Results 101 to 110 of about 1,042 (247)

Stochastic Gradient Descent in High Dimensions for Multi‐Spiked Tensor PCA

Communications on Pure and Applied Mathematics, EarlyView.
ABSTRACT We study the high‐dimensional dynamics of online stochastic gradient descent (SGD) for the multi‐spiked tensor model. This multi‐index model arises from the tensor principal component analysis (PCA) problem with multiple spikes, where the goal is to estimate the unknown signal vectors within the N$N$‐dimensional unit sphere through maximum ...
Gérard Ben Arous, Cédric Gerbelot, Vanessa Piccolo   +2 more
wiley   +1 more source

Invariant Subspace Method and Fractional Modified Kuramoto-Sivashinsky Equation

, 2015
In this paper, the invariant subspace method is applied to the time fractional modified Kuramoto-Sivashinsky partial differential equation. The obtained reduced system of nonlinear ordinary fractional equations is solved by the Laplace transform method and with using of some useful properties of Mittag-Leffler function.
Ouhadan, A., Kinani, E. H. El
openaire   +2 more sources

Random finite element analysis on ground subsidence caused by tunnel excavation in karst regions with spatial variable soil

Deep Underground Science and Engineering, EarlyView.
This study investigates ground subsidence during tunnel excavation in karst areas, highlighting the combined effects of karst cave proximity, cave size, and soil spatial variability. Findings suggest that shorter cave distances and larger cave sizes increase subsidence variability, and a modified Peck formula is proposed for more accurate subsidence ...
Zhenghong Su, Yong Fu, Miaomiao Sun, Kailin Ding, Ying Zhao   +4 more
wiley   +1 more source

Spectral-Spatial Ensemble Low-Rank Domain Adaptation for Hyperspectral Image Classification

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
Domain adaptation has been proven effective for addressing cross-domain hyperspectral image (HSI) classification, especially when the target domain has no labeled samples.
Xue Zhang, Guoguo Yang, Hongjun Su, Yiping Chen, Zhaohui Xue, Qian Du   +5 more
doaj   +1 more source

Invariant subspace, determinant and characteristic polynomials

, 2007
Making use of an elementary fact on invariant subspace and determinant of a linear map and the method of algebraic identities, we obtain a factorization formula for a general characteristic polynomial of a matrix.
Yaokun Wu, Wu, Yaokun
core   +1 more source

TAMNet: Temporal and adaptive‐frequency network with MixStyle for cross‐region oil and fluid production forecasting

Deep Underground Science and Engineering, EarlyView.
This paper presents temporal and adaptive‐frequency network with MixStyle (TAMNet), a deep time‐series modeling framework for accurate and robust multi‐well oil productivity forecasting. TAMNet integrates transformer and long short‐term memory architectures to capture both short‐ and long‐term temporal dependencies, enhanced by a temporal gate unit ...
Chunxi Yang, Leifeng Meng, Qinghu Fan, Ziang Guo, Ting Bao, Pingdong Zhong, Fulin Luo   +6 more
wiley   +1 more source

Subspace Acceleration for Efficient Nonlinear Water Wave Simulation

International Journal for Numerical Methods in Fluids, EarlyView.
We introduce an exponentially weighted subspace acceleration technique to reduce GMRES iterations for solving the Poisson equation with time‐dependent coefficients in nonlinear, dispersive free‐surface flows governed by the incompressible Navier‐Stokes equations. The method significantly reduces memory requirements and computational complexity compared
Rasmus Kleist Hørlyck Sørensen, Margherita Guido, Allan Peter Engsig‐Karup, Daniel Kressner   +3 more
wiley   +1 more source

Invariant co-ordinate selection

, 2009
A general method for exploring multivariate data by comparing different estimates of multivariate scatter is presented. The method is based on the eigenvalue-eigenvector decomposition of one scatter matrix relative to another.
Oja, Hannu, Lutz Dümbgen, Dümbgen, Lutz, David E. Tyler, Frank Critchley, Hannu Oja, Critchley, Frank, Paindaveine, Davy, Tyler, David E.   +8 more
core   +1 more source

Dopaminergic novelty detection and theta oscillations: Virtual reality‐based adaptive interventions for cognitive enhancement in aging

Ibrain, EarlyView.
Aging‐related cognitive decline is associated with reduced dopaminergic signaling and disrupted theta oscillations, which together impair novelty detection and memory formation. This review shows how VR environments can be used to deliver adaptive, novelty‐rich stimuli that engage dopaminergic circuits and entrain theta rhythms, thereby enhancing ...
Abraham Olufemi Asuku, Ayodeji Johnson Ajibare   +1 more
wiley   +1 more source

Independent Subspace Analysis of the Sea Surface Temperature Variability: Non-Gaussian Sources and Sensitivity to Sampling and Dimensionality

Complexity, 2017
We propose an expansion of multivariate time-series data into maximally independent source subspaces. The search is made among rotations of prewhitened data which maximize non-Gaussianity of candidate sources.
Carlos A. L. Pires, Abdel Hannachi
doaj   +1 more source