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Optimized Two-Level Ensemble Model for Predicting the Parameters of Metamaterial Antenna

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Computers, Materials & Continua 2022年第10期73卷 917-933页

作者： abdelaziz A.Abdelhamid Sultan R.Alotaibi Department of Computer Science College of Computing and Information TechnologyShaqra UniversitySaudi Arabia Department of Computer Science College of Science and HumanitiesShaqra UniversitySaudi Arabia Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityEgypt

Employing machine learning techniques in predicting the parameters of metamaterial antennas has a significant impact on the reduction of the time needed to design an antenna with optimal parameters using simulation *** this paper,we propose a new approach for predicting the bandwidth of metamaterial antenna using a novel ensemble *** proposed ensemble model is composed of two levels of regression *** first level consists of three strong models namely,random forest,support vector regression,and light gradient boosting *** the second level is based on the ElasticNet regression model,which receives the prediction results from the models in the first level for refinement and producing the final optimal *** achieve the best performance of these regression models,the advanced squirrel search optimization algorithm(ASSOA)is utilized to search for the optimal set of hyper-parameters of each *** results show that the proposed two-level ensemble model could achieve a robust prediction of the bandwidth of metamaterial antenna when compared with the recently published ensemble models based on the same publicly available benchmark *** findings indicate that the proposed approach results in root mean square error(RMSE)of(0.013),mean absolute error(MAE)of(0.004),and mean bias error(MBE)of(0.0017).These results are superior to the other competing ensemble models and can predict the antenna bandwidth more accurately.

关键词： Ensemble model parameter prediction metamaterial antenna machine learning model optimization

COURSE TiMETABLiNG AT A TUNiSiAN UNiVERSiTY:A CASE STUDY

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Journal of Systems Science and Systems Engineering 2008年第3期17卷 334-352页

作者： abdelaziz DAMMAK Abdelkarim ELLOUMi Hichem KAMOUN Jacques A.FERLAND Department of Applied Quantitative Methods GIAD Laboratory University of SfaxFSEGTunisia Department of Applied Quantitative Methods GlAD Laboratory University of SfaxFSEGTunisia Département d'informatique et de Recherche Opérationnelle Universitéde Montréal QuébecCanada

This paper deals with the Course Timetabling Problem at an institution in a Tunisian University. We introduce a heuristic procedure to construct a feasible timetable for all lectures and tutorials taken by different groups of each sub-section of any section. We describe the timetabling problem using a list of all specific hard and soft constraints. We formulate the problem as a set of linear constraints using two sets of binary variables corresponding to lectures and tutorials, respectively. This heuristic is illustrated with real data for a sub-section of the Faculty of Economics and Management Sciences of Sfax in Tunisia, and the resulting timetables are compared with those generated manually. The results of another full section have confirmed the good quality of the proposed heuristic when compared with the hand made solution.

关键词： Educational timetabling integer programming implementations heuristic search

Fuzzy Genetic Sharing for Dynamic Optimization

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international Journal of Automation and computing 2012年第6期9卷 616-626页

作者： Khalid Jebari abdelaziz Bouroumi Aziz Ettouhami Conception and Systems Laboratory Faculty of SciencesMohammed V-Agdal University Modeling and instrumentation Laboratory Ben Msik Faculty of SciencesHassan II Mohammedia-Casablanca University

Recently,genetic algorithms(GAs) have been applied to multi-modal dynamic optimization(MDO).in this kind of optimization,an algorithm is required not only to find the multiple optimal solutions but also to locate a dynamically changing *** fuzzy genetic sharing(FGS) approach is based on a novel genetic algorithm with dynamic niche sharing(GADNS).FGS finds the optimal solutions,while maintaining the diversity of the *** this,FGS uses several ***,an unsupervised fuzzy clustering method is used to track multiple optima and perform ***,a modified tournament selection is used to control selection ***,a novel mutation with an adaptive mutation rate is used to locate unexplored search *** effectiveness of FGS in dynamic environments is demonstrated using the generalized dynamic benchmark generator(GDBG).

关键词： Genetic algorithms unsupervised learning fuzzy clustering dynamic optimization evolutionary algorithms dynamic niche sharing Hill s diversity index multi-modal function optimization.

Robust Prediction of the Bandwidth of Metamaterial Antenna Using Deep Learning

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Computers, Materials & Continua 2022年第8期72卷 2305-2321页

作者： abdelaziz A.Abdelhamid Sultan R.Alotaibi Department of Computer Science College of Computing and Information TechnologyShaqra UniversityShaqraSaudi Arabia Department of Computer Science College of Science and Human StudiesShaqra UniversitySaudi Arabia Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityEgypt

The design ofmicrostrip antennas is a complex and time-consuming process,especially the step of searching for the best design ***,the performance ofmicrostrip antennas can be improved usingmetamaterial,which results in a new class of antennas called metamaterial *** parameters affect the radiation loss and quality factor of this class of antennas,such as the antenna ***,the optimal values of the design parameters of metamaterial antennas can be predicted using machine learning,which presents a better alternative to simulation tools and trialand-error ***,the prediction accuracy depends heavily on the quality of the machine learning *** this paper,and benefiting from the current advances in deep learning,we propose a deep network architecture to predict the bandwidth of metamaterial *** results show that the proposed deep network could accurately predict the optimal values of the antenna bandwidth with a tiny value of mean-square error(MSE).in addition,the proposed model is comparedwith current competing approaches that are based on support vector machines,multi-layer perceptron,K-nearest neighbors,and ensemble *** results show that the proposed model is better than the other approaches and can predict antenna bandwidth more accurately.

关键词： Metamaterial antenna deep learning bandwidth prediction regression models

Theoretical investigation of the pressure broadening D1 and D2 lines of cesium atoms colliding with ground-state helium atoms

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Chinese Physics B 2019年第10期28卷 300-308页

作者： Moussaoui abdelaziz Alioua Kamel Allouche Abdul-rahman Bouledroua Moncef Universite Cherif Messaidia B.P.1553Souk-Ahras 41000Algerie Laboratoire de Physique de la Matiere et du Rayonnement LPMR Universite Cherif MessaidiaB.P.1553Souk-Ahras 41000Algerie Universite Lyon 1 CNRSLASIM UMR5579bat.A.Kastler43 Bd du 11 novembre 1918F-69622 VilleurbanneFrance Laboratoire de Physique des Rayonnements LPR Universite Badji MokhtarB.P.12Annaba 23000Algerie

Full quantum mechanical calculations are performed to determine the broadening in the far wings of the cesium D1 and D2 line shapes arising from elastic collisions of Cs atom with inert helium atoms. The potential energy curves of the low-lying CsHe molecular states, as well as the related transition dipole moments, are carefully computed from ab initio methods based on state-averaged complete active space self-consistent field-multireference configuration interaction(SACASSCF-MRCi) calculations, involving the spin-orbit effect, and taking into account the Davidson and BSSE *** absorption and emission reduced coefficients are determined in the temperature and wavelength ranges of 323-3000 K and 800-1000 nm, respectively. Both profiles of the absorption and the emission are dominated by the free-free transitions,and exhibit a satellite peak in the blue wing near the wavelength 825 nm, attributed to B^2Σ1/2^+→ X^2Σ1/2^+/transitions. The results are in good agreement with previous experimental and theoretical works.

关键词： absorption coefficient emission coefficient pressure broadening potential curves

Adaptive Type-2 Fuzzy Sliding Mode Controller for SiSO Nonlinear Systems Subject to Actuator Faults

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international Journal of Automation and computing 2013年第4期10卷 335-342页

作者： Meriem Benbrahim Najib Essounbouli abdelaziz Hamzaoui Ammar Betta Research Center on Science and Technology of information and Communication University of Reims Champagne Ardenne University institute of Technology of Troyes Troyes F10026 France University of Hadj Lakhdar Batna Boukhlouf Med Elhadi StreetBatna 05000 Algeria

in this paper, an adaptive type-2 fuzzy sliding mode control to tolerate actuator faults of unknown nonlinear systems with external disturbances is presented. Based on a redundant actuation structure, a novel type-2 adaptive fuzzy fault tolerant control scheme is proposed using sliding mode control. Two adaptive type-2 fuzzy logic systems are used to approximate the unknown functions, whose adaptation laws are deduced from the stability analysis. The proposed approach allows to ensure good tracking performance despite the presence of actuator failures and external disturbances, as illustrated through a simulation example.

关键词： Type-2 fuzzy systems fault tolerant control sliding mode control adaptive system actuator faults.

Fixed Point Theorems for(p, q)-Quasi-Contraction Mappings in Cone Metric Spaces

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Chinese Annals of Mathematics,Series B 2016年第2期37卷 211-220页

作者： Wajdi CHAKER abdelaziz GHRiBi Aref JERiBi Bilel KRiCHEN Higher institute of Applied Biology Medenine El Jorf Road Km 22MedenineTunisia Higher institute of Business Administration of Sfax Airport Road Km 4 B.P.N1013 3018 B.P.1013SfaxTunisia Department of Mathematics Faculty of Science of SfaxSoukra Road Km 3.5B.P.11713000SfaxTunisia Department of Mathematics Preparatory Engineering InstituteMenzel Chaker Road Km 0.5B.P.1172-3018SfaxTunisia

in this work, the authors introduce the concept of(p, q)-quasi-contraction mapping in a cone metric space. We prove the existence and uniqueness of a fixed point for a(p, q)-quasi-contraction mapping in a complete cone metric space. The results of this paper generalize and unify further fixed point theorems for quasi-contraction, convex contraction mappings and two-sided convex contraction of order 2.

关键词： Fixed points (p q)-Quasi-contractions Cone metric space

Accurate surface potential determination in Schottky diodes by the use of a correlated current and capacitance voltage *** to n-inP

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Journal of Semiconductors 2011年第10期32卷 39-43页

作者： Ali Ahaitouf abdelaziz Ahaitouf Jean Paul Salvestrini Hussein Srour Laboratoire Signaux Systemes et Composants DGE Faculty of Sciences and TechnologyUniversite Sidi Mohammed Ben AbdellahP.O.Box 2202FES Morocco LiMAO Faculte polydisciplinaire de Taza Universite Sidi Mohammed Ben Abdellah de FesBP 1223 Taza-GareMorocco Laboratoire Materiaux Optiques Photonique et SystemesEA 4423Universite Paul Verlaine-MetzSupelec2 rue E.Belin57070 MetzFrance

Based on current voltage（i-Vg） and capacitance voltage（C-Vg） measurements,a reliable procedure is proposed to determine the effective surface potential Vd（Vg） in Schottky *** the framework of thermionic emission,our analysis includes both the effect of the series resistance and the ideality factor,even voltage dependent. This technique is applied to n-type indium phosphide（n-inP） Schottky diodes with and without an interfacial layer and allows us to provide an interpretation of the observed peak on the C-Vg *** study clearly shows that the depletion width and the flat band barrier height deduced from C-Vg,which are important parameters directly related to the surface potential in the semiconductor,should be estimated within our approach to obtain more reliable information.

关键词： Schottky diode interface states surface potential ideality factor barrier height capacitance voltage current measurements

Symbiotic Bacteria Diversity and the Fitness of the Oriental Latrine Fly Chrysomya Megacephala (Diptera: Calliphoridae)

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Symbiotic Bacteria Diversity and the Fitness of the Oriental...

作者： abdelaziz MAHMOUD abdelaziz MANSOUR 华中农业大学

学位级别：硕士

昆虫体内共生菌可通过多种方式对寄主生物学及生理学产生影响,根据共生菌在昆虫体内存在的部位可将其分为内共生菌与外共生菌,它们以共生、寄生或病原菌的形式与寄主建立联系。大头金蝇Chrysoma megacephala(双翅目:丽蝇科)是一种全球... 详细信息

昆虫体内共生菌可通过多种方式对寄主生物学及生理学产生影响,根据共生菌在昆虫体内存在的部位可将其分为内共生菌与外共生菌,它们以共生、寄生或病原菌的形式与寄主建立联系。大头金蝇Chrysoma megacephala(双翅目:丽蝇科)是一种全球范围内分布的昆虫,也是法医昆虫学中最常见的丽蝇科昆虫之一。近年来,大头金蝇幼虫被广泛应用于作物秸秆和有机废弃物的转化,其成虫可对植物进行授粉,作为授粉昆虫。为满足自身卵子发生及幼虫生长发育的营养需求,大头金蝇需在脊椎动物伤口、尸体、花瓣及粪便上取食,在这种复杂的取食环境中,其体内共生菌发挥着重要作用。大头金蝇肠道共生物种类丰富,对于维持寄主适合度必不可少,然而,其肠道共生物的多样性以及共生物对宿主代谢和繁殖的影响尚不清楚。在本研究中,我们利用16S rRNA高通量测序技术(illumina MiSeq technology)对大头金蝇不同发育阶段相关细菌的菌群组成及多样性进行了分析;对大头金蝇幼虫肠道共生物进行了分离鉴定,筛选到几株纤维素降解菌,评估了纤维素酶活;将分离的共生菌添加到大头金蝇饲料中,研究其对寄主适合度的影响。主要结果如下:1.利用高通量测序技术研究大头金蝇肠道细菌多样性利用高通量测序技术(MiSeq technique),对大头金蝇雌成虫、卵、发育6h的初孵幼虫、发育72h的幼虫、鸡肉(大头金蝇产卵基质)共生菌菌群结构及组成进行分析。测序共获得423个OTU,其中51个OUT在各样品中均存在,测序结果共注释了 15个门,28个纲,74个目,138个科,260个属的细菌类群。其中,变形菌门、厚壁菌门、放线菌门及拟杆菌门细菌在各样品中均存在。沃尔巴克氏体Wolbachia、漫游球菌Vagococcus、葡萄球菌Staphlyococcus是样品中优势菌群,这些共生菌可能对大头金蝇卵子发生及幼虫的发育具有重要作用。2.大头金蝇肠道共生菌的分离与鉴定采用连续稀释平板计数法对大头金蝇肠道可培养共生菌进行分离,并对分离的细菌进行16s rRNA基因测序,结合NCBi-Blast工具对其进行鉴定。结果显示,大头金蝇幼虫肠道菌群多样性丰富,变形菌门、拟杆菌门和厚壁菌门细菌是大头金蝇不同发育阶段的优势菌群,变形菌门细菌在各发育阶段中含量最多。变形杆菌属细菌是一龄幼虫及三龄幼虫肠道优势菌,占比分别高达25%、30%,假单胞菌是二龄幼虫肠道优势菌(21%)。共生菌对幼虫发育及寄主生物学具有重要作用,后续对分离到的8种共生菌进行深入研究,以期利用益生菌促进大头金蝇的大量饲养。3.大头金蝇肠道内纤维素降解菌的分离及功能验证为了研究在富含纤维素的麦麸饲料中肠道细菌对幼虫存活率的影响,我们利用羧甲基纤维素钠(CMC)培养基从大头金蝇幼虫体内分离纤维素降解菌。基于细菌形态学分析及16S rRNA分子鉴定,分离到10株细菌,分别属于假单胞菌属Pseudomonas、不动杆菌属Acinetobacter、无色杆菌属Achrcmobacter和产碱菌属Alcaligenes细菌。通过测量菌落及纤维素降解圈直径对分离到的细菌纤维素降解能力进行评估。结果表明:(1)荧光假单胞菌Pseudomonas fluorescens及浅黄色假单胞菌Pseudomonas lurida在CMC培养基上长势最好,菌落直径均大于8mm;(2)对不同细菌的纤维素降解圈大小进行比较,其中浅黄色假单胞菌、解蛋白不动杆菌Acinetobacter proteolyticus、猴假单胞菌Pseudomonas simiae所产生的纤维素降解圈直径依次为19.97 mm、6.97 mm、5.88 mm,浅黄色假单胞菌的降解圈与菌落直径比值(D/d)最大(2.46);(3)猴假单胞菌纤维素酶活最高。浅黄色假单胞菌、解蛋白不动杆菌及猴假单胞菌可能具备纤维素降解能力,提高幼虫在富含纤维素培养基上的存活率。4.大头金蝇肠道益生菌对寄主适合度的影响对上述自大头金蝇肠道内分离得到的8种细菌进行富集培养,待其吸光度值(OD600)为0.5时进行饲料添加试验。试验设置三组处理:共生菌组(正常幼虫饲喂含菌饲料)、无菌组(抗生素处理后的幼虫饲喂含菌饲料)及对照组(正常幼虫饲喂常规饲料),饲喂5天后幼虫均已化蛹,随后将蛹转移至无菌沙子内待其羽化。试验记录大头金蝇不同发育阶段发育历期、幼虫存活率及蛹重。结果显示:(1)各处理组的幼虫发育历期无显著差异;(2)与无菌组及对照组相比,共生菌可促进幼虫发育,提高幼虫存活率;共生菌组幼虫存活率为73%,蛹羽化率为91%;无菌组分别为60%,83%,而对照组为70%,76%;(3)蛹的干重数据与幼虫存活率趋势相似。上述研究为益生菌在大头金蝇大规模饲养技术中的应用奠定了基础。总之,本文通过高通量测序表明沃尔巴克氏体、漫游球菌和葡萄

关键词：大头金蝇共生菌纤维素分解细菌 Wolbachia MiSeq