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Block FIR decision-feedback equalizers for filterbank precoded transmissions with blind channel estimation capabilities

A. Stamoulis, G.B. Giannakis, A. Scaglione
2001 IEEE Transactions on Communications  
Closed-form expressions are derived for the FIR linear or DF filterbank receivers corresponding to varying amounts of transmission redundancy.  ...  In block transmission systems, transmitter-induced redundancy using finite-impulse response (FIR) filterbanks can be used to suppress intersymbol interference and equalize FIR channels irrespective of  ...  In this section, we explore how transmit-redundancy can be used for channel estimation.  ... 
doi:10.1109/26.898252 fatcat:2aunasfne5b4bjwg2sdp57zp5u

Truncated Gaussian-Mixture Variational AutoEncoder [article]

Qingyu Zhao, Nicolas Honnorat, Ehsan Adeli, Kilian M. Pohl
2021 arXiv   pre-print
Recently, several studies have proposed to use VAE for unsupervised clustering by using mixture models to capture the multi-modal structure of latent representations.  ...  Variation Autoencoder (VAE) has become a powerful tool in modeling the non-linear generative process of data from a low-dimensional latent space.  ...  For example, each x i represents a dynamic connectivity pattern, i.e., the upper triangular part of an ROI-to-ROI correlation matrix derived from the rs-fMRI time series at a given sliding window [2]  ... 
arXiv:1902.03717v3 fatcat:74qmq5dpr5dxrn5eqtqhx2sfdi

Theoretical and experimental assessments of accuracy of nonorthogonal mems sensor arrays

Olha Sushchenko, Yurii Bezkorovainyi, Nataliia Novytska
2018 Eastern-European Journal of Enterprise Technologies  
Complex network approach for recurrence analysis of time series / Marwan N., Donges J. F., Zou Y., Donner R.  ...  This table includes data about values of traces of the correlation matrices of errors for different nonorthogonal redundant configurations in different situations of sensor failures.  ...  Table 6 Table of directional cosines for the configuration using the triangular pyramid as a constructive unit The table of directional cosines (numerical data) for the nonorthogonal redundant configuration  ... 
doi:10.15587/1729-4061.2018.131945 fatcat:4rxpvff7pzcurdbzlkaxwxodna

Nonparametric estimation of large covariance matrices of longitudinal data

W. B. Wu
2003 Biometrika  
Our framework is similar to the use of increasing-order autoregressive models in approximating the covariance matrix or the spectrum of a stationary time series.  ...  A simulation study reveals the advantage of nonparametric covariance estimator over the sample covariance matrix for large covariance matrices.  ...  The use of (15) in testing whether or not certain entries of T are zero is crucial for simplifying the structure of T and is closely related to the use of a (partial) correlogram in identifying time series  ... 
doi:10.1093/biomet/90.4.831 fatcat:luabekkleja4rk6cy3iynwc7hm

Multi-Scale Factor Analysis of High-Dimensional Brain Signals [article]

Chee-Ming Ting, Hernando Ombao, Sh-Hussain Salleh
2017 arXiv   pre-print
The correlation matrix for all nodes in the network are approximated by lower-dimensional sub-structures derived from the cluster-specific factors.  ...  The proposed novel approach is applied to estimate brain connectivity networks using functional magnetic resonance imaging (fMRI) data.  ...  Fig. 5 shows the correlation matrix, Σ ff (absolute-valued for comparison with the non-negative RVs) of the factor time series over the entire brain, constructed form sub-blocks of correlation matrices  ... 
arXiv:1705.06502v1 fatcat:rcgpvwqzf5ezheb26bwz3nnrli

Phase Estimation for Distributed Scatterers in InSAR Stacks Using Integer Least Squares Estimation

Sami Samiei-Esfahany, Joana Esteves Martins, Freek van Leijen, Ramon F. Hanssen
2016 IEEE Transactions on Geoscience and Remote Sensing  
We model the SM-phase estimation problem in a linear form by introducing additional integer ambiguities and use a bootstrap estimator for joint estimation of SM-phases and the integer unknowns.  ...  The key step in these algorithms is to optimally estimate single-master (SM) wrapped phases for each pixel from all possible interferometric combinations, preserving useful information and filtering noise  ...  Mahapatra for editing this paper.  ... 
doi:10.1109/tgrs.2016.2566604 fatcat:3utey3fy3bcl3pacrpplhysu7i

Non-orthogonal joint block diagonalization based on the LU or QR factorizations for convolutive blind source separation

Lei Zhang, Yueyun Cao, Zichun Yang, Lei Weng
2017 Journal of Vibroengineering  
Using Jacobi-type matrices we can replace high dimensional minimization problems with a sequence of simple one-dimensional problems.  ...  One kind of prevailing and representative approaches for overcoming these difficulties is joint block diagonalization (JBD) method.  ...  Research on the identification of cross-coupling mechanical vibration sources of warship based on transfer path analysis.  ... 
doi:10.21595/jve.2017.18039 fatcat:6t7w6deigjcttjjmrzwumstuda

Optimizing Sparse Matrix-Multiple Vectors Multiplication for Nuclear Configuration Interaction Calculations

Hasan Metin Aktulga, Aydin Buluc, Samuel Williams, Chao Yang
2014 2014 IEEE 28th International Parallel and Distributed Processing Symposium  
We develop a performance model that allows us to understand and estimate the performance characteristics of our SpMM kernel implementations, and demonstrate the efficiency of our implementation on a series  ...  In the Many-body Fermion Dynamics for nuclei (MFDn) code, a block eigensolver is used for this purpose.  ...  We demonstrate the efficiency of our implementation with respect to existing methods for the regular SpMM operation and the transpose operation on a series of real-world matrices extracted from MFDn.  ... 
doi:10.1109/ipdps.2014.125 dblp:conf/ipps/AktulgaBWY14 fatcat:st5jejogzfdatinzbmd2jy3vem

Untangling the relatedness among correlations, Part II: Inter-subject correlation group analysis through linear mixed-effects modeling

Gang Chen, Paul A. Taylor, Yong-Wook Shin, Richard C. Reynolds, Robert W. Cox
2017 NeuroImage  
It has been argued that naturalistic conditions in FMRI studies provide a useful paradigm for investigating perception and cognition through a synchronization measure, inter-subject correlation (ISC).  ...  of real data to show that the methodologies adopted in the literature do not have the proper control for false positives.  ...  The research and writing of the paper were supported by the NIMH and NINDS Intramural Research Programs (ZICMH002888) of the NIH/HHS, USA, and by a grant (2012-0230) from the Asan Institute for Life Sciences  ... 
doi:10.1016/j.neuroimage.2016.08.029 pmid:27751943 pmcid:PMC5303634 fatcat:zaogcpkb5nclbnpez4gqy24mdy

Incorporating Stakeholder Knowledge into a Complex Stock Assessment Model: The Case of Eel Recruitment

Hilaire Drouineau, Marie Vanacker, Estibaliz Diaz, Maria Mateo, Maria Korta, Carlos Antunes, Carlos Fernández Delgado, Isabel Domingos, Lluis Zamora, Laurent Beaulaton, Patrick Lambert, Cédric Briand
2021 Water  
The GEREM model has been proposed as a tool for estimating recruitment, but its complexity, which is essential for addressing the characteristics of the species, makes it difficult to understand and accept  ...  Through the use of various questionnaires, stakeholders were involved in two important choices for the model (zone definition and prior construction).  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/w13091136 fatcat:manqg3cx6vdstmmndcpzzic6l4

Transmitter redundancy for blind estimation and equalization of time- and frequency-selective channels

C. Tepedelenlioglu, G.B. Giannakis
2000 IEEE Transactions on Signal Processing  
Relying on transmitter-induced redundancy, we propose novel channel estimation and symbol recovery approaches for blind identification and equalization of time-and frequency-selective channels, where the  ...  His general interests lie in the areas of signal processing and communications, estimation and detection theory, time-series analysis, and system identification-subjects on which he published more than  ...  Scaglione for her comments.  ... 
doi:10.1109/78.847788 fatcat:ge5fodagp5fnjc65wjiqchygm4

Comparing Cyclicity Analysis With Pre-established Functional Connectivity Methods to Identify Individuals and Subject Groups Using Resting State fMRI

Somayeh Shahsavarani, Ivan T. Abraham, Benjamin J. Zimmerman, Yuliy M. Baryshnikov, Fatima T. Husain
2020 Frontiers in Computational Neuroscience  
To use information related to temporal ordering, cyclicity analysis has been introduced to capture pairwise interactions between multiple time series.  ...  For both patient and control groups, we found that the features generated by cyclicity and correlation (zero-lag and lagged) analyses were more reliable than the features generated by dynamic time warping  ...  With GSR The time series were normalized using their quadratic variation.LM, Lead Matrices; CM, Zero-lag Correlation Matrices; LCM, Lagged Correlation Matrices; DM, Dynamic Time Warping Matrices; BPF,Band-Pass  ... 
doi:10.3389/fncom.2019.00094 pmid:32038211 pmcid:PMC6984040 fatcat:diwhjsmqnjhhhiqd5ajebm5br4

Computationally Efficient Approximations for Matrix-based Renyi's Entropy [article]

Tieliang Gong and Yuxin Dong and Shujian Yu and Bo Dong
2022 arXiv   pre-print
The recently developed matrix based Renyi's entropy enables measurement of information in data simply using the eigenspectrum of symmetric positive semi definite (PSD) matrices in reproducing kernel Hilbert  ...  space, without estimation of the underlying data distribution.  ...  We use the binomial series to build our algorithm, which is the Taylor series for function: (1 + A) α = ∞ j=0 α j A n . ( 10 ) Binomial series converge absolutely for symmetric matrices A with eigenvalues  ... 
arXiv:2112.13720v3 fatcat:h3r52wrpkngczeiivcfq7t4mje

Multivariate Seasonal Adjustment, Economic Identities, and Seasonal Taxonomy

Tucker McElroy
2017 Journal of business & economic statistics  
This paper extends these latter efforts by exploring the statistical modeling of seasonality jointly across multiple time series, using latent dynamic factor models fitted using maximum likelihood estimation  ...  time series.  ...  To obtain a better understanding of the correlation patterns, we display the partial correlation matrices L for the various models.  ... 
doi:10.1080/07350015.2015.1123159 fatcat:gxc3r4cqorf47oors6q4zznbp4

Dynamic Functional Connectivity as a complex random walk: definitions and the dFCwalk toolbox

Lucas M. Arbabyazd, Diego Lombardo, Olivier Blin, Mira Didic, Demian Battaglia, Viktor Jirsa
2020 MethodsX  
•We have developed a framework to describe the dynamics of Functional Connectivity (dFC) estimated from brain activity time-series as a complex random walk in the space of possible functional networks.  ...  non-neural time-series.  ...  Acknowledgements DB acknowledges support from the Mission for Interdisciplinarity of the CNRS (Infiniti program 2017-2018, "BrainTime") and from the EU Innovative Training Network "i-CONN" (H2020 ITN 859937  ... 
doi:10.1016/j.mex.2020.101168 pmid:33344179 pmcid:PMC7736993 fatcat:p54zwqfrkvhkdjdbakehejqv2y
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