Multitaper
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Sleep Neurophysiological Dynamics Through the Lens of Multitaper Spectral Analysis Open
During sleep, cortical and subcortical structures within the brain engage in highly structured oscillatory dynamics that can be observed in the electroencephalogram (EEG). The ability to accurately describe changes in sleep state from thes…
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Seismic features and automatic discrimination of deep and shallow induced-microearthquakes using neural network and logistic regression Open
We develop an automated strategy for discriminating deep microseismic events from shallow ones on the basis of the waveforms recorded on a limited number of surface receivers. Machine-learning techniques are employed to explore the relatio…
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A Novel Neural Network Model for Blood Pressure Estimation Using Photoplethesmography without Electrocardiogram Open
The prevention, evaluation, and treatment of hypertension have attracted increasing attention in recent years. As photoplethysmography (PPG) technology has been widely applied to wearable sensors, the noninvasive estimation of blood pressu…
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Bispectrum Inversion With Application to Multireference Alignment Open
We consider the problem of estimating a signal from noisy circularly-translated versions of itself, called multireference alignment (MRA). One natural approach to MRA could be to estimate the shifts of the observations first, and infer the…
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Comparison of Matching Pursuit Algorithm with Other Signal Processing Techniques for Computation of the Time-Frequency Power Spectrum of Brain Signals Open
Signals recorded from the brain often show rhythmic patterns at different frequencies, which are tightly coupled to the external stimuli as well as the internal state of the subject. In addition, these signals have very transient structure…
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State-space multitaper time-frequency analysis Open
Significance Rapid growth in sensor and recording technologies is spurring rapid growth in time series data. Nonstationary and oscillatory structure in time series is commonly analyzed using time-varying spectral methods. These widely used…
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Common-spectrum process versus cross-correlation for gravitational-wave searches using pulsar timing arrays Open
The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has recently reported strong statistical evidence for a common-spectrum red-noise process for all pulsars, as seen in their 12.5-yr analysis for an isotropic stoch…
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Optimally band-limited spectroscopy of control noise using a qubit sensor Open
Classical control noise is ubiquitous in qubit devices, making its accurate\nspectral characterization essential for designing optimized error suppression\nstrategies at the physical level. Here, we focus on multiplicative Gaussian\namplit…
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Dexmedetomidine-induced deep sedation mimics non-rapid eye movement stage 3 sleep: large-scale validation using machine learning Open
Study Objectives Dexmedetomidine-induced electroencephalogram (EEG) patterns during deep sedation are comparable with natural sleep patterns. Using large-scale EEG recordings and machine learning techniques, we investigated whether dexmede…
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Power Spectral Density Background Estimate and Signal Detection via the Multitaper Method Open
We present a new spectral analysis method for the identification of periodic signals in geophysical time series. We evaluate the power spectral density with the adaptive multitaper method, a nonparametric spectral analysis technique suitab…
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Optimal Bandwidth for Multitaper Spectrum Estimation Open
A systematic method for bandwidth parameter selection is desired for Thomson multitaper spectrum estimation. We give a method for determining the optimal bandwidth based on a mean squared error (MSE) criterion. When the true spectrum has a…
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Comparing estimation techniques for temporal scaling in palaeoclimate time series Open
Characterizing the variability across timescales is important for understanding the underlying dynamics of the Earth system. It remains challenging to do so from palaeoclimate archives since they are more often than not irregular, and trad…
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Electroencephalographic features of discontinuous activity in anesthetized infants and children Open
Discontinuous activity in children reflects a state of a younger or more deeply anesthetized brain, and characteristic features of discontinuous activity evolve with age and may reflect neurodevelopment.
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Improving the Lomb–Scargle Periodogram with the Thomson Multitaper Open
A common approach for characterizing the properties of time-series data that are evenly sampled in time is to estimate the power spectrum of the data using the periodogram. The periodogram as an estimator of the spectrum is (1) statistical…
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Learning-Based Instantaneous Drowsiness Detection Using Wired and Wireless Electroencephalography Open
Instantaneous drowsiness (i.e., lapse or micro-sleep) during various activities such as driving or construction causes enormous socioeconomic losses. Thus, a virtuous cycle system that monitors a subject's drowsiness can improve work effic…
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Linking visual gamma to task‐related brain networks—a simultaneous EEG‐fMRI study Open
There is a growing interest in human gamma‐band oscillatory activity due to its direct link to neuronal populations, its associations with many cognitive processes, and its positive relationship with fMRI BOLD signal. Visual gamma has been…
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Time-Domain Multidimensional Deconvolution: A Physically Reliable and Stable Preconditioned Implementation Open
Multidimensional deconvolution constitutes an essential operation in a variety of geophysical scenarios at different scales ranging from reservoir to crustal, as it appears in applications such as surface multiple elimination, target-orien…
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Timing-residual power spectrum of a polarized stochastic gravitational-wave background in pulsar-timing-array observation Open
We study the observation of stochastic gravitational-wave background (SGWB)\nmade by pulsar-timing arrays in the spherical harmonic space. Instead of using\nthe Shapiro time delay, we keep the Sachs-Wolfe line-of-sight integral for the\nti…
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Estimation of the Evolutionary Spectra With Application to Stationarity Test Open
In this work, we propose a new inference procedure for understanding non-stationary processes, under the framework of evolutionary spectra developed by Priestley. Among various frameworks of modeling non-stationary processes, the distingui…
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Optimized workflows for high-frequency seismic interferometry using dense arrays Open
SUMMARY High-frequency seismic surface waves sample the top few tens of meters to the top few kilometres of the subsurface. They can be used to determine 3-D distributions of shear-wave velocities and to map the depths of discontinuities (…
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Computer-based Multitaper Spectrogram Program for Electroencephalographic Data Open
Current web resources provide limited, user friendly tools to compute spectrograms for visualizing and quantifying electroencephalographic (EEG) data. This paper describes a Windows-based, open source code for creating EEG multitaper spect…
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Sparse Autoregressive Modeling via the Least Absolute LP-Norm Penalized Solution Open
The conventional autoregressive (AR) model has been widely applied in the various electroencephalogram (EEG) analyses such as spectrum estimation, waveform fittings, and in classification tasks. Nevertheless, evoked EEG is usually inevitab…
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Seismic noise monitoring of a small rock block collapse test Open
SUMMARY We tested the capability of seismic noise to monitor the stability conditions of a small rock block that we forced to fail in four following stages. Ambient vibrations were recorded with a broad-band 3C seismometer placed on top of…
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The multitaper reassigned spectrogram for oscillating transients with Gaussian envelopes Open
Joint time-frequency representations are important tools when estimating the instantaneous frequency. The widely used spectrogram is known to have poor energy localisation, which the reassignment method improves. However, the reassignment …
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Frequency–wavenumber spectral analysis of spatio-temporal flows Open
We propose a fully spatio-temporal approach for identifying spatially varying modes of oscillation in fluid dynamics simulation output by means of multitaper frequency–wavenumber spectral analysis. One-dimensional spectrum estimation has p…
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Electroencephalogram Similarity Analysis Using Temporal and Spectral Dynamics Analysis for Propofol and Desflurane Induced Unconsciousness Open
Important information about the state dynamics of the brain during anesthesia is unraveled by Electroencephalogram (EEG) approaches. Patterns that are observed through EEG related to neural circuit mechanism under different molecular targe…
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A multitaper spectral estimator for time-series with missing data Open
SUMMARY A multitaper estimator is proposed that accommodates time-series containing gaps without using any form of interpolation. In contrast with prior missing-data multitaper estimators that force standard Slepian sequences to be zero at…
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Double-difference measurements in global full-waveform inversions Open
SUMMARY We demonstrate double-difference (DD) tomography, a method involving differential measurements between stations, for 2-D and 3-D adjoint inversions based on realistic source–receiver distributions, with a focus on the global scale.…
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Training Based Channel Estimation for Multitaper GFDM System Open
Recent activities in the cellular network world clearly show the need to design new physical layer waveforms in order to meet future wireless requirements. Generalized Frequency Division Multiplexing (GFDM) is one of the leading candidates…
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Rules-Based and SVM-Q Methods With Multitapers and Convolution for Sleep EEG Stages Classification Open
Sleep EEG signals analysis is an approach that helps researchers identify and understand the different phenomena concealed within sleep EEG data. This research introduces a time-frequency analysis approach to untangle the parameters of the…