先进复合材料格栅制造工艺研究进展

概述了先进复合材料格栅结构的应用现状和潜在应用,分析了先进复合材料格栅结构制造工艺的共性问题和个性特征,按照赋形方式将先进复合材料格栅典型制造工艺划分为"硬模"工艺、膨胀垫工艺、膨胀块工艺、混合模工艺、互锁工艺、方管增强工艺、夹层互锁工艺,总计7类工艺,介绍了这7类工艺的基本原理,分析了这7类工艺的不足和适用范围,并针对工艺不足提出相应的改进措施。     

机械加工工艺过程资源环境属性清单分析与评价

根据机械加工工艺过程资源环境属性,分析了制造工艺过程清单分析步骤,并基于工艺的IPO过程模型,详细描述了清单分析评价指标建立过程与数据获取、评价方法。根据上述步骤和评价方法,建立了某刨削工艺清单分析表,综合评价该工艺的绿色性,从而为改善其资源消耗和环境影响提供依据。     

壳体零件的加工工艺

介绍了壳体零件的一般加工工艺划分、工艺的安排过程。结合典型壳体零件的工艺分析和加工技术要求,拟定了加工工艺路线。该工艺路线操作简单,可提高壳体零件加工的生产效率。对同类零件的工艺分析和工艺路线划分有指导意义,具有一定的应用价值。     

快速制造网格中全局工艺规划模块的分析与建立

基于快速制造网格平台,分析和建立了全局工艺规划模块,开发了全局工艺规划的分析工具包。该模块可以完成各种加工任务的全局工艺规划分析,确定每个任务的类别和全局工艺流程,实现任务分析的模块化。结合快速制造网格的应用实例发现,在实际运用中,全局工艺规划模块完全能够满足全局工艺规划分析的要求,对全局工艺规划决策具有重要的指导意义,验证了该模块的合理性与可行性。     

浅析普通加工工艺与数控加工工艺的教学接轨

简要地从数控工艺和普通工艺各自特点分析出发,讲述了如何把握好数控加工工艺内容的教学,如何实现大工艺背景下的数控工艺和普通工艺的结合,探讨了数控加工的工艺设计问题.     

机加工艺三维可视化表示与生成技术研究

为了将机加工艺以一种直观的、可视化的和可交互的方式展现出来,提出了三维可视化工艺的概念。通过分析三维可视化的机加工艺表示方法,建立了面向工艺过程的三维机加工艺信息模型。研究了在工艺信息模型支持下三维可视化工艺生成技术,提出以三维工序模型作为工艺信息载体来替换二维工序简图的思路。针对工艺模型分析了工艺信息的提取和组织方法。最后通过实例验证了方法的可行性和有效性。     

支持工艺创新的工艺专利分类方法研究

为快速获取适合创新设计的工艺专利,提出了一种面向工艺创新的工艺专利自动分类方法。在分析工艺创新需求和工艺专利特点的基础上,建立以工艺方法、制造对象和制造特征为依据的工艺专利分类标准,论述了应用文本挖掘技术的工艺专利分类过程,开发了工艺专利自动分类系统。以某航空发动机制造企业样本集进行分类测试及对比,最后通过实例分析了该专利分类系统在工艺创新设计中的应用。     

[绿色制造工艺和系统]复合材料电池箱真空辅助树脂灌注快速成形工艺

分析了几种复合材料零部件常规的制作工艺,针对电池箱的结构特点,提出了材料和结构一体化的真空辅助树脂灌注（VARI）快速成形工艺,并且采用液体成形模拟分析软件PAM-RTM确定了工艺方案和工艺参数。VARI工艺与传统双面模具的树脂传递模塑(RTM)工艺相比,节省了大量的工装设备和工序,降低了成本。为了验证所采用的工艺方法的可行性,实际制作了样件,结果表明所采用的工艺方法实现了快速、低能量消耗且绿色环保的目的。     

工艺FMEA和CAPP一体化设计及应用

研究了在CAPP(计算机辅助工艺设计)系统中嵌入工艺FMEA模块,实现工艺可靠性分析和工艺计算机辅助设计一体化技术.介绍了自主开发的CAPP软件功能结构、流程和主要模块的详细设计;研究如何在CAPP过程中,进行工艺FMEA分析的方法和软件实现;最后,利用某部件进行了应用验证.     

浅析CFTEC发动机缸体生产线及制造工艺

从CFTEC发动机的背景开始介绍,然后依次探讨、分析缸体生产线的特点和工艺流程,再分析缸孔的珩磨工艺和曲轴孔的铰珩工艺,体现了从福特公司引进的缸体生产线的工艺特色,最后讲述了缸体生产线将来的工艺发展趋势.     

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.