Results 51 to 60 of about 21,724 (205)

On a continuation approach in Tikhonov regularization and its application in piecewise-constant parameter identification

, 2013
We present a new approach to convexification of the Tikhonov regularization using a continuation method strategy. We embed the original minimization problem into a one-parameter family of minimization problems.
Melicher, Valdemar, Vrabel, Vladimir
core   +1 more source

Sleep Alters the Velocity of Physiological Brain Pulsations in Humans

Advanced Science, EarlyView.
Sleep alters I/CSF oscillatory flow, driven by increased respiratory (29%) and vasomotor pulsation (21%) velocities, while cardiovascular pulsations decreased by (22%). Velocity is quantified using optical flow analysis of MREG data. Spectral power increases alongside these pulsations (spatial correlation, r = 0.35 and r = 0.39, respectively ...
Ahmed Elabasy, Heta Helakari, Tommi Väyrynen, Zalán Rajna, Niko Huotari, Lauri Raitamaa, Ville Isokoski, Matti Järvelä, Mika Kaakinen, Johanna Piispala, Mika Kallio, Vesa Korhonen, Tapio Seppänen, Vesa Kiviniemi   +13 more
wiley   +1 more source

Particle swarm optimization method for parameter selecting in Tikhonov regularization method for solving inverse problems

e-Prime: Advances in Electrical Engineering, Electronics and Energy
In this article the Tikhonov method used as a regularization technique for solving the inverse problem liner operator equation of the first kind with noisy and noise-free data. We also provide the Tikhonov method's essential analysis for tackling inverse
H.K. Al-Mahdawi, A.S. Alhumaima
doaj   +1 more source

Spatially Adaptive Tensor Total Variation-Tikhonov Model for Depth Image Super Resolution

IEEE Access, 2017
Depth images play an important role in 3-D applications. However, due to the limitation of depth acquisition equipment, the acquired depth images are usually in limited resolution. In this paper, a spatially adaptive tensor total variation-Tikhonov model
Gang Zhong, Sen Xiang, Peng Zhou, Li Yu
doaj   +1 more source

Uniform Penalty inversion of two-dimensional NMR Relaxation data

, 2016
The inversion of two-dimensional NMR data is an ill-posed problem related to the numerical computation of the inverse Laplace transform. In this paper we present the 2DUPEN algorithm that extends the Uniform Penalty (UPEN) algorithm [Borgia, Brown ...
Bortolotti, V., Brown, R. J. S., Fantazzini, P., Landi, G., Zama, F.   +4 more
core   +1 more source

Structural Eigenmodes of the Brain to Improve the Source Localization of EEG: Application to Epileptiform Activity

Advanced Science, EarlyView.
Geometry and connectivity are complementary structures, which have demonstrated their ability to represent the brain's functional activity. This study evaluates geometric and connectome eigenmodes as biologically informed constraints for EEG source localization.
Pok Him Siu, Philippa J. Karoly, Sina Mansour L., Artemio Soto‐Breceda, Levin Kuhlmann, Mark J. Cook, David B. Grayden   +6 more
wiley   +1 more source

Neural Fields for Highly Accelerated 2D Cine Phase Contrast MRI

Advanced Science, EarlyView.
ABSTRACT 2D cine phase contrast (CPC) MRI provides quantitative information on blood velocity and flow within the human vasculature. However, data acquisition is time‐consuming, motivating the reconstruction of the velocity field from undersampled measurements to reduce scan times. In this work, neural fields are proposed as a continuous spatiotemporal
Pablo Arratia, Martin J. Graves, Mary McLean, Carolin Pirkl, Carola‐Bibiane Schönlieb, Timo Schirmer, Florian Wiesinger, Matthias J. Ehrhardt   +7 more
wiley   +1 more source

A Threshold Regularization Method for Inverse Problems [PDF]

, 2011
A number of regularization methods for discrete inverse problems consist in considering weighted versions of the usual least square solution. However, these so-called filter methods are generally restricted to monotonic transformations, e.g. the Tikhonov
Rochet, Paul
core   +3 more sources

Adaptive complexity regularization for linear inverse problems

, 2008
We tackle the problem of building adaptive estimation procedures for ill-posed inverse problems. For general regularization methods depending on tuning parameters, we construct a penalized method that selects the optimal smoothing sequence without prior ...
Loubes, Jean-Michel, Ludeña, Carenne
core   +1 more source

Scalable Platform Enabling Reservoir Computing With Nanoporous Oxide Memristors for Image Recognition and Time Series Prediction

Advanced Intelligent Systems, EarlyView.
The approach of physical in materia computing incorporates parallel computing within the medium itself. A scalable and energy‐efficient, oxide‐based computational platform is realized in form of a nanoporous network of volatile niobium oxide memristors sandwiched between top and bottom metallic electrodes, and then tested for prediction and ...
Joshua Donald, Ben A. Johnson, Amir Mehrnejat, Alex Gabbitas, Arthur G. T. Coveney, Alexander G. Balanov, Sergey Savel’ev, Pavel Borisov   +7 more
wiley   +1 more source