基于北斗定位系统的工程机械挖掘机显控终端设计

针对我国北斗卫星导航定位系统在工程机械上的应用,提出了一种基于北斗系统的挖掘机显控终端的设计方案。该方案在选定的高性能工业级32位Cortex-M3 LPC1788BD208 120MHz控制器的外围,配置了GPRS无线通信模块、BD2/GPS双系统定位模块和电源管理模块等,构建整个应用装置的硬件平台。该硬件平台可实现状态显示、数据采集与传输、定位导航、故障检测等功能,终端采用军用加固绑定、高亮显示等技术,实现阳光下可视,满足工程机械挖掘机应用的特点。     

多参数监测与视频监控一体化远程环境报警终端设计

实时准确掌握环境因素对于保障特高压换流站电气设备安装调试与安全可靠运行具有重要的意义。利用环境参数采集与视频监视等多种系统的结合,设计了一种多参数监测与视频监控一体化的远程环境报警终端。该终端能够实现现场区域视频监视和环境质量参数实时监测和显示,并在环境参数越值时发出声光报警和通过网络传送到移动终端以提醒用户接收报警信息,已在锡盟换流站投入使用并为换流阀的安装和调试提供了全过程技术保障,也为其他场所的环境监测与报警提供了良好的借鉴作用。     

高速装载机的电子监测系统及其常见故障排除

工程机械配装电子监测系统,可让使用维修人员实时了解和掌握工程机械技术状况,及时发现并排除故障,能最大限度地提高工程机械使用效率。宇通重工生产的GJZ112型高速装载机配置了智能化电子监测系统,该系统具有状态监测、故障诊断和智能报警等功能,现简介如下。     

军用工程机械散热系统性能控制的研究

本文首先对国内外军用工程机械散热系统相关技术的研究现状和发展趋势进行了综述和分析,以军用柳工50装载机为例,介绍军用工程机械散热器监测系统的应用情况,设计了实验监控系统并利用WinCC设计了散热系统的控制系统。本系统不仅可以对散热系统中单个零部件的性能进行测试,更重要的是可以测试散热系统的匹配性能。     

轴承性能监测试验台远程控制系统的研究

在传统轴承性能监测试验台的操作系统中,监测到的试验数据都是在PC端显示,而PC端是一个固定终端,这给试验带来一定的局限性。基于此缺点,将操作系统设计在移动终端,设计出了一个更有效的监测系统,即轴承性能监测试验台远程控制系统。此系统在传统的监测试验台系统上,采用无线通讯模块,将试验数据通过无线传输与智能手机进行关联,进而在移动终端能够显示试验数据,当数据异常报警时,在移动终端能够对系统进行远程控制。测试显示,该远程控制系统对试验台的监测控制具有实时性、准确性、可靠性。     

基于GPRS的工程机械远程监控系统设计

为了降低工程机械的故障发生频率并提高机器的维修效率,开发了基于GPRS网络的工程机械远程监控系统。系统以三菱PLC为控制器,GPRS DTU为通信工具,Delphi开发的软件为终端操作界面,实现了对现场作业工程机械关键参数的采集、分析、远程传输和报警。     

工程机械热管理系统设计与分析

在高原和高寒等极端气候与自然环境下,常规的车辆冷却系统难以满足工程机械车辆的工作需求。因此热交换和热平衡技术应用方面的研究显示日益重要。研究了热管理技术及其应用,包括系统集成和关键部件的设计等。提出了工程机械的整机热平衡技术方案。以某型军用推土机为例,对其原有的冷却系统进行了试验研究,应用复合式散热器与热管理技术重新设计了其冷却系统。利用FLOWMASTER流体力学仿真软件进行了原冷却系统和改进后的热管理系统的性能模拟,结果表明新系统具有较高的散热效率和使用良好热平衡效果。也表明热管理技术在军用和民用工程机械上都有良好的应用前景。     

基于无线传输的军用机械化桥梁在线监测研究

根据军用机械化桥梁在线监测技术指标要求,提出了在线监测的无线传输网络结构方案,进行了主控单元、电源模块、信号采集模块、无线传输模块等硬件设计.应用实例表明,开发的在线监测系统实现了适应野外作业条件下对军用机械化桥梁工作状态的在线监测以及故障的实时监控、定位和报警.     

基于北斗系统的军用工程机械群位置信息采集与传输系统设计

遂行大型工程保障任务的军用工程机械群的指挥控制一直是制约作业效率与质量的难点问题。针对军用工程机械群遂行大型工程保障任务时出现的各机械位置不明、动向不清等指挥管理问题,设计了一种基于北斗系统的军用工程机械群位置信息采集与传输系统,并进行了相关理论分析和方案设计。此系统基于车载端与指挥端内置的北斗模块,通过北斗短报文功能实现位置信息的采集、传输与显示,从而便于指挥员掌握装备的分布情况,提升指挥调度效率。     

高技术条件下的军用工程机械

在未来作战行动中,部队的机动能力、突击能力将空前提高,从而对工程保障不断提出更高的要求。作为保障机动性、提高部队野战生存能力的主要技术装备一一军用工程机械所完成的作战保障任务更繁重,随机性更强。这一切都迫切要求军用工程机械在设计、制造、使用及维护保养等各个方面引进现代先进技术,以使我军工程机械的装备水平有一个全面的提高。 我军工程机械装备现状与发展 军用工程机械是工程兵完成这行工程保障的主要技术装备,涉及到道路、桥梁、渡河、伪装、筑城、给排水、地雷及爆破等多项综合技术。近几年大批国内工程机械设计单…     

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.