Humidity‐Resistive Triboelectric Nanogenerator Fabricated Using Metal Organic Framework Composite

With its light weight, low cost, and high efficiency, the triboelectric nanogenerator (TENG) is considered a sustainable and renewable energy source for self‐powered or mobile electronics. However, the performance of TENG is seriously affected by humid environment. Here, for the first time, TENG with improved performance under high humidity is obtained by adding HKUST‐1 (Cu₃(BTC)₂, (BTC = 1,3,5‐benzenetricarboxylate or trimesate)) to polydimethylsiloxane (PDMS) matrix. At 10% relative humidity (RH), an effective power (3.17 mW) of the composite TENG based on 5 wt% HKUST‐1 is obtained at a load resistance of 10 MΩ, which is 13 times higher than that of the TENG based on pure PDMS. More importantly, the performance of composite TENG remains constant or becomes higher even under high humidity, while that of conventional TENG dramatically decreases at the same condition. The excellent humidity‐resistive performance comes from the remarkably enhanced electron‐trapping capacity and dielectric constant due to the absorption of HKUST‐1 to water molecules. This work not only demonstrates that a metal organic framework is an effective filler to improve the performance of TENG but also provides a novel strategy to obtain high output properties under highly humid environments by increasing the electron‐trapping capacity and dielectric constant.     

Empirical Analysis on Influence Mechanism of Cohesiveness and Collective Efficacy of Virtual Community Based on Triadic Reciprocal Determinism

The virtual community has become a new life style as for human, but the public＇s acceptance is relatively low at present. So the research about the mechanism of the influence on the cohesiveness and the collective efficiency in virtual community has an important theoretical value and practical value. In the paper, the key variables that affect virtual community cohesiveness are extracted from two aspects--self-perception of community members and community environment, and the influence mechanism model of virtual community cohesiveness and community collective efficiency is established based on Triadic Reciprocal Determinism. By means of the questionnaire on the community members and the empirical analysis, the key factors influencing cohesiveness of virtual community are brought up, as well as the mechanism that the four dimensions of cohesiveness work on collective efficiency. According to the results, it is practically meaningful that the problems and insufficiency in the operation of existing virtual community are discovered, which guides the operating managers of the virtual community to formulate operation policy of the virtual community for operating managers to develop strategies.     

OBS网络信道分级竞争解决方法研究

通过分析光突发交换网络突发数据包产生竞争的原因和现有的几种解决机制,提出了信道分级竞争解决方法,并对其性能进行仿真研究,得出了不同信道配置下突发数据包丢包率和平均处理时延曲线.结果表明,该方法可以有效的降低数据包丢失率,支持不同的业务需求,是一种实用的方案.     

基于VHS-ADC的电力电子实验平台的设计

为满足电力电子相关课程教学和研究的要求,本文设计了一套以VHS—ADC实时仿真系统为核心的电力电子实验平台,利用VHS—ADC平台自带的模型库,可将Matlab／Simulink中建立的复杂的控制算法,应用于所设计的实验装置中,实现在线运行的实时仿真试验。基于该平台设计了单相无源逆变电路实验,并进行了仿真。仿真结果表明...     

隐形斗篷的研究

基于坐标变换理论设计了菱形、不规则四边形和扇形隐形斗篷。利用COMSOL Mul-tiphysics对其进行仿真得到,覆盖斗篷后电磁场可以"拐弯"绕着物体走,斗篷内部区域未受到电磁场干扰,隐形效果均得到了较好的证实。这三种形状的隐形斗篷比圆柱形和球形斗篷更为常见,因而在减少物体的雷达散射截面(RCS)方面具有更为广泛的实用性。     

非均匀磁光光栅干涉结构的磁场灵敏性

根据分段均匀模型分析了非均匀磁光光纤光栅(MFBG)与相应非磁性光栅的等效性,从而可直接利用OptiSystem仿真软件研究非均匀MFBG的光谱特性.在此基础上,深入研究了基于非均匀MFBG的Michelson干涉结构,分析了相位补偿法用于磁场测量的工作原理.仿真结果表明,线性啁啾MFBG的磁场灵敏性高于均匀和切趾MF...     

大型汽车覆盖件拉深模具的激光表面强化处理

本文介绍了使用激光表面强化技术对大型模具进行处理的工艺过程和达到的技术性能指标,并通过生产应用实例,介绍了模具激光表面强化处理的使用效果,证明该技术是解决大型模具表面硬化难题的有效途径。     

基于预测滤波的航天器GPS定位实时性处理方法

对于航天器高动态定位，针对接收机处理耗时带来的非实时性现象，利用Kalman最优预测方法进行处理。首先建立了系统状态方程和量测方程，且在满足精度条件下对系统模型进行简化。仿真结果表明，该方法能有效减小高动态环境下定位非实时性带来的误差。     

MUDS在"村村通"中的应用方案探讨

介绍MUDS在农村有线电视发展过程中所起的作用,重点阐明MUDS系统的特点及其5大组成部分:数字电视中心、上行站、数字MUDS发射基站、数字MUDS直放站、用户接收系统。     

基于边缘权重分析的水面弱目标红外增强

为了提高水面环境下的弱目标红外图像的视觉质量,本文基于红外辐射理论,结合边缘分析与透射率等参数获取,实现了复原增强。通过辐射理论分析获得了原始场景图像关于透射率与路径辐射光的函数表达。利用暗通道先验,获取粗糙的透过率,结合边缘权重分析与导向滤波,获取精细透过率。在边缘分析基础上,确定了路径辐射。观测实验证明本文增强结果的潜在目标区域的局部对比好,突出了边缘与纹理特征。测试结果表明,本文方法运行速度快,增强的视觉效果好,客观评价值高,为后期的目标探测、识别等应用奠定了基础。