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Positron Affinity, Deformation Potential and Diffusion Constant in AlxIn1-xSb Ternary Semiconductor Alloys

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Acta Metallurgica Sinica(English Letters) 2016年第7期29卷 661-667页

作者： Nour EI-houda Fares Nadir Bouarissa Materials and Electronic Systems Laboratory University of Bordj-Bou-Arr6ridj 34000 Bordj-Bou-Arr6ridj Algeria Laboratory of Materials Physics and Its Applications University of M'sila 28000 M'sila Algeria 9 Rue K Fg des martyrs 34000 Bordj-Bou-Arreridj Algeria

The present investigation deals with the positron behaviour in Alxlnl_xSb ternary semiconductor alloys in the zinc-blende phase. The calculations are mainly based on a pseudopotential approach coupled with the independent particle model. Features such as elastic constants, electron and positron chemical potentials, positron deformation potential and positron diffusion constant are determined. Moreover, the positron affinity to InSb, A1Sb and their related ternary alloys and heterostructures is calculated. The present results are compared to experiment and found to be in reasonably good agreement. The information gathered from the present study can help in understanding the positron trapping at interfaces and precipitates and might be useful in slow-positron-beam experiments.

关键词： Semiconductor alloys Positrons Diffusion Surface and interface states Heterostructures

Analysis of the Influence of Viscosity and Thermal Conductivity on Heat Transfer by Al2O3-Water Nanofluid

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Fluid Dynamics & Materials Processing 2020年第2期16卷 181-198页

作者： houda Jalali Hassan Abbassi Unit of Computational Fluid Dynamics and Transfer Phenomena National Engineering School of Sfax(ENIS)University of SfaxSfaxTunisia

The addition of nanoparticles into liquid,even at low concentrations,leads to an increase in both,dynamic viscosity and thermal ***,the increase in temperature causes an increase in thermal conductivity and a decrease in the nanofluid *** this context,a numerical investigation of the competition between viscosity and thermal conductivity about their effects on heat transfer by Al_(2)O_(3)-water nanofluid was conducted.A numerical study of heat transfer in a square cavity,filled with Al_(2)O_(3)-water nanofluid and heated from the left side,was presented in this ***,momentum,and thermal energy equations are solved by the finite volume *** the pressure-velocity coupling,the SIMPLER algorithm was *** working conditions,allowing the increase of heat transfer,are *** addition,two correlations for viscosity and thermal conductivity of Al_(2)O_(3)-water nanofluid as functions of the concentration and diameter size based on experimental measurement are *** correlations were more precisely compared to those given by the theoretical ***,other models for viscosity and conductivity depending on temperature are used and *** results reveal that heat transfer by Al_(2)O_(3)-water nanofluid is enhanced only when the temperature exceeds 40℃ and the diameter size does not exceed a certain limit of the order of 45-50 nm depending on temperature.

关键词： Heat transfer nanofluid viscosity thermal conductivity

Analysis of the Influence of Viscosity and Thermal Conductivity on Heat Transfer By Al_(2)O_(3)-Water Nanofluid

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Fluid Dynamics & Materials Processing 2019年第3期15卷 253-270页

作者： houda Jalali Hassan Abbassi Unit of Computational Fluid Dynamics and Transfer Phenomena National Engineering School of Sfax(ENIS)University of SfaxSfaxTunisia

关键词： Heat transfer nanofluid viscosity thermal conductivity

Relative(n,k)-Weak Cotorsion Modules

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Algebra Colloquium 2024年第3期31卷 481-498页

作者： Mostafa Amini houda Amzil Driss Bennis Department of Mathematics Faculty of SciencesPayame Noor UniversityTehranIran Department of Mathematics Faculty of Sciences EI Jadida Chouaib Doukkali UniversityMorocco Department of Mathematics Faculty of Sciences Mohammed V University in RabatMorocco

Let R be a ring and n,k be two non-negative *** an extension of several known notions,we introduce and study(n,k)-weak cotorsion modules using the class of right R-modules with n-weak fat dimensions at most *** exampl... 详细信息

关键词： (n,k)-weak cotorsion module n-weak injective module n-weak fat module n-super finitely presented module

Second Order Sliding Mode Control for Discrete Decouplable Multivariable Systems via Input-output Models

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International Journal of Automation and computing 2015年第6期12卷 630-638页

作者： houda Romdhane Khadija Dehri Ahmed Said Nouri Numerical Control of Industrial Processes National Engineering School of Gabes University of Gabes

The problem of the chattering phenomenon is still the main drawback of the classical sliding mode control. To resolve this problem, a discrete second order sliding mode control via input-output model is proposed in this paper. The proposed control law is synthesized for decouplable multivariable systems. A robustness analysis of the proposed discrete second order sliding mode control is carried out. Simulation results are presented to illustrate the effectiveness of the proposed strategy.

关键词： Discrete second order sliding mode control decoupl

Enhancing power generation via an adaptive neuro-fuzzy and backstepping maximum-power-point tracking approach for photovoltaic single-ended primary inductor converter system

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Clean Energy 2024年第5期8卷 34-44页

作者： Khalil Chnini houda Jouini Hatem Allagui Abdelkader Mami Laboratory of Energy Applications and Renewable Energy Efficiency(LAPER) Faculty of Sciences of TunisEl Manar UniversityTunis 1068Tunisia

The distinct characteristics of photovoltaic generators related to power and current present a complex problem in terms of opti-mizing their power *** tackle this,maximum-power-point tracking techniques such as the adaptive neuro-fuzzy inference system are frequently utilized for their swift adaptability and reduced *** addition,the backstepping controller is often selected to handle both linear and non-linear systems due to its exceptional *** purpose of this research is to propose an innovative method that merges the adaptive neuro-fuzzy inference system and backstepping controller to refine the tracking of the optimal power point and to bolster the stability of the photovoltaic system in the face of unpredictable scenarios,such as those pre-sented by the Ropp irradiance examination,which utilizes a single-ended primary inductor converter as a stage for power electronics *** conducted using MATLAB®/Simulink®demonstrate that the combination of adaptive neuro-fuzzy inference system and backstepping controller achieves an impressive efficiency of 99.6%and exhibits fast,robust,and accurate responses com-pared with other algorithms such as artificial neural networks combined with the backstepping controller and conventional perturb and observe algorithm.

关键词： MPPT ANFIS backstepping stand-alone PV system SEPIC stability

Dynamic characteristics and improved MPPT control of PV generator

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Frontiers in Energy 2013年第3期7卷 342-350页

作者： houda BRAHMI Rachid DHIFAOUI Higher Institute of Medicals Technologies (ISTMT) 9 Rue ZouhairEssafi 1006 Tunis Tunisia National Institute of Applied Sciences and Technology (INSAT) Centre Urbain Nord BP 6761080 Tunis Cedex Tunisia

This paper presents a mathematical model of photovoltaic （PV） module and gives a strategy to calculate online the maximum power point （MPP）. The variation of series and shunt resistor are taken into account in the model and are dynamically identified using the Newton-Raphson algorithm. The effectiveness of the proposed model is verified by laboratory experiments obtained by implementing the model on the dSPACE DS1104 board.

关键词： modeling of photovoltaic (PV) generator maximum power point tracking (MPPT) estimation para meters real time controller

A New Sliding Function for Discrete Predictive Sliding Mode Control of Time Delay Systems

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International Journal of Automation and computing 2013年第4期10卷 288-295页

作者： Abdennebi Nizar Ben Mansour houda Nouri Ahmed Said Numerical Control of Industrial Processes National Engineering School of Gabes University of Gabes

The control of time delay systems is still an open area for research. This paper proposes an enhanced model predictive discrete-time sliding mode control with a new sliding function for a linear system with state delay. Firstly, a new sliding function including a present value and a past value of the state, called dynamic surface, is designed by means of linear matrix inequalities （LMIs）. Then, using this dynamic function and the rolling optimization method in the predictive control strategy, a discrete predictive sliding mode controller is synthesized. This new strategy is proposed to eliminate the undesirable effect of the delay term in the closed loop system. Also, the designed control strategy is more robust, and has a chattering reduction property and a faster convergence of the system s state. Finally, a numerical example is given to illustrate the effectiveness of the proposed control.

关键词： State time delay systems discrete sliding mode control model predictive control dynamic sliding function linear matrix inequalities (LMIs) chattering.

Antioxidant Machinery Related to Decreased MDA Generation by Thymus Algeriensis Essential Oil-induced Liver and Kidney Regeneration

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Biomedical and Environmental Sciences 2016年第9期29卷 639-649页

作者： Guesmi Fatma Amit K Tyagi Bellamine houda Landoulsi Ahmed Laboratory of Biochemistry and Molecular Biology Faculty of Sciences of Bizerte University of Carthage 1054 Tunisia Department of Experimental Therapeutics The University of Texas M. D. Anderson Cancer Center 1515 Holcombe Boulevard Houston TX 77030 USA Service of Anatomo-Pathology of Menzel Bourguiba Bizerte 1054 Tunisia

Objective This study was conducted to determine the histopathological and biochemical effects of Thymus algeriensis essential oil （TEO） on hydrogen peroxide （H2O2）-induced oxidative stress in liver and kidney tissues of rats. Methods Rats were treated in six groups and were exposed for 2 weeks to low （LD; 100 μmol/L） and high doses （HD; 1 mmol/L） of H2O2 in the presence or absence of TEO （180 mg/kg）. Liver and kidney atrophy was measured by using biochemical and histopathological assays. Results Our study demonstrated that H2O2 induced liver and kidney atrophy, as evidenced by the significant elevation of serum aminotransferase, urea, and creatinine levels compared with those in the control rats. Urea levels were estimated by evaluating the activity of serum urease that hydrolyzes urea into CO2 and ammonia. However, TEO treatment significantly alleviated oxidative stress in the H2O2-induced liver and kidney toxicity model by reducing the levels of malondialdehyde concomitantly with marked elevations in superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase, as well as decrease in glutathione activity. Conclusion Our data demonstrated that TEO protected against H202 toxicity by decreasing oxidant levels and DNA damage, as well as increasing antioxidant levels, indicating that TEO has a spectrum of antioxidant and DNA-protective properties.

关键词： Liver and kidney atrophy Hydrogen peroxide Thymus algeriensis Antioxidants Toxicity