Zobrazeno 1 - 10
of 92
pro vyhledávání: '"K.-H. Förster"'
Autor:
Paul Kallus, K.-H. Förster
Publikováno v:
Positivity. 21:711-738
We present multiplicative factorizations of positive elements in decomposing ordered Banach algebras. In order to apply strong factorization results to the Wiener algebra, we introduce the concept of semi-strongly decomposing algebras. Several applic
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5601c2f93dc57835536c08ae98dede0a
https://doi.org/10.1007/s11117-016-0452-y
https://doi.org/10.1007/s11117-016-0452-y
Autor:
P. Kallus, K.-H. Förster
Publikováno v:
Linear Algebra and its Applications. 498:471-489
We present an extension of the Perron–Frobenius theory to the numerical ranges of semi-monic Perron–Frobenius polynomials, namely matrix polynomials of the form Q ( λ ) = λ m I − ( λ l A l + ⋯ + A 0 ) = λ m I − A ( λ ) , where the coef
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b380b881143bdf1783a19e40d87f7365
https://doi.org/10.1016/j.laa.2015.12.019
https://doi.org/10.1016/j.laa.2015.12.019
Autor:
Béla Nagy, K.-H. Förster
Publikováno v:
Acta Scientiarum Mathematicarum. 80:233-260
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::95b6a9c9a6252307a60ee7373593adf1
https://doi.org/10.14232/actasm-012-012-z
https://doi.org/10.14232/actasm-012-012-z
Autor:
M. M. Nafalska, K.-H. Förster
Publikováno v:
Acta Mathematica Hungarica. 129:112-141
For a nonnegative operator KC in a Hilbert space H we give a description of all extremal extensions by means of the factors K and C. In particular, we discuss the Friedrichs and the Kreĭn-von Neumann extension of KC. Applications to systems of diffe
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5b25fe04503a783158ec564f0b810d96
https://doi.org/10.1007/s10474-010-9248-x
https://doi.org/10.1007/s10474-010-9248-x
Autor:
K.-H. Förster, Vladimír Müller
Publikováno v:
Studia Mathematica. 174:61-73
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::95715b271e88d5f2b84158d64395d6b7
https://doi.org/10.4064/sm174-1-5
https://doi.org/10.4064/sm174-1-5
Autor:
K.-H. Förster, Béla Nagy
Publikováno v:
SIAM Journal on Matrix Analysis and Applications. 25:1032-1045
It is one of the basic facts of linear time-invariant systems theory that any two minimal (canonical) realizations are connected in the best possible way: by system similarity. We study five different types of possible connections between two arbitra
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5f2e40e04254a0092d67f149d3191b75
https://doi.org/10.1137/s0895479802410013
https://doi.org/10.1137/s0895479802410013
Autor:
K.-H. Förster, Béla Nagy
Publikováno v:
Proceedings of the American Mathematical Society. 132:1181-1193
Unitary operators in Hilbert space map an orthonormal basis onto another. In this paper we study those that map an orthonormal basis onto itself. We show that a sequence of cardinal numbers is a complete set of unitary invariants for such an operator
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::aeac76a537361b761b954a2d888faa36
https://doi.org/10.1090/s0002-9939-03-07202-2
https://doi.org/10.1090/s0002-9939-03-07202-2
Autor:
Béla Nagy, K.-H. Förster
Publikováno v:
Linear Algebra and its Applications. 311(1-3):107-129
Various aspects of the nonnegative, finite-dimensional realizability of time-invariant discrete linear systems are considered. A new proof of the basic result of the nonnegative realizability of a primitive (scalar-valued) transfer function with nonn
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::14f235c83e8c0a489e0c71421ae89fc7
Autor:
Béla Nagy, K.-H. Förster
Publikováno v:
Proceedings of the American Mathematical Society. 128:1167-1176
For any triangular operator matrix acting in a direct sum of complex Banach spaces, the order of a pole of the resolvent (i.e. the index) is determined as a function of the coefficients in the Laurent series for all the (resolvents of the) operators
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::705a24ffec0d4dab4507b43f61d77a48
https://doi.org/10.1090/s0002-9939-99-05341-1
https://doi.org/10.1090/s0002-9939-99-05341-1
Autor:
K.-H. Förster, B. Nagy
Publikováno v:
Publicationes Mathematicae Debrecen. 52:367-376
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::0725268f747b215a04d98000f9ffb912
https://doi.org/10.5486/pmd.1998.2033
https://doi.org/10.5486/pmd.1998.2033