Results 71 to 80 of about 70,602 (222)

On the Subelliptic Eikonal Equation

Bruno Pini Mathematical Analysis Seminar, 2017
On a bounded smooth domain, we consider the viscosity solution of the homogeneous Dirichlet problem for the eikonal equation associated with a system of Hörmander’s vector fields.
Paolo Albano
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How smooth is quantum complexity?

Journal of High Energy Physics, 2021
The “quantum complexity” of a unitary operator measures the difficulty of its construction from a set of elementary quantum gates. While the notion of quantum complexity was first introduced as a quantum generalization of the classical computational ...
Vir B. Bulchandani, S. L. Sondhi
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Liouville Integrability in a Four-Dimensional Model of the Visual Cortex

Journal of Imaging, 2021
We consider a natural extension of the Petitot–Citti–Sarti model of the primary visual cortex. In the extended model, the curvature of contours is taken into account.
Ivan Galyaev, Alexey Mashtakov
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A proof of a trace formula by Richard Melrose

Advanced Nonlinear Studies, 2023
The goal of this article is to give a new proof of the wave trace formula proved by Richard Melrose in an impressive article. This trace formula is an extension of the Chazarain-Duistermaat-Guillemin trace formula (denoted as “CDG trace formula” in this ...
Colin de Verdière Yves
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A contact covariant approach to optimal control with applications to sub-Riemannian geometry [PDF]

, 2016
We discuss contact geometry naturally related with optimal control problems (and Pontryagin Maximum Principle). We explore and expand the observations of [Ohsawa, 2015], providing simple and elegant characterizations of normal and abnormal sub-Riemannian
Jóźwikowski, Michał, Respondek, Witold   +1 more
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The rolling problem: overview and challenges

, 2012
In the present paper we give a historical account -ranging from classical to modern results- of the problem of rolling two Riemannian manifolds one on the other, with the restrictions that they cannot instantaneously slip or spin one with respect to the ...
A Agrachev, A Agrachev, A Agrachev, A Chelouah, A Marigo, A Marigo, AM Bloch, AV Borisov, Cartan, Cartan, DJ Montana, DW Stroock, E Grong, EP Hsu, F Alouges, G Bor, H Sussmann, I Zelenko, I Zelenko, IM Singer, J Zimmerman, J-M Bismut, K Hüper, K Hüper, K Nomizu, M Godoy Molina, M Godoy Molina, P Rouchon, PB Gilkey, PE Jupp, R Bryant, R Montgomery, R Murray, RW Sharpe, S Kobayashi, SA Chaplygin, SA Chaplygin, T Sakai, V Jurdjevic, V Jurdjevic, V Jurdjevic, Y Chitour, Y Chitour, Y Chitour, Z Li   +44 more
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Cortical-inspired image reconstruction via sub-Riemannian geometry and hypoelliptic diffusion

ESAIM: Proceedings and Surveys, 2018
In this paper we review several algorithms for image inpainting based on the hypoelliptic diffusion naturally associated with a mathematical model of the primary visual cortex. In particular, we present one algorithm that does not exploit the information
Boscain Ugo, Chertovskih Roman, Gauthier Jean-Paul, Prandi Dario, Remizov Alexey   +4 more
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Nilpotent Approximations of Sub-Riemannian Distances for Fast Perceptual Grouping of Blood Vessels in 2D and 3D [PDF]

, 2017
We propose an efficient approach for the grouping of local orientations (points on vessels) via nilpotent approximations of sub-Riemannian distances in the 2D and 3D roto-translation groups $SE(2)$ and $SE(3)$.
Bekkers, Erik J., Chen, Da, Portegies, Jorg M.   +2 more
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Sub-Laplacian eigenvalue bounds on sub-Riemannian manifolds [PDF]

, 2015
We study eigenvalue problems for intrinsic sub-Laplacians on regular sub-Riemannian manifolds. We prove upper bounds for sub-Laplacian eigenvalues λk of conformal sub-Riemannian metrics that are asymptotically sharp as k→+∞. For Sasakian manifolds with a
Hassannezhad, A, Kokarev, G
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A New Subject-Specific Discriminative and Multi-Scale Filter Bank Tangent Space Mapping Method for Recognition of Multiclass Motor Imagery

Frontiers in Human Neuroscience, 2021
Objective: Tangent Space Mapping (TSM) using the geometric structure of the covariance matrices is an effective method to recognize multiclass motor imagery (MI).
Fan Wu, Fan Wu, Anmin Gong, Hongyun Li, Hongyun Li, Lei Zhao, Lei Zhao, Wei Zhang, Yunfa Fu, Yunfa Fu, Yunfa Fu, Yunfa Fu   +11 more
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