广东省防汛卫星移动通信系统的设计与实现

利用卫星通信,结合3G/4G蜂窝移动通信,设计并实现广东省防汛指挥应急调度卫星移动通信系统。系统由现场视频手机、蜂窝3G/4G移动通信和卫星BGAN网络、指挥中心自动视频接收播放终端组成,已在广东省防汛应急指挥调度中应用,现场人员通过高速3G/4G移动或卫星通信安全接入广东省水利信息网络系统,可以随时随地传送现场视频和进行会商指挥调度,对提升全省三防应急会商决策、指挥调度的效率有重要的推动作用。     

支持无线网络的实时视频监控系统设计

为了解决有线网络视频监控的布线问题和工作人员的移动化监控问题,设计并实现了一种支持IP摄像头、DVR、3G手机作为视频数据采集前端,兼容H.264和MPEG4等编码标准和支持PC和3G手机进行客户端监看的实时视频监控系统,该系统实现视频的采集、压缩、传输、解码、显示、控制、录像、事件通知、电子地图等功能,该系统支持前端采集设备的多流输出和高并发访问,适应了3G手机的带宽,提高了服务器使用效率,达到了利用手机进行移动视频监控的目的。     

基于oRTP库的无线语音视频直播系统的设计

随着3G和4G网络的全面覆盖,通信网络的带宽大大增加,另外,智能终端(Android,iPhone等)快速普及,使得无线语音视频直播的广泛应用成为可能。设计了一种基于开源oRTP库的无线语音视频直播系统。给出了系统的总体结构,在描述了iOS系统实现语音和视频采集的方法后,重点介绍了基于oRTP库的语音和视频传输部分的设计思路和程序实现,并给出了关键部分的实现代码,简要介绍了客户端如何实现直播语音和视频。通过测试,手机端处于WiFi和3G环境下,该系统具有较好的QoS性能,和良好的可靠性。实验证明,无线语音直播应用已具备应用和推广的初步条件。     

基于Darwin的多平台多用户直播、点播系统设计

针对当前多平台多用户播放手机客户端直播、录像视频的需求,提出了一种手机移动客户端主动推送视频流到Darwin服务器直播、转播及录制供多平台多用户播放的解决方案。利用开源的流媒体服务器Darwin结合开源库mp4v2实现将手机客户端上传的视频流实时转发和录制;PC平台客户端由开源RTSP架构live555结合开源编解码库ffmpeg实现视频直播、点播播放。Web平台客户端由Html5技术实现视频点播,由插件实现直播。实验结果表明,该方案在现有的3G网络上具有较高的实时性和稳定性,视频具有较好的质量,能满足多平台多用户视频直播、点播播放的要求。     

基于3G网络的手机移动视频监控系统的设计

为了解决传统固定视频采集实时传输系统的布线问题和基于GPRS/EDGE无线网络的远程视频传输系统的带宽问题,采用3G手机作为视频数据采集前端,在简述了H.264编码标准和RTP/RTCP协议原理的基础上提出一种基于3G网络的手机移动视频监控系统,并给出了硬件和软件的框架;最后,介绍了一些编写视频传输程序的方法。实验表明:在具体的设置特殊环境下达到了视频采集和实时传输的效果。     

基于crtmpserver的手机直播系统

分析现有视频直播方案,提出一种基于开源视频库FFmpeg和流媒体服务器crtmpserver的手机视频直播系统解决方案.在手机端利用FFmpeg进行编码压缩和流传输;在服务器端利用crtmpserver和nginx进行转发、存储和管理;在PC端利用FFmpeg接收视频流并解码播放,通过HTTP方式实现视频回放.实验结果表明,该方案在现有联通和电信的3G网络上具有较高的实时性和稳定性,且丢包率低,视频具有较高的质量.     

基于3G/4G多旋翼飞行器的视频传输系统 基于3G/4G多旋翼飞行器的视频传输系统

为解决各行业进行高空拍摄时投入高、效果差,无法实时察看地面情况等问题,提出一种基于 STM32微控制器的3G/4G多旋翼飞行器的视频传输系统解决方案。系统由多旋翼飞行器、3G/4G网络视频传输系统和地面智能手机控制平台等构成。试验表明,本方案通过3G/4G网络实现视频的传输,能够实现高空拍摄、视频传输、手机接收等功能,具有较好的实时性和可控性。     

基于3G/4G多旋翼飞行器的视频传输系统

为解决各行业进行高空拍摄时投入高、效果差,无法实时察看地面情况等问题,提出一种基于STM32微控制器的3G/4G多旋翼飞行器的视频传输系统解决方案。系统由多旋翼飞行器、3G/4G网络视频传输系统和地面智能手机控制平台等构成。试验表明,本方案通过3G/4G网络实现视频的传输,能够实现高空拍摄、视频传输、手机接收等功能,具有较好的实时性和可控性。     

泰德收购Ivigo 实现终端视频通信

7月6日,泰德公司宣布收购互动多媒体视频设备的领先供应商及3G手机视频服务开发商Ivigo,通过结合泰德的Expressway技术,实现3G手机可与任何地点的视频终端实现视频通讯。Ivigo的视频网关通过结合泰德Expressway穿越网络防火墙技术,可帮助3G手机用户从办公室、路上、旅馆房间、机场等任何地点接入任何集体或个人的视频系统。此3G视频网关将是这次收购后的首款产品,将重要面向3G移动运营商、视频服务供应商和企业销售。此外,该3G视频网关还将3G手机与全球商务视频系统和设施所使用的SIP、IP、ISDN网络相连接。用户在3G手机上拨一个号…     

4G时代看流畅直播凤凰视频6．5版本评测

近日,4G牌照发放的喜讯被众专家解读,民间高手更是借此大大过招。自此,WiFi不再是人的第一需要。业内人士表示：用户网速的快速提升,将带来网络视频等一系列高带宽高流量应用的进一步普及,4G时代就是移动短视频时代!凤凰视频客户端搭乘4G高速列车全新改版的V6．5安卓版,推出最新功能：全国数十家卫视频道直播全面上线!手机上的电视台,走到哪里看到哪里。小伙伴们再也不用为直播不畅、流量费爆棚担心啦!     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.