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1.
数字权限描述语言及其比较研究   总被引:5,自引:0,他引:5  
本文在对几种数字权限描述语言如XrML(Extensible Rights Markup Language,可扩展权限标记语言)、ODRL(Open Digital Right Language,开放的数字权限语言)、MPEG-21 REL(MPEG-21的第五部分——数字权限描述语言)、OMA(Open Mobile Alliance)DRM-REL、OeBF(Open e-Book Forum)REL进行了介绍,对ODRL和MPEG-21 RE进行了对比分析,提出教育领域内的数字权限描述语言应该简洁易用、易扩展。  相似文献   

2.
MPEG-2l多媒体框架是正在制订中的关于多媒体信息发布和使用的国际标准。它是一个支持通过异构终端和网络,使用户透明地、广泛地、交互地使用多媒体信息资源的综合性的技术标准。本文简要的介绍了MPEG-21多媒体框架标准的研究目标和用户需求,阐述了MPEG-21多媒体框架标准的基本要素,最后重点讨论了MPEG-21在教育教学中的应用。  相似文献   

3.
本文简要介绍了MPEG系列的MPEG-1,MPEG-2,MPEG-7和MPEG-21的特点,并重点介绍了MPEG-4和最新的MPEG-A的特点和应用。  相似文献   

4.
当今各类多媒体信息正在世界范围内快速增长.越来越多的信息是以数字形式、在线形式以及诸如静止图像、图形、3D模型、声频、语音、视频等形式出现。MPEG-7标准(多媒体内容描述接口)将为各类多媒体信息提供一种标准化的描述,这种描述与内容本身有关,允许快速和有效地查询用户感兴趣味的资料。  相似文献   

5.
吴涛 《丽水学院学报》2004,26(2):66-67,72
作为新一代的视、音频压缩标准,MPEG-4不仅比MPEG-1和MPEG-2有更高的压缩比,更低的带宽要求,而且其基于对象的技术能实现内容上的对象互动。这将为网络信息交流带来革命性的变化,对人们的工作和生活将产生深远的影响。着重介绍MPEG-4标准的特点以及在校园网中的典型应用。  相似文献   

6.
根据经合组织(OECD)最新进行的一项调查,韩国是目前为止宽带互联网接入应用普及率最高的国家。 该组织对30个成员国的宽带使用情况进行了调查,结果显示:韩国以10%的比例居首位(用户总数达430万),而加拿大和美国分别以4%和3%的比例位居第二和第三,其后是奥地利(低于2%)、荷兰、比利、时。令人惊讶的是,作为欧洲电子商务中心的英国却排在第21位;欧洲经济增长最快的爱尔兰则排名第26位。 调查指出,韩国地区宽带接入的发展是有线电视电缆线路与数字用户线路(DSI)接入服务之间激烈竞争的结果;而其他各国在本地环路服务定价上的缓慢进展阻碍了宽带接入的应用  相似文献   

7.
21世纪是信息的社会,在信息社会中拥有最新的,最完整的,最可靠的信息是相当重要的,建立能提供最新信息,模拟现实的“数字地球”系统是必要的,随着航天技术和计算机技术及遥感技术的发展,全球定位系统(GPS)、遥感(RS)、地理信息系统(GIS)的一体化步伐越来越快,使“数字地球”系统的出现成为了可能,而区域性(省级)数字系统的建立是建立“数字地球”的基础,所以,建立“数字区域”是相当重要的,本文用系统论的观点,方法和面向对象的方法,分析了建立“数字陕西”信息系统(DSXIS)的发要性和可能性,进行了用户需求分析和系统可行性分析,设计了适合用户的系统总体结构,数据库和系统功能。  相似文献   

8.
青松E视数字化电子考场是集考场监控、考场广播、录像取证、网络视频会议、教学观摩评估、校园安全防范、交互多媒体网络教学等于一体的综合网络系统。该电子考场采用DPS有盘技术、分布式录像、电子水印等数字处理技术,充分保障考试安全性。先进的MPEG-4硬件压缩及组播传输方式,保  相似文献   

9.
基于RTP协议的MPEG-4视频传输系统的设计与实现   总被引:3,自引:0,他引:3  
本文在简单介绍RTP协议和MPEG-4视频格式的基础上,分析了用于MPEG-4视频实时传输的RTP数据负载格式,详细说明了MPEG-4视频RTP负载格式的定义和切分原则,以及最终系统的设计和实现方法。  相似文献   

10.
图像压缩存储技术和网络传输技术,是数字化监控系统的两大关键技术。目前监控系统的市场需求在日益扩大.监控产品市场份额不断增长,数字监控市场呈现空前繁荣的景象。本文结合近年来数字监控产品的应用情况,对比介绍了监控系统在国外和国内的发展状况.以及各个发展阶段的代表产品;详细分析了数字化监控产品特别是DVR产品的技术标准和现状;探讨了数字监控产品的发展趋势和技术上的发展方向。随着高清晰度和MPEG-4的图像压缩标准的应用,数字化监控将迈向一个新的时代。  相似文献   

11.
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.  相似文献   

12.
汉字倒说     
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。  相似文献   

13.
风的曲线     
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.  相似文献   

14.
Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.  相似文献   

15.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

16.
一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/  相似文献   

17.
《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?  相似文献   

18.
钱生钱!     
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了  相似文献   

19.
Different nations have different social cultures, and the social culture of every nation is developing with the development of the nation, language is greatly influenced by social culture, which enables language to possess national and historical characteristics. Word is the smallest, independent, meaningful linguistic unit of language. It can well reflect the national and historical characteristics. From synchronic aspect, the social and cultural influence on word meaning is mainly embodied in conceptual and associative meanings of word. The incorrespondence of word meaning is a phenomenon that exists in both conceptual and associative meanings of word among different languages. From diachronic aspect, the development of social culture causes some changes of word meaning to some extent. Therefore, social culture plays a key role in vocabulary learning and mastery of a language.  相似文献   

20.
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.  相似文献   

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