自适应宏块编码算法的研究

通过对H.264/AVC宏块编码类型空域相关性的大量实验分析,发现经过率失真优化而确定的宏块编码类型无论是I帧、P帧和B帧,在空间域上都具有极强的相关性。提出了采用区域方差来度量宏块编码类型的空域复杂性,并根据宏块的这些空域复杂性制定出宏块类型预测的准则。依照该预测准则,给出了一种基于宏块类型空域预测的自适应宏块编码快速算法,并在H.264/AVC验证模型JM7.6上实现。大量的实验表明,采用宏块类型空域预测的自适用宏块编码算法,减少了H.264/AVC率失真优化算法的大量无效遍历,在保持图像编码质量和压缩效率基本不变的情况下,视频图像编码速度提高了4%~33%,在一定程度上克服了H.264/AVC率失真优化算法速度慢的缺陷。     

广州轨道交通五号线盾构施工关键技术

研究目的：解决广州轨道交通五号线盾构施工面临的诸多难题，总结在复合地层中盾构施工的若干经验，为类似工程提供借鉴。研究方法：通过工程类比、现场试验及监测等手段，对盾构施工相关工法、材料及技术等进行了引进、研究和实践。研究结果：广州地铁五号线大坦沙南-中山八站盾构区间首次成功应用了盾构始发SEW工法，并完成江中超浅埋泥水盾构过江掘进；火车站-小北站盾构区间顺利通过溶洞群，填补该项国内空白；动物园站-杨箕站盾构区间超小曲线半径掘进技术实现了新的突破；车陂南站-东圃站盾构区间首次成功应用了TAC高分子聚合物，辅助盾构顺利通过浅埋砂层。研究结论：广州地铁五号线盾构施工关键技术，有效控制了土体稳定和变形，在环境岩土工程问题防治方面取得了较大进步。     

城市轨道交通列车驾驶仿真器研究

城市轨道交通列车驾驶仿真器是城市轨道交通部门进行技能培训的高科技设备,能够进行精确的列车操纵性能仿真和逼真的列车驾驶环境仿真。基本功能包括模拟操纵功能、列车动力学计算功能、故障判断培训功能、视景和声音仿真功能以及运动仿真功能。针对城市轨道交通特点,给出了轨道交通列车驾驶仿真器的运行仿真数学模型,提出采用分布式计算机体系结构、MPEG视频压缩技术和基于DirectSound技术的多媒体声音系统,设计具有4层5自由度液压运动平台的驾驶仿真器。并基于以上技术完成了北京地铁交流传动电动客车列车驾驶仿真器的研制,成功应用于北京地铁技术学校学员和北京地铁司机的教育培训。     

多孔PZT95/5压电陶瓷性能的研究

本次实验主要研究在制备过程中加入抑制剂、PEG、胶凝剂等对PZT95／5粉体的影响,此外,研究了掺杂物(铌盐)的掺入方式及加入量对PZT95／5粉体性能的影响。     

基于AUTOCAD的电气原理图综合系统的开发

为能实现电气图纸信息的数字化，将传统的AUTOCAD绘图方式与CADDS5电气设计进行了较好的融合，从而实现了在AUTOCAD环境下绘制电气原理图，取代了在CADDS5电气模块中原理图繁琐的输入环节。     

集装箱码头计算机模拟模型概况

简要介绍了计算机模拟技术以及它在港口工程方面的应用。特别是针对几家国外咨询公司开发的集装箱码头的模拟模型，分别讨论了它们的特点和应用范围。最后结合例子，介绍了一航院CTSS模型的概况。     

The importance of Öresund and the Drogden Sill for Baltic inflow

Based on high resolution current and salinity measurements from the Flinten and Drogden Channels, this paper assesses the relative importance of major Baltic inflows on ‘everyday' flow conditions of highly saline water (S>17 PSU) through the Öresund for a period of 43 months. During years with no major Baltic inflows, 1994–1996, it is found that the Öresund on average supplies 1.2 Peta-grams (Pg) of salt net/year to the Baltic, while inflow above 17 PSU is in the order of 2.3 to 4.0 Pg/year. Sixty percent of this inflow is in the salinity range 17–23 PSU; the remainder has a higher salinity. It is, thus, concluded that normal and regularly occurring flow in the Öresund plays a much larger role in supplying salt to the Baltic than is usually assumed.     

基于身份与位置分离体系结构的列车通信方案研究

在传统的互联网体系结构中,IP地址既作为节点的位置标志又作为节点的身份标志,难以适应列车通信。针对这一问题,提出身份与位置分离体系结构,并设计一种列车通信方案。在基于身份与位置分离体系结构的列车通信方案中,IP地址只作为节点的位置标志,引入端点标志符作为节点的身份标志,使得节点移动时也不会中断连接。列车中的节点通过移动网关接入互联网,对于MANET节点发送给互联网节点的数据报文,移动网关在转发之前需要对该数据报文重新封装;当节点移动时,利用路由更新选项和路由确认选项进行路由更新,并且这些选项都封装在IPv6逐跳选项报头中,不需要额外的信令开销。性能仿真及分析表明,与基于MIPv6的通信方式相比,该方案具有更高的报文递交率以及更低的报文开销。     

The small-sized benthic biota of the Håkon Mosby Mud Volcano (SW Barents Sea slope)

R/V POLARSTERN expedition ARK XVIII/1 in summer 2002 provided the opportunity to carry out a sampling programme to assess the activity, biomass and composition of the small-sized benthic biota (size range: bacteria to meiofauna) around the active mud-oozing and methane-seeping Håkon Mosby Mud Volcano (HMMV) on the SW Barents Sea slope, Northern North-Atlantic. A total of 11 stations, covering different areas (e.g., bacterial mat sites, and pogonophoran fields) within the crater, and sites outside the caldera were sampled using a multiple corer. Subsamples were analyzed for various biogenic compounds to estimate the flux of organic matter to the seafloor (sediment-bound chloroplastic pigments indicating phytodetritus), activities (bacterial exo-enzymatic turnover rates) and the total biomass [from bulk parameters, like phospholipid (PL) concentrations in the sediments] of the smallest sediment-inhabiting organisms (range: bacteria to meiofauna). Direct investigations of bacterial numbers and biomasses as well as on meiofauna densities and composition completed our investigations at HMMV. As expected for a comparable small deep-sea area with only minor disparity in water depth between sampling sites, our investigations revealed generally no significant differences in organic matter input from phytodetritus sedimentation between sampling sites inside and outside HMMV. Bacterial exo-enzymatic activities as well as total microbial biomass (TMB) and meiofauna densities, however, exhibited generally higher values at HMMV, compared to sites outside the mud volcano. Enhanced benthic life at HMMV is based on chemosynthetic processes, making the mud volcano a “chemosynthetic oasis” in an otherwise oligotrophic deep-sea environment. As we did not find any indication for bacterial symbioses in the meiofauna, comparably rich meiofaunal assemblages at HMMV are presumably indirectly related to a general enhanced biological production.     

AlSi5钎料在Q235钢板上的铺展试验研究

采用TIG电弧钎焊试验方法，研究了在TIG电弧加热条件下，焊接参数变化对Al-Si钎料在Q235钢板上润湿、铺展行为的影响，结果表明燃弧时间和电流的增加，或弧长在一定范围内增加皆有利于AlSi5钎料在Q235钢板上的润湿和铺展；另外添加合适钎剂对提高AlSi5钎料铺展性能有利；同时表明交流电源时，由于正负极在不断变化，可导致Q235钢板上的氧化膜破坏，使钎料得到良好铺展。