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Chaos, Fractal and Recurrence Quantification Analysis of Surface Electromyography in Muscular Dystrophy 被引量:1
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作者 Elio Conte Ken Ware +5 位作者 Riccardo Marvulli Giancarlo Ianieri Marisa Megna Sergio Conte Leonardo Mendolicchio Enrico Pierangeli 《World Journal of Neuroscience》 2015年第4期205-257,共53页
We analyze muscular dystrophy recorded by sEMG and use standard methodologies and nonlinear chaotic methods here including the RQA. We reach sufficient evidence that the sEMG signal contains a large chaotic component.... We analyze muscular dystrophy recorded by sEMG and use standard methodologies and nonlinear chaotic methods here including the RQA. We reach sufficient evidence that the sEMG signal contains a large chaotic component. We have estimated the correlation dimension (fractal measure), the largest Lyapunov exponent, the LZ complexity and the %Rec and %Det of the RQA demonstrating that such indexes are able to detect the presence of repetitive hidden patterns in sEMG which, in turn, senses the level of MU synchronization within the muscle. The results give also an interesting methodological indication in the sense that it evidences the manner in which nonlinear methods and RQA must be arranged and applied in clinical routine in order to obtain results of clinical interest. We have studied the muscular dystrophy and evidence that the continuous regime of chaotic transitions that we have in muscular mechanisms may benefit in this pathology by the use of the NPT treatment that we have considered in detail in our previous publications. 展开更多
关键词 CHAOS analysis Correlation Dimension LZ Complexity recurrence quantification analysis MUSCULAR DYSTROPHY CHAOS and FRACTAL Estimation by Surface ELECTROMYOGRAPHY
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Predicting the subcellular location of apoptosis proteins based on recurrence quantification analysis and the Hilbert Huang transform
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作者 韩国胜 喻祖国 Anh Vo 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期140-149,共10页
Apoptosis proteins play an important role in the development and homeostasis of an organism. The elucidation of the subcellular locations and functions of these proteins is helpful for understanding the mechanism of p... Apoptosis proteins play an important role in the development and homeostasis of an organism. The elucidation of the subcellular locations and functions of these proteins is helpful for understanding the mechanism of programmed cell death. In this paper, the recurrent quantification analysis, Hilbert-Huang transform methods, the maximum relevance and minimum redundancy method and support vector machine are used to predict the subcellular location of apoptosis proteins. The validation of the jackknife test suggests that the proposed method can improve the prediction accuracy of the subcellular location of apoptosis proteins and its application may be promising in other fields. 展开更多
关键词 apoptosis proteins subcellular location recurrent quantification analysis Hilbert-Huangtransform
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Recurrence quantification analysis on pulse morphological changes in patients with coronary heart disease 被引量:4
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作者 Rui Guo Yiqin Wang +1 位作者 Jianjun Yan Hanxia Yan 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第4期571-577,共7页
OBJECTIVE: To show that the pulse diagnosis used in Traditional Chinese Medicine, combined with nonlinear dynamic analysis, can help identify car- diovascular diseases. METHODS: Recurrence quantification analysis (... OBJECTIVE: To show that the pulse diagnosis used in Traditional Chinese Medicine, combined with nonlinear dynamic analysis, can help identify car- diovascular diseases. METHODS: Recurrence quantification analysis (RQA) was used to study pulse morphological changes in 37 inpatients with coronary heart dis- ease (CHD) and 37 normal subjects (controls). An in- dependent sample t-test detected significant differ- ences in RQA measures of their pulses. A support vector machine (SVM) classified the groups accord- ing to their RQA measures. Classic time-domain pa- rameters were used for comparison. RESULTS: RQA measures can be divided into two groups. One group of measures [ecurrence rate(RR), determinism (DEL), average diagonal line length (L), maximum length of diagonal structures (Lmax), Shannon entropy of the frequency distribu- tion of diagonal line lengths (ENTR), laminarity (LAM), average length of vertical structures (TT), maximum length of vertical structures (Vmax)] showed significantly higher values for patients with CHD than for normal subjects (P〈0.0S). The other measures (RR_std, L_std, Lmaxstd, TT_std, Vmax_std) showed significantly lower values for the CHD group than for normal subjects (P〈0.05). SVM classification accuracy was higher with RQA measures: With RQA (16 parameters) accuracy was at 88.21%, and with RQA(12 parameters) accuracy was at 84.11%. In contrast, with classic time-do- main (15 parameters) accuracy was 75.73%, and with time-domain (7 parameters) accuracy was 74.7O%. CONCLUSION: Nonlinear dynamic methods such as RQA can be used to study functional and struc- tural changes in the pulse noninvasively. Pulse sig- nals of individuals with CHD have greater regulari- ty, determinism, and stability than normal subjects, and their pulse morphology displays less variabili- ty. RQA can distinguish the CHD pulse from the healthy pulse with an accuracy of 88.21%, thereby providing an early diagnosis of cardiovascular dis- eases such as CHD. 展开更多
关键词 Pulse-taking Cardiovascular diseases recurrence quantification analysis
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Analysis of Key Features of Non-Linear Behavior Using Recurrence Plots. Case Study: Urban Pollution at Mexico City
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作者 Marco A. Aceves-Fernandez Jesus Carlos Pedraza-Ortega +3 位作者 Artemio Sotomayor-Olmedo Juan M. Ramos-Arreguín Jose Emilio Vargas-Soto Saul Tovar-Arriaga 《Journal of Environmental Protection》 2012年第9期1147-1160,共14页
The use of Recurrence plots have been extensively used in various fields. In this work, Recurrence Plots (RPs) investigates the changes in the non-linear behaviour of urban air pollution using large datasets of raw da... The use of Recurrence plots have been extensively used in various fields. In this work, Recurrence Plots (RPs) investigates the changes in the non-linear behaviour of urban air pollution using large datasets of raw data (hourly). This analysis has not been used before to extract information from large datasets for this type non-linear problem. Two different approaches have been used to tackle this problem. The first approach is to show results according to monitoring network. The second approach is to show the results by particle type. This analysis shows the feasibility of using Recurrence Analysis for pollution monitoring and control. 展开更多
关键词 recurrence plot AIR Quality AIR POLLUTION Modelling ATMOSPHERIC POLLUTION recurrence quantification analysis
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Comparison study of typical algorithms for reconstructing time series from the recurrence plot of dynamical systems 被引量:1
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作者 刘杰 石书婷 赵军产 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期131-137,共7页
The three most widely used methods for reconstructing the underlying time series via the recurrence plots (RPs) of a dynamical system are compared with each other in this paper. We aim to reconstruct a toy series, a... The three most widely used methods for reconstructing the underlying time series via the recurrence plots (RPs) of a dynamical system are compared with each other in this paper. We aim to reconstruct a toy series, a periodical series, a random series, and a chaotic series to compare the effectiveness of the most widely used typical methods in terms of signal correlation analysis. The application of the most effective algorithm to the typical chaotic Lorenz system verifies the correctness of such an effective algorithm. It is verified that, based on the unthresholded RPs, one can reconstruct the original attractor by choosing different RP thresholds based on the Hirata algorithm. It is shown that, in real applications, it is possible to reconstruct the underlying dynamics by using quite little information from observations of real dynamical systems. Moreover, rules of the threshold chosen in the algorithm are also suggested. 展开更多
关键词 recurrence plot chaotic system time series analysis correlation analysis
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Characterization of various structures in gas-solid fluidized beds by recurrence quantification analysis 被引量:10
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作者 M.Tahmasebpour R.Zarghami +1 位作者 R.Sotudeh-Gharebagh N.Mostoufi 《Particuology》 SCIE EI CAS CSCD 2013年第6期647-656,共10页
Gas-solid fluidized beds are widely considered as nonlinear and chaotic dynamic systems. Pressure fluc- tuations were measured in a fluidized bed of 0.15 m in diameter and were analyzed using multiple approaches: dis... Gas-solid fluidized beds are widely considered as nonlinear and chaotic dynamic systems. Pressure fluc- tuations were measured in a fluidized bed of 0.15 m in diameter and were analyzed using multiple approaches: discrete Fourier transform (DFT), discrete wavelet transform (DWT), and nonlinear recur- rence quantification analysis (RQA). Three different methods proposed that the complex dynamics of a fluidized bed system can be presented as macro, meso and micro structures. It was found from DFT and DWT that a minimum in wide band energy with an increase in the velocity corresponds to the transition between macro structures and finer structures of the fluidization system. Corresponding transition veloc- ity occurs at gas velocities of 0.3, 0.5 and 0.6 m]s for sands with mean diameters of 150, 280 and 490/~m, respectively. DFT, DWT, and RQA could determine frequency range of0-3.125 Hz for macro, 3. ! 25-50 Hz for meso, and 50-200 Hz for micro structures. The RQA showed that the micro structures have the least periodicity and consequently their determinism and laminarity are the lowest. The results show that a combination of DFT, DWT, and RQA can be used as an effective approach to characterize multi-scale flow behavior in gas-solid fluidized beds. 展开更多
关键词 Fluidization recurrence quantification analysis Multi-scale Pressure fluctuations Chaos Hydrodynamics
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Automatic Assessment of Expanded Disability Status Scale (EDSS) in Multiple Sclerosis Using a Decision Tree
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作者 Hua Cao Olivier Agnani +2 位作者 Laurent Peyrodie Samuel Boudet Cecile Donze 《Engineering(科研)》 2013年第10期566-569,共4页
The expanded disability status scale (EDSS) is frequently used to classify the patients with multiple sclerosis (MS). We presented in this paper a novel method to automatically assess the EDSS score from posturologic ... The expanded disability status scale (EDSS) is frequently used to classify the patients with multiple sclerosis (MS). We presented in this paper a novel method to automatically assess the EDSS score from posturologic data (center of pres-sure signals) using a decision tree. Two groups of participants (one for learning and the other for test) with EDSS rang-ing from 0 to 4.5 performed our balance experiment with eyes closed. Two linear measures (the length and the surface) and twelve non-linear measures (the recurrence rate, the Shannon entropy, the averaged diagonal line length and the trapping time for the position, the instantaneous velocity and the instantaneous acceleration of the center of pressure respectively) were calculated for all the participants. Several decision trees were constructed with learning data and tested with test data. By comparing clinical and estimated EDSS scores in the test group, we selected one decision tree with five measures which revealed a 75% of agreement. The results have signified that our tree model is able to auto-matically assess the EDSS scores and that it is possible to distinguish the EDSS scores by using linear and non-linear postural sway measures. 展开更多
关键词 Multiple Sclerosis (MS) Expanded Disability Status Scale (EDSS) Center of Pressure (COP) recurrence quantification analysis (RQA) Decision Tree
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胎心率多尺度递归定量分析在胎儿状态诊断中的预测价值
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作者 白雪利 张曙萱 《中国现代医生》 2025年第35期33-36,41,共5页
目的研究胎心率(fetal heart rate,FHR)多尺度递归定量分析(recurrence quantification analysis,RQA)指标与胎儿状态异常的相关性。方法采用捷克技术大学-布尔诺大学医院公开数据库共获取552例FHR信号。其中,39例脐动脉pH<7.15的FH... 目的研究胎心率(fetal heart rate,FHR)多尺度递归定量分析(recurrence quantification analysis,RQA)指标与胎儿状态异常的相关性。方法采用捷克技术大学-布尔诺大学医院公开数据库共获取552例FHR信号。其中,39例脐动脉pH<7.15的FHR信号为研究组,513例脐动脉pH>7.15的FHR信号为对照组。基于自适应噪声完备集合经验模态分解算法将两组FHR信号进行多尺度分解重构,对分解结果进行RQA,比较不同组别RQA指标水平。采用多因素Logistic回归分析发生胎儿状态异常的影响因素,采用受试者操作特征曲线(receiver operating characteristic curve,ROC曲线)分析RQA指标对胎儿状态异常的预测价值。结果两组的多尺度递归图具有不同的纹理结构。与对照组相比,研究组RQA指标的递归率(recurrence rate,RR)和捕获时间(trapping time,TT)水平升高,差异有统计学意义(P<0.05)。RR和TT水平升高是发生胎儿状态异常的危险因素(P<0.05)。RR和TT独立预测胎儿状态异常的ROC曲线下面积(area under the curve,AUC)分别为0.812和0.793,而二者联合预测胎儿状态异常的AUC为0.901,显著高于二者单独预测。结论FHR信号多尺度RQA指标RR和TT对胎儿状态异常有一定预测价值。 展开更多
关键词 胎心率 多尺度 递归定量分析 诊断价值
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基于图像纹理分析的递归图特征量化方法研究
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作者 李燕 《统计与决策》 北大核心 2025年第18期18-23,共6页
基于递归图理论的非线性时间序列分析方法越来越受到各领域研究者的重视,已经被成功应用于多个领域。但传统递归图使用Heavyside阶跃函数来判断相空间中状态点的递归行为,这存在两个问题:(1)Heavyside阶跃函数会产生刚性边界问题,造成... 基于递归图理论的非线性时间序列分析方法越来越受到各领域研究者的重视,已经被成功应用于多个领域。但传统递归图使用Heavyside阶跃函数来判断相空间中状态点的递归行为,这存在两个问题:(1)Heavyside阶跃函数会产生刚性边界问题,造成信息丢失;(2)临界距离的选取非常关键,选取不恰当会造成低维动力学错误,但目前对该参数的选取并没有统一的方法。针对上述问题,文章提出如下改进方法:(1)在判断状态相点递归性时使用Gaussian函数代替Heavyside阶跃函数,解决Heaviside阶跃函数所造成的递归分析结果的刚性边界和二元值问题;(2)使用局部二值模型(LBP)和纹理相似性度量Earth Mover’s Distance模型(EMD),就复杂系统动力学特征分析提出了对递归图进行纹理分析的新思路,并在此基础上构建了度量复杂系统动力学特征相似度的方法体系。研究结果显示,所构建的方法能够灵敏且准确地识别出洛伦兹系统动力学特征的突变点,表明该方法能够有效度量复杂系统动力学特征的相似度。 展开更多
关键词 Gaussian函数递归图 动力学特征 复杂系统 纹理分析
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基于RQA与DAGSVM的电能质量扰动识别方法
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作者 陈武 钟建伟 +1 位作者 杨永超 梁会军 《计算机仿真》 2025年第1期52-56,共5页
针对电能质量扰动(power quality disturbance, PQD)随机多变导致的特征交叉及分类性能不足的问题,提出了一种递归定量分析(recurrence quantification analysis, RQA)与有向无环图支持向量机(directed acyclic graph support vector ma... 针对电能质量扰动(power quality disturbance, PQD)随机多变导致的特征交叉及分类性能不足的问题,提出了一种递归定量分析(recurrence quantification analysis, RQA)与有向无环图支持向量机(directed acyclic graph support vector machine, DAGSVM)的PQD分类新方法。首先利用基于复杂网络理论的递归定量分析法定量刻画电能质量扰动的递归图,并构造特征矩阵;其次通过DAGSVM构建PQD分类模型;最后采用基于发现学习的教与学优化算法优化PQD分类器的惩罚系数和核函数参数从而提升PQD分类器性能。结果表明,上述方法对PQD具有较高的识别准确率和良好的抗噪性。 展开更多
关键词 电能质量扰动信号 分类 教与学优化算法 递归定量分析
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基于RQA与GG聚类的滚动轴承故障识别 被引量:30
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作者 张淑清 包红燕 +2 位作者 李盼 李新新 姜万录 《中国机械工程》 EI CAS CSCD 北大核心 2015年第10期1385-1390,共6页
提出递归定量分析与GG聚类相结合的滚动轴承故障识别方法。利用能够表征信号发散程度的RQA参数——确定率和分层率组成轴承故障识别的特征向量,结合GG模糊聚类实现滚动轴承故障模式识别。对实际故障数据进行分析,结果表明,该方法不仅能... 提出递归定量分析与GG聚类相结合的滚动轴承故障识别方法。利用能够表征信号发散程度的RQA参数——确定率和分层率组成轴承故障识别的特征向量,结合GG模糊聚类实现滚动轴承故障模式识别。对实际故障数据进行分析,结果表明,该方法不仅能够识别滚动轴承的不同程度损伤,而且能够实现不同部位的轴承故障诊断。研究结果为滚动轴承故障识别提供了一种高效、直观的新方法。 展开更多
关键词 故障诊断 递归图 递归定量分析 GG模糊聚类
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水平气液两相流流型图像信息递归特征分析 被引量:13
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作者 李洪伟 周云龙 +2 位作者 宋倩 孙斌 杨悦 《化工学报》 EI CAS CSCD 北大核心 2010年第6期1431-1436,共6页
On the streaming video of all typical flow pattern filmings on the experiment system by the high-speed video camera,the information of a single-frame was extracted and made into time-series.The series was analyzed wit... On the streaming video of all typical flow pattern filmings on the experiment system by the high-speed video camera,the information of a single-frame was extracted and made into time-series.The series was analyzed with the non-linear chaotic recurrence plot(RP),less used in the last years.It was combined with the average diagonal length and Shannon entropy of recursive features changed after the increase of gas superficial velocity.The results showed that the information entropy of flow image combined with RP could well characterize the evaluated tract of gas-liquid two-phase flow patterns.At the same time,the information well characterized the volume fraction of all kinds of gas-liquid two-phase flow patterns.The average diagonal length and recursive Shannon entropy of recursive features all increased first and then decreased with the increase of gas superficial velocity,and it reflected the transition of the mechanisms of five typical flow patterns from the recursive characteristics. 展开更多
关键词 气液两相流 流动图像 信息熵序列 递归图 递归特征量
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基于超声背散射信号递归分析的金属材料微缺陷识别 被引量:11
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作者 杨辰龙 冯玮 +2 位作者 边成亮 周晓军 柴景云 《光学精密工程》 EI CAS CSCD 北大核心 2019年第4期932-944,共13页
为了能有效识别金属材料超声检测信号中的微小缺陷回波,使用递归分析方法对检测信号进行分析。通过对超声波背散射信号进行建模,说明其组成要素。在超声检测信号中,缺陷回波信号会对系统的递归特性产生影响。使用递归分析对含0.8mm平底... 为了能有效识别金属材料超声检测信号中的微小缺陷回波,使用递归分析方法对检测信号进行分析。通过对超声波背散射信号进行建模,说明其组成要素。在超声检测信号中,缺陷回波信号会对系统的递归特性产生影响。使用递归分析对含0.8mm平底孔人工模拟缺陷的直径为120mm低碳钢棒材试块实验采集的背散射信号和无缺陷背散射信号进行了研究。截取试块检测信号中的背散射信号部分,通过合理的参数选择对其进行递归分析并绘制递归图。通过与实验采集的无缺陷信号的递归图进行对比,发现缺陷信号会在递归图中产生明显的白色交叉条纹带。使用递归定量分析进一步研究了含缺陷背散射信号的递归特征量,结果表明捕获时间(TT)、确定率(DET)与递归熵(ENTR)这三项特征量对缺陷信号比较敏感,在缺陷位置处均会出现明显的峰值。 展开更多
关键词 金属材料 背散射信号 递归分析 递归图 递归定量分析
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基于递归定量分析与高斯混合模型的齿轮故障识别 被引量:14
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作者 肖涵 李友荣 吕勇 《振动工程学报》 EI CSCD 北大核心 2011年第1期84-88,共5页
针对递归图只能对信号进行定性分析,不利于其深入应用的缺点,应用递归定量分析方法对各种故障模式振动信号进行定量分析。采用确定率和层流率组成齿轮故障识别的特征向量,并结合高斯混合模型实现齿轮故障模式识别。以齿轮故障实验台上... 针对递归图只能对信号进行定性分析,不利于其深入应用的缺点,应用递归定量分析方法对各种故障模式振动信号进行定量分析。采用确定率和层流率组成齿轮故障识别的特征向量,并结合高斯混合模型实现齿轮故障模式识别。以齿轮故障实验台上所测取的实验数据为对象,分别采用Re-substitution检验法,Jackknife检验法和Inde-pendent dataset检验法对提出的方法和RBF人工神经网络分类算法进行检验。结果表明,递归定量分析与高斯混合模型相结合应用于齿轮故障模式识别具有更高的识别率。 展开更多
关键词 递归图 递归定量分析 高斯混合模型 故障识别
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流化床内生物质石英砂双组分混合流动混沌递归分析 被引量:9
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作者 王肖祎 仲兆平 王春华 《化工学报》 EI CAS CSCD 北大核心 2014年第3期813-819,共7页
采用递归分析方法对流化床内的压力脉动信号进行分析,研究了不同工况下石英砂与柱形生物质颗粒混合双组分颗粒的流动特性。柱形生物质颗粒尺寸为10 mm×10 mm(直径×长),石英砂粒径为0.8 mm。在鼓泡床阶段,随着生物质含量的增加... 采用递归分析方法对流化床内的压力脉动信号进行分析,研究了不同工况下石英砂与柱形生物质颗粒混合双组分颗粒的流动特性。柱形生物质颗粒尺寸为10 mm×10 mm(直径×长),石英砂粒径为0.8 mm。在鼓泡床阶段,随着生物质含量的增加,系统的周期性呈现先减弱再增强的变化趋势;该阶段确定性与层流率均表现为随气速的增加而增大,其值在生物质含量低时会明显减小,系统熵则随着气速的增大而减小。在腾涌阶段,生物质添加前后系统信号的递归图呈现相似的纹理特征,确定性与层流率变化较小,此时熵随着气速的增加而减小,与单组分流动呈现相反的趋势。 展开更多
关键词 递归图 递归定量分析 生物质 混合 流化床 混沌
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RQA在肌电分析中的应用 被引量:19
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作者 钟季康 宋志怀 郝为强 《生物物理学报》 CAS CSCD 北大核心 2002年第2期241-245,共5页
介绍了递归图的生成方法和定量递归分析 (RQA)中递归点的百分数 ,确定性线段的百分数,线段分布香农熵等分析量的意义。应用RQA分析了肱二头肌及肱桡肌在不同负重下的肌电信号 ,发现肱二头肌肌电信号的递归点百分数均比肱肌高,有较强的... 介绍了递归图的生成方法和定量递归分析 (RQA)中递归点的百分数 ,确定性线段的百分数,线段分布香农熵等分析量的意义。应用RQA分析了肱二头肌及肱桡肌在不同负重下的肌电信号 ,发现肱二头肌肌电信号的递归点百分数均比肱肌高,有较强的周期性嵌入。与同一信号所作的FFT谱分析相比较 ,RQA法有较高的区分灵敏性 ,是肌电分析的一种新方法 。 展开更多
关键词 定量递归分析 递归点百分数 确定线段百分数 RQA 肌电分析 应用
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基于局部递归率分析的振动信号非平稳评价 被引量:7
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作者 杨栋 任伟新 +1 位作者 李丹 胡异丁 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第7期3024-3032,共9页
针对土木工程结构环境振动信号非平稳程度评价的问题,提出一种新的基于递归量化分析的评价环境振动信号非平稳程度指标。首先,研究递归图中反映信号非平稳特征的模式,根据递归量化分析中已有的信号非平稳程度评价指标即递归趋势应用于... 针对土木工程结构环境振动信号非平稳程度评价的问题,提出一种新的基于递归量化分析的评价环境振动信号非平稳程度指标。首先,研究递归图中反映信号非平稳特征的模式,根据递归量化分析中已有的信号非平稳程度评价指标即递归趋势应用于土木工程结构环境振动信号时的不足,将质量损失函数理论引入递归量化分析,分析递归图中局部递归率的变化情况,并以最小局部递归率为基准,提出一个新的衡量信号非平稳程度的指标——递归损失量;然后,以几种典型的非平稳信号为例,分别计算2种非平稳评价指标并进行对比分析,讨论其差异及各自不同的适用条件;最后,将指标用于桥梁结构环境振动信号的非平稳程度评价。计算结果表明:提出的递归损失量比递归趋势更能适应环境振动信号的特点,能够对环境振动信号的非平稳程度进行更客观的评价。 展开更多
关键词 非平稳程度 递归图 递归量化分析 质量损失函数 环境振动信号
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基于递归定量分析的冠心病中医脉象特征提取与分析 被引量:21
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作者 郭睿 王忆勤 +2 位作者 颜建军 燕海霞 杨育慈 《中西医结合学报》 CAS 2011年第11期1226-1233,共8页
目的:基于非线性动力学方法研究冠心病患者的脉象,寻找能区分冠心病和正常人脉象的非线性动力学参数。方法:基于非线性动力学理论,对63例冠心病患者和61例正常人的脉搏信号的递归图进行递归定量分析(recurrence quantification analysis... 目的:基于非线性动力学方法研究冠心病患者的脉象,寻找能区分冠心病和正常人脉象的非线性动力学参数。方法:基于非线性动力学理论,对63例冠心病患者和61例正常人的脉搏信号的递归图进行递归定量分析(recurrence quantification analysis,RQA),计算两组脉搏信号的RQA参数,这些参数包括递归率(recurrence rate,RR)、确定性(determinism,DET)、对角线长度的均值(averaged diagonal length,L)、递归熵(entropy of diagonal length,ENTR)、最长对角线(length of longest diagonal line,L_(max))、层状度(laminarity,LAM),竖直/水平线段长度均值(trapping time,TT)和最长竖直/水平线段长度(length of longest vertical line,V_(max));并用秩和检验统计两组脉搏信号的RQA参数之间的差异,用箱线图(BoxPlot)观察有显著性差异的RQA参数的数值分布;绘制有显著性差异的RQA参数的接受者工作特征(receiver operatingcharacteristic,ROC)曲线,对RQA参数进行诊断性试验,以评估脉搏信号的RQA参数区分冠心病组和正常组的诊断价值。结果:秩和检验统计结果表明冠心病组脉搏信号的RQA参数中RR、DET、L、ENTR、LAM、TT和V_(max)的平均秩次显著大于正常组,它们的ROC曲线下的面积依次为1.000、0.898、0.653、0.673、0.885、0.898、0.986和0.994。结论:与正常组相比,冠心病组的脉搏信号表现出较高的规律性、确定性和稳定性;脉象的非线性动力学RQA参数RR、TT、V_(max)DET和LAM对区分冠心病组和正常组具有较高的诊断价值。这为脉诊的无损伤检测提供了新的手段。 展开更多
关键词 冠心病 脉象 递归定量分析 脉象图 临床试验
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基于非线性时间序列分析的短时交通流特性分析 被引量:6
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作者 许伦辉 唐德华 +1 位作者 邹娜 夏新海 《重庆交通大学学报(自然科学版)》 CAS 北大核心 2010年第1期110-113,共4页
利用非线性时间序列分析方法对从时间一维角度出发对短时交通流的特性进行定性、定量分析。首先简要介绍了递归图和定量递归分析方法,以1min为间隔的实测交通流量数据为例,选取1d中不同的4部分,用递归图从定性方面可视化其动力学特性,... 利用非线性时间序列分析方法对从时间一维角度出发对短时交通流的特性进行定性、定量分析。首先简要介绍了递归图和定量递归分析方法,以1min为间隔的实测交通流量数据为例,选取1d中不同的4部分,用递归图从定性方面可视化其动力学特性,然后用定量递归分析得到各部分的量化特征值,并对结果做出分析。结果表明短时交通流时间序列具有非线性、非平稳的特性,在不同的时段内分别具有随机性、混沌性和确定性。这一研究结果对短时交通流的预测具有一定的理论价值和实际意义。 展开更多
关键词 短时交通流 非线性 递归图 定量递归分析 预测性分析
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交叉递归图在变压器铁芯压紧力变化检测中的应用 被引量:16
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作者 郭洁 陈祥献 黄海 《高电压技术》 EI CAS CSCD 北大核心 2010年第11期2731-2738,共8页
基于交叉递归图(CRP)能够对信号的非线性非平稳变化进行检测的特点,提出了一种基于CRP的铁芯连续压紧力变化的检测方法。首先对铁芯在压紧力单调下降情况下的振动信号进行递归图分析,根据铁芯振动信号的特点经验性地选择距离阈值ε,然... 基于交叉递归图(CRP)能够对信号的非线性非平稳变化进行检测的特点,提出了一种基于CRP的铁芯连续压紧力变化的检测方法。首先对铁芯在压紧力单调下降情况下的振动信号进行递归图分析,根据铁芯振动信号的特点经验性地选择距离阈值ε,然后分别采用一元和多元传感器信号进行相空间重构并进行递归图分析,计算铁芯全局和局部的压紧力的4个基于对角线结构的递归度量分析(RQA)度量,对铁芯压紧力的变化从总体角度和局部角度分别进行衡量。对实验数据使用该方法的分析表明,选取的4个度量在一定压紧力范围内随压紧力的下降而单调下降,多个RQA参数结合能够有效地表征铁芯压紧力的变化趋势。该方法能较好地反映铁芯结构发生的非线性变化,能有效地监测铁芯松动故障。 展开更多
关键词 电力变压器 铁芯振动 压紧力 交叉递归图(CRP) 递归度量分析(RQA) 递归率
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