如何构建运营级视讯网络

20世纪90年代，多媒体通信得到了蓬勃发展，会议电视作为多媒体通信的代表，伴随着通信网络、计算机等技术的发展演变，呈现出强劲发展态势。     

多媒体在计算机网络中的发展和应用

多媒体在计算机网络中的发展和应用是计算机和通信领域发展的一个新方向。本文首先介绍了计算机网络和媒体技术的发展，然后阐述了多媒体通信的关键技术及多媒体通信一可视电话和高速局域网对多媒体的支持；最后计论了多媒体网络的发展趋势。     

多媒体通信技术及其在信息高速公路中的应用

多媒体通信技术及其在信息高速公路中的应用电子科技大学光纤通信国家重点实验室郭志永国营成都中亚无线电厂杨大华随着通信事业的蓬勃发展，多媒体通信技术日益受到各国的重视。多媒体通信是多媒体计算机与多媒体通信网的有机结合。依靠功能强大的计算机（包括ＰＣ机与工...     

C代码在THS320C54X上的手工汇编优化

随着DSP技术的不断发展和完善．数字信号处理的应用范围越来越广泛。工控、计算机、通信和消费电子产品中，都会找到它的影子。近年来，随着多媒体通信的蓬勃发展，DSP也越来越多的应用在多媒体通信。在多媒体通信中，DSP多用于语音压缩和图像处理等方面，而这些都需要巨大的计算量。在实时通信中．     

多媒体通信综述

近年来,随着多媒体技术蓬勃发展,各类通信网络上出现了越来越多的多媒体应用。多媒体技术与有线和无线通信(电话、电报、传真、数据)网络、广播和闭路电视网络、微波和卫生通信网络、计算机远程和地区性局域网络等各种通信技术相结合,产生了一种边缘性技术——多媒体通信。多媒体通信是一项综合性技术,涉及多媒体、计算机及通信等领域,它集计算机的交互性、网络的分布性和多媒体信息的综合性于一体,为人类提供了全新的服务。多媒体通信是继电报、电话、传真之后的第四代通信手段。     

计算机协同工作技术

本文介绍了在人类社会信息化发展的大背景下，由通信技术与计算机及其网络技术相融合而发展起来的计算机协同工作（ＣＳＣＷ，ＣｏｍｐｕｔｅｒＳｕｐｐｏｒｔｅｄＣｏｏｐｅｒａｔｉｖｅＷｏｒｋ）技术的发展背景、基本概念及广泛的应用领域，并分析了计算机协同工作系统的关键技术；指出计算机协同工作技术是计算机网络技术发展的重要方向，必将带来人们协作方式的发展和协作效率的提高，并推动人类社会信息化进程。     

交换式快速以太中点—点多媒体通信的研究

多媒体通信对计算机网络技术提出了更高的要求，交换式快速以太网是目前流行的高速局域网技术之一，本文通过在交换式快速以太网中进行地一点－点通信测试实验，分析了在交换式快速以太网中进行点－点多媒体通信的若干问题。     

我国多媒体通信技术的发展与应用

多媒体通信技术是多媒体计算机技术、电视技术和通信技术相结合的产物,同时融入了多媒体的复合性、计算机的交互性、电视的实时性以及通信的分布性.如今,随着信息时代的飞速发展和高新技术的不断涌现,多媒体通信已成为一种基本的通信方式.     

交换式快速以太网中点—点多媒体通信的研究

多媒体通信对计算机网络技术提出了更高的要求，交换式快速以大网是目前流行的高速局域网技术之一，本文通过在交换式快速以太同中进行的点—点通信测试实验，分析了在交换式快速以大网中进行点—点多媒体通信的若干问题．     

分布式多媒体网络协作平台的研究

计算机支持的协同工作(CSCW)体现并符合信息时代人们工作的分布性、交互性和协同性的特征,涉及分布式系统、计算机通信、人机交互、人工智能和社会科学等诸多方面,因而日益受到人们的重视。文章结合CSCW技术提出了一个通用分布式多媒体网络协作平台的体系结构,分析了多媒体通信,用户协作信息管理,协同应用的并发控制机制等问题,最终实现了分布式、网络传输、多媒体技术在平台中的集成,并介绍了几个应用实例。     

Demographics and Behavior of the Chilean Internet Population

When a computer network connects people or organizations, it is a social network. Yet the study of such computer-supported social networks has not received as much attention as studies of human-computer interaction, online person-to-person interaction, and computer-supported communication within small groups. We argue the usefulness of a social network approach for the study of computer-mediated communication. We review some basic concepts of social network analysis, describe how to collect and analyze social network data, and demonstrate where social network data can be, and have been, used to study computer-mediated communication. Throughout, we show the utility of the social network approach for studying computer-mediated communication, be it in computer-supported cooperative work, in virtual community, or in more diffuse interactions over less bounded systems such as the Internet.     

一种用于协作通信系统的频率同步算法

在协作通信领域中频率同步已成为研究的焦点之一。由于其系统特性,载波频率偏移（Carrier Frequency Offset,CFO）普遍存在。考虑了协作通信系统中的多频偏估计问题,提出了一种新的用于协作通信系统的频率同步算法ECR,通过中继节点在转发前进行频率再补偿,使得中继节点转发的信号的发送频率均与源节点的发送频率保持一致,继而目的节点的频率同步问题得以简化,同时系统不会随着中继节点的增多而变得复杂。仿真结果表明,所提出的同步方法在协作通信系统中可以取得较好的系统性能。     

Intelligent support for activity management (ISAM): an architectureto support distributed supervisory control

Distributed supervisory control is the monitoring and control of complex, dynamic, highly automated systems by a team of human operators. As such, it is an example of a cooperative work environment. The goal of this paper is to analyze the nature of cooperative work in distributed supervisory control environments and describe implications for computer support. In particular, we argue that flexible support for activity management is a key requirement for computer support for distributed supervisory control, and we propose the intelligent support for activity management (ISAM) architecture as one infrastructure for doing so. The design and implementation of ISAM draws from previous work on intelligent operator's associate systems and computer-supported cooperative work (CSCW) systems. A graphical user interface to ISAM and an evaluation study of this system in the context of team supervisory control are also described     

A Prototype of a Cooperative Visualization Workplace for the Aerodynamicist

Several feasibility studies for cooperative visualization were performed based on an existing modular visualization system. Two different architectures for the implementation of a cooperative system were identified, implemented and tested. One architectural model, the broadcast model, assumes either one single visualization system running on a central facility driving multiple displays or in case of cooperative work it assumes that each visualization module drives multiple displays. The second model, the synchronized visualization systems, features distributed visualization tools with synchronization mechanisms. The synchronization ensures that all partners create identical images from identical data. This model requires special control features to avoid conflicts created by user-interaction. Both architectures are complete by adding bi-directional video connection and audio communication over the network plus offering remote cursor functionality. Two prototype implementations were produced to compare the two architectures and to evaluate the feasibility of cooperative visualization on existing hardware. Because of the poor access to wide-area networks, the prototypes were tested in a local area network. Visualization protocols, data communication, video and audio ran on a standard Ethernet based on TCP/IP communications. The tests were done using typical data from aerodynamics or numerical flow simulations. In spite of the limits due to low network bandwidth and slow performance of some hardware components the second architecture using the synchronized systems seems to be useful and feasible even under today's circumstances. There are no additional features identified which would be needed to run the cooperative visualization on a wide area network but a higher network throughput would be required.     

协同编辑中维护操作意愿的文档标注方法*

在实时协同编辑系统中,操作意愿一致性维护是国际上提出的新概念,是协同系统一致性维护的重要方面.文档标注文法通过对共享文档进行恰当标注,屏蔽并发操作对共享文档造成的影响,使得操作在任意协作点上执行时的环境与操作产生的环境一致,从而有效地维护操作意愿一致性.结合实际应用中的具体操作,重点论述文档标注方法以及相应的控制算法.     

Hohfeld in cyberspace and other applications of normative reasoning in agent technology

Two areas of importance for agents and multiagent systems are investigated: design of agent programming languages, and design of agent communication languages. The paper contributes in the above mentioned areas by demonstrating improved or novel applications for deontic logic and normative reasoning. Examples are taken from computer-supported cooperative work, and electronic commerce.     

基于LQR的耦合动态互联系统分布式协作 负载均衡优化控制

针对一类非等同非线性耦合互联系统,提出分布式协作负载均衡优化控制方法.将子系统间的通信联系建模成有向图,借助输入输出反馈线性化技术,将耦合互联系统的分布式负载均衡控制设计问题转化为广义线性多智能体系统的同步跟踪问题;基于最近邻原则和LQR方法,设计增益可调的分布式协作负载均衡优化控制律,耦合强度依赖于通信拓扑,控制增益依赖于子系统模型;借助矩阵变换方法,整个闭环系统的渐近稳定性可以解耦成每个子系统的稳定性,在假定通信拓扑只含有生成树的条件下,借助李亚谱诺夫函数,可证明整个闭环系统是稳定的,且通过调节控制增益,可以得到期望的响应速度.仿真结果验证了所提出控制方法的有效性及可行性.     

一种CSCW环境下群组自动机树同步模型

给出一种在协同环境下的基于群组自动机的动态树同步模型,模型对操作同步和状态同步都给出了能够具体到实际过程每一步的描述。在考察状态同步时,把它限制在引起更新冲突的系统最小局部进行,效率得到了保证;由于模型在描述系统时采用递归性质的算法,极适合于描述动态系统。     

Technology for care networks of elders

Computer-supported coordinated care uses technology to aid the network of people who support an elder living at home. CSCC supports improved communication among individuals and a balanced distribution of responsibilities to allow the elder to live at home despite increasing care needs. The problem of coordinating the care of elders living at home hasn't been well defined or explored. We focus on using technology to aid the elder's entire support network. To distinguish this space from the broader research issues of computer-supported cooperative work, we call it computer-supported coordinated care and propose that it is a meaningful focus for the pervasive computing, CSCW, and human-computer interaction (HCI) communities.     

Opportunities and challenges in improving surgical work flow

Safe and efficient surgical operations depend on a work environment larger than the individual operating room (OR) and on communications at different levels of the hospital organization. Extensive communication is needed before and during surgery to ensure that surgical rooms, equipment, and supplies; patients; surgeons; supporting personnel; and accompanying documentation are all ready at the appropriate times. In this article, we compile the results of three of our studies of communication activities outside ORs, with the goal of identifying opportunities and challenges in the workflow of surgery. The first study demonstrates the amount of communication work performed by OR coordinators. The second study demonstrates the potential functions of a whiteboard in communication. The third study describes an organizational learning strategy of proactive event reporting. We apply computer-supported cooperative work and organizational learning concepts to the findings and suggest ways in which information technology may improve surgical workflow.