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691.
A Trust-Region Method for Nonlinear Bilevel Programming: Algorithm and Computational Experience 总被引:7,自引:0,他引:7
Beno?t?ColsonEmail author Patrice?Marcotte Gilles?Savard 《Computational Optimization and Applications》2005,30(3):211-227
We consider the approximation of nonlinear bilevel mathematical programs by solvable programs of the same type, i.e., bilevel programs involving linear approximations of the upper-level objective and all constraint-defining functions, as well as a quadratic approximation of the lower-level objective. We describe the main features of the algorithm and the resulting software. Numerical experiments tend to confirm the promising behavior of the method. 相似文献
692.
693.
The structure of a sulfonated polyimide (sPI) ionomer membranes was investigated via the transport properties of various confined cations (7Li+, 23Na+, 87Rb+, 133Cs+). Their NMR spectra show large residual quadrupolar splitting depending on the orientation of the film in the static magnetic field B0. This behavior is the fingerprint of a macroscopic nematic ordering of charged interfaces. This is also confirmed by the anisotropy of the self-diffusion tensor measured by 1H and 7Li PGSE experiments on N(CH3)4+ and Li+ cations, respectively. 相似文献
694.
Hortalá MA Fabbrizzi L Marcotte N Stomeo F Taglietti A 《Journal of the American Chemical Society》2003,125(1):20-21
The imidazole group of histidine deprotonates and bridges the two CuII centers of a dimetallic polyamine macrocyclic complex, displacing the previously bound and quenched fluorescent indicator I. Thus, histidine recognition is signaled by the revival of the fluorescence of I. Selectivity with respect to other natural amino acids is achieved by choosing an indicator of tuned affinity toward the dicopper(II) receptor. 相似文献
695.
Laure?Verret Romain?Goutagny Patrice?Fort Laurène?Cagnon Denise?Salvert Lucienne?Léger Romuald?Boissard Paul?Salin Christelle?Peyron Pierre-Hervé?LuppiEmail author 《BMC neuroscience》2003,4(1):19
Background
Peptidergic neurons containing the melanin-concentrating hormone (MCH) and the hypocretins (or orexins) are intermingled in the zona incerta, perifornical nucleus and lateral hypothalamic area. Both types of neurons have been implicated in the integrated regulation of energy homeostasis and body weight. Hypocretin neurons have also been involved in sleep-wake regulation and narcolepsy. We therefore sought to determine whether hypocretin and MCH neurons express Fos in association with enhanced paradoxical sleep (PS or REM sleep) during the rebound following PS deprivation. Next, we compared the effect of MCH and NaCl intracerebroventricular (ICV) administrations on sleep stage quantities to further determine whether MCH neurons play an active role in PS regulation.Results
Here we show that the MCH but not the hypocretin neurons are strongly active during PS, evidenced through combined hypocretin, MCH, and Fos immunostainings in three groups of rats (PS Control, PS Deprived and PS Recovery rats). Further, we show that ICV administration of MCH induces a dose-dependant increase in PS (up to 200%) and slow wave sleep (up to 70%) quantities.Conclusion
These results indicate that MCH is a powerful hypnogenic factor. MCH neurons might play a key role in the state of PS via their widespread projections in the central nervous system.696.
R Séguin J-Y Potvin M Gendreau T G Crainic P Marcotte 《The Journal of the Operational Research Society》1997,48(2):162-174
This paper is concerned with a class of dynamic and stochastic problems known as real-time decision problems. The objective is to provide responses of a required quality in a continuously evolving environment, within a prescribed time frame, using limited resources and information that is often incomplete or uncertain. Furthermore, the outcome of any particular decision may also be uncertain. This paper provides an overview of this class of problems, reviews the relevant Artificial Intelligence literature, proposes a dynamic programming framework, and assesses the potential usefulness of Operational Research approaches for their solution. Throughout the paper, a vehicle dispatching application illustrates the relevant concepts. 相似文献
697.
In this paper we define (b*)-regularity for incident strataof a stratified set, a notion which refines Whitney (b)-regularity.We give three proofs that every subanalytic set admits a (b*)-regularstratification and we discuss some related properties. 相似文献
698.
Genevive Estenne Grrard Leclerc Pierre Dodey Patrice Renaut 《Journal of heterocyclic chemistry》1994,31(5):1121-1123
The protection of 2-substituted imidazole-5-methanol derivatives by tert-BDMS allowed the chlorination of the heterocycle in position 4 with good yield whereas direct chlorination on the imidazole alcohol was unsuccessful. 相似文献
699.
Polynomial-time algorithms are presented for solving combinatorial packing and covering problems defined from the integral feasible flows in an integral supply-demand network. These algorithms are also shown to apply to packing and covering problems defined by the minimal integral solutions to general totally unimodular systems. Analogous problems arising from matroid bases are also discussed and it is demonstrated that a means for solving such problems is provided by recent work of Cunningham. 相似文献
700.
Recent progress in reducing malaria cases and ensuing deaths is threatened by factors like mutations that induce resistance to artemisinin derivatives. Multiple drugs are currently in clinical trials for malaria treatment, including some with novel mechanisms of action. One of these, MMV390048, is a plasmodial kinase inhibitor. This review lists the recently developed molecules which target plasmodial kinases. A systematic review of the literature was performed using CAPLUS and MEDLINE databases from 2005 to 2020. It covers a total of 60 articles and describes about one hundred compounds targeting 22 plasmodial kinases. This work highlights the strong potential of compounds targeting plasmodial kinases for future drug therapies. However, the majority of the Plasmodium kinome remains to be explored. 相似文献