人工心脏单自由度悬浮控制仿真研究

研究了一种新型的轴流式永磁偏置混合磁悬浮人工心脏结构。在该结构基础上,进行Maxwell磁力仿真与分析,得出了磁悬浮转子的状态数学模型;设计系统控制电路,列劳斯判据表,得到系统控制稳定时的PID参数范围;再通过MATLAB仿真,给出控制仿真结果。研究过程为磁悬浮人工心脏的稳定控制奠定了理论基础。

基于可变形部件模型的驾驶员人脸检测

交通监控中车辆驾驶室内环境较为复杂,如光线暗、遮挡、分辨率低等,现有的人脸检测方法效果不佳.提出了一种基于可变形部件模型的驾驶员人脸检测方法.通过提取聚合通道特征(局部二值模式和梯度方向直方图),得到候选人脸目标.基于监控图像中车牌与驾驶员人脸的相对位置存在比较固定的模式,将车牌与驾驶员人脸看作是可变形部件模型中的两个部件,用于验证车牌和候选目标相对位置关系的合理性,从而确定驾驶员人脸的位置.实验结果表明提出的方法提高了检测准确率和综合性能指标,有效地滤除了人脸虚警,且召回率影响较小.

基于改进的区域生长和Hough变换的钻孔图像水平裂隙识别

利用前视钻孔摄像系统(axial view borehole camera system,AVBCS)获取地质钻孔孔壁图像并分析地质结构是一种重要的地质勘查方式。针对目前钻孔孔壁图像基本由人工判读的现状,提出了一种基于改进的区域生长和Hough变换的钻孔孔壁图像水平裂隙识别算法。首先,利用三种图像预处理算法提高钻孔图像中裂隙区域的对比度;然后,结合OTSU算法和圆形度自动提取种子点,并利用双阈值准则进行中心区域生长,以消除中心干扰区域;最后,利用Hough变换算法完成裂隙的检测与识别。实验结果表明本文提出的裂隙识别算法对于不同的水平裂隙和离层图像都可以准确、自动地检测出裂隙。

新型Trans-Z源逆变器

针对Z源逆变器存在电容电压应力大、升压能力有限等缺陷,设计了一种基于Z源网络的新型Trans-Z源逆变器,分析了拓扑结构和工作原理,仿真和实验结果表明:与Z源逆变器相比,该逆变器具有升压能力强、电容电压应力小等优点。

Rejecting Outliers Based on Correspondence Manifold

发现在二幅图象之间的可靠的相应的点是在计算机视觉的一个基本问题，特别与 L 视觉框架的发展。这篇论文介绍歧管的通讯并且建议一个新奇计划由听说向上的看法拒绝孤立点歧管。建议计划独立于在出版工作要估计并且克服可得到的方法的下列限制的参量的模型：效率严厉地因孤立点百分比的增加和估计的模型参数的数字倒下；孤立点拒绝被结合模型选择和模型评价。真实图象对的实验显示出我们的建议计划的优秀性能。

An Analog Front End for Recording Neuronal Activity in Freely Behaving Small Animals

Extracting characteristic brain signals and simultaneous recording animals behaving could help us to understand the complex behavior of neuronal ensembles. Here, a system was established to record local field potentials (LFP) and extracellular signal or multiple-unit discharge and behavior synchronously by utilizing electrophysiology and integrated circuit technique. It comprised microelectrodes and micro-driver assembly, analog front end (AFE),while a computer (Pentium III ) was used as the platform for the graphic user interface, which was developed using the LabVIEW programming language. It was designed as a part of ongoing research to develop a portable wireless neural signal recording system. We believe that this information will be useful for the research of brain-computer interface.

A Miniaturized System for Neural Signal Acquiring and Processing

To collect neural activity data from awake, behaving freely animals, we develop miniaturized implantable recording system by the modem chip：Programmable System on Chip （PSoC） and through chronic electrodes in the cortex. With PSoC family member CY8C29466,the system completed operational and instrument amplifiers, filters, timers, AD convertors, and serial communication, etc. The signal processing was dealt with virtual instrument technology. All of these factors can significantly affect the price and development cycle of the project. The result showed that the system was able to record and analyze neural extrocellular discharge generated by neurons continuously for a week or more. This is very useful for the interdisciplinary research of neuroscience and information engineering technique. The circuits and architecture of the devices can be adapted for neurobiology and research with other small animals.

基于石墨烯超材料的可调谐电磁诱导透明

提出了一种基于石墨烯超材料的可调谐电磁诱导透明(EIT)结构,该结构是由长条-半圆环形状的石墨烯层和介质基底组成。通过频域有限差分法研究了该结构的特性,研究结果表明,由于石墨烯条和石墨烯半圆环之间发生相互作用,产生较弱的杂化,从而可以观察到EIT透明窗口。更重要的是,通过控制门电压,改变石墨烯的费米能级,可以在较宽的频率范围内实现透明窗口的动态调谐。通过调节石墨烯的费米能级,在透射峰附近群延迟接近0.4ps。同时还研究了石墨烯条和半圆环间的距离、圆环的半径、方位角等几何参数对EIT效应的影响,这些因素的改变对EIT效应产生了不同的影响。本文设计的超材料结构可应用于调制器和慢光器件等,对光开关、光存储等新型器件的设计有重要的指导意义。