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Positive semidefinite zero forcing
Linear Algebra and its Applications, 2013 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Ekstrand, Jason +13 more
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Higher Order Positive Semidefinite Diffusion Tensor Imaging [PDF]
SIAM Journal on Imaging Sciences, 2010 Due to the well-known limitations of diffusion tensor imaging, high angular resolution diffusion imaging (HARDI) is used to characterize non-Gaussian diffusion processes. One approach to analyzing HARDI data is to model the apparent diffusion coefficient (ADC) with higher order diffusion tensors. The diffusivity function is positive semidefinite.
Qi, L, Yu, G, Wu, EX
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Throttling positive semidefinite zero forcing propagation time on graphs [PDF]
, 2018 Zero forcing is a process on a graph that colors vertices blue by starting with some of the vertices blue and applying a color change rule. Throttling minimizes the sum of the size of the initial blue vertex set and the number of the time steps needed to
Carlson, Joshua +7 more
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Conic approach to quantum graph parameters using linear optimization over the completely positive semidefinite cone [PDF]
, 2015 We investigate the completely positive semidefinite cone $\mathcal{CS}_+^n$, a new matrix cone consisting of all $n\times n$ matrices that admit a Gram representation by positive semidefinite matrices (of any size).
Laurent, Monique, Piovesan, Teresa
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A trace bound for integer-diagonal positive semidefinite matrices
Special Matrices, 2020 We prove that an n-by-n complex positive semidefinite matrix of rank r whose graph is connected, whose diagonal entries are integers, and whose non-zero off-diagonal entries have modulus at least one, has trace at least n + r − 1.
Mitchell Lon
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Fischer Type Log-Majorization of Singular Values on Partitioned Positive Semidefinite Matrices
Journal of Function Spaces, 2021 In this paper, we establish a Fischer type log-majorization of singular values on partitioned positive semidefinite matrices, which generalizes the classical Fischer's inequality. Meanwhile, some related and new inequalities are also obtained.
Benju Wang, Yun Zhang
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Trace inequalities for positive semidefinite matrices
Discussiones Mathematicae - General Algebra and Applications, 2017 Certain trace inequalities for positive definite matrices are generalized for positive semidefinite matrices using the notion of the group generalized inverse.
Choudhury Projesh Nath, Sivakumar K.C.
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On the closure of the completely positive semidefinite cone and linear approximations to quantum colorings [PDF]
, 2015 We investigate structural properties of the completely positive semidefinite cone $\mathcal{CS}_+^n$, consisting of all the $n \times n$ symmetric matrices that admit a Gram representation by positive semidefinite matrices of any size. This cone has been
Burgdorf, Sabine +2 more
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Hilbert’s 17th problem in free skew fields
Forum of Mathematics, Sigma, 2020 This paper solves the rational noncommutative analogue of Hilbert’s 17th problem: if a noncommutative rational function is positive semidefinite on all tuples of Hermitian matrices in its domain, then it is a sum of Hermitian squares of noncommutative ...
Jurij Volčič
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A New Algorithm for Positive Semidefinite Matrix Completion
Journal of Applied Mathematics, 2016 Positive semidefinite matrix completion (PSDMC) aims to recover positive semidefinite and low-rank matrices from a subset of entries of a matrix. It is widely applicable in many fields, such as statistic analysis and system control.
Fangfang Xu, Peng Pan
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