Little G. T. for lp-lattice summing operators

2000 Mathematics Subject Classification: 46B28, 47D15.In this paper we introduce and study the lp-lattice summing operators in the category of operator spaces which are the analogous of p-lattice summing operators in the commutative case. We study some interesting characterizations of this type of operators which generalize the results of Nielsen and Szulga and we show that Λ l∞( B(H) ,OH) ≠ Λ l2( B( H) ,OH), in opposition to the commutative case

Reconstruction of the interface between two layered media using far field measurements

International audienceWe consider an inverse transmission scattering problem. This problem consists in determining an interface between two-layered media by far-field measurements. We prove that the interface is uniquely determined by the measurements of the far field pattern associated to incoming plane waves at a fixed frequency. For the reconstruction of the interface we solve a non linear integral equation using a truncated Newton-CG algorithm

Lifting dual tree complex wavelets transform

We describe the lifting dual tree complex wavelet transform (LDTCWT), a type of lifting wavelets remodeling that produce complex coefficients by employing a dual tree of lifting wavelets filters to get its real part and imaginary part. Permits the remodel to produce approximate shift invariance, directionally selective filters and reduces the computation time (properties lacking within the classical wavelets transform). We describe a way to estimate the accuracy of this approximation and style appropriate filters to attain this. These benefits are often exploited among applications like denoising, segmentation, image fusion and compression. The results of applications shrinkage denoising demonstrate objective and subjective enhancements over the dual tree complex wavelet transform (DTCWT). The results of the shrinkage denoising example application indicate empirical and subjective enhancements over the DTCWT. The new transform with the DTCWT provide a trade-off between denoising computational competence of performance, and memory necessities. We tend to use the PSNR (peak signal to noise ratio) alongside the structural similarity index measure (SSIM) and the SSIM map to estimate denoised image quality

A novel copper(II)-Schiff base complex containing pyrrole ring: Synthesis, characterization and its modified electrodes applied in oxidation of aliphatic alcohols

International audienceA new copper(II) complex Cu(II)-L containing N2O2 donor atoms has been prepared from 6-[3′-(N-pyrrol)propoxy]-2-hydroxyacetophenone and diaminoethane in the presence of copper acetate monohydrate. It was characterized by spectroscopic methods such as FT-IR, UV-vis, mass spectra, elemental analysis and cyclic voltammetry. The molecular structure of Cu(II)-L has also been confirmed by X-ray diffraction analysis. The electrochemical behavior of copper(II)-Schiff base complex containing pyrrol groups has been investigated in DMF and acetonitrile solutions using cyclic voltammetry. Thus, conducting polymeric films of polypyrrole were obtained on the surfaces of glassy carbon and ITO electrodes using copper(II) complex as monomer. The modified electrodes were electrochemically and morphologically characterized and their electrocatalytic properties in heterogeneous phase have also been investigated. The AFM studies show that the morphology of polypyrrole (PPy) films on ITO-electrodes depends on the number of cyclical scans. The electrocatalytic performances of this complex seem to be more efficient towards the electro-oxidation of isopropylic alcohol than any other kinds of alcohols such as methanol, ethanol and benzyl alcohol. The electro-reduction of carbon dioxide was also examined

3d and 4d coordination complexes and coordination polymers involving electroactive tetrathiafulvalene containing ligands

International audienceThe "through bond" approach has been recently developed to increase the interaction between the mobile π and localized d electrons in multifunctional molecular materials involving tetrathiafulvalene-based ligands. This article reviews the 3d and 4d coordination complexes and polymers elaborated from a library of tetrathiafulvalene derivatives containing ligands obtained recently in our group. The different synthetic ways of the complexes are highlighted as well as their chemical and physical properties

Etude mathematique des modes guides dans un milieu elastique a symetrie de revolution

Ce rapport est consacre a l'etude de la propagation d'ondes guidees dans un milieu elastique heterogene a symetrie de revolution. Ce probleme est ramene a l'etude spectrale d'une suite d'operateurs auto-adjoints. Nous etablissons des resultats tres fins qui prolongent et completent ceux precedemment obtenues dans [BDJ]. La plupart de ces resultats ont servi dans [C]. Ils constituent une base theorique pour une etude numerique des modes guides. Elle sera faite dans un rapport ulterieur par la methode des elements finis localises

Assessing the Efficiency of E-Teaching at Tertiary Level in Algeria during Covid-19 Pandemic: The Case of EFL Teachers

In Algeria, adopting e-teaching at the tertiary level could be quite challenging especially in the EFL context. In Fact, English courses in the different specialties - except English departments had been delivered exclusively online during both the first and second wave of the pandemic. This paper aimed to shed light on the efficiency of the online English courses from three angles: a. identifying the obstacles faced by the EFL teachers in course delivery, b. analyzing the students’ involvement, c. measuring the teaching achievement. In order to collect data, an online questionnaire was destined to 42 EFL teachers in Algeria. Results revealed that: first, the principal hurdles that EFL teachers encountered in course delivery refer to the lack of ICT training, internet quality, and the lack of technological tools. Second, despite the different strategies employed by our EFL teachers such as syllabus adaptation, online platforms, and both synchronous and asynchronous methods, students displayed less involvement and interest than expected. Finally, many EFL teachers couldn’t reach their teaching goals. The findings imply that more consideration should be given to our EFL teachers in terms of ICT training and digital resources for better courses delivery. Besides, teachers should find more adequate strategies to foster students’ motivation for successful e-learning application

On the sublinear operators factoring through L

Let 0<p≤q≤+∞. Let T be a bounded sublinear operator from a Banach space X into an Lp(Ω,μ) and let ∇T be the set of all linear operators ≤T. In the present paper, we will show the following. Let C be a positive constant. For all u in ∇T, Cpq(u)≤C (i.e., u admits a factorization of the form X→u˜Lq(Ω,μ)→MguLq(Ω,μ), where u˜ is a bounded linear operator with ‖u˜‖≤C, Mgu is the bounded operator of multiplication by gu which is in BLr+(Ω,μ) (1/p=1/q+1/r), u=Mgu∘u˜ and Cpq(u) is the constant of q-convexity of u) if and only if T admits the same factorization; This is under the supposition that {gu}u∈∇T is latticially bounded. Without this condition this equivalence is not true in general