Results 21 to 30 of about 1,130,790 (239)
Applied Sciences, 2023 Electroencephalography (EEG) signals have diverse applications in brain-computer interfaces (BCIs), neurological condition diagnoses, and emotion recognition across healthcare, education, and entertainment domains.
Zubaidah Al-Mashhadani +4 more
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Applied Sciences, 2020 The electroencephalogram (EEG) signal in the brain–computer interface (BCI) has suffered great cross-subject variability. The BCI system needs to be retrained before each time it is used, which is a waste of resources and time.
Feng Li +5 more
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Background field method for nonlinear sigma models in nonrelativistic string theory
Journal of High Energy Physics, 2020 We continue the study of nonrelativistic string theory in background fields. Nonrelativistic string theory is described by a nonlinear sigma model that maps a relativistic worldsheet to a non-Lorentzian and non-Riemannian target space geometry, which is ...
Ziqi Yan, Matthew Yu
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Riemannian Geometry of Symmetric Positive Definite Matrices via Cholesky Decomposition [PDF]
SIAM Journal on Matrix Analysis and Applications, 2019 We present a new Riemannian metric, termed Log-Cholesky metric, on the manifold of symmetric positive definite (SPD) matrices via Cholesky decomposition. We first construct a Lie group structure and a bi-invariant metric on Cholesky space, the collection
Zhenhua Lin
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A Generalized Bochner Technique and Its Application to the Study of Conformal Mappings
Axioms, 2021 This article is devoted to geometrical aspects of conformal mappings of complete Riemannian and Kählerian manifolds and uses the Bochner technique, one of the oldest and most important techniques in modern differential geometry. A feature of this article
Vladimir Rovenski +2 more
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On some conformally einstein manifolds of dimension four [PDF]
ریاضی و جامعه, 2022 We study an important family of four-dimensional pseudo-Riemannian manifolds, i.e. generalized symmetric spaces, in terms of conformal geometry. Generalized symmetric spaces were introduced by geometers as an extension of symmetric spaces, and a detailed
Amirhesam Zaeim +2 more
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The Geometry of Riemannian Spaces [PDF]
Transactions of the American Mathematical Society, 1934 The primary purpose of this paper is to expose, in as simple and clear a form as is possible, the fundamentals of the geometric structure of a Riemannian space. It is a general truth that the methods which pierce most deeply into the heart of a geometric theory are invariant methods, that is, methods which are independent of the choice of the ...
openaire +2 more sources
On Cartan torsion of 4-dimensional Finsler manifolds [PDF]
Journal of HyperstructuresThere are several non-Riemannian curvatures in Finsler geometry which show the complexity of Finsler geometry with respect to Riemannian geometry. Amon these quantities, the Cartan and mean Cartan torsion have very important and brilliant positions.
Akbar Tayebi
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String Theory and Non-Riemannian Geometry.
Physical Review Letters, 2020 The O(D,D) covariant generalized metric, postulated as a truly fundamental variable, can describe novel geometries where the notion of Riemannian metric ceases to exist.
Jeong-Hyuck Park, S. Sugimoto
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Geometry without topology as a new conception of geometry
International Journal of Mathematics and Mathematical Sciences, 2002 A geometric conception is a method of a geometry construction. The Riemannian geometric conception and a new T-geometric one are considered. T-geometry is built only on the basis of information included in the metric (distance between two points).
Yuri A. Rylov
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