Results 11 to 20 of about 651,067 (291)

Convexity of the joint numerical range: topological and differential geometric viewpoints

Linear Algebra and its Applications, 2004
The authors study the convexity of the joint numerical range of finite families of Hermitian matrices. A sufficient condition is expressed in terms of the behaviour of the largest eigenvalue of the linear combinations, over the real unit sphere of corresponding dimension, of the given matrices.
Gutkin, Eugene, Jonckheere, Edmond A., Karow, Michael   +2 more
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Joint separable numerical range and bipartite entanglement witness [PDF]

Journal of Physics A: Mathematical and Theoretical, 2020
In 2017 an idea considering a pair of Hermitian operators of product form was published, which is called ultrafine entanglement witnessing. In 2018 some rigorous results were given. Here we improve their work. First we point this idea can be directly derived from an earlier concept named joint separable numerical range and explain how it works as a ...
Wu, Pan, Tang, Runhua
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Joint numerical ranges and commutativity of matrices

Journal of Mathematical Analysis and Applications, 2020
The connection between the commutativity of a family of $n\times n$ matrices and the generalized joint numerical ranges is studied. For instance, it is shown that ${\cal F}$ is a family of mutually commuting normal matrices if and only if the joint numerical range $W_k(A_1, \dots, A_m)$ is a polyhedral set for some $k$ satisfying $|n/2-k|\le 1$, where $
Chi-Kwong Li, Yiu-Tung Poon, Ya-Shu Wang
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Numerical ranges of an operator on an indefinite inner product space [PDF]

, 1996
For n x n complex matrices A and an n x n Hermitian matrix S, we consider the S-numerical range of A and the positive S-numerical range of A defined by WS(A) = {〈Av, v〉S/〈v, v〉S : v ∈ ℂn, 〈v, v〉S ≠ 0} and W S + (A) = {〈Av, v〉S : v ∈ ℂn, 〈v, v〉S = 1 ...
Li, CK, Tsing, NK, Uhlig, F
core   +2 more sources

A Fast PARAFAC Algorithm for Parameter Estimation in Monostatic FDA-MIMO Radar

Remote Sensing, 2022
This paper studies the joint range and angle estimation of monostatic frequency diverse array multiple-input multiple-output (FDA-MIMO) radar and proposes a joint estimation algorithm. First, the transmit direction matrix is converted into real values by
Wenshuai Wang, Xiang Lan, Jinmei Shi, Xianpeng Wang   +3 more
doaj   +1 more source

Tensor Products and Joint Numerical Range [PDF]

Proceedings of the American Mathematical Society, 1973
It is shown that the joint numerical range of the tensor product of several operators is the cartesian product of their numerical ranges.
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Multiplicities, boundary points, and {joint} numerical ranges [PDF]

Operators and Matrices, 2011
The multiplicity of a point in the joint numerical range W (A1,A2,A3) ⊆ R3 is studied for n× n Hermitian matrices A1,A2,A3 . The relative interior points of W (A1,A2,A3) have multiplicity greater than or equal to n− 2 . The lower bound n− 2 is best possible. Extreme points and sharp points are studied. Similar study is given to the convex set V (A) := {
Wai-Shun Cheung, Xuhua Liu, Tin-Yau Tam
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Joint Radar-Communication System Design Based on FDA-MIMO via Frequency Index Modulation

IEEE Access, 2023
The index modulation based on multiple-antenna architecture is a prospective information embedding approach for the joint radar-communication system (JRCS).
Mengjiao Li, Wen-Qin Wang
doaj   +1 more source

On the joint numerical status and tensor products

International Journal of Mathematics and Mathematical Sciences, 1990
We prove a result on the joint numerical status of the bounded Hilbert space operators on the tensor products. The result seems to have nice applications in the multiparameter spectral theory.
Ram Verma, Lokenath Debnath
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Monocular camera-based 3D human body pose estimation by Generative Adversarial Network considering joint range of motion represented by quaternion

Journal of Biomechanical Science and Engineering, 2023
This study aims to establish a monocular camera-based system that uses a generative adversarial network (GAN) to estimate a 3D pose of a human and his/her orientation relative to the camera from images by considering anatomical knowledge such as segment ...
Akisue KURAMOTO, Kosuke MIZUKOSHI, Motomu NAKASHIMA   +2 more
doaj   +1 more source