式。基于UDDI的Web服务平台则是实现这种软件开发模式的基础,该服务平台充当不同软件开发者之间的中介,为这种协作式软件开发模式提供合作服务,并充分体现了软件就是服务的思想。     

一种面向任务关键系统的RISC风格的协作构架

The collaborative framework for the mission and safety critical system is required to support multiple quality of service properties. A RISC style collaborative framework is provided to meet this requirement. The collaborative characters of mission and safety critical system are discussed and the reliable multicast that supports collaborative computing is discussed emphsis on.     

A model-driven workflow fragmentation framework for collaborative workflow architectures and systems

This paper focuses on a workflow distribution methodology for rationally deploying workflow models onto a distributed workflow system running on cloud computing environments, and we particularly lay a stress upon that those workflow systems operable on cloud computing environments are dubbed collaborative workflow systems, which are not only built upon the collaborative workflow architectures proposed in the paper, but pursuing the so-called collaborative computing paradigm characterized by focusing collaboration over cloud computing environments. The essential idea of the workflow distribution methodology is about how to fragment a workflow model and how to allocate its fragments to each of the architectural components configuring the underlying collaborative workflow architecture and system. As a reasonable solution to realize the essential idea, the paper proposes a model-driven workflow fragmentation framework, which provides a series of fragmentation algorithms that semantically fragmentate a workflow model by considering the semantic factors - performer, role, control-flow, data-flow, etc. - of the ICN-based workflow model as fragmentation criteria. The algorithms are classified into the vertical fragmentation approach, the horizontal fragmentation approach, and the hybrid approach of both. Conclusively, this paper conceives a possible set of collaborative workflow architectures embedding the collaborative computing paradigm, and describes the detailed formalism of the framework and about how the framework works on those collaborative workflow architectures and systems.     

基于SNS的Web协作学习系统设计

随着Web2.0的快速发展,具有社会特征的SNS软件不断涌现,基于SNS平台的Web协作学习逐渐成为一种新型学习模式。提出了一种基于SNS的Web协作学习模式,并结合国内主流的SNS平台进行二次开发,设计了一个面向SNS的Web协作学习系统,主要实现了个人社区、协作学习社区、文件共享和问答系统等模块。实践证明该系统能够实现高效的Web协作和资源共享,能够帮助学习者更好地交流学习心得和分享学习成果,从而增强学习者的学习兴趣和解决问题的能力。