基于小波变换的传感器故障检测技术研究

介绍了小波变换的基本理论及小波技术用于传感器故障检测的基本原理，给出了传感器故障检测方法，仿真实例证明了这一技术的有效性。     

RBF神经网络在传感器故障诊断中的应用研究

提出一种基于RBF神经网络的传感器在线故障诊断方法,用某气囊隔振系统隔振装置中大量的传感器数据进行了仿真实验,验证了方法的可行性.通过对每个传感器建立单独的神经网络预测模型,实现多传感器的故障诊断.     

起重机销轴式测力传感器的设计和应用

介绍了粘贴应变片和激光焊接应变片两种销轴式测力传感器,以及它们各自的优缺点。指出起重机销轴式测力传感器选用激光焊接薄膜应变片,能够收到高精度、高稳定性、好重复性的良好效果。     

滑坡监测无线传感器网络基于事件的信道分配方案

在高速铁路沿线的山体斜坡上部署无线传感器网络,用于监测山体斜坡变化情况。综合考虑传感器节点能量有限性和对采集信息的实时性需求,提出一个基于事件的信道分配方案用于滑坡监测信息的传输。以是否有列车经过山体斜坡区域作为事件,当无列车经过时,为节点分配活跃周期和睡眠周期,采用TDMA的方式唤醒节点并分配一个可用信道进行数据传输,从而在保证数据传输的前提下节省节点能量,延长网络寿命;当有列车即将经过时,节点完全进入活跃周期,采用多个信道并行传输的方式传输数据,减少传输过程中由于信息碰撞造成的信息丢失和重传,从而降低传输时延,提高信息传输的实时性。最后,通过仿真实验分析系统性能,证明所提方案的有效性。     

Evaluation of detection sensitivity and count performance of advanced vehicle detection technologies at a signalized intersection

This article evaluates the stop-bar detection and count performance of three advanced vehicle detection sensors under various environmental conditions at a signalized intersection. Continuing advancements to vehicle detection technologies and improvements to their detection capabilities to overcome issues from impacting conditions necessitates testing the performance of new and upgraded sensor products to evaluate their performance and identify the most suitable products for various climates and weather conditions. The three evaluated sensors were Autoscope Encore video, Iteris Vantage Edge 2 video, and Wavetronix SmartSensor Matrix microwave sensors. The three sensors performed with high detection sensitivity during ideal environmental conditions with up to 99.9% detection accuracy levels and are suitable for traffic monitoring centers that rely on remote access to the monitored sites and the collected data. However, they were affected by some extreme adverse weather conditions, mainly daytime and nighttime snow, daytime fog, dawn lighting, and strong winds (for high mounted devices). The selection of a sensor product will depend on the type of application and the priority given to the type of traffic data being collected. Overall, the Iteris video sensor performed with the highest detection sensitivity levels, with the Wavetronix Matrix microwave sensor performing similarly under most conditions (14 of 19 evaluated conditions). Autoscope video provided the highest count accuracies and also provides a much broader data collection capability. The results of this study will help transportation agencies in selecting suitable vehicle detection sensor technologies for future installations within their jurisdiction and improved data collection.     

Fast direction of arrival algorithm based on vector-sensor arrays using wideband sources

An acoustic vector sensor （AVS） can capture more information than a conventional acoustic pressure sensor （APS）. As a result, more output channels are required when multiple AVS are formed into arrays, making processing the data stream computationally intense. This paper proposes a new algorithm based on the propagator method for wideband coherent sources that eliminates eigen-decomposition in order to reduce the computational burden. Data from simulations and lake trials showed that the new algorithm is valid： it resolves coherent sources, breaks left/right ambiguity, and allows inter element spacing to exceed a half-wavelength.     

深基坑排水系统介绍

本文根据现场条件及雨量分析,介绍深基坑排水系统的布置。     

虚拟仪器技术在传感器实验台中的应用

虚拟仪器技术是微电子、通信、计算机等现代科学技术高速发展的产物.通过对虚拟仪器技术的深入研究,把该技术应用到传感器实验台的硬件驱动、数据采集、结果分析、数据显示、数据输出等,改变了传统的设计方法,实现用计算机技术结合虚拟仪器来实现传感器试验台的功能,使传感器实验台的结构简单合理、灵活方便、一机多用.     

考虑降雨影响的深基坑边坡稳定性分析

以大源渡航电枢纽二线船闸基坑工程为例,结合饱和-非饱和理论,通过有限元软件Geo-Studio中seep/w模块和slope/w模块建立二维数值模型,对强降雨情况下边坡渗流状态进行分析,得到边坡内部含水率和孔隙水压力变化规律以及安全系数和滑裂面的变化情况。结果表明:随着降雨历时的增加,坡面含水率逐渐增加,雨水不断向更深层土体入渗,地下水位线不断上升,基质吸力逐渐消散,坡体表面形成暂态饱和区,安全系数随之减小。降雨停止后,水分逐渐流出坡体,含水量逐渐减小,地下水位随之逐渐下降,正孔压减小,基质吸力逐渐恢复,安全系数逐渐增大。降雨入渗对边坡浅层土体影响较大,对深层土体影响较小,一般形成浅层破坏。     

基于比例系数-有效独立法对圆柱壳声辐射预报的测点优化布置研究

文章以圆柱壳结构为研究对象,以反映测点模态振型相关性的比例系数来修正传统的有效独立法,提出了一种基于比例系数-有效独立法的测点优化布置算法。并分别用基于模态和响应的评价准则与现有的三种测点布置方法进行比较。结果表明:比例系数-有效独立法可有效地避免测点间的信息冗余问题,在保留结构振动特性方面具有明显的优势;并且能更加准确地预报圆柱壳结构的声振响应,是一种适合圆柱壳结构较为理想的测点优化布置算法。