基于模式转换的分布式多媒体系统的结构模型

对于分布式多媒体系统,创建合适的结构模型是其重要的研究课题之一。文章在基于模式转换的思想基础上,提出了一种分布式多媒体系统的结构模型,该模型可有效地支持多媒体对象的表现和通信。     

分布式多媒体系统中多媒体对象交换管理器的设计与实现

给出了分布式多媒体系统中多媒体对象交换管理模块的设计及实现的方法,并详细讨论了多媒体对象交换管理模块和结构模型中的其它模块之间的相互作用关系。     

煤矿多媒体安全监视监测信息管理系统的研究

文章分析了多媒体技术在矿山中的实际应用,讨论了多媒体光纤工业电视系统的组成、特点及功能,并与其它监测、监控、信息管理系统联网,形成煤矿多媒体安全监视监测信息管理系统。     

视频会议系统DMCS的设计与开发

近年来,视频会议系统特别是台式系统（又称桌面型会议系统）成为多媒体技术领域的一个研究热点。在这种背景下,进行了视频会议系统的研究,并研制了基于ＷＩＮＤＯＷＳ环境的视频会议系统原型ＤＭＣＳ（以下简称为 ＤＭＣＳ）。 ＤＭＣＳ采用了主席控制下的自由讨论会议模型,是 Ｃ／Ｓ结构的视频会议系统。最后还给出了运行测试结果。     

分布式多媒体系统资源管理的研究

分布式多媒体系统中,资源管理包括多媒体呼叫建立期间服务质量（ＱｏＳ）协商、ＱｏＳ确认过程中的资源分配,以及多媒体传输期间资源监视、ＱｏＳ重协商过程中的资源调整等内容。文章概述了资源管理研究的关键技术,包括系统层次模型、资源管理模型和任务调度算法。     

The impact of status and audio conferencing technology on business meetings

This field study examining the effects of organizational status and multimedia audio communications technology on communication patterns in business meetings confirms that high status group members verbally dominate discussions and have more control over the flow of the proceedings. However, it reveals a new and surprising finding: multimedia communications technology can in fact exaggerate status constraints in contrast to findings that there is no effect or an equalizing effect on status inequalities of text-based conferencing technology. It appears that in audio conferences, the lack of non-verbal cues that can aid turn-taking combined with (1) the participants' knowledge of the group's status hierarchy and (2) the tendency to compare oneself unfavourably to those of higher status, makes it more difficult for lower status individuals to contribute verbally to discussions than in face-to-face interactions. Such status constraints may have both positive and negative impacts on group communication effectiveness, these and implications for the design and implementation of multimedia communications technology are discussed.     

Modeling and Retrieval of Moving Objects

This paper presents a symbolic formalism for modeling and retrieving video data via the moving objects contained in the video images. The model integrates the representations of individual moving objects in a scene with the time-varying relationships between them by incorporating both the notions of object tracks and temporal sequences of PIRs (projection interval relationships). The model is supported by a set of operations which form the basis of a moving object algebra. This algebra allows one to retrieve scenes and information from scenes by specifying both spatial and temporal properties of the objects involved. It also provides operations to create new scenes from existing ones. A prototype implementation is described which allows queries to be specified either via an animation sketch or using the moving object algebra.     

Modeling Content for Semantic-Level Querying of Multimedia

Many semantic content-based models have been developed for modeling video and audio in order to enable information retrieval based on semantic content. The level of querying of the media depends upon the semantic aspects modeled. This paper proposes a semantic content-based model for semantic-level querying that makes full use of the explicit media structure, objects, spatial relationships between objects, events and actions involving objects, temporal relationships between events and actions, and integration between syntactic and semantic information.     

An Algebraic QoS-Based Resource Allocation Model for Competitive Multimedia Applications

A new class of multimedia applications require new mechanisms to consider various Quality of Services with respect to resource constraints so that they could support reliable services and utilize available resources optimally. In this paper we present a new analytical and generic resource management model that is QoS-based. The approach for resource allocation and relevant algorithms is based on a mathematically proved model that manages resource and QoS allocation intelligently so that the total system utility of is maximized. We use the constructs of application benefit functions and resource demand functions to represent the system configuration and to solve the resource allocation problems. Extensive surveys on the related work including systematic and analytical approaches are also presented.     

基于自适应节的多媒体流QoS保证的研究

分布式多媒体计算机系统的一个关键问题是保证连续多媒体流的服务质量（QoS),大多数多媒体流要求的QoS是在一定范围内,即[QoSmin,QoSmax]。为了保证QoS,计算机系统和网络系统必须分配足够的CPU、I/O、内存和网络带宽资源。在多媒体流传输过程中,这些资源的可利用率是动态变化的,尤其是带宽资源,如Internet,文中提出了自适应节的概念,采用PID调节技术,在[QoSmin,QoSmax]内,动态调节QoS,自适应动态的可利用资源变化,既保证了多媒体流的QoS,又提高了资源的利用率。