Publications Scientifiques et Pédagogiques

Permanent URI for this community

http://172.16.16.5:4000/handle/123456789/363

Browse

Now showing 1 - 20 of 153

A Generic Fuzzy-Based Recommendation Approach (GFBRA)
(International Journal of Fuzzy System Applications, 2022) BOUACHA Ismail
Recommender systems aim to automatically provide users with personalized information in an overloaded search space. To dual withvagueness and imprecision problems inRS, severalresearches have proposed fuzzy- based approaches. Even though these works have incorporatedexperimental evaluation, they were used in differentrecommendations cenarios which makes it difficult to have a fair comparison between them. Also, some of them performed anitems and/or users clustering before generating recommendations. For this reason,they need additional information such as item attributes or trustbetween users which are not always available. Inthispaper, theauthors propose to use fuzzy set techniques to predict the rating of a target user for each unrated item.It uses the target user’shistory in addition with rating of similar users which allows to the target user to contribute in the recommendation process. Experimental results on several datasets seem to be promising in term of MAE (meanaverageerror), RMSE (root mean square error), accuracy, precision, recall, andf-measure
A Novel Fault Diagnosis of Uncertain Systems Based on Interval Gaussian Process Regression: Application to Wind Energy Conversion Systems
(IEEE Access, 2020-12) HARKAT Mohamed Faouzi (Co-Auteur)
Fault detection and diagnosis (FDD) of wind energy conversion (WEC) systems play an important role in reducing the maintenance and operational costs and increase system reliability. Thus, this paper proposes a novel Interval Gaussian Process Regression (IGPR)-based Random Forest (RF) technique (IGPR-RF) for diagnosing uncertain WEC systems. In the proposed IGPR-RF technique, the effective interval-valued nonlinear statistical features are extracted and selected using the IGPR model and then fed to the RF algorithm for fault classi cation purposes. The proposed technique is characterized by a better handling of WEC system uncertainties such as wind variability, noise, measurement errors, which leads to an improved fault classi cation accuracy. The obtained results show that the proposed IGPR-RF technique is characterized by a high diagnosis accuracy (an average accuracy of 99.99%) compared to the conventional classi ers.
A Novel Micro-Thermophotovoltaic Combustor of Hydrogen–Air to Enable Ultra-Lean Combustion, High Thermal Output and NO Low Emissions
(International Journal of Energy Research, 2025-01) AZZOUZ Salaheddine (Co-Auteur)
This study presents a novel micro-combustor (MC) design called micro-trapped vortex combustor (MTVC) for microthermophotovoltaic (MTPV) devices used in small-scale electricity generation. Traditional MC designs struggle to operate efficiently under ultra-lean regimes due to flame quenching, limiting their performance. The proposed MTVC incorporates the trapped vortex concept, inspired by aeronautical applications, to improve thermal performance and stability under ultra-lean conditions. Numerical simulations, using the Navier–Stokes and energy equations for laminar and reactive flow, are conducted to compare the MTVC with conventional micro-backward-step combustors (MBSCs) under hydrogen (H2)–air mixture combustion. The study focuses on key performance parameters such as temperature distribution, heat recirculation, flame shape, flow topology, radiative power and emissions. The results show that the MTVC can operate at an ultra-lean equivalence ratio of Φ=0.5, while the MBSC experiences flame quenching below Φ=0.7. The MTVC design achieves up to 26.51% higher radiative power and a 36% improvement in energy conversion efficiency compared to traditional combustor designs. Additionally, the MTVC produces 43% less nitrogen oxides (NOx) emissions, demonstrating its potential for both higher efficiency and reduced environmental impact in portable power applications.
A Numerical Study of the Efficiency of the Sono Galvano-Fenton Process as a Tertiary Treatment Technique for the Wastewater Reuse in Agriculture
(The Eurasia Proceedings of Science, Technology, Engineering & Mathematics (EPSTEM), 2023) KERBOUA Kaouther
In the present study, the Sono-Galvano-Fenton process is studied numerically as a tertiary treatment process for treated wastewater reuse in irrigation, with in situ generation of the Fenton’s reagent and catalyst, i.e., H2O2 and Fe2+. The sonochemical pathway is examined as a source of hydrogen peroxide under the pre optimized condition of acoustic frequency, 200 kHz. The macroscopic model accounting for the performance of the single acoustic cavitation bubble and the bubble population density is combined with the Fe/Cu galvanic cell operating in acidic conditions (pH 3), following a cumulative and instantaneous production approach in terms of Fenton’s reagent. The combination is optimized based on the rate of hydroxyl radicals generated by the Galvano-Fenton process, as a non-selective powerful oxidant against recalcitrant pollutants, then considering the synergetic effect of the hybrid process in terms of HO● pumped sonochemically and via the Fenton based pathway, treated using simulations of the isolated processes then their combined configuration following both aforementioned approaches
Accuracy improvement of the inSAR quality-guided phase unwrapping based on a modified PDV map.
(Computer Vision Center / Universitat Autonoma de Barcelona, Barcelona, Spain, 2021) Mayache Hichem
In this paper, an accuracy improvement of the quality-guided phase unwrapping algorithm is proposed. Our proposal is based on a modified phase derivative variance which provides more details on local variations especially for vital patterns such as fringes and edges, hence distorted regions may be re-unwrapped according to this new reliable PDV. The proposed improvement is not only effective on accuracy but also on time, the obtained results have shown that the running time with our proposal is less than that of a skillful optimization based algorithm. In order to validate the effectiveness of the proposed approach, the experimental test is carried out on simulated and real data, then a comparison is conducted using several relevant criteria.
Acoustic Cavitation and Ionic Liquid Combined: A Modeling Investigation of the Possible Promises in Terms of Physico-Chemical Effects †
(Engineering. Proceedings, 2023) KERBOUA Kaouther
The present work is based on a mathematical model describing a single acoustic cavitation bubble oscillating under an ultrasonic field of 200 and 300 kHz and an acoustic amplitude of 1.8 atm within 1-butyl-3-methylimidazolium acetate. The model integrates the dynamics of bubble oscillation, the thermodynamics applied to the interior of the bubble and at its interface, and the sonophysical and sonochemical events occurring in the presence of dissolved cellulose in the ionic liquid. The performed simulations shed light on the major physical effects of acoustic cavitation, namely the shockwave and microjet, as well as the sonochemical effects in terms of the degradation rate of the dissolved cellulose in the secondary reactional site, i.e., the interface. The predominance of the effects and its dependency of the acoustic frequency is tackled from an energetic point of view. It is demonstrated that 300 kHz offers the lowest heat flow across the bubble interface, lowering the chances for the sonochemical degradation of cellulose, while 200 kHz offers a significant degradation rate, attaining 71.4 mol·dm−3·s−1, as well as harsher microjets and shockwaves with powers of 3300 and 900 mWatcollapse, respectively
Adigital twin-based energy-efficient wireless multimedia sensor network for waterbirds monitoring
(Elsevier B.V. This is an open access article under the CC BY license, 2024-02-12) DOGHMANE Noureddine
Wetlands play a critical role in maintaining the global climate, regulating the hydrological cycle, and protecting human health. However, they are rapidly disappearing due to human activities. Waterbirds are valuable bio indicators of wetland health, but it is challenging to monitor them effectively. Wireless Multimedia Sensor Networks (WMSNs) offer a promising technology for monitoring wetlands. Nonetheless, these networks are constrained in terms of energy, and also encounter challenges associated with large-scale deployments under natural environmental conditions. These conditions introduce harsh circumstances that may not have been anticipated during the pre-deployment testing phase. This paper proposes a Digital Twin (DT) based energy efficient WMSN monitoring system specifically tailored for waterbirds in wetlands. The system utilizes a unique approach that combines local audio identification and image compression with DT technology to optimize network performance and minimize energy consumption. To reduce unnecessary image transmissions, the system employs a real-time, low-complexity local audio identification phase before triggering image capture. A denoising step is employed to achieve highly accurate bird recognition despite surrounding noises. Each image undergoes a low- omplexity compression scheme prior to transmission, further enhancing energy efficiency. To enhance the system’s overall efficiency and effectiveness, DT technology is integrated to create real-time replicas of the WMSN and the monitoring application. A synergistic interaction between the two DTs enables cooperative data-making decision that ensures both QoS (Quality of Service) and QoE (Quality of Experience) requirements are met. Transmission rate control is done using a fuzzy logic decision-making technique. Real time feedback provides rapid and accurate analysis of the current state of the WMSN, allowing for dynamic adjustments. The "what-if scenarios" feature of the implemented DTs has been effectively leveraged to find the most suitable settings for the controller. The effectiveness and performance enhancements achieved by integrating DT into our WMSN-based surveillance system are validated through comprehensive experiments in scenarios that correspond to a real-world wetland. Comparative analyses demonstrate the undeniable benefits of the DT-integrated system compared to a conventional WMSN-based surveillance setup. In particular, the results demonstrate the system’s superior performance in terms of energy efficiency, real-time monitoring capabilities, and ability to handle multiple video sources.
An Associated and Nonassociated Flow Rule Comparison for AISI 439- 430TI Forming: Modeling and Experimental Analysis
(Latin American Journal of Solids and Structures, 2021) MATOUGUI Nedjoua (Co-Auteur)
The plastic anisotropy behavior of ferritic stainless steel (FSS) sheets was analyzed and modeled under associated and nonassociated flow rule approaches. Three orthotropic flow functions, known as quadratic Hill48 and nonquadratic (Yld2000-2d and BBC2005), were developed and employed under an associated and nonassociated flow rule hypothesis. For the NAFR based on the initial anisotropy, the mechanical behavior was described by the nonexponential model functions of Yld2000-2d and BBC2005 to predict the directional dependence of mechanical parameters. It provided a considerable advantage in terms of flexibility and good agreement with the experiment. According to the results, the polynomial fit functions of the transverse versus longitudinal true plastic strain curve were used to describe the designated properties corresponding to a selected level of strain. To describe the evolution of anisotropic hardening and potential plastic hardening, seven different loading conditions were considered. The proposed evolutionary non-AFR Yld2000-2d and BBC2005 criteria showed good accuracy in predicting the evolution of hardening yield and Lankford coefficients depending on the plastic deformation.
An Extension of Left Radau Type Inequalities to Fractal Spaces and Applications
(Licensee MDPI, Basel, Switzerland., 2024-09-23) LAKHDARI Abdelghani
In this study, we introduce a novel local fractional integral identity related to the Gaussian two-point left Radau rule. Based on this identity, we establish some new fractal inequalities for functions whose first-order local fractional derivatives are generalized convex and concave. The obtained results not only represent an extension of certain previously established findings to fractal sets but also a refinement of these when the fractal dimension µ is equal to one. Finally, to support our findings, we present a practical application to demonstrate the effectiveness of our results.
An Extension of Left Radau Type Inequalities to Fractal Spaces and Applications
(axioms, 2024-09) KARABADJI Nour El Islem (Co-Auteur)
In this study, we introduce a novel local fractional integral identity related to the Gaussian two-point left Radau rule. Based on this identity, we establish some new fractal inequalities for functions whose first-order local fractional derivatives are generalized convex and concave. The obtained results not only represent an extension of certain previously established findings to fractal sets but also a refinement of these when the fractal dimension μ is equal to one. Finally, to support our findings, we present a practical application to demonstrate the effectiveness of our results.
Analyses of entropy generation for a solar minichannel flat plate collector system using different types of nanofluids
(Journal of Computational Applied Mechanics, 2021) AZZOUZ Salaheddie (Co-Auteur)
The working fluid plays a major role in improving the efficiency of the energy system, so the method and criteria of choice are extremely important. Nevertheless, these methods are usually based on the First Law of Thermodynamics (FLT), while the concepts of entropy and irreversibility on which the Second Law of Thermodynamics (SLT) is based are often ignored in the choice of the fluid. In this paper, a new approach is proposed to select a fluid among a group of fluids in order to use it as a working fluid in a Minichannel Flat Plate Solar Collector (MFPSC). For this, a numerical simulation was performed on a fluid in laminar flow in a small rectangular channel subjected to a uniform heat flux of (1000 W/m2). The use of Computational Fluid Dynamics (CFD) based on the finite volume method was implemented to solve the governing equations. The essential parameters on which the selection is based are the entropy generation (Sgen), the irreversibility of entropy generation number (Ns), the Bejan number (Be), and the Energy Performance Criterion (EPC). The analyses were performed on a group of five fluids two conventional (water and methanol), the rest are nanofluids (Al2O3-H2O, CuO-H2O, and Fe3O4 -H2O). Multiple parallel computation phases are defined by user-defined functions (UDFs) for all fluids. It is found that nanofluids offer higher heat transfer ability than conventional fluids, and the behavior of the nanofluid (CuO-H2O) shows on average a minimum total entropy generation (minimum irreversibility) compared to other fluids (conventional and nanofluids), which reduces the energy degradation and improves the heat transfer. Therefore, it is chosen as the working fluid for the MFPSC.
Analysis and improvement of the fragmentation quality of blasted rock using digital image processing: the case of the Kef Lahmer quarry, N-E Algeria
(Geomatics, Landmanagement and Landscape, 2024) BATOUCHE Toufik (Co-Auteur)
The mining industry plays a significant role in the extraction and processing of various ore materials (phosphate, copper, iron, gold, aggregates and others), contributing to industrial and economic development. Rock fragmentation is a fundamental operation and a complex element in mining activities influenced by multiple parameters, including geological and geometric factors, explosive load parameters, and others related to the details of the execution of the blasting plan. The effectiveness of blasting depends on factors such as the geological structure, volume, optimal size of rocks to be blasted, and compliance with safety conditions. To achieve desirable outcomes, it is crucial to make informed decisions regarding the types and quantities of explo-sives to be used, along with other principal parameters of drilling-blasting design. Continuous evaluation of rock fragmentation is essential for optimizing blasting plans by contributing to the improvement of the quality-price ratio under favorable environmental and safety conditions. This study aims to analyze and enhance the quality of rock fragmentation resulting from blasting activities in the Kef Lahmar-Setif limestone quarry (northeast Algeria), which is characterized by significant rock mass fracturing. This fracturing will be carefully analyzed in order to arrive at an accurate blasting plan for the structure of the studied rock massif. As the aim of the research is to optimize the blasting plan to generate maximum gas pressure and minimize shock pressure due to the existing fractures in the rock mass. in order to test this hypothesis, we conducted sev eral blasting tests by modifying the charge rate of the explosives used (Anfomil and Marmanite III), while maintaining the same parameters in the blasting plan for each test. The goal was to achieve optimal fragmentation. The particle size of the blasted rock pile was analyzed using WipFrag software, which utilizes image analysis techniques
Analysis of the compromise between cutting tool life, productivity and roughness during turning of C45 hardened steel
(PRODUCTION ENGINEERING ARCHIVES, 2021) ABIDI Youcef
Tool wear and surface roughness as performance indexes are considered to be the most important in terms of hardened materials’ machinability. The best combination of cutting parameters which en hances the compromise between tool life, productivity and machined surface quality contribute to benefice on production cost, which makes manufacturing industry interested in it. The aim of this research is to investigate the life of ceramic cutting tool and machining productivity together with surface roughness during turning of hardened steel C45, with focus on the selection of the optimal cutting parameter combination. The experiments are carried out based on uni-factorial planning meth odology of cutting speeds and feed rates. The results show that the mixed ceramic tool is suitable for turning hardened steel C45 (40 HRC) and the conclusion is that it performed well in terms of tool life, productivity and surface quality at a combination of cutting speed (200 m/min), feed (0.08 mm/rev) and depth of cut (0.3 mm). Additionally, a tool life model has been proposed which is presented very high coefficient of determination.
ANALYSIS OF THE ENVIRONMENTAL IMPACT OF PHOSPHATE MINING ON THE EXAMPLE OF DJEBEL ONK DEPOSIT (TEBESSA), ALGERIA
(TECHNOLOGY AUDIT AND PRODUCTION RESERVES, 2024-01) NETTOUR Djamel (Co-Auteur)
The object of the study is natural phosphates, which play a major role in various industrial sectors, ranging from agriculture to pharmaceuticals, via the metallurgy and chemistry. In Algeria, their importance in the international market is significant, thanks to the deposits of Djebel Onk, located in the south-eastern part of the region of Tebessa. However, the mining and processing of these phosphates lead to waste significant, both in liquid form than in solid, raising significant environmental concerns. In this perspective, a thorough analysis is necessary for a rational and ard reliable, ensuring the preservation of the environment. This research was undertaken to quantify and analyze the distribution of various heavy metals in the phosphate waste generated by ebel Onk plant (Kef Essennoun deposit). These wastes are crucial to achieve the objectives of sustainable development in relation to public health and the environment. The work focuses on the study of samples of the different releases of the treatment processes. These latter were subjected to a characterization of different analysis techniques, qualitative and quantitative, namely: XRD, IR, XRF, SEM and AAS. The results obtained distinguish differences are notable between the levels recorded by the raw phosphate and those samples wastes of treatment processes. Thus, the waste produced consists of 59.2 % dolomite, 20.5 % calcite, and 19.8 % fluorapatite. The presence of kaolinite was also noted in these residues, though in a small proportion (0.5 %). It has also been noted that these concentration of the elements in trace metal increases relatively with the decrease of the diameter of the grain size, in particular in the mud. This shows that the efficiency of the modes of treatment will allow for some cases, reduce the concentration of elements in the phosphate studied. This opens up promising research opportunities for scientists and engineers to develop more efficient and advanced treatment methods.
Analytical Modeling of Joule Heating in Electro-Thermal Contacts for Short-Term Industrial Applications
(International Journal of Heat and Technology, 2024) BENCHADLI Djillali; AZZOUZ Salaheddine (Co-Auteur)
the thermal transfer at solid-solid interfaces, particularly with heat generation at the interface, is a critical area of study. This research presents a theoretical framework for addressing the direct problem of thermal conduction in electro-thermal contacts, with a focus on short-term scenarios where heat dissipation occurs through the Joule effect. This aspect, not extensively explored in existing literature, is investigated using a semi analytical method. The study also encompasses a simulation-based exploration, aimed at deepening the understanding of physical phenomena at the contact level. Special attention is given to the thermal transfers initiated at the asperity level of the electro-thermal contact. Findings from this investigation underscore the significance of incorporating the thermal diffusivity of materials into the model for achieving convergence. A notable observation is the increasing divergence over time between the temperatures predicted by numerical and analytical solutions, a trend more pronounced in materials with higher thermal diffusivity, such as titanium. This research contributes valuable insights into the modeling of contact parameters essential for simulating various industrial applications, potentially enhancing efficiency and efficacy in thermal engineering practices.
Analyzing Pillar Strength and Behavior using Wolfram Mathematica code: Effects of Cracks, Size and Discretization
(Acta Monstanistica Slovaca, 2024) CHENITI Hamza (Co-Auteur)
The stability of fractured rock masses and the modeling of underground mining pillars necessitate a comprehensive understanding of behavioral models and mechanical properties. This study employs the Wolfram Mathematica code to investigate mining pillar reliability, specifically focusing on elucidating the influence of scale and shape on pillar strength. Drawing inspiration from methodologies in the existing literature, our approach is based on the Mohr-Coulomb theory and Griffiths's random field of rock strength. This study highlights the significance of shape, where pillar strength exhibits exponential growth with increasing width-to-height ratios. Beyond a critical value, strength surges, especially under elevated confining stress. Additionally, a critical mesh size significantly affects the weakest pillar behavior. Our results confirm the 'size effect,' wherein strength generally decreases with increasing pillar volume. Thus, strength decreases with rising volume until a threshold. Particularly noteworthy is the phenomenon observed in the presence of cracks; initially, an increase in mesh size leads to a decline in strength, corresponding to an increase in the number of cracks. However, this decline stabilizes beyond a critical mesh size, after which strength experiences a resurgence echoing behavior seen in the homogeneous case. In this paper, the reproduction of the scale effect by an algorithm based on the Mathematica code was made to allow a probabilistic study to be carried out because of the random existence of discontinuities in nature – another hand to carry out stochastic modeling of fractures and its influence on the rock mass strength.
Anexpandedanalysis of local fractional integral inequalities via generalized (s, P)-convexity
(Journal of Inequalities and Applications, 2024) LAKHDARI Abdelghani
This research aims to scrutinize specific parametrized integral inequalities linked to 1, 2, 3, and 4-point Newton-Cotes rules applicable to local fractional differentiable generalized (s,P)-convex functions. To accomplish this objective, we introduce a novel integral identity and deduce multiple integral inequalities tailored to mappings within the aforementioned function class. Furthermore, we present an illustrative example featuring graphical representations and potential practical applications.
AnextensionofSchweitzer'sinequality toRiemann-Liouvillefractional integral
(OpenMathematics, 2024-08-26) LAKHDARI Abdelghani
ThisnotefocusesonestablishingafractionalversionakintotheSchweitzerinequality,specifically tailored to accommodate the left-sided Riemann-Liouville fractional integral operator. The Schweitzer inequalityisafundamentalmathematicalexpression,andextendingit tothefractionalrealmholdssignifi canceinadvancingourunderstandingandapplicationsoffractionalcalculus.
Application of Ant Colony Optimization for Job Shop Scheduling in the Pharmaceutical Industry
(Journal Européen des Systèmes Automatisés, 2023) LACHTAR Nadia; DRISS Imen (Co-Auteur)
Scheduling problems in the industrial sector are among the most studied optimization problems. Improving resource efficiency and minimizing production costs have become important concerns for industry managers. Seeking the best way to maximize profit is now a primary objective for any business. This is the context in which our study is positioned. It focuses on the resolution of job shop scheduling problems (JSSP). Considering that production challenges in industries are complex and require the consideration of multiple factors, we turn to the use of artificial intelligence tools for their resolution. Pharmaceutical manufacturing often involves a large number of resources, machines, and tasks, leading to high complexity in the JSSP. Ant colony optimization (ACO) is innovative and excels in its ability to handle this complexity by seeking optimal solutions while avoiding computational pitfalls. It can efficiently explore vast search spaces and leverage ant parallelism to reach the best solution in a short period of time, which is crucial in the pharmaceutical context where deadlines and quality constraints are paramount. Thus, in order to address the JSSP, this work suggests and puts into practice a method that involves the application of an ACO approach with the goal of minimizing the makespan. We validated our approach by comparing it with various algorithms through benchmarks taken from the published research. The suggested approach proved to be effective as the produced solutions were of high quality and showed that it could achieve results that are closer to the ideal solution for larger-scale issues than other algorithms with an average percentage relative error of just 0.67%. Furthermore, application of ACO in the context of BIOCARE's pharmaceutical laboratories’ production led to an improvement of approximately 3 hours in their weekly planning.
BACKLASH FAULT SUPPRESSION USING LQ OPTIMAL CONTROL BASED RST CONTROLLERS IN WIND TURBINE SYSTEMS USING BOND GRAPHS AND MATLAB/SIMULINK
(acta mechanica et automatica, 2021) BOUCHAREB Faouzi (Co-Auteur)
The presence of backlash in wind turbines is a source of limitations as it introduces nonlinearities that reduce their efficiency in speed/torque control which affect the performance of the power quality. Because of production tolerances during rotation, the teeth contact is lost for a small angle; until it is re-established, it produces a backlash phenomenon. The desire to eliminate this phenomenon is often hard to realise due to the nonlinear dynamic behaviour, which arises with the presence of backlash fault in a system. Therefore, the goal of this study is to develop an LQ optimal control structure in a form of an R-S-T controller in order to reduce the disturbing torque transmitted inside the dead zone of a gearbox in the wind turbine system. The actual system is also developed to be used as a demonstration model at lectures or presentations. The efficacy of the proposed control is illustrated via simulations

Browse

Browsing Publications Scientifiques et Pédagogiques by Title

Results Per Page

Sort Options