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
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
航空电子网络上音视频应用的需求日益剧增,对网络的带宽及服务质量都提出了更高的要求。音视频传输AVB(Audio Video Bridge)以太网络在传统以太网上提供时间同步和低延迟的音视频流服务,因而受到航电应用的关注。分析了AVB协议,针对航...航空电子网络上音视频应用的需求日益剧增,对网络的带宽及服务质量都提出了更高的要求。音视频传输AVB(Audio Video Bridge)以太网络在传统以太网上提供时间同步和低延迟的音视频流服务,因而受到航电应用的关注。分析了AVB协议,针对航电环境下信息交换需解决的问题,提出了时间触发AVB网络方案,研究了其实时性传输机制和流量映射等模型;结合某综合航电系统的案例,构建了AVB网络的系统架构,仿真结果表明时间触发AVB网络有望满足分布式综合模块化航空电子(DIMA)系统实时性需求,并且比AFDX网络具有优越性。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.
文摘航空电子网络上音视频应用的需求日益剧增,对网络的带宽及服务质量都提出了更高的要求。音视频传输AVB(Audio Video Bridge)以太网络在传统以太网上提供时间同步和低延迟的音视频流服务,因而受到航电应用的关注。分析了AVB协议,针对航电环境下信息交换需解决的问题,提出了时间触发AVB网络方案,研究了其实时性传输机制和流量映射等模型;结合某综合航电系统的案例,构建了AVB网络的系统架构,仿真结果表明时间触发AVB网络有望满足分布式综合模块化航空电子(DIMA)系统实时性需求,并且比AFDX网络具有优越性。
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。
