长江干线上浏段数字航道系统应用经验总结

本文介绍了上浏段数字航道系统功能,依据数字航道试运行总体情况,总结了系统的具体应用;提出系统应用的主要制约因素,重点探讨了数字航道运行模式下支撑体系的主要内容;并分析了未来应用的主要发展方向,旨在为数字航道的长期稳定运行提供经验及思路。     

浅谈高等级公路路面整修的质量控制

结合沪杭高速公路路面整修施工实践，从老路面病害处理、SBS改性沥青罩面施工面方面阐述了高等级公路路面整修施工过程中的处理方法和质量控制要点。     

基于未确知理论的工程风险评价模型研究

对于施工企业工程风险的控制越来越重要,但关于工程风险的研究,我国还处在初级阶段。本文基于未确知理论建立了施工企业风险评价模型,并通过信息熵确立指标的分类权重,明显优于过去常用的AHP确定权重的主观判断方法,具有较好的科学性和实际应用价值。     

沪杭高速公路路面整修施工的质量控制

结合沪杭高速公路路面整修施工实践，从老路面病害处理、SBS改性沥青罩面施工两方面阐述了高等级公路路面整修施工过程中的处理方法和质量控制要点。     

高等级公路路面整修的质量控制

文中结合沪杭高速公路路面整修施工实践，从老路面病害处理、SBS改性沥青罩面施工两方面阐述了高等级公路路面整修施工的质量控制要点。     

A New Region-of-interest Coding Method to Control the Relative Quality of Progressive Decoded Images

Based on the ideas of controlling relative quality and rearranging bitplanes, a new ROI coding method for JPEG2000 was proposed, which shifts and rearranges bitplanes in units of bitplane groups. It can code arbitrary shaped ROI without shape coding, and reserve almost arbitrary percent of background information. It also can control the relative quality of progressive decoded images. In addition, it is easy to be implemented and has low computational cost.     

Audio Video Compression Stream Synthesis and Implementation

Multiplex of digital streams is one of the key technologies in audio-video communication, and determines audio-video quality. A design scheme for an MPEG2 compliant digital television system including audio-video encoding and multiplexing was implemented. The principles and elements of system layer stream synthesis were analyzed. The key technologies of video and audio PES packetization were discussed, such as stream structure,scheduling matching, audio-video synchronization, data flow and buffering. DSP and FPGA are combined to construct header information and packet structure. The substitution of traditional RAM or PLD results in high operational efficiency and saves memory space. A scheduling algorithm was introduced for PES coding, using the monitor information of PES buffers. DTS is generated by multiplexer to guarantee synchronization. The system is not only simple but also stable, and maintains synchronization constraints of the standard. It supports both analogy and digital audio-video source input, and provides real-time MPEG2 compliant TS/PS output. It has perfect performance and meets the national broadcasting requirements.