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51.
52.
Abdellah Bnouhachem Muhammad Aslam Noor Zhang Hao 《Nonlinear Analysis: Theory, Methods & Applications》2009
In this paper, we suggest and analyze some new extragradient iterative methods for finding the common element of the fixed points of a nonexpansive mapping and the solution set of the variational inequality for an inverse strongly monotone mapping in a Hilbert space. We also consider the strong convergence of the proposed method under some mild conditions. Several special cases are also discussed. Results proved in this paper may be viewed as improvement and refinement of the previously known results. 相似文献
53.
Abdellah El Kinani 《Rendiconti del Circolo Matematico di Palermo》2008,57(2):229-238
We endow any proper A-convex H*-algebra (E, τ) with a locally pre-C*-topology. The latter is equivalent to that introduced by the pre C*-norm given by Ptàk function when (E, τ) is a Q-algebra. We also prove that the algebra of complex numbers is the unique proper locally A-convex H*-algebra which is barrelled and Q-algebra.
相似文献
54.
Rafael?MartíEmail author Francisco?Montes Abdellah?El-Fallahi 《Journal of Heuristics》2005,11(3):219-232
Different methodologies have been introduced in recent years with the aim of approximating unknown functions. Basically, these methodologies are general frameworks for representing non-linear mappings from several input variables to several output variables. Research into this problem occurs in applied mathematics (multivariate function approximation), statistics (nonparametric multiple regression) and computer science (neural networks). However, since these methodologies have been proposed in different fields, most of the previous papers treat them in isolation, ignoring contributions in the other areas. In this paper we consider five well known approaches for function approximation. Specifically we target polynomial approximation, general additive models (Gam), local regression (Loess), multivariate additive regression splines (Mars) and artificial neural networks (Ann).Neural networks can be viewed as models of real systems, built by tuning parameters known as weights. In training the net, the problem is to find the weights that optimize its performance (i.e. to minimize the error over the training set). Although the most popular method for Ann training is back propagation, other optimization methods based on metaheuristics have recently been adapted to this problem, outperforming classical approaches. In this paper we propose a short term memory tabu search method, coupled with path relinking and BFGS (a gradient-based local NLP solver) to provide high quality solutions to this problem. The experimentation with 15 functions previously reported shows that a feed-forward neural network with one hidden layer, trained with our procedure, can compete with the best-known approximating methods. The experimental results also show the effectiveness of a new mechanism to avoid overfitting in neural network training. 相似文献
55.
Abdellah Maalouf Roger Bouard 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1987,38(4):522-541
Résumé On étudie par voies numérique et expérimentale l'écoulement plan engendré par la translation uniforme en régime de Stokes d'une coque poreuse cylindrique à mi-distance entre deux parois parallèles. On donne des résultats fiables et détaillés concernant le champ hydrodynamique en formulant avec précision les conditions de raccordement aux interfaces entre le milieu poreux et le milieu fluide.
The two-dimensionnal flow induced by the uniform translation of a porous shell cylinder midway between two parallel plane walls is investigated, for the Stokes regime, both numerically and experimentally. Reliable and detailed results relative to the hydrodynamic field are given formulating the conditions of junction between porous and fluid media.相似文献
56.
The volumes of mixing for the systems cyclopentane + cyclohexane, cyclopentane + cycloheptane, cyclohexane + cycloheptane (at 20°C), and cyclopentane + cyclooctane, cyclohexane + cyclooctane, cycloheptane + cyclooctane (at 30 °C) have been measured with a dilatometer. All systems show volume contractions, except the first. The energies of mixing are also given. They vary from 7 to 55 J/mol for equimolar solutions. 相似文献
57.
Nozzle flow separation 总被引:2,自引:0,他引:2
58.
Mustapha Aitali My Youssef Ait Itto Aisa Hasnaoui Abdelkhalek Riahi Abdellah Karim Santiago García‐Granda Angel Gutirrez‐Rodríguez 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e315-e316
The novel title ruthenium(II) complex, [RuCl(C10H14)(C10H10N3OS)], was synthesized from the reaction of 1,2,4‐triazepine, a new class of bidentate ligands, with [Ru(p‐cymene)Cl2]2. The 1,2,4‐triazepine ligand is coordinated to the metal centre through the N‐4 and S atoms, forming a four‐membered chelate ring. This is the first structural example of a transition metal complex containing a 1,2,4‐triazepine ligand. 相似文献
59.
Benyoub Nassima Barça Abdelhafid Selâdji Fawzia Benhamou Abdellah Debab Abdelkader 《Research on Chemical Intermediates》2021,47(10):4311-4331
Research on Chemical Intermediates - The single and binary adsorption of two anionic dyes Acid Yellow 17 (AY17) and Naphtol Green B (NGB) onto N–N–Dimethyl-n-octylamine (DMOA) modified... 相似文献
60.
Abdellah Lacherai Ahmed Mazzah 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1441-1456
The reaction of bis(dichlorophosphoryl)imide HN(P(O)Cl 2 ) 2 1 , with N,N-bis(2-chloroethyl)amine HN(CH 2 CH 2 Cl) 2 (bCEA), has been studied in order to synthesize Phosphorus-Nitrogen derivatives which present anti-tumoral activity. It has been possible to show the formation of the mono 2 , di 3 and tetrasubstituted 4 derivatives as well as the existence of diastereoisomers for 2 and 3 . The combined use of NMR ( 31 P, 13 C) and mass spectrometry has allowed us to show the instability of the tetrasubstituted derivative wich is transformed to the O-alkylated compound 4a with elimination of HCl. We studied also the cosubstitution reactions of 1 by HN(CH 2 CH 2 Cl) 2 and ammonia on the one hand, HN(CH 2 CH 2 Cl) 2 and glycine ethyl ester on the other hand. Spectroscopic studies of the resulting products revealed the involvement of N-alkylation reactions leading to 6 and 7 . The study of the antitumoral activity of these compounds was undertaken. Only the phosphazene derivative 2 which contains a bifunctionnal alkylating agent exhibited a moderate anti-tumoral activity. 相似文献