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11.
12.
Carsten Franz 《Proceedings of the American Mathematical Society》2006,134(8):2437-2446
A method to approximate the eigenvalues of linear operators depending on an unknown distribution is introduced and applied to weighted sums of squared normally distributed random variables. This area of application includes the approximation of the asymptotic null distribution of certain degenerated U- and V-statistics.
13.
14.
We describe links between a recently introduced semidefinite relaxation for the max-cut problem and the well known semidefinite
relaxation for the stable set problem underlying the Lovász’s theta function. It turns out that the connection between the
convex bodies defining the semidefinite relaxations mimics the connection existing between the corresponding polyhedra. We
also show how the semidefinite relaxations can be combined with the classical linear relaxations in order to obtain tighter
relaxations.
This work was done while the author visited CWI, Amsterdam, The Netherlands.
Svata Poljak untimely deceased in April 1995. We shall both miss Svata very much. Svata was an excellent colleague, from whom
we learned a lot of mathematics and with whom working was always a very enjoyable experience; above all, Svata was a very
nice person and a close friend of us.
The research was partly done while the author visited CWI, Amsterdam, in October 1994 with a grant fom the Stieltjes Institute,
whose support is gratefully acknowledged. Partially supported also by GACR 0519.
Research support by Christian Doppler Laboratorium für Diskrete Optimierung. 相似文献
15.
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17.
Franz Merkl 《Probability Theory and Related Fields》2003,126(3):307-338
This article describes the almost sure infinite volume asymptotics of the ground state energy of random Schr?dinger operators
with scaled Gibbsian potentials. The random potential is obtained by distributing soft obstacles according to an infinite
volume grand canonical tempered Gibbs measure with a superstable pair interaction. There is no restriction on the strength
of the pair interaction: it may be taken, e.g., at a critical point. The potential is scaled with the box size in a critical
way, i.e. the scale is determined by the typical size of large deviations in the Gibbsian cloud. The almost sure infinite
volume asymptotics of the ground state energy is described in terms of two equivalent deterministic variational principles
involving only thermodynamic quantities. The qualitative behaviour of the ground state energy asymptotics is analysed: Depending
on the dimension and on the H?lder exponents of the free energy density, it is identified which cases lead to a phase transition
of the asymptotic behaviour of the ground state energy.
Received: 24 June 2002 / Revised version: 17 February 2003
Published online: 12 May 2003
Mathematics Subject Classification (2000): Primary 82B44; Secondary 60K35
Key words or phrases: Gibbs measure – H?lder exponents – Random Schr?dinger operator – Ground state – Large deviations 相似文献
18.
Monika Schuster Robert Inführ Claudia Turecek Jürgen Stampfl Franz Varga Robert Liska 《Monatshefte für Chemie / Chemical Monthly》2006,4(4):843-853
To substitute cross-linked photopolymers in rapid prototyping of mold materials and therefore extend the range of materials
which can be casted, organo-soluble photopolymers were developed. Branched bisalkylacrylamides were suitable as base component
for such formulations, due to their high reactivity, good mechanical properties, and excellent solubility of the formed polymers.
These molding materials were used to prepare cellular biocompatible materials which could be used as bone replacement materials.
Biocompatible crosslinkers based on methacrylates from hydrolyzed gelatine or lactic acid ethyleneglycol blockcopolymers and
commercially available reactive diluents are the base components of such a formulation. Biocompatibility was investigated
by osteoblast-like cells. Cellular biocompatible parts were obtained by thermal polymerization in soluble mould materials
prepared by 3D-photoshaping. 相似文献
19.
In this paper the distribution of the zeros of the error function for bestL
1-approximation by rational functions fromR
n,m
is considered. It is shown that the maximal distance between such zeros isO(1/(n–m)), ifn > m.Communicated by Edward B. Saff. 相似文献
20.
Franz Salzer 《Fresenius' Journal of Analytical Chemistry》1955,146(4):260-273
Zusammenfassung Es werden Methoden beschrieben, mit deren Hilfe Glyoxal und Glyoxylsäure nebeneinander bestimmt werden können. Die Summe der Carbonylverbindungen wird mit einer bekannten Menge Semicarbazid zu den Semicarbazonen umgesetzt und das überschüssige Semicarbazid jodometrisch bestimmt. Glyoxal allein wird in einer zweiten Bestimmung mit Lauge nach Cannizzaro in glykolsaures Natrium umgesetzt und der dafür erforderliche Laugeverbrauch titrimetrisch bestimmt. Aus der Summe Glyoxal + Glyoxylsäure einerseits und der Glyoxalbestimmung andererseits läßt sich der Glyoxylsäuregehalt berechnen. 相似文献