焊接技术在锅炉安装领域的应用

本文分析了珠光体耐热钢的特点,探讨了珠光体耐热钢的焊接性。对产品结构、焊接材料、工艺过程进行了探讨。设计了12Cr1MoV、厚度40mm钢、焊条电弧焊的工艺评定的整个过程。为12Cr1MoV钢的焊接生产起到了指导作用。     

机器视觉系统发展及其应用

介绍了机器视觉系统的概念、特点以及系统的组成。重点阐述了机器视觉系统中的照明、镜头、相机等关键技术的发展现状。分析了机器视觉系统在工业、农业、医学等多个领域的应用情况,展望了机器视觉的发展趋势。     

履带轮转换技术的应用现状与发展趋势

介绍了可更换三角履带轮的结构组成、分析了其使用特点。主要包括轻便、低震动、低接地比压、高通过性、高行驶速度、可快速更换等。对可更换三角履带轮按照不同标准进行了系统的分类,分析了可更换三角履带轮的应用现状、发展前景,提出了其未来的研究发展趋势。     

精密加工系统综合实时监测技术研究

介绍了精密加工系统综合实时监测技术。论述了对机床的振动、主轴的位移、刀具温度、刀具切削力、旋转工件温度场进行监测的原理。重点介绍了监测系统的构成、监测方法、数据采集、数据分析和应用。     

基于FPGA系统重构技术的便携式多功能电子调试仪设计

介绍了FPGA系统重构技术,基于该技术设计了具有信号发生、波形显示的多功能电子调试仪。介绍了系统核心器件的选型原则、描述了系统的硬件结构。介绍了利用单片机对FPGA进行配置的原理及特点。给出了单片机及FPGA的程序设计思路。本系统具有体积小、价格低、实用性强的特点,特别适用于个人、户外使用。     

甘肃：2007年制造业信息化科技示范工程成绩显著

甘肃在“十五”甘肃省制造业信息化工程的基础上．分别调整了领导小组、专家组。同时兰州、天水、白银、酒泉、陇南等城市也调整成立了由分管市长为组长的制造业信息化领导小组和专家组．并制定了本地区制造业信息化科技工程实施规划。各示范、创建企业也分别成立了主管领导为组长的领导小组,设立了信息化主管。     

微机控制混砂系统的设计与研究(2)

介绍了以MCS-51系列单片机为微处理器的微机控制混砂系统的设计原理。分析了该系统的基本原理、单片机控制系统的硬、软件设计、抗干扰措施。机械部分的设计、关键参数的确定。同时给出了具体的实施途径,有效地解决了配料精度和良品率问题。     

热烈庆祝中国二重50华诞

…… 回顾历史,上个世纪中国二重从无到有,从小到大,创造了许多的中国第一,形成了以冶金设备、大型电站铸锻件、矿山设备、锻压设备、航空模锻件、火炮等为代表的主要生产线,为国民经济和国防建设提供了一大批急需的重大技术装备。发挥了不可替代的重要作用,为今后的发展打下了坚实的基础。     

酸碱系统机械密封的改进

分析了强酸、强碱输送泵机械密封失效的原因,阐述了相应改进措施。实施后杜绝了污染、降低了消耗、提高了装置的安全性和稳定性。     

摩擦学分会在徐州召开理事长会议

<正>中国机械工程学会摩擦学分会2014年理事长会议于4天敏副秘书长等人出席了本次会议。会议讨论了2017年世月27日在徐州召开,雒建斌院士、刘维民院士、葛世荣副界摩擦学大会有关工作安排。周仲荣副理事长介绍了2015理事长、黄兴副理事长、李健副理事长、严新平副理事长、年第十二届全国摩擦学大会的筹备情况,初步确定了会议周仲荣副理事长、张永振副理事长、孟永刚常务理事、邵时间与规模。会议还讨论了学会的其他工作。     

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.