两层镀膜长周期光纤光栅传感器的特性研究

以光纤光栅耦合模理论为基础,提出一种两层镀膜长周期光纤光栅传感器的结构模型,一层是在光纤包层外镀的铜金属薄膜,另一层是在铜薄膜外再镀一层敏感薄膜.对该结构模型的模场特性和透射特性进行分析和模拟,明确了薄膜参数对其透射特性的影响.该结构模型既可以利用敏感膜折射率随外界环境变化而改变的特性,也可以利用金属膜层进行温度和应变...     

发明与专利

一种检测多巴胺的电化学生物传感器及其制备方法 【摘要】本发明公开了一种检测多巴胺的电化学生物传感器及其制备方法,该生物传感器是先采用电化学方法在铂盘电极表面电聚合包覆一层聚（3,4-乙烯二氧噻吩）薄膜,然后通过静电作用与纳米金结合而得。该生物传感器具有超强的稳定寿命,     

LiNbO3棱镜耦合双金属薄膜表面等离子共振传感器

高折射率铌酸锂(LiNbO3)(2.202)为棱镜耦合激发的角度调制型表面等离子共振传感器,利用反射率公式优化单层银膜、金膜和双层银/金膜传感器薄膜的厚度,分别计算了优化厚度的传感器在检测样品折射率为1.330时的共振角、灵敏度、峰值半宽度(FWHM)和品质因数(FOM),理论计算表明:双层金属薄膜,随着金膜厚度的增加,传感器灵敏度增加,但峰值半宽度增加,品质因数下降.综合考虑,选择银/金(41/5)优化组合,传感器品质因数为优化的单层金膜(47 nm)传感器品质因数的2倍以上,另外,与常用的BK7玻璃棱镜耦合相比,LiNbO3棱镜耦合具有较大的样品动态检测范围.优化厚度的传感器实验检测糖水浓度表明:糖水浓度与共振角为线性比例关系.     

一种检测多巴胺的电化学生物传感器及其制备方法

正申请号:201310047147.1【公开号】CN103149267A【公开日】2013.06.12【分类号】G01N27/48(2006.01)I【申请日】2013.02.06【申请人】河南省科学院高新技术研究中心【发明人】刘珂珂;刘清;褚艳红;刘冲【摘要】本发明公开了一种检测多巴胺的电化学生物传感器及其制备方法,该生物传感器是先采用电化学方法在铂盘电极表面电聚合包覆一层聚(3,4-乙烯二氧噻吩)薄     

用于化学气体检测的压阻检测式二氧化硅微悬臂梁传感器

文中演示了一种高分辨率的压阻检测式二氧化硅微悬臂梁传感器及其制作方法,并利用该传感器实现了对化学气体的检测.通过传感器在线检测以及其它表征手段,验证了该传感器通过单分子自组装方法获得敏感层的可行性.经过Cu2 /巯基十一酸单分子自组装层修饰的微悬臂梁传感器可以对甲基膦酸二甲酯(DMMP)气体进行快速响应,最小检测浓度可达数ppb(×10-9).     

基于位移电流的非接触式接近传感器

利用位移电流效应设计的非接触式接近传感器结构简单,单探测电极,不受静态环境影响,价格便宜.该传感器探头面积大小,延展距离,形状可根据需要任意设计,且传感器对厚度敏感并可透过物体进行探测.该传感器可用于微机电测量系统(MEMS),安保和材料内部缺陷的无损检测等应用领域.     

新颖的高灵敏度双金属层结构表面等离子波传感器的研究与优化设计

为了克服传统的表面等离子波传感器中金膜与玻璃棱镜基底附着力不足的缺陷,在金膜与棱镜之间增加一层银膜,从而有效地增加了金属膜与玻璃棱镜的附着强度,并增加了设计的自由度,通过基因算法对两金属层厚度优化设计,使得现在的设计不仅结构更加稳定,而且探测的灵敏度和线性度比起原有设计都得到有效提高.     

基于稀疏分解残差的氢气传感器故障探测与辨识方法

针对传感器故障探测和诊断,提出了一种基于稀疏分解残差的氢气传感器故障探测和辨识方法.基于信号稀疏分解理论,对采集的传感器正常信号数据集,利用K奇异值分解(K-SVD)学习算法得到一超完备字典D;在字典上对非正常(故障)信号进行分解,根据稀疏分解的残差大小和范围完成对传感器故障的探测及辨识.实验结果表明:对氢气传感器的故障探测率和总辨识率分别达到98.75%和97.25%,可以有效地解决氢气传感器的故障探测和辨识.     

自主移动智能金属探测器研制

为提升民用金属探测器探测精度和智能化程度,设计并制作了一种可自主移动探测的金属探测器.可自主移动的小车承载AY-LDC1000传感器探头,利用金属的涡流效应,采用STM32作为微处理器,检测探测频率的变化,并控制探测器自主移动,能在指定范围内自动、准确地探测出金属位置.通过实验检测该系统的可行性和稳定性,结果表明:探测器能精确自动探测出金属目标,且具有较高的探测率.     

基于电感数字转换器的金属探测小车设计

利用LDC1000电感数字转换器设计了一个金属探测小车。小车以MC9S12XS128单片机为控制核心,控制装有LDC1000电感传感器的摆臂左右摆动,进行金属探测。控制策略为先粗略扫描再精确定位,能在500 mm×500 mm的测试区域内探测到探头下方一定距离内的特定金属,并分辨出金属的不同特性。该金属探测小车探测精度高,测量信息准确、稳定,而且成本低,能适应多种恶劣环境,在军事领域、工业领域和安全领域都有很好的应用前景。     

SAR图象自动目标识别研究

目前,SAR已经成为一种不可或缺的对地观测和军事侦察手段.面对不断增长的SAR图象数据收集能力,如何对这些图象进行自动或半自动快速、准确地解译已经越来越引起人们的关注和重视.自动目标识别(ATR)是自动或半自动SAR图象解译研究的一个重要方面.SAR ATR过程可概述为:从观测得到的SAR图象中,找到感兴趣的区域(ROI),并计算出每个ROI的种类.为此,介绍了SAR ATR的含义及其一般流程,对SAR ATR系统按照它所采用的分类方法进行了归纳分类,分析了SAR ATR的难点,介绍了国内外SAR ATR的研究现状和发展趋势.     

基于噪声抵消与波束形成的小阵语音增强

为了提高麦克风小阵的语音增强效果,将阵列抗串扰自适应噪声抵消（ACRANC）方法与波束形成（BF）方法相结合,提出了一种效果更好的小阵语音增强方法。首先,通过生成多个ACRANC子系统,获得多路增强语音信号;然后,通过所提的自适应模式控制（AMC）算法和延迟求和（DAS）波束形成方法进一步提高多路增强语音信号的增强效果。对提出的方法进行了计算复杂度估计,验证了所提方法可以通过普通芯片实时实现。实际环境下的实验结果也表明,所提方法的语音增强效果相较ACRANC方法有所提高,具有一定的优越性。     

Structural optimization of finite deformation elastoplasticity using continuum-based shape design sensitivity formulation

A continuum-based shape design sensitivity formulation and optimization method is proposed for finite deformation elastoplasticity. In response analysis, the multiplicative decomposition of the deformation gradient into elastic and plastic parts is used for the hyperelasticity-based elastoplastic constitutive model with respect to the intermediate configuration. In design sensitivity analysis, the shape variation at the undeformed configuration is taken using a design velocity concept and then is transformed to the current configuration to recover the updated Lagrangian formulation. The design sensitivity equation of the direct differentiation method is solved at each time step without iteration. The effect of using different reference frames for response analysis and sensitivity analysis is discussed in detail. The path-dependency of the sensitivity is due to the evolutions of the intermediate configuration and the internal plastic variables. A numerical example is shown to confirm the accuracy and efficiency of the proposed computational method using a vehicle bumper optimization.     

结合滤波和深度玻尔兹曼机重构的指纹增强

指纹图像增强,是自动指纹识别系统中的重要环节.为弥补传统指纹图像增强算法的缺陷,提出一种指纹图像增强算法.在指纹块质量分级机制和复合窗口策略下,指纹图像首先在频域被具有方向选择性的方向高斯带通滤波器滤波增强;随后,二值增强指纹中的误增强区域在空域被具有方向选择性的深度玻尔兹曼机（DBM）重构.提出的方法结合了传统指纹增强算法与深度学习算法的优点,拥有很强的容错能力,能够完成对低质量指纹图像的有效增强.为了验证提出算法的性能,在公开的指纹数据库FVC2004上进行了大量实验,实验结果表明,相比于传统的指纹增强算法,提出的方法具有很强的鲁棒性,对高质量和低质量指纹均有不俗的增强表现.     

Visual comfort enhancement in stereoscopic 3D images using saliency-adaptive nonlinear disparity mapping

Perceptually salient regions have a significant effect on visual comfort in stereoscopic 3D (S3D) images. The conventional method of obtaining saliency maps is linear combination, which often weakens the saliency influence and distorts the original disparity range significantly. In this paper, we propose visual comfort enhancement in S3D images using saliency-adaptive nonlinear disparity mapping. First, we obtain saliency-adaptive disparity maps with visual sensitivity to maintain the disparity-based saliency influence. Then, we perform nonlinear disparity mapping based on a sigmoid function to minimize disparity distortions. Finally, we generate visually comfortable S3D images based on depth-image-based-rendering (DIBR). Experimental results demonstrate that the proposed method successfully improves visual comfort in S3D images by producing comfortable S3D images with high mean opinion score (MOS) while keeping the overall viewing image quality.     

基于CUDA的多尺度Retinex图像增强算法实现

多尺度Retinex图像增强是一种基于色彩恒定理论的图像增强算法,算法增强效果好,但随着图像分辨率的提高计算时间显著增加。分析并利用计算统一设备架构(CUDA)图形处理器(GPU)的并行处理特性,提出了一种基于CUDA的多尺度Retinex图像增强并行算法,将多尺度高斯滤波、对数空间差分和动态范围压缩等计算非常耗时的模块采用并行方式放在GPU中进行计算。实验结果表明所提算法能显著提高计算速度,随着图像分辨率的增加,最大加速比超过100倍。     

A spectral imaging array biosensor and its application in detection of leukemia cell

A new type of array immunosensor was developed by combining surface plasmon resonance (SPR) and spectral imaging techniques. The system consisted of a monochromator as the wavelength scanning light source, a polarizer, Kretschmann-Raaether attenuated total reflection (ATR) configuration including array sensor chip, and a CCD camera. The images of transmitting light from ATR were recorded versus the wavelength. By averaging gray scales of the pixels in the area of every gold spot from the image series, the complete spectral resonance curve of all sensing spots on the array can be extracted in parallel. The performance of the developed system was evaluated by analyzing interactions of the anti-CD33 monoclonal antibody to its target leukemic cells using 11 cases of human bone marrow specimens. The specimens were also analyzed with flow cytometry method (FCM) for comparison. The initial results measured by the immunosensor array were corresponded with that of FCM, indicating that the developed parallel method might be clinically suitable for immunophenotyping of acute leukemias. The new sensor array system showed the merits of high-throughput, high sensitivity, high specificity, label free and operation convenient. Spots numbers of the array could be increased if suitable technology were adopted for manipulating the micro bio-liquids on the sensor array chip.     

基于非下采样Shearlet变换与模糊对比度的合成孔径雷达图像增强

针对合成孔径雷达（SAR）图像在成像和传输过程中引入噪声和干扰从而导致图像清晰度下降、细节丢失等问题,提出了一种非下采样Shearlet变换（NSST）与模糊对比度的SAR图像增强算法。首先,原始图像经NSST分解成一个低频分量和若干个高频分量;然后对低频分量进行线性增强以提高整体对比度,对高频分量采用阈值法进行增强以去除图像中的噪声;接着对处理后的两部分分量进行NSST反变换得到重构图像;最后采用模糊对比度算法对重构图像进行增强,提高图像细节信息和层次感,得到增强后的图像。对40幅图像的实验结果表明,与直方图均衡化、多尺度Retinex增强算法、基于Shearlet变换和多尺度Retinex的遥感图像增强算法、基于剪切波域改进Gamma校正的医学图像增强算法相比,该算法的图像峰值信噪比至少提升了22.9%,均方根误差至少降低了36.2%,能明显提升图像的清晰度,使图像的纹理信息更加清晰。     

FGS视频流的码率分配算法研究

该文针对精细可分级编码(FGS)比特流在时变带宽网络上的传输，提出了一种基于视频序列率失真(R—D)特性的FGS增强层的优化码率分配算法。首先建立一个在多帧图像增强层之间进行码率分配的最优化问题形式，并进行了合理地简化，然后利用线性内插原则建立描述各帧图像增强层率失真特性的R—D模型。由于各帧图像R—D曲线的单调特性，如此建立起来的最优化问题可以用简单的算法求出最优解。仿真结果表明，这个方案在保证解码视频质量恒定和保持视频总体质量最优两方面均收到了良好的效果，同时本方案的简易性使得它的实现和应用成为可能。     

A mathematical framework to optimize ATR systems with non-declarations and sensor fusion

Combat identification is one example where incorrect automatic target recognition (ATR) output labels may have substantial decision costs. For example, the incorrect labeling of hostile targets vs. friendly non-targets may have high costs; yet, these costs are difficult to quantify. One way to increase decision confidence is through fusion of data from multiple sources or from multiple looks through time. Numerous methods have been published to determine a Bayes’ optimal fusion decision if decision costs are well known. This research presents a novel mathematical programming ATR evaluation framework. A new objective function inclusive of time is introduced to optimize and compare ATR systems. Constraints are developed to enforce both decision maker preferences and traditional engineering measures of performance. This research merges rejection and receiver operating characteristic (ROC) analysis by incorporating rejection and ROC thresholds as decision variables. The rejection thresholds specify non-declaration regions, while the ROC thresholds explore viable true positive and false positive tradeoffs for output target labels. This methodology yields an optimal ATR system subject to decision maker constraints without using explicit costs for each type of output decision. A sample application is included for the fusion of two channels of collected polarized radar data for 10 different ground targets. A Boolean logic and probabilistic neural network fusion method are optimized and compared. Sensitivity analysis of significant performance parameters then reveals preferred regions for each of the fusion algorithms.