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Geodesic equation in non-commutative gauge theory of gravity

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Chinese Physics C 2022年第10期46卷 193-206页

作者： Abdellah touati Slimane Zaim Laboratoire de Physique des Rayonnements et de leurs Interactions avec la Matiere Departement de Physique Faculte des Sciences de la Matiere Universite de Batna-1Batna 05000Algeria Departement de Physique Faculte des Sciences de la Matière Universitéde Batna-1Batna 05000Algeria

In this study,we construct a non-commtative gauge theory of the modified structure of the gravitational field using the Seiberg-Witten map and the general tetrad fields of Schwarzschild space-time to show that the noncommutative geometry removes the singularity at the origin of the black hole,thus obtaining a non-singular Schwarzschild black *** geodetic structure of this black hole presents new types of motion next to the event horizon within stable orbits that are not allowed by the ordinary Schwarzschild *** noncommutative periastron advance of the Mercury orbit is obtained,and with the available experimental data,we find a parameter of non-commutativity on the order of 10^(-25)s·kg^(-1).This result shows that the new fundamental length,√h■,is on the order of 10^(-31)m.

关键词： non-commutative geometry gauge gravity Schwarzschild space-time geodesic equation

A sliding-neural network control of induction-motor-pump supplied by photovoltaic generator

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Protection and Control of Modern Power Systems 2019年第1期4卷 332-348页

作者： Hichem Hamdi Chiheb Ben Regaya abderrahmen Zaafouri University of Tunis Higher National Engineering School Of Tunis(ENSIT)Engineering Laboratory of Industrial Systems and Renewable Energies(LISIER)5 avenue Taha HusseinPO Box 561008TunisTunisia

Energy production from renewable sources offers an efficient alternative non-polluting and sustainable solution. Among renewable energies, solar energy represents the most important source, the most efficient and the least expensive compared to other renewable sources. Electric power generation systems from the sun’s energy typically characterized by their low efficiency. However, it is known that photovoltaic pumping systems are the most economical solution especially in rural areas. This work deals with the modeling and the vector control of a solar photovoltaic (PV) pumping system. The main objective of this study is to improve optimization techniques that maximize the overall efficiency of the pumping system. In order to optimize their energy efficiency whatever, the weather conditions, we inserted between the inverter and the photovoltaic generator (GPV) a maximum power point adapter known as Maximum Power Point Tracking (MPPT). Among the various MPPT techniques presented in the literature, we adopted the adaptive neuro-fuzzy controller (ANFIS). In addition, the performance of the sliding vector control associated with the neural network was developed and evaluated. Finally, simulation work under Matlab / Simulink was achieved to examine the performance of a photovoltaic conversion chain intended for pumping and to verify the effectiveness of the speed control under various instructions applied to the system. According to the study, we have done on the improvement of sliding mode control with neural network. Note that the sliding-neuron control provides better results compared to other techniques in terms of improved chattering phenomenon and less deviation from its reference.

关键词： Maximum power point tracking(MPPT) Adaptive Neuro-fuzzy inference systems(ANFIS) Photovoltaic(PV)systems Fuzzy logic controller(FLC) Pump Sliding mode controller

Mg(OH)_2 Nanorods Synthesized by A Facile Hydrothermal Method in the Presence of CTAB

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Nano-Micro Letters 2011年第3期3卷 153-159页

作者： Hassouna Dhaouadi Hedia Chaabane Fathi touati "Laboratoire des Matriaux Utiles" Institut National de Recherche et d’Analyse Physico-chimique Ple technologique de Sidi-Thabet "Laboratoire de Microbiologie" Institut National de Recherche et d’Analyse Physico-chimique Ple technologique de Sidi-Thabet

Magnesium hydroxide(Mg(OH)_2) nanorods were synthesized by a simple and facile hydrothermal method in the presence of cetyltetramethylammonium bromide(CTAB) as a surfactant. Nanorods of magnesium oxide Mg O were also induced by thermal decomposition of Mg(OH)_2 nanorods at 700. By using disk diffusion technique, the Mg(OH)_2 nanorods were found to exhibit higher antibacterial efficiency against several tested bacterial strains.

关键词： Nanorods Morphology Hydrothermal synthesis

Flexible impedance and capacitive tensile load sensor based on CNT composite

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Chinese Physics B 2016年第2期25卷 568-572页

作者： Zubair Ahmad Kh S Karimov Farid touati Department of Electrical Engineering College of Engineering Qatar University Doha 2713 Qatar Ghulam Ishaq Khan Institute of Engineering Sciences and Technology Topi District Swabi KPK 23640 Pakistan Center for Innovative Development of Science and New Technologies Academy of Sciences Aini St. 299/2 Dushanbe 734063 Tajikistan

In this paper, the fabrication and investigation of flexible impedance and capacitive tensile load sensors based on carbon nanotube（CNT） composite are reported. On thin rubber substrates, CNTs are deposited from suspension in water and pressed at elevated temperature. It is found that the fabricated load cells are highly sensitive to the applied mechanical force with good repeatability. The increase in impedance of the cells is observed to be 2.0 times while the decrease in the capacitance is found to be 2.1 times as applied force increases up to 0.3 N. The average impedance and capacitive sensitivity of the cell are equal to 3.4 N^（-1） and 1.8 N^（-1）, respectively. Experimental results are compared with the simulated values,and they show that they are in reasonable agreement with each other.

关键词： carbon nanotubes flexible tensile load impedance capacitive

Satisfactory Model Predictive Control for a Hybrid Single-phase Seven-level Converter

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CSEE Journal of Power and Energy Systems 2021年第5期7卷 1102-1112页

作者： Mohamed Tamim touati Shaoyuan Li Jing Wu Muhammad Ali Muhammad Mansoor Khan Department of Automation SEIEEShanghai Jiao Tong UniversityShanghai 200240China Department of Electrical Engineering.SEIEE Shanghai Jiao Tong UniversityShanghai 200240China.

Today,many hybrid multilevel converters with flying capacitors are being *** the practicality of these converters in reducing the switching devices count and the cost,it is challenging to balance their capacitor voltage *** unbalanced capacitors restrain the converters’performance and lead to failure in delivering the required *** paper proposes a model predictive control(MPC)for a seven-level converter based on an active neutral point clamped converter cascaded with an H-bridge.A conventional MPC uses a single cost function with two terms,one for current tracking and the other for capacitor balancing,which needs an accurate weighting factor to balance *** this work,the suggested MPC adopts a satisfactory optimization *** evaluates the capacitor charge membership to a nominal voltage range to define the degree of freedom in which to optimize the current tracking *** transforms the relationship between the two cost terms into a more collaborative *** proposed MPC improves the output current quality and balances the capacitor charge with the least number of *** and simulation results have validated the controller^effectiveness.

关键词： Hybrid converter model predictive control multilevel converter satisfactory optimization

Study of a ternary blend system for bulk heterojunction thin film solar cells

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Chinese Physics B 2016年第8期25卷 94-97页

作者： Zubair Ahmad Farid touati Shakoor R A Al-Thani N J Department of Electrical Engineering College of Engineering Qatar University Center for Advanced Materials Qatar University

In this research, we report a bulk heterojunction（BHJ） solar cell consisting of a ternary blend system. Poly（3-hexylthiophene） P3 HT is used as a donor and [6,6]-phenyl C61-butyric acid methylester（PCBM） plays the role of acceptor whereas vanadyl 2,9,16,23-tetraphenoxy-29 H, 31H-phthalocyanine（VOPc Ph O） is selected as an ambipolar transport material. The materials are selected and assembled in such a fashion that the generated charge carriers could efficiently be transported rightwards within the blend. The organic BHJ solar cells consist of ITO/PEDOT：PSS/ternary BHJ blend/Al structure. The power conversion efficiencies of the ITO/ PEDOT：PSS/P3HT：PCBM/Al and ITO/PEDOT：PSS/P3HT：PCBM：VOPcPhO/Al solar cells are found to be 2.3% and 3.4%, respectively.

关键词： organic semiconductor charge transport bulk heterojunction ternary blend

Spatio-temporal dynamics of cyanobacterial abundance and toxicity in a Mediterranean hypereutrophic lake

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Journal of Oceanology and Limnology 2023年第5期41卷 1834-1848页

作者： Salah ARIF Nawel DJEBBARI Saber BELHAOUES Hassen touati Mourad BENSOUILAH Eco-biology Laboratory for Marine Environments and Coastal Areas Faculty of SciencesMarine Sciences DepartmentUniversity of Badji MokhtarAnnaba 23000Algeria

The Mediterranean basin is considered one of the most vulnerable areas in the world under the impacts of global warming and changes in precipitation ***,a shallow and polymictic freshwater lake located in northeastern Algeria(36°50′N,08°23′E),has recently experienced a significant proliferation of harmful cyanobacteria resulting in the generation of *** carried out this study in order to understand the succession patterns of dominant cyanobacteria and cyanotoxin production and the factors driving this in Oubeira Lake.A total of 26 cyanobacterial genera were identified,and among them Microcystis and Planktothrix accounted for more than 60%of the overall cell *** summer/fall period was dominated by Microcystis,Planktothrix,and in lesser extend by Cylindrospermum,*** the fall/winter transition,Dolichospermum,Pseudanabaena,and Aphanizomenon were the dominant ***,the bloom-forming cyanobacteria showed significant differences between months but not between *** microcystins(MC-LR)was detected in all collected samples(0.62-and 19.14-μg MC-LR equivalent/L),but appeared in high concentrations throughout the period of dominance of Microcystis and *** was more sensitive to nutrients than to *** was more dependent on temperature than on nutrients,which explains their coexistence during summer-fall ***,both genera are positively correlated with MC-LR and would probably be the main producers of ***,Dolichospermum,and Aphanizomenon co-occurred at the end of Planktothrix dominance period(December).Aphanizomenon and Pseudanabaena were correlated negatively with temperature and positively with water *** showed a strong positive correlation with *** Lake,could serve as a model of how cyanobacteria blooms may develop in lakes within Mediterranean climates.

关键词： Oubeira Lake cyanobacteria microcystin spatiotemporal variations shallow hypereutrophic lake

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

Determinants of quinolone resistance in Escherichia coli causing community-acquired urinary tract infection in Bejaia,Algeria

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Asian Pacific Journal of Tropical Medicine 2014年第6期7卷 462-467页

作者： Yanat Betitra Vinuesa Teresa Vinas Miguel touati Abdelaziz Laboratoire d'ecologie Microbiologie.Universite A/Mira de Bejaia Laboratory of Molecular Microbiology and Antibiotics Dept.Pathology and Experimental therapeutics.Medical SchoolUniversity of Barcelona

Objective:To investigate the mechanisms of quinolone resistance and the association with other resistance markers among Esherichia coli(***) strains isolated from outpatient with urinary tract infection in north of ***:A total of 30 nalidixic acid-resistant *** isolates from outpatient with urinary tract infections from January 2010 to April 2011 in north of Algeria(Bejaia) were *** susceptibility was determined by disc diffusion assay,minimal inhibitory concentrations(MIC) of quinolone were determined by *** in the Quinolone Resistance-Determining Region(QRDR) of gyra and parC genes and screening for qnr(A,B and S) and bla genes were done by PCK and UNA ***:Most of the *** isolates(56.66%) were shown to carry mutations in gyrA and parC,igyra:Ser83Leu + Asp87Asn and parC:***.16.66 had only an alteration in gyrA:*** isolate produced qnrB-like and two *** isolates were CTXM-15 producers associated with TEM-1 producing in one ***-expression of bla_(LTV,M)_(15) and qnrB was determined in one *** ***:Our findings suggested the community emergence of gyrA and parC alterations and Qnr determinants that contributed to the development and spread of fluoroquinolone resistance in Algerian *** isolates.

关键词： Escherichia coli Community-acquired urinary tract infection QRDR Qnr ESBL