利用西门子S7-200自由通讯接口实现与条码扫描枪的通讯

本文介绍了一种成本低廉,稳定可靠的串口通讯方式,利用小型可编集成的自由通讯接口实现与串口设备的通讯。详细描述了自由通讯口的通讯模式,给出了与条码扫描枪实现通讯的编程实例,为低成本实现通讯提供了一种解决方法。     

台达PLC与条码扫描装置的通讯

介绍了一种极具性价比且稳定可靠的串口通讯方式,利用台达可编程序控制器的自由通讯接口实现与串口设备的通讯。详细描述了台达PLC自由通讯口的通讯模式,给出了与条码扫描枪实现通讯的编程实例,为低成本实现通讯提供了一种解决方法。     

景区闸机异步串行通信协议的设计与实现

以景区闸机为设计平台,介绍了串行通讯协议的设计实现方法,包括通讯帧设计,通讯实现图设计,通讯状态设计及具体的编程实现。叙述了从帧结构设计到具体帧接收的实现方法,介绍了涉及到的相关技术,如环形缓冲区、队列和状态机。该方法对异步串行通讯协议的设计与实现有一定的参考意义。     

服务器与单片机系统无线通讯设计与实现

论述了一种通讯数传电台实现服务器与下位单片机系统间主从式无线联网方法,并根据通讯的需要制定了系统的通讯协议,实现主从地址的识别以及误码的判断。此外,采用单字节多次收发的方法,实现单片机与服务器系统的通讯。大量实验与现场应用表明,所制定的通讯协议可以完全地实现无线数传电台间多址通讯中数据的可靠接收和发送。     

短信通讯在远程环保实时监控系统中的应用

介绍了远程环保监控系统的三层结构.论述了其中通讯模块的实现,把通讯模块分成两块,一块是与硬件相联的无线通讯Modem与串口之间通讯的实现,一块是监控站层与监测点之间的通讯协议的实现.     

RIC-DNC数控设备远程异构通讯物联网研究

详细论述符合国情的机械制造行业数控机床DNC异构通讯物联网集成方案和方法,实现数控机床车间信息化、网络化集群管理。重点简述实现RIC-DNC数控机床异构远程通讯的三个特色功能平台;由RIC-DNC来实现串口通讯或网络通讯,实现远程数控机床异构通讯总体结构、数控机床异构DNC通讯、远程异地生产监察进行生产管理和集中化NC文档关联文件管理四个方面内容。     

基于CP341通讯模块的Modbus通讯

论文详细介绍了CP341通讯模块和Modbus通讯协议,在此基础上给出了使用CP341模块实现Modbus通讯的硬件及软件实现方法。     

基于89C2051单片机的热表通讯模块的开发

介绍了利用89C2051单片机开发某热表的通讯模块，并将其应用于实验用主从分布式控制系统中，实现了工控机同多个热表的串行通讯。阐述了串行通讯规程，利用单片机的普通I／O端口实现串行口功能的方法，从而解决了该单片机在实际的串行通讯应用中串口资源少的问题。通讯模块通过RS-485通讯方式实现了热表与工控机的远距离通讯。在充分利用单片机端口资源的基础上完成了工控机与多台单片机通讯。     

数控系统通讯协议参数与通讯软件设计

介绍了ＲＳ－２３２Ｃ串行通讯标准,通过多种数控系统通讯协议件参数的分析,建立数控系统与计算机通讯协议关系,经通讯软件设计,实现数控系统与计算机间通讯。     

CAN总线在自动生产线中的应用

主要针对CAN总线在自动生产线中的应用,详细介绍了系统控制功能的实现、通讯网络的构成、CAN用户通讯协议的设计以及通讯节点硬件及软件的设计方法,通过CAN总线使生产线的各站点之间实现了远距离、可靠、快速的通讯.     

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.     

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....     

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。     

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.