基于Pro/E自顶向下的贴胶机设计

在分析贴胶带机工作原理的基础上,阐述了运用PRO/E骨架模型进行贴胶带机自顶向下的结构设计过程,并提出了多级骨架和并行骨架共同建模的方法。设计过程中,以骨架为媒介,用发布几何和复制几何的方法实现装配结构的整体数据关联性,从而确保贴胶机设计的合理性和装配的准确性。设计结果表明:采用自顶向下设计方法能够方便的建立并行设计系统,实现产品模型参数化设计和产品快速变更设计,提高设计效率。     

利用关键路径法对产品并行开发过程模型进行分析与优化

并行工程是集成地、协同地设计产品的系统化工作方式,而产品并行开发过程是系统化工作方式的集中体现.因此,有效地组织与管理产品并行开发过程是企业成功实施并行工程的关键.通过运用关键路径法和绘制网络图对过程模型中活动进度安排进行分析,并且以时间-成本为目标对过程模型进行优化.     

支持并行设计的维修性模型及其实现

为使装备具有良好的可维修性,提出了支持并行维修性设计的总体框架,分析了实现这一目标的关键和瓶颈技术———建立集成的产品维修性信息模型;以集成产品装配信息模型为基础,建立了集成的维修性信息模型,并讨论了与过程模型的集成;选择Pro/Intralink作为产品数据管理平台,分析了支持并行维修性设计集成环境的实现,包括基本环境的配置、主信息模型的建立、设计流程的定义与管理;以一种维修性分配工具的开发与集成验证了论文提出的方法。     

产品并行开发过程建模研究

并行工程的关键是对产品实行集成的并行开发,而产品并行开发过程模型是实现产品并行开发过程管理的 基础。本文从产品视图、功能视图、工作流程视图、组织视图、约束视图和资源视图多个侧面建立产品并行开发过程 集成模型,并详细研究了反映产品并行开发过程本质的组织视图、工作流程视图和约束视图模型的建立,建立了矩 阵式IPT组织模型以及产品并行开发工作流模型和多层约束网络模型。     

铁路货车并行开发使能技术与工具

提出了铁路货车过程管理、协调与冲突仲裁方法、信息集成建模,数据管理和评价工具等有关产品并行开发的使能技术和工具,提出了基于WindchillPDM集成各个使能工具的铁路货车产品并行开发体系结构。实践证明,铁路产品并行开发可提高产品质量,缩短开发周期,降低开发成本,提高企业的市场竞争能力。     

十字轴式万向联轴器参数化CAD系统开发

分析十字轴式万向联轴器CAD系统的功能需求,提出了该软件开发的总体功能框架,主要包括用户管理、产品绘制、产品设计、文档管理和技术接口等功能模块.针对CAD系统产品数据的类型、属性和联系进行了概念建模,建立了E-R模型图.基于统一建模语言UML建模方法,对CAD系统进行了用例分析建模.利用Visual Basic 6.0的ActiveX Automation技术和SQL Server数据库技术开发出了十字轴式万向联轴器参数化CAD设计软件,并给出了其应用实例.     

面向产品生命周期管理的装备交互式电子技术手册建模

回顾了交互式电子技术手册的发展历程,指出当前交互式电子技术手册创作过程尚未纳入到装备并行研发过程中,产品生命周期管理作为并行工程的一种使能技术和软件平台,可以作为装备交互式电子技术手册的数据源及管理平台.讨论了装备研发过程中传统的交互式电子技术手册开发流程存在的明显不足,提出了基于产品生命周期管理的交互式电子技术手册并行创作流程.分析了装备全寿命周期过程中的交互式电子技术手册活动,构建了基于主题的三层交互式电子技术手册内容数据模型和支持交互式电子技术手册的装备综合信息模型.提出了基于产品生命周期管理的交互式电子技术手册创作系统的总体框架,定义了交互式电子技术手册系统中的数据模块及其与产品生命周期管理系统中各种数据的映射关系,并阐述了其中的关键技术.最后,开发了交互式电子技术手册创作及显示系统,并进行了实例验证.     

基于层次链的产品装配过程建模方法

针对虚拟装配中装配过程模型信息表达不完整的问题,提出了一种基于层次链的产品装配过程建模方法.该方法引入装配任务和装配操作模型,通过粗粒度的装配任务与细粒度的装配操作相结合的装配过程建模,实现了虚拟装配中装配过程信息的完整性表达.该方法采用并行的装配操作,实现了对非线性装配过程的建模;引入调整零部件和拆卸零部件两种类型的装配任务,实现了对非单调装配过程的建模.此外,通过基于层次链的装配过程建模方法,实现了装配过程回溯、重做和回放等装配过程信息地管理和重用.最后自主开发了原型系统,并对相关算法进行了验证.     

面向开发过程的产品结构模型多视图应用

为满足开发过程产品结构数据的动态结构配置、动态任务协作、动态目标求解、动态状态跟踪等应用需求,提出了面向开发过程应用的产品多维模型空间,在此基础上,建立了面向开发过程的产品结构模型;在分析产品结构时域行为特征的基础上,给出了该模型的时域扩展定义;充分考虑该模型在开发过程中各应用视图的应用需求,提出了产品结构面向开发过程的多视图应用框架,并进一步分析了产品结构的多级应用模式.以产品结构的多视图应用框架为依据,分别探讨了时间节点视图上的动态状态追踪方案,以及研发主体视图、研发任务视图上的分布应用方案.结合某产品研发,建立了产品结构的多视图应用实例,初步验证了该模型的有效性.     

面向机械产品全生命周期的广义优化设计集成系统

在分析复杂机械产品设计需要和传统优化设计不足的基础上，提出了面向对象的机械产品分层结构模型和建模方法、分层—并行—集中的优化策略等新思想和新方法，从而构造了一种面向机械产品全生命周期的广义优化设计集成系统。     

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.