应用环境光传感器的颜色恒常性算法

现有的颜色恒常性算法在常规场景中通常能获得准确、稳定的光源颜色估计结果,但在内容单一、具有大面积单一颜色表面的低颜色复杂度场景中仍有较大概率出现超容限的估测误差。利用设置于摄影镜头旁的环境光传感器,提出一种应用环境光传感器的颜色恒常性算法。首先建立传感器置信度评估模型,然后针对不同置信度设计基于颜色空间转换与基于传感器辅助中性色像素提取的两种光源颜色估计方法。此外,还建立包含传感器测量结果的数据集。测试结果表明,相比现有具有最高精度的同类算法,所提算法的角度误差均值、中位数、最差25%均值分别下降32%、21%、41%。所提算法应用于常规场景和低颜色复杂度场景时均具有优势。     

用神经网络校正微型颜色传感器颜色特性的方法研究

采用光学积分原理设计的光电色度仪器,由于其结构简单、测量速度快、成本低等优点已被广泛地应用在产品的色度检验控制过程中。基于微型颜色传感器的颜色测量仪器也属于光电色度类仪器,由于它不能完全模拟标准色度观察者和标准光源,即不能完全满足卢瑟(Luther)条件,所以其测量值RGB与三刺激值XYZ并不相等,且存在非线性关系。讨论了采用BP神经网络进行微型颜色传感器颜色特性校正的方法,其优点是对仪器的匹配滤色片要求较低,只要在测量软件中增加训练好的校正网络程序,就可以获得准确的颜色三刺激值。     

反射式表面粗糙度光纤传感器及其模糊算法

本文提出了一种新型表面粗糙度光纤传感器,阐述了它的结构、工作原理,给出了测试结果.运用模糊算法,分析实测数据,得到系统的测量规则和隶属函数.经过模糊推理和决策计算出相应的输出值.该算法可减小测量误差,提高测量精度,扩大测量范围.本系统能准确地识别R_a分别为0.012μm,0.025μm,0.5μm,0.1μm的被测表面.     

用模糊算子法对用通俗语言描述的颜色标志的定量评价

本文在确定颜色模糊性的基础上,用模糊算子的方法分析了用通俗语言描述的颜色标志,提出了一种颜色标志的定量方法。     

无线传感网络节点隶属度模糊定位算法研究

无线传感网络RSSI算法定位精度很高,但易受环境干扰。本文针对其不足,提出基于节点隶属度模糊算法,并应用于RSSI定位模型之中。新算法首先利用岭形分布对RSSI初始信号模糊化取得隶属函数,再根据隶属度近似程度反馈求精,通过隶属程度以逐渐逼近方式计算节点坐标区域。仿真实验结果证明,与RSSI和DV-Hop算法相比,新算法可以减少环境干扰和信号波动带来的影响,具有更高的定位精度和稳定性。     

基于矢量传感器的频率估计算法在水声通信中的应用

本文给出了基于矢量传感器的ESPRIT频率估计算法，并将其应用于频率调制水声通信系统中。与声强频率估计算法相比，ESPRIT频率估计可在小样本的情况下，获得高精度的频率估计。仿真和湖试结果表明，基于矢量传感器的ESPRIT频率估计算法可以提高通信速率并降低对通信系统的带宽要求。本算法对信噪比的要求较高，目前看，较适用于近程高速水声通信。     

基于模糊理论的多传感器数据融合测量

 针对多传感器数据融合过程中,各传感器可靠度估计困难的问题和如何对各传感器测量数据进行融合,提出了一种基于模糊理论的多传感器数据融合方法并研究了它在测量中的应用过程。该方法首先利用容许函数计算各传感器测量数据间的一致性以剔除系统误差数据,然后将测量数据进行模糊化,最后用模糊贴近度获得多传感器测量的数据融合结果。该方法计算简单,客观地反映了各传感器测量数据的一致性和可靠程度。测量应用实例验证了其在工程中的可行性,体现了稳定性和可靠性高的传感器在测量数据融合中的“优越性”,运算过程简洁、快速、有效,便于实时测量操作。     

模糊聚类信息融合算法在异构多传感器网络中的应用

在多传感器协同探测的应用背景下,提出将模糊聚类算法应用于多传感器网络的数据融合方向,解决异构多传感器网络由于各传感器探测信息粒度、时空不同而造成的航迹分裂和航迹冗余现象;通过仿真结果表明,该算法可以减少传统统计学方法错关联、漏关联的概率,对于复杂运动轨迹的机动目标(交叉航路目标)能够很好地进行多传感器测量数据的聚类,正确地进行测量数据的关联和融合,并进一步在通用航空监视管理系统的工程应用中加以验证;该算法在通用航空监管、物联网、协同探测信息系统方向均有广泛的应用空间。     

CMOS有源像素传感器辐射损伤对星敏感器星图识别影响机理与识别算法

为分析恶劣空间辐射环境导致星敏感器性能退化、姿态测量精度降低的原因,深入研究了⁶⁰Co-γ射线辐射环境下互补金属氧化物半导体有源像素传感器(complementary metal oxide semiconductor active pixel sensor,CMOS APS)电离总剂量效应对星敏感器星图识别的影响机理.通过搭建外场观星试验系统,实际观测天顶和猎户座天区,经过星图数据采集、星点提取与星图识别等试验流程,获得⁶⁰Co-γ射线辐照后CMOS APS噪声对星图背景灰度均值、识别星点数量的影响机理,并提出一种寻找被辐射噪声湮没星点的识别算法.通过理论推导分别建立了CMOS APS暗电流噪声、暗信号非均匀性噪声和光响应非均匀性噪声与星点质心定位误差的定量关系.研究结果表明⁶⁰Co-γ射线辐照后星敏感器星图背景灰度均值增大、星点识别数量减少, CMOS APS辐照后噪声增大导致星点质心定位误差增大,从而影响星敏感器的姿态定位精度,该研究结果为高精度星敏感器的设计和抗辐射加固提供一定的理论依据.     

基于误差修正的传感器阵列水声定位算法

本文分析了海洋环境中定位精度下降的根源,提出了一种基于误差修正的传感器阵列自主定位算法,并进行了计算机仿真和数据分析,结果表明该算法对于提高传感器阵列自主定位精度是有效的。     

一种非标定的快速星图识别方法

大多数现有算法在星敏感器光学系统参数标定不准确时,识别率显著降低。针对这种情况提出了一种无需标定参数的识别算法。该算法引入比例距离作为径向特征,角度作为环向特征。这两种特征不依赖焦距、主点等任何光学系统参数,仅和图像平面上的星点位置有关。识别时首先按照特征量进行初始匹配,然后利用FOV(Field of View)约束筛选待选星进行精确匹配。为了加快速度,精确匹配时引入了快速分组方法。仿真实验表明,该方法具有较快的识别速度,在没有光学系统参数的情况下,识别率可以达到97%。     

误差分散类彩色半调图的边缘检测算法

针对误差分散类彩色半调图提出一种边缘检测算法.首先应用K－L变换,将(R,G,B)空间转换为具有正交特性的彩色特征空间(I1,I2,I3),构造灰度图I使之包含所有单色图像的边缘信息,最后设计多尺度边缘检测模板以获取图像边缘.实验表明,算法较传统方法抗半调噪音的能力强,能快速、准确地提取彩色半调图像的边缘.     

An adaptively spatial color gamut mapping algorithm

To improve the accuracy of color image reproduction from displays to printers, an adaptively spatial color gamut mapping algorithm （ASCGMA） is proposed. In this algorithm, the compression degree of out- of-reproduction-gamut color is not only related to the position of the color in CIELCH color space, but also depending on the neighborhood of the color to be mapped. The psyehophysical experiment of pair comparison is carried out to evaluate and compare this new algorithm with the HPMINDE and SGCK gamut mapping algorithms recommended by the International Commission on Illumination （CIE）. The experimental results indicate that the proposed algorithm outperforms the algorithms of HPMINDE and SGCK except for the very dark images.     

Tau reconstruction and identification algorithm

CMS has developed sophisticated tau identification algorithms for tau hadronic decay modes. Production of tau lepton decaying to hadrons are studied at 7 TeV centre-of-mass energy with 2011 collision data collected by CMS detector and has been used to measure the performance of tau identification algorithms by measuring identification efficiency and misidentification rates from electrons, muons and hadronic jets. These algorithms enable extended reach for the searches for MSSM Higgs, Z and other exotic particles.     

Improved autonomous star identification algorithm

The log–polar transform(LPT) is introduced into the star identification because of its rotation invariance.An improved autonomous star identification algorithm is proposed in this paper to avoid the circular shift of the feature vector and to reduce the time consumed in the star identification algorithm using LPT.In the proposed algorithm,the star pattern of the same navigation star remains unchanged when the stellar image is rotated,which makes it able to reduce the star identification time.The logarithmic values of the plane distances between the navigation and its neighbor stars are adopted to structure the feature vector of the navigation star,which enhances the robustness of star identification.In addition,some efforts are made to make it able to find the identification result with fewer comparisons,instead of searching the whole feature database.The simulation results demonstrate that the proposed algorithm can effectively accelerate the star identification.Moreover,the recognition rate and robustness by the proposed algorithm are better than those by the LPT algorithm and the modified grid algorithm.     

A novel blind digital watermarking algorithm for embedding color image into color image

A robust and blind watermarking technique for dual color images is proposed in this paper. According to the energy concentrating feature of DCT, the two-level DCT is introduced and used to embed color watermark image into color host image, which is completely different with the traditional DCT. For reducing the redundancy of watermark information, the original color watermark image is compressed by the proposed compression method. After two-level DCT, nine AC coefficients in different positions of each sub-block are selected and quantified to embed watermark information. Moreover, only the extraction rules are used to extract watermark from the watermarked image without resorting to the original host image or watermark image. Experimental results show that the proposed watermarking algorithm can effectively improve the quality of the watermarked image and the robustness of the embedded watermark against various attacks.     

光纤传感颜色识别系统的设计与实现

利用光电传感技术进行颜色识别可以克服传统识别方法的许多不足,能辨别出微小的颜色变化并大幅度提高测试精确度。通过探测物体的后向反射光,一种采用反射式数字光纤传感器设计的颜色识别系统得以实现。由于不同颜色的被测物体对光信号吸收和反射能力不同,它可以根据反射光的强弱来识别颜色。实验证明采用光纤传感器可以实现近距离范围内对被测物体任意区域的非接触式测量,测量范围宽、测试精度高,在表面探测中具有很好的应用前景。     

A color correction algorithm for noisy multi-view images

A novel color correction algorithm for noisy multi-view images is presented. The key idea is to use the improved Karhunen-Loeve (K-L) transform to obtain correction matrix that can eliminate noise effect to the fullest extent. Noise variance estimation is first performed in the algorithm. In the end, wavelet transform is applied to denoise the corrected image. Experimental results show that, compared with traditional correction method, a well-performed correction result is achieved using the proposed method,and the visual effect of the denoised corrected image is almost consistent with ideal corrected image.     

采用三色传感器校正多台计算机显示器色彩效果一致性

介绍了一种采用三色传感器测量计算机阴极射线管(CRT)显示器色度信息的方法,并以此对显示器进行校准,从而实现多台显示器上同一图像显示色度一致。三色传感器得到的信号,经过A/D板采样进入计算机以实现图像信息的数字化,并用软件的方法对数据修正,简化了卢瑟条件对硬件系统的要求。实验证明,这样的系统满足多台显示器颜色一致性的校准要求。     

Blind identification of occurrence of multi-modality in laser-feedback-based self-mixing sensor

Self-mixing interferometry(SMI)is an attractive sensing scheme that typically relies on mono-modal operation of an employed laser diode.However,change in laser modality can occur due to change in operating conditions.So,detection of occurrence of multi-modality in SMI signals is necessary to avoid erroneous metric measurements.Typically,processing of multi-modal SMI signals is a difficult task due to the diverse and complex nature of such signals.However,the proposed techniques can significantly ease this task by identifying the modal state of SMI signals with 100%success rate so that interferometric fringes can be correctly interpreted for metric sensing applications.