异构CAD系统协同框架与互操作

协同CAD通过网络支持不同地域的设计人员实时地完成产品设计或决策任务,以提高群体协同工作效率;异构CAD系统协同将分布的不同的CAD系统,如ProE、UG、SolidWork等业界比较成熟且是主流的商业CAD系统,集成在一个框架平台下,从而支持人们更方便地协同工作;文章讨论了异构CAD系统协同的体系结构与共享感知问题,提出了一个支持共享感知的复制式系统结构模型;进一步将现有商业CAD系统引入到该模型中,给出了一个基于构件的协同CAD中间件框架模型,讨论了中间件接口和CAD系统的互操作。     

Software Framework for Managing Heterogeneity in Mobile Collaborative Systems

Heterogeneity in mobile computing devices and application scenarios complicates the development of collaborative software systems. Heterogeneity includes disparate computing and communication capabilities, differences in users needs and interests, and semantic conflicts across different domains and representations. In this paper, we describe a software framework that supports mobile collaboration by managing several aspects of heterogeneity. Adopting graph as a common data structure for the application state representation enables us to develop a generic solution for handling the heterogeneities. The effect external forces, such as resource constraints and diverging user interests, can be quantified and controlled as relational and attribute heterogeneity of state graphs. When mapping the distributed replicas of the application state, the external forces inflict a loss of graph information, resulting in many-to-one correspondences of graph elements. A key requirement for meaningful collaboration is maintaining a consistent shared state across the collaborating sites. Our framework makes the best of maximizing the state consistency, while accommodating the external force constraints, primarily the efficient use of scarce system resources. Furthermore, we describe the mobility aspects of our framework, mainly its extension to peer-to-peer scenarios and situations of intermittent connectivity. We describe an implementation of our framework applied to the interoperation of shared graphics editors across multiple platforms, where users are able to share 2D and 3D virtual environments represented as XML documents. We also present performance results, namely resource efficiency and latency, which demonstrate its feasibility for mobile scenarios.     

一种基于规范的可信协同系统分析设计框架

针对可信协同系统分析建模与设计问题,提出了RBN-T模型,分析了模型中的可信保障机制及策略.提出了基于RBN-T模型的可信协同系统分析建模过程,以具体的实例说明了RBN-T模型在可信协同系统分析建模与设计上的可用性.RBN-T模型把基于角色的规范管理提升到适合可信协同系统分析建模与设计的层次,从而有利于在协同系统开发的早期阶段就关注可信问题.     

协同开发模式在磁场检测仪开发中的应用

针对磁场检测仪需要众多软硬件开发人员协同开发的问题,引入Redmine项目管理平台进行项目开发的协同管理。采用Proteus实现下位机硬件和嵌入式软件的并行开发,引入嵌入式系统和SVN版本管理器对嵌入式软件各模块进行协同开发。采用Bus Hound实现上位机和下位机软件的并行开发。最终,该协同开发模式的引入使得本项目开发用时比原计划用时减少25%,同时项目质量也有提高。     

An Exploratory Study: Supporting Collaborative Multimedia Systems Design

Multimedia systems design generally requires a collaborative effort from a group of designers with a variety of backgrounds and tasks, such as content experts, instructional designers, media specialists, users, and so forth. However, currently available design tools on the market are mainly designed for a single user. Tools intended to support a collaborative design process should coordinate independent activities of individual designers.This research investigated support for work groups engaged in designing multimedia systems. Specifically, it discussed a new collaborative design environment, called the KMS (Knowledge Management System)-based design environment, in which multimedia designers could share their design knowledge freely. Through two experimental groups, the research investigated impacts of the KMS-based design environment on their collaborative design activities (knowledge creating, knowledge securing, knowledge distributing, and knowledge retrieving activities). The research findings showed that the KMS-based design environment was a promising environment for collaborative multimedia systems design. More specifically, the research findings indicated that the KMS-based design environment supported creating, securing, and retrieving knowledge, but it did not support distributing knowledge. In addition, the research found that the social interactions between group members played important roles in the success of the collaborative multimedia systems design and that the KMS-based design environment did not support the socialization of group members. Furthermore, the research found that the inability of the KMS-based design environment to support the socialization was linked to its low performance level in supporting the knowledge distributing activity. The research explored the desired features of a collaborative support tool for multimedia systems design.     

Collaborative Writing Is Hard to Support: A Field Study of Collaborative Writing

This paper documents the results of a field test of Instant Update, a collaborative writing tool by a geographically dispersed department at the MITRE Corporation. Thirty-six participants were given Instant Update software and free training and support in exchange for their cooperation with data collection. These participants spent a great deal of time writing and communicating with each other about their written work. They began the pilot test with enthusiasm, using Instant Update for many types of documents and anticipating many benefits. After three months of experience they rated the actual benefits they received from the software lower than they had expected. Their usage became much more refined. They continued to use it for some types of documents, but stopped for others. The collaborative writing software was used successfully to create joint documents that have a consistent format and are produced on a regular basis (such as weekly activity reports) and for documents that provide access to shared information (such as a vacation calendar). It was used less successfully for the production of documents that require a complex work flow and have a changing group of contributors. We concluded that although collaborative writing is difficult to support and the currently available collaborative writing tools need to be improved before they can meet the needs of most co-writers, they are adequate for some types of tasks. Documents that are well defined and are created by experienced users who can cooperate well can benefit from the currently available tools.     

一种基于SOA架构和网格计算的协同商务平台框架研究

首先提出了网络环境下协同商务的模型,采用面向服务体系(SOA)的思想,基于网格服务构建了一种协同商务平台的框架,用网格服务封装企业内部和企业之间的业务系统接口.通过网格服务的发现、集成、调用实现协同电子商务.其目的是实现企业内部、供应链企业之间以及企业外部各层次(客户、政府和其他机构)之间的协同.最后给出了这种框架的实...     

协同推荐系统检测模型的一种优化方法

研究表明协同推荐技术容易受到攻击。由于现有的检测模型对低填充规模攻击的检测效果不理想,本文结合检测模型特点,改进Pearson相似度计算方法。其思想是,降低共同评分项目对用户相似度程度的影响,从而降低填充规模较小的攻击数据与真实用户之间的相似度。实验结果表明该方法对低填充规模攻击有较好的抗攻击性。     

A Framework for Collaborative, Content-Based and Demographic Filtering

We discuss learning a profile of user interests for recommending information sources such as Web pages or news articles. We describe the types of information available to determine whether to recommend a particular page to a particular user. This information includes the content of the page, the ratings of the user on other pages and the contents of these pages, the ratings given to that page by other users and the ratings of these other users on other pages and demographic information about users. We describe how each type of information may be used individually and then discuss an approach to combining recommendations from multiple sources. We illustrate each approach and the combined approach in the context of recommending restaurants.     

Autonomy and Common Ground in Human-Robot Interaction: A Field Study

The use of robots, especially autonomous mobile robots, to support work is expected to increase over the next few decades. However, little empirical research examines how users form mental models of robots, how they collaborate with them, and what factors contribute to the success or failure of human-robot collaboration. A two-year observational study of a collaborative human-robot system suggests that the factors disrupting the creation of common ground for interactive communication change at different levels of robot autonomy. Our observations of users collaborating with the remote robot showed differences in how the users reached common ground with the robot in terms of an accurate, shared understanding of the robot's context, planning, and actions - a process called grounding. We focus on how the types and levels of robot autonomy affect grounding. We also examine the challenges a highly autonomous system presents to people's ability to maintain a shared mental model of the robot     

基于对等模型的分布式协同设计系统

为了解决分布式协同设计系统中的信息快速检索以及多副本同步等问题,引入了对等模型,给出了该系统的功能模型、信息检索模型等。提出了DHT的对等信息检索方法,保证了用户能够在分布式协同设计系统中快速共享资源。采用基于DHT的分布式互斥等算法作为协同数据的一致性维护方法,给出了系统的具体实现方法和实例。     

Collaborative Online Examinations: Impacts on Interaction, Learning, and Student Satisfaction

This paper presents the results of a field experiment on online examinations facilitated by collaboration support systems. In particular, it examines collaborative learning and virtual teams through online examinations as an assessment procedure, compared to traditional examinations. Assessment is increasingly regarded as an important part of the learning process. Applying constructivism and collaborative-learning theories, the collaborative examination process features students' active participation in various phases of the exam process through small group activities online. A 1 times 3 field experiment evaluated the collaborative online exam compared with the traditional in-class exam, and the participatory exam, where students participated in the online exam processes without groups. Data analysis using results from 485 students indicates that collaborative examinations significantly enhance interactions and the sense of an online learning community and result in significantly higher levels of perceived learning     

网络入侵检测系统和防火墙集成的框架模型

本文首先分析了防火墙和网络入侵检测系统在网络安全体系中丰在的不足,介绍了在CIDF的框架下建立的一个集成防火墙和入侵检测系统的模型,详细分析了这种集成给网络带来的安全性提高,最后指出了未来工作的方向。     

基于综合集成法的复杂产品协同设计过程模型及框架研究

建立过程模型及框架,将设计过程有效地表达出来,是协同设计的基础。 论文针对复杂产品设计过程的特征,根据综合集成法,建立了一个以时间、粒度、并行度三 维分布的多层次复杂产品协同设计过程模型。该过程模型在时间维强调多阶段综合,在并行 度维强调多专业综合,在粒度维强调分解与综合的迭代。在该过程模型基础上,结合专家体 系、知识体系、机器体系,提出基于综合集成法的复杂产品协同设计过程框架。该框架中, 机器体系依靠知识体系中的知识,给专家群体提供帮助,专家群体在机器体系提供的项目管 理、群体研讨、协同决策、三维可视化等支持工具帮助下,实现人机结合、多专业结合、多 阶段结合的协同设计过程,以提高复杂产品的协同设计效率。最后介绍了相关原型系统。     

分布式协作模型及应用研究

With the development of the Web technology,the application environment has acquired many new characters such as dynamic, openness,distribution and information uncertainty.The processing mode of application systems is more complicated than ever.For example,it requires application systems to have more community processing ability,interactive ability,distributed processing ability and collaborative ability.Accordingly the research and development of the computer application system transited from client/server information processing system into distributed collaborative processing system based on Web.Especially in the environment where the information and resources are highly distributed,the accomplishment of complicated tasks is dependent more on the resources coordination,information sharing and coordinator collaboration.The collaboration is one aspect of the group behavior and its goal is to provide a optimal method to utilize the resource through the information interaction and to solve the task which couldn't be accomplished by each coordinator alone and get the more total benefits than the sum of each benefit.The collaboration problem is the important one for distributed tasks processing.This paper surveys,the research and application status of distributed collaborative models and several representative architectures of distributed collaborative processing are proposed.However,the existing problems and the future researching direction are presented.     

协同CAD系统中操作语义共享技术研究

研究了协同CAD系统的操作语义,给出了操作语义的定义和描述方法、操作语义的识别技术以及基于本体的映射模型,在此基础上提出了一种基于操作语义共享的CAD协同框架,最后给出了基于该框架的一个原型系统。     

异构系统中的Web服务器软件框架研究

在服务器端加入GPU或MIC等协处理器可以提升性能。但是,传统Web服务器端软件不能充分发挥多核CPU+MIC协处理器异构硬件体系的性能。为解决该问题,针对该硬件体系提出了一种新的Web服务器软件框架。该软件框架基于分阶段事件驱动模型,将部分动态请求调度至MIC协处理器执行,并可在多核CPU和MIC协处理器上并行处理动态请求。同时,通过采用自适应调度算法兼顾了CPU和MIC协处理器间的负载均衡。仿真实验表明,该模型在平均响应时间、吞吐量等方面均优于传统的基于先到先服务(First Come First Served,FCFS)的Web服务器软件模型。     

平行应急疏散系统:基本概念、体系框架及其应用

突发事件通常具有难以预测、多成因关联、危害性大及演变复杂等特点,应急情况下如何安全高效疏散人员是应急管控领域的重要研究内容.本文将基于人工系统（Artificial systems,A）、计算实验（Computational experiments,C）、平行执行（Parallel excution,P）方法的平行系统理论引入到应急管控领域,提出平行应急疏散系统（Parallel emergency evacuation systems,PeES）基本概念,构建系统体系框架及集成平台,并介绍人工应急疏散系统、计算实验、平行执行等主要功能模块的基本功能及实现方法.通过PeES能实现虚实应急疏散系统的管理与控制、应急方案的实验与评估以及相关人员的学习与培训.最后,以轨道交通枢纽站火灾场景下的乘客应急疏散为典型应用对平行应急疏散系统进行初步验证.     

Turing Machines, Transition Systems, and Interaction

We present Persistent Turing Machines (PTMs), a new way of interpreting Turing-machine computation, one that is both interactive and persistent. We show that the class of PTMs is isomorphic to a very general class of effective transition systems. One may therefore conclude that the extensions to the Turing-machine model embodied in PTMs are sufficient to make Turing machines expressively equivalent to transition systems. We also define the persistent stream language (PSL) of a PTM and a corresponding notion of PSL-equivalence, and consider the infinite hierarchy of successively finer equivalences for PTMs over finite interaction-stream prefixes. We show that the limit of this hierarchy is strictly coarser than PSL-equivalence, a “gap” whose presence can be attributed to the fact that the transition systems corresponding to PTM computations naturally exhibit unbounded nondeterminism.We also consider amnesic PTMs and a corresponding notion of equivalence based on amnesic stream languages (ASLs). It can be argued that amnesic stream languages are representative of the classical view of Turing-machine computation. We show that the class of ASLs is strictly contained in the class of PSLs. Furthermore, the hierarchy of PTM equivalence relations collapses for the subclass of amnesic PTMs. These results indicate that, in a stream-based setting, the extension of the Turing-machine model with persistence is a nontrivial one, and provide a formal foundation for reasoning about programming concepts such as objects with static attributes.     

Equivalence of Convolution Systems in a Behavioral Framework

In this paper the problem of system equivalence is tackled for a rather general class of linear time-invariant systems. We consider AR-systems described by linear continuous shift-invariant operators with finite memory, acting on Fréchet-signal spaces, containing the space {\cal E} ({\open R}) of infinitely differentiable functions on {\open R}. This class is in one–one correspondence with matrices of suitable sizes over the convolution algebra {\cal E} ({\open R}) of all compactly supported distributions. Using some deep results from the theory of Fréchet spaces, various necessary and sufficient conditions for system equivalence and system inclusion are formulated. It is shown that a surjectivity demand on the system defining convolution operator matrix is necessary and sufficient for being able to translate the problem of system equivalence into division properties over the convolution algebra {\cal E}({\open R}). This surjectivity condition is guaranteed if the system defining matrix over {\cal E}({\open R}) has a right-inverse over {\cal D}({\open R}), the space of all Schwartz distributions. Date received: February 9, 2000. Date revised: April 11, 2003.