14,012 research outputs found
John von Neumann and the National Accounting Machine
A visit to D. H. Sadler, Superintendent, H.M. Nautical Almanac Office in 1943 by von Neumann and the author led to one of von Neumann's early contacts with programming
Paschke Dilations
In 1973 Paschke defined a factorization for completely positive maps between
C*-algebras. In this paper we show that for normal maps between von Neumann
algebras, this factorization has a universal property, and coincides with
Stinespring's dilation for normal maps into B(H).Comment: In Proceedings QPL 2016, arXiv:1701.0024
Cross-Points in Domain Decomposition Methods with a Finite Element Discretization
Non-overlapping domain decomposition methods necessarily have to exchange
Dirichlet and Neumann traces at interfaces in order to be able to converge to
the underlying mono-domain solution. Well known such non-overlapping methods
are the Dirichlet-Neumann method, the FETI and Neumann-Neumann methods, and
optimized Schwarz methods. For all these methods, cross-points in the domain
decomposition configuration where more than two subdomains meet do not pose any
problem at the continuous level, but care must be taken when the methods are
discretized. We show in this paper two possible approaches for the consistent
discretization of Neumann conditions at cross-points in a Finite Element
setting
Temperature control by laminar flows
We have demonstrated that given the inlet temperature, the procedure of using the heat transfer coefficient or the cooling region lengths to control the surface temperature is well-posed and the iterative procedure converges rapidly. An analysis on a slightly simpler problem using a Neumann condition with a primary cooling region also showed that the problem is indeed well-posed
Localization of compactness of Hankel operators on pseudoconvex domains
We prove the following localization for compactness of Hankel operators on
Bergman spaces. Assume that D is a bounded pseudoconvex domain in C^n, p is a
boundary point of D and B(p,r) is a ball centered at p with radius r so that
U=D\cap B(p,r) is connected. We show that if the Hankel operator H^D_f is
compact on A^2(D) (the symbols f is C^1 on the closure of D) then H^U_f is
compact on A^2(U) where A^2(D) and A^2(U) denote the Bergman spaces on D and U,
respectively.Comment: 9 pages. To appear in Illinois J. Mat
Buchbesprechungen
Besprochen werden die beiden folgenden Werke:
(1) Handbuch der Bodenkunde - Grundwerk. Von H. P. Blume , P. Felix-Henningsen, W.R. Fischer, H.-G. Frede, R. Horn u. K. Stahr.
(2) Thienemann, Johannes: Rossitten - drei Jahrzehnte auf der Kurischen Nehrung. Reprint der Ausgabe Melsungen, Neumann-Neudamm von 1930 (3.Aufl.)
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