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Rheological behavior and microstructural properties of crude oil and emulsions (water/oil-oil/water)
No full textAn experimental study on crude oil (from the Tin Fouye Tabankort oil field in southern Algeria) was carried out. This study allowed us to understand the rheological behavior of this crude oil with these different emulsions and how it reacts under the effects of temperature and the inversion of its phase from E/H to H/E. So we measured the rheological characteristics by tests flow and dynamic mode at different temperatures from 10 °C to 50 °C and at different water concentrations (20.40.50.60 and 70%) at a fixed temperature of 20 °C. The increase in temperature results in a 31.84% reduction in the initial viscosity of the crude oil. The addition of the volumic fractions of water results in an increase in viscosity at the point of inverse, which will decrease the apparent viscosity of these emulsions where the emulsions (W/O) come from (O/W). This crude oil and their emulsions exhibit a non-Newtonian behavior with shear thinning. The dynamic analysis depends on the temperature and the percentages of water added to the crude oil. At the end, a microscopic analysis was added to verify the relationship between the shape and diameter of the water droplets in each emulsion and the viscosity variation
Étude d’impact environnemental lies aux activités de forage pétrolier
No full text73 p. : ill. ; 30 cmCette Étude vise à minimiser les effets potentiels des opérations de forage sur les écosystèmes terrestres et aquatiques, ainsi que sur les communautés humaines avoisinantes. Elle examine les risques de contamination des sols et des eaux, les émissions de gaz à effet de serre, les perturbations de la faune et de la flore locales.
Ainsi, une identification des aspects et impacts environnementaux liés au projet a été établit afin de proposer des mesures préventives. Enfin, en parle sur les traitements de déblais de forage à cause de leurs toxicités et grande absorption des huiles
Contribution to improving the efficiency of a wireless power transfer system using artificial intelligence techniques
No full text104 p. : ill. ; 30 cmWireless Power Transfer (WPT) technology is an innovative method for powering devices without physical wires, which has been used here to provide power to bioimplantable devices. The main design constraints are to achieve maximum transfer efficiency while keeping the implant size small enough to be suitable for the living subject's body. Magnetic Resonant Coupling Wireless Power Transfer (MRCWPT), which uses pairs of inductor coils in the external and implant circuits, is a method actively researched for this type of power transmission.
The objective of this thesis is to design and optimize a high-efficiency WPT receiving coil for biomedical applications. Traditionally, optimizing WPT systems based on mathematical equations or numerical models is often time-consuming and may not yield optimal designs. To address these limitations, this thesis introduces a novel approach that integrates a machine-learning model with metaheuristic methods for design and optimization.
The primary goal is to maximize the transfer efficiency for an implantable coil with dimensions of 20 mm and a transfer distance of 30 mm, operating at a frequency of 13.56 MHz. To achieve this goal, we firstly identified the critical geometric coil parameters that significantly influence the WPT system's efficiency. A model-based Artificial Neural Network (ANN) was then constructed and trained on a comprehensive dataset generated through Finite Element Method (FEM) simulations. This model predicts efficiency based on geometric coil parameters, eliminating the need for complex calculations. Subsequently, two metaheuristic algorithms: the Genetic Algorithm (GA) and the Coyote Optimization Algorithm (COA), were employed to find the optimal parameters that maximize efficiency.
The proposed ANN model demonstrates exceptional accuracy, exceeding 97%. Furthermore, this WPT coil design approach significantly enhances transfer efficiency by up to 76% while drastically reducing computation time compared to conventional method
Klein-Gordon equation in higher dimensions via Feynman propagator with the modified second type Pöschl-Teller potential
No full textRecently, the Feynman approach has been used to study the solution of the D-dimensional Klein-Gordon equation under equal scalar and vector modified second type Pöschl-Teller potentials. Approximation has been made to the centrifugal term and space-time transformation is used to deal easily with the difficult computation problem. We found that there are positive energy states for bound states based on the condition for the wave functions. The results are in agreement with those obtained by using other methods found in the literature
Renforcement de la sécurité du réseau de la Direction Générale NESDA via FireWall
No full text83 p. : ill. ; 30 cmLa sécurité informatique consiste à protéger les actifs informatiques d’une organisation, tels que les systèmes, les réseaux, les appareils numériques et les données, contre les accès non autorisés, les violations de données et les cyberattaques1. Elle englobe des mesures telles que la sécurité des terminaux, du cloud, du réseau et des applications. Les coûts des violations de données peuvent être considérables, affectant le chiffre d’affaires, la réputation et entraînant des amendes et des pertes d’actifs.C'est dans ce contexte que nous avons entreprise le développement de notre propre solution, spécifiquement adaptée aux besoins de l’entreprise. Ce projet se distingue par une approche optimisée, économique et précise, permettant de renforcer la sécurité d'entreprise et optimiser d'une maniére générale les performances de résea
Compensation de l'énergie réactive à l'aide d'un «SVC»
No full text64 p. : ill. ; 30 cmLa Stabilité des réseaux électriques est une question très importante dans la planification et l'exploitation de ces réseaux. Parmi les indicateurs de qualité de l'énergie électrique, nous citons le niveau de tension et l'ordre des pertes qui sont considéré comme les deux principales préoccupations importantes des gestionnaires des réseaux électriques. Pour cela, ce travail se concentre sur amélioration de la stabilité de la tension statique ainsi que la réduction des pertes, en prenant en compte systèmes flexibles â courant alternatif (FACTS) et plus particulièrement les compensateurs statiques de puissance réactive (SVC)
A New Facial Expression Recognition Algorithm Based on DWT Feature Extraction and Selection
No full textIn this paper, we propose an efficient framework to improve accuracy and computational cost of a Facial Expression Recognition (FER) system. This framework is carried out in three stages. In the initial one, corresponding to feature extraction, three descriptors, derived from Discrete Wavelet Transform (DWT), are introduced to extract distinct feature types. In the second stage, focused on feature selection, a Wrapper approach is adopted to carefully select the most relevant features from the previously extracted pool. Following feature selection, the Support Vector Machine (SVM) classifier is employed, in the final stage, to determine an individual's affective state. The experiments were conducted in person-independent mode using both the Japanese Female Facial Expression (JAFFE) and extended Cohn-Kanade (CK+) databases which included the following emotions: anger, disgust, contempt, fear, happy, sad, surprise, and neutral. The obtained results demonstrated the effectiveness of the proposed framework in increasing recognition rate and decreasing response time compared to other state-of-the-art methods. A comparative study between our proposed framework and that based on the Local Binary Patterns (LBP) method demonstrated that our framework outperforms the latter for most emotions. In fact, our proposed framework converges rapidly and achieves good performance, thus allowing us to develop a real-time Facial Expression Recognition (FER) system in person-independent mode. Average recognition rates of 89.66% and 87.76% were obtained using our method with the JAFFE database and the CK+ database, respectively
دراسة كمية لتحليل الأثار الديناميكية لصدمات السياسة المالية : دراسة حالة الجزائر 1970ــ 2017
No full text255 ص. ، 30 سمتهدف هذه الدراسة إلى محاولة التحقق من الأثار الديناميكية لصدمات السياسة المالية في الجزائر وأثرها على مستوى النشاط الاقتصادي ممثلا في تقلبات الناتج المحلي الحقيقي والاستهلاك النهائي للأسر، واعتمدنا لأجل ذلك على بيانات سنوية تغطي الفترة من 1970 إلى غاية 2017، وقد قمنا باستخدام مقاربة نموذج متجه الانحدار الذاتي الهيكلي، يحتوي على متغيرات النفقات العامة، الإيرادات العامة والناتج المحلي الإجمالي، في إطار أربعة استراتيجيات مختلفة لتحديد القيود الهيكلية المعبرة عن التأثيرات الآنية، بغية تأكيد أو نفي حساسية النتائج لشكل القيود داخل نموذج (SVAR) المقترح.
أظهرت نتائج الدراسة أن مختلف التقديرات التي أنجزت إلى جانب دوال الاستجابة الدفعية المقدرة لكل استراتيجية على حدى وجود تباين طفيف بين بعضها البعض، يجعلنا نميل إلى حقيقة عدم حساسية النتائج المستخرجة لشكل النموذج المستعمل أو لشكل القيود المفروضة داخل نموذج (SVAR)، كما تم التوصل إلى أن صيغة النموذج الموسع مع تحديد للقيود الهيكلية في إطار مخرجات النظرية الاقتصادية وما تقره للعلاقة الموجودة بين تغيرات الانفاق العام والايرادات الكلية مع الناتج المحلي، هي أحسن صيغة يمكن من خلالها وصف وتحليل أثر السياسة المالية على الناتج المحلي في الجزائ
Basic Red 46 adsorption studies onto pyrolyzed by-product biomass
No full textIn this study, the objective was to examine the utilization of the pyrolyzed by-products biomass as an adsorbent for extract-
ing the dye Basic Red 46 (BR 46) from a solution. The pyrolyzed by-product containing Pleurotus mutilus biomass was
characterized by thermogravimetric analysis (TGA), FTIR and μXRF. Different parameters effects such as, adsorbent dose,
solution pH, contact time, temperature and initial dye concentration on the adsorption capacity of the pyrolyzed by-product
biomass were examined. The solution was analyzed before and after the adsorption studies. With adsorbent dose of 1 g/L,
contact time of 14 min, and solution pH of 7.5, the optimum yield of 88% was achieved. In order to fit the equilibrium data,
the Langmuir, Freundlich, Temkin, and Khan isotherm models were used, and in order to fit the kinetics data, the pseudo-
first-order, pseudo-second-order, Elovich, and Ritchie models were employed. Statistical analysis such as R2 , RMSE,2 and
ARE was used to assess which model has the best fit with the experimental data. The results demonstrated that the experi-
mental equilibrium data are well described by the Langmuir model, and the kinetic studies indicated that the adsorption of
BR46 followed the Ritchie model. The greatest BR 46 adsorption capacity determined from experimental equilibrium data
was around 135 mg/g at pH = 7.5, adsorbent dosage of 1 g/L. Moreover, thermodynamic analysis has demonstrated that the
adsorption process was physical, exothermic, and spontaneous in nature. These results indicated that pyrolyzed by-product
biomass might be used as a cheap material to extract textile colors out of aqueous effluents
Predicting genetic risk factors for AA amyloidosis in Algerian patients with familial Mediterranean fever
No full textRenal amyloid-associated (AA) amyloidosis is a harmful complication of familial Mediterranean fever (FMF). Its occurrence involves polymorphisms and mutations in the Serum Amyloid A1 (SAA1) and Mediterranean Fever (MEFV) genes, respectively. In Algeria, the association between SAA1 variants and FMF-related amyloidosis was not investigated, hence the aim of this case-control study. It included 60 healthy controls and 60 unrelated FMF patients (39 with amyloidosis, and 21 without amyloidosis). All were genotyped for the SAA1 alleles (SAA1.1, SAA1.5, and SAA1.3), and a subset of them for the − 13 C/T polymorphism by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Comparisons between genotype and allele frequencies were performed using Chi-square and Fisher tests. The SAA1.1/1.1 genotype was predominant in amyloid FMF patients, compared to non-amyloid FMF patients (p = 0.001) and controls (p < 0.0001). SAA1.1/1.5 was higher in non-amyloid patients (p = 0.0069) and in controls (p = 0.0082) than in patients with amyloidosis. Bivariate logistic regression revealed an increased risk of AA amyloidosis with three genotypes, SAA1.1/1.1 [odds ratio 7.589 (OR); 95% confidence interval (CI): 2.130-27.041] (p = 0.0018), SAA1.1/1.3 [OR 5.700; 95% CI: 1.435–22.644] (p = 0.0134), and M694I/M694I [OR 4.6; 95% CI: 1.400-15.117] (p = 0.0119). The SAA1.1/1.5 genotype [OR 0.152; 95% CI: 0.040–0.587] (p = 0.0062) was protective against amyloidosis. In all groups, the − 13 C/C genotype predominated, and was not related to renal complication [OR 0.88; 95% CI: 0.07–10.43] (p = 0.915). In conclusion, in contrast to the − 13 C/T polymorphism, the SAA1.1/1.1, SAA1.1/1.3 and M694I/M694I genotypes may increase the risk of developing renal AA amyloidosis in the Algerian population