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91.
We introduce here some Itô calculus for non-continuous Dirichlet processes. Such calculus extends what was known for continuous Dirichlet processes or for semimartingales. In particular we prove that non-continuous Dirichlet processes are stable under C
1 transformation. 相似文献
92.
Régine Barthelmé 《Comptes Rendus Mathematique》2005,341(11):689-694
This Note introduces a new integral form of the charge and current deposition scheme given in 1992 by Villasenor and Buneman, which permits the conservation of charge in PIC codes. This integral form extends directly to higher order spline shape factors, whose use produces less numerical noise. We thus get a discrete charge conserving method for high order shape factors. This method extends easily to nonuniform Cartesian grids for first order shape factors. To cite this article: R. Barthelmé, C. R. Acad. Sci. Paris, Ser. I 341 (2005). 相似文献
93.
Tereza C. R. dos Santos Ricardo Q. Aucélio Reinaldo C. Campos 《Mikrochimica acta》2003,142(1-2):63-66
A simple and direct spectrofluorimetric method has been developed for the determination of aluminum using alizarin red PS
(1,2,4-trihydroxy 9,10-anthraquinone-3-sulfonic acid). The method is based on the strong fluorescence (480/564 nm) of Al3+ and alizarin red. Experimental parameters such as pH, concentration of the ligand, ionic strength of the solution, reaction
time and temperature were optimized in order to maximize the analytical signal. Interferences of several ions (anions and
cations) were studied and evaluated. The linear range of the method extends from 3 to 100 μg L−1. Limit of detection (3sb) was 0.9 μg L−1. The method was tested with a silicate certified reference material. Interferences were eliminated by a liquid extraction
with cupferron.
Author for correspondence. E-mail: aucelior@rdc.puc-rio.br
Received September 10, 2002; accepted January 15, 2003
Published online May 5, 2003 相似文献
94.
J.-F. Pascual-Sánchez A. San Miguel F. Vicente 《General Relativity and Gravitation》2004,36(9):2075-2083
We analyze the geometry of a rotating disk with a tangential acceleration in the framework of the theory of Special Relativity, using the kinematic linear differential system that verifies the relative position vector of time-like curves in a Fermi reference. A numerical integration of these equations for a generic initial value problem is made up and the results are compared with those obtained in other works. 相似文献
95.
C Guéret N Jussien O Lhomme C Pavageau C Prins 《The Journal of the Operational Research Society》2003,54(5):458-465
In this paper, we describe an aircraft loading problem submitted by the French military agency (DGA) as part of a more general military airlift planning problem. It can be viewed as a kind of bi-dimensional bin-packing problem, with heterogeneous bins and several additional constraints. We introduce two-phase methods for solving this NP-hard problem. The first phase consists in building good initial solutions, thanks to two fast algorithms: a list-based heuristic and a loading pattern generation method. Both algorithms call a constraint-based subroutine, able to determine quickly if the items already loaded can be reshuffled to accommodate a new object. The second phase improves these preliminary solutions using local search techniques. Results obtained on real data sets are presented. 相似文献
96.
Grégory Duby 《Archive for Mathematical Logic》2003,42(5):435-447
This paper generalizes results of F. K?rner from [4] where she established the existence of maximal automorphisms (i.e. automorphisms
moving all non-algebraic elements). An ω-maximal automorphism is an automorphism whose powers are maximal automorphisms. We
prove that any structure has an elementary extension with an ω-maximal automorphism. We also show the existence of ω-maximal
automorphisms in all countable arithmetically saturated structures. Further we describe the pairs of tuples (ˉa,ˉb) for which there is an ω-maximal automorphism mapping ˉa to ˉb.
Received: 12 December 2001 /
Published online: 10 October 2002
Supported by the ``Fonds pour la Formation à la Recherche dans l'Industrie et dans l'Agriculture'
Mathematics Subject Classification (2000): Primary: 03C50; Secondary: 03C57
Key words or phrases: Automorphism – Recursively saturated structure 相似文献
97.
O. Perru F. Ibrahim O. Bajeat C. Bourgeois F. Clapier E. Cottereau C. Donzaud M. Ducourtieux S. Galès D. Guillemaud-Mueller C. Lau H. Lefort F. Le Blanc A. C. Mueller J. Obert N. Pauwels J. C. Potier F. Pougheon J. Proust B. Roussière J. Sauvage O. Sorlin D. Verney 《Physics of Atomic Nuclei》2003,66(8):1421-1427
The PARRNe facility has been used to produce neutron-rich isotopes 83,84Gaby the ISOL method. Their decay has been studied, and β-γ coincidence and γ-γ coincidence data were collected as a function of time. The first two excited levels in 83Ge and the first excited level in 84Ge have been measured for the first time. 相似文献
98.
Various physical systems of dispersive waves admit solutions in the form of generalized solitary waves. Such waves result from the resonance between a long localized wave and short periodic oscillations. Many estimates (rigorous and numerical) have been given for the amplitude of the ripples in the tail of the generalized solitary wave when its central part has a sech2 shape. This Note provides estimates (not yet rigorous) for the ripple amplitude when the central part is flat and wide. To cite this article: C. Fochesato, F. Dias, C. R. Acad. Sci. Paris, Ser. I 337 (2003). 相似文献
99.
Antonio Guirado Enrique LópezSánchez Raquel Andreu Andrés Zapata 《Tetrahedron letters》2004,45(10):2075-2076
The first method for the synthesis of the title compounds has been established involving a stereoselective electrochemical diacylation process. The cathodic reductions of monothiobenzils in an aprotic medium, under constant potential, in the presence of twofold molecular amounts of aroyl chlorides provide previously unknown (Z)-α-benzoyloxy-β-benzoythiostilbenes in high to quantitative yields. 相似文献
100.
Recent mass measurements of proton-rich nuclei close to the N=Z line were used for the calculation of the interaction strength δV pn between valence protons and neutrons. When compared with δV pn values calculated from mass values of the AME’95 mass tables, the breaking down of the SU(4) symmetry is verified at Z=32,33,34. 相似文献