Multi-scale fusion residual encoder-decoder approach for low illumination image enhancement

The sensing light source of the line scan camera cannot be fully exposed in a low light environment due to the extremely small number of photons and high noise, which leads to a reduction in image quality. A multi-scale fusion residual encoder-decoder (FRED) was proposed to solve the problem. By directly learning the end-to-end mapping between light and dark images, FRED can enhance the image's brightness with the details and colors of the original image fully restored. A residual block (RB) was added to the network structure to increase feature diversity and speed up network training. Moreover, the addition of a dense context feature aggregation module (DCFAM) made up for the deficiency of spatial information in the deep network by aggregating the context's global multi-scale features. The experimental results show that the FRED is superior to most other algorithms in visual effect and quantitative evaluation of peak signa-to-noise ratio (PSNR) and structural similarity index measure (SSIM). For the factor that FRED can restore the brightness of images while representing the edge and color of the image effectively, a satisfactory visual quality is obtained under the enhancement of low-light.     

Irregular Time‐Varying Stress Degradation Path Modeling: a Case Study on Lithium‐ion Cell Degradation

The aim of this paper is to investigate the issue of degradation modeling and reliability assessment for products under irregular time‐varying stresses. Conventional degradation models have been extensively used in the relevant literature to characterize degradation processes under deterministic stresses. However, the time‐varying stress, which may affect degradation processes, widely exists in field conditions. This paper extends the general degradation‐path model by considering the effects of time‐varying stresses. The new degradation‐path model captures influences of varying stresses on performance characteristics. A nonlinear least square method is used to estimate the unknown parameters of the proposed model. A bootstrap algorithm is adopted for computing the confidence intervals of the mean time to failure and percentiles of the failure‐time distribution. Finally, a case study of lithium‐ion cells is presented to validate the proposed method. Copyright © 2015 John Wiley & Sons, Ltd.     

预应力混凝土超静定结构的变刚度分析法

变刚度分析法是一种解预应力超静定结构问题的便易行且精度较高的分析方法,该分析方法的计算结果与屡系列大型试验所验证。     

相位一致性和KDDA结合的人耳识别方法

随着人耳识别技术的发展,如何寻找不受光照和对比度影响的特征并用于识别成为研究热点之一。本文提出一种利用相位一致性对人耳进行特征提取的方法,该方法首先从8个方向计算人耳图像中每点的相位一致性,然后对经过相位一致性变换的输出图像分块求和,形成特征矢量,最后通过KDDA将特征向量投影到低维高可分空间,并用欧式距离对人耳图像分类。对77个人,共308幅人耳图像进行实验,在等误率为1.7%的情况下,识别率可以达到98.2%左右,验证了该方法所提取的人耳特征不受光照影响。     

Improving content visibility for high‐ambient‐illumination viewable display and energy‐saving display

Abstract— Nowadays, low‐contrast viewing of LC displays (LCDs) occurs very often, which includes the viewing of mobile LCDs at high ambient illumination and the viewing of LCDs at low‐power mode. These cases result in low‐content visibility and low contrast, leading to an unpleasant viewing experience. In this paper, a technique to improve the perceived contrast and visibility of images at low‐contrast viewing conditions is proposed. The proposed approach enhances image brightness with content and ambient adaptive image brightening and highlights visual parts and boundaries with non‐photorealistic rendering. The proposed technique enables longer battery life for mobile LC devices and makes mobile LC devices viewable at high ambient illumination. It also enables TVs with extreme low‐power consumption and smart‐grid responsive TVs.     

Master‐slave synchronization for delayed Lur'e systems using time‐delay feedback control

This paper deals with the problem of designing delayed feedback controllers of master‐slave synchronization for Lur'e systems with time‐variant delay (0≤τ₀≤τ(t)≤τ_m). Through partitioning the intervals [0, τ₀] and [τ₀, τ_m], respectively, and choosing two augmented Lyapunov‐Krasovskii functionals(LKFs), two delay‐dependent synchronization criteria are formulated in the form of linear matrix inequalities (LMIs), in which the conservatism can be greatly reduced by thinning the partitioning of delay intervals and employing convex combination. Thus the sufficient conditions can be derived for the existence of delayed feedback controllers, and the controller gain matrices can be achieved by solving the established LMIs. Finally, three numerical examples are given to illustrate the presented synchronization schemes. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

Global exponential synchronization of stochastic switching networks with time‐varying delay

This paper is concerned with the global exponential synchronization of stochastic delayed switching networks via hybrid control. The network under investigation is quite general to reflect the reality, where the network topology consists of r modes and switches from one mode to another according to a Markovian chain with known transition probability. Parameter uncertainties, time varying delay and stochastic disturbances are all taken into account in this study. Based on the Lyapunov functional method and stochastic analysis techniques, some new criteria for the global robust synchronization via hybrid control are established. Finally, one example with numerical simulation is given for illustration. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

符号M阵列面结构光多分辨解码方法研究

研究了符号M阵列面结构光图像的多分辨解码方法,结合基于形心特征的标准符号的分类和识别,着重提出了多分辨解码过程中未识别区域的提取方法,并结合实际问题提出了图像标记和符号识别的特殊处理方法,如分割符号间隔、填充十字型区域等,进而实现照度不均面结构光图像解码率最大化的目的.同时该解码方法也大大提高了照度不均模式图像解码的执行效率.     

基于改进的Mean-shift驾驶员人脸跟踪算法研究

为了实现对驾驶员人脸实时跟踪,提出了一种改进的Mean-shift算法。首先对人脸提取类Haar特征,使用类Haar特征构造弱分类器,然后根据样本的权值分布构造出强分类器,形成人脸检测分类器;由于光照变化等因素的影响,引入红外主动照明模式,通过隔离可见光照,基本上消除了光照变化对人脸检测造成的影响;针对Mean-shift算法在被跟踪目标发生快速移动时容易跟踪失败的缺点,改进了Mean-shift算法：当目标发生快速移动时,采用SSD（Sum of Square Dif-ference）算法进行全局搜索。以实际驾驶员人脸检测与跟踪实验为例进行了大量实验,提出的方法比Mean-shift算法的速度快、准确度高。     

Static output feedback sliding mode control for time‐varying delay systems with time‐delayed nonlinear disturbances

In this paper, a robust stabilization problem for a class of linear time‐varying delay systems with disturbances is studied using sliding mode techniques. Both matched and mismatched disturbances, involving time‐varying delay, are considered. The disturbances are nonlinear and have nonlinear bounds which are employed for the control design. A sliding surface is designed and the stability of the corresponding sliding motion is analysed based on the Razumikhin Theorem. Then a static output feedback sliding mode control with time delay is synthesized to drive the system to the sliding surface in finite time. Conservatism is reduced by using features of sliding mode control and systems structure. Simulation results show the effectiveness of the proposed approach. Copyright © 2009 John Wiley & Sons, Ltd.