以一种新的距离度量作为反馈的相关跟踪方法

基于相关的模板匹配方法在图像跟踪中得到了广泛的应用,但是这种方法的主要缺点是对图像噪声非常敏感,而且由这种方法得出的相关曲面比较平坦。为了有效抑制噪声和局部遮挡对图像的影响,提出用鲁棒统计中的一个值代替相关值作为距离度量。它不是计算两幅图像的对应像素差值,而是计算两幅图像中差别不大的对应像素对的个数。实验证明这样得到的曲面相对　　收稿日期:2003 08 31;　修订日期:2003 10 28作者简介:张桂林(1944 ),男,天津人,教授,博士生导师,主要研究方向为自动识别、人体生物统计特征识别、图像处理算法与系统性能评估等。　　　　　　　要尖锐得多。当上述的距离度量应用于跟踪过程中时,模板的合理更新对跟踪非常重要。基于上述的距离度量方法,提出了一种新的模板更新策略。利用两幅图像中近似像素在整修匹配模板像素中所占的比例大小决定加权系数。这种加权策略可以自适应地根据图像序列的变化选择更新相关模板,同时在一定程度上减小模板漂移的危险。     

Simultaneous Measurement of Viscosity and Density with an Oscillating-Disk Instrument: The Effect of Fixed Plates

The period and damping of the free motion of a body oscillating in a fluid depend on the fluid's viscosity and density. Commonly, a working equation which expresses the damping as a function of the viscosity and density is solved for the viscosity, the damping being measured and the density being treated as an independently supplied parameter. Another working equation exists for the period, and, in general, the period depends on a combination of the viscosity and the density which is linearly independent of the combination that appears in the damping equation. It is, therefore, in principle, possible to determine both the viscosity and the density by a simultaneous solution of the two coupled working equations, since the period also is measured. In this paper, the working equations that describe the oscillating-disk viscometer are reviewed and their simultaneous solution is considered. The effect of fixed plates symmetrically located above and below the oscillating disk is of specific interest. The paper's main result is that fixed plates can dramatically increase the independence of the damping and period working equations, so that it becomes indeed feasible to determine the viscosity and the density of a fluid simultaneously from the damping and period of oscillating motion. A price is paid, however, because the instrument's working equations when plates are present have multiple solutions. Under special conditions, these multiple solutions can coalesce, and then one can only deduce the viscosity from the damping equation if the density is known a priori.     

单向实时数字视频传输中帧同步锁定技术研究

提出一种适用于单向实时数字视频传输系统的帧同步锁定方案。其方法在接收端采用本地参考时钟、状态机、锁相环，并结合CIMT编码方式实现系统自动维持帧同步锁定，而无需周期性加入帧同步码。对该帧同步锁定方案与周期性加入帧同步码强制锁定方案进行性能比较．并将其应用到单向实时数字视频光纤传输系统中。实验证明，系统自动实现帧同步锁定的方案是单向实时数字视频传输系统实现帧同步锁定的最佳方案。     

嵌入式RISC核MPEG2/AC3解码器

介绍了在一个嵌入RISC核的AC3／MPEG2音／视频解码器中，通过增加特殊指令及其相应的硬件逻辑，对AC3的音频解码进行了一定的改进，不仅达到了AC3解码的实时性要求，而且降低了对存储器的要求。     

大坝监测自动化中的人工比测研究

阐述了人工比测的概念、方式和数据分析方法,对人工比测及数据分析中应注意的问题也进行了深入研究。     

Improving the Calibration of Vacuum Gas Flow – Control Leak Gauges

A new and original method of calibrating helium leaks that makes it possible to take into account the existence of a number of auxiliary phenomena is described. For this purpose, a hollow leak the purpose of which is to reproduce only desorbed gas flows, is introduced into the vacuum system of the calibration bench. Analysis of the results of corresponding cumulation measurements makes it possible to introduce corrections for these phenomena.     

Measurement and Identification of the Parameters of SPICE-Models of a Bipolar Transistor

A method of measuring and identifying the static parameters of a bipolar transistor is considered. The characteristic of the transistor, from which the parameters of the model are determined, is chosen depending on what group the calculated parameters belong to. The characteristics are measured in such a way that the equations of the model describing them can be reduced to the simplest form.     

实时Motion JPEG2000视频编码系统设计

介绍了基于ADV202 JPEG2000编码芯片的Motion JPEG2000视频编码系统,该系统可实现SMPTE274M的实时编码,支持失真/无失真编码,与标准完全兼容.给出了系统硬件结构和软件流程设计,提出了一种利用帧间相关性减少编码计算量的码率控制方法.     

连续波雷达测距中的解模糊技术

研究连续波雷达测距中的距离模糊问题，分析几种常用解模糊方法的性能，并讨论参差比的选取对测距范围的影响。     

基于SIP的宽带实时多媒体通信研究与实现

介绍了会晤创建协议(SIP)，提出了基于SIP的应用系统——SRMCS，针对该实时多媒体通信系统，分析了其音频模块的实现和背景噪音的处理、视频模块的实现和视频的流畅播放，并就实时多媒体通信系统的关键问题——视、音频同步给出了可行的解决方案，最后还探讨了本系统中信令流和媒体流的传输方式。