Results 61 to 70 of about 341,424 (240)
Compact Manifolds With Unbounded Nilpotent Fundamental Groups and Positive Ricci Curvature
Communications on Pure and Applied Mathematics, EarlyView.ABSTRACT It follows from the work of Kapovitch and Wilking that a closed manifold with nonnegative Ricci curvature has a uniformly almost nilpotent fundamental group. Leftover questions and conjectures, have asked if in this context the fundamental group is actually uniformly almost abelian. The main goal of this work is to construct examples (Mk9,gk)$(
Elia Bruè, Aaron Naber, Daniele Semola
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A note on the relationship between rational and trigonometric solutions of the WDVV equations [PDF]
, 2007 Legendre transformations provide a natural symmetry on the space of solutions to the WDVV equations, and more specifically, between different Frobenius manifolds.
Riley, A., Strachan, I.A.B.
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Bayesian Multivariate Two‐Stage Volatility‐Return Models (MTS‐VR)
Journal of Forecasting, EarlyView.ABSTRACT This paper develops a class of models to capture the joint dynamics of asset returns and multivariate volatility. Owing to its two‐stage construction, this class is referred to as the multivariate two‐stage volatility‐return (MTS‐VR) model.
Zhenglyu Huang +2 more
wiley +1 more source
Catalan Bounds for Symmetric Strength‐Two Orthogonal Arrays
Journal of Combinatorial Designs, EarlyView.ABSTRACT A Hamming shell construction is a two‐level array obtained by taking every binary vector of a given Hamming weight a prescribed number of times, for each weight in turn. Such arrays are invariant under all permutations of the factors, and they are strength‐two orthogonal arrays exactly when the multiplicities satisfy three linear constraints ...
Ruwan C. Karunanayaka
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Open Computer Science, 2020 The problem of maximizing a linear function with linear and quadratic constraints is considered. The solution of the problem is obtained in a constructive form using the Lagrange function and the optimality conditions.
Gorelik Victor, Zolotova Tatiana
doaj +1 more source
Journal of Intelligent Medicine, EarlyView.Abstract Simultaneous electroencephalography (EEG) recording during transcranial alternating current stimulation (tACS) is strongly contaminated by stimulation artifacts, limiting direct assessment of neural activity. Steady‐state visual evoked potentials (SSVEPs) provide frequency‐specific and phase‐locked responses, making them suitable for ...
Hongzuo Chu +5 more
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On the Frobenius norm of commutator of Cauchy-Toeplitz matrix and exchange matrix
, 2023 Matrix commutator and anticommutator play an important role in mathematics, mathematical physic, and quantum physic. The commutator and anticommutator of two n × n complex matrices A and B are defined by [A,B] = AB − BA and (A,B) = AB + BA, respectively.
Bahşi, Mustafa, Solak, Süleyman
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Invariance Properties and Measurement of Correlation Between Two Propagating or Evanescent Waves
Laser &Photonics Reviews, EarlyView.This work analyses the strength of correlation between two propagating or evanescent plane waves generally expressed in different frames. Interferometric and nanoscattering‐based methods, respectively, are demonstrated for their measurement. The results show that the applied measure of correlation remains invariant under unitary polarization ...
Zhen Dong +5 more
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Markov‐Associated Quadratic Stochastic Families and the Susceptible‐Infected‐Recovered (SIR) Model
Mathematical Methods in the Applied Sciences, EarlyView.ABSTRACT We introduce a Markov‐associated construction for quadratic stochastic families generated by a symmetric cubic stochastic matrix and a finite‐state homogeneous Markov semigroup. The constructed family is not assumed to be a classical quadratic stochastic process of type (A)$$ (A) $$ or type (B)$$ (B) $$; rather, it is a Markov‐associated ...
Taimun Qaisar +3 more
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Magnetic Resonance in Medicine, EarlyView.ABSTRACT Purpose Transmit (B1+) and receive (B1−) sensitivities of parallel‐transmit/receive RF array are a prerequisite for modern ultra‐high‐field MRI. Their accurate mapping remains challenging for coils with high transmit dynamic range, particularly in regions with low combined‐mode B1+ magnitude, where standard reconstruction is impaired by noise.
Natalia Dudysheva +5 more
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