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Advances in Chemical Engineering and Science 2018年第1期8卷 1-10页

作者： Souheila Chamekh abderrahmane bouabellou Thin Films and Interfaces Laboratory University of Constantine Constantine Algeria

The work reported in this paper aims at a better understanding of the magnetic doping effects on the structural and electrical properties for a series of YBa2(Cu1-xCox)3O7-δ ceramics. The Co doped YBa2Cu3O7-δ are (YBCO) prepared by conventional solid state reaction method and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), differential thermal analysis (DTA) and resistivity measurements. The crystal lattice parameters are found to change due to the cobalt doping and tendency to a structure phase transition from orthorhombic to tetragonal, which is confirmed by the decrease of the degree of orthorhombicity. The morphology examination with SEM revealed gradual increases of grain size with x = 0.02 Co, a high porosity is observed in the doped samples compared to the pure one. The decomposition temperature of YBCO is pushed from temperatures above 975°C to lower temperatures of 945°C. The resistivity measurements of doped samples with x = 0.04 and 0.06;shows a deviation in from T-linear behavior due to the opening of a pseudogap.

关键词： YBCO Doped Co Electrical Properties Phase Transition High Tc Superconductivity

Effect of Substrates on the Properties of ZnO Thin Films Grown by Pulsed Laser Deposition

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Advances in Materials Physics and Chemistry 2013年第4期3卷 209-213页

作者： Adel Taabouche abderrahmane bouabellou Fouad Kermiche Faouzi Hanini Sarah Menakh Yacine Bouachiba Tahar Kerdja Chawki Benazzouz Mohamed Bouafia Saad Amara Advanced Technology Development Center (CDTA) Baba-Hassen Algiers Algeria Center CRNA 2 Bd Franz Fanon Algiers Algeria Laboratory of Applied Optics Ferhat Abbas University Setif Algeria Thin Films and Interfaces Laboratory University of Constantine Constantine Algeria

Polycrystalline zinc oxide (ZnO) thin films have been deposited at 450°C onto glass and silicon substrates by pulsed laser deposition technique (PLD). The used source was a KrF excimer laser (248 nm, 25 ns, 5 Hz, 2 J/cm2). The effects of glass and silicon substrates on structural and optical properties of ZnO films have been investigated. X-ray diffraction patterns showed that ZnO films are polycrystalline with a hexagonal wurtzite—type structure with a strong (103) orientation and have a good crystallinity on monocrystalline Si(100) substrate. The thickness and compositional depth profile were studied by Rutherford Backscattering spectrometry (RBS). The average transmittance of ZnO films deposited on glass substrate in the visible range is 70%.

关键词： ZnO Thin Films PLD Silicon X-Ray Diffraction Optical Transmittance RBS

Coupled Lamé System with a Viscoelastic Term and a Strong Discrete Time Delays

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Journal of Partial Differential Equations 2024年第2期37卷 121-134页

作者： BENIANI abderrahmane Engineering and Sustainable Development Laboratory Faculty of Science and TechnologyUniversity of Ain TemouchentAin Temouchent 46000Algeria

In this paper,we consider a coupled Lamé system with a viscoelastic damping in the first equation and two strong discrete time *** prove its existence by using the Faedo-Galerkin method and establish an exponential d... 详细信息

关键词： Lamésystem coupled system Lyapunov function delay term

Sausage Finger Revealed a Bone Sarcoidosis

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International Journal of Dermatology and Venereology 2024年第3期7卷 176-177页

作者： Fatima-Zahra Agharbi abderrahmane Albouzidi Soumiya Chiheb Department of Dermatology Sheikh Khalifa HospitalFaculty of MedicineMohamed VI University of Health SciencesCasablanca 82403Morocco.

Dear Editor,Sarcoidosis is a systemic inflammatory disease of unknown etiology that is characterized by the forma-tion of a giganto-cellular epithelioid granuloma with-out caseous necrosis infiltrating the various *** condition most frequently involves the mediastinal and pulmonary regions,while bone involvement is rare and affects only 1.0%to 13.0%of patients with sarcoid-osis.1 We report a case of an isolated bone sarcoidosis presenting as bull’s finger.

关键词： involvement Sarcoidosis etiology

Predicting an Optimal Virtual Data Model for Uniform Access to Large Heterogeneous Data

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Data Intelligence 2024年第2期6卷 504-530页

作者： Chahrazed B.Bachir Belmehdi abderrahmane Khiat Nabil Keskes LabRI-SBA Enterprise Information SystemsESI-SBA InstituteFraunhofer IAISAlgeriaGermany

The growth of generated data in the industry requires new efficient big data integration approaches for uniform data access by end-users to perform better business *** virtualization systems,including Ontology-Based Data Access(ODBA)query data on-the-fly against the original data sources without any prior data *** approaches by design use a fixed model e.g.,TABULAR as the only Virtual Data Model-a uniform schema built on-the-fly to load,transform,and join relevant *** other data models,such as GRAPH or DOCUMENT,are more flexible and,thus,can be more suitable for some common types of queries,such as join or nested *** queries are hard to predict because they depend on many criteria,such as query plan,data model,data size,and *** address the problem of selecting the optimal virtual data model for queries on large datasets,we present a new approach that(1)builds on the principal of OBDA to query and join large heterogeneous data in a distributed manner and(2)calls a deep learning method to predict the optimal virtual data model using features extracted from SPARQL ***-implementation of our approach currently leverages state-of-the-art Big Data technologies,Apache-Spark and Graphx,and implements two virtual data models,GRAPH and TABULAR,and supports out-of-the-box five data sources models:property graph,document-based,e.g.,wide-columnar,relational,and tabular,stored in Neo4j,MongoDB,Cassandra,MySQL,and CSV *** experiments show that our approach is returning the optimal virtual model with an accuracy of 0.831,thus,a reduction in query execution time of over 40%for the tabular model selection and over 30%for the graph model selection.

关键词： Data Virtualization Big Data OBDA Deep Learning

Extra Renal Rhabdoid Tumor: A Rare Cause of Congenital Soft Tissue Tumor

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Open Journal of Pediatrics 2024年第3期14卷 579-584页

作者： Tazi Charki Mohammed Akammar Amal Dardar Hajar Abdellaoui Hicham Atarraf Karima Boubou Meryem Afifi Moulay abderrahmane Department of Pediatric Orthopedic and Traumatology University Hospital Hassan II Fez Morocco The Faculty of Medicine and Pharmacy Sidi Mohamed Ben Abdellah University Fez Morocco Department of Radiology University Hospital Hassan II Fez Morocco

Rhabdoid tumors (RTs) are a well-defined entity in the kidney or central nervous system of infants or children. However, soft-tissue involvement is uncommon. It’s an exceptional neonatal tumor of soft tissue. The imaging characteristics of this tumor are not specific. Biopsy allows diagnosis;the histomorphological characteristics of rhabdoid tumors, their immunoreactivity to epithelial markers and vimentin, and the INI-1 loss are important tools for diagnosis. RT tumors are aggressive and have a rapidly fatal clinical course in most cases. Despite multidisciplinary therapy, the survival rate is very low. We report a rare case occurring in a male neonate who presents at birth with a voluminous right axillary mass. A CT scan showed a well-limited tumor mass with lobulated contours. An ultrasound-guided biopsy was performed on day 8, showing the morphology and immunoprofile of RT. The mass showed rapid growth. The child was admitted for respiratory distress at 3 weeks. A thoraco-abdominal CT showed an increase in the size of the mass with the appearance of multiple lymph nodes and pleural, hepatic, and renal metastases. The child died two days later.

关键词： Congenital Rhabdoid Tumor Soft Tissue Diagnosis Immunohistochemistry INI-1

Active Queue Management Exploiting the Rate Information in TCP-IP Networks

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 223-231页

作者： abderrahmane Boudi Malik Loudini Laboratoire de la Communication dans les Systemes Informatiques Ecole nationale Superieure d'Informatique ESI Algiers 16309 Algeria IEEE

In this paper, we propose a new mechanism called explicit rate notification(ERN) to be used in end-to-end communications. The ERN scheme encodes in the header of transmission control protocol(TCP) packets information about the sending rate and the round trip time(RTT) of the flows. This new available information to the intermediate nodes(routers) is used to improve fairness, increase utilization, decrease the number of drops, and minimize queueing delays. Thus, it induces a better management of the queue. A comparison of our scheme with preexistent schemes, like the explicit congestion notification scheme, shows the effectiveness of the proposed mechanism.

关键词： Active queue management congestion control fairness transmission control protocol(TCP)

ISOGENOUS OF THE ELLIPTIC CURVES OVER THE RATIONALS

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Journal of Computational Mathematics 2002年第4期20卷 337-348页

作者： abderrahmane Nitaj Mathematik Universitat des SaarlandesPostfach 15 1150D-66041SaarbrockenGermany

An elliptic curve is a pair (E,O), where E is a smooth projective curve of genus 1 and O is a point of E, called the point at infinity. Every elliptic curve can be given by a Weierstrass equationE:y2+a1xy+a3y=x2+a2x2+a4x+*** Q be the set of rationals. E is said to be dinned over Q if the coefficients ai, i = 1, 2, 3, 4, 6 are rationals and O is defined over *** E/Q be an elliptic curve and let E(Q)tors be the torsion group of points of E defined over Q. The theorem of Mazur asserts that E(Q)tors is one of the following 15 groupsWe say that an elliptic curve E'/Q is isogenous to the elliptic curve E if there is an isogeny, i.e. a morphism φ: E → E' such that φ(O) = O, where O is the point at *** give an explicit model of all elliptic curves for which E'(Q)tors is in the form Z/mZ where m = 9, 10, 12 or Z/2Z × Z/2mZ where m = 4, according to Mazur's theorem. Morever, for every family of such elliptic curves, we give an explicit model of all their isogenous curves with cyclic kernels consisting of rational points.

关键词： Courbe elliptique Isogenie

Comparative characterisation of conventional and textured 11􀯓kV insulators using the rotating wheel dip test

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High Voltage 2020年第6期5卷 739-746页

作者： Adnan Krzma Maurizio Albano abderrahmane Haddad Advanced High Voltage Engineering Research Centre School of EngineeringCardiff UniversityWalesUK Department of Electrical and Computer Engineering Faculty of EngineeringElmergib UniversityAl-KhomLibya

Surface tracking and erosion is an irreversible degradation occurring on the insulator surface, and this can ultimately lead to failure of the insulator. Polymeric materials such as silicone rubber have many advantages;including a superior hydrophobic surface. However, polymers are exposed to ageing and degradation resulting from electrical and environmental stresses. The rotating wheel dip test is adopted to conduct a comparative study of surface conduction on the two insulators. A conventional design has been selected and compared with insulators having textured surface. Monitoring of the shed surface and insulator trunk using an IR camera were carried out to assess the temperature distribution along insulator profiles. A spatial analysis was also performed to identify key features of the two designs. Localised surface conductance measurements are proposed in this study. This helps to understand and distinguish the trends of conductance and its distribution on each surface, helping to predict the future surface degradation associated to each design。

关键词： insulator rotating character

Recognition of Offline Handwritten Arabic Words Using a Few Structural Features

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Computers, Materials & Continua 2021年第3期66卷 2875-2889页

作者： abderrahmane Saidi Abdelmouneim Moulay Lakhdar Mohammed Beladgham Department of Electrical Engineering Laboratory:LTITTahri Mohammed UniversityBechar08000Algeria

Handwriting recognition is one of the most significant problems in pattern recognition,many studies have been proposed to improve this recognition of handwritten text for different ***,Fewer studies have been done for the Arabic language and the processing of its texts remains a particularly distinctive problem due to the variability of writing styles and the nature of Arabic scripts compared to other *** present paper suggests a feature extraction technique for offlineArabic handwriting recognition.A handwriting recognition system for Arabic words using a few important structural features and based on a Radial Basis Function(RBF)neural networks is *** methods of feature extraction are central to achieve high recognition *** proposed methodology relies on a feature extraction technique based on many structural characteristics extracted from the word skeleton(subwords,diacritics,loops,ascenders,and descenders).In order to reach our purpose,we built our own word database and the proposed system has been successfully tested on a handwriting database of Algerian city names(wilayas).Finally,a simple classifier based on the radial basis function neural network is presented to recognize certain words to verify the reliability of the proposed feature *** experiments on some images of the benchmark IFN/ENIT database show that the proposed system improves recognition and the results obtained are indicative of the efficiency of our technique.

关键词： Offline Arabic handwriting recognition preprocessing feature extraction structural features RBF neural network