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Possible Patient Early Diagnosis by Ultrasonic Noninvasive Estimation of Thermal Gradients into Tissues Based on Spectral Changes Modeling

I. Bazan, A. Ramos, H. Calas, A. Ramirez, R. Pintle, T. E. Gomez, C. Negreira, F. J. Gallegos, A. J. Rosales
2012 Computational and Mathematical Methods in Medicine  
Computer methods are provided for viability evaluation of thermal estimation from echoes with distinct noise levels, difficult to be interpreted, and its effectiveness is evaluated as possible diagnosis  ...  Before their implementations with ultrasonic probes and real-time electronic and processing systems, rigorous analyses must be still made over transient echotraces acquired from well-controlled biological  ...  In addition, the Burg method is applied here as an alternative option to the classical approach for power spectrum estimation, giving a better final frequency resolution.  ... 
doi:10.1155/2012/275405 pmid:22654958 pmcid:PMC3359682 fatcat:irtlpxj3zfegbnmogaoumfxmwe

Noise Removal of Functional Near Infrared Spectroscopy Signals Using Emperical Mode Decomposition and Independent Component Analysis [chapter]

Pham Thi Kim Chi, Vo Nhut Tuan, Nguyen Hoai Thuong, Ho Thi Kieu Khanh, Hui Yu, Nguyen Duc Thang
2017 International Federation for Medical and Biological Engineering Proceedings  
ICA uses Hyvarinen's fixed-point algorithm to estimate the independent components from given multidimensional signals.  ...  However, the use of sensors attached on the human subjects during fNIRS measurement is uncomfortable for a user and is complicated for setup.  ...  The table 1 illustrates the frequencies and correlations of estimated Heart component and PPG signal of Subject 1 and Subject 2 in two minutes with 15-second time intervals The assessment on the result  ... 
doi:10.1007/978-981-10-4361-1_156 fatcat:ggyk7jo5gjflbhqhgsvu7fk4le

Time-Frequency Analysis of Non-Stationary Biological Signals with Sparse Linear Regression Based Fourier Linear Combiner

Yubo Wang, Kalyana Veluvolu
2017 Sensors  
This necessitates the usage of time-frequency decomposition methods for analyzing the subtle changes in these signals that are often connected to an underlying phenomena.  ...  The coefficients of the proposed model are then estimated by a convex optimization algorithm. The performance of the proposed method was analyzed with benchmark test signals.  ...  To handle the non-stationarity of such signals, time-frequency decomposition methods are usually employed for obtaining time-frequency mapping of such signals [4] [5] [6] [7] .  ... 
doi:10.3390/s17061386 pmid:28613239 pmcid:PMC5492605 fatcat:jsffh52sova7dmnes4s5xjx654

Robust Fisher's Test for Periodicity Detection in Noisy Biological Time Series

Miika Ahdesmaki, Harri Lahdesmaki, Olli Yli-Harja
2007 2007 IEEE International Workshop on Genomic Signal Processing and Statistics  
Periodicity detection in time series measurements is a usual application of signal processing in studying biological data.  ...  The reasons for detecting periodically behaving biological events are many, e.g. periodicity in gene expression time series could suggest cell cycle control over the gene expression.  ...  METHODS Fisher's test for the detection of hidden periodicities of unspecified frequency in time series ( [4] ) is a well known test based on the periodogram spectral estimator.  ... 
doi:10.1109/gensips.2007.4365817 fatcat:nhy5nkik2rfz7beqtk4zkz76jy

Estimation of PSD Shifts for High-Resolution Metrology of Thickness Micro-Changes with Possible Applications in Vessel Walls and Biological Membrane Characterization

Antonio Ramos, Ivonne Bazán, Carlos Negreira, Javier Brum, Tomás Gómez, Héctor Calás, Abelardo Ruiz, José Rosa
2012 Sensors  
These ultrasonic echo-pulses present rather complex time and frequency distributions making, a direct interpretation of the related tissue information, difficult, but just the spectral estimation is a  ...  of the time echo-waveforms [19, [21] [22] [23] .  ...  Signal Processing Estimators and Operators to be Applied for Thickness Measurement Techniques In this sub-section, some selected analysis tools implemented in time and frequency domains, for achieving  ... 
doi:10.3390/s121115394 pmid:23202216 pmcid:PMC3522969 fatcat:vyi2x4xfkveevoudk6y6qdkueq

Performance Evaluation Of Complex Electrical Bio-Impedance From V/I Four-Electrode Measurements

Towfeeq Fairooz, Salim Istyaq
2011 Zenodo  
First, the complex impedance is estimated by three different estimation techniques: Fourier, Sine Correlation and Digital De-convolution and then estimation errors for the magnitude, phase, reactance and  ...  resistance are calculated and analyzed for different levels of disturbances in the observations.  ...  Here in Fourier analysis method Additive White Gaussian Noise (AWGN) is added to single tone signal in time domain and then FFT is applied so as to transform it in frequency domain.  ... 
doi:10.5281/zenodo.1081888 fatcat:kywrn7uxcjf6res636ii5elak4

ANTENNA CALIBRATION METHOD FOR DIELECTRIC PROPERTY ESTIMATION OF BIOLOGICAL TISSUES AT MICROWAVE FREQUENCIES

David C. Garrett, Jeremie Bourqui, Elise C. Fear
2017 Electromagnetic Waves  
To overcome this, a method of antenna calibration has been adapted and developed for use with an antenna system designed for biomedical applications, allowing for the estimation of permittivity and conductivity  ...  We aim to estimate the average dielectric properties of centimeter-scale volumes of biological tissues.  ...  The bulk permittivity is estimated from the time necessary for the microwave signal to be transmitted through the tissue.  ... 
doi:10.2528/pier16122204 fatcat:m5m7wgsq3fhuhilmjrdntl75tm

Estimation of Biological Signal Features Indicating Riding Comfort Changes by Trail Variation

Yasuki Muto, Taiki Fuji, Yasue Mitsukura
2013 Journal of Signal Processing  
In this paper, we aim to construct an evaluation method for bicycle-riding comfort using biological signals.  ...  We analyze the EMG and the EEG to estimate the features of these biological signals and how they reflect changes in bicycle-riding comfort.  ...  This proposed method is repeated 100 times for each case.  ... 
doi:10.2299/jsp.17.143 fatcat:xi7yndtylzazba7xppssw5icsi

Study on Spectrum Estimation in Biophoton Emission Signal Analysis of Wheat Varieties

Yitao Liang, Hongxia Song, Qin Liu, Weiya Shi, Lan Li
2014 Mathematical Problems in Engineering  
To study the features of the photon emission signal, the spectrum estimation method of the photon emission signal is described for the first time.  ...  The results of power spectrum estimation deduced that the biophoton emission signal is a low frequency signal, and its power spectrum is mostly distributed in the frequency less than 0.1 Hz.  ...  spectral estimation method.  ... 
doi:10.1155/2014/606275 fatcat:trl5cu53org7hgc5nlorwlwol4

Dynamic Clustering of Gene Expression

Lingling An, R. W. Doerge
2012 ISRN Bioinformatics  
By taking advantage of techniques and theories from time frequency analysis, periodic gene expression profiles are dynamically clustered based on the assumption that different spectral frequencies characterize  ...  Unfortunately, clustering methodologies that group genes for the purpose of novel gene discovery fail to acknowledge the dynamic nature of biological processes and provide static clusters, even when the  ...  For each gene in either true class C, or estimated cluster E, consider the true time interval and estimated time interval.  ... 
doi:10.5402/2012/537217 pmid:25969750 pmcid:PMC4393063 fatcat:zd67dpdgajfv5gshtyphtoh5qa

Presenting A Combinatorial Feature To Estimate Depth Of Anesthesia

Toktam Zoughi, Reza Boostani
2010 Zenodo  
In this method, first EEG signal is decomposed into different sub-bands, then samples are squared and energy of samples sequence is constructed through each scale and time, which is normalized and finally  ...  A novel method based on energy scattering of samples in the wavelet domain is suggested to represent the basic content of electroencephalogram (EEG) signal.  ...  ACKNOWLEDGMENT The authors of this paper present their warm regards to Reza Sameni and Farid Zand for their valuable academic comments on this paper.  ... 
doi:10.5281/zenodo.1083923 fatcat:ssv3arieznh63dnaxob3dynudm

Biological Signal Processing and Analysis for Healthcare Monitoring

Yunfeng Wu, Behnaz Ghoraani
2022 Sensors  
Nowadays, portable and wireless wearable sensors have been commonly incorporated into the signal acquisition modules of healthcare monitoring systems [...]  ...  The short-time Fourier transform, wavelet transform, and time-frequency analysis based on matching pursuit decomposition can provide more details about the time-varying frequency distributions for signal  ...  The biological signal processing and analysis techniques contain the design of signal preprocessing tools for portable wearable sensors, artifact cancellation methods for signal quality improvement, nonlinear  ... 
doi:10.3390/s22145341 pmid:35891021 pmcid:PMC9319153 fatcat:6l5atf7hezf77ddzebsvhddi24

Robust Algorithm for Heart Rate (HR) Detection and Heart Rate Variability (HRV) Estimation

Z. Piotrowski, K. Różanowski
2010 Acta Physica Polonica. A  
This algorithm is dedicated for biological signal detection, electrocardiogram, in noisy environment with lot of artifacts.  ...  We present algorithm for Heart Rate detection based on Short-Term Autocorrelation Center Clipping method.  ...  Biological ECG signal is acquired with sampling frequency rate f s = 250 Hz.  ... 
doi:10.12693/aphyspola.118.131 fatcat:wedybjcmrjhoneuqk5j3527y4m

Influence Of The Sinusoidal And Gaussian Noises In The Estimation Of The Eeg Fractal Dimension

A. Accardo, M. Affinito, M. Carrozzi
1996 Zenodo  
Since biological signals are frequently affected by noise introduced both by the measuring instrumentation and by undesired biological events, the D estimation can result incorrect.  ...  Fs (about 8 times the Nyquist frequency) are requested.  ... 
doi:10.5281/zenodo.36165 fatcat:o7hu7fql65hdxfqdpwuimwsrum

Temporal scales and signal modeling in dendroclimatology

Joël Guiot
2017 Past Global Change Magazine  
No method is perfect and some of them reduce the low-frequency signal excessively, while others introduce spurious low-frequency variations.  ...  Reconstruction based on multiple proxies and process-based modeling approaches are needed to estimate the climate signal at lower frequencies. temporal scales and signal modeling in dendroclimatology Joël  ... 
doi:10.22498/pages.25.3.142 fatcat:odwesqxncfeerevnkny2phfmh4
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