Results 91 to 100 of about 5,000 (262)

An efficient discrete Chebyshev polynomials strategy for tempered time fractional nonlinear Schrödinger problems

Journal of Advanced Research
Introduction: An interesting type of fractional derivatives that has received widespread attention in recent years is the tempered fractional derivatives. These fractional derivatives are a generalization of the well-known fractional derivatives, such as
Mohammad Hossein Heydari, Dumitru Baleanu   +1 more
doaj   +1 more source

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

Latitudinal effect on the structure of snake–prey interaction networks is mediated by snake species richness

Ecography, EarlyView.
Despite the growing number of studies on trophic networks in recent decades, there are still important gaps in our understanding of how these networks are structured across broad environmental gradients. These gaps are even greater in some groups of terrestrial vertebrates, such as snakes, requiring a cohesive synthesis of their broader trophic ...
Daniela Pinto‐Coelho, Kate P. Maia, Laura R. V. Alencar, Marcio Martins, Paulo R. Guimarães   +4 more
wiley   +1 more source

Influence of Structural and Environmental Parameters on Solar Air Collector Performance

Energy Science &Engineering, EarlyView.
Increasing air gap depth and mass flow rate significantly enhances the thermal performance of solar air collectors, with optimal performance achieved at an 8.5 cm air gap and 0.01318 kg/s mass flow rate. Air gap depth is identified as the dominant factor influencing system efficiency.
Quankun Zhu, István Farkas, János Buzas   +2 more
wiley   +1 more source

Edge‐Based Discretizations on Triangulations in Any Dimension, With Special Attention to Four‐Dimensional Space

International Journal for Numerical Methods in Fluids, EarlyView.
This article provides important geometric formulas for node‐centered, edge‐based schemes in any number of dimensions. These formulas are noteworthy, as they do not require the explicit formation of dual regions. We prove several key geometric results, with a particular focus on the four‐dimensional case, due to potential space‐time applications ...
Nicholas Tufillaro, David M. Williams, Hiroaki Nishikawa   +2 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

Stability Conditions in Multiple-Input Multiple-Output Systems

Axioms
This paper investigates the stabilization of unstable third-order Multiple-Input Multiple-Output (MIMO) systems whose interaction structure is described by a doubly stochastic combined matrix, also known as the Relative Gain Array (RGA).
Macarena Boix, Begoña Cantó
doaj   +1 more source

Employing the Moving Least‐Squares Aided Finite Element Method to Study Heat Transfer Phenomenon in Closed‐Cell Polymeric Foam

International Journal for Numerical Methods in Fluids, EarlyView.
Employing the moving least‐squares aided finite element method (MLS‐FEM) allows detailed thermal analysis in complex porous structures, such as polymeric foams, where the conductive heat transfer mechanism governs in the solid matrix and the convective mechanism dominates within the gas‐filled voids.
Mehdi Mostafaiyan, Sven Wiessner, Andreas Leuteritz   +2 more
wiley   +1 more source

Estimation and Global Stability Analysis of PDAEs with Singular Time Derivative Matrix and Wetland Conservation Application

Discrete Dynamics in Nature and Society, 2016
Some partial differential algebraic equations (PDAEs) system with singular time derivative matrices is analyzed. First, by PDE spectrum theory, this system is formulated as infinite-dimensional singular systems. Second, the state space and its properties
Yushan Jiang, Qingling Zhang
doaj   +1 more source

Artificial Intelligence–Driven MRI for Cervical Nodal Metastasis Detection in Oral Squamous Cell Carcinoma: A Hierarchical Meta‐Analysis of Diagnostic Accuracy

Head &Neck, EarlyView.
ABSTRACT Background Artificial intelligence (AI) applied to magnetic resonance imaging (MRI) may improve detection of cervical lymph node metastases in oral squamous cell carcinoma (OSCC) but is heterogeneous. Methods A systematic review identified observational studies (from 2000) evaluating AI‐based MRI in adults with histopathologically confirmed ...
José Evando da Silva‐Filho, Renata Roque Ribeiro, André Wescley Oliveira de Aguiar, Caio Marques Silva, Daniela Pita de Melo, Karuza Maria Alves Pereira, Danielle Frota de Albuquerque, Fábio Wildson Gurgel Costa, Eduardo Diogo Gurgel‐Filho   +8 more
wiley   +1 more source