Results 141 to 150 of about 71,699 (272)

Some inequalities for unitarily invariant norms of matrices

Journal of Inequalities and Applications, 2011
This article aims to discuss inequalities involving unitarily invariant norms. We obtain a refinement of the inequality shown by Zhan. Meanwhile, we give an improvement of the inequality presented by Bhatia and Kittaneh for the Hilbert-Schmidt norm ...
Wang Shaoheng, Zou Limin, Jiang Youyi
doaj  

Enhanced Young-type inequalities utilizing Kantorovich approach for semidefinite matrices

Open Mathematics
This article introduces new Young-type inequalities, leveraging the Kantorovich constant, by refining the original inequality. In addition, we present a range of norm-based inequalities applicable to positive semidefinite matrices, such as the Hilbert ...
Bani-Ahmad Feras, Rashid Mohammad Hussein Mohammad   +1 more
doaj   +1 more source

A Generalized HSS Iteration Method for Continuous Sylvester Equations

Journal of Applied Mathematics, 2014
Based on the Hermitian and skew-Hermitian splitting (HSS) iteration technique, we establish a generalized HSS (GHSS) iteration method for solving large sparse continuous Sylvester equations with non-Hermitian and positive definite/semidefinite matrices ...
Xu Li, Yu-Jiang Wu, Ai-Li Yang, Jin-Yun Yuan   +3 more
doaj   +1 more source

On vector configurations that can be realized in the cone of positive matrices

, 2010
Let $v_1$,..., $v_n$ be $n$ vectors in an inner product space. Can we find a natural number $d$ and positive (semidefinite) complex matrices $A_1$,..., $A_n$ of size $d \times d$ such that ${\rm Tr}(A_kA_l)= $ for all $k,l=1,..., n$? For such matrices to
Frenkel, Péter E., Weiner, Mihály
core  

More inequalities for positive semidefinite matrices

The Electronic Journal of Linear Algebra
In this paper, we first present a necessary and sufficient condition for a class of block matrices to be positive semidefinite. Second, we demonstrate the significance of a known inequality (as presented in [5]) through a norm inequality. Finally, utilizing the polar decomposition, we provide a functional version of a singular value inequality.
Feng Zhang, Hefang Jing
openaire   +1 more source

On the Disentanglement of an Economic Union

Journal of Regional Science, Volume 66, Issue 1, Page 244-269, January 2026.
ABSTRACT We study how the unilateral withdrawal of a region from an economic union affects the spatial distribution of economic activity and social welfare. We explore a three‐region economic geography model under the assumption that this withdrawal can be expressed as a higher transportation cost between the leaving party and the remaining union ...
Jorge Saraiva, José M. Gaspar, Kiyohiro Ikeda   +2 more
wiley   +1 more source

Robust Λ$\Lambda$‐Quantiles and Extremal Distributions

Mathematical Finance, Volume 36, Issue 1, Page 3-19, January 2026.
ABSTRACT In this paper, we investigate the robust models for Λ$\Lambda$‐quantiles with partial information regarding the loss distribution, where Λ$\Lambda$‐quantiles extend the classical quantiles by replacing the fixed probability level with a probability/loss function Λ$\Lambda$.
Xia Han, Peng Liu
wiley   +1 more source

Singular value inequalities for matrices related to convex and concave functions

Journal of Inequalities and Applications
In this note, we give several singular value inequalities involving convex and concave functions, which can be considered as generalizations of Al-Natoor et al.’s results (J. Math. Inequal. 17:581–589, 2023).
Shengyan Ma, Lihong Hu, Xiaohui Fu
doaj   +1 more source

On semidefinite representations of plane quartics

, 2008
This note focuses on the problem of representing convex sets as projections of the cone of positive semidefinite matrices, in the particular case of sets generated by bivariate polynomials of degree four.
Henrion, Didier
core   +5 more sources

A Three‐Dimensional Filter‐Based SSDP Method for Nonlinear Semidefinite Programming With Its Applications

Journal of Mathematics, Volume 2026, Issue 1, 2026.
Recently, there has been significant interest in filter methods for solving nonlinear problems. Extensions of these methods to nonlinear semidefinite programming (NLSDP) problems are described. A three‐dimensional filter sequential semidefinite programming (SSDP) algorithm with a feasible restoration phase is presented to efficiently solve NLSDPs with ...
Dandan Li, Songhua Wang, Pramita Mishra
wiley   +1 more source