Synergistic effect of siloxane modified aluminum nanopowders and carbon fiber on electrothermal efficiency of polymeric shape memory nanocomposite

The present study reports an effective approach of significantly enhancing electrothermal efficiency and shape recovery performance of shape memory polymer (SMP) nanocomposite, of which shape recovery was induced by electrically resistive heating. Metallic aluminum (Al) nanopowders synthesized from Al³⁺ solution were chemically grafted onto carbon fiber. Siloxane groups were grafted onto surfaces of the Al nanopowders to enhance the interfacial bonding between the carbon fiber and SMP matrix via van der Waals force and covalent bond, respectively. The siloxane modified Al surfaces could improve both the electrically induced shape recovery performance and electrothermal efficiency through facilitating the electrically resistive heating from carbon fiber into the SMP matrix. Effectiveness of the synergistic effect between siloxane modified Al surface and carbon fiber was demonstrated to achieve the electrical actuation for SMP nanocomposites at a low electrical voltage below 4.0 V.     

基于Arduino Web Server的红外家电控制系统

本文利用Arduino Web Server技术针对传统家电如何低成本地升级为智能家电,设计了一种通过网页界面控制红外家电的控制系统。该系统主要由Arduino Mega2560开发板、Arduino Ethernet Shield模块、万能红外模块、以及继电器模块组成,实现了通过网页界面对红外家电控制和对开关电器的电源通断控制。该系统设计简单可靠且硬件成本较低,易于实现。通过实验验证了预期的功能。     

全球智能电视姿势识别专利分析

综合运用TDA、Innography等多种分析工具,对德温特增值专利数据库中的用于智能电视的全球姿势识别专利进行总体趋势及创新技术人才等分析,主要包括专利技术总体发展趋势、全球专利市场布局、专利技术国家分布、热点技术领域、前沿技术、创新团队、重要专利等,以期帮助企业了解智能电视姿势识别技术的发展趋势和主要竞争对手情况,为智能电视姿势识别技术合作研究和产业发展提供借鉴。     

基于Python脚本的智能家居业务测试脚本设计及实现

本文根据智能家居系统的特点和要求,介绍了我们研发的自动化测试平台。在此平台基础上,提出了基于Python脚本层次化的架构设计方法,并通过搭建智能家居中具体的门磁开关业务,进行了测试用例分析,验证了智能家居业务的功能和可靠性测试。通过Python语法编写而成的测试方法,具有良好的描述能力,并且产生的测试方法易于维护,该方法对于开展智能家居业务测试具有重要意义。     

Why do people access news with mobile devices? Exploring the role of suitability perception and motives on mobile news use

Using self-reported survey data (N = 281), the present study explores the structural relationships among mobile users’ perceptions of the suitability of two types of mobile news (political feature news and entertainment news), users’ motivations for mobile news usage, and their behavioral patterns. Our findings show that two types of perceived suitability for mobile news, particularly for political feature news, are strongly associated with all dimensions of motivations for mobile news usage. Furthermore, as predicted, our findings show that the information-seeking motive is the very factor that determines mobile news usage. The results also reveal that the accessibility motive mediates the relationship between the perceived suitability of obtaining news via a mobile device and users’ mobile news behavior. However, contrary to our expectation, the social utility motive does not mediate the relationship between users’ perceptions of the suitability of mobile devices for this purpose and their mobile news usage. Finally, the information-seeking and accessibility motives each have an indirect effect on the association between perceived suitability and mobile news usage. The implications of the study and recommendations for future research are also discussed.     

Smart control of a horizontal axis wind turbine using dielectric barrier discharge plasma actuators

Rotating stall around a small-scale horizontal axis wind turbine was experimentally studied to characterize and assess smart rotor control by plasma actuators. Phase-locked Particle Image Velocimetry was used to map the flow over the rotor blade suction surface at numerous radial stations at a range of tip-speed-ratios. Flow separation occurred from the inboard of the blade and spread radially outwards as the tip-speed-ratio reduced. Plasma actuators placed along the span that produced a chord-wise body force had very little effect on the flow separation, even when operated in pulsed forcing mode. In contrast, plasma actuators along the blade chord that produced a body force into the radial directions (plasma vortex generators) successfully mitigated rotating stall. Torque due to aerodynamic drag was reduced by up to 22% at the lowest tip-speed-ratio of 3.7, suppressing stall over the outboard 50% of the blade. This was due to quasi-two-dimensional flow reattachment in the outboard region, and shifting of a fully stalled zone towards the hub in the inboard region because the plasma-induced body force counteracted the Coriolis-induced radial flow. This can significantly increase the turbine power output in unfavourable wind conditions and during start-up.     

Is the self-read water meter a pro-poor innovation? Evidence from a low-income settlement in Nairobi

This study investigates the Jisomee Mita, an innovation based on ICT-powered metering at property level aimed at increasing access to piped water and sewerage in low-income areas in Nairobi, Kenya. We present empirical findings from field investigations and actor interviews, which are analysed using a novel framework drawing on studies of business models, sustainability transition, and the history of technology. We explore the critical interface between utility infrastructure and potential customers as a locus of innovation. We find that the property owners are the main benefactors of self-read meters, while low-income end-users still depend on over-priced and unsafe water. The Jisomee Mita thus cannot be called a pro-poor innovation in its current implementation and context.     

Design,fabrication and properties of 1–3 piezoelectric ceramic composites with varied piezoelectric phase distribution

Here the 1–3 connectivity cement/polymer based piezoelectric composites with varied piezoelectric phase distribution were designed. The dielectric, piezoelectric and electromechanical properties of the composites were studied. The results indicate that the composite with varied distribution of piezoelectric ceramic has large relative permittivity, piezoelectric strain constant and electromechanical coupling coefficient at the thickness vibration mode. The composites with varied distribution of matrix phase have larger piezoelectric voltage constant, smaller mechanical quality factor and acoustic impedance value than those with varied distribution of piezoelectric ceramic phase. The electromechanical coupling property of the composites at the planar vibration mode shows obvious dependence on matrix phase distribution. The novel piezoelectric composites show potential applications in fabricating ultrasonic transducers with specific surface vibration amplitude.     

基于可视化技术的电网智能调度系统设计应用

智能调度系统作为建设坚强智能电网的核心内容备受关注。在分析了智能调度系统及可视化技术相关概念和研究现状的基础上,提出了智能调度可视化系统的设计总体思路与原则。通过对智能调度可视化系统的主要功能介绍及软硬件的构建分析,以及实际电力调度实时运行可视化系统的应用介绍,对所建系统进行具体说明,可为构建省级电网智能调度系统提供参考。     

基于Echelon公司电力载波通信技术的路灯单灯控制解决方案

基于美国Echelon公司的电力载波通信技术,可以构建一个实现单个路灯控制功能的路灯解决方案,该解决方案已经应用在欧洲的很多城市。系统的实施,使得城市路灯管理部门降低了路灯系统的运营成本,提高了路灯系统的服务效率。这种路灯系统可以节省50%的能源支出,节约30%的维护成本支出,是实现绿色、节能城市的重要手段。