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Intensity Distribution of the Finite Olver Beams through a Paraxial ABCD Optical System with an Aperture of Basis Annular Aperture

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Optics and Photonics Journal 2015年第12期5卷 354-368页

Based on the Collins diffraction formula and by means of the expansion of a hard aperture function into a finite sum of complex Gaussian functions, two analytical approaches of the Finite Olver beams (FOBs) passing through a paraxial ABCD optical system with a circular annular aperture or a rectangular one are developed in this paper. The propagation properties of the FOBs through an unapertured ABCD optical system or through this last with a circular (or rectangular) aperture or a circular (or rectangular) black screen are deduced, from the main results, as particular cases. Also, the characteristics of Finite ordinary Airy beam passing through the all considered optical systems are derived here that correspond to zeroth-order of the FOBs. According to the predicted formulas, computer simulation examples are given to deepen the understanding of the characteristics of the FOBs passing through some optical systems of annular aperture basis.

关键词： Diffraction Finite Olver Beams Airy Beams ABCD Optical System Circular Annular Aperture Rectangular Annular Aperture Circular Black Screen Rectangular Black Screen

Radiation Forces on a Dielectric Sphere Produced by Finite Olver-Gaussian Beams

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Optics and Photonics Journal 2015年第12期5卷 344-353页

作者： Salima Hennani Lahcen Ez-zariy abdelmajid belafhal Laboratory of Nuclear Atomic and Molecular Physics Department of Physics Faculty of Sciences Choua&#239 b Doukkali University El Jadida Morocco

In this work, we use the analytical expression of the propagation of Finite Olver-Gaussian beams (FOGBs) through a paraxial ABCD optical system to study the action of radiation forces produced by highly focused FOGBs on a Rayleigh dielectric sphere. Our numerical results show that the FOGBs can be employed to trap and manipulate particles with the refractive index larger than that of the ambient. The radiation force distribution has been studied under different beam widths. The trapping stability under different conditions is also analyzed.

关键词： Finite Olver-Gaussian Beams Radiation Forces Scattering Force Gradient Force Rayleigh Dielectric Sphere

Propagation Characteristics of Airy-Gaussian Beams Passing through a Misaligned Optical System with Finite Aperture

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Optics and Photonics Journal 2014年第11期4卷 325-336页

作者： Lahcen Ez-Zariy Salima Hennani Hamid Nebdi abdelmajid belafhal Laboratory of Nuclear Atomic and Molecular Physics Department of Physics Faculty of Sciences Chouaib Doukkali University El Jadida Morocco

Propagation characteristics of finite Airy-Gaussian beams through an apertured misaligned first-order ABCD optical system are studied. In this work, the generalized Huygens-Fresnel diffraction integral and the expansion of the hard aperture function into a finite sum of complex Gaussian functions are used. The propagation of Airy-Gaussian beam passing through: an unapertured misaligned optical system, an apertured aligned ABCD optical system and an unapertured aligned ABCD optical system are derived here as particular cases of the main finding. Some numerical simulations are performed in the paper.

关键词： Airy-Gaussian Beams Huygens-Fresnel Diffraction Integral Aperture Misalignment

Theoretical Introduction and Generation Method of a Novel Nondiffracting Waves: Olver Beams

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Optics and Photonics Journal 2015年第7期5卷 234-246页

作者： abdelmajid belafhal Lahcen Ez-Zariy Salima Hennani Hamid Nebdi Laboratory of Nuclear Atomic and Molecular Physics Department of Physics Faculty of Sciences Choua&#239 b Doukkali University El Jadida Morocco

In this paper, we introduce a new class of scalar nondiffracting Helmholtz-equation solution. We demonstrate that this novel wave-equation solution has some specific orders;among these ordinary Airy beams which are regarded as the zeroth order. Moreover, a general expression of these novel beams, which are named Olver Beams and referred to OBs, is developed. The zeroth and the first high orders of the incident OBs are presented theoretically and numerically in this paper. Yet, based on a computer generated holograms method, the generation’s masks of the Finite OBs in first orders are given in this work. Also, the incident transverse intensity distribution in 1-D and 2-D of the first orders of OBs is performed.

关键词： Olver Beams Airy Beams Fourier Transform Masks

Propagation of Modified Bessel-Gaussian Beams in a Misaligned Optical System

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Optics and Photonics Journal 2012年第4期2卷 318-325页

作者： Lahcen Ez-Zariy Hamid Nebdi El Hassane Bentefour abdelmajid belafhal Laboratoire de Physique Nucleaire Atomique et Moleculaire Departement de PhysiqueFaculte des SciencesUniversite Chouaib DoukkaliEl JadidaMorocco LigthOnKnowledge Foundation ChicagoUSA

The formalism of generalized diffraction integral for paraxial misaligned optical systems is used to investigate the propagation of the Modified Bessel-Gaussian (MBG) beam through a misaligned thin lens. The properties of the propagation of MBG beam traveling through this misaligned ABCD optical system are discussed. A special case of misaligned circular thin lens is illustrated analytically and numerically. The shape of the MBG beam at the exit of the misaligned optical system is unchanged;however the center of the beam is shifted from the propagation axis in correlated manner with the design parameters of the optical system.

关键词： Generalized Diffraction Integral Modified Bessel-Gaussian Beams Propagation Misaligned ABCD Optical Systems Circular Thin Lens

Propagation of Modified Bessel-Gaussian Beams in a Misaligned Optical System

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Dynamics of Plate Equations with Memory Driven by Multiplicative Noise on Bounded Domains

Optics and Photonics Journal（光学与光子学期刊） 2012年第4期

作者： Lahcen Ez-Zariy Hamid Nebdi El Hassane Bentefour abdelmajid belafhal

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1492-1521页

作者： Mohamed Y. A. Bakhet abdelmajid Ali Dafallah Jing Wang Qiaozhen Ma Fadlallah Mustafa Mosa Ahmed Eshag Mohamed Paride O. Lolika Makur Mukuac Chinor School of Mathematics University of Juba Juba South Sudan Department of Mathematics Faculty of Petroleum and Hydrology Engineering Alsalam University Almugled Sudan College of Mathematics and Statistics Northwest Normal University Lanzhou China Department of Mathematics and Physics Faculty of Education University of Kassala Kassala Sudan Department of Mathematics School of Education University of Juba Juba South Sudan

This article examines the dynamics for stochastic plate equations with linear memory in the case of bounded domain. We investigate the existence of solutions and bounded absorbing set by using the uniform pullback attractors on the tails estimates, and the asymptotic compactness of the random dynamical system is proved by decomposition method, and then we obtain the existence of a random attractor.

关键词： Plate Equations Random Attractors Memory Term Dynamical Systems

The Physiological Mechanisms Underlying N_(2)-Fixing Common Bean(Phaseolus vulgaris L.)Tolerance to Iron Deficiency

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Phyton-International Journal of Experimental Botany 2023年第7期92卷 2133-2150页

作者： abdelmajid Krouma Faculty of Sciences and Techniques University of KairouanSidi Bouzid9100Tunisia Laboratory of Ecosystems and Biodiversity in Arid Land of Tunisia Faculty of SciencesUniversity of SfaxSfaxTunisia

Iron is an essential element for plants as well as all living organisms,functioning in various physiological and biochemical processes such as photosynthesis,respiration,DNA synthesis,and N2 *** the soil,Fe bioavailability is extremely low,especially under aerobic conditions and at high pH *** contrast,plants with nodules on their roots that fix atmospheric nitrogen need much more *** highlight the physiological traits underlying the tolerance of N2-fixing common bean to iron deficiency,two genotypes were hydroponically cultivated in a greenhouse:Coco nain(CN)and Coco blanc(CB).Plants were inoculated with an efficient strain of Rhizobium tropici,CIAT899,and received a nutrient solution added with 0μM Fe(severe Fe deficiency,SFeD),5μM Fe(moderate Fe deficiency,MFeD)or 45μM Fe(control,C).Several physiological parameters related to photosynthesis and symbiotic nitrogen fixation were then *** deficiency significantly reduced whole plant and nodule growth,chlorophyll biosynthesis,photosynthesis,leghemoglobin(LgHb),nitrogenase(N2ase)activity,nitrogen,and Fe nutrition,with some genotypic *** compared to CB,CN maintained better Fe allocation to shoots and nodules,allowing it to preserve the integrity of its photosynthetic and symbiotic apparatus,thus maintaining the key functional traits of the plant metabolism(chlorophyll biosynthesis and photosynthesis in shoots,leghemoglobin accumulation,and nitrogenase activity in root nodules).Plant growth depends on photosynthesis,which needs to be supplied with sufficient iron and *** deficiency stress index(FeD-SI)and Fe use efficiency(FeUE)are two physiological traits of tolerance that discriminated the studied genotypes.

关键词： traits metabolism apparatus

A New Method for Sentiment Analysis Using Contextual Auto-Encoders

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Journal of Computer Science & Technology 2018年第6期33卷 1307-1319页

作者： Hanen Ameur Salma Jamoussi abdelmajid Ben Hamadou Multimedia Information Systems and Advanced Computing Laboratory Sfax University Sfax Technopole Sfa 3021 Tunisia

Sentiment analysis, a hot research topic, presents new challenges for understanding users＇ opinions and judg-ments expressed online. They aim to classify the subjective texts by assigning them a polarity label. In this paper, weintroduce a novel machine learning framework using auto-encoders network to predict the sentiment polarity label at theword level and the sentence level. Inspired by the dimensionality reduction and the feature extraction capabilities of theauto-encoders, we propose a new model for distributed word vector representation ＂PMI-SA＂ using as input pointwise-mutual-information ＂PMI＂ word vectors. The resulted continuous word vectors are combined to represent a sentence. Anunsupervised sentence embedding method, called Contextual Recursive Auto-Encoders ＂CoRAE＂, is also developed forlearning sentence representation. Indeed, CoRAE follows the basic idea of the recursive auto-encoders to deeply composethe vectors of words constituting the sentence, but without relying on any syntactic parse tree. The CoRAE model consistsin combining recursively each word with its context words （neighbors＇ words： previous and next） by considering the wordorder. A support vector machine classifier with fine-tuning technique is also used to show that our deep compositionalrepresentation model CoRAE improves significantly the accuracy of sentiment analysis task. Experimental results demon-strate that CoRAE remarkably outperforms several competitive baseline methods on two databases, namely, Sanders twittercorpus and Facebook comments corpus. The CoRAE model achieves an efficiency of 83.28% with the Facebook dataset and97.57% with the Sanders dataset.

关键词： sentiment analysis recursive auto-encoder stacked auto-encoder pointwise mutual information deep embed-ding representation