大数据背景下基于分布式LDA算法的生产模式识别

结合大数据时代背景,在车间已经实现信息化的基础上,自行设计构建出了一种基于Hadoop框架的车间系统架构,用于车间海量数据的存储和分析。运用HDFS存储车间产生的海量数据;借鉴控制图识别不同生产模式的方法,将Mapreduce编程模型与LDA算法相结合对存储在HDFS上的数据进行分析,实现了对异常生产模式的快速识别和对生产过程的实时监控,从而解决了产品在生产过程中产生的海量数据存储难、分析难的问题,并为上层决策提供了支持。     

基于NoSQL的PDM图文档存储

针对传统基于RDB的PDM系统在图文档存储管理中的诸多掣肘,文章着眼于图文档的妥善存储,将No SQL数据库加入以HDFS为基础的企业私有云存储平台,共同组建存储资源网。讨论了存储模型的设计思想并提出一种存储系统综合评判模型,通过实验并结合多维属性决策理论得出文件在No SQL和HDFS之间选择的存储阈值,实现数据分布存储,新的存储模型能够支持大文件的高效存储及小文件的快速响应。     

基于Hadoop的视频监控系统开发和应用

针对视频收集设备对于视频处理精度不断提高的需求,设计了基于Hadoop技术的视频监控系统.对视频监控系统的展示层、应用服务层、技术支撑层、平台接入层等进行分析,设计了系统的整体架构.根据视频监控系统的架构,主要包括存储接口、存储管理模块、录像存储模块、实时监控和历史回放等,设计了系统的数据库,其中包括用户表、视频分割表、视频数据库、用户访问视频数据库.通过系统测试表明:基于Hadoop的视频监控系统能够解决传统视频监控问题,且提高了系统监控安全性和有效性.     

基于区块链边缘计算的云端数据验证方法

提出了一个3层的物联网边缘计算的区块链云架构以及基于区块链技术的分布式云服务模型，构建了低成本、安全、按需访问的IoT智能计算基础框架。边缘计算节点使用SDN控制器，将计算资源边缘化，降低网络中的数据流量，并在物联网设备之间实现最小的端到端延迟和最优的计算资源利用。同时，提出了此架构下的云端数据保护机制，使用移动代理技术将分布式虚拟机代理模型部署在云中，让多租户相互协作以确保数据的完整性验证。虚拟机代理模型与默克尔哈希树生成文件相对应的唯一哈希值，通过区块链上的智能合约来实时监视数据变化，遇异常时向用户发出数据篡改警告消息，并用“质询-响应”模式构建云数据完整性验证方案。最后，在某电网公司的数字化基建(BIM)环境下部署了所提的区块链分布式云架构，通过实验分析了延迟、客户端响应时间和文件操作性能。实验结果表明，与集中云架构比较起来，所提方法具有更快的响应时间、更高的吞吐量和更小的文件操作开销。     

WEB方式将文件上传到ORACLE数据库的技术及实现

介绍了在基于J2EE的WEB架构下,将客户端文件上传至服务器,并直接以LOB类型存储在Oracle数据库的实现技术。     

大数据处理技术在生产质量跟踪中的应用

由于某特种印制企业每个工序产生的数据具有数据量大、多样性和实时变化的特性,传统的技术架构不能有效管理及分析。针对企业提出的将这些数据进行了收集与跟踪,并进行实时分析以优化生产工艺的需求,采取了基于Hadoop技术框架来构建生产跟踪系统,设计了大数据管理数据模型,实施了各工序的数据采集与迁移工作,开展了数据分析与可视化的工作。研究成果表明,在物联网环境下将大数处理技术应用于传统的生产跟踪与管理业务,具有很强的现实意义。     

基于大数据的列车部件智能制造系统

基于大数据技术对列车部件智能制造进行研究,首先介绍智能制造系统形成过程,包括制造业大数据特征、Hadoop分布式架构平台搭建过程;根据项目目标和要求,将智能制造系统架构确定为物物互联层、智能感知层、数据分析层、制造服务层和一个大数据中心,设计硬件拓扑结构。然后对数据采集、传输及分析等关键技术进行说明。最后基于ECRS对制造过程进行工艺分析,基于DELMIA进行装配运动仿真确定产线布局,利用CATIA对产线进行三维建模,对工装夹具进行重点设计研究。研究实现了列车部件制造的互联化、数字化、信息化和智能化目标,具有较大的研究价值和现实意义。     

基于Web Services架构的加工特征识别技术

提出了通过Web Services体系架构进行加工特征的网络化识别.整个系统由CAD文件特征识别功能服务模块,Web Services实现架构组成.在基于特征的CAD实体造型系统的基础上提出了一种继承式的特征识别方法.对于复杂的模型,利用这种方法并辅以交互式特征定义也可以取得良好的特征识别效果.通过WebServices实现了符合STEP标准的模型文件和加工特征文件在CAD系统、CAPP系统之间进行信息交换,从而实现了产品加工特征的网络化识别.     

基于P2P分布式开放资源管理服务的云存储方案研究

云存储技术因其能为用户提供了安全、海量、随时随地的数据存储功能而得以快速发展。提出了利用网络上现存的自然分布于世界各地的大量免费存储服务,如网盘、ftp、email以及其他形式等存储空间,将这些服务集中起来,为用户提供价廉、可靠的存储系统。介绍了一种低开销、快速度、高可用、可扩展的云存储拓扑系统,以期在该拓扑架构下实现以文件存储和共享服务为基础,不断扩展其他功能,最终形成P2P分布式存储资源共享的目的。     

基于Hadoop虚拟仿真教学管理系统研究

大数据时代的到来,针对Hadoop教学资源、实训设备等极度缺乏的背景,本文以Hadoop虚拟仿真教学管理系统研究为目的,结合教育技术与信息技术,采用Java Web开发技术,选用Mysql与HBase作为基础数据库,开发基于Hadoop的综合性实训平台,旨在实现教学管理、实验辅助教学管理、Hadoop课程资源以及其他课程资源开放性、共享性、职业性,实现教育资源普及更广泛、空间覆盖更大和智慧教育更突出,推动学校虚拟仿真实验室建设和创新实践教学改革。     

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.     

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....     

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.