Real-time quantitative optical method to study temperature dependence of crack propagation process in colloidal photonic crystal film

A real-time quantitative optical method to characterize crack propagation in colloidal photonic crystal film（CPCF）is developed based on particle deformation models and previous real-time crack observations. The crack propagation process and temperature dependence of the crack propagation rate in CPCF are investigated. By this method, the crack propagation rate is found to slow down gradually to zero when cracks become more numerous and dense. Meanwhile, with the temperature increasing, the crack propagation rate constant decreases. The negative temperature dependence of the crack propagation rate is due to the increase of van der Waals attraction, which finally results in the decrease of resultant force. The findings provide new insight into the crack propagation process in CPCF.

Established and Emerging Optical Technologies for the Real-Time Detection of Cervical Neoplasia: A Review

Cervical cancer remains a critically important problem for women, especially those women in the developing world where the case-fatality rate is high. There are an estimated 528,000 cases and 266,000 deaths worldwide. Established screening and detection programs in the developed world have lowered the mortality from 40/100,000 to 2/100,000 over the last 60 years. The standard of care has been and continues to be: a screening Papanicolaou smear with or without Human Papilloma Virus (HPV) testing;followed by colposcopy and biopsies and if the smear is abnormal;and followed by treatment if the biopsies show high grade disease (cervical intraepithelial neoplasia (CIN) grades 2 and 3 and Carcinoma-in-situ). Low grade lesions (Pap smears with Atypical Cells of Uncertain Significance (ASCUS), Low Grade Squamous Intraepithelial Lesions (LGSIL), biopsies showing HPV changes or showing CIN 1);are usually followed for two years and then treated if persistent. Treatment can be performed with loop excision, LASER, or cryotherapy. Loop excision yields a specimen which can be reviewed to establish the diagnosis more accurately. LASER vaporizes the lesion and cryotherapy leads to tissue destruction. Under long term study;loop excision, LASER, and cryotherapy have the same rate of cure. The standard of care is expensive and takes 6 - 12 weeks for the individual patient. During the last twenty years, new technologies that can view the cervix and even image the cervix with cellular resolution have been developed. These technologies could lead to a new paradigm in which diagnosis and treatment occurs at a single visit. These technologies include fluorescence and reflectance spectroscopy (probe or wide-field, whole cervix scanning approaches) and fluorescence confocal endomicroscopy or high resolution micro-endoscopy. Both technologies have received Federal Drug Administration (FDA) and have been commercialized. Research trials continue to show their remarkable performance. These technologies are reviewed and clinical trials are summarized. Emerging technologies are coming along that may compete with those already approved and include optical coherence tomography, optical coherence tomography with autofluorescence, diffuse optical microscopy, and dual mode micro-endoscopy. These technologies are also reviewed and where available, clinical data is reported. Optical technologies are ready to diffuse into clinical practice because they will save money and 3 or 4 visits in the developed world and offer the same standard of care to the developing world where more cervical cancer exists.

Electricity Price Influence Factors Analysis Using Stochastic Matrix for Real-Time Electricity Price Forecasting

Real-time electricity price( RTEP) influence factor extraction is essential to forecasting accurate power system electricity prices. At present,new electricity price forecasting models have been studied to improve predictive accuracy,ignoring the extraction and analysis of RTEP influence factors. In this study,a correlation analysis method is proposed based on stochastic matrix theory.Firstly, an augmented matrix is formulated, including RTEP influence factor data and RTEP state data. Secondly, data correlation analysis results are obtained given the statistical characteristics of source data based on stochastic matrix theory.Mean spectral radius( MSR) is used as the measure of correlativity.Finally,the proposed method is evaluated in New England electricity markets and compared with the BP neural network forecasting method. Experimental results show that the extracted index system comprehensively generalizes RTEP influence factors,which play a significant role in improving RTEP forecasting accuracy.

Features of aerosol optical depth and its relation to extreme temperatures in China during 1980–2001

Based on Total Ozone Mapping Spectrometer （TOMS） monthly aerosol optical thickness （AOT） measurements in 1980–2001 a study is made of space/time patterns and difference between land and sea of AOT 0.50 μm thick over China,which are put into correlation analysis with synchronous extreme temperature indices （warm/cold day and night）.Results suggest that 1） the long-term mean AOT over China is characterized by typical geography,with pronounced land-sea contrast.And AOT has significant seasonality and its seasonal difference is diminished as a function of latitude.2） On the whole,the AOT displays an appreciably increasing trend,with the distinct increase in the eastern Qinghai-Tibetan plateau and SW China,North China,the mid-lower Changjiang （MiLY） valley as well as the South China Sea,but marginal decrease over western/northern Xinjiang and part of South China.3） The AOT over land and sea is marked by conspicuous intra-seasonal and -yearly oscillations,with remarkable periods at one-,two-yr and more （as interannual periods）.4） Land AOT change is well correlated with extremely temperature indexes.Generally,the correlations of AOT to the extreme temperature indices are more significant in Eastern China with 110 ° E as the division.Their high-correlation regions are along the Southern China coastline,the Loess Plateau and the Sichuan Basin,and even higher in North China Plain and the mid-lower Changjiang River reaches.5） Simulations of LMDZ-regional model indicate that aerosol effects may result in cooling all over China,particularly in Eastern China.The contribution of aerosol change may result in more decrease in the maximum temperature than the minimum,with decrease of 0.11/0.08 K for zonal average,respectively.

Pearson＇s Correlation Coefficient： A More Realistic Threshold for Applications on Autonomous Robotics

Many applications for control of autonomous platform are being developed and one important aspect is the excess of information, frequently redundant, that imposes a great computational cost in data processing. Taking into account the temporal coherence between consecutive frames, the PCC （Pearson＇s Correlation Coefficient） was proposed and applied as： discarding criteria methodology, dynamic power management solution, environment observer method which selects automatically only the regions-of-interest; and taking place in the obstacle avoidance context, as a method for collision risk estimation for vehicles in dynamic and unknown environments. Even if the PCC is a great tool to help the autonomous or semi-autonomous navigation, distortions in the imaging system, pixel noise, slight variations in the object＇s position relative to the camera, and other factors produce a false PCC threshold. Whereas there are homogeneous regions in the image, in order to obtain a more realistic Pearson＇s correlation, we propose to use some prior known environment information.

Acceleration of optical coherence tomography signal processing by multi-graphics processing units

A multi-GPU system designed for high-speed,real-time signal processing of optical coherencetomography(OCT)is described herein.For the OCT data sampled in linear wave numbers,themaximum procesing rates reached 2.95 MHz for 1024-OCT and 1.96 MHz for 2048-OCT.Data sampled using linear wavelengths were re-sampled using a time-domain interpolation method and zero-padding interpolation method to improve image quality.The maximum processing rates for1024-OCT reached 2.16 MHz for the time-domain method and 1.26 MHz for the zero-paddingmethod.The maximum processing rates for 2048-0CT reached_1.58 MHz,and 0.68 MHz,respectively.This method is capable of high-speed,real-time processing for O CT systems.

A portable optical sensing system for rapid detection of fluorescence spectra

Development of a prototype of a portable optical sensing system is presented for fast detecting of samples’fluorescence spectra.A compact configuration is achieved by integrating a small spectrometer,a microcontroller,a Universal Serial Bus(USB)Host Shield,a network module,and a web server.The fluorescence spectra of a tested sample can be obtained.Then the test data are sent through network communication to our Cloud Server which can store the data for further analyses.With this configuration,test results can be revealed in a short time and downloaded by users to their laptops,tablets or cellphones anytime and anywhere.

一种单信标测距辅助INS的导航方法

传统基于地球物理场的匹配辅助惯性导航方法在基础数据变化特征不明显或数据缺乏等苛刻条件下,难以实现有效匹配定位。为解决这一问题,提出了一种单信标测距辅助惯性导航系统(INS)的方法。首先,在单信标测距解析基准图上引入相关极值匹配辅助导航算法并进行重新建模。然后,采用差分进化寻优算法对该模型进行解算,并设计了一种固定匹配序列长度的建模方法以解决相关极值匹配算法实时性差的缺点。所提方法在缺乏地球物理基础数据条件下,仅需在海底布放单只声信标即可实现局部海域水下高精度实时定位。同时,由于采用的测距基准图为解析形式,所提方法也能较好地解决离散匹配算法定位精度受限于基准图分辨率等问题。最后,设计了相关实测实验,实验结果表明当惯导定位误差累积为1529.4 m时,采用所提方法与单信标匹配,定位误差减小为111.8 m,算法的有效性得到了验证。

基于多因素分析的烘丝机智能调控研究

烘丝过程中影响出口烟丝水分和温度的干扰因素较多,为了保障出口烟丝水分与温度的稳定性,首先基于烘丝过程的历史数据,采用相关性分析方法对影响因子进行筛选。其次,选取出口烟丝水分和出口烟丝温度为目标值,通过对各机器学习模型的对比分析选取了能够快速建模与预测的极限学习机(extreme learning machine,ELM)作为建模方法,以通过模型求解运算,得出预测值。最后,采用模拟退火(simulated annealing,SA)算法,实时优化热风风速和排潮风门开度的设定值,实现对出口烟丝水分和温度的预测和控制。实验结果表明,极限学习机模型的预测效果良好,预测当前出口水分的均方根误差为0.015,出口温度的均方根误差为0.638,误差较小,保障了烘丝机智能调控方法的调控精度。

外测实时数据融合方法分析

针对目前任务模式复杂、测量装备种类多且跟踪能力不同的问题,充分利用汇集于中心的大量装备测量数据,改变原有的接力分段处理的方式,研究测元级和弹道级的实时融合处理方法,给出切实可行的数学模型和方法步骤,并模拟异常数据分别计算,分析两种方法的处理精度和适用情况。该方法已经在实时处理软件中使用,保障了多项任务的实时数据处理,较传统处理方式有明显提高。

气溶胶微生物粒子本征荧光计数仪器设计

针对气溶胶微生物粒子实时监测的需求,对基于微生物粒子本征荧光和光散射检测方法和装置进行了研究。分析了粒子光散射检测的基本原理,对微生物粒子荧光活性分子以及金黄色葡萄球菌等6种微生物进行了荧光光谱的测试和分析,确定了405nm激发光和双路散射光的整体设计方案。通过对气路和检测腔结构的重要参数仿真,实现了其优化设计,最后,完成了检测装置的构建。初步测试结果表明:该装置实现了对粒子散射光和荧光的同步探测,可以对普通尘埃粒子和微生物粒子进行区分和计数,为进一步开展气溶胶微生物粒子浓度的实时监测仪器研发奠定了基础。

网络安全风险评估方法研究综述

网络安全风险评估是构建网络空间安全体系的重要环节,可以有效保护个人和组织机构避免受到网络安全攻击。文中简要概述了网络安全风险评估理论,重点介绍了目前主流的网络安全风险评估方法,并根据不同的方法性质对现有方法进行分类和对比,分析了各方法的优缺点以及适用范围。在此基础上,文中归纳提取出对网络安全评估结果产生影响的因素并对网络安全评估领域未来的研究重点进行提议。分析结果表明,关联性和评估指标的不确定性以及评估过程的实时性这3个因素是影响风险评估效果的主要因素,并给未来的风险评估方法研究提供了参考依据。

基于DIC技术的钢筋混凝土梁剪切裂缝自动提取与量化方法

针对钢筋混凝土梁实验中剪切斜裂缝的自动化定位、全域范围内各方向宽度量化及扩展追踪问题,该文提出一种基于数字图像相关技术(DIC)的裂缝自动提取与宽度量化的计算方法。由DIC计算得出的水平、竖直、剪切应变场来计算试件表面的主拉伸应变场,并将试件表面主应变大于某一阈值的部分视为开裂。对开裂部分进行形态学操作,提取出裂缝骨架线。在骨架线两侧定义裂缝运动参考点,根据参考点的运动来计算裂缝的发展规律。该计算方法实现了混凝土梁加载过程中任意方向上裂缝自动化检测及高精度量化,并且能够处理试件局部旋转的问题,充分了利用DIC测量技术的潜力。通过实验室内四组钢筋混凝土梁剪切实验验证该方法的有效性与精度。结果表明:该方法能够在多加载阶段实时追踪全域范围内各方向的裂缝开展并量化。

计及新能源出力相关性的多能源微网仿射实时优化调度

为计及新能源出力相关性对多能源微网运行的影响,并响应源荷实时变化,提出一种计及新能源出力相关性的多能源微网仿射实时优化调度方法。首先,在多能源微网中引入Kalina循环,实现热电联产机组的灵活经济输出。其次,考虑源荷不确定性以及风光出力相关性对多能源微网运行的影响,构建并求解计及风光出力相关性的多能源微网仿射优化模型。再次,在获得优化方案变化范围的基础上,实时计算各仿射噪声元的取值,从而获取多能源微网实时调度轨迹。最后,仿真结果验证了所提方法能够充分计及不确定性和相关性的双重影响,有效应对源荷实时变化,并提升系统运行经济性。

基于Si_(3)N_(4)微环混沌光频梳的Tbit/s并行实时物理随机数方案

本文结合片上Si_(3)N_(4)超高Q微环的混沌光频梳和高速现场可编程门阵列,提出并实验验证了一种超高速的并行实时物理随机数方案.结果表明,Si_(3)N_(4)超高Q微环实验得到的光频梳齿包含数百个信道,通过调节Si_(3)N_(4)微环的工作状态使其处于光学混沌态,从而成为性能优良的物理熵源.采用现场可编程门阵列(FPGA)板载的多位模数转换器,对滤波后频梳的光混沌信号进行离散采样量化,生成8位二进制比特流.对该比特流进行实时的自延迟异或处理,并保留4位最低有效位,实验最终实现了单信道实时速率达5 Gbits/s的合格物理随机比特流.结合实验中数目达294的混沌光频梳齿,本方案的并行实时随机数的吞吐量可望达到1.74 Tbits/s.这些结果可为实时物理随机数源提供集成、超高速的新可选方案.

基于放大器优化的无中继通信系统研究

【目的】传统无中继通信系统中需要使用分布式拉曼泵浦放大器和遥泵放大器,而分布式拉曼泵浦放大器和遥泵放大器均需要使用高功率泵浦激光源,并且会提高无中继通信系统光学链路复杂度。针对这一问题,文章提出了使用高功率掺铒光纤放大器(EDFA)取代无中继通信系统中的前向分布式拉曼泵浦放大器的无中继通信系统架构。【方法】文章通过VPI仿真平台建模分析比较了所提无中继通信系统架构的传输性能并进行了实时无中继通信传输实验验证。【结果】仿真结果表明,使用高功率泵浦提高信号光入纤功率能够实现传统无中继通信系统中的前向拉曼泵浦放大增益效果,并且更适合配合波分复用(WDM)技术实现更高速率的无中继通信传输。通过实验还证实了采用仅使用EDFA泵浦放大结构的无中继通信系统能够实现500 km跨度距离10 Gbit/s速率下的单通道无中继通信传输,并且在结合WDM技术的情况下,能够实现4×10 Gbit/s速率、500 km光纤链路跨度下的通信传输。【结论】文章所提仅采用EDFA泵浦放大的无中继通信传输系统架构能够极大地简化传统无中继通信系统架构,且能够基于EDFA泵浦放大布置多通道WDM系统从而提升系统通信传输的信号速率,对未来无中继通信系统结构简化以及通信速率提升具有重要的实际意义。

光学相干层析成像技术在膜污染研究中的应用

简述了光学相干层析成像技术(Optical coherence tomography,OCT)的成像原理和监测优势;由于可快速生成高分辨率的污染层二维和三维图像,可用于表征污染层形成过程､定量分析污染层､表征膜内部污染与润湿､耦合深度学习模型预测膜污染,促进对膜污染形成过程和机制的理解;总结了OCT在膜污染分析中的主要问题,并对未来的研究进行了展望。

基于冗余第二代小波变换的光纤陀螺实时降噪算法研究

提出了一种基于冗余第二代小波变换的光纤陀螺实时降噪算法,该算法直接利用插值补零后的预测器和更新器对信号进行分解和重构,确保逼近信号和细节信号的长度与原始信号相同,避免重构后信号失真。模拟信号和光纤陀螺输出信号的仿真实验结果表明,该算法能够较好地保留信号的时域特征,保证信号的完整性和准确性,不受降噪过程的影响,同时量化噪声降低了约50.23%,角度随机游走降低了约19.14%,零偏不稳定性降低了约53.02%,为光纤陀螺信号处理提供了一种有效的方法。

超导磁浮轨道光纤传感监测系统的设计与实现

随着超导材料的发展,超导列车技术发展迅速,针对高温超导磁浮列车会在运行过程中对轨道系统造成影响以及强磁环境下传统电子学传感器难以实现稳定可靠测量的问题,设计了基于光纤传感器的高温超导磁浮列车轨道监测系统,以提高超导磁浮列车运行安全和稳定性。该系统主要包括传感器系统、数据采集及传输系统、智能化监测软件系统以及供配电系统。监测系统提供实时可靠的连续性数据监测,并由解调仪解算各通道传感器数据,通过TCP协议经局域网上传至服务器,由服务器上传至CCU(Central Control Unit)。该系统经过试验验证,实现了多台服务器数据交互、指令发送、在线监测以及数据读取工作,为高温超导磁浮列车可靠运行提供技术支持。

气吸式花生穴播器播种监测系统设计与试验

为解决花生膜上精量播种单粒率低、播种质量不稳定的问题,设计了一种基于对射式红外光纤传感器的气吸式花生穴播器播种监测系统,采用STM32F407VGT6单片机与编码器,收集速度脉冲信号、播种时间间隔信息,实现对播种单粒率、漏播率、重播率等播种质量信息的实时监测。试验结果表明,当传感器安装距离为3.1 mm,安装角度为3.2°时,播种监测精度最优,此时单粒监测精度为95.98%,漏播监测精度为95.91%,重播监测精度为93.28%;台架试验结果表明,当穴播器作业速度在3~5 km/h范围内时,单粒监测精度大于95%,漏播监测精度大于91%,重播监测精度大于90%;田间试验结果表明,在3~5 km/h作业速度内,单粒监测精度大于93%,漏播监测精度大于90%,重播监测精度大于88%。该气吸式花生穴播器播种监测系统能够满足花生播种过程播种质量实时监测的需求,为实际播种作业提供数据参考,保证播种全过程较高的播种质量。