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31.
32.
Marc Bonnet 《International Journal of Solids and Structures》2008,45(2):705-707
The aim of this discussion is to expose incorrect results in a previous IJSS article. 相似文献
33.
Jean-Pierre Françoise 《Journal of Dynamics and Differential Equations》2008,20(4):777-786
This article is devoted to one-dimensional perturbative theory on R × S
1. There is a recursive formula for the successive obstructions to parametric center at any order of the perturbation parameter.
The first obstruction is studied by means of complex analysis techniques. This extends to the trigonometric case what was
done previously for the polynomial case (Israel J. Math. 142, 273–283, 2004).
This article is dedicated to Professor Zhang Zhi-Fen on the occasion of her 80th Birthday 相似文献
34.
35.
When trains of impulse controls are present on the right-hand side of a system of ordinary differential equations, the solution
is no longer smooth and contains jumps which can accumulate at several points in the time interval. In technological and physical
systems the sum of the absolute value of all the impulses is finite and hence the total variation of the solution is finite.
So the solution at best belongs to the space BV of vector functions with bounded variation. Unless variable node methods are
used, the loss of smoothness of the solution would a priori make higher-order methods over a fixed mesh inactractive. Indeed
in general the order of -convergence is and the nodal rate is . However in the linear case -convergence rate remains but the nodal rate can go up to by using one-step or multistep scheme with a nodal rate up to when the solution belongs to . Proofs are given of error estimates and several numerical experiments confirm the optimality of the estimates.
Received March 15, 1996 / Revised version received January 3, 1997 相似文献
36.
37.
Marc Visseaux Mickael Terrier Andr Mortreux Pascal Roussel 《Comptes Rendus Chimie》2007,10(12):1195-1199
The reaction of one equivalent of Nd(BH4)3(THF)3 with an half equivalent of dialkylmagnesium in the presence of a stoichiometric amount of pentamethylcyclopentadiene cleanly affords a new kind of half-sandwich of neodymium that is stable toward comproportionation. This strategy can be advantageously applied to generate in situ catalysts allowing the controlled polymerisation of isoprene. 相似文献
38.
We examine the resource allocation problem of partitioning identical servers into two parallel pooling centers, and simultaneously
assigning job types to pooling centers. Each job type has a distinct Poisson arrival rate and a distinct holding cost per
unit time. Each pooling center becomes a queueing system with an exponential service time distribution. The goal is to minimize
the total holding cost. The problem is shown to be polynomial if a job type can be divided between the pooling centers, and
NP-hard if dividing job types is not possible. When there are two servers and jobs cannot be divided, we demonstrate that
the two pooling center configuration is rarely optimal. A heuristic which checks the single pooling center has an upper bound
on the relative error of 4/3. The heuristic is extended for the multiple server problem, where relative error is bounded above
by the number of servers.
相似文献
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40.