Journal Articles

Permanent URI for this collection

http://172.16.30.20:4000/handle/123456789/4376

Browse

Now showing 1 - 20 of 52

Open Access
IMPROVING THE PERFORMANCES OF A HIGH TC SUPERCONDUCTING CIRCULAR MICROSTRIP AN- TENNA WITH MULTILAYERED CONFIGURATION AND ANISOTROPIC DIELECTRICS
(Université de M'sila , univ-msila.dz, 2010-12) Benmeddour, Fadila; Bouttout, F
The moment method technique has been improved to in- vestigate the scattering properties of high Tc superconducting circular antennas with anisotropic substrate in multi-layered con¯guration. In this method, the electric ¯eld integral equation for a current element on a grounded dielectric slab of in¯nite extent was developed by basis functions involving Chebyshev polynomials. An improved analytical model is presented taking into account anisotropic substrate, super- conducting material for the circular patch and multilayered structure. To validate the theoretical results, an experimental study has been performed for a perfectly conducting circular patch on a single layer, with and without air gap. Good agreements were obtained between our theory and measurements. E®ects of temperature and thicknessof a superconducting ¯lm are also reported and discussed. The perfor- mances of high Tc superconducting circular antennas were improved by the use of uniaxial anisotropy substrate and multilayer con¯guration.
Open Access
Geometrically tunable slow light based on a modified photonic crystal waveguide
(Université de M'sila, 2017) Mouhssin, Maache
In this paper, we have proposed a design for slow light in a modified photonic crystal waveguide by inserting reduced air holes along the middle of the waveguide with a half period of the lattice and by shifting the second rows of holes toward the center of the modified waveguide. A wideband slow light with a high group index and low group velocity dispersion has been achieved. A nearly constant group index of 21, 20, 35.5 and 65 over 20.3 nm, 15.6 nm, 9.5 nm, 5.3 nm bandwidth in the environment of 1550 nm, respectively, are also obtained.
Open Access
Grey Wolf based control for speed ripple reduction at low speed operation of PMSM drives
(Université de M'sila, 2018) Djerioui, Ali; Houari, Azeddine; Ait-Ahmed, Mourad; Benkhoris, MOHAMED-FOUAD; Chouder, Aissa
Speed ripple at lowspeed-high torque operation of PermanentMagnet SynchronousMachine (PMSM) drives is considered as one of the major issues to be treated. The presented work proposes an efficient PMSMspeed controller based on Grey Wolf (GW) algorithm to ensure a high-performance control for speed ripple reduction at low speed operation. The main idea of the proposed control algorithm is to propose a specific objective function in order to incorporate the advantage of fast optimization process of the GW optimizer. The role of GW optimizer is to find the optimal input controls that satisfy the speed tracking requirements. The synthesis methodology of the proposed control algorithm is detailed and the feasibility and performances of the proposed speed controller is confirmed by simulation and experimental results. The GW algorithm is a model-free controller and the parameters of its objective function are easy to be tuned. The GWcontroller is compared to PI one on real test bench. Then, the superiority of the first algorithm is highlighted.
Open Access
Design of a Selective Smart Gas Sensor Based on ANN-FL Hybrid Modeling
(Université de M'sila, 2018) S., Kouda
In this paper, we propose the modeling of an industrial gas sensor “MQ-9”, where our modeling is based on ANNs “artificial neural networks”. The gas sensor model, obtained, operated under a dynamic environment and expresses accurately the MQ-9 gas sensor behavior. Accordingly, it takes into account the nonlinearity and the cross sensitivity in gas selectivity, temperature and humidity. This model is implemented into PSPICE “performance simulation program with integrated circuit emphasis” simulator as an electrical circuit in order to prove the similarity of the analytical model output with that of the MQ-9 gas sensor.
Open Access
First principles investigation of optoelectronic properties of ZnXP2 (X = Si, Ge) lattice matched with silicon for tandem solar cells applications using the mBJ exchange potential
(Université de M'sila, 2018) Bennacer, Hamza
II-IV-V2 materials are attractive compounds for optoelectronic, photonic and photovoltaic applications due to their valuable ternary chemistry. A primary technological challenge in photovoltaics is to find and develop a lattice matched efficient material to be used in combination with silicon for tandem solar cells. ZnSiP2 and ZnGeP2 chalcopyrites are promising semiconductors that could satisfy these criteria. Particularly, ZnSiP2 is known to have bandgap energy of ∼2 eV and a lattice mismatch with silicon of 0.5%. In this work, the first principle calculations have been performed to investigate the structural, electronic and optical properties of ZnSiP2 and ZnGeP2 in chalcopyrite structure within the Full Potential- Linearized Augmented Plane Wave (FP-LAPW) method based on the Density Functional Theory (DFT) as implemented in WIEN2K code. The local Density approximation (LDA) of Perdew and Wang was used as exchange-correlation potential to calculate the structural proprieties. Furthermore, the recently modified Becke-Johnson (mBJ) functional of Tran and Blaha was also employed to compute the electronic and optical properties in order to get best values of the band gap energy and some better degree of precision. The complex dielectric function, the complex refractive index, reflectivity, absorption coefficient, and the optical conductivity were calculated to illustrate the linear optical properties of both compounds ZnSiP2 and ZnGeP2. At last, the obtained results indicate that ZnSiP2 and ZnGeP2 are attractive materials in optoelectronic devices especially as a lattice matched material with silicon for tandem solar cells applications.
Open Access
Souhil KOUDA
(Université de M'sila, 2018) Souhil, KOUDA
In this paper, we propose the modeling of an industrial gas sensor “MQ-9”, where our modeling is based on ANNs “artificial neural networks”. The gas sensor model, obtained, operated under a dynamic environment and expresses accurately the MQ-9 gas sensor behavior. Accordingly, it takes into account the nonlinearity and the cross sensitivity in gas selectivity, temperature and humidity. This model is implemented into PSPICE “performance simulation program with integrated circuit emphasis” simulator as an electrical circuit in order to prove the similarity of the analytical model output with that of the MQ-9 gas sensor.
Open Access
QUANTIFYING BABY CRYING RHYTHM ABNORMALITIES USING MULTILAYER PERCEPTRON
(Université de M'sila, 2018) Dahmani, Habiba
There are no studies to quantify rhythm of baby crying signals until now. In the present study, we propose that the introduction of the temporal rhythm metrics as used in the languages identification domain may well characterize the rhythm of newborn infant's sounds. Then, it may improve diagnostic accuracy and helps quickly identify, categorize and discriminate between the sick and healthy babies, therefore, provide more reliability to the evaluation of the health of the newborns. The repeated bursts of expiratory sounds were detected and selected from the crying records of 295 full-term babies of 1 to 90 days old. These recordings occur under some stimulus as pain, fever, diaper change and other different states. The relevance of the proposed rhythm features to distinguish the healthy from the sick babies is approved. The results of various classification experimentations of the correct classification were more than 80%. Indeed, the findings were very promising and confirm the ability of rhythm parameters to characterize the baby crying signal well.
Open Access
Efficient magneto-optical TE/TM mode converter in a hybrid structure made with a SiO2/ZrO2 layer coated on an ion-exchanged glass waveguide
(Université de M'sila, 2018) Bouras, Mounir
The TE-TM mode conversion is an important requirement for magneto-optical waveguide devices. In this work, we report on the theoretical study of magneto-optical waveguides on an ion-exchanged glass waveguide. This study explores the possibility to realize a mode converter TE-TM on a hybrid structure. This hybrid device is made by coating a SiO2/ZrO2 layer doped with magnetic nanoparticles on an ion-exchanged glass waveguide. It has been analyzed by means of a beam propagation method for numerical solution of the full-vectorial wave equation. We have also used the transparent boundary condition. The mode converters TE-TM based on the Faraday rotation and modal birefringence are then numerically simulated. Depending on the increasing of nanoparticles volume fraction in the SiO2/ZrO2 layer and on decreasing the modal birefringence of the hybrid structure, the TE-TM conversion efficiency varies from several percent to several tens of percent. © 2017 Published by Elsevier GmbH
Open Access
Miniaturization of a PIFA Antenna for Biomedical Applications Using Artificial Neural Networks
(Université de M'sila, 2018-04) DJELLID, Asma
This work deals with the optimization of an inverted F dual-band implantable antenna operating in Medical Device Radiocommunications Service (MedRadio, 401–406 MHz) and Industrial Scientific Medical (ISM, 902–928 MHz) applications bands. Artificial neural networks (ANNs) are implemented to minimize the size of the initial design. The ANN’s output with the physical and dielectric parameters of antenna as inputs is tested using COMSOL Multiphysics . The obtained results regarding the return loss S11, resonant frequency and bandwidth of the antenna are presented and discussed. Indeed, the size of the antenna is reduced by 21.48% with respect to the initial size while preserving its initial good performance in both frequency bands.
Open Access
Incremental Banerjee test conditions committing for robust parallelization framework
(Université de M'sila, 2018-05) Haddi, BAKHTI; Aimad Eddine, DEBBI
This paper describes the design of an automatic parallelization framework. The kernel supplied at its front end was suggested as an instrument for parallel potential assessment. It was used to measure the maximum achievable speedups in the major set of the CHStone benchmark suite programs. In such framework, we suggested the liberation of parallelism incrementally. We proposed a data dependency heuristic-based transformation method to make true dependences dissociation. We generated an internal representation (IR2 ), where the Banerjee test conditions are met. Two among three of Banerjee test conditions came to be committed. In shared memory many/multicore platforms, the third condition could be satisfied by privatization. We would be able to choose the safe and the opportune pairwise (mapping-privatization) scheme among a number of threads mapping scenarios that become available in the IR2 structure. Instrumentation on a subset of CHStone benchmark was carried out as a validity proof of our proposal, and the results confirmed that our framework kernel is robust
Open Access
Effect of the Thickness of High Tc Superconducting Rectangular Microstrip Patch Over Ground Plane with Rectangular Aperture
(Université de M'sila, 2018-06) BOUKHENNOUFA, Nabil
of new materials in microwave technology. Particularly, a special interest has been observed in the use of superconducting materials in microwave integrated circuits, this is due to their main characteristics. In this paper, the complex resonant frequency problem of a superconductor patch over Ground Plane with Rectangular Aperture is formulated in terms of an integral procedure is used in the resolution of the electric field integral equation. The surface impedance of the superconductor film is modeled using the two fluids model of Gorter and Casimir. Numerical results concerning the effect of the thickness of the superconductor patch on the characteristics of the antenna are presented.
Open Access
Resonant Characteristics of Circular HTC Superconducting Printed Antenna Covered with a Dielectric Layer
(Université de M'sila, 2018-07-23) BENMEDDOUR, Fadila
Effects of a superstrate layer on the resonant frequency and bandwidth of a high Tc superconducting (HTS) circular printed patch are investigated in this paper. For that, a rigorous full-wave spectral analysis of superconducting patch in multilayer configuration is described. In such an approach, the spectral dyadic Green’s function which relates the tangential electric field and currents at various conductor planes should be determined. Integral equations are solved by a Galerkin’s moment method procedure, and the complex resonance frequencies are studied with basis functions involving Chebyshev polynomials in conjunction with the complex resistive boundary condition. To include the superconductivity of the disc, its complex surface impedance is determined by using London’s equation and the model of Gorter and Casimir. Numerical results are compared with experimental results of literature as well as with the most recent published calculations using different methods. A very good agreement is obtained. Finally, superstrate loading effects are presented and discussed showing interesting enhancement on the resonant characteristics of the superconducting antenna using combinations of Chebyshev polynomials as set of basis functions. 1.
Open Access
Resonant Characteristics of Circular HTC Superconducting Printed Antenna Covered with a Dielectric Layer
(Université de M'sila , univ-msila.dz, 2018-09-18) Benmeddour, Fadila; Christophe, Dumond; Kenane, Elhadi
Effects of a superstrate layer on the resonant frequency and bandwidth of a high Tc superconducting (HTS) circular printed patch are investigated in this paper. For that, a rigorous full-wave spectral analysis of superconducting patch in multilayer configuration is described. In such an approach, the spectral dyadic Green’s function which relates the tangential electric field and currents at various conductor planes should be determined. Integral equations are solved by a Galerkin’s moment method procedure, and the complex resonance frequencies are studied with basis functions involving Chebyshev polynomials in conjunction with the complex resistive boundary condition. To include the superconductivity of the disc, its complex surface impedance is determined by using London’s equation and the model of Gorter and Casimir. Numerical results are compared with experimental results of literature as well as with the most recent published calculations using different methods. A very good agreement is obtained. Finally, superstrate loading effects are presented and discussed showing interesting enhancement on the resonant characteristics of the superconducting antenna using combinations of Chebyshev polynomials as set of basis functions.
Open Access
Real time implementation of fuzzy gain-scheduled PID controller for twin rotor MIMO system (TRMS)
(Université de M'sila, 2018-12) Mohammed Zinelaabidine, Ghellab
The work has done in this paper concern a strategy of control based on gain adaptive proportional integral derivative (PID) using the fuzzy inference system and their application to the Twin Rotor MIMO System (TRMS), the PID controller with fixed parameters may fail to provide acceptable control performance. To improve the PID control effect, new designs of the fuzzy gain Scheduled PID controller (FGSPID) were presented in this paper. The proposed techniques were applied to the TRMS, where adaptive PID controllers were proposed for control system in the presence of external disturbances. The parameters of PID controller were adjusted by a fuzzy system, used to tune in real-time the controller gain. The obtained simulation and experiment results show that the robustness of TRMS angles (pitch and yaw) driven by proposed controller are guaranteed.
Open Access
Estimators of compound Gaussian clutter with lognormal texture
(Université de M'sila, 2019) Izzeddine, Chalabi
Estimators of clutter models parameters based upon higher order moments estimator (HOME) produce usually poor results in particular for low sample sizes. In an attempt to remedy this situation, closed forms of [zlog(z)] and fractional order moments estimator (FOME) are derived in this work and yield a good estimation accuracy of parameters of the compound Gaussian clutter with log-normal texture (CG-LNT). Using simulated and real data, estimation comparisons show that best values of mean square error (MSE) and bias are achieved using the proposed procedures.
Open Access
A unified framework for the performance evaluation of single-branch dual-hop AF relaying in the presence of transceiver hardware impairments
(Université de M'sila, 2019) Slimane, Benmahmoud
In this paper, a general four-parameter end-to-end signal-to-noise with distortion ratio (SNDR) model for single-branch dual-hop amplify-and-forward (AF) relaying with/without the presence of transceiver hardware impairments is proposed. This model encompasses standard as well as non-standard AF relay configurations for both ideal and non-ideal transceiver hardware cases. A unified framework to evaluate the performance of single-branch dual-hop AF relaying is then formulated. This is accomplished by deriving new closed-form expressions for some statistics of some functions of two independent Gamma random variables. Based on these closed-form expressions, an exact analytical expression for the outage probability (OP) and an upper bound for the ergodic capacity are derived. Monte Carlo simulations’ results are provided to verify the accuracy of the analytical results
Open Access
Distributed CA-CFAR and OS-CFAR Detectors Mentored by Biogeography Based Optimization Tool
(Université de M'sila, 2019) Amel Gouri
In this paper, distributed constant false alarm rate (CFAR) detection in homogeneous and heterogeneous Gaussian clutter using Biogeography Based Optimization (BBO) method is analyzed. For independent and dependent signals with known and unknown power, optimal thresholds of local detectors are computed simultaneously according to a preselected fusion rule. Based on the Neyman-Pearson type test, CFAR detection comparisons obtained by the genetic algorithm (GA) and the BBO tool are conducted. Simulation results show that this new scheme in some cases performs better than the GA method described in the open literature in terms of achieving fixed probabilities of false alarm and higher probabilities of detection
Open Access
Neighborhood Component Analysis and Support Vector Machines for Heart Disease Prediction
(Université de M'sila, 2019) Mohamed Djerioui; Youcef Brik; Mohamed Ladjal; Bilal Attallah
Nowadays, one of the main reasons for disability and mortality premature in the world is the heart disease, which make its prediction is a critical challenge in the area of healthcare systems. In this paper, we propose a heart disease prediction system based on Neighborhood Component Analysis (NCA) and Support Vector Machine (SVM). In fact, NCA is used for selecting the most relevant parameters to make a good decision. This can seriously reduce the time, materials, and labor to get the final decision while increasing the prediction performance. Besides, the binary SVM is used for predicting the selected parameters in order to identify the presence/absence of heart disease. The conducted experiments on real heart disease dataset show that the proposed system achieved 85.43% of prediction accuracy. This performance is 1.99%higher than the accuracy obtained with the whole parameters. Also, the proposed system outperforms the state-of-the-art heart disease prediction
Open Access
Optimal PatternSynthesisofLinearAntennaArrays Using ModifiedGreyWolfOptimizationAlgorithm
(Université de M'sila, 2019) Lakhlef, Nora
The aim of this work is to show the effectiveness of a new algorithm named as modified grey wolf optimization (MGWO) algorithm to determine the optimum combination parameters values of a linear antenna array which is widely used in the communication systems. The selection part of the classical GWO has been modified by adopting the competitive exclusion selection inspired from genetic algorithm. The objective to be attained is a directional array factor with a very low level of lateral lobs. To this effect, a Gaussian function centered at 90° with the total absence of secondary lobs is considered as a desired diagram in our simulation. To matches the desired pattern as closely as possible, we considered the optimization of interspacing elements, weights amplitude and phase excitation of the linear antenna array factor. It has been demonstrated that the performance of a printed linear antenna array depends on all parameters, in which simultaneous optimization is imperative to maximize its characteristics. The obtained results show the effectiveness and the flexibility of the proposed algorithm in terms of minimized lateral lobe level compared to PSO algorithm and the convergence speed towards the desired solution.
Open Access
Multimodel ensemble approach for hourly global solar irradiation forecasting
(Université de M'sila, 2019) Nahed, Zemouri; Hassen, Bouzgou; Christian A., Gueymard
This contribution proposes a novel solar time series forecasting approach based on multimodel statistical ensembles to predict global horizontal irradiance (GHI) in short-term horizons (up to 1 hour ahead). The goal of the proposed methodology is to exploit the diversity of a set of dissimilar predictors with the purpose of increasing the accuracy of the forecasting process. The performance of a specific multimodel ensemble forecast showing an improved forecast skill is demonstrated and compared to a variety of individual single models. The proposed system can be applied in two distinct ways. The first one incorporates the forecasts acquired from the different forecasting models constituting the ensemble via a linear combination (combination-based). The other one consists of a novel methodology that delivers as output the forecast provided by the specific model (involved in the ensemble) that delivers the maximum precision in the zone of the variable space connected with the considered GHI time series (selection-based approach). This forecasting model is issued from an appropriate division of the variable space. The efficiency of the proposed methodology has been evaluated using high-quality measurements carried out at 1min intervals at four radiometric sites representing widely different radiative climates (Arid, Temperate, Tropical, and High Albedo). The obtained results emphasize that, at all sites, the proposed multi-model ensemble is able to increase the accuracy of the forecasting process using the different combination approaches, with a significant performance improvement when using the classification strategy.