共查询到18条相似文献,搜索用时 140 毫秒
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在现场检测工作的基础上,总结了井水源热泵系统在工程中常出现的一些故障问题,分析了造成故障的原因,并提出了解决的办法;探讨性地提出一些水源热泵系统现场检测和评价方法。 相似文献
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为有效提升输电线路的安全性,本文设计了基于云计算的无人机输电线路架空地线断股故障修复系统。在硬件方面,对无人机控制器和图像处理模块进行了电路设计;在软件方面,分析了地线断股的原因,使用无人机对输电线路进行故障定位,并建立了云计算平台,以实现无人机输电线路架空地线断股故障的修复。通过对比试验证明了系统的先进性,试验结果表明,该系统修复地线断股所用时间更短,系统性能更优越。 相似文献
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基于神经网络的组合预报模型及其应用 总被引:5,自引:0,他引:5
时间序列预报是神经网络的一个应用领域,多数研究集中在神经网络直接预报方面。本文从故障预报角度研究了神经网络组合预报模型,由神经网络给出常规预报方法的最佳组合。首先从函数逼近角度阐述这种模型的理论依据,在此基础上给出了模型的评价指标和神经网络的有效训练算法,最后给出在空间推进系统上的应用实例。 相似文献
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E.E. Hurdle 《Reliability Engineering & System Safety》2009,94(9):1371-1380
For conventional systems, their availability can be considerably improved by reducing the time taken to restore the system to the working state when faults occur. Fault identification can be a significant proportion of the time taken in the repair process. Having diagnosed the problem the restoration of the system back to its fully functioning condition can then take place. This paper expands the capability of previous approaches to fault detection and identification using fault trees for application to dynamically changing systems. The technique has two phases. The first phase is modelling and preparation carried out offline. This gathers information on the effects that sub-system failure will have on the system performance. Causes of the sub-system failures are developed in the form of fault trees. The second phase is application. Sensors are installed on the system to provide information about current system performance from which the potential causes can be deduced. A simple system example is used to demonstrate the features of the method. To illustrate the potential for the method to deal with additional system complexity and redundancy, a section from an aircraft fuel system is used. A discussion of the results is provided. 相似文献
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Nasir Mahmood Yaser Hafeez Khalid Iqbal Shariq Hussain Muhammad Aqib Muhammad Jamal Oh-Young Song 《计算机、材料和连续体(英文)》2021,69(1):873-893
Despite advances in technological complexity and efforts, software repository maintenance requires reusing the data to reduce the effort and complexity. However, increasing ambiguity, irrelevance, and bugs while extracting similar data during software development generate a large amount of data from those data that reside in repositories. Thus, there is a need for a repository mining technique for relevant and bug-free data prediction. This paper proposes a fault prediction approach using a data-mining technique to find good predictors for high-quality software. To predict errors in mining data, the Apriori algorithm was used to discover association rules by fixing confidence at more than 40% and support at least 30%. The pruning strategy was adopted based on evaluation measures. Next, the rules were extracted from three projects of different domains; the extracted rules were then combined to obtain the most popular rules based on the evaluation measure values. To evaluate the proposed approach, we conducted an experimental study to compare the proposed rules with existing ones using four different industrial projects. The evaluation showed that the results of our proposal are promising. Practitioners and developers can utilize these rules for defect prediction during early software development. 相似文献
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针对恶劣工况环境下复杂矿用设备状态监测与预测性维护困难等问题,结合状态监测、故障预警和预测维护等多种综合建模与分析预测技术,提出了一种基于数字孪生的预测性维护系统。首先,介绍了复杂矿用设备数字孪生体的设计流程与构建原理,并在搭建数字孪生体的过程中实现了预测性维护系统的功能;然后,研究了基于LabVIEW、MySQL和Unity3D的状态数据获取方法,利用Unity3D开发引擎搭建了三维可视化复杂矿用设备状态监测平台,并通过虚拟空间可视化展示设备当前状态;最后,分析了优化BP(back propagation,反向传播)神经网络在复杂矿用设备故障预警中的适用性,同时利用MATLAB软件建立了复杂矿用设备关键零部件的预测性维护模型,并将预警结果通过MySQL数据库传输至Unity3D开发引擎,以驱动和部署预设维护流程,实现设备状态实时监测下的关键零部件故障预警。根据采煤机液压系统的实际维修流程,制定了混合现实(mixed reality, MR)预测性维护策略,并以采煤机摇臂部液压柱塞泵为实验对象开展有效性验证。结果表明,所构建的预测性维护系统的故障预测准确率高于90%,且故障预警结果可驱动HoloLens眼镜实现虚拟指导的维修交互,验证了该系统预测性维护功能的有效性。研究结果可为复杂矿用设备的预测性维护提供新思路。 相似文献
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无人机产业近年来发展迅猛,在军用和民用方面都拥有广泛的应用前景。无人机的航迹记录在其航行过程中发挥着重要作用,无人机的航迹预测也成为当前世界研究的热点,使用神经网络进行航迹预测更可以充分发挥其优势。首先对国内外学者关于航迹预测的文献进行了梳理,根据航迹预测的原理对目前飞行器航迹预测算法进行了总结和分类,针对利用神经网络模型预测无人机航迹并逐步改进模型以提高预测精度的问题进行了研究。接着对于传统神经网络模型预测精度不够高的问题,提出一种带误差修正的嵌套长短期记忆 (ENLSTM) 神经网络预测模型。ENLSTM 在嵌套长短期记忆网络模型的基础上引入了误差修正项,从而使得预测精度更高。最后使用 BP、RNN、LSTM 和 ENLSTM 四种神经网络模型分别对无人机的真实航迹数据和模拟航迹数据进行仿真实验,得出结论:循环神经网络相对 BP 神经网络在无人机航迹的预测上更具有优势,基于基础循环神经网络的逐步改进提升了模型的预测能力,ENLSTM 模型对于无人机的航迹预测具有更好的效果。 相似文献
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曲轴轴承早期磨损故障特征微弱且呈现非平稳循环特征,提出一种非平稳循环特征极坐标增强方法。利用连续小波变换对发动机振动信号进行处理,然后根据发动机工作过程与配气相位的关系对于每一工作循环数据进行等角度采样,将信号特征由直角坐标系映射到极坐标系并进行同步增强,并利用模糊C均值聚类对故障特征参数进行分类识别。仿真信号的分析对比显示了该方法能够削弱噪声干扰,突出信号特征。运用此方法对某型发动机曲轴轴承磨损信号进行分析,有效地提取了曲轴轴承磨损特征信息,准确识别了曲轴轴承不同磨损故障。 相似文献
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设计应用无线数传技术实现数据传输的组合式成型生产线的监控系统,采用分布式结构建立统一协议模型实现不同终端设备的数据联网传输.研究符合组合式成型生产线的无线通讯技术,可以满足移动成型鼓工作时对电压、电流、运行速度、液压系统压力、故障状态等电气参数的网络传输.该技术已得到成功的实验测试并在其它行业得以应用,能有效提高系统监控与管理的效率. 相似文献
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