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Dynamic Resource Allocation for 5G Network Slices Using a Hybrid DRL–GA Approach
(2026) REGHAOUAT Douaa El Aldja; DAHMANI Maroua; BENZERBADJ A
Dynamic resource allocation between co-existing network slices is one of the most chal- lenging problems in 5G Radio Access Network management. In a Vehicle-to-Everything (V2X) highway scenario, a URLLC slice serving safety-critical collision-avoidance messages and an eMBB slice serving high-definition cameras and passenger internet access must share a fixed 100 MHz radio pool under non-stationary, multi-regime traffic conditions. Satis- fying the strict latency constraint of the URLLC slice and the load-dependent bandwidth requirement of the eMBB slice simultaneously, at every one second decision epoch, is an NP-hard problem that classical and standalone intelligent methods cannot fully resolve. This thesis proposes a Hybrid Deep Q-Network + Adaptive Genetic Algo- rithm (Hybrid DQN+GA) framework that addresses three structural limitations iden- tified in the state of the art: the discrete action ceiling of DQN-based agents, the cold- start inefficiency of standalone Genetic Algorithms, and the absence of a bidirectional co-adaptation loop between learning and evolutionary search. At every decision epoch, the DQN provides a fast, experience-driven, discrete allocation seed; the Adaptive GA re- finer searches the continuous bandwidth interval when a constraint violation is detected, using a multi-directional warm-start strategy seeded from the DQN output and domain- knowledge candidates; and the resulting refined allocation is fed back to train the DQN, forming a self-improving co-adaptation loop. The framework is evaluated in a simulated environment with five traffic regimes Nor- mal, Rush-hour, Accident, Peak-eMBB, and Night over 500 training episodes and 100 greedy evaluation episodes, against a Static Allocation baseline and a standalone DQN. The Hybrid agent achieves an overall QoS satisfaction of 75.34% (vs. 74.10% for DQN and 65.96% for Static), an eMBB satisfaction of 53.49% (+11.0% over DQN), a per-step violation rate of 0.493 (−4.8% over DQN), and a mean reward of 7.51. During safety- critical accident events, the Hybrid agent allocates 69 MHz to the URLLC slice 19 MHz more than the DQN— maintaining a latency of 4.8 ms under near-maximum load. All decisions are produced with a computational overhead below 1 ms per epoch, confirm- ing practical deployability on a Mobile Edge Computing server co-located with the base station.
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Contribution à l’étude des souches de bactéries lactiques isolées à partir du lait de chèvre
(2026) Boudissa Ainouna Mounia; Abdelhakem Khouloud; Daghbadje Warda; BELLAHCENE Mouloud
This study focused on the isolation and characterization of lactic acid bacteria from raw goat milk collected in the Ain Témouchent region. The experimental work involved physicochemical analyses, including the measurement of pH and titratable acidity. Several microbiological analyses were also carried out to investigate the presence of total flora, coliforms, staphylococci, yeasts and molds, as well as lactic acid bacteria in goat milk samples. After isolation and purification, the obtained isolates were subjected to various identification tests, including Gram staining, catalase and oxidase tests, growth at different temperatures, pH levels, and NaCl concentrations, determination of the fermentative type, thermoresistance testing, and growth on Sherman milk-based medium. The antagonistic activity of the isolates against three pathogenic microorganisms was also evaluated, and an antibiotic susceptibility test was performed. The results revealed the presence of Gram-positive and catalase-negative lactic acid bacteria, showing good adaptation to various growth conditions and inhibitory activity against certain pathogenic microorganisms. This study therefore confirms the importance of raw goat milk as a source of lactic acid bacteria that can be exploited in the agri-food and biotechnological fields.
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Finite Element Analysis of Crack and Scratch Defect Interaction in a Buried API X80 Pipeline
(2026) LAMRI SIDAHMED EL MAHDI; OUDAD WAHID
The structural integrity of oil and gas pipelines is strongly influenced by the presence of defects that may develop during manufacturing, installation, or service. Among these defects, cracks and scratches are considered critical because they create stress concentrations that can reduce the load-carrying capacity of the pipeline and increase the risk of failure. Understanding the interaction between such defects is therefore essential for ensuring safe and reliable pipeline operation. This work investigates the interaction between crack and scratch defects in a buried API 5L X80 steel pipeline using the Finite Element Method (FEM). Numerical simulations were performed with ABAQUS to analyze the influence of defect geometry, including crack depth, crack width, scratch depth, scratch width, and scratch orientation. The distributions of Von Mises stress, equivalent plastic strain (PEEQ), and J-integral were evaluated to characterize the mechanical and fracture behavior of the pipeline. The results show that increasing defect dimensions leads to higher stress concentration and plastic deformation levels. Furthermore, the J-integral values increase with crack size, indicating a greater tendency for crack propagation. The study also highlights the influence of repair configurations on reducing the crack driving force and improving structural integrity. The findings contribute to a better understanding of defect interaction mechanisms in high-strength pipeline steels and provide useful information for pipeline integrity assessment and maintenance strategies.
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Analyse expérimentale des émissions éléctromagnétique d’un variateur de vitesse commande par NE555
(2026) HAMEL OUM ELKHEIR; AMER BEN BEKRIT IKRAM; BENAZZA Baghdadi
This study presents an experimental analysis of electromagnetic interference (EMI) generated by a PWM speed controller for a DC motor, driven by an NE555 integrated circuit. The work focuses on designing the prototype and measuring the conducted emissions produced during the fast switching of power electronic components. The experimental results demonstrate that high voltage (dv/dt) and current (di/dt) variations are the primary sources of interference. Finally, the effectiveness of several mitigation techniques—including EMI filters, wiring optimization, and shielding—is validated to improve the system's electromagnetic compatibility (EMC).
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الحماية القانونية للألشخاص ذوي إلاعاقة في التشريع الجزائري
(Universite of ain Temouchent, 2025) بوري عتيقة; بن طاع الله زهيرة
This research addresses the topic of the legal protection of persons with disabilities in Algerian legislation, through a comprehensive study of conceptual and legislative aspects. It highlights the evolution of the social perception of people with disabilities—from marginalization to full recognition of their rights. The research focuses on the medical, social, and legal definitions of disability, the legal framework, and the effective mechanisms for protecting the rights of persons with disabilities. It examines various relevant Algerian laws, such as :Law 85-05 related to health , Law 09-02 for the protection of persons with disabilitie ,Law 22-10 concerning their promotion ,In addition to constitutional provisions, particularly Article 72 of the 2020 Constitution. The study also addresses their rights to education, health, employment, social participation, and protection from discrimination. It emphasizes the importance of enshrining equality and equal opportunities, the need to implement laws effectively on the ground, and to support their full integration into society .