基于红外图像处理的电气设备故障诊断方法

由于具有非接触、被动测量的优点,红外热像仪常被用于对电气设备进行故障监测与诊断。基于红外图像处理技术,对设备红外图像进行灰度转换,建立了红外图像灰度和温度之间的映射关系,通过灰度阈值可以对设备故障区域进行二值分割、故障区域的提取,实现了对设备故障区域识别和定位,并对故障程度作出判定。     

利用长波红外偏振成像与光强图像融合的实验研究

为解决红外迷彩对传统热成像系统的干扰问题,达到在战场上识别红外伪装目标的目的,进行了长波红外偏振成像与光强图像融合的实验研究。采集了典型战场背景的长波红外偏振图像,利用MATLAB编程对红外偏振图像处理得到了长波红外偏振度图像,进一步对偏振度图像和光强图像进行了融合。实验结果表明,红外偏振度图像比原始红外图像的灰度均值提高了53%,灰度标准差提高了90%,平均梯度提高了2.04倍;融合后的图像比红外偏振度图像的灰度均值提高了15%,灰度标准差提高了4%,平均梯度提高了17%。     

数字X光影像不均匀性的线性校正方法

针对数字X光成像仪(CR)中光纤排不均匀性引起的图像畸变,提出了一种线性校正方法.该方法采用典型的线性校正因子对图像畸变部分的灰度值进行校正,使原畸变图像在灰度值较小的地方,乘上一个大于1的校正因子;在灰度值较大的地方,乘上一个小于1的校正因子,校正因子的大小与该处灰度值偏离理想灰度值的大小成反比.实验结果表明,该方法能够使光纤排不均匀引起的图像畸变得到很好的校正.     

基于区域生长的红外图像火源检测方法

针对红外图像对比度低、分辨率差、背景干扰严重等问题,提出了一种基于区域生长的红外图像火源检测方法。利用阈值分割原理进行逐行扫描,所有灰度值大于阈值的像素被暂定为目标,所有灰度值小于阈值的像素被排除在外,然后,采用区域生长及类空间合并方法进一步确定火源区域。试验结果表明,该方法与归一化互相关匹配法(NCC)相比,误检率较低,精确度较高。     

大口径红外光学系统透过率测量装置

针对大口径红外光学系统的整机透过率测量难题,提出了基于图像灰度的单通道红外透过率测量方法,搭建了大口径红外光学系统整机透过率测量装置。首先,将黑体和靶标按照指定位置关系放置于待测红外光学系统的焦平面处,将红外热像仪放置于待测红外光学系统的入光口,采集被测系统的辐射图像;接着,将黑体放置于红外热像仪前,采集黑体辐射图像;最后,分别计算被测系统辐射图像均值和黑体辐射图像均值,二者比值即为被测系统的透过率。以某型大口径红外光学系统作为被测系统,开展了红外透过率测量实验。实验结果标明：本文方法测量值与设计值的绝对误差为0.85%,对测量结果不确定度进行分析,测量精度约为1.04%,测量方法可行。此方法测量过程简单,为大口径红外光学系统的整机性能评估提供了有效手段。     

基于均值漂移的红外舰船图像分割算法

提出了一种有效的舰船红外目标图像分割算法,利用均值漂移分割算法的二维灰度和灰度邻域信息,滤除了海面的强杂波干扰,同时又不会损失舰船目标信息。利用不同类别的灰度权重,将红外舰船图像分割成为天空、海水和舰船3类,从而将舰船从图像中有效地分割。由于采用区域节点和灰度直方图来表征图像,与原始图像像素节点表征图像相比,区域节点的个数远远小于原始图像像素节点,从而提高了算法计算效率。计算结果也表明,该算法能够在海面强杂波的干扰下,有效地提取红外舰船目标。     

基于梯度直方图变换增强红外图像的细节

针对红外图像信噪比低、目标边缘和细节模糊等缺点,提出了一种基于梯度直方图变换增强红外图像细节的方法。通过分析红外图像的梯度直方图,构造出一个高斯函数来扩展梯度直方图,增大图像的梯度值。采用直方图规定化法,实现图像的梯度直方图规定化,得到变换的梯度场。在从变换的梯度场重建增强的图像时,引入全变分(TV)模型来抑制噪声。实验结果表明,提出算法的图像信息熵比灰度直方图均衡化和规定化算法显著提高,明显增强了红外图像的纹理细节,为目标检测、跟踪和识别提供了高质量的图像信息。提出的算法采用有限差分法迭代进行求解和Visiual C++编程,对大小为480pixel×480pixel的图像的处理时间约为40ms,基本达到了工程应用对图像处理的要求。     

一种非均匀光照图像字符二值化小波分析法

图像二值化阈值的选取是灰度图像二值化处理中的关键，本文提出一种基于小波边缘检测的图像二值化方法。通过对图像进行二进小波变换，在最佳尺度上寻找出图像字符的边缘点，再根据边缘点处的灰度值来确定出二值化的阈值。应用于光照不均匀的多噪声车牌图像二值化，取得了良好的效果。     

结合统计分布和非下采样Contourlet变换的红外小目标检测

在分析存在背景和噪声干扰下的红外小目标检测方法的基础上,提出了一种时空结合的红外小目标检测算法.首先,基于相邻帧背景图像灰度值变化的特点,提出了基于三阶中心矩统计分布确定小目标区域方法,接着对图像进行非下采样Contourlet变换(NSCT),定义子带的能量系数,并结合各个子带的能量系数得到各点的能量值,进而得到一个...     

基于灰度图像纹理分析的电主轴不平衡故障诊断方法

针对转子不平衡,首次提出了基于灰度图像纹理分析的故障诊断方法。首先将转子振动信号转化为二维灰度图像,并利用局部二值模式提取灰度图像的纹理特征;通过二维傅里叶变换提取灰度图像的特征频率,并采用灰度图像二维矩阵的平方和来表征图像的明暗程度,由此来区分不同程度的不平衡故障。在某电主轴系统平台上,完成了转子正常和3种不同程度转子不平衡的故障诊断试验,结果表明所提出的方法能够有效区分不同程度的转子不平衡,为旋转机械的故障诊断提供了一种新方法。     

一种经济实用的智能红外遥控模块

介绍了红外遥控发射和接收的原理 ,提出了一种基于单片机红外遥控解码的方案。该方案思路新颖、原理简单、无需外围芯片、经济可靠、通用灵活 ,可方便地应用于各种红外遥控场合 ,组成通用的操作模块     

2.4GHz无线局域网技术及其山区应用工程

无线局域网是计算机网络的重要组成部分.本文基于在一个山区县建成无线局域网的实践,研究无线局域网传输技术当中的直接序列扩频、无线局域网系统的组成和各种应用,并介绍无线局域网的标准.无线局域网由于不需要连线、数据传输速率高,可移动性、可靠性和抗干扰性能好,成为有线网络的补充和延伸,有很好的发展前景.     

Design and analysis of an infrared range sensor system for floor-state estimation

Most blind and vision-impaired people use a white cane or a guide dog to aid their walking. The conventional white cane helps the user to perceive the environment simply by identifying the presence of nearby obstacles. In the present study, three infrared range sensors were used to identify the floor state. The sensor system, affixed to the user’s belt, does not require swinging motion or any other movement by the user. The three sensors are configured radially, and the design parameters are selected based on the sensor characteristics. The main difference from the conventional range sensor system for the blind is that the infrared range sensor system identifies three discrete states (even surface, ascending stair, descending stair). The condition for the state transition was derived from a sensor system model. Additionally, the effects of sensor system movement were verified by covariance analysis.     

Design and analysis of flow measurement of conductive liquid and transmission via optical channel

Measurement and transmission of flow rate of a conducting liquid through a pipe line is generally done by using electromagnetic flow meter which consists of a large electromagnet and a pair of sensing electrodes along with electronic system and involves large cost and size. In the present paper, a very simple flow sensing system for a conducting liquid is proposed and this system does not require any electromagnet and involves very low cost. Moreover in modern instrumentation system the signal transmission through optical communication system is being more preferred where the transmitted signal does not suffer from measurement error due to electromagnetic interference. So an MZI based optical communication technique has been described in the present paper. The proposed technique consists of only four insulated conducting electrodes in contact with the flowing liquid along with an electro-optic system for signal conditioning and transmission of the measured signal to a remote location. The performance of the sensor and the transmission system has been analyzed in the form of a bridge network with bridge arms represented by lumped parameter polarization impedances among the electrodes. The theoretical equations explaining the operation of the bridge network with a stabilized sinusoidal ac source and MZI based electro-optic system have been derived. A proto type unit has been designed, fabricated and its function has been studied experimentally and the experimental results are reported in the paper. A very good linear characteristic under streamline condition of the proposed unit has been observed with very good repeatability and very small uncertainty of measurement. The graphical abstract is shown below.     

井下电池电量检测器串口转换模块设计

现有矿井下计算机不具备电池电量检测功能,为此设计了一种USB/RS232接口模块。从矿井下采集到的电池电量数据可以通过此模块传输到上位机的USB总线上,从而使上位机得到电池电量的采样值。测试结果表明该USB/RS232接口转换模块能通过其原有的虚拟串口与上位机的USB总线接口实现双向数据传输,且该系统的设计指标符合矿井工作的要求。     

基于光纤通道的红外视频数据采集系统

为了把红外视频数据从光电跟踪设备旋转的机上摄影系统传输并存入到机下数据采集系统中,设计了一套红外视频数据光纤传输、存储系统。视频信号电平转换后由FPGA打包组帧,经过物理层芯片协议转换,电/光转换后进行光纤传输,数据经过光纤旋转连接器进入机下数据采集系统。该系统集成了光电转化、物理层解码、数据的恢复,然后经过PCI总线与本地计算机进行DMA传输,把数据存入SATA硬盘中。取代了传统视频采集卡,集数据传输、存储为一体,简化了系统结构。     

傅里叶变换近红外分析仪在烟叶质量分析监测中的应用研究

近红外技术在烟草品质分析应用中得到了广泛的应用,由于应用厂方提供的分析软件,在某些情况下不能满足用户的要求。根据热电(Thermo)公司近红外分析仪提供的OPC接口,编写客户端应用软件,满足了烟叶质量分析的准确性和传送过程中的安全性要求。     

Data fusion for PT100 temperature sensing system heating control model

This research examines temperature monitoring and automated heating system control. The temperature sensing module utilizes a wireless ZigBee chip. A terminal interface to the RS232 transmission infrared transmitter module issues a control packet through the infrared transmitter module to the infrared receiver module to control the electromagnetic oven. ZigBee chip wireless transmission is the essential network topology design. The subsequent maintenance advantage uses the terminal interface is a Visual Basic program to design the system monitoring interface. Concrete results are: (1) adaptive weighted fusion algorithm for data fusion computing. (2) Completion of the PT100 temperature sensing modules. (3) ZigBee wireless transmission. (4) The infrared receiver, launch control module developed. (5) The design of the interface in this system covers monitoring, automatic control, manual control functions.     

基于非正交频分复用的智能电管家数据传输系统设计

提出一种基于非正交频分复用的智能电管家数据传输系统设计。通过 PCIE 内部结构的程序控制数据流的方向,来划分系统的读操作预计写操作研究。根据预处理操作降低数据传输偏差;利用非正交频分复用技术的子载波调制信号,来提升频率利用率和降低系统数据传输偏差。通过设备采集,得到数据类型选择其对应的大体数据传输方式;利用椭圆曲线密码学与高级加密标准抵御智能电管家数据篡改攻击,运用加密反向操作和认证签名解密密文维护数据安全,从而实现智能电管家数据安全传输。仿真结果表明,所建系统数据传输时效性强、吞吐量高且丢包率低,具备极强的实用性,深入优化了智能电管家系统的推广及应用。     

Sensitivity analysis of systems with a cascade compensator embedded in a Smith predictor to dead-time variation

This paper considers the use of a cascade compensator embedded in a Smith predictor in the forward path of a system being designed, which is an effective way to solve two problems: providing the desired process performance in the system and placing the dead-time element outside the closed loop so that it only increases the transient time by the value of the time delay and does not affect the overshoot value. It is shown that the Smith predictor should be used with caution because, being based on an additive signal compensation scheme, it may be not robust and may require accurate knowledge of the time-delay value for robust implementation. The problem of sensitivity analysis of the system to dead-time variation is stated and solved.