Zobrazeno 1 - 10
of 154
pro vyhledávání: '"Hwa Long Gau"'
Autor:
PEI YUAN WU1 pywu@math.nctu.edu.tw, HWA-LONG GAU2 hlgau@math.ncu.edu.tw
Publikováno v:
Acta Scientiarum Mathematicarum. Aug2022, Vol. 88 Issue 1/2, p527-545. 19p.
Autor:
Hwa-Long Gau, Pei Yuan Wu
Publikováno v:
Linear Algebra and its Applications. 650:60-74
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::6aa81cb0cd0e51fca23b59de066643d0
https://doi.org/10.1016/j.laa.2022.05.017
https://doi.org/10.1016/j.laa.2022.05.017
Publikováno v:
Studia Mathematica. 263:267-291
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a51f64e7a464cca6e821f0b6a10dc9ca
https://doi.org/10.4064/sm201020-30-7
https://doi.org/10.4064/sm201020-30-7
Publikováno v:
Linear Algebra and its Applications. 610:766-784
We study properties of the numerical ranges of Foguel operators F T = [ S ⁎ 0 T S ] , where S is the simple unilateral shift and T is some operator, both acting on l 2 . Among other things, we show that (1) if T is nonzero compact, then the numeric
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::4a60eff0dc459b6eccacd90541d5c580
https://doi.org/10.1016/j.laa.2020.10.017
https://doi.org/10.1016/j.laa.2020.10.017
Autor:
Kuo-Zhong Wang, Hwa Long Gau
Publikováno v:
Linear Algebra and its Applications. 603:190-211
Let K 2 = [ 0 2 0 0 ] , K n be the n × n weighted shift matrix with weights 2 , 1 , … , 1 ︸ n − 3 , 2 for all n ≥ 3 , and K ∞ be the weighted shift operator with weights 2 , 1 , 1 , 1 , … . In this paper, we show that if an n × n nonzer
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::bcb740a66b7fc7c3fd871a75fa18c749
https://doi.org/10.1016/j.laa.2020.05.039
https://doi.org/10.1016/j.laa.2020.05.039
Publikováno v:
Linear Algebra and its Applications. 578:95-110
For an n-by-n matrix A, we determine when the numerical ranges W ( A k ) , k ≥ 1 , of powers of A are all equal to each other. More precisely, we show that this is the case if and only if A is unitarily similar to a direct sum B ⊕ C , where B is
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::687a4a455a208bcdf61d6d0b365fdaaa
https://doi.org/10.1016/j.laa.2019.05.013
https://doi.org/10.1016/j.laa.2019.05.013
Autor:
Yueh Hua Lu, Hwa Long Gau
Publikováno v:
Linear Algebra and its Applications. 565:82-98
For n-by-n and m-by-m complex matrices A and B, respectively, it is known that the inequality w ( A ⊗ B ) ≤ ‖ A ‖ w ( B ) holds, where w ( ⋅ ) and ‖ ⋅ ‖ denote, respectively, the numerical radius and the operator norm of a matrix. In
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::4adc61bfa4afdf1c3ae2844cebb61306
https://doi.org/10.1016/j.laa.2018.12.008
https://doi.org/10.1016/j.laa.2018.12.008