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991.
Majstorović Snježana Sabo Kristian Jung Johannes Klarić Matija 《Central European Journal of Operations Research》2018,26(3):715-737
Central European Journal of Operations Research - The growth curve clustering problem is analyzed and its connection with the spectral relaxation method is described. For a given set of growth... 相似文献
992.
Given a family of Calabi-Yau varieties over the punctured disc or over the field of Laurent series, we show that, after a finite base change, the family can be extended across the origin while keeping the canonical class trivial. More generally, we prove similar extension results for families whose log-canonical class is semi-ample. We use these to show that the Berkovich and essential skeleta agree for smooth varieties over C((t)) with semi-ample canonical class. 相似文献
993.
We establish first parts of a tropical intersection theory. Namely, we define cycles, Cartier divisors and intersection products
between these two (without passing to rational equivalence) and discuss push-forward and pull-back. We do this first for fans in
\mathbbRn{\mathbb{R}^{n}} and then for “abstract” cycles that are fans locally. With regard to applications in enumerative geometry, we finally have
a look at rational equivalence and intersection products of cycles and cycle classes in
\mathbbRn{\mathbb{R}^{n}} . 相似文献
994.
To compare continued fraction digits with the denominators of the corresponding approximants we introduce the arithmetic-geometric
scaling. We will completely determine its multifractal spectrum by means of a number-theoretical free-energy function and
show that the Hausdorff dimension of sets consisting of irrationals with the same scaling exponent coincides with the Legendre
transform of this free-energy function. Furthermore, we identify the asymptotic of the local behaviour of the spectrum at
the right boundary point and discuss a connection to the set of irrationals with continued-fraction digits exceeding a given
number which tends to infinity. 相似文献
995.
The slab band quantum computational approach in the Vienna ab initio simulation package (VASP) is used to calculate the adsorption energies of reactants, reaction intermediates, and products in O2 reduction and in water oxidation in acid on three crystallographic surfaces of pentlandite structure Co9S8. Reversible potentials for the reaction steps involving electron and proton transfer are determined by using the energies in a linear Gibbs free energy relationship. On the basis of these results, we find that the partially OH-covered (202) surface is active toward O2 reduction and should have overpotential behavior similar to that observed for platinum electrodes. One structure in the predicted four-electron reduction mechanism is novel: S2- provides an adsorption site for O following O-O bond scission, which, unlike the case of platinum electrodes, takes place prior to the first reduction step. 相似文献
996.
Stationary spatiotemporal pattern formation emerging from the electric activity of biological membranes is widespread in cells and tissues. A known key instability comes from the self-aggregation of membrane channels. In a two-dimensional geometry, we show that the primary pattern undergoes four secondary instabilities: Eckhaus-like, period-halving, drift instabilities, and a global oscillation. The stability diagram is determined. The parity-breaking (drift) bifurcation of channel density is characterized analytically and numerically. 相似文献
997.
Alexandre Boulay Sophie Laine Nadine Leygue Eric Benoist Sophie Laurent Luce Vander Elst Robert N. Muller Béatrice Mestre-Voegtle Claude Picard 《Tetrahedron letters》2013
In the design of dual-imaging probes, the first functionalized and neutral heterobimetallic Re(I)–Gd(III) complex, highly soluble in aqueous solutions, has been prepared. This system exhibits interesting photophysical properties (λem = 578 nm, ? = 1.4%) for optical imaging and substantial higher relaxivity (r1 = 6.6 mM−1 s−1 at 0.47 T and 37 °C) than the clinically used MRI contrast agents. Moreover, this system incorporates an aromatic ester functionality suitable for bioconjugation. 相似文献
998.
The article gives constructions of disjoint 5‐designs obtained from permutation groups and extremal self‐dual codes. Several new simple 5‐designs are found with parameters that were left open in the table of 5‐designs given in (G. B. Khosrovshahi and R. Laue, t‐Designs with t⩾3, in “Handbook of Combinatorial Designs”, 2nd edn, C. J. Colbourn and J. H. Dinitz (Editors), Chapman & Hall/CRC, Boca Raton, FL, 2007, pp. 79–101), namely, 5−(v, k, λ) designs with (v, k, λ)=(18, 8, 2m) (m=6, 9), (19, 9, 7m) (m=6, 9), (24, 9, 6m) (m=3, 4, 5), (25, 9, 30), (25, 10, 24m) (m=4, 5), (26, 10, 126), (30, 12, 440), (32, 6, 3m) (m=2, 3, 4), (33, 7, 84), and (36, 12, 45n) for 2⩽n⩽17. These results imply that a simple 5−(v, k, λ) design with (v, k)=(24, 9), (25, 9), (26, 10), (32, 6), or (33, 7) exists for all admissible values of λ. © 2010 Wiley Periodicals, Inc. J Combin Designs 18: 305–317, 2010 相似文献
999.
We present an improved stochastic model concerning the lay-down of fibers on a conveyor belt in the production of nonwovens. The model is based on stochastic differential equations describing the resulting position of the fiber on the belt having regard to its motion in the deposition region under influence of turbulent air flow. Our aim is to generalize an existing model to 3D. By introducing a parameter we have an alternative to consider both isotropic and anisotropic orientation of the fibers generating the nonwoven. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
1000.
István Berkes Lajos Horváth Johannes Schauer 《Probability Theory and Related Fields》2010,147(3-4):449-479
Selection from finite sets is a basic procedure of statistics and the partial sum behavior of selected elements is completely known under the “uniform asymptotic negligibility” condition of central limit theory. The purpose of the present paper is to determine the asymptotic behavior of partial sums when the central limit theorem fails. As an application, we describe the limiting properties of permutation and bootstrap statistics in case of infinite variance. 相似文献