Results 31 to 40 of about 808,598 (165)
Trace functions as Laplace transforms
, 2005 We study trace functions on the form $ t\to\tr f(A+tB) $ where $ f $ is a real function defined on the positive half-line, and $ A $ and $ B $ are matrices such that $ A $ is positive definite and $ B $ is positive semi-definite. If $ f $ is non-negative
Araki H. +4 more
core +1 more source
IEEE Access, 2019 Time-varying disturbances not only exist in the external delay of Markovian jump system but also may exist in the transfer rate of internal probability transfer.
Liankun Sun, Nuo Xu
doaj +1 more source
Intrinsic data depth for Hermitian positive definite matrices
, 2018 Nondegenerate covariance, correlation and spectral density matrices are necessarily symmetric or Hermitian and positive definite. The main contribution of this paper is the development of statistical data depths for collections of Hermitian positive ...
Chau, Joris +2 more
core +1 more source
On limit cycles of autonomous systems
Современная математика: Фундаментальные направленияWe consider the problem of the existence of limit cycles for autonomous systems of differential equations. We present quite elementary considerations that can be useful in discussing qualitative issues that arise in the course of ordinary differential ...
T. M. Ivanova +3 more
doaj +1 more source
Revstat Statistical Journal, 2013 This paper provides an accessible methodology for approximating the distribution of a general linear combination of non-central chi-square random variables. Attention is focused on the main application of the results, namely the distribution of positive
Hyung-Tae Ha
doaj +1 more source
Entropy, 2014 We prove a large deviation principle for a stationary Gaussian process over Rb,indexed by Ζd (for some positive integers d and b), with positive definite spectral density, andprovide an expression of the corresponding rate function in terms of the mean ...
Olivier Faugeras, James MacLaurin
doaj +1 more source
SPD Data Dictionary Learning Based on Kernel Learning and Riemannian Metric
IEEE Access, 2020 The use of regional covariance descriptors to generate feature data represented by Symmetric Positive Definite (SPD) matrices from images or videos has become increasingly common in machine learning.
Rixin Zhuang +3 more
doaj +1 more source
Extensions of positive definite functions on amenable groups
, 2008 Let $S$ be a subset of a amenable group $G$ such that $e\in S$ and $S^{-1}=S$. The main result of the paper states that if the Cayley graph of $G$ with respect to $S$ has a certain combinatorial property, then every positive definite operator-valued ...
D. Timotin +4 more
core +1 more source
Distributional boundary values of analytic functions and positive definite distributions
Nonlinear Analysis, 2015 We propose necessary and sufficient conditions for a distribution (generalized function) fof several variables to be positive definite. For this purpose, certain analytic extensions of f to tubular domains in complex space Cn are studied. The main result
Saulius Norvidas
doaj +1 more source
Continuations of Hermitian indefinite functions and corresponding canonical systems : an example [PDF]
, 2004 M. G. Krein established a close connection between the continuation problem of positive definite functions from a finite interval to the real axis and the inverse spectral problem for differential operators.
Langer, Heinz +2 more
core +1 more source