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601.
Mihai Anitescu 《Mathematical Programming》2002,92(2):359-386
We analyze the convergence of a sequential quadratic programming (SQP) method for nonlinear programming for the case in which
the Jacobian of the active constraints is rank deficient at the solution and/or strict complementarity does not hold for some
or any feasible Lagrange multipliers. We use a nondifferentiable exact penalty function, and we prove that the sequence generated
by an SQP using a line search is locally R-linearly convergent if the matrix of the quadratic program is positive definite
and constant over iterations, provided that the Mangasarian-Fromovitz constraint qualification and some second-order sufficiency
conditions hold.
Received: April 28, 1998 / Accepted: June 28, 2001?Published online April 12, 2002 相似文献
602.
603.
Mihai Tib?r 《Topology》2004,43(3):619-633
We prove an extended Lefschetz principle for a large class of pencils of hypersurfaces having isolated singularities, possibly in the axis, and show that the module of vanishing cycles is generated by the images of certain variation maps. 相似文献
604.
Mihai Ciucu 《Combinatorica》1996,16(3):321-324
A point set satisfies the Steinhaus property if no matter how it is placed on a plane, it covers exactly one integer lattice point. Whether or not such a set exists, is an open problem. Beck has proved [1] that any bounded set satisfying the Steinhaus property is not Lebesgue measurable. We show that any such set (bounded or not) must have empty interior. As a corollary, we deduce that closed sets do not have the Steinhaus property, fact noted by Sierpinski [3] under the additional assumption of boundedness. 相似文献
605.
I. M. Brâncuş I. Berceanu A. Buţă C. Grama I. Lazăr I. Mihai M. Petraşcu V. Simion A. Constantinescu 《Zeitschrift für Physik A Hadrons and Nuclei》1985,321(3):443-449
We examine the way in which local field effects in the neutron refractive index affect the values of coherent scattering lengths determined by various kinds of neutron optical measurements. We find that under typical experimental conditions these effects are negligible for interferometry measurements but that they are significant for gravity refractometry measurements, producing changes in the effective scattering length of as much as two or three standard deviations in some cases. Refined values of the scattering lengths are obtained for the thirteen elements for which data are presently available. The special role of local field effects in neutron transmission is also discussed. 相似文献
606.
607.
Mihai Şabac 《Journal of Functional Analysis》1983,52(3):303-314
Some results concerning the operatorially irreducible, topologically irreducible, operatorially and topologically irreducible representations of a class of infinite-dimensional Lie algebras by bounded operators in a complex Banach space are obtained. 相似文献
608.
Sorin Mager Mihai Horn Ion Grosu Mircea Bogdan 《Monatshefte für Chemie / Chemical Monthly》1989,120(8-9):735-742
Summary Mono- and trispiro-1,3-dioxanes with mobile, fixed and semimobile structures were obtained by the condensation reaction of pentaerythritol with aldehydes and symmetrical or unsymmetrical ketones. The conformational analysis of the obtained compounds was undertaken by means of1H-NMR spectroscopy. The spiro-1,3-dioxanes obtained with aldehydes or nonsymmetrical ketones represent fixed (anancomeric) structures. Ketalisation with 4-t-butyl-cyclohexanone leads to a semimobile structure of a trispiro-1,3-dioxane in which the two marginal cyclohexanic rings are fixed, while the two middle ones are mobile, continuously flipping at room temperature. The solvent effect on the NMR spectra is also discussed. Utilisation of benzene-d
6 makes it possible to interpret some of the complex spectra with superposed signals on the basis of the aromatic solvent induced shift (ASIS). 相似文献
609.
610.
A detailed understanding of the physical determinants of the ablation rate in multiple nanosecond laser pulses regime is of key importance for technological applications such as patterning and pulsed-laser deposition. Here, theoretical modeling is employed to investigate the ablation of thick metallic plates by intense, multiple nanosecond laser pulses. A new photo-thermal model is proposed, in which the complex phenomena associated to the ablation process are accounted for as supplementary terms of the classical heat equation. The pulsed laser ablation in the nanosecond regime is considered as a competition between thermal vapourization and melt ejection under the action of the plasma recoil pressure. Computer simulations using the photo-thermal model presented here and the comparison of the theoretical results with experiment indicate two different mechanisms that contribute to the decrease of the ablation efficiency. First, during the ablation process the vapour/plasma plume expanding above the irradiated target attenuates the laser beam that reaches the sample, leading to a marked decrease of the ablation efficiency. Additional attenuation of the laser beam incident on the sample is produced due to the heating of the plasma by the absorption of the laser beam into the plasma plume. The second mechanism by which the ablation efficiency decreases consists of the reduction of the incident laser intensity with the lateral area, and of the melt ejection velocity with the depth of the hole. 相似文献