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241.
242.
The Ramanujan Journal - Let $${mathcal {A}}$$ , $${mathcal {B}}$$ be large subsets of $${1,ldots ,N}$$ . We study the distribution of the sum of binary digits of the sums $$a+b$$ with... 相似文献
243.
Henni Khadidja Louis Pierre-Yves Vannier Brigitte Moussa Ahmed 《Advances in Data Analysis and Classification》2020,14(3):543-570
Advances in Data Analysis and Classification - Clustering via marked point processes and influence space, Is-ClusterMPP, is a new unsupervised clustering algorithm through adaptive MCMC sampling of... 相似文献
244.
In this paper a comparison is made between two decomposition techniques to solve a staff scheduling problem with column generation.
In the first approach, decomposition takes place on the staff members, whereas in the second approach decomposition takes
place on the activities that have to be performed by the staff members. The resulting master LP is respectively a set partitioning
problem and a capacitated multi-commodity flow problem. Both approaches have been implemented in a branch-and-price algorithm.
We show a trade-off between modeling power and computation times of both techniques. 相似文献
245.
246.
The purpose of this article is to support the idea that “whenever we can prove a limit theorem in the classical sense for a dynamical system, we can prove a suitable almost-sure version based on an empirical measure with log-average”. We follow three different approaches: martingale methods, spectral methods and induction arguments. Our results apply, among others, to Axiom A maps or flows, to systems inducing a Gibbs–Markov map, and to the stadium billiard. 相似文献
247.
Alain-Yves LeRoux Marie-Noëlle LeRoux Jean-André Marti 《Comptes Rendus Mathematique》2004,339(4):313-316
The source waves are some particular solutions to genuinely non linear hyperbolic systems with a source term, whose propagation velocity is a constant determined by the roots of this source term. We propose a system of 2 equations on a 2 dimension space, which model the velocity field of the atmosphere near the ground. The source term is made of three parts: a given pressure gradient, a friction or aspiration effect and the Coriolis force. In the case where these parameters are constant, we build a solution which is a constant outside a circular crown. The internal circle represents the eye's wall of the hurricane and corresponds to a share shock wave. The external circle is a set generating the bifurcation which actually models the hurricane. To cite this article: A.-Y. LeRoux et al., C. R. Acad. Sci. Paris, Ser. I 339 (2004). 相似文献
248.
In this work, the effect of flexibility on the trajectory of a planar two-link manipulator is studied using integrated computer-aided design/analysis (CAD/CAE) procedures. The solid models and finite element models of the parts of the manipulator are created by using the CAD/CAE software I-DEAS. The assembly is defined, and knowing the payload and the end point trajectory, the velocities and accelerations of the parts, joint forces and driving torques are calculated using the rigid body dynamics. All the time dependent nodal forces acting on the parts including distributed gravity and inertia forces are created in files with the I-DEAS program file format. The finite element vibration analysis of the parts is performed by I-DEAS. The end point vibrations and the deviations from the rigid-body trajectory are analyzed for different types of end point acceleration curves. A circular trajectory is considered as an example. It is observed that the precision of the manipulator can be increased by testing different end point acceleration curves without changing the trajectory and the duration of the end point work. The procedure explained in this work can be used for this purpose successfully. 相似文献
249.
Various approaches and standards for transferring mathematical objects between different computer programs in multimedia environment in the framework of the OpenMath project are described. The use of these standards might revolutionize the exchange of mathematical information caused by the development of computer algebra tools and telecommunication possibilities. The standards make it possible to create databases and easily save and use mathematical objects obtained in different applications, e.g., to exchange the data obtained in different computer algebra systems and place information on the Internet. Bibliography: 9 titles. 相似文献
250.
Frédéric Coquel Thierry Gallouët Jean-Marc Hérard Nicolas Seguin 《Comptes Rendus Mathematique》2002,334(10):927-932
Closure laws for interfacial pressure and interfacial velocity are proposed within the frame work of two-pressure two-phase flow models. These enable us to ensure positivity of void fractions, mass fractions and internal energies when investigating field by field waves in the Riemann problem. To cite this article: F. Coquel et al., C. R. Acad. Sci. Paris, Ser. I 334 (2002) 927–932. 相似文献