火焰温度测量技术研究

综述了火焰的分类及其温度测量方法,介绍了热电偶法、成象法、激光光谱法、辐射法和声波法的测量原理,并分析比较了它们的适用性和各自特点。简要描述了用于固体火箭发动机羽焰温度测量的多点多波长高温计。最后,展望了火焰温度测量的发展趋势。     

BP神经网络的火焰图像温度检测方法

基于炉膛火焰温度不同，与之相对应通过CCD摄取的炉膛火焰图像颜色也不同，提出了一种检测炉膛火焰温度的方法。将获取的炉膛火焰图像RGB模型转换为HSI颜色值，用H、S值作为BP神经网络输入，通过样本图像训练后，拟合H、S与温度T的非线性关系，计算得到炉膛火焰温度值。实验表明，计算温度与实际温度良好相符，温度测量方法切实可行。     

火焰燃烧区域空气声速与温度关系的实验研究

为使声学方法能对火焰温度进行精确测量,实验研究了火焰燃烧区域中空气声速与温度的关系。首先对非火焰气体环境中的声速与温度进行测量,然后在此基础上对不同燃料燃烧的火焰区域进行声速测量实验,并结合热电偶测得火焰温度,进而得到火焰中空气声速与温度的关系。结果表明:在固定距离下,与室温空气环境相比,高温烟气环境会使声波的传播时间减小,火焰环境会使声波的传播时间变长;在非火焰区域,空气声速与温度的关系符合理想气体中声速与温度的关系;在火焰燃烧区域,空气声速与温度关系偏离理想气体的声速与温度方程,与按照理想气体计算的声速结果相比,实际声速测量值偏小;对于同种燃料的火焰,随着火焰温度升高会出现空气中的声速减小的现象。     

早期火灾火焰图像特征提取分析

分析早期火灾火焰主要特征,对早期火焰图像进行处理后,提取火焰图像的尖角和圆形度图像数据并进行统计,从结果可以看出,本文算法可以识别和区分火焰和其它干扰源。     

电站锅炉炉膛温度分布测量仪的研制

本阐述了在恶劣的工业生产环境对温场分布监测时采用成象光谱法的理由；创造性地将成象光谱、数字图像处理方法和面阵ＣＣＤ成象技术有机地结合在一起，通过合理的装置设计，研制出全炉膛火焰温度场分布监测装置；在对黑体的标定中得到预期结果，并在现场测量中满意的结果。     

基于智能手机APP的火焰温度分布检测研究

提出了一种利用辐射理论与可见光图像处理技术,基于Android系统APP测量火焰温度的方法。利用手机自带相机采集火焰的可见光图像,通过提取可见光图像各个像素点的RGB,标定镜头确定辐射亮度与RGB的定量关系,利用维恩辐射定律计算出各个像素点的温度值,实现随时随地测量火焰温度。开发的APP测量火焰温度的技术可以通过拍照或图库选择的方式输入燃烧图像,提取照片的曝光时间、白平衡、ISO等重要参数,经过计算,即可生成燃烧二维温度分布图。实验测量了反扩散火焰的温度分布,结果表明：与多波长测量方法相比,智能手机测量温度最大值的相对偏差为4%。     

燃烧剂火焰温度精确测试的新方法

本文分析了燃烧剂火焰温度测试的诸多难点，提出用光电比色计测试火焰温度的方法，并解决了火焰辐射系数ε不易确定问题。     

领域统计火焰检测算法及其实验研究

针对目前火焰检测器中采用的火焰燃烧判别算法存在的不足,提出了一种新的邻域统计火焰检测算法。首先根据选定的火焰图像区得到火焰图像的特征灰度级,然后通过统计特征灰度级邻域范围内的像素数对火焰状况进行判断,得出了正确的检测结果。该方法可以在线修改参数,为正常燃烧状态、不稳定燃烧状态、低负荷状态和灭火状态设定不同的判别阈值,保证了在不同工况下准确地检测出火焰燃烧状况,提高了检测的可靠性。     

炉膛火焰检测原理和锅炉燃烧器管理系统维护探讨

根据美国ＦＯＲＮＥＹ公司的燃烧器管理系统在国内的应用，介绍火焰检测的原理，并从系统的设计、安装及运行工况等方面详细分析和探讨锅炉燃烧管理系统的维护，以保证机组的安全、稳定的运行。     

TDLAS火焰燃烧温度测量方法改进

基于可调谐二极管激光吸收光谱技术(TDLAS)双线温度测量原理,设计了7153.748-7154.354 cm~(-1)谱线对单激光器TDLAS燃烧温度测量系统,对平面预混火焰燃烧温度进行测量,发现由于吸收较弱、信噪比较低等造成测量结果与热电偶测量结果相对偏差较大。针对这一问题,提出了采用(7185.597-(7444.352+7444.371))cm~(-1)双激光器TDLAS系统,并结合增加光程方法来改进原有的温度测量精度。结果表明:采用双激光器可放宽谱线对的选择范围,选择吸收更强的谱线对可以有效提高信噪比,并且结合增加光程,可实现TDLAS温度测量结果与热电偶测量偏差由10%降低到5%。     

Color image denoising using evolutionary computation

Noise suppression in multichannel data sets, such as color images, has drawn much attention in the last few years. An issue of paramount importance in designing color image filters is the determination of the coefficients that should be used to weight the inputs to the filter. In this study, we propose an evolutionary computation‐based approach to select and optimize the coefficients in the class of weighted vector directional filters. Using a genetic algorithm, we were able to adapt the filter weights to match varying image and noise characteristics. Extended experimentation with realistic image processing applications, including television image enhancement and virtual restoration of artworks, indicates that the proposed filters are capable of removing noise while preserving chromaticity information, edges, and fine details, as well as structural image content. © 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 15, 236–251, 2005     

Single image dehazing using multiple transmission layer fusion

Methods for single image dehazing have been widely studied based on the atmospheric scattering model and dark channel prior (DCP); they usually adopt an additional refinement procedure such as guide filtering to restrain the halo artefacts, but it easily induces undesirable textures in the final transmission map, and further leads to an overall contrast reduction and detail blur. In this paper, an efficient approach was proposed to enhance single hazy images without any refined post-process, which is based on the strategy of multiple transmission layers fusion. In order to estimate the final transmission map adapting to different scenes reasonably, the multiple transmission layers were derived based on DCP with different kinds of adaptive local watch windows. To make sure the atmospheric light is estimated in the most haze-opaque region, the corresponding region was searched hierarchically with the quadtree subdivision method in the top part of the minimal channel of the input image. Finally, the hazy image was restored through solving the scattering model. Comparison experiments verify that the proposed method is straightforward and efficient, which can reduce the halo artefacts significantly, yielding satisfactory contrast and colour for varied hazy images.     

环境试验设备温湿度校准系统的研制

介绍基于MSC1200的温湿度自动校准系统。以JJF 1101-2003《环境试验设备温度、湿度校准规范》为设计依据,硬件以美国TI公司的MSC1200作为测量、信号处理以及通信核心部件,组成一套多通道高精度温湿度采集仪。按照校准规范的要求设计专用的校准软件,通过RS232接口与温湿度采集仪通信,将测量数据进行显示、绘图、存储,计算并自动生成满足要求的原始记录及校准报告,从而实现校准过程程序化、规范化、自动化,满足计量部门对环境试验设备温湿度校准的需要。     

cDNA microarray image segmentation using root signals

A vector processing based framework suitable for cDNA microarray image segmentation is introduced and analyzed in this paper. By using nonlinear, generalized selection vector filters the framework proposed here classifies the cDNA image data as either microarray spots or image background. The solution converges to a root signal that represents the segmented cDNA microarray image with the regular spots ideally separated from the background and with their coloration uniquely described by dominant color vectors. It will be demonstrated that the framework readily unifies image denoising, enhancement, data normalization, irregular spot rejection, and spot segmentation in one processing step delivering excellent performance at reasonable computational cost. © 2006 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 16, 51–64, 2006     

机载摄像设备图像稳定方法探讨

通过对现有几种运动估计算法性能进行比较,结合机载红外摄像系统获取动态图像序列的特点,提出了有效地用于机载摄像系统电子稳像的运动估计算法。它具有精度高和速度快等特点,用该算法对实拍的航摄图像序列进行稳像试验,运动矢量的估计时间仅为10ms。实验证明了该算法用于航摄动态图像序列稳定的有效性。     

Automated image mosaicking

Abstract

This paper developed and implemented automated image mosaicking procedures to produce seamless and smooth mosaics from random sequences of digital aerial images and satellite images. The procedure employs automated algorithms for global image registration, seam line extraction, radiometric adjustment, and composition of overlap images. Results of the experimentation on mosaicking black and white orthorectified aerial images and on mosaicking multi‐resolution color infrared SPOT‐2 and Landsat‐5 satellite images show that the implementation of automated conjugate point extraction and image matching algorithms automates the establishment of geometric registration among overlapped images, while the seam line selection and two‐step lookup table histogram matching approaches facilitate creating globally smooth and qualitative mosaics. The system developed in this paper makes complex composition of multi‐source multi‐resolution multi‐band images with different geometric and radiometric characteristics an easy and efficient solution for producing reliable mosaic images.     

Application of digital image analysis to strain measurement at elevated temperature

Digital imaging techniques are applied to the measurement of surface displacement and strain at elevated temperatures. A simple surface preparation using high temperature paint together with a CCD video camera for digital imaging serve as the basis for the measurements. Mathemetical correlation of the surface intensity pattern between reference and deformed states is used to measure local surface deformation. The method is non-contacting and full field. Displacement and strain measurements have been made at temperatures to 600°. Coefficients of thermal expansion of three metals have been measured using this technique and compared to strain gauge and handbook values. Limitations and potential extensions of the method are discussed.     

Digital image processing of crack growth using a modified caustic set-up

A digital image processing method to analyze the fringes of a modified caustic is described. The experiment is easy to perform and simple, and the image processing technique and detecting system can operate automatically, precisely, and quickly. Recording with two video cameras two sets of caustic images during crack growth, the computers process data with a specified fringe counting algorithm. We obtained two complete sets of data, one providing a full field view of the distribution of stress and the other providing the stress intensity factor.     

双目系统中图像随机噪声的分析

图像立体匹配的精度是保证双目系统测量准确性的重要因素，也是系统研制过程中需要解决的难点问题。对影响双目系统中图像立体匹配精度的随机噪声建立了一种局部统计量符合高斯分布的简化统计模型，基于这个噪声模型设计了滤波方案。实验表明，滤波后图像立体体匹配的精度优于1／4像素。