A Resource Reservation Scheme for Synchronized Distributed Multimedia Sessions

Guarantees of services in a networked environment are provided by the proper allocation and scheduling of network and system resources. A lot of research in packet scheduling, QoS routing, traffic multiplexing, etc. has been aimed at providing deterministic or statistical service guarantees, while utilizing resources efficiently. In this paper, we propose a resource reservation scheme for a class of multimedia presentations. We characterize this class of multimedia presentations as synchronized distributed multimedia sessions, which we believe are important components of many multimedia applications. In addition to multimedia presentations, the reservation scheme applies to applications with synchronized resource requirements. Based on resource inquiry and interval analysis, the scheme is also able to find feasible resource allocation schedules for resource reservation requests. Built upon a layer of resource abstraction, the scheme suits well with today's heterogeneous network environment.     

互动多媒体同步机制设计

研究了基于 MPEG-4的面向对象多媒体同步技术。在分析现有多媒体同步技术的基础上，结合 MPEG-4 系统同步机制和高级同步模型(FlexTime)，设计了层结构同步模型，以实现 MPEG-4 中各媒体对象间同步，是一种有效可行的多媒体间同步的实现方法。     

A Hypermedia Tutoring System for Design Trainers

Research and development has been undertaken on the production of hypertext-based authoring and end-user training systems, linked to a videodisc player. A hypermedia system enabled the use of animation, purpose-designed graphics, sound and fast response to enhance the learning environment. The package structure could be presented, to allow the user to move around the package, and to see at a glance the consequence of his actions. In addition, material visited by the user and decisions taken, could be stored to enable computer managed manipulation of the data structure for individual requirements.

This paper discusses one particular system for design trainers to explore various structures of training material. This videodisc-based package gives guidance on the use of multi-media authoring packages to produce material that is sensitive to the interests of each trainee at an appropriate level of understanding. The control structure required some innovative programming techniques of benefit to other researchers investigating the potential of hypermedia.     

流式媒体同步集成技术在远程教学信息系统中的应用

现代教育技术并不等于现代远程教育,在教学过程中使用了现代信息技术并不就是现代远程教育。如何将数字视频／音频信息融于Web授课课件,这是当前远程教学和教育技术领域的新课题,该文介绍远程教学信息系统建设过程中进行的探索和实践。     

COMET: A Collaborative Tutoring System for Medical Problem-Based Learning

This paper discussed about the developed collaborative intelligent tutoring system for medical PBL called Comet (collaborative medical tutor). Comet uses Bayesian networks to model the knowledge and activity of individual students as well as small groups. It applies generic tutoring algorithms to these models and generates tutorial hints that guide problem solving. An early laboratory study shows a high degree of agreement between the hints generated by Comet and those of experienced human tutors. Evaluations of Comet's clinical-reasoning model and the group reasoning path provide encouraging support for the general framework.     

基于可视语音的英语发音辅导系统

发音问题是初学英语的一大难题。在我国这样的非英语环境中,很多小学生课后缺少专业老师辅导,极易出现英语发音障碍。本文设计开发了一个基于可视语音的英语发音辅导系统EP Tutor,模拟一个卡通家教的脸部动画,生动亲切的为学生一对一辅导英语发音。本文重点讨论了系统设计理念、系统架构、部分关键功能的详细设计以及关键技术的实现。     

智能教学系统中教学策略的研究

智能教学系统(Intelligent Tutoring System,ITS)兴起于二十世纪七十年代,是一门具有深入研究与应用价值的新型教育技术.简言之,ITS就是模仿人类教学专家的经验、方法来辅助教学工作的计算机系统[1].     

一种用于系统互连的实时自主同步串行总线

针对当前小型化和高密度化的设计需求，提出了一种用于系统互连的实时自主同步串行总线，其能有效替代当前使用大量通用输入输出进行控制及指示信号传输的传统做法，实现更高效的系统板内及板间互连。     

Muse: A Multimedia Filing System

New technology is changing the way we store documents. This experimental system features flexible document retrieval, a distributed architecture, and the capacity to store many very large documents.     

Affective Tutoring System for Built Environment Management

There are quite a lot of researche performed in the world, which prove that interest, stress and learning productivity of a learner to a large extent determine study results. Moreover, learning emotionality, pleasurableness and attractiveness, which help to increase its efficiency, are stressed by various researchers. Researchers have noticed, that a student's interest, stress, learning productivity and academic achievement are quite closely related. Experts have noticed that in order to cause interest, increase learning productivity and maintain stress in a rational level of a learner it is necessary to constantly change the learning subject with regard to situational and individual interest. For this reason, an Affective Tutoring System for Built ENvironment Management (ATEN), developed by the authors of the article is very suitable. The ATEN was developed and fine-tuned in the course of the TEMPUS project “Reformation of the Curricula on Built Environment in the Eastern Neighbouring Area”. One of the ATEN innovations is that the System integrates the self-assessment and self-esteem measurement of students with multimodal biometric and intelligent methodologies and technologies. Affective Tutoring System for Built Environment Management can create a rational version of a learning process tailored to a specific student, taking into account such factors as how much the studies are interesting or difficult and the level of stress (with the help of biometric technologies). The System includes an automatic function that takes module topics and compiles an optimal set of personalised materials for a specific student. The case study submitted in this article partly demonstrates this developed System.     

A Multimedia Information Repository for Cross Cultural Dance Studies

Multimedia technologies provide effective means for studying the evolution of dance across time and space. The study may be at the micro level which analyzes the development of an individual's performance and the movements of the dancer(s) in 3D space and over the length of the dance. However, at the macro level, diffusion of dance throughout the world over a span of time may be investigated in order to trace particular dance repertoires that may have traveled across various cultures and traditions. Although clearly different with respect to the expected objectives, both micro level analysis and macro level analysis require detailed comparison of patterns on the basis of certain characteristics that are deemed significant for a given dance. These characteristics are diverse in nature and may include such parameters as design formations, use of space (including level, direction, etc.), dynamics, paraphernalia (e.g., swords, sticks, etc.), sound, and color.We present the design of a multimedia information system with two complimentary aims. The first is to automate, to the greatest degree possible, the process of comparison and analysis of dance and human movement. Much of the information about dance exists in the form of video, images, audio and written commentaries, all collected into a digital library. As dance related materials are added, a wide variety of routines are needed to extract the necessary low level features from the multimedia objects. These low level features are then interpreted to human understandable features and patterns, which will be used for analysis by specialists. The second aim is to bring artists and technologists closer in a meaningful way.     

DMTS: A Distributed Multimedia Teleworking System

Multimedia systems combine a variety of information sources, such as voice, graphics, animation, images, and full-motion video, into a wide range of applications. The paper initially categorizes existing multimedia applications into three classes: noninteractive-oriented, interactive-oriented client-server-based, and interactive-oriented peer-party-based. In particular, the paper examines interactive-oriented applications and provides an in-depth survey of the media synchronization problem for the design of these applications. The paper then presents our prototyping system, called the Distributed Multimedia Teleworking System (DMTS), which allows two or more remote systems in collaboration to access and modify multimedia data through a network in a fully synchronous fashion. The system has been developed over TCP/IP and an FDDI network, using an XVideo D/A card. The media supported by DMTS include text, graphics, voice, and video. DMTS employs a master-slave collaboration model to maintain the coherence of the text and graphics data being simultaneously modified. Moreover, DMTS also adopts effective mechanisms to reduce skew (asynchrony) and jitter delays between video and voice streams. Finally, the paper demonstrates that DMTS achieves a maximum throughput of 13 frames per second, and reveals that the throughput bottleneck resides in the hardware capture and D/A processing of video frames.     

分布式多媒体服务组合中的异常预测算法

为提高分布式多媒体服务组合系统中路径的健壮性和可靠性,提出一种基于Markov链和加权朴素贝叶斯分类器(WNBC)的异常预测算法。该算法利用Markov模型预测系统节点的资源状态信息,使用WNBC对预测的节点状态进行分类,以判断节点是否可能发生异常。实验结果表明,该算法能根据节点的状态信息预测系统节点的不同异常状态,性能较同类算法有较大的改善。     

多媒体节目时序描述的组合技术

组合性是形式描述研究的基本问题,便于大型程序的设计、分析、测试和复用.为了方便用户编制大型多媒体系统的时序描述,组合模型是必须的.目前,这样的模型有基于语言的、基于图形的、基于时间区间的和面向对象的等等.但是,这些模型描述层次过低,很难支持两个多媒体节目之间的时序描述.通过引入单位流的概念和扩展两种时序关系,研究一种多媒体节目时序描述的结构化技术,使复杂的多媒体节目易于理解,以方便用户运用组合方法把一些可以复用于不同多媒体节目的节目模块进行组合设计.     

作为多媒体系统模型的时间Petri网的同步合成

本文用一种以出现网为基网的时间Petri网作为多媒体系统模型。这种模型便于描述和分析并行媒体流间的同步问题。文中提出了时间层次同步和同步时间差阈值等概念。同步时间差同步是时间层次同步性能的一个度量。根据实现时间层次同步的可能性,一个时问Petri网中的同步变迁可划分为三种类型：理想同步变迁、可实现有效同步的变迁和不可能实现有效同步的变迁,一个好的多媒体系统的时间Petri网模型不应存在第三类同步变迁。文中给出了这三类变迁的判定条件。     

集成多媒体文件系统模型研究

目前的文件系统大多是单一类型的文件系统,或者采用尽力服务策略优化文本文件的服务,或者采用资源预留策略优化连续媒体的实时服务,而不能同时满足不同服务类型访问不同类型数据的需要。随着计算机计算能力、存储部件性价比的提高,以及计算机网络的不断发展,应用系统越来越大、越来越复杂,需要同时包含不同的应用类型和同时访问不同类型的数据。文中通过分析典型的应用类型和数据类型的特点,归纳出集成多媒体文件系统应具备的功能,并提出了实现集成多媒体文件系统的层次模型。