基于计算机视觉的自动扶梯节能系统

自动扶梯是始终或阶段性保持运行状态的电梯,针对其在无人乘坐情况下持续运行所造成的能源浪费,提出了一种基于计算机视觉的自动扶梯节能控制系统,该系统由拍摄自动扶梯全景的摄像单元、微处理器和可编程逻辑控制器(PLC)构成;首先通过摄像单元获取整个自动扶梯的全景视频图像,接着利用混合高斯模型对全景视频图像进行背景建模处理,得到在自动扶梯上的前景对象;进而,根据自动扶梯上有无前景对象,生成相应控制信号,通过电梯PLC模块控制自动扶梯的运行和停止;实验结果表明,本文所开发的自动扶梯节能系统,对于自动扶梯上的对象物体,检测率在99%以上,可以较为可靠地控制自动扶梯运转与停止,达到预期的节能效果。     

A permanent magnetic perturbation testing sensor

A new PMP (permanent magnetic perturbation) testing sensor for NDT (nondestructive testing) was proposed for the first time based on the analysis of magnetic perturbation mechanism and PMP principle. Afterwards, the proposed PMP sensor was developed and its relevant structural parameter for design was analyzed by experiments. The comparisons among PMP, MFL (magnetic flux leakage) and ECT (eddy-current testing) sensor were carried out, which suggest that PMP is a new method. Finally, some practical engineering application cases of PMP sensor were presented, which further indicate that the proposed PMP sensor is of great practical value and the potential of wide industrial applications as a supplement of conventional NDT methods.     

考虑谐波因素的配电网无功补偿配置优化方法

针对谐波污染影响配电网无功补偿配置优化的特点,建立考虑谐波因素的配电网无功补偿配置优化简化模型。对各节点的电压有效值和电压总谐波畸变率进行约束,在保证目标函数最小的同时,将各节点的电压有效值和电压总谐波畸变率控制在允许范围之内。针对粒子群算法用于无功补偿优化时存在的局部最优收敛问题,作了算法改进,并将其应用于简化模型求解。选取了IEEE11节点配电网和实际配电网进行优化计算,结果验证了该算法改善电压水平、抑制谐波及降低配电网有功网损等作用的有效性。     

下坂地水电站1＃机组启动试运行综述

新疆下坂地水电站1 #机组启动试运行是对枢纽水工建筑、金属结构、机电设备的设汁、施工、制造、安装调试、检查、试验、验收等成果的综合考核.依据《水轮发电机组安装技术规范》( GB/T8564-2003)、《水轮发电机组启动试验规程》(DL/T507-2002)、设计和厂家有关图纸、技术文件、合同文件及其他应遵循的国家和行业规程规范,结合现场设备实际对下坂地1#机组启动试运行予以综述,其电气主接线如图1所示.     

基于行为的太阳帆群编队方法

文章提出了一种基于行为的太阳帆群编队路径规划方法。通过行为控制技术,在有限的感知信息条件下,便可获得自动的分布式控制律,将同质的各太阳帆导引至目标构型。导引过程中,各帆期望速度均为所设置三个行为速度(聚集、排斥、驻留)的矢量和,而各行为参数则利用目标构型的对称性进行设置。特别地,为了降低控制成本,聚集行为在仿真中利用了太阳引力、光压实际环境下形成的太阳帆轨道性质进行改造。通过日心悬浮轨道上的太阳帆群编队数值仿真,验证了文中方法的有效性和优越性。仿真结果表明,仅通过设置三个简单的行为,便可在日心悬浮轨道上得到许多有价值的太阳帆群构型。此外,通过修改其中的聚集行为,该方法可以很容易地移植到太阳帆行星悬浮轨道以及椭圆型三体问题中的太阳帆轨道编队应用上来。     

BaTiO_3 : Ce 桥式互泵浦相位共轭

在ＢａＴｉＯ３：Ｃｅ光折变晶体中实现了桥式互泵浦相位共轭．它和以往所有的互泵浦相位共轭镜不同之处在于这种晶体的ａ面入射光能产生强的自泵浦相位共轭,这使桥式互泵浦相位共轭产生的条件极为苛刻．然而本文通过选择最佳实验条件,使这种共轭光的的透射率高达４０％．也从理论上对ＢａＴｉＯ３：Ｃｅ桥式互泵浦相位共轭的形式作了分析和讨论．     

Nature-Inspired Interconnected Macro/Meso/Micro-Porous MXene Electrode

The geometric multiplication development of MXene has promoted it to become a star material in numerous applications including, but not limited to, energy storage. It is found that pore structure modulation engineering can improve the inherent properties of MXene, in turn significantly enhancing its electrochemical performance. However, most of the current works have focused on exploring the structure-effective relationships of the single-scale pore structure regulation of MXene. Inspired by Murray's law from nature where a highly graded structure of the organisms is discovered and used to achieve effective diffusion and maximize mass transfer, a hierarchically interconnected porous MXene electrode across micro-meso-macroporous is constructed. This MXene-based electrode provides large amounts of active sites while greatly shortening the ion diffusion channel. Finally, the zinc ion microcapacitor based on this MXene electrode exhibits an ultrahigh area-specific capacitance up to 410 mF cm⁻² and an energy density up to 103 µWh cm⁻² at a power density of 2100 µW cm⁻². The areal energy density outperforms the currently reported zinc ion microcapacitors. This study supports an effective strategy for electrode materials (including but not limited to MXene) to achieve ultra-short ion diffusion channels and maximum transport efficiency for next-generation high-performance energy storage.     

Personalized gesture interactions for cyber-physical smart-home environments

A gesture-based interaction system for smart homes is a part of a complex cyber-physical environment, for which researchers and developers need to address major challenges in providing personalized gesture interactions. However, current research efforts have not tackled the problem of personalized gesture recognition that often involves user identification. To address this problem, we propose in this work a new event-driven service-oriented framework called gesture services for cyber-physical environments (GS-CPE) that extends the architecture of our previous work gesture profile for web services (GPWS). To provide user identification functionality, GS-CPE introduces a two-phase cascading gesture password recognition algorithm for gesture-based user identification using a two-phase cascading classifier with the hidden Markov model and the Golden Section Search, which achieves an accuracy rate of 96.2% with a small training dataset. To support personalized gesture interaction, an enhanced version of the Dynamic Time Warping algorithm with multiple gestural input sources and dynamic template adaptation support is implemented. Our experimental results demonstrate the performance of the algorithm can achieve an average accuracy rate of 98.5% in practical scenarios. Comparison results reveal that GS-CPE has faster response time and higher accuracy rate than other gesture interaction systems designed for smart-home environments.     

Investigation of ultra‐wideband Bowtie antennas for phased array feed application

In this article, two new ultra‐wideband (UWB) dual‐polarized Bowtie antennas are investigated as the elements for a phased array feed for reflectors. In addition to its UWB impedance matching characteristic, the Bowtie antennas have stable large beam‐width and a low cross‐polar level over a wide frequency band with a compact size, which is an essence for phased array applications. The simulated and measured results state a low ohmic loss, good impedance matching (S₁₁ below ?15 dB) and good radiation performance, with a simple structure for easy manufacturing. The proposed antennas can be good candidates for phased array feed (PAF) in FAST and the SKA (square kilometer array) pathfinder PHAROS2 projects, and massive MIMO antennas in wireless communication systems.