Publications Scientifiques
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Item An Analytical Approach for Evaluating Turn-On Switching Losses in SiC MOSFET With Kelvin Pin: Concept and Implementation(Institute of Electrical and Electronics Engineers Inc, 2024) Mohammed Cherif, okba; Nadji, Bouchra; Tadjer, Sid Ahmed; Bencherif, HichemWith the progressive adoption of silicon carbide (SiC) power devices in modern power converters, exploiting their superior efficiency, faster switching speed, and higher power density, an understanding of the factors influencing these properties becomes vital. One such critical factor is switching losses, which can drastically affect overall system performance. This study develops and presents a new analytical model for predicting the turn-on switching losses in SiC MOSFETs with Kelvin pin. The proposed model, derived from a carefully constructed set of nonlinear differential equations, accounts for the nonlinearity of the transconductance by incorporating a novel transfer characteristic model. The model also incorporates the nonlinear junction capacitances effects. The developed analytical model allows for the prediction and optimization of turn-on switching losses in SiC MOSFETs, thus enabling improved energy efficiency and reliability. The accuracy of the proposed model is verified through comparison with experimental results obtained using the double pulse test board that was designed and constructed, demonstrating its applicability for the investigation of SiC MOSFET power lossesItem Technical-economic study of PVC-based formulations intended to industrial 3-wire electric cables, using a full factorial design methodology(2023) Cherfi, Abdelhamid; Dehak-Oughlissi, Karima; Ben Meddour, TouhamiIn the present study, full factorial designs were used to model and optimize the mechanical properties of PVC-based formulations constituting three-core power cables: sheathing, insulation and stuffing, while respecting the standards in force, and aiming for a minimum cost. The effects of 4 parameters: plasticizer content (X1), filler content (X2), stabilizing agent content (X3) and the kind of plasticizer were investigated on the following properties: Density (D), Hardness (H), Elongation at break (EB) and Fracture resistance (FR), as well as the price (DA/kg of formulation). The desirability-based optimization gave the following values: EB = 214.72%, FR = 19.94 MPa and Price = 116.71 DA/kg for the sheathing; EB = 198.11%, FR = 4.38 MPa and Price = 61.73 DA/kg for the stuffing; EB = 207.84%, FR = 19.35 MPa and Price = 102.73 DA/kg for the insulation. The study revealed also that the order of significance of the effects on the mechanical properties was: X1>X2>X3 and that the use of cheapest plasticizer did not affect greatly the mechanical propertiesItem Adsorption of malachite green onto walnut shells : kinetics, thermodynamic, and regeneration of the adsorbent by chemical process(Korean Fiber Society, 2023) Merrad, Samiya; Abbas, Moussa; Trari, MohamedThe textile industry produces huge amounts of wastewaters containing synthetic and toxic dyes. The aim of this study was to evaluate the adsorption of Malachite green (MG) onto Activated Carbon from Walnut Shells (ACWS) realized in a batch system. The effects of contact time, initial pH, stirring speed, particle size, temperature, adsorbent dose, and initial MG concentration on the adsorption capacity were investigated graphically for determining optimum conditions. The experimental isotherm data were analyzed by the Langmuir, Freundlich, Temkin, and Elovich models. The adsorption follows well the Langmuir equation, providing a better fit of the equilibrium adsorption data. Under optimized conditions, up to 154.56 mg/g at 25 °C and 370.37 mg/g at 45 °C were removed from the solution. The adsorption mechanism of MG onto ACWS was studied using the first-pseudo-order, second-pseudo-order, Elovich and Webber–Morris diffusion models. The adsorptions’ kinetic was found to follow rather a pseudo-second-order kinetic with a determination coefficient (R2) of 0.999. The adsorption isotherms at different temperatures have been used for the determination of thermodynamic parameters, i.e., the free energy ΔGo (0.802 to − 2.123 kJ/mol), positive enthalpy change ΔHo(18.547 kJ/mol), entropy (ΔSo = 0.064 kJ/molK), and activation energy (Ea = 14.813 kJ/mol). The negative ΔGo and positive ΔHo values indicate that the overall MG adsorption is spontaneous and endothermicItem Robust smart schemes for modeling carbon dioxide uptake in metal - organic frameworks(Elsevier, 2021) Nait Amar, Menad; Ouaer, Hocine; Abdelfetah Ghriga, MohammedThe emission of greenhouse gases such as carbon dioxide (CO2) is considered the most acute issue of the 21st century around the globe. Due to this fact, significant efforts have been made to develop rigorous techniques for reducing the amount of CO2 in the atmosphere. Adsorption of CO2 in metal–organic frameworks (MOFs) is one of the efficient technologies for mitigating the high levels of emitted CO2. The main aim of this study is to examine the aptitudes of four advanced intelligent models, including multilayer perceptron (MLP) optimized with Levenberg-Marquardt (MLP-LMA) and Bayesian Regularization (MLP-BR), extreme learning machine (ELM), and genetic programming (GP) in predicting CO2 uptake in MOFs. A sufficiently widespread source of data was used from literature, including more than 500 measurements of CO2 uptake in13 MOFs with various pressures at two temperature values. The results showed that the implemented intelligent paradigms provide accurate estimations of CO2 uptake in MOFs. Besides, error analyses and comparison of the prediction performance revealed that the MLP-LMA model outperformed the other intelligent models and the prior paradigms in the literature. Moreover, the MLP-LMA model yielded an overall coefficient of determination (R2) of 0.9998 and average absolute relative deviation (AARD) of 0.9205%. Finally, the trend analysis confirmed the high integrity of the MLP-LMA model in prognosticating CO2 uptake in MOFs, and its predictions overlapped perfectly the measured values with changes in pressure and temperatureItem Mass transfer processes in the adsorption of Lead (Pb2+) by apricot stone activated carbon (ASAC) : isotherms modeling and thermodynamic study(Springer, 2021) Abbas, MoussaIn the present study, batch experiments were carried out to elucidate the potential of apricot stone activated carbon ASAC to remove Pb2+ ions from aqueous solution. ASAC was characterized by Bruanauer, Emmett and Teller surface area S = 80.08 (m2/g), Fourier transform infrared spectroscopy and scanning electron microscopy. The effects of various process parameters such as initial pH (2–14), adsorbent dose (5–45 g/L) initial metal ion concentration (20–0 mg/L), contact time (0–90 min), agitation speed (100–700 rpm) and temperature (298–323 k) were investigated in their respective range and their optimum conditions were ascertained. The adsorption kinetics were analyzed by the pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion kinetic models. It was found that the adsorption of the metal ions followed pseudo-second-order kinetic model. The Adsorption isotherms were modeled with Langmuir, Freundlich, Temkin, Hasley and Harkins models and their isotherm constants were calculated. The Freundlich model fits the data with a monolayer adsorption capacity of 166.813 mg/g at pH 8. The thermodynamic parameters such as the Gibbs free energy, enthalpy and entropy were calculated to predict the nature of adsorption process. The calculated thermodynamic parameters showed that the adsorption of Pb2+ ions on ASAC is endothermic (ΔH0 = 121.38 kJ/mol) and not spontaneous (ΔG0 > 0) in natureItem Modeling and control of UAV quadrotor(IEEE, 2019) Zammoum Boushaki, Razika; Aribi, Yacine; Loubar, Hocine; Hamza, Younes; Kouzou, AbdellahSince the advances in technologies and the ability to manufacture miniature sensors and controllers using the Micro-Electro-Mechanical Systems (MEMS) technologies, there have been a lot of advances in the Unmanned Aerial Vehicle (UAV) area. A lot of the research conducted focused on the quadrotor due to its previously mentioned advantages of easier manufacturing, compactness and maneuverability among others. a detailed description of the dynamic modelling of the Quadrotor is presented. Various control strategies like the Proportional Derivative Control, the Sliding Mode Control and the Backstepping Control methods have been elucidated and implemented in MATLAB and SIMULINK. Simulations have been carried out and the results have been presentedItem Application of gene expression programming for predicting density of binary and ternary mixtures of ionic liquids and molecular solvents(ELSEVIER, 2020) Nait Amar, Menad; Ghriga, Mohammed Abdelfetah; Hemmati-Sarapardeh, AbdolhosseinIonic Liquids (ILs) have received increased attention across a number of disciplines in recent years. This noticeable importance of ILs is attributed to their attractive proprieties. Precise evaluation of the thermophysical properties of ionic liquids and their mixtures with molecular solvents is essential for distinct multidisciplinary applications. In this study, a rigorous white-box intelligent technique, viz. gene expression programming (GEP) was implemented for establishing new correlations for accurate prediction of density of binary and ternary mixtures of ILs and molecular solvents. The newly suggested correlations were developed using a comprehensive experimental database with 1985 real measurements under a variety of operational conditions. The obtained results revealed that the newly established GEP-based correlations can predict the density of binary and ternary mixtures of ILs and molecular solvents with a high degree of integrity. The GEP-based correlations exhibited overall average absolute relative error (AARE) values of 0.5621% and 0.2128% for binary and ternary cases, respectively. Besides, it was found that our proposed explicit correlations followed the expected tendency with respect to the considered variables. Furthermore, the superiority and the reliability of the GEP-based correlations was testified against the best-existing approaches in the literature. Finally, the leverage approach was performed and the statistical validity of the correlations and the experimental data was testified.