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Partial Discharge Fault Diagnosis in Power Transformers Based on SGMD Approximate Entropy and Optimized BILSTM 基于 SGMD 近似熵和优化 BILSTM 的电力变压器局部放电故障诊断
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-27 DOI: 10.3390/e26070551
Haikun Shang, Zixuan Zhao, Jiawen Li, Zhiming Wang
Partial discharge (PD) fault diagnosis is of great importance for ensuring the safe and stable operation of power transformers. To address the issues of low accuracy in traditional PD fault diagnostic methods, this paper proposes a novel method for the power transformer PD fault diagnosis. It incorporates the approximate entropy (ApEn) of symplectic geometry mode decomposition (SGMD) into the optimized bidirectional long short-term memory (BILSTM) neural network. This method extracts dominant PD features employing SGMD and ApEn. Meanwhile, it improves the diagnostic accuracy with the optimized BILSTM by introducing the golden jackal optimization (GJO). Simulation studies evaluate the performance of FFT, EMD, VMD, and SGMD. The results show that SGMD–ApEn outperforms other methods in extracting dominant PD features. Experimental results verify the effectiveness and superiority of the proposed method by comparing different traditional methods. The proposed method improves PD fault recognition accuracy and provides a diagnostic rate of 98.6%, with lower noise sensitivity.
局部放电(PD)故障诊断对确保电力变压器的安全稳定运行具有重要意义。针对传统局部放电故障诊断方法准确度低的问题,本文提出了一种新型的电力变压器局部放电故障诊断方法。该方法将交映几何模式分解(SGMD)的近似熵(ApEn)融入到优化的双向长短期记忆(BILSTM)神经网络中。该方法利用 SGMD 和 ApEn 提取了主要的 PD 特征。同时,它通过引入金豺优化(GJO)提高了优化 BILSTM 的诊断准确性。仿真研究评估了 FFT、EMD、VMD 和 SGMD 的性能。结果表明,SGMD-ApEn 在提取 PD 主要特征方面优于其他方法。通过比较不同的传统方法,实验结果验证了所提方法的有效性和优越性。所提出的方法提高了 PD 故障识别准确率,诊断率达到 98.6%,噪声灵敏度更低。
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引用次数: 0
Avionics Module Fault Diagnosis Algorithm Based on Hybrid Attention Adaptive Multi-Scale Temporal Convolution Network 基于混合注意力自适应多尺度时空卷积网络的航空电子模块故障诊断算法
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-27 DOI: 10.3390/e26070550
Qiliang Du, Mingde Sheng, Lubin Yu, Zhenwei Zhou, Lianfang Tian, Shilie He
Since the reliability of the avionics module is crucial for aircraft safety, the fault diagnosis and health management of this module are particularly significant. While deep learning-based prognostics and health management (PHM) methods exhibit highly accurate fault diagnosis, they have disadvantages such as inefficient data feature extraction and insufficient generalization capability, as well as a lack of avionics module fault data. Consequently, this study first employs fault injection to simulate various fault types of the avionics module and performs data enhancement to construct the P2020 communications processor fault dataset. Subsequently, a multichannel fault diagnosis method, the Hybrid Attention Adaptive Multi-scale Temporal Convolution Network (HAAMTCN) for the integrated functional circuit module of the avionics module, is proposed, which adaptively constructs the optimal size of the convolutional kernel to efficiently extract features of avionics module fault signals with large information entropy. Further, the combined use of the Interaction Channel Attention (ICA) module and the Hierarchical Block Temporal Attention (HBTA) module results in the HAAMTCN to pay more attention to the critical information in the channel dimension and time step dimension. The experimental results show that the HAAMTCN achieves an accuracy of 99.64% in the avionics module fault classification task which proves our method achieves better performance in comparison with existing methods.
由于航空电子模块的可靠性对飞机安全至关重要,因此该模块的故障诊断和健康管理尤为重要。基于深度学习的预知和健康管理(PHM)方法虽然具有高精度的故障诊断能力,但也存在数据特征提取效率低、泛化能力不足等缺点,而且缺乏航空电子模块的故障数据。因此,本研究首先采用故障注入法模拟航空电子模块的各种故障类型,并进行数据增强以构建 P2020 通信处理器故障数据集。随后,针对航空电子模块的集成功能电路模块,提出了一种多通道故障诊断方法--混合注意力自适应多尺度时空卷积网络(HAAMTCN),该方法可自适应地构建最佳卷积核大小,以有效提取具有较大信息熵的航空电子模块故障信号特征。此外,结合使用交互信道注意(ICA)模块和层次块时态注意(HBTA)模块,HAAMTCN 能够更加关注信道维度和时间步维度的关键信息。实验结果表明,在航空电子模块故障分类任务中,HAAMTCN 的准确率达到 99.64%,这证明我们的方法与现有方法相比具有更好的性能。
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引用次数: 0
Early Warning of Systemic Risk in Commodity Markets Based on Transfer Entropy Networks: Evidence from China 基于转移熵网络的商品市场系统性风险预警:来自中国的证据
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-27 DOI: 10.3390/e26070549
Yiran Zhao, Xiangyun Gao, Hongyu Wei, Xiaotian Sun, Sufang An
This study aims to employ a causal network model based on transfer entropy for the early warning of systemic risk in commodity markets. We analyzed the dynamic causal relationships of prices for 25 commodities related to China (including futures and spot prices of energy, industrial metals, precious metals, and agricultural products), validating the effect of the causal network structure among commodity markets on systemic risk. Our research results identified commodities and categories playing significant roles, revealing that industry and precious metal markets possess stronger market information transmission capabilities, with price fluctuations impacting a broader range and with greater force on other commodity markets. Under the influence of different types of crisis events, such as economic crises and the Russia–Ukraine conflict, the causal network structure among commodity markets exhibited distinct characteristics. The results of the effect of external shocks to the causal network structure of commodity markets on the entropy of systemic risk suggest that network structure indicators can warn of systemic risk. This article can assist investors and policymakers in managing systemic risk to avoid unexpected losses.
本研究旨在运用基于转移熵的因果网络模型来预警大宗商品市场的系统性风险。我们分析了与中国相关的 25 种商品(包括能源、工业金属、贵金属和农产品的期货和现货价格)价格的动态因果关系,验证了商品市场之间的因果网络结构对系统风险的影响。研究结果表明,工业品和贵金属市场具有更强的市场信息传递能力,其价格波动对其他商品市场的影响范围更广、力度更大。在经济危机、俄乌冲突等不同类型危机事件的影响下,商品市场之间的因果网络结构表现出明显的特征。外部冲击对商品市场因果网络结构的影响对系统风险熵的影响结果表明,网络结构指标可以预警系统风险。本文有助于投资者和决策者管理系统性风险,避免意外损失。
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引用次数: 0
Relativistic Consistency of Nonlocal Quantum Correlations 非局部量子关联的相对论一致性
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-27 DOI: 10.3390/e26070548
Christian Beck, Dustin Lazarovici
What guarantees the “peaceful coexistence” of quantum nonlocality and special relativity? The tension arises because entanglement leads to locally inexplicable correlations between distant events that have no absolute temporal order in relativistic spacetime. This paper identifies a relativistic consistency condition that is weaker than Bell locality but stronger than the no-signaling condition meant to exclude superluminal communication. While justifications for the no-signaling condition often rely on anthropocentric arguments, relativistic consistency is simply the requirement that joint outcome distributions for spacelike separated measurements (or measurement-like processes) must be independent of their temporal order. This is necessary to obtain consistent statistical predictions across different Lorentz frames. We first consider ideal quantum measurements, derive the relevant consistency condition on the level of probability distributions, and show that it implies no-signaling (but not vice versa). We then extend the results to general quantum operations and derive corresponding operator conditions. This will allow us to clarify the relationships between relativistic consistency, no-signaling, and local commutativity. We argue that relativistic consistency is the basic physical principle that ensures the compatibility of quantum statistics and relativistic spacetime structure, while no-signaling and local commutativity can be justified on this basis.
是什么保证了量子非位置性与狭义相对论的 "和平共处"?产生矛盾的原因是纠缠会导致遥远事件之间产生无法解释的局部相关性,而这种相关性在相对论时空中没有绝对的时间顺序。本文确定了一个相对论一致性条件,它弱于贝尔位置性,但强于旨在排除超光速通信的无信号条件。无信号条件的理由通常依赖于人类中心论的论据,而相对论一致性只是要求类似空间的分离测量(或类似测量过程)的联合结果分布必须与它们的时间顺序无关。这是在不同洛伦兹框架下获得一致的统计预测所必需的。我们首先考虑理想量子测量,推导出概率分布层面上的相关一致性条件,并证明它意味着无信号(反之亦然)。然后,我们将结果扩展到一般量子操作,并推导出相应的算子条件。这将使我们能够澄清相对论一致性、无信号和局部交换性之间的关系。我们认为相对论一致性是确保量子统计与相对论时空结构相容的基本物理原理,而无信号性和局部换向性也可以在此基础上得到证明。
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引用次数: 0
Information Theory in Emerging Wireless Communication Systems and Networks 新兴无线通信系统和网络中的信息论
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-26 DOI: 10.3390/e26070543
Erdem Koyuncu
Wireless communication systems and networks are rapidly evolving to meet the increasing demands for higher data rates, better reliability, and connectivity anywhere, anytime [...]
无线通信系统和网络正在迅速发展,以满足人们对更高数据传输速率、更高可靠性以及随时随地进行连接的日益增长的需求 [...]
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引用次数: 0
Partial Information Decomposition: Redundancy as Information Bottleneck 部分信息分解:冗余是信息瓶颈
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-26 DOI: 10.3390/e26070546
Artemy Kolchinsky
The partial information decomposition (PID) aims to quantify the amount of redundant information that a set of sources provides about a target. Here, we show that this goal can be formulated as a type of information bottleneck (IB) problem, termed the “redundancy bottleneck” (RB). The RB formalizes a tradeoff between prediction and compression: it extracts information from the sources that best predict the target, without revealing which source provided the information. It can be understood as a generalization of “Blackwell redundancy”, which we previously proposed as a principled measure of PID redundancy. The “RB curve” quantifies the prediction–compression tradeoff at multiple scales. This curve can also be quantified for individual sources, allowing subsets of redundant sources to be identified without combinatorial optimization. We provide an efficient iterative algorithm for computing the RB curve.
部分信息分解(PID)旨在量化一组信息源提供的关于目标的冗余信息量。在这里,我们将证明这一目标可以表述为一种信息瓶颈(IB)问题,即 "冗余瓶颈"(RB)。RB 形式化了预测和压缩之间的权衡:它从最能预测目标的信息源中提取信息,而不透露提供信息的信息源。它可以理解为 "布莱克韦尔冗余度 "的一般化,我们之前曾提出过 "布莱克韦尔冗余度 "作为 PID 冗余度的原则性衡量标准。RB 曲线 "在多个尺度上量化了预测与压缩之间的权衡。该曲线还可以对单个信号源进行量化,从而无需组合优化就能识别冗余信号源子集。我们提供了一种计算 RB 曲线的高效迭代算法。
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引用次数: 0
Adaptive Joint Carrier and DOA Estimations of FHSS Signals Based on Knowledge-Enhanced Compressed Measurements and Deep Learning 基于知识增强型压缩测量和深度学习的 FHSS 信号的自适应联合载波和 DOA 估计
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-26 DOI: 10.3390/e26070544
Yinghai Jiang, Feng Liu
As one of the most widely used spread spectrum techniques, the frequency-hopping spread spectrum (FHSS) has been widely adopted in both civilian and military secure communications. In this technique, the carrier frequency of the signal hops pseudo-randomly over a large range, compared to the baseband. To capture an FHSS signal, conventional non-cooperative receivers without knowledge of the carrier have to operate at a high sampling rate covering the entire FHSS hopping range, according to the Nyquist sampling theorem. In this paper, we propose an adaptive compressed method for joint carrier and direction of arrival (DOA) estimations of FHSS signals, enabling subsequent non-cooperative processing. The compressed measurement kernels (i.e., non-zero entries in the sensing matrix) have been adaptively designed based on the posterior knowledge of the signal and task-specific information optimization. Moreover, a deep neural network has been designed to ensure the efficiency of the measurement kernel design process. Finally, the signal carrier and DOA are estimated based on the measurement data. Through simulations, the performance of the adaptively designed measurement kernels is proved to be improved over the random measurement kernels. In addition, the proposed method is shown to outperform the compressed methods in the literature.
作为应用最广泛的扩频技术之一,跳频扩频(FHSS)已被广泛应用于民用和军用安全通信领域。在这种技术中,与基带相比,信号的载波频率在很大范围内进行伪随机跳变。为了捕获 FHSS 信号,根据奈奎斯特采样定理,不知道载波的传统非合作接收器必须以覆盖整个 FHSS 跳频范围的高采样率工作。在本文中,我们提出了一种自适应压缩方法,用于联合估计 FHSS 信号的载波和到达方向(DOA),从而实现后续的非协同处理。压缩测量内核(即传感矩阵中的非零项)是根据信号的后验知识和特定任务的信息优化自适应设计的。此外,还设计了一个深度神经网络,以确保测量内核设计过程的效率。最后,根据测量数据估计信号载波和 DOA。通过仿真证明,自适应设计的测量核的性能比随机测量核有所提高。此外,还证明所提出的方法优于文献中的压缩方法。
{"title":"Adaptive Joint Carrier and DOA Estimations of FHSS Signals Based on Knowledge-Enhanced Compressed Measurements and Deep Learning","authors":"Yinghai Jiang, Feng Liu","doi":"10.3390/e26070544","DOIUrl":"https://doi.org/10.3390/e26070544","url":null,"abstract":"As one of the most widely used spread spectrum techniques, the frequency-hopping spread spectrum (FHSS) has been widely adopted in both civilian and military secure communications. In this technique, the carrier frequency of the signal hops pseudo-randomly over a large range, compared to the baseband. To capture an FHSS signal, conventional non-cooperative receivers without knowledge of the carrier have to operate at a high sampling rate covering the entire FHSS hopping range, according to the Nyquist sampling theorem. In this paper, we propose an adaptive compressed method for joint carrier and direction of arrival (DOA) estimations of FHSS signals, enabling subsequent non-cooperative processing. The compressed measurement kernels (i.e., non-zero entries in the sensing matrix) have been adaptively designed based on the posterior knowledge of the signal and task-specific information optimization. Moreover, a deep neural network has been designed to ensure the efficiency of the measurement kernel design process. Finally, the signal carrier and DOA are estimated based on the measurement data. Through simulations, the performance of the adaptively designed measurement kernels is proved to be improved over the random measurement kernels. In addition, the proposed method is shown to outperform the compressed methods in the literature.","PeriodicalId":11694,"journal":{"name":"Entropy","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141522036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Dynamic Entropy Approach Reveals Reduced Functional Network Connectivity Trajectory Complexity in Schizophrenia 动态熵方法揭示了精神分裂症患者功能网络连接轨迹复杂性的降低
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-26 DOI: 10.3390/e26070545
David Sutherland Blair, Robyn L. Miller, Vince D. Calhoun
Over the past decade and a half, dynamic functional imaging has revealed low-dimensional brain connectivity measures, identified potential common human spatial connectivity states, tracked the transition patterns of these states, and demonstrated meaningful transition alterations in disorders and over the course of development. Recently, researchers have begun to analyze these data from the perspective of dynamic systems and information theory in the hopes of understanding how these dynamics support less easily quantified processes, such as information processing, cortical hierarchy, and consciousness. Little attention has been paid to the effects of psychiatric disease on these measures, however. We begin to rectify this by examining the complexity of subject trajectories in state space through the lens of information theory. Specifically, we identify a basis for the dynamic functional connectivity state space and track subject trajectories through this space over the course of the scan. The dynamic complexity of these trajectories is assessed along each dimension of the proposed basis space. Using these estimates, we demonstrate that schizophrenia patients display substantially simpler trajectories than demographically matched healthy controls and that this drop in complexity concentrates along specific dimensions. We also demonstrate that entropy generation in at least one of these dimensions is linked to cognitive performance. Overall, the results suggest great value in applying dynamic systems theory to problems of neuroimaging and reveal a substantial drop in the complexity of schizophrenia patients’ brain function.
在过去的十五年里,动态功能成像技术揭示了低维大脑连通性测量方法,识别了潜在的人类常见空间连通性状态,追踪了这些状态的转换模式,并证明了在疾病和发育过程中发生的有意义的转换改变。最近,研究人员开始从动态系统和信息理论的角度分析这些数据,希望了解这些动态如何支持信息处理、皮层层次结构和意识等不易量化的过程。然而,人们很少关注精神疾病对这些测量结果的影响。我们从信息论的视角出发,研究受试者在状态空间中轨迹的复杂性,从而开始纠正这一问题。具体来说,我们确定了动态功能连接状态空间的基础,并在扫描过程中追踪受试者在该空间中的轨迹。这些轨迹的动态复杂性将沿着所提出的基础空间的每个维度进行评估。利用这些估计值,我们证明精神分裂症患者显示的轨迹比人口统计学上匹配的健康对照组要简单得多,而且这种复杂性的下降集中在特定维度上。我们还证明,这些维度中至少有一个维度的熵产生与认知表现有关。总之,研究结果表明,将动态系统理论应用于神经成像问题具有重要价值,并揭示了精神分裂症患者大脑功能复杂性的大幅下降。
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引用次数: 0
A Partial Information Decomposition for Multivariate Gaussian Systems Based on Information Geometry 基于信息几何的多变量高斯系统部分信息分解
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-25 DOI: 10.3390/e26070542
Jim W. Kay
There is much interest in the topic of partial information decomposition, both in developing new algorithms and in developing applications. An algorithm, based on standard results from information geometry, was recently proposed by Niu and Quinn (2019). They considered the case of three scalar random variables from an exponential family, including both discrete distributions and a trivariate Gaussian distribution. The purpose of this article is to extend their work to the general case of multivariate Gaussian systems having vector inputs and a vector output. By making use of standard results from information geometry, explicit expressions are derived for the components of the partial information decomposition for this system. These expressions depend on a real-valued parameter which is determined by performing a simple constrained convex optimisation. Furthermore, it is proved that the theoretical properties of non-negativity, self-redundancy, symmetry and monotonicity, which were proposed by Williams and Beer (2010), are valid for the decomposition Iig derived herein. Application of these results to real and simulated data show that the Iig algorithm does produce the results expected when clear expectations are available, although in some scenarios, it can overestimate the level of the synergy and shared information components of the decomposition, and correspondingly underestimate the levels of unique information. Comparisons of the Iig and Idep (Kay and Ince, 2018) methods show that they can both produce very similar results, but interesting differences are provided. The same may be said about comparisons between the Iig and Immi (Barrett, 2015) methods.
无论是在开发新算法还是在开发应用方面,人们都对部分信息分解这一主题兴趣浓厚。Niu 和 Quinn(2019)最近提出了一种基于信息几何学标准结果的算法。他们考虑了指数族中三个标量随机变量的情况,包括离散分布和三元高斯分布。本文旨在将他们的工作扩展到具有向量输入和向量输出的多变量高斯系统的一般情况。通过利用信息几何学的标准结果,我们得出了该系统部分信息分解分量的明确表达式。这些表达式取决于一个实值参数,该参数可通过执行简单的约束凸优化来确定。此外,本文还证明了 Williams 和 Beer(2010 年)提出的非负性、自冗余性、对称性和单调性等理论属性对本文推导的分解 Iig 有效。将这些结果应用于真实数据和模拟数据表明,在有明确预期的情况下,Iig 算法确实能产生预期的结果,不过在某些情况下,它可能会高估分解的协同作用和共享信息成分的水平,并相应地低估独特信息的水平。对 Iig 和 Idep(Kay 和 Ince,2018 年)方法的比较表明,它们都能产生非常相似的结果,但也存在有趣的差异。Iig 和 Immi(Barrett,2015 年)方法之间的比较也是如此。
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引用次数: 0
Causalized Convergent Cross Mapping and Its Implementation in Causality Analysis 因果化收敛交叉映射及其在因果关系分析中的应用
IF 2.7 3区 物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY Pub Date : 2024-06-24 DOI: 10.3390/e26070539
Boxin Sun, Jinxian Deng, Norman Scheel, David C. Zhu, Jian Ren, Rong Zhang, Tongtong Li
Rooted in dynamic systems theory, convergent cross mapping (CCM) has attracted increased attention recently due to its capability in detecting linear and nonlinear causal coupling in both random and deterministic settings. One limitation with CCM is that it uses both past and future values to predict the current value, which is inconsistent with the widely accepted definition of causality, where it is assumed that the future values of one process cannot influence the past of another. To overcome this obstacle, in our previous research, we introduced the concept of causalized convergent cross mapping (cCCM), where future values are no longer used to predict the current value. In this paper, we focus on the implementation of cCCM in causality analysis. More specifically, we demonstrate the effectiveness of cCCM in identifying both linear and nonlinear causal coupling in various settings through a large number of examples, including Gaussian random variables with additive noise, sinusoidal waveforms, autoregressive models, stochastic processes with a dominant spectral component embedded in noise, deterministic chaotic maps, and systems with memory, as well as experimental fMRI data. In particular, we analyze the impact of shadow manifold construction on the performance of cCCM and provide detailed guidelines on how to configure the key parameters of cCCM in different applications. Overall, our analysis indicates that cCCM is a promising and easy-to-implement tool for causality analysis in a wide spectrum of applications.
收敛交叉映射(CCM)植根于动态系统理论,由于其在随机和确定性环境中检测线性和非线性因果耦合的能力,最近吸引了越来越多的关注。收敛交叉映射的一个局限是,它同时使用过去和未来的值来预测当前值,这与广为接受的因果关系定义不一致,因为在因果关系定义中,假定一个过程的未来值不能影响另一个过程的过去值。为了克服这一障碍,我们在之前的研究中引入了因果收敛交叉映射(cCCM)的概念,即不再使用未来值来预测当前值。在本文中,我们将重点讨论 cCCM 在因果关系分析中的应用。更具体地说,我们通过大量实例证明了 cCCM 在各种环境下识别线性和非线性因果耦合的有效性,这些实例包括带有加性噪声的高斯随机变量、正弦波形、自回归模型、带有嵌入噪声的主导频谱分量的随机过程、确定性混沌映射、具有记忆的系统以及实验性 fMRI 数据。我们特别分析了阴影流形构造对 cCCM 性能的影响,并就如何在不同应用中配置 cCCM 的关键参数提供了详细指导。总之,我们的分析表明,cCCM 是一种前景广阔且易于实施的因果关系分析工具,适用于广泛的应用领域。
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引用次数: 0
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