嵌入式软件GUI自动化测试平台研究

为实现嵌入式软件的GUI自动化测试,本文对嵌入式软件GUI自动化测试现状深入分析,提出了一种无侵入式的GUI自动化测试框架,利用图像采集与信息识别技术实现测试用例结果判断;利用键盘鼠标模拟技术模拟测试用例执行的人机交互;利用脚本语言嵌入技术实现用例编辑与转换、利用嵌入式软件GUI测试自动化控制技术实现用例的自动驱动与执行。在此基础上,设计并研发了嵌入式软件GUI自动化测试平台,能够方便、有效的实现无侵入式的嵌入式GUI自动化测试。     

Entanglement transfer from two-mode squeezed vacuum light to spatially separated mechanical oscillators via dissipative optomechanical coupling

In this paper, we propose a scheme to generate an entangled state between two spatially separated movable mirrors by injecting the two-mode squeezed optical reservoir to the dissipative optomechanics, in which the movable mirrors can modulate the linewidth of the cavity modes. When the coupling between the mirrors and the corresponding cavity modes is weak, the two driven cavity fields can respectively behave as the squeezed-vacuum reservoir for the two movable mirrors by utilizing the effect of completely destructive interference of quantum noise. Thus the mechanical modes are prepared in a two-mode squeezed vacuum state. Moreover,when the coupling between the two mirrors and the cavities modes is strong, the entanglement between the two movable mirrors decreases because photonic excitation can preclude the completely destructive interference of quantum noise, but the movable mirrors are still entangled.     

嵌入Ag纳米颗粒层的DNA忆阻器

构建了具有“Al/DNA-CTMAB/Ag NPs/DNA-CTMAB/ITO”结构的有机忆阻器件, 并对其电流-电压 (I-V)曲线进行测量. 结果表明, 嵌入Ag纳米颗粒层, 不仅可以增强器件的导电性, 而且忆阻特性也显著提高. 当颗粒粒径在15–20 nm范围时, 开-关电流比I_ON/I_OFF能够达到10³. 器件的I-V特性受扫描电压幅值V_A的影响, 随着V_A的增大, 高阻态的电流变化较小, 而低阻态的电流明显增大, 开(或关)电压V_SET (V_RESET)和I_ON/I_OFF增加. 实验还发现, 器件高低阻状态的相互转换取决于外加电场的方向, 说明该忆阻器具有极性.     

基于液晶空间光调制器的太赫兹波频谱调制

频谱可调制的太赫兹波具有广泛的应用价值。利用一台纯相位式的液晶空间光调制器对飞秒激光脉冲进行空间整形,通过改变飞秒激光脉冲的横向空间分布,实现太赫兹波频谱的调制。在实验中,利用光泵浦整流方式产生太赫兹波,并利用太赫兹时域光谱系统对太赫兹信号进行探测。通过GS算法在液晶空间光调制器上加载不同的相位图,获得了不同的飞秒激光脉冲横向空间分布。通过改变探测距离和飞秒脉冲的空间分布参数,实现了太赫兹波频谱的调制。还利用菲涅尔衍射算法对这一过程进行了理论模拟,理论模拟结果与实验结果吻合的较好,这充分说明了基于飞秒脉冲空间整形的太赫兹光谱调制技术的可行性。     

弹簧参与的微小振动一定是简谐运动吗

振动和波动是生活中的一种非常普遍而重要的运动形式,其中简谐振动是最简单、最基本的运动,弹簧振子是研究简谐运动的最基本模型.在研究弹簧参与的微小振动时,部分学生不能很好的判定弹簧参与的微小振动是否为简谐运动.本文讨论了系统作简谐运动的充要条件,并通过4个具体例子详细分析了弹簧参与的微小振动.     

槽道尺寸对平板式环路热管性能的影响

设计开发了一套平板式环路热管,比较了2 mm×1.5 mm和1 mm×1 mm(高×宽)两种蒸气槽道环路热管在不同倾角和充液率下的性能。结果发现,两种蒸气槽道在相同条件下最低启动功率相同,但前者启动时间和过渡时间较后者短。稳定运行时,除充液率为55%且功率小于150 W外,其他情况下前者运行温度比后者低。变工况运行时,随功率的增大,温度后者变化很大,而前者变化较小,前者自适应能力强。对于传热特性,两种槽道环路热管的热阻都随功率的增大而逐渐减小,最后趋于平稳;对水平、充液率为55%的系统,功率较小时前者热阻较大,功率增大后,其值大幅减小,215W时仅为0.12℃/W。     

基于动态雷达比的气溶胶消光系数及光学厚度反演

激光雷达以其高垂直空间分辨率和高时间分辨率的优势在大气气溶胶监测中具有重要作用。在利用Fernald法反演气溶胶消光系数和光学厚度的过程中,雷达比是反演结果的主要误差源。在目前的应用中雷达比普遍都是取固定值,这就必然给雷达反演带来误差。通过对污染物以及气象数据与雷达比的逐步回归分析,建立了雷达比估算模型,从而实现雷达比的动态估算。研究表明:雷达比的变化与空气中PM2.5质量浓度、相对湿度、SO2和NO2质量浓度等具有明显相关性。相比于固定值,利用动态雷达比反演的气溶胶消光系数和光学厚度精度明显提高。     

Microtextures Induced by Nanosecond Laser on Ni–Co Alloy Coatings

Ni–Co alloys have a wide range of applications in various fields owning to their excellent physical, chemical, and mechanical properties. In this paper, we prepare Ni–Co alloy coatings on 316L stain steel surfaces by electroplating. We present a novel approach utilizing a nanosecond laser to induce microtextures on Ni–Co alloy coatings. We study experimentally the effects of laser power and scanning rate on the surface morphologies of Ni–Co alloy coatings. The results indicate that the shape and size of induced microtextures can be controlled by the laser power and scanning rate. The size of grains increases with increase in the work current of the laser (WCL) at a certain scanning rate. With the WCL constant, the size of grains decreases with increase in scanning rate while their average height increases. It is a simple and easily-controlled method for the fabrication of microstructures on Ni–Co alloy coatings, which has promising applications in investigations of the properties of microtextured surfaces, such as friction, adhesion, and wetting.     

Can 2‐acylpyrroles form an intramolecular hydrogen bond?

The formation of intramolecular hydrogen bonding by certain N‐substituted 2‐acylpyrroles has been demonstrated by B3LYP/aug‐cc‐pVDZ calculations, the quantum theory of atoms in molecules, and the natural bond orbital method. Total electron energy densities H_BCP at the bond critical point of the H?O bond were applied to analyze the strength of these interactions. The relations between quantum theory of atoms in molecules, carbonyl stretching vibrational modes ν_{C = O}, and natural bond orbital parameters associated with the formation of the C–H?O interaction have been established. The short contacts were found experimentally in the crystal structure of a new 2‐acylpyrrole derivative 5‐chloro‐2‐oxopentyl‐1‐(5‐chloro‐2‐oxopentyl)pyrrolo‐2‐carboxylate. The influence of 2‐ and N‐substitution of 2‐acylpyrroles on C‐H?O interaction energy is discussed. It was found that the methylene group may act as a proton donor leading to a red‐shift or blue‐shift phenomenon of the ν_C–H stretching mode. Copyright © 2015 John Wiley & Sons, Ltd.