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.     

港航联动又拓版图

6月12日晚,上海国际港务（集团）股份有限公司（下称上港集团）宣布,上海同盛投资（集团）有限公司（下称同盛投资）拟将持有的上港集团34．76亿股,以5．45元／股协议转让给中国远洋海运集团有限公司（下称中远海运）,涉及金额约189．4亿元。     

港口雄开万里奔流 智慧赋能向海而兴

10年来我国港口事业发展取得了历史性成就。港口规模稳居世界第1,自动化集装箱码头和大型干散货码头技术水平世界领先。我国正由港口大国不断向港口强国加速迈进,而科技创新已经成为我国港口发展的核心驱动力。中国港口开启自动化发展新纪元。2016年,厦门远海自动化码头建成并投产,这是中国港口人在集装箱自动化码头领域的首次探索。     

渗透球壳流固耦合问题的位移及内力解

在弹性薄壳的线性(非线性)理论和流体力学基本方程的基础上,在小雷诺数的情况下应用相容欧拉-拉格朗日法建立了渗透球壳在流体中流固耦合的基本方程及关系式,并通过摄动法求解了渗透球壳在粘性流体中的流函数从而进一步解出其位移及内力解.通过具体算例,给出了壳的位移变形及内力图,并对有关参数进行讨论,绘出相关曲线.得出渗透系数k和流速越大的情况下,壳体位移也就越大,相应的内力也变大;球壳在三个角度处位移为零.文章能为过滤器问题提供指导.     

柔性艉鳍推进装置的机构综合与优化设计

根据柔性艉鳍推进装置所须达到的性能特性要求，本文对该装置进行了机械综合与优化设计，以改善其水动力性能，人推进效率。     

广东省沥青混凝土拌和站布局规划研究

从合理地布局拌和站、避免造成重复建设和资源浪费、提高设备利用率的角度出发，分析广东省沥青混凝土拌和站布局影响因素及布局原则。构建拌和站布局规划模型，并在模型求解方法的基础上，得到广东省沥青混凝土拌和站布局规划，为拌和站物流系统的形成奠定了基础。     

地方公路收费站的撤销对高速公路交通量的影响

地方公路收费站的撤销，是各个地方对改善投资环境的有力措施，其影响是广泛的。将引起各条道路交通量的重新分布。对仍然收费的高速公路，其影响更大。但影响有多大，本文就佛山地区撤销地方公路收费站对广三高速、广佛高速和佛开高速的影响进行详细的分析说明。     

高强度低噪声球墨铸铁齿轮的性能评价

当前情况下,铁道车辆用传动齿轮噪声在驱动系统噪声中占有较高的比例.作者的研究小组正在开发以低成本实现齿轮低噪声的方法,也就是说不是通过加工以变更齿轮接触面的形状,而是有效利用齿轮材料的衰减特性.文章介绍了利用高强度球墨铸铁制作常规线路车辆用的齿轮.评价了该种齿轮振动与噪声性能,同时阐述了为确保与现有齿轮相同的强度,致力...