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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

ELASTIC MEMBRANE EQUATION WITH MEMORY TERM AND NONLINEAR BOUNDARY DAMPING:GLOBAL EXISTENCE,DECAY AND BLOWUP OF THE SOLUTION

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Acta Mathematica Scientia 2013年第1期33卷 84-106页

作者： abderrahmane ZARA Nasser-eddine TATAR Salem ABDELMALEK Depatment of Mathematics and Informatic Cheikh El Arbi Tébessi University12002 TébessaAlgeria Depatment of Mathematics and Statistics King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Depatment of Mathematics College of SciencesYanbuTaibah UniversitySaudi Arabia

In this paper we consider the Elastic membrane equation：with memory term and nonlinear boundary damping： Under some appropriate assumptions on the relaxation function h and with certain initial data, the global existence of solutions ：and a general decay for the energy are established using the multiplier technique. Also, ＇we show that a nonlinear source of polynomial type is able to force solutions to blow up in finite time even in presence of a nonlinear damping.

关键词： elastic membrane equation global existence boundary damping boundarysource general decay blowup

A GENERAL DECAY AND OPTIMAL DECAY RESULT IN A HEAT SYSTEM WITH A VISCOELASTIC TERM

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Acta Mathematica Scientia 2019年第2期39卷 618-626页

作者： abderrahmane YOUKANA Salim A.MESSAOUDI Aissa GUESMIA Department of Mathematics University of Batna Department of Mathematics and Statistics KFUPM Elie Cartan Institute of Lorraine Universite de Lorraine Department of Mathematics and Statistics King Fahd University of Petroleum and Minerals

We consider a quasilinear heat system in the presence of an integral term and establish a general and optimal decay result from which improves and generalizes several stability results in the literature.

关键词： heat equation viscoelastic general decay optimal

5-Nitro-1,2,4-triazole-3-one:A Review of Recent Advances

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含能材料 2019年第4期27卷 326-347,I0007页

作者： Sabrina Hanafi Djalal Trache Slimane Abdous Zineddine Bensalem abderrahmane Mezroua UER Procedes Energetiques Ecole Militaire Polytechnique

The 3?Nitro?1,2,4?triazole?5?one(NTO)is a high energy density materials of keen interest for both commercial and scientific worlds owing to its reduced sensitivity,better thermal stability and high performances. It plays a significant role to replace the current energetic ingredients. In this review,we summarize various strategies involved in the synthesis of NTO as well as the existing approaches to tailor its particle morphology and sizes. The most prominent properties of NTO,such as insensitivity and performance,which are usually required to produce efficient formulations,have been concisely discussed. In addition,this overview reports on some newer forms of NTO including derivatives and co?crystals available in the literature,which can enhance the NTO features and extend its applications. The advantages and shortcomings of various NTO forms for specific and potential use are also highlighted together with the attempts made to overcome these issues. Therefore,efforts will certainly continue to improve characteristics and performances of NTO either by chemical modification or by co?crystallization in order to produce promising formulations for widespread applications in the near future.

关键词： Triazolone 3-nitro-1,2,4-triazole-5-one(NTO) synthesis properties particle morphology derivatives co-crystals applications

A new experimental way for the monitoring of the real/equivalent inservice- time of double base rocket propellant by coupling VST and PCA

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Defence Technology（防务技术） 2021年第2期17卷 440-449页

作者： Salim Chelouche Djalal Trache Ilyas Maamache Ahmed Fouzi Tarchoun Kamel Khimeche abderrahmane Mezroua UER Procedes Energetiques Ecole Militaire PolytechniqueEMPBP 17 Bordj-El-Bahri16046AlgiersAlgeria

The assessment of the real in-service-time(RIST)and the equivalent in-service-time(EIST)of double base rocket propellants(DBRPs)is of utmost importance for the safe storage and use of weapon systems as well as the efficiency of the accelerated aging *** this work,four DBRPs with similar chemical composition and different natural aging have been artificially aged at T?338.65 K for 4 months with sampling every 30 *** unaged and artificially aged samples have been investigated by vacuum stability test(VST)at five isothermal temperatures(T?333.15 K,343.15 K,353.15 K,363.15 K,and 373.15 K).The volume of the evolved gases in VST was found to decrease with natural/artificial ***,the VST data were treated and subjected to principal component analysis(PCA).The results showed excellent discrimination of the DBRP samples according to their stability thermal *** of the variance was described by the first principal component(PC1)whose scores were linearly correlated with the natural aging durations when PCA is applied on VST data obtained at T?363.15 *** light of the obtained results,a new experimental way for the estimation of the real/equivalent IST was proposed,which takes into account the impact of the natural aging of the *** approach predicts successfully the RIST of two similar DBRPs with a relative deviation of less than 2%.At the specific heating temperature T?338.65 K,the developed model provides more conceivable EIST values,with asymptotic behavior against artificial aging duration evolution,thus overcoming some shortcomings of the common generalized van’t Hoff formula(GvH).

关键词： Chemometrics van’t hoff rule Natural aging Artificial aging Stability Storage

AN ASYMPTOTIC BEHAVIOR AND A POSTERIORI ERROR ESTIMATES FOR THE GENERALIZED SCHWARTZ METHOD OF ADVECTION-DIFFUSION EQUATION

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Acta Mathematica Scientia 2018年第4期38卷 1227-1244页

作者： Salah BOULAARAS Mohammed Said TOUATI BRAHIM Smail BOUZENADA abderrahmane ZARAI Department of Mathematics College of Sciences and Arts Al-Ras Qassim University Kingdom of Saudi Arabia Laboratory of Fundamental and Applied Mathematics of Oran (LMFAO) University of Oran 1 Ahmed Benbella Oran Algeria Department of Mathematics and Computer Science Larbi Tebessi University 12002 Tebessa Algeria

In this paper, a posteriori error estimates for the generalized Schwartz method with Dirichlet boundary conditions on the interfaces for advection-diffusion equation with second order boundary value problems are proved by using the Euler time scheme combined with Galerkin spatial method. Furthermore, an asymptotic behavior in Sobolev norm is de- duced using Benssoussau-Lions＇ algorithm. Finally, the results of some numerical experiments are presented to support the theory.

关键词： a posteriori error estimates GODDM advection-diffusion Galerkin method Benssoussan-Lions' algorithm

Grain Design and Optimization Method of A Single Chamber Multi-thrust Solid Rocket Motor

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Grain Design and Optimization Method of A Single Chamber Mul...

作者： Zanat abderrahmane 北京理工大学

学位级别：硕士

装药的几何形状的确定是固体火箭发动机设计的一个重要环节,装药的几何形状的计算精度决定了发动机性能预示精度。只有确定了发动机装药结构,才能在发动机设计中获得所需要的燃面和弹道性能。本文中,针对不同类型的固体推进剂,设计了几... 详细信息

装药的几何形状的确定是固体火箭发动机设计的一个重要环节,装药的几何形状的计算精度决定了发动机性能预示精度。只有确定了发动机装药结构,才能在发动机设计中获得所需要的燃面和弹道性能。本文中,针对不同类型的固体推进剂,设计了几种插槽(径向和纵向)。本文的研究目的是优化单室多推力固体火箭发动机中药柱的开槽尺寸。首先将自变量为药柱开槽的几何尺寸的数学函数设置为目标函数,然后设置优化条件和初始参数,用MATLAB编程得出参数(槽长,槽深和槽弧半径)的最优解,最后将该优化方法应用到星形药柱上,并计算出弹道参数。

关键词：固体火箭发动机SRM 槽主要尺寸优化目标函数单腔多的推力

First‐mode of negative streamers:Inception at liquid/solid interfaces

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High Voltage 2021年第6期6卷 1069-1078页

作者： David Ariza abderrahmane Beroual Ralf Methling Sergey Gortschakow Harold R.Chamorro School of Electrical Engineering KTH Royal Institute of TechnologyStockholmSweden Ecole Centrale de‐Lyon Ampère CNRS UMR 5005EcullyFrance Leibniz Institute for Plasma Science and Technology INP GreifswaldGermany

An experimental study of the inception of the first‐mode negative streamer at liquid/solid interfaces is presented in this *** study is performed with a point‐plane configuration under square high voltage *** electrode configuration is immersed in mineral oil and the liquid/solid interface is assembled in contact with the point electrode or in its *** polymers and two impregnated papers have been tested as solids of the liquid/solid ***,it is possible to compare the influence of different parameter of the solid and the interface on the streamer *** example:Permittivity,solid surface roughness,chemical composition,*** has been observed that streamer inception voltages at interfaces with solids of higher permittivity to that of the mineral oil are statistically ***,streamer inception voltages of streamer initiated free in the oil(no liquid/solid interface)are similar to that of the inception voltage of cases with solids with high *** contrast,the inception voltage of streamers initiated at permittivity matched interfaces are shown to be highest of the *** streamer inception voltage is also studied for different distances be-tween the liquid/solid interface and the point electrode with a permittivity matched *** results show a dependency of the inception voltage and the distance be-tween the point electrode and the ***,an analysis of the observation is performed to show that the Townsend‐Meek criterion cannot predict the obtained results.

关键词： solid liquid electrode

Matched Asymptotic Expansions of the Eigenvalues of a 3-D Boundary-Value Problem Relative to Two Cavities Linked by a Hole of Small Size

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Communications in Computational Physics 2012年第2期11卷 456-471页

作者： abderrahmane Bendali M’Barek Fares Abdelkader Tizaoui Sebastien Tordeux Electromagnetism and Acoustics CERFACS42 Avenue Gaspard CoriolisF-31100 ToulouseFrance Toulouse University INSA-ToulouseMathematical Institute of ToulouseUMR-CNRS 5219135 avenue de RangueilF-31077 ToulouseFrance Laboratoire de Mathematiques et de leurs Applications UMR-CNRS 5142Universite de Pau et des Pays de l’AdourF-64013 PauFrance Project Team MAGIQUE-3D INRIA Bordeaux-Sud-OuestF-64013 PauFrance

In this article,we consider a domain consisting of two cavities linked by a hole of small *** derive a numerical method to compute an approximation of the eigenvalues of an elliptic operator without refining in the ne... 详细信息

关键词： Elliptic operator matched asymptotic expansions eigenvalue problem finite elements