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Robust SVM-direct torque control of induction motor based on sliding mode controller and sliding mode observer

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Frontiers in Energy 2020年第4期14卷 836-849页

作者： Abdelkarim AMMAR Amor BOUREK abdelhamid BENAKCHA LGEB Laboratory Department of Electrical EngineeringUniversity of BiskraBiskraBP 145Algeria

This paper proposes a design of control and estimation strategy for induction motor based on the variable structure *** describes a coupling of sliding mode direct torque control(DTC)with sliding mode flux and speed *** algorithm uses direct torque control basics and the sliding mode approach.A robust electromagnetic torque and flux controllers are designed to overcome the conventional SVM-DTC draw・backs and to ensure fast response and full reference tracking with desired dynamic behavior and low ripple *** sliding mode controller is used to generate reference voltages in stationary frame and give them to the controlled motor after modulation by a space vector modulation(SVM)*** second aim of this paper is to design a sliding mode speed/flux observer which can improve the control performances by using a sensorless algorithm to get an accurate estimation,and consequently,increase the reliability of the system and decrease the cost of using *** effectiveness of the whole composed control algorithm is investigated in different robustness tests with simulation using Matlab/Simulink and verified by real time experimental implementation based on dS pace 1104 board.

关键词： induction motor direct torque control(DTC) space vector modulation(SVM) sliding mode control(SMC) sliding mode observer(SMO) dS1104

Cauchy-Stieltjes Kernel Families and Free Multiplicative Convolution

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Communications in Mathematics and Statistics 2024年第4期12卷 679-694页

作者： Raouf Fakhfakh abdelhamid Hassairi College of Science and Arts in Gurayat Jouf UniversityGurayatSaudi Arabia Laboratory of Probability and Statistics Sfax UniversitySfaxTunisia

In this paper,we determine the effect of the free multiplicative convolution on the pseudo-variance function of a Cauchy-Stieltjes kernel *** then use the machinery of variance functions to establish some limit theorems related to this type of convolution and involving the free additive convolution and the Boolean additive convolution.

关键词： Variance function Cauchy kernel Free multiplicative convolution S-transform

Adsorption of dyes onto activated carbon prepared from olive stones

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Journal of Environmental Sciences 2005年第6期17卷 998-1003页

作者： Souad NAJAR-SOUISSI Abdelmottaleb OUEDERNI abdelhamid RATEL Chemical Reactors and Process Control National School of Engineers of Gabes Medenine Street 6029 Tunisia Chemical Reactors and Process Control National School of Engineers of Gabes Medenine Street 6029 Tunisia Chemical Reactors and Process Control National School of Engineers of Gabes Medenine Street 6029 Tunisia

Activated carbon was produced from olive stones（OSAC） by a physical process in two steps. The adsorption character of this activated carbon was tested on three colour dyes molecules in aqueous solution： Methylene blue（MB）, Rhodamine B（RB） and Congo Red（CR）. The adsorption equilibrium was studied through isotherms construction at 30℃, which were well described by Langmuir model. The adsorption capacity on the OSAC was estimated to be 303 mg/g, 217 mg/g and 167 mg/g respectively for MB, RB and CR. This activated carbon has a similar adsorption properties to that of commercial ones and show the same adsorption performances. The adsorption kinetics of the MB molecule in aqueous solution at different initial concentrations by OSAC was also studied. Kinetic experiments were well fitted by a simple intra-particle diffusion model. The measured kinetics constant was influenced by the initial concentration and we found the following correlation： Kid = 1.55 C0^0.51.

关键词： activated carbon olive stones adsorption dyes isotherms kinetic

A NEW HYBRIDIZED MIXED WEAK GALERKIN METHOD FOR SECOND-ORDER ELLIPTIC PROBLEMS

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Journal of Computational Mathematics 2022年第4期40卷 499-516页

作者： abdelhamid Zaghdani Sayed Sayari Miled EL Hajji University of Tunis Boulevard du 9 avril 1939 TunisDepartment of MathematicsEnsitTaha Hussein AvenueMontfleuryTunisTunisia Northern Border University Faculty of Arts and ScienceRafhaP.O.840Saudi Arabia Carthage University Isteub2 Rue de l’Artisanat Charguia 22035 TunisTunisia Department of Mathematics Faculty of SciencesUniversity of JeddahSaudi Arabia ENIT-LAMSINBP.371002 Tunis-Belv´ed`ereTunis El Manar UniversityTunisia

In this paper,a new hybridized mixed formulation of weak Galerkin method is studied for a second order elliptic *** method is designed by approximate some operators with discontinuous piecewise polynomials in a shape regular finite element *** discrete inequalities are presented on discontinuous spaces and optimal order error estimations are *** numerical results are reported to show super convergence and confirm the theory of the mixed weak Galerkin method.

关键词： Weak Galerkin Weak gradient Hybridized mixed finite element method Second order elliptic problems

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

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

A New Non-centrosymmetric Microporous Fluorinated Iron Phosphate： Structural Elucidation, Spectroscopic Study and Hirshfeld Surface Analysis

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Chemical Research in Chinese Universities 2016年第4期32卷 519-526页

作者： Nabaa BOUZIDIA Besma HAMDI abdelhamid BEN SALAH Laboratory of Materials Science and Environment Faculty of Sciences of Sfax University of Sfax PB 1171 3000 SFAX Tunisia

The crystal structure of a new non-centrosymmetric microporous fluorinated iron phosphate, （H30）2[Fe4（H2O）2F4（PO4）2（HPO4）2]（H2O）, was determined by single crystal X-ray diffraction analysis and the result reveals that it belongs to the orthorhombic system with four molecules in the unit cell（space group P212121）. Thus, the complex was characterized by powder X-ray diffraction, spectroscopic techniques（Fourier transform infrared and Fourier transform Raman） and 19F MAS NMR. The elemental analysis of the sample was also carried out. The chiral inorganic sheets, which stacked along [100] showed the presence of FeF2O4 as well as FeF2O3H2O octahedra, PO4 besides HPO4 tetrahedra, hydronium ions（H3O＋） and isolated water molecules. Hirshfeld surface analysis, especially dnom surface and fingerprint plots, were used for decoding the intermolecular interactions in the crystal network and the contribution of component units for the construction of the 3D architecture. From the Hirshfeld surfaces and 2D fingerprint analysis, it was found that the subtle interactions, such as H...H associating the third intense interaction of all intercontacts, provide extra stabilization in addition to the presence of the strong hydrogen bonds mentioned above.

关键词： Non-centrosymmetric structure Iron fluorinated phosphate Hirshfeld surface analysis

A review on the rheology of heavy crude oil for pipeline transportation

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Petroleum Research 2021年第2期6卷 116-136页

作者： Farid Souas abdelhamid Safri Abdelbaki Benmounah LEGHYD Laboratory Faculty of Civil EngineeringUniversity of Science and Technology Houari Boumediene(USTHB)Bab EzzouarAlgerAlgeria Research Unit Materials Processes and Environment(UR-MPE)Faculty of Engineering ScienceUniversity M’Hamed BougaraBoumerdesAlgeria

Given the combination of rising global energy demand and the decline in conventional crudes, heavycrudes are generally considered to be the future energy resource. In many regions of the world, heavycrude oil must be transported through pipelines from the point of production to storage facilities orrefineries. The transportation of heavy crude oil by pipeline poses serious problems related to the highviscosity and flow difficulties, particularly in cold climates or offshore conditions. Indeed, the viscosity ofcrude oil is an important physical property that influences and controls crude oil flow in *** introduces resistance to movement by causing a shear or frictional force between the fluidparticles and the boundary walls. This high viscosity means that the pumping power requirements forcrude oil in a long-distance pipeline are very high in order to overcome the increasing shear and frictionforces. Therefore, in order to facilitate the pumping of these viscous oils and reduce operating expensesand the negative impact of pressure drops in pipelines during flow and processing, their viscosity mustbe reduced. Various techniques are used to increase pumping efficiency and improve the flow of crude oilthrough the pipeline, which may present logistical, technical or economic disadvantages for a givenapplication. The main ones are the addition of surfactants or polymers, dilution with lighter crudes, useof water as annular fluid, thermal remediation and emulsification with surfactant (O/W). This reviewhighlights the methods currently used to enhance the fluidity of heavy crude oil in pipelines behindrheology improvement, in particular the addition of additives and the use of water and surfactants tocreate a stable emulsion of heavy crude oil in water have been considered.

关键词： Additives Emulsion Heavy crude oil Rheology Viscosity

Model variables identification of a gas turbine using a subspace approach based on input/output data measurements

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Control Theory and Technology 2021年第2期19卷 183-196页

作者： Hakim Bagua Ahmed Hafaifa abdelhamid Iratni Mouloud Guemana Applied Automation and Industrial Diagnostics Laboratory Faculty of Science and TechnologyUniversity of Djelfa17000DjelfaAlgeria Gas Turbine Joint Research Team University of Djelfa17000DjelfaAlgeria Faculty of Science and Technology University of Bordj Bou Arreridj34000Bordj Bou ArreridjAlgeria

This paper deals with a state model identification of a gas turbine used for gas transport, using a subspace approach of the state space model. This method provides a reliable and robust state representation of the model, taking advantage of its benefits in the control, monitoring, and supervision of this machine. The model for each variable is set so that the state matrices associated with the gas turbine model are determined from their real input/output data. The comparison of the obtained identification results with those of the actual turbine operation serves to validate the proposed model in this work. This numerical algorithm of the subspace identification method is full of information and more accurate in terms of residual modeling error, and expresses a very high level of confidence in the identified turbine system dynamics. Hence, the controllability and observability tests of turbine operation for different input/output variables allowed to validate the real-time operating stability of the turbine.

关键词： System identification Subspace identification State space model Gas turbine N4SID algorithm