光源光强对颜色对比度的影响研究

彩色图像成像时,光源的亮度变化影响着光源的光谱相对功率分布,影响着照明光源的色温,与成像后的检测目标对比度密切相关。因此研究在光源光谱不变的条件下,光源的亮度变化对颜色对比度的影响。光源的亮度调节采用PWM脉冲编码调节,分析了色块对比度随着光源的亮度变化规律,在CIEL*a*b*空间利用色差来评定色块间的对比度,根据最大色差选择了一个最佳的光源照度等级。     

基于法契纳效应的高速公路限速方法研究

长时间高速驾驶容易造成驾驶员视觉和神经的双重疲劳和速度适应性提高,使得驾驶员对速度信息的获取和处理速度下降,造成驾驶员出现无意识超速行为。为此,文中将法契纳效应成色规律、人眼的辨色机理和高速情况下的视觉特性、道路的实际环境结合,设计一种施画在高速公路护栏上的矩形图案。在行车速度达到限制值时,驾驶员即可发现两旁的护栏出现彩色,从而在行车过程中实时意识到当前超速行驶状态。     

简易车辆类型识别系统设计

从实时视频数据流中检测出运动车辆并对其进行车辆类型识别是智能交通系统的重要组成部分。本文提出一种从AVI视频文件中检测出运动车辆并识别其车辆类型的方案,其系统处理过程分为车辆图像获取、图像处理和车辆外观特征数据提取三个主要部分。经实验验证,该设计简单可行。     

Improving assimilation of SeaWiFS data by the application of bias correction with a local SEIK filter

Ocean-biogeochemical models show typically significant errors in the representation of chlorophyll concentrations. The model state can be improved by the assimilation of satellite chlorophyll data with algorithms based on the Kalman filter. However, these algorithms do usually not account for the possibility that the model prediction contains systematic errors in the form of model bias. Accounting explicitly for model biases can improve the assimilation performance. To study the effect of bias estimation on the estimation of surface chlorophyll concentrations, chlorophyll data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) are assimilated on a daily basis into the NASA Ocean Biogeochemical Model (NOBM). The assimilation is performed by the ensemble-based SEIK filter combined with an online bias correction scheme. The SEIK filter is simplified here by the use of a static error covariance matrix. The performance of the filter algorithm is assessed by comparison with independent in situ data over the 7-year period 1998–2004. The bias correction results in significant improvements of the surface chlorophyll concentrations compared to the assimilation without bias estimation. With bias estimation, the daily surface chlorophyll estimates from the assimilation show about 3.3% lower error than SeaWiFS data. In contrast, the error in the global surface chlorophyll estimate without bias estimation is 10.9% larger than the error of SeaWiFS data.     

Underwater sonar image recognition based on gray-spatial histograms

A new gray-spatial histogram is proposed, which incorporates spatial information with gray compositions without sacrificing the robustness of traditional gray histograms. The purpose is to consider the representation role of gray compositions and spatial information simultaneously. Each entry in the gray-spatial histogram is the gray frequency and corresponding position information of images. In the experiments of sonar image recognition, the results show that the gray-spatial histogram is effective in practical use.     

彩色多普勒评价正常胎儿心功能的研究

用彩色多普勒技术对50例正常胎儿心脏收缩及舒张功能的各种参数全面、系统地观测分析，评价正常胎儿心脏收缩和舒张功能。结果表明：胎儿时期，胎儿肺循环处于高阻力状态，肺动脉平均压高于主动脉，肺循环阻力高于体循环阻力；胎儿心室舒张顺应性低下，心房的收缩对胎儿心脏维持正常功能有着重要的作用；胎儿时期心脏不仅存在着结构上的右心优势而且存在着功能上的右心优势。     

基于色彩心理与工效的船舶舱室色彩搭配原则

不同的舱室色彩会使船员产生不同心理反应,合理的色彩搭配有利于船员身心健康和作业能力的保持。根据色彩心理和工效原理,总结与分析国内外研究成果,探讨船舶舱室色彩搭配的基本原则。     

彩色防滑减速带在公路控速上的应用研究

指出了常用减速带存在的缺陷,引入了彩色防滑减速带这一新型防滑减速交通安全设施,并详细介绍了其施工方法,对彩色防滑减速带的规范化施工有很大的指导意义。     

C3I系统中基于颜色特征的战场图像快速检索

针对C^3I系统中战场目标图像的检索问题，给出一种基于颜色特征内容的检索方法。对于战场图像采用FISI颜色模型，计算H分量的颜色直方图，通过直方图匹配，计算直方图的相似距离，进而检索出相似图像。通过一个简单的基于颜色特征的战场图像检索原型表明上述方法切实有效。     

分层CS-LBP和HOG特征融合的人脸识别研究

针对单独的纹理特征只能提取图像的纹理信息而不能得到图像轮廓边缘信息的问题,在人脸识别的特征提取研究中提出了分层CS-LBP和分层HOG特征的融合方法.对图像分别进行多次CS-LBP和HOG特征的提取,得到分层CS-LBP特征提取图像和分层HOG特征提取图像,对分层的特征提取图像再次提取分层CS-LBP和分层HOG特征,并将两种分层特征进行融合,得到更有效的人脸的纹理及边缘轮廓特征.在ORL和GT人脸库上的实验结果验证了所提出的分层特征融合方法的有效性.