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基于双层自适应集成残差主成分分析的复杂非线性过程监测
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作者 唐徐佳 卢伟鹏 颜学峰 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期88-96,共9页
多元统计监测方法常使用正常数据选取特征,而现实过程中,不同的故障将影响不同的特征,并且这些特征可能随着时间和控制系统的作用而变化。当故障发生并随时间变化时,要想获得更好的故障检测能力,就需要聚集有效的故障敏感特征。本文提... 多元统计监测方法常使用正常数据选取特征,而现实过程中,不同的故障将影响不同的特征,并且这些特征可能随着时间和控制系统的作用而变化。当故障发生并随时间变化时,要想获得更好的故障检测能力,就需要聚集有效的故障敏感特征。本文提出了一种双层自适应集成残差主成分分析(AERPCA)模型,其子模型包含不同的特征,并突出地呈现一个或多个相关故障。首先,根据正常数据计算主成分分析(PCA)特征,利用不同特征构建线性子模型和相应的残差空间。考虑到残差空间的非线性特性及有效特征更为分散,采用核PCA(KPCA)提取不同的特征并组成同一残差空间下不同KPCA子模型。然后,利用贝叶斯方法获取集成KPCA子模型,完成各残差空间的划分和集成。最后,在主空间中获得多个线性子模型以及在残差空间中获得多个集成的非线性子模型后,利用滑动窗口确定当前时刻监控效果最好的模型。采用田纳西-伊士曼过程验证了AERPCA的有效性。 展开更多
关键词 集成学习 自适应过程 核主成分分析 非线性过程监测 故障诊断
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基于非线性动力学采空区稳定性监测分析 被引量:8
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作者 来兴平 石平五 +1 位作者 伍永平 蔡美峰 《西安科技学院学报》 北大核心 2002年第1期1-4,共4页
阐述了非线性监测监控技术在岩石地下工程围岩稳定性分析与预报的重要地位和声发射技术在该领域的应用特征 ,并将其用于实际工程中 ,通过实时监测监控 ,分析了岩石声发射的时间序列与破坏过程 ,对安全施工与生产有实时性、可靠性和可预... 阐述了非线性监测监控技术在岩石地下工程围岩稳定性分析与预报的重要地位和声发射技术在该领域的应用特征 ,并将其用于实际工程中 ,通过实时监测监控 ,分析了岩石声发射的时间序列与破坏过程 ,对安全施工与生产有实时性、可靠性和可预测性。 展开更多
关键词 非线性动力学 采空区 稳定性 非线性监测监控 声发射 岩土工程 岩体力学 时间序列 破坏过程
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多维光纤通信系统性能监测技术 被引量:11
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作者 蒋林 易安林 +3 位作者 盘艳 闫连山 潘炜 罗斌 《应用科学学报》 CAS CSCD 北大核心 2020年第4期542-558,共17页
目前光纤通信系统正朝着超高速、大容量、动态化方向快速发展,新的维度和复用方式以及更加复杂的体系架构对光纤传送网安全可靠运行提出了巨大的挑战.多维光纤通信系统中的性能监测技术能对系统所受损伤进行监测与预警,为自适应补偿、... 目前光纤通信系统正朝着超高速、大容量、动态化方向快速发展,新的维度和复用方式以及更加复杂的体系架构对光纤传送网安全可靠运行提出了巨大的挑战.多维光纤通信系统中的性能监测技术能对系统所受损伤进行监测与预警,为自适应补偿、传输质量评估和网络资源优化等提供信息来源和管理依据,对提升光纤传送网运行和管理水平具有重要的科学意义和社会意义.该文首先重点介绍色散参量监测、非线性参量监测、调制格式参量监测等多个参量监测的研究现状,随后讨论并分析了多维光纤通信系统性能监测技术的发展趋势.未来性能监测技术将朝着精细化、一体化、智能化、多参量同步监测等方向发展. 展开更多
关键词 光性能监测 色散监测 非线性监测 调制格式监测
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非X线监测下V型针闭合髓内固定治疗胫骨骨折
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作者 侯建平 《中国乡村医药》 2002年第2期18-18,共1页
胫骨骨折的手术治疗方法很多.尤其近年来在C型臂X线监测下用Ender钉及矩形钉治疗胫骨骨折取得了很好的疗效,但因广大基层医院大多无此设备,很大程度上限制了Ender钉和矩形钉的应用.自1999年以来,我院用V型针对16例胫骨骨折患者采用非X... 胫骨骨折的手术治疗方法很多.尤其近年来在C型臂X线监测下用Ender钉及矩形钉治疗胫骨骨折取得了很好的疗效,但因广大基层医院大多无此设备,很大程度上限制了Ender钉和矩形钉的应用.自1999年以来,我院用V型针对16例胫骨骨折患者采用非X线监测下V型针闭合髓内固定术,取得了满意的疗效,现总结报告如下. 展开更多
关键词 胫骨骨折 非线性监测 V型针 闭合髓内固定术 骨折治疗
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基于核正交流形角不相似度的非线性动态过程监测方法
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作者 卢春红 文万志 《控制与决策》 EI CSCD 北大核心 2018年第6期1141-1146,共6页
针对过程的非线性和动态特性,提出一种基于核正交流形角不相似度的监测方法.利用两个流形子空间正交向量求取内积矩阵的奇异值,构建基于核正交流形角的不相似度指标,量化评估标准集和测试集的流形子空间的统计量关系.首先,在多流形投影... 针对过程的非线性和动态特性,提出一种基于核正交流形角不相似度的监测方法.利用两个流形子空间正交向量求取内积矩阵的奇异值,构建基于核正交流形角的不相似度指标,量化评估标准集和测试集的流形子空间的统计量关系.首先,在多流形投影方法的基础上,利用非线性函数将原始过程数据投影到特征空间;其次,引入Gram-Schmidt方法正交化投影向量,形成流形子空间的基向量;再次,对两个流形子空间的内积进行特征值分解,获得核正交流形角,构建不相似度监测模型,该监测指标融合角度和距离度量,能够更好地触发故障警报;最后,通过在TE过程上的仿真实验验证了所提出算法的优越性. 展开更多
关键词 非线性动态过程监测 核正交流形投影 正交向量 不相似度指标 故障检测
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基于高效核偏最小二乘的质量相关故障检测 被引量:2
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作者 孔祥玉 周红平 +2 位作者 罗家宇 安秋生 陈雅琳 《控制理论与应用》 EI CAS CSCD 北大核心 2023年第4期683-692,共10页
核偏最小二乘(KPLS)是一种多元统计方法,广泛应用于过程监控,然而,KPLS采用斜交分解,导致质量相关空间存在冗余信息易引发误报警.因此,本文提出了高效核偏最小二乘(EKPLS)模型,所提方法通过奇异值分解(SVD)将核矩阵正交分解为质量相关... 核偏最小二乘(KPLS)是一种多元统计方法,广泛应用于过程监控,然而,KPLS采用斜交分解,导致质量相关空间存在冗余信息易引发误报警.因此,本文提出了高效核偏最小二乘(EKPLS)模型,所提方法通过奇异值分解(SVD)将核矩阵正交分解为质量相关空间和质量无关空间,有效降低质量相关空间中的冗余信息,并采用主成分分析(PCA)按方差大小将质量相关空间分解为质量主空间和质量次空间.此外,为进一步降低由质量无关故障引发的误报警,提出基于质量估计的正交信号修正(OSC)预处理方法,并结合EKPLS模型提出了OSC-EKPLS算法.OSCEKPLS通过质量估计值对被测数据进行OSC预处理,降低了计算复杂度和误报率.最后,通过数值仿真和田纳西–伊斯曼过程验证了OSC-EKPLS具有良好的故障检测性和更低的误报率. 展开更多
关键词 故障检测 正交信号修正 质量相关 核偏最小二乘 非线性过程监测 误报率
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低信噪比情况下几种信号探测技术的对比研究
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作者 张小飞 唱亮 宋柯平 《中国无线电》 2010年第6期52-55,共4页
针对认知无线电频谱空穴探测技术中低信噪比信号探测的三种算法,从检测性能、适用范围、计算复杂度和信号参数估计等几方面进行了分类对比及仿真研究。
关键词 能量检测 非线性变换监测 循环谱检测
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Effect of Temperature Variation on the Separation of Sesamin and Sesamolin by Simulated Moving Bed 被引量:1
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作者 Ming-Tsai Llang Ru-Chien Liang +2 位作者 Ling-Ya Wang Hung-En Yen Kuo-Tong Lee 《Journal of Chemistry and Chemical Engineering》 2011年第6期479-486,共8页
In this work, sesamin and sesamolin is separated and purified by SMB (simulated moving bed) chromatography. Purity of sesamin and sesamolin can reach 99.2% and 99.9 %, and they can be recovered by 99.9% and 99.4%, r... In this work, sesamin and sesamolin is separated and purified by SMB (simulated moving bed) chromatography. Purity of sesamin and sesamolin can reach 99.2% and 99.9 %, and they can be recovered by 99.9% and 99.4%, respectively. Concentrations of the extract and raffinate was monitored and periodical change of the concentration was observed on experiment. Effects of non-linear adsorption, dead volume, and temperature on the separation are reviewed by the triangle theory to explain the periodical change of concentration. It is found that dead volume has little effect, and temperature fluctuation significantly affects thc separation by SMB. The temperature seriously affects the robust operation of SMB due to the change of Henry's constant, which will change the selectivity and restrain the productivity. Although the productivity in this study is only 0.0416 g/L-hr, the cost of the stationary phase used in this study is much lower than that of packed in analytical column. By using this stationary phase, the authors are still able to separate the mixture of sesamin and sesmolin. This will economically attract attention for the application of SMB to purify bioactive compounds on developing botanical drugs. 展开更多
关键词 Simulated moving bed SESAMIN SESAMOLIN chromatography.
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Hellinger distance based probability distribution approach to performance monitoring of nonlinear control systems 被引量:2
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作者 李晨 黄彪 钱锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1945-1950,共6页
Control performance monitoring has attracted great attention in both academia and industry over the past two decades. However, most research efforts have been devoted to the performance monitoring of linear control sy... Control performance monitoring has attracted great attention in both academia and industry over the past two decades. However, most research efforts have been devoted to the performance monitoring of linear control systems, without considering the pervasive nonlinearities(e.g. valve stiction) present in most industrial control systems. In this work, a novel probability distribution distance based index is proposed to monitor the performance of non-linear control systems. The proposed method uses Hellinger distance to evaluate change of control system performance. Several simulation examples are given to illustrate the effectiveness of the proposed method. 展开更多
关键词 Control performance monitoring Kernel density estimation Hellinger distance Nonlinear system
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Software Package Evaluation for Lyapunov Exponent and Others Features of Signals Evaluating Condition Monitoring Performance of Nonlinear Dynamic Systems
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作者 Julio Cesar Gomez-Mancilla Luis Manuel Palacios-Pineda Valeriy Nosov 《Journal of Energy and Power Engineering》 2015年第5期443-451,共9页
Efficient use of industrial equipment, increase its availability, safety and economic issues spur strong research on maintenance programs based on their operating conditions. Machines normally operate in a linear rang... Efficient use of industrial equipment, increase its availability, safety and economic issues spur strong research on maintenance programs based on their operating conditions. Machines normally operate in a linear range, but when malfunctions occur, nonlinear behavior might set in. By studying and comparing five nonlinear features, which listed in decreasing order by their damage detection capability are: LLE (largest Lyapunov exponent), embedded dimension, Kappa determinism, time delay and cross error values; i.e., LLE performs best. Using somewhat similar ideas from Chaos control, i.e., vary the "mass imbalance" forcing parameters, we aim to stabilize the Lorenz equation. Quite interestingly, for certain imbalance excitation values, the system is stabilized. The previous even when paradigmatically chaotic parameters for Lorenz system are used (plus our forcing terms). This quasi-control approach is validated studying signals obtained from the previously mentioned lab test. Finally, it is concluded that analyzing and comparing nonlinear features extracted from baseline vs. malfunction condition (test acquired), one might increase the efficiency and the performance of machine condition monitoring. 展开更多
关键词 Modified Lorenz equation largest Lyapunov exponent nonlinear features chaos control test validation.
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OBSERVATION OF NONLINEAR VERTICUM-TYPE SYSTEMS APPLIED TO ECOLOGICAL MONITORING
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作者 S. MOLNAR M. GAMEZ LOPEZ 《International Journal of Biomathematics》 2012年第6期61-75,共15页
In this paper the concept of a nonlinear verticumtype observation system is introduced. These systems are composed from several "subsystems" connected sequentially in a particular way: a part of the state variables... In this paper the concept of a nonlinear verticumtype observation system is introduced. These systems are composed from several "subsystems" connected sequentially in a particular way: a part of the state variables of each "subsystem" also appears in the next "subsystem" as an "exogenous variable" which can also be interpreted as a con trol generated by an "exosystem". Therefore these "subsystems" are not observation systems, but formally can be considered as controlobservation systems. The problem of observability of such systems can be reduced to rank conditions on the "subsystems". Indeed, under the condition of Lyapunov stability of an equilibrium of the "large", verticumtype system, it is shown that the Kalman rank condition on the linearization of the "subsystems" implies the observability of the original, nonlinear verticumtype system. For an illustration of the above linearization result, a stagestructured fishery model with reserve area is considered. Observability for this system is obtained by applying the above linearization and decomposition approach. Furthermore, it is also shown that, applying an appropriate observer design method to each subsystem, from the observa tion of the biomass densities of the adult (harvested) stage, in both areas, the biomass densities of the prerecruit stage can be efficiently estimated. 展开更多
关键词 Verticum-type system nonlinear system OBSERVABILITY observer design fishery with reserve area.
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