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171.
张秀峰 《大连民族学院学报》2016,18(3):217-220
在分析了目前国内外钢轨磨耗检测技术的特点及方法的基础上,结合铁路工务段的实际检测需要,提出了小型钢轨损伤自动监测装置的整体方案。利用光电检测技术、微处理器技术及数据处理技术完成了检测装置的开发,并进行了试验测试,结果表明检测系统具有检测速度快、精度高、性能可靠的特点。开发的装置便于携带,具有人机对话功能,解决了目前检测设备普遍体积过大、携带不方便及检测效率低等问题。 相似文献
172.
《自然科学进展(英文版)》2019,29(6):655-659
A facile strategy for optical sensing of explosives with the assistance of 1,3,5-Triazine-2,4,6-triamine(MEL) in aqueous solution is proposed. Upon exposure to MEL, the electron-sufficient amino group in MEL was prone to form complexes with electron-deficient nitro group in explosives. The interaction could be tuned by the amount of MEL to fully consumed nitro-contained explosives dissolved in wastewater, thus prevented the gold nanoparticles(GNPs) from combining with MEL. In comparison with common detection method, the dose-response curve procedure reported here was in good linear relationship from 0 μM to 80 μM with good correlation factor(R~2= 0.9871), and was satisfactorily agreed with the proposed theoretical model. The detection limit(Lo D) was1.1 μM by spectrometer, 3.0 μM visualized by naked eyes and 21.3 nM by calculation. The procedure described in this study could be finished within a few minutes and showed its effectiveness in explosive detection upright on the gold surface in real wastewater, making this proposed method a powerful tool in several sensing platforms. 相似文献
173.
Occlusion problem is one of the challenging issues in vision field for a long time , and the occlu-sion phenomenon of visual object will be involved in many vision research fields .Once the occlusion occurs in a visual system , it will affect the effects of object recognition , tracking, observation and operation , so detecting occlusion autonomously should be one of the abilities for an intelligent vision system .The research on occlusion detection method for visual object has increasingly attracted atten-tions of scholars .First, the definition and classification of the occlusion problem are presented . Then, the characteristics and deficiencies of the occlusion detection methods based on the intensity image and the depth image are analyzed respectively , and the existing occlusion detection methods are compared.Finally, the problems of existing occlusion detection methods and possible research directions are pointed out . 相似文献
174.
徐红 《西安科技大学学报》2011,31(3)
在WLQC工地建设工程中,利用高密度电法对工地废弃水井进行探测,运用合理观测方式,结合高密度反演软件处理解释,查明了废弃水井的空间范围及其对施工的影响,取得了良好的地质效果.通过探测及时排除了给施工单位人员、设备带来的安全隐患并且为建设单位的设计提供了依据.实验结果表明在遇到水泥预制,场地勘探空间受到极大限制等施工工地的问题的勘测工作中,高密度电法具有成本低、效率高、效果好、显示直观等特点,不失为一种值得大力推广的好方法. 相似文献
175.
The fault detection problem for the nonlinear networked control system (NCS) with packet dropout and delay is investigated.A nonlinear stochastic system model is proposed to account for the NCS with random packet dropout and networkinduced non-uniformly distributed time-varying delay in both from sensor to controller (S/C) and from controller to actuator (C/A).Based on the obtained NCS model,employing an observer-based fault detection filter as the residual generator,the addressed fault detection problem is converted into an auxiliary nonlinear H∞ control problem.Then,with the help of Lyapunov functional approach,a sufficient condition for the desired fault detection filter is constructed in terms of certain linear matrix inequalities,which depend on not only the delay interval but also the delay interval occurrence rate and successful packet communication rate.Especially,a trade-off phenomenon between the maximum allowable delay bound and successful data packet transmission rate is found,which is typically resulted from the limited bandwidth of communication networks.The effectiveness of the proposed method is demonstrated by a simulation example. 相似文献
176.
The fault detection problem for the nonlinear networked control system(NCS) with packet dropout and delay is investigated.A nonlinear stochastic system model is proposed to account for the NCS with random packet dropout and networkinduced non-uniformly distributed time-varying delay in both from sensor to controller(S/C) and from controller to actuator(C/A).Based on the obtained NCS model,employing an observer-based fault detection filter as the residual generator,the addressed fault detection problem is converted into an auxiliary nonlinear H∞ control problem.Then,with the help of Lyapunov functional approach,a sufficient condition for the desired fault detection filter is constructed in terms of certain linear matrix inequalities,which depend on not only the delay interval but also the delay interval occurrence rate and successful packet communication rate.Especially,a trade-off phenomenon between the maximum allowable delay bound and successful data packet transmission rate is found,which is typically resulted from the limited bandwidth of communication networks.The effectiveness of the proposed method is demonstrated by a simulation example. 相似文献
177.
178.
研究了离散图像的连续表示及重建问题.首先利用弦理论,给出了图像的连续表示形式,然后利用付里叶变换实现了图像连续表示及重建的快速算法,接着将它们应用于图像无级缩放、图像平滑、边缘检测、角点检测,并与传统离散图像处理方法的实验结果进行了比较.实验结果表明:利用图像连续表示方法处理离散图像可以得到不差于传统的离散图像处理方法处理的结果,此方法使离散图像的解析法处理成为可能. 相似文献
179.
对象迁移自动机(OMA)是一种能够较好地解决话题识别与跟踪(TDT)中聚类问题的方法,但是,传统OMA模型由于聚类速度慢等缺点,难以满足TDT实时和增量聚类的要求.针对这一问题,本文一方面改进传统的OMA模型中自动机的动作设计,同时提出文档选择策略,加快了OMA的聚类速度.改进的方法在中等文档集上进行了实验,实验结果表明,该方法具有较好的聚类效果. 相似文献
180.
一种并联机构结构误差识别与修正的新算法 总被引:1,自引:0,他引:1
为了提高并联机床的运动精度,针对简化误差源模型(含42个误差量),基于并联机构位置正解的快速算法提出了一种结构误差识别的新算法.首先按理论并联机构设计参数,将一球杆仪的两个球铰分别固定在保持平行的动、静平台上,令球杆仪在动平台上的球铰中心相对于静平台上的球铰中心做球面螺旋线运动.然后在此前提下根据球杆仪球杆理论计算长度与实际长度之差构造m维矢量空间,依次让每一个待识别的结构参数有一个单位增量,重点修正与实测误差相关程度最高的结构参数.并通过从测量误差向量中分离出主修正向量后的残余误差向量方法提高修正效率.经过若干轮修正,直到使修正后球杆理论计算长度与实际长度基本一致,即可认为各项误差已修正完毕.该算法只需测量球杆的长度值,大大减少了测量工作量及由此而引入的误差源. 相似文献