A study of optimal viewing distance in a parallax barrier 3D display

The optimal viewing distance was proposed as a parameter for designing a parallax barrier 3D display. It can be designed based on simple geometric method and by considering the pitches of image display pixels and parallax barrier, or even including the aperture ratios of the image display pixels and parallax barrier. It can be analyzed by using ray tracing method. By considering the optical refraction index of the cover glass, the angular behavior of the system becomes more realistic; however, the geometric method is difficult to be used. We propose a revised method for estimating the view distance and angular behavior. In this paper, we have demonstrated a designated eye position (DEP) for each view and shown that multiple DEPs make a circular curve around the center of the display. We prove the new concept by comparing the optical ray tracing calculations and optical measurement.     

基于状态反馈的功率放大器线性化方法

笛卡尔座标反馈线性化技术是减小RF功率放大器非线性失真的一种有效方式,但在高频输入下信号传输延时使系统类似于一高阶系统,严重影响反馈系统的稳定性,一般只适用于窄带系统。为提高系统性能,提出了一种新的状态反馈的线性化技术,并通过二次优化实现参数的优化配置并进行仿真。仿真结果表明通过新方法设计的Cartesian回路增强了系统的稳定性,提高了反馈线性化技术的线性化带宽,而且设计的系统对延时的变化具有较强的鲁棒性。     

Analysis of Two-Dimensional Non-Rigid Shapes

Analysis of deformable two-dimensional shapes is an important problem, encountered in numerous pattern recognition, computer vision and computer graphics applications. In this paper, we address three major problems in the analysis of non-rigid shapes: similarity, partial similarity, and correspondence. We present an axiomatic construction of similarity criteria for deformation-invariant shape comparison, based on intrinsic geometric properties of the shapes, and show that such criteria are related to the Gromov-Hausdorff distance. Next, we extend the problem of similarity computation to shapes which have similar parts but are dissimilar when considered as a whole, and present a construction of set-valued distances, based on the notion of Pareto optimality. Finally, we show that the correspondence between non-rigid shapes can be obtained as a byproduct of the non-rigid similarity problem. As a numerical framework, we use the generalized multidimensional scaling (GMDS) method, which is the numerical core of the three problems addressed in this paper.     

图像插值算法在对数极坐标变换中的应用

传统对数极坐标变换算法对图像具有平滑作用,易造成图像细节信息丢失。该文提出将一种基于小波变换的插值算法用于图像对数极坐标映射。该算法对图像作小波变换得到4个子图,并对各子图作对数极坐标变换,其中最优对应像素的确定根据不同子图的特点采用相应的插值算法,对子图映射图作逆小波变换。实验表明该算法是有效的。     

运用特征点匹配的柱面全景图像快速拼接算法

针对大幅面图像的拼接问题,提出了一种新的基于特征点的柱面全景图像快速拼接算法。该算法在Harris角检测算法提取特征点的基础之上,针对传统RANSAC（random sampling consensus）算法在提纯匹配点时计算极其复杂,难以实现快速拼接的问题,设计了专门的聚类预筛选的方法进行图像特征点的预匹配,显著提高了特征点匹配的效率;在图像融合部分提出了最佳路径与HSI颜色空间的亮度权重函数相结合的算法,既有效消除了拼接图像中的鬼影现象,又使拼接图像达到了平滑融合效果。实验结果表明,该算法具有匹配精度高、鲁棒性强、计算效率高的特点。     

双振动电机同步最优控制方法

应用最优控制理论,提出新的双振动电机的相位同步控制策略。双振动电机在振动机械,如振动筛、振动打桩机及振动成型机等,有着广泛的应用。现代的双振动电机以相位控制同步方式工作,而目前采用的主要是主从跟踪式PID控制同步方法。这种方法虽然实现简单,但控制效果较差。基于最优跟踪控制技术,在状态空间中对双振动电机系统的振动频率和相位差同时进行控制,取得了较满意的实验结果。该控制技术可以很方便地被推广到对3台以上的振动电机进行多机相位同步控制中。     

基于照片的人体尺寸信息自动提取技术

针对3D扫描仪成本高,传统手工软尺测量效率低的状况,在保证精度的前提下,尝试应用图像处理理论从满足一定条件的照片提取人体尺寸信息,为建立人体尺寸信息库提供一种信息采集的自动化方法.通过对实验结果的分析,本文验证了此方法的可行性,并提出未来的研究方向.     

嵌入式SRAM的优化修复方法及应用

为了提高SRAM的成品率并降低其功耗,提出一种优化的SRAM.通过增加的冗余逻辑及电熔丝盒来代替SRAM中的错误单元,以提高其成品率;通过引入电源开启或关闭状态及隔离逻辑降低其功耗.利用二项分布计算最佳冗余逻辑,引入成品率边界因子判定冗余逻辑的经济性.将优化的SRAM64K×32应用到SoC中,并对SRAM64K×32 的测试方法进行了讨论.该SoC经90nm CMOS工艺成功流片, 芯片面积为5.6mm×5.6mm, 功耗为1997mW.测试结果表明:优化的SRAM64K×32 在每个晶圆上的成品率提高了9.267%,功耗降低了17.301%.     

Formulation to obtain the most reliable aggregate mix with quantity and other constraints

The aggregate batch mixing problem determines the proportion (or relative masses) in which aggregate batches with different gradations are to be blended so as to achieve a target mix with a given gradation. As shown in previous studies, the gradation of a batch is not homogeneous and should be considered stochastic. Also, when batches are blended in the field there are random variations in the masses or proportions of individual batches in the mix. Assuming batch gradation and blend masses as stochastic implies that the notion of a mix (blend) satisfying the gradation of a target mix becomes stochastic. In such a framework, every mix has a reliability with which it satisfies the definition of the target mix. In addition, a mix is also required to satisfy various restrictions. This article presents an optimization formulation to determine the most reliable mix while satisfying restrictions on available quantity, budget, etc.