软件冗余现场总线控制系统的研究

对比了当前国际上比较流行的DCS(分布式控制系统)和FCS(现场总线控制系统)的优点和缺点。对基于西门子S7-300系列PLC的软件通讯式冗余现场总线控制系统进行了十分细致的研究，根据大量相关资料和实践体会。深入剖析其软件冗余技术的内在机制和局限性。指出基于软件冗余同步现场总线控制系统具有可靠性高。利于国内自主开发等优点。为今后开展此类技术研究的工作人员提供了参考。     

一个基于Profibus的传动控制系统

介绍了一个以S7300PLC的CP342-5作为主站,通过Profibus现场总线与另一个PLC、直流调速装置及变频器三从站进行通信,并通过WinCC来监控的例子.清晰地说明了Profibus现场总线中PLC与PLC、PLC与传动装置通信网络中的硬件设置和软件构成.     

固定式钴-60集装箱检查系统安全联锁设计

简要介绍了PLC的特点，并详细讨论了用基于PROFIBUS现场总线技术的PLC实现固定式钴-60集装箱检查系统安全联锁控制的硬件结构，软件功能设计。     

PROFIBUS总线在污水处理自控系统中的应用

以西门子PLC S7为例讨论了PLC和现场总线技术，着重分析了其基本特性和相关产品在污水处理自动化控制系统中的应用。     

基于现场总线技术的PLC控制系统研究

研究、应用现场总线技术支持下的PLC控制系统,是目前工厂自动化得以实现的有效途径之一。在概述PLC通信功能和现场总线基本特征的基础上,结合应用成果,就PLC专用现场总线、基于Profibus的PLC控制系统以及CAN总线支持下的PLC控制系统进行了详细论述,总结并提出了制造业信息化进程中PLC控制系统的发展方向。     

PLC与现场总线技术在工业液体混合控制系统中的应用

文章针对传统工业液体混合控制系统落后的电气控制方式的缺点,采用了PLC、PROFIBUS-DP现场总线的自动控制技术,并对系统的生产工艺、系统的软件硬件选型、系统PLC程序设计的主要流程以及系统PROFIBUS-DP现场总线的设计进行了较为详细地阐述与说明。     

现场总线高效方便的无缝系统集成自动化新技术

结合工程应用实例，介绍Profibus-DP现场总线技术的特点并结合SIEMENS S7-300 PLC、ET200M及Phoenix Fieldline FLM IP67等相关产品组建Profibus-DP网络，阐述了Profibus-DP现场总线组态、系统集成构成DCS的方法。     

五站式MPS触摸屏的研究和应用

在介绍了模块化生产加工系统MPS结构和功能的基础上,着重研究了运用EV触摸屏组态与PROFIBUS-DP现场总线对MPS系统的改造。S7-300PLC作为主站通过总线与S7-200PLC通信,触摸屏通过MPI适配器与S7-300PLC通信,构成控制网络;通过EV5000组态软件实现触摸屏组态,完成对MPS系统现场单元的动态过程监控。     

基于基金会现场总线高速以太网的软PLC设备的研制

基金会现场总线（FF）对离散信号的处理能力不强，需要在其上集成PLC以弥补其不足。为此，研制了基于基金会现场总线高速以太网（FF HSE）的软PLC设备。阐明了该设备的系统组成、工作原理、开发系统和目标系统的设计与实现方法。提出了一种新颖的设计方案：在软PLC目标系统中采用2个嵌入式控制器分别实现系统的通信与控制功能。用于通信功能的嵌入式控制器把软PLC的分散控制功能集成到了基金会现场总线上。实验结果表明，设备对高速离散信号的处理能力强，能够无缝地集成于FFHSE上，有效地增强了FF现场总线控制系统对离散信号的处理能力。     

现场总线技术在BOPP薄膜生产线中的应用

一 系统简介 聚丙烯双向拉伸薄膜生产线由法国DMT公司总承包，控制系统采用施耐德公司TSX P574823M PLC，上位机采用监控软件iFIX，现场应用了ASI、WorldFIP、Profibus、Interbus等几种现场总线。这套控制系统中，最底层采用ASI现场总线控制，用简单经济的方式将自动化控制层的最底层的执行器和传感器连接起来，     

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.