光纤电压传感器传感头的设计

基于逆压电效应原理，介绍了光纤电压传感器的工作原理，提出了一种全新的传感头设计方案，为光纤电压传感器测量高电压提出了理论依据。     

DSP技术在光纤电压传感器中的应用

光纤电压传感可以用于电网电压的监测和保护,本文对体调制型电压传感器的原理进行了分析,并提出信息处理单元采用DSP技术新方法,讨论了整个系统的构成以及信息处理单元的硬件和软件结构,对系统的性能进行了分析并与信息处理单元采用80C196的传感器进行了比较,确定了本光纤电压传感器可以达到各项性能指标。     

光纤电压传感器信号处理电路的设计

介绍了光纤电压传感器的工作原理,研究了光纤电压传感器的信号接收与处理电路部分,设计并测试了放大滤波电路、模数转换及单片机的信号处理电路,对高压测量中的误差来源进行了分析。     

光纤电压传感器原理分析及其研制

光纤电压传感器可以用于电网电压的监测和保护。文中对体调制型光纤电压传感器原理进行了分析,提出了当考虑被测电压为交流正弦波时,有效值的线性测量范围大于瞬时值的线性测量范围,并分析了传感头各器件的取向对测量范围和非线性失真的影响。得到了提高信噪比的途径,确定了获得最高信噪比和最小非线性失真的最佳取向,并且提出了１／４波片和ＬＥＤ满足的条件。     

反射式光纤电压传感器

本文提出 一种结构简单、性能优 良且易实现光路自补偿 的反射式光纤电压传感 器,建立起了这种传感 器的理论模型,导出了 这种传感器的性能参数 分析式,借助计算机找出了这种传感器的性能极佳点集。     

光纤电压传感器在电力系统和电器设备中的应用

文中论述了光纤电压传感器在电力系统和电器设备中的各种应用、工作原理和特点。     

光纤电压传感器温度特性研究

本文介绍了光纤电压传感器温度特性和实验结果,提出了改善传感器温度特性的措施。     

电风车式光纤高电压传感器

基于高电压作用下电风车的转动特性以及光纤传输技术,提出一种电风车式光纤高电压传感器,介绍了这种传感器的基本结构,并给出其测量线性、稳定性的实验结果。这种传感器结构简单、成本低,可实现高电压的绝缘性测量。当环境温度为３０．２℃,相对温度为４８％时,传感器的线性测量为３．０～５．０ｋＶ,其测量结果的非线性误差低于３％。     

一种基于偏振调制的光纤电压传感器的研究

介绍了一种基于偏振调制的光纤电压传感器，并用Jones矩阵方法推出了其数学模型。采用补偿测量方案消除晶体自然双折射引起的误差；并使用高精度屏蔽变压器提高系统的信噪比。实验结果表明，其测量电压误差降为0．92％。     

电光型光纤电压传感器的研究

电光电压传感器（ＥＯＶＳ）可以用于电网电压的监测和保护。目前,ＥＯＶＳ存在的主要问题是其温度稳定性不好。本文从误差分析的角度分析了影响传感器稳定性及精度的主要因素,提出解决措施。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.