结合HSV与纹理特征的视频阴影消除算法

目的 在视频监控目标检测应用中,场景中的阴影会直接影响目标检测的准确度,因此阴影抑制算法研究显得尤为重要。目前广泛使用的是HSV（hue,saturation,value）阴影抑制方法,但是该方法存在由于亮度比值的阈值不稳定而造成将运动目标也检测为阴影的问题。针对该问题,本文提出了一种结合HSV与纹理特征的视频阴影消除方法。方法 首先将输入的图像使用传统的混合高斯模型建立背景并在灰度空间中提取前景,其次在HSV空间使用亮度比的阈值方法检测阴影,二者综合得到运动目标;针对由于亮度比值的阈值不稳定而导致的前景误检为阴影的问题,采用了LBP（local binary pattern）算子结合大津阈值（OTSU）提取部分运动目标。最后将LBP算子结合大津阈值提取的部分运动目标与HSV空间检测的目标两者相或,最终去除运动目标的阴影。结果 本文选用在CVPR-ATON和CAVIAR标准视频库中多个场景的阴影视频,将本文算法与SNP算法、SP算法、DNM1算法和DNM2算法进行对比仿真,实验结果表明本文算法在阴影检测率和阴影识别率的平均值上提升约10%。结论 本文提出的视频阴影消除算法结合了HSV与纹理特征,可以在不同的环境中有效地去除阴影,运动目标保留完整,可适用于智能视频监控、遥感图像和人机交互中。     

Dynamic output feedback control of saturated switched delay systems under the PDT switching

This paper is devoted to saturated control of switched delay systems. The main focus is to find a suitable switching law and saturated output feedback controllers such that the closed‐loop systems are asymptotically stable and have the disturbance tolerance/rejection capacity. A mixed slow/arbitrary switching approach, so‐called persistent dwell time (PDT) switching, is used to design the switching law. Compared with the slow switching, it is more general and leads to more flexibility in the process of constructing switching signals. More importantly, the proposed PDT is dependent on state delay, which includes the previous delay‐independent PDT. Next, time‐varying ellipsoids and a prescribe l₂‐gain are introduced to characterize the disturbance tolerance and rejection capacities of systems, respectively. Based on the proposed results, the relation between delay‐dependent PDT and level of disturbance tolerance/rejection is shown. Finally, saturated controllers working in time‐varying hull controllable regions are designed. Thus, the considered problem is solved. An example is exploited to illustrate the effectiveness of the proposed results. Copyright © 2016 John Wiley & Sons, Ltd.     

A parametric periodic Lyapunov equation with application in semi-global stabilization of discrete-time periodic systems subject to actuator saturation

This paper is concerned with semi-global stabilization of discrete-time linear periodic systems subject to actuator saturation. Provided that the open loop characteristic multipliers are within the closed unit circle, a low gain feedback design approach is proposed to solve the problem by state feedback. Our approach is based on the solution to a parametric discrete-time periodic Lyapunov equation. The proposed approaches not only generalize the corresponding results for time-invariant systems to periodic systems, but also reveal some important intrinsic properties of this class of periodic matrix equations. A numerical example is worked out to illustrate the effectiveness of the proposed approaches.     

一种新型的科学健身训练仪的设计

随着科技技术的发展,人们的体力劳动越来越多的被现代化技术装置所取代,造成劳动者得了很多现代文明病。人们意识到健身运动的重要性。但不是任何形式、任何强度的运动都能达到健身的目的。针对这一问题设计了一种科学健身训练仪,通过监测人的心率和血氧饱和度,通过心率和血氧同运动强度的关系指导人们进行最佳健身训练,对过度运动预警,同时还具备了对运动效果评估的功能。系统电路具有小型化,模块化,低功耗的特点,较适合家庭健身训练时使用。     

Analysis and design of output feedback control systems with actuator saturation

A dynamic output feedback controller design approach based on cone complementary linearisation procedure is proposed for linear time-invariant （LTI） systems with actuator saturation. First, the estimation of the domain of attraction is given. Then, a design method to find a larger estimation of the domain of attraction is presented. In the process of design, nonconvex conditions are obtained, so a cone complementary linearisation procedure is exploited to solve the nonconvex feasibility problem. Two examples are given to illustrate the efficiency of the design method.     

输出饱和线性系统的稳定性及L2增益性能

考虑输出饱和线性系统的稳定性以及L     

Efficient and robust shot change detection

In this article, we deal with the problem of shot change detection which is of primary importance when trying to segment and abstract video sequences. Contrary to recent experiments, our aim is to elaborate a robust but very efficient (real-time even with uncompressed data) method to deal with the remaining problems related to shot change detection: illumination changes, context and data independency, and parameter settings. To do so, we have considered some adaptive threshold and derivative measures in a hue-saturation colour space. We illustrate our robust and efficient method by some experiments on news and football broadcast video sequences.

Improvement of luminance and luminous efficacy in PDPs

Abstract— The dependence of PDP luminance and efficacy on the input power was investigated for several Xe‐Ne gas mixtures. The input power was varied in two ways: namely, by changing the dielectric‐layer capacitance (thickness) and by changing the sustain voltage. A distinctly different behavior was found; for increasing capacitance the efficacy decreases markedly, whereas for increasing sustain voltage the efficacy increases. A design window comprising the combination of a high Xe concentration and a high sustain voltage was suggested. In this window, a high luminance and a high efficacy are concurrent. A 4‐in. test panel with 10% Xe in Ne has been realized showing a white luminance of 2040 cd/m² and an efficacy of 2.3 lm/W for continuous sustaining at 50 kHz with a sustain voltage of 225 V.     

Selenium Speciation Studies from Soan-Sakesar Valley,Salt Range,Pakistan

Abstract

A regional study of Selenium (Se) speciation in surface waters, groundwaters, and saturation extracts from Soan-Sakesar valley Salt-Range, Pakistan was started in March 1994 and completed in October 1996. Groundwaters, streams, and springs had median concentrations of: total Se 48, 404.5, and 82 μg/l; Se^+VI 40, 350 and 51 μg/l; Se^+IV 8, 48 and 29 μg/l; Se^-II 0, 6.5 and 2.0 μg/l, respectively. The concentration of Se exceeded the recommended water quality guidelines for drinking and irrigation water of 10 and 20 μg/l, respectively. In saturation extracts, median total Se, Se^+VI, Se^+IV and Se^-II were 190, 146, 37 and 7.0 μg/l, respectively. Uchhali, Khabbaki and Jahlar lake water samples had the mean concentration of: total Se 2103, 670 and 297 μg/l; Se^+VI 1777, 470, and 233 μg/l; Se^+IV 291, 166 and 39 μg/l; Se^-II 35, 34 and 25 μg/l, respectively. The Sakesar limestone Formation of Eocene age rich in shales and fossils (median Se concentration 7.2 μg/kg) are considered to be the source of selenium that have enriched soils of Soan-Sakesar valley. Selenim speciation results show the abundance of selenate in all the environmental samples. A linear relationship between Se^+VI and pH (R²= 0.84, 0.58, 0.88, 0.82, and 0.91; significant at the 0.05 level) for groundwater, saturation extract, stream, spring, and lake waters were noted, suggesting that the Se^+VI in the samples is highly associated with pH. Linear relationships were established between Se^+VI and Mg, NO₃, and SO₄ for groundwater (R²= 0.24, 0.16, and 0.64; significant at the 0.01 level) and surface water (R²= 0.96, 0.14, and 0.91; significant at the 0.001 level). This suggests the high concentrations of Mg, NO₃ and SO₄, which strongly adsorb and compete with selenium for surface site, increases the Se^+VI fraction. The results show that the higher percentage of selenate on other species in the analyzed samples is favored by higher pH and oxidizing environments of the valley.     

碳酸盐岩气藏岩电参数试验研究

为了提高储层参数的精度,针对某区块碳酸盐岩岩心开展试验研究,根据试验分析结果提供更为准确的测井资料解释模型.讨论在不同含水饱和度及围压条件下岩心电阻率的变化规律,并探讨围压对岩心电阻率的影响机理.