基于IP组播技术的视频监控系统

采用单播或广播传输方式的视频监控系统存在网络瓶颈问题。将IP组播技术应用到网络视频监控系统中,可以有效地节省网络资源,具有时延和网络阻塞几率小的优点。结合多媒体网络中视频传输系统的结构,给出了IP组播技术在视频监控系统中的设计思想与Winsock实现方法。建立监听套接字较好地保证了视频信息传输的实时性和QoS。试验中视频传输效果良好。     

校园网IP电话的设计与实现

为了实现基于校园网的语音通信,在现有网络设施基础上升级相应的语音模块和语音设备,设计校园IP电话通讯网络。首先介绍IP电话三种通讯方式,然后分析IP电话系统的结构模型,最后采用实例方法针对某大学的网络进行IP电话的设计与实现,并给出了详细的网络配置命令,结果表明基于校园网的IP电话设计是可行的。     

在线学习系统的研究与设计

随着网络技术和多媒体技术的迅速发展,通过网络远程在线学习的方式,已经成为现代教学的手段之一。本文介绍了在现代网络传输条件下,一个典型的在线学习系统的研究与设计。     

用流媒体技术实现网上在线课堂

目前的网络传输速度很低，对于体积庞大的多媒体件，在网络上传输存在诸多问题。应用流媒体技术在网络上传输多媒体件是目前使用的较先进的技术，它使得在网上观看丰富多彩的节目、网上在线课堂的实现成为可能。本阐述了“流”技术对网络多媒体的传输的重要意义，介绍了Windows Media系统的软硬件要求、工作原理及实现网上在线课堂的方法。     

在线辅导技术的选择、设计与支持:辅导教师技术维度的能力

在线辅导技术应用的效果是影响网络学习效果的重要因素之一。在实践中,我国辅导教师尚缺少在线辅导技术选择、设计和支持方法层面的明确指导。本文旨在明确辅导教师的技术角色定位,分析和探讨在线辅导技术选择、设计和支持的原则和方法。文章分为四个部分:第一部分明确在线辅导技术的选择和设计在网络在线辅导中的重要性,介绍辅导教师的技术职能;第二部分介绍网络在线辅导技术选择与支持的一般原则和方法以及同步在线辅导和异步在线辅导情境下技术的选择;第三部分和第四部分分别介绍同步和异步在线辅导技术的设计和支持。期望本文能够为辅导教师网络在线辅导技术选择、设计和支持方面提供指导和借鉴。     

TD-LTE语音解决方案的研究

TD-LTE语音解决方案主要有双待机、CSFB、VoLTE等。双待机的原理为在手机内置两个多模收/发模块,使手机同时驻留在2G/3G和TD-LTE网络,数据业务优先通过TD-LTE网络提供,若无LTE覆盖,则由2G/3G网络提供,语音业务则通过2G/3G网络提供。CSFB的原理为终端在LTE网络驻留,使用CS语音回退技术将TD-LTE网络语音服务转移至传统的2G/3G网络,通话结束后再返回到TD-LTE网络。VoLTE作为TD-LTE的最终语音解决方案,以Vo IP的方式通过LTE的分组域来传输语音业务相关数据包,直接使用TD-LTE网络来承载语音业务。     

一种自适应IP QoS机制的实现方案

提出了一种在IP网络中采用的自适应QoS机制。当系统资源不足以满足多媒体流的传输要求时,通过启用自适应函数对QoS进行动态管理,以解决以往的IP QoS模型中当系统的资源不足时,拒绝多媒体流的传输的情况。采用自适应IP QoS机制后,通过降低传输中比此多媒体流优先级低的多媒体流的QoS指标来释放系统资源,以满足该多媒体流传输的QoS指标。最后,对自适应IP QoS算法进行了仿真,并给出了仿真结果。     

未来IP网络承载多媒体业务的方向

目前,分布式多媒体应用包括语音、图形、图像、视频、动画等多种类型。其不仅对网络带宽有很高的要求,还要求信息传输低延迟和低抖动等,非连接IP网络“尽力而为”的业务模式已不适应未来网络需求。那么,未来IP网络承载多媒体业务该如何发展？     

PACS系统的关键技术及其发展前景

PACS系统的作用是使医学影像能够被网络用户在线使用，要做到这一点，关键是解决网络设计和技术研究两大问题，网络设计要实现物理层，应用层，管理／用户层方面模块设计，技术研究则要侧重于图像压缩传输、存储、搜索、可视化、安全性等方面的研究。     

《网页编辑》多媒体网络课件的设计与实现

本文探讨了《网页编辑》多媒体网络课件的系统结构和模块设计,重点分析了教学内容、实验指导、在线交流等关键模块的设计思路与技术实现,以期对更多的网络课件制作者提供参考借鉴。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

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/     

漏洞百出的教育

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?     

Western and Eastern culture differences in commercial field

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.     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

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.