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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

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)

Evaluation of optical propagation and radiation in optical waveguide using a numerical method

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Chinese Optics Letters 2014年第7期12卷 16-19页

作者： Mansour Bacha abderrahmane Belghoraf Space Technology Research Division Centre of Satellites Development Electronics Department University of Sciences and Technology of Oran Mohamed Boudiaf

We introduce a mathematical model based on a concept of intrinsic mode in order to analyse and synthesise optical wave propagation and radiation occurring in a non-uniform optical waveguide used in integrated optics as optical coupler. The model is based on numerical evaluation of electromagnetic wave by applying an intrinsic field integral to evaluate the field behaviour inside the optical waveguide. To analyse the field distribution inside the non-uniform waveguide and predict the beam propagation of optical energy involved in the propagation process, it is necessary to track the motion of any observation point along the tapered waveguide itself. Physically, the rays of the spectrum undergo reflections on the waveguide boundaries until the cut-off occurs and the phenomena of radiation begin. The numerical results show good agreement with those obtained by classical methods of evaluation used bv other works.

关键词： mode Evaluation of optical propagation and radiation in optical waveguide using a numerical method

Numerical evaluation of radiation and optical coupling occurring in optical coupler

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Chinese Optics Letters 2017年第2期15卷 35-39页

作者： Mansour Bacha abderrahmane Belghoraf Electronics Department University of Sciences and Technology of Oran Mohamed Boudiaf Oran M'Naouer BP 1505 Algeria Centre of Satellites Development Ibn Rochd USTO Oran BP 4065 Algeria

We present in this work a new mathematical model to analyze and evaluate optical phenomena occurring in the nonuniform optical waveguide used in integrated optics as an optical coupler. By introducing some modifications to the intrinsic integral, we perfectly assess the radiation field present in the adjacent medium of the waveguide and, thus, follow the evolution of the optical coupling from the taper thin film to the substrate and cladding until there is a total energy transfer. The new model that is introduced can be used to evaluate electromagnetic field distribution in three mediums that constitute any nonuniform optical couplers presenting great or low wedge angles.

关键词： Numerical evaluation of radiation and optical coupling occurring in optical coupler

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

Sequential extraction of Cs and Sr from Ain Oussera soils around Es-Salam research reactor facility

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Journal of Environmental Sciences 2015年第10期27卷 163-172页

作者： Abdelkader Bouzidi abderrahmane Ararem Djillali Imessaoudene Benalia Yabrir Centre de Recherche Nucléaire de Birine 17200 Ain OusseraAlgeria Laboratory of Exploration and Valorization of Steppic Ecosystems University of Djelfa

Four types of undisturbed soil in Ain Oussera region around the Es-Salam reactor facility,located in the south of Algiers, Algeria, at about 200 km, were artificially contaminated for one year with stable CsCl and SrCl2 in order to simulate an accidental release of these elements. This study was performed using sequential extraction procedure based on Shultz method and containing six fractions. The selectivity of the extraction protocol was confirmed by analyzing some elements（Ca, C, Fe, Mn, Si and Al） designed as indicators of the targeted phases. The obtained results showed an acceptable reproducibility, in view of the coefficients of variation that were in most cases less than 15%. The results revealed a clear proportional correlation between the extracted Cs and Sr in fractions for each soil and some of soils physicochemical properties. Organic matter appears to play an important role in the soil retention, particularly for Cs where the extracted percentage exceeds to 30% in whole soils. In contrast, strontium expresses a remarkable affinity for the fraction bound to carbonates. The obtained data also indicate that the availability of Cs in the four soils is less important compared to Sr availability. This is illustrated by the higher value of extracted Sr in the easily extractible phase, including the water-soluble and the exchangeable fraction.

关键词： Ain Oussera soils CsCl SrCl2 Sequential extraction Selectivity