Results 51 to 60 of about 284 (125)
Efficient Tensor Completion Algorithms for Highly Oscillatory Operators
ABSTRACT We address the problem of recovering highly oscillatory operators, represented as nĂn$$ n\times n $$ matrices with a fixed set of observed entries. Given that these matrices can be well compressed by butterfly matrix decomposition of L=đȘ(logn) levels requiring only O(nlogn)$$ O\left(n\log n\right) $$ degrees of freedom, we propose a novel ...
Navjot Singh +3 more
wiley +1 more source
FiniteâBlock Polynomial and Volterra Structure in Reservoir Computing
ABSTRACT Reservoir computing is analyzed through the algebraic structure generated by finiteâwidth reservoirs on fixed input blocks. For linear and quadratic logistic activations, the induced inputâtoâstate map admits an exact finite Volterra representation, yielding an explicit characterization of the associated hypothesis class.
Alfio BorzĂŹ
wiley +1 more source
Bidiagonal Decompositions and HighâAccuracy Computations for Newton Collocation Matrices
ABSTRACT We consider a class of collocation matrices A$$ A $$ associated with the Newton basis of the space of polynomials of degree at most n$$ n $$, evaluated at a set of l+1â„n+1$$ l+1\ge n+1 $$ nodes. In the most general setting, we allow n$$ n $$ of these nodes to either coincide with or differ from those defining the Newton basis.
E. Mainar, A. Marco, B. Rubio, R. Viaña
wiley +1 more source
Randomized Algorithms for Streaming LowâRank Approximation in Tree Tensor Network Format
ABSTRACT In this work, we present the tree tensor network Nyström (TTNN), an algorithm that extends recent research on streamable tensor approximation, such as for Tucker and tensorâtrain formats, to the more general tree tensor network format, enabling a unified treatment of various existing methods.
Alberto Bucci, Gianfranco Verzella
wiley +1 more source
Bianchi I Spacetimes in f(Q)âGravity
ABSTRACT The Kasner spacetimes are exact solutions that are selfâsimilar and of significant interest because they can describe the dynamic evolution of kinematic variables near the singularity of the Mixmaster universe. The chaotic behavior of the Mixmaster universe is related to the Kasner relations.
Andronikos Paliathanasis, Genly Leon
wiley +1 more source
ABSTRACT We apply the boundaryâonly isothermal formulation of finiteâdistance weak gravitational deflection to regular black holes, blackâbounces, traversable wormholes, nonâasymptotically flat backgrounds, and static quadrupolar spacetimes. The methodological advance is not a new value for a known bending angle.
Reggie C. Pantig, Ali ĂvgĂŒn
wiley +1 more source
Intrinsic Shape LDA With Application to Body Human Shapes Classification
ABSTRACT Advancements in 3D scanning and cloud infrastructure enable the acquisition and analysis of highâdensity body surface datasets. In this work, we propose a novel methodology that extends linear discriminant analysis (LDA) to Kendall's shape space for the classification of 3D objects, specifically human body shapes.
Jorge Valero +3 more
wiley +1 more source
Uncovering hidden bias in neutron diffraction residual strain measurements
This work demonstrates that diffractionâbased residual strain calculations and uncertainty estimates depend on how grain populations are subâsampled, with important implications for interpreting residual stresses in heterogeneous materials with fineâscale microstructure and strain gradients.When calculating residual strain via neutron or Xâray ...
Cole Franz +4 more
wiley +1 more source
A MatrixâFree, Scalable, and Robust Implicit Material Point Method
ABSTRACT An implicit material point method is presented using a new dynamic relaxation solver, allowing for a simple and efficient quasiâstatic formulation that may be readily implemented in existing explicitâdynamic codes. The use of dynamic relaxation and aggregation is shown to produce an extremely robust material point method scheme, with good ...
Sam J. V. Sutcliffe +5 more
wiley +1 more source
Surface and Boundary Corrections in Peridynamics Using Optimized Nodal Influence Weights
ABSTRACT Peridynamics (PD), similarly to some other nonlocal continuum theories, exhibits truncated interaction horizons near free surfaces, cracks, and voids in bounded domains. This loss of neighbors causes artificial surface effects and inconsistencies in the derivative and energy operators that persist under discretization refinement, limiting PD ...
Arman Shojaei +5 more
wiley +1 more source

