An audio and video network monitoring system for weather modification operation transmitting information by 3G, ADSL and Internet has been developed and applied in weather modification operation of Tai'an City. The a...An audio and video network monitoring system for weather modification operation transmitting information by 3G, ADSL and Internet has been developed and applied in weather modification operation of Tai'an City. The all-in-one machine of 3G audio and video network highly integrates all front-end devices used for audio and video collection, communication, power supply and information storage, and has advantages of wireless video transmission, clear two-way voice intercom with the command center, waterproof and dustproof function, simple operation, good portability, and long working hours. Compression code of the system is transmitted by dynamic bandwidth, and compression rate varies from 32 kbps to 4 Mbps under different network conditions. This system has forwarding mode, that is, monitoring information from each front-end monitoring point is trans- mitted to the server of the command center by 3G/ADSL, and the server codes'and decodes again, then beck-end users call images from the serv- er, which can address 3G network stoppage caused by many users calling front-end video at the same time. In addition, the system has been ap- plied in surface weather modification operation of Tai'an City, and has made a great contribution to transmitting operation orders in real time, monitoring, standardizing and recording operating process, and improving operating safety.展开更多
采用Flash Media Server流媒体服务器技术,基于TCP/IP和RTMP协议,设计开发了远程视频教学系统,介绍了该系统在线视频教学功能、电子白板教学功能、视频录制与点播功能和在线答疑教学功能的设计与实现方法,最后采用Fiddler软件对其进行...采用Flash Media Server流媒体服务器技术,基于TCP/IP和RTMP协议,设计开发了远程视频教学系统,介绍了该系统在线视频教学功能、电子白板教学功能、视频录制与点播功能和在线答疑教学功能的设计与实现方法,最后采用Fiddler软件对其进行功能测试.结果显示,该系统具有良好的实时性和稳定性,不仅增强了网络教学过程中的交互性与实时性,同时也为网络公开课程的进一步发展提供了技术思路与方案借鉴.展开更多
为更好的构建远程教育平台,解决目前所面临的技术难题,开发低成本、高效率的远程教育系统成为市场的一大热点,FLASH公司推出的Flash Media Server2技术为实现这一目标提供了强有力的支持,应用该技术可以开发出功能完善、易于操作、成本...为更好的构建远程教育平台,解决目前所面临的技术难题,开发低成本、高效率的远程教育系统成为市场的一大热点,FLASH公司推出的Flash Media Server2技术为实现这一目标提供了强有力的支持,应用该技术可以开发出功能完善、易于操作、成本较低的远程教育系统。展开更多
Over the past years, we have witnessed an explosive growth in the use of multimedia applications such as audio and video streaming with mobile and static devices. Multimedia streaming applications need new approaches ...Over the past years, we have witnessed an explosive growth in the use of multimedia applications such as audio and video streaming with mobile and static devices. Multimedia streaming applications need new approaches to multimedia transmissions to meet the growing volume demand and quality expectations of multimedia traffic. This paper studies network coding which is a promising paradigm that has the potential to improve the performance of networks for multimedia streaming applications in terms of packet delivery ratio (PDR), latency and jitter. This paper examines several network coding protocols for ad hoc wireless mesh networks and compares their performance on multimedia streaming applications with optimized broadcast protocols, e.g., BCast, Simplified Multicast Forwarding (SMF), and Partial Dominant Pruning (PDP). The results show that the performance increases significantly with the Random Linear Network Coding (RLNC) scheme.展开更多
为有效解决现代远程教育中网络教学软件的实用性问题,分析了这一类软件的特点,并综合考虑服务器带宽、数据传输方式、实时性等因素,提出了基于Client/Server架构模式、产品功能模块化的面向应用型软件设计方案,实现了具有视频音频、电...为有效解决现代远程教育中网络教学软件的实用性问题,分析了这一类软件的特点,并综合考虑服务器带宽、数据传输方式、实时性等因素,提出了基于Client/Server架构模式、产品功能模块化的面向应用型软件设计方案,实现了具有视频音频、电子白板、PPT课件教学、文字交流等功能的实时远程网络教学软件的设计,软件采用Visual C++ 2008进行开发。测试结果表明了该软件的功能和实用性。展开更多
基金Supported by the Integration and Application Project of Meteorological Key Technology of China Meteorological Administration(CMAGJ2012M30) Technology Development Projects of Tai'an Science and Technology Bureau in 2010 (201002045) and 2011
文摘An audio and video network monitoring system for weather modification operation transmitting information by 3G, ADSL and Internet has been developed and applied in weather modification operation of Tai'an City. The all-in-one machine of 3G audio and video network highly integrates all front-end devices used for audio and video collection, communication, power supply and information storage, and has advantages of wireless video transmission, clear two-way voice intercom with the command center, waterproof and dustproof function, simple operation, good portability, and long working hours. Compression code of the system is transmitted by dynamic bandwidth, and compression rate varies from 32 kbps to 4 Mbps under different network conditions. This system has forwarding mode, that is, monitoring information from each front-end monitoring point is trans- mitted to the server of the command center by 3G/ADSL, and the server codes'and decodes again, then beck-end users call images from the serv- er, which can address 3G network stoppage caused by many users calling front-end video at the same time. In addition, the system has been ap- plied in surface weather modification operation of Tai'an City, and has made a great contribution to transmitting operation orders in real time, monitoring, standardizing and recording operating process, and improving operating safety.
文摘采用Flash Media Server流媒体服务器技术,基于TCP/IP和RTMP协议,设计开发了远程视频教学系统,介绍了该系统在线视频教学功能、电子白板教学功能、视频录制与点播功能和在线答疑教学功能的设计与实现方法,最后采用Fiddler软件对其进行功能测试.结果显示,该系统具有良好的实时性和稳定性,不仅增强了网络教学过程中的交互性与实时性,同时也为网络公开课程的进一步发展提供了技术思路与方案借鉴.
文摘Over the past years, we have witnessed an explosive growth in the use of multimedia applications such as audio and video streaming with mobile and static devices. Multimedia streaming applications need new approaches to multimedia transmissions to meet the growing volume demand and quality expectations of multimedia traffic. This paper studies network coding which is a promising paradigm that has the potential to improve the performance of networks for multimedia streaming applications in terms of packet delivery ratio (PDR), latency and jitter. This paper examines several network coding protocols for ad hoc wireless mesh networks and compares their performance on multimedia streaming applications with optimized broadcast protocols, e.g., BCast, Simplified Multicast Forwarding (SMF), and Partial Dominant Pruning (PDP). The results show that the performance increases significantly with the Random Linear Network Coding (RLNC) scheme.
文摘为有效解决现代远程教育中网络教学软件的实用性问题,分析了这一类软件的特点,并综合考虑服务器带宽、数据传输方式、实时性等因素,提出了基于Client/Server架构模式、产品功能模块化的面向应用型软件设计方案,实现了具有视频音频、电子白板、PPT课件教学、文字交流等功能的实时远程网络教学软件的设计,软件采用Visual C++ 2008进行开发。测试结果表明了该软件的功能和实用性。