Institutional repository of university M'Hamed Bougara Boumerdes
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Mise En Place d'une Solution de Sécurité Réseau à Base de Fortigate et Nagios
No full text89 p. : ill. ; 30 cmDans le cadre de notre projet, nous avons étudié les concepts fondamentaux de la sécurité informatique. Nous avons déployé le pare-feu “FortiGate”, qui offre une multitude de fonctionnalités. Ensuite, nous avons configuré le filtrage du trafic du réseau local (LAN) et installé un serveur Nagios pour superviser et administrer notre réseau. Cette approche proactive nous permet de détecter rapidement toute activité suspecte et de prendre des mesures pour renforcer la sécurité
Relationship between structural and mechanical properties of polyethylene matrix nanocomposites
No full textThis study examined the impact of incorporating graphene nanoplatelets (GnP) into high-density polyethylene (PE) to create nanocomposites, with and without a compatibiliser. We specifically focused on the impact of structural crystallinity on the mechanical properties of the nanocomposites. These nanocomposites exhibited a much higher Young's modulus compared with pure PE. Specifically, the Young’s modulus increased exponentially with the addition of a compatibiliser and linearly without it. One explanation for this exponential rise in Young's modulus is that the crystal's compacted polymer chain structure improved its stiffness, facilitating effective load transfer. Additionally, a poor distribution of GnP in the nanocomposites with a filler content of 0.5 and 1 wt.%, both with and without a compatibiliser, led to a decreased stress and strain at break. However, at higher filler contents, well-distributed GnP play a key role in enhancing stress and strain at break
Modélisation d’un turbogénérateur commandé par un régulateur automatique de tension «AVR»
No full text88 p. : ill. ; 30 cmCe Mémoire se concentre sur l’étude et la modélisation des turbines à vapeur et des alternateurs, avec un accent particulier sur la régulation de la vitesse de rotation et la tension de sortie du générateur par un régulateur automatique de tension (AVR). Ce mémoire offre une analyse approfondie des turbines à vapeur et des alternateurs, et fournit des informations précieuses sur la régulation de la vitesse de rotation et de la tension de sortie du générateur par l’AVR. Il sert de ressource précieuse pour ceux qui s’intéressent à l’étude et à la modélisation des turbines à vapeur et des alternateurs
Chemical composition, antimicrobial and antioxidant activities of methanolic extracts of the Algerian Artemisia campestris L. at different stage of growth
No full textArtemisia campestris, widely abundant in North Africa, is usually used as a decoction to treat several diseases; but its chemical composition at different growth stages and along a climatic gradient has never been investigated. In this study, phytochemical content, antioxidant and antimicrobial activities of crude methanolic fractions from dry aerial parts of A. campestris, growing in two different bioclimatic conditions, were compared. The growth stages, vegetative and reproductive, were also taken into consideration. The HPLC analysis revealed the presence of several compounds like ascorbic, isovannilic, ferrulic and cinnapic acids. The antioxidant activity was evaluated with two different methods: DPPH and FRAP essay. The four samples showed very high antioxidant activity. The in vitro antimicrobial activity shows a strong inhibitory effect against gram positive bacteria. But, they were resistant to gram negative bacteria and yeast. The biggest inhibition diameter was recorded against S. aureus and B. cereus
Optimization of the activity of Mo7-Zn3/CaO catalyst in the transesterification of waste cooking oil into sustainable biodiesel via response surface methodology
No full textAn enriched basic site CaO-supported bimetallic Molybdenum-Zinc (Mo7-Zn3) catalyst was successfully synthe-
sized via wet-impregnation and evaluated for the transesterification of waste cooking oil into biodiesel. The
physicochemical characterization of the Mo7-Zn3/CaO catalyst demonstrated good dispersion of CaMoO4 and
ZnO oxides on CaO support, with a mesoporous structure allowing for better mass transfer between reactants.
The Mo7-Zn3/CaO catalyst exhibited high transesterification activity (95 ± 0.3 % FAME conversion), owing to
the large density of strong Brønsted basic sites (conjugated O2–) generated from simultaneous interaction among
Ca2+, Zn2+, and Mo6+ metal species. Response Surface Methodology (RSM) and Box Behnken Design (BBD) were
used to optimize the reaction and indeed, the utmost FAME conversion of 95 % is achieved using 3.37 wt%
catalyst loading, 12:1 methanol to oil molar ratio within 2.27 h at 62.7 ◦C reaction temperature. The model
reliability in predicting the FAME yield using the established catalyst under varying operational conditions was
excitedly validated with a reasonable accuracy error of 0.5 %. The catalyst exhibited good stability, maintaining
a high FAME conversion (95–85 %) during 5 reusable cycles without significant loss in catalytic activity. A closer
look for a detailed approach and a heterogeneous mechanism for the reaction using Mo7-Zn3/CaO catalyst was
proposed. The physical and chemical properties of the produced biodiesel were carefully compared with the
standard for biodiesel, and were found to majorly comply with ASTM D6751 and EN 14214 biodiesel properties.
An investigation into the economic competitiveness and industrial applicability of biodiesel production using
Mo7-Zn3/CaO from WCO reveals significant potential for sustainable and efficient biodiesel synth
Wind Turbine Mechanical Speed Regulation Reliability Of Artificial Intelligent PSO-FLC Control
No full textthis paper addresses modeling and control of a wind energy conversion system (WECS). The WECS based on Permanent Magnet Synchronous Generator, PMSG. Wind energy transformed to mechanical energy via blade and turbine to give speed and torque to the PMSG. This mechanical speed will be controlled firstly with a classical MPPT-PI then will be optimized by a PSO algorithm, after that a new intelligent controller MPPT-FLC will be applied to show the efficiency of that's kind of controller on our WECS mechanical speed control. The analysis and discussion of the simulation results aim to enhance the reliability and efficiency of each suggested approach. Keywords - Wind turbine, Speed control, Optimization, FLC, PSO, PI
Polycopié de cours de (Méthodes de Biologie Moléculaire) : Ce polycopié est destiné aux étudiants inscrits en Licence L3 Spécialité : Biologie Moléculaire
No full textUsing Machine Learning Algorithms for the Analysis and Modeling of the Rheological Properties of Algerian Crude Oils
No full textOur research described in this report investigated the rheological behavior of crude oils from the Tin Fouye Tabankort oil field in Southern Algeria, focusing on their viscosity under varying temperatures (10 °C–50 °C). The results show that the oils exhibited non-Newtonian shear-thinning behavior at low shear rates, with the viscosity decreasing as the temperature was increased. At higher shear rates, the Herschel–Bulkley model accurately described the oils’ transition to Newtonian behavior. Machine learning models, including CatBoost, LightGBM, and XGBoost, were trained on the experimental data to predict the viscosity, with CatBoost and XGBoost showing superior performance. We suggest these findings are valuable for improving the efficiency of oil transportation and processing
High-Quality Synthesized Face Sketch Using Generative Reference Prior
No full textFace sketch synthesis (FSS) is considered as an image-to-image translation problem, where a face sketch is generated from an
input face photo. FSS plays a vital role in video/image surveillance-based law enforcement. In this paper, motivated by the recent success of
generative adversarial networks (GAN), we consider conditional GAN (cGAN) to approach the problem of face sketch synthesis. However,
despite the powerful cGAN model’s ability to generate fine textures, low-quality inputs characterized by the facial sketches drawn by artists
cannot offer realistic and faithful details and have unknown degradation due to the drawing process, while high-quality references are inacces-
sible or even unexistent. In this context, we propose an approach based on Generative Reference Prior (GRP) to improve the synthesized face
sketch perception. Our proposed model, that we call cGAN-GRP, leverages diverse and rich priors encapsulated in a pre-trained face GAN
for generating high-quality facial sketch synthesis. Extensive experiments on publicly available face databases using facial sketch recognition
rate and image quality assessment metrics as criteria demonstrate the effectiveness of our proposed model compared to several state-of-the-art
methods
