Institutional repository of university M'Hamed Bougara Boumerdes
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Living donors kidney transplantation and oxidative stress: Nitric oxide as a predictive marker of graft function
No full textBackground Glomerular filtration rate is the best indicator of renal function and a predictor of graft and patient survival after kidney transplantation. Methods In a single-centre prospective analysis, we assessed the predictive performances of 4 oxidative stress biomarkers in estimating graft function at 6 months and 1 year after kidney transplantation from living donors. Blood samples were achieved on days (D-1, D1, D2, D3, D6 and D8), months (M1, M3 and M6) and after one year (1Y). For donors, a blood sample was collected on D-1. Malondialdehyde (MDA), nitric oxide (NO), glutathione s-transferase (GST), myeloperoxydase (MPO), and creatinine (Cr) were measured by spectrophotometric essays. The estimated glomerular filtration rate by the modification of diet in renal disease equation (MDRD-eGFR) was used to assess renal function in 32 consecutive donor-recipient pairs. Pearson’s and Spearman’s correlations have been applied to filter out variables and covariables that can be used to build predictive models of graft function at six months and one year. The predictive performances of NO and MPO were tested by multivariable stepwise linear regression to estimate glomerular filtration rate at six months. Results Three models with the highest coefficients of determination stand out, combining the two variables nitric oxide at day 6 and an MDRD-eGFR variable at day 6 or MDRD-eGFR at day 21 or MDRD-eGFR at 3 months, associated for the first two models or not for the third model with donor age as a covariable (P = 0.000, r2 = 0.599, r2adj = 0.549; P = 0.000, r2 = 0.548, r2adj = 0.497; P = 0.000, r2 = 0.553, r2adj = 0.517 respectively). Conclusion Quantification of nitric oxide at day six could be useful in predicting graft function at six months in association with donor age and the estimated glomerular filtration rate in recipient at day 6, day 21 and 3 months after transplantation
Quadcopter stabilization using PID controller
No full text37 pDuring the last decade, quadcopter have been extensively used for many applications. A quadcopter is an under-actuated system because it uses four actuators to control six degrees of freedom, it is also considered as highly coupled and nonlinear system. Therefore, the design of a controller for the stabilization of the quadcopter during vertical flight represents a real challenge. The purpose of this work is to design and practically implement Proportional-Derivative-Integral (PID) control techniques, in order to control a quadcopter during vertical flight .I naddition ,w einvestigat eth eeffe ct ofP IDparamet ertuni ngon stability performance of the quadcopter system and the practical constraints encountered at differen tstage so fth ehardware/softwar eimplementatio nproces so fth equadcopter system, and propose suitable solutions. In this work, an ESP32 microcontroller was used as the main control unit. In addition, the MPU6050 Inertial Measurement Unit (IMU) was used to estimate the tilt angles of the quadcopter. Three PID controllers have been designed for each tilt axis, to maintain the quadcopter leveled during vertical flight
Design and implementation of an oven temperature controller using labview
No full text66 p.In this project, a closed loop temperature control system of an oven plant is designed and implemented including a digital computer, a data acquisition board together with a combination of hardware interfacing circuits and implementing a digital controlling algorithm.
The temperature of the oven is measured using the RTD sensor and a signal conditioning circuit.
This temperature feedback measurement from the plant is provided to the digital controller for calculating the required output to control the plant actuator (heating element).
The temperature digital controller is requested to have the best performances in response to disturbances as step input temperature reference changes and also to step load changes. In the case of accurate oven temperature-controlled application, the performance of the controller does not tolerate output overshoot and a reduced settling time is needed for optimizing production and hence affects the oven property of production efficiency.
Different tuning methods for the PID controller are explored, and their results are also presented. In addition to the PID controller, alternative control methods are proposed for improving the performance and reducing the overshoot in a first-order plus dead time temperature system. These alternative controllers include the Smith Predictor.
This project provides valuable insights into the development and design of a feedback control system. The system ensures that the oven temperature remains stable at a predefined set point. It comprises a data acquisition unit that facilitates communication between the PC, the sensor conditioning circuit, and the power triac circuit, that control the amount of power delivered to the oven
Optimisation du balayage et de la mobilité en réservoir mature : stratégie «Foam-Assisted-WAG» dans le Champ «GSE»
No full text80 p. : ill. ; 30 cmLes Réservoirs matures présentent des défis majeurs pour maximiser les taux de récupération finaux des hydrocarbures. Après avoir épuisé les méthodes de récupération primaire et secondaire, des techniques de récupération tertiaire ou assistée doivent être mises en œuvre. Parmi celles-ci, l'injection alternée de mousse, de gaz et d'eau (Foam-Assisted-WAG) est une approche prometteuse pour améliorer le balayage du réservoir et la mobilité des fluides. Cette thèse porte sur l'évaluation technico-économique détaillée d'un projet «Foam-Assisted -WAG » pour le champ pétrolier mature GSE. Dans un premier temps, différents scénarios d'injection alternée de gaz et d'eau (WAG) conventionnels ont été étudiés afin d'identifier le schéma optimal. Malgré des gains de récupération, les simulations ont révélé des limitations persistantes, notamment une remontée rapide du GOR, des baisses de pression défavorables et un taux de récupération final limité. Pour remédier à ces problèmes, l'injection de mousse a été intégrée au schéma WAG optimal. Le tensioactif AOS a été sélectionné pour générer une mousse stable à haute température, offrant un excellent contrôle de la mobilité du gaz
تحسين الأداء المالي على مستوى الجماعات الإقليمية كرهان لتخفيف أعباء الدولة : دراسة حالة
No full text218 ص. ، 30 سمتحسين الأداء المالي للجماعات الإقليمية هو عملية هامة لتوفير الموارد المالية من اجل تحقيق الاكتفاء المالي الذاتي لها، وتوفير الخدمات العامة المجانية للمواطنين ذات الجودة العالية ولا يتم تحسين الأداء المالي الا باتخاذ إجراءات وسياسات مالية فعالة وتنفيذ مجموعة من الاستراتيجيات والخطط المالية، مع استخدام مجموعة من المؤشرات المالية بغرض قياس الأداء المالي وتقييمه وفي الأخير تحسينه.
وهدفت الدراسة لمعرفة أثر العوامل الداخلية والخارجية على تحسين الأداء المالي في الجماعات الإقليمية بولاية البويرة، باستهداف عينة مقدرة بـــ 65 مفردة من الموظفين موزعين على بلديات ولاية البويرة، والذي تم توزيع استبيان عليهم يتكون من 71 عبارة، حيث تم الاعتماد على المنهج الوصفي التحليلي في الدراسة، كما اعتمدت الدراسة على برنامجSPSS لمعالجة وتحليل البيانات ولاستخدام الاختبارات الوصفية والاختبارات المتعلقة بفرضيات الدراسة.
وتوصلت نتائج الدراسة في الجانب الوصفي إلى وجود مستوى عالي في استخدام تكنولوجيا المعلومات والتحكم بالمحاسبة العمومية ووجود مستوى متوسط في تطبيق القوانين والتشريعات وأداء المورد البشري مع وجود مستوى عالي للعوامل الداخلية المؤثرة على الأداء المالي في الجماعات الإقليمية بولاية البويرة، ووجود مستوى متوسط في الرقابة المالية للجماعات والاستثمار المحلي وتثمين الممتلكات مع وجود مستوى متوسط للعوامل الخارجية المؤثرة على الأداء المالي في الجماعات الإقليمية بولاية البويرة، ووجود مستوى عالي في إعداد تقارير الأداء المالي ووجود مستوى متوسط في إعداد ميزانية ومؤشرات الأداء المالي وتقييم وقياس الأداء المالي والإيرادات والنفقات مع وجود مستوى متوسط في الأداء المالي في الجماعات الإقليمية بولاية البويرة.
وتوصلت النتائج في الشق المتعلق باختبارات الفرضيات إلى وجود أثر للعوامل الداخلية والخارجية على مؤشرات الأداء المالي وعلى إعداد تقارير الأداء المالي وعلى ميزانية الجماعات الإقليمية والخطط والبرامج بولاية البويرة، وعدم وجود أثر للعوامل الداخلية والخارجية على الإيرادات والنفقات وعلى تقييم وقياس الأداء المالي في الجماعات الإقليمية بولاية البويرة، وبشكل عام يوجد أثر للعوامل الداخلية والخارجية على تحسين الأداء المالي في الجماعات الإقليمية بولاية البويرة.
كما اوصت الدراسة بمجموعة من التوصيات من اجل تحسين الأداء المالي بالجماعات الإقليمية لولاية البويرة، ومن أهمها تطوير الخطط الاستراتيجية والمالية وتنويع مصادر الإيرادات والتقليل من النفقات، وضرورة تعديل القوانين والتشريعات الخاصة بالجماعات الإقليمية ووضع قوانين خاصة بتقييم وقياس الأداء المالي لها، كما اوصينا بضرورة الاهتمام بالمورد البشري من خلال الحوافز والمكافآت وتدريبه على استخدام تكنولوجيا الاعلام والاتصا
Design of an Advanced Optimal Fuzzy Controller For a Binary Distillation Column
No full textThe most common control philosophy followed in the chemical process industries is the SISO system using the conventional PID controller algorithms. One drawback is relying on models for both control and design work in Chemical process industries (CPI) is that many problems are very complex and accurate models are difficult, if not impossible to obtain. To overcome these problems, it will be helpful to apply techniques that use human judgment and experience rather than precise mathematical models, which in the major cases deduced from the linearization of the system and simplification hypothesis. The fuzzy logic systems are capable of handling complex, nonlinear systems using simple solutions. However, obtaining an optimal set of fuzzy membership functions is not an easy task. In this chapter a solution based on artificial intelligence is proposed to improve the control of a binary distillation column. The solution is based on the use of the advantages of both fuzzy logic and genetic algorithms. The fuzzy logic is used as a supervisory PI controller that is a simple PI controller that generally used in controlling distillation columns with parameters deduced from the fuzzy supervisor. The membership functions shape is deduced by using research algorithms based on hierarchical genetic algorithms. The results show that the Fuzzy supervisory PI controller provide an excellent tracking toward set point chang
Multi-objective optimization of series-parallel system with mixed subsystems failure dependencies using NSGA-II and MOHH
No full textIn complex systems, failure dependencies play a crucial role in determining their overall performance. This paper explores the multi-objective optimization of series-parallel systems with mixed failure dependencies. By optimizing system cost and availability, the study aims to identify the most efficient redundancy and repair strategies. Two optimization algorithms, the non-dominated sorting genetic algorithm II (NSGA-II) and a novel multi-objective algorithm named the multi-objective hoopoe heuristic (MOHH), are utilized alongside constraint handling techniques to produce Pareto fronts. These fronts illustrate the trade-offs between cost and availability. Additionally, a fuzzy decision method is utilized to determine the best compromise solutions from each optimization technique. Comparing the results, NSGA-II consistently outperforms MOHH in providing better compromise solutions across five independent runs. However, MOHH demonstrates a better standard deviation in its performance
Contribution to chaotic encryption methods for digital data
No full text107 p. : ill. ; 30 cmIn this thesis, we investigate the development process of chaos-based image encryption algorithms from various perspectives, including the serious challenge of generating secure random number sequences for use as dynamic encryption keys. First, at the aim of improving the randomness and non-periodicity qualities of the basic pseudo-random number generators (PRNG) used as key-stream generators, we exploit the unique attributes of the logistic map (LM), logistic-sine system(LSS), linear feedback shift registers (LFSR), and nonlinear feedback shift register (NLFSR) to design new key-stream generators (namely: LSS-LFSR-PRNG, LM-NLFSR-PRNG, and LSS-NLFSR-PRNG). Therefore, our generators succeed in generating unlimited, random, and nonlinear sequences by passing the totality of the National Institute of Standard and Technology (NIST) statistical tests, and displayed strong cryptographic security, resulting in high entropy, high key sensitivity, and large key space exceeding 2^100.
The second goal highlights the importance of selecting an appropriate chaos-based architecture for confusion and diffusion. The dimensions of the chaos-based confusion-diffusion architecture vary depending on the specific chaotic map being used. Hence, we design three confusion-diffusion algorithms of various levels (1D LM-based cryptosystem, 1D LM-Chebyshev-based cryptosystem, and 3D intertwining logistic map-cosine (ILM) based cryptosystem), to discuss and demonstrate the impact of choosing the appropriate dimension of the chaotic map on the vulnerability of a cryptosystem. It has been proven that higher-dimensional chaotic maps, such as 3D-ILM, can enhance the ability to resist exhaustive and statistical attacks by achieving desirable values of the number of pixels change rate (NPCR) and unified average changing intensity (UACI), while these maps are unable to maintain encryption speed.
The third goal of this thesis is to improve the core of the mathematical model of chaos-based cryptosystems by boosting the chaotic complexity and chaotic range of basic one-dimensional chaotic maps. Where, we propose a new nonlinear chaotification system capable of producing 1D enhanced discrete chaotic maps (enhanced tangent-Logistic map T-LM, enhanced tangent-Sine map T-SM, and enhanced tangent-Chebyshev system T-CH), by applying tangent nonlinear transforms to the outputs of the existing chaotic maps. This strategy improves the performance of basic 1D chaotic maps by exhibiting better dynamical behavior, Lyapunov exponent, bifurcation, and larger chaotic interval
مطبوعة دروس في القانون الدستوري
No full textإن دراسة وتحليل أي نظام سياسي لدولة ما بصفة شاملة، يقتضي مناقشة وبحث الخصائص
العامة لهذا النظام السياسي الذي يتطلب التعرض للتطور السياسي الذي مر به قبل وصوله للشكل
الذي يأخذه حاليا، هذا من جهة، ومن جهة أخرى دراسة المؤسسات الدستورية " السلطات السياسية"
لمعرفة شكل الحكم، وكيفية تنظيمها في الدولة واختصاصاتها ومدى العالقة فيما بينهما .
اجتهد الفقه ومنذ القديم في تصنيف وإعطاء مفهوم للنظم السياسية، حيث يقصد بها
دراسة نظم الحكم في الجماعات السياسية المختلفة، أي دراسة األشكال المختلفة لممارسة السلطة
السياسية، مما يعني أن دراسة النظام السياسي لدولة معينة هو دراسة طريقة ممارسة السلطة السياسية
التي ينظمها القانون األعلى لها
Modélisation et conception d’un réseau de collecte de champ Nord In Amenas huile du projet de «Tinrhert»
No full text87 p. : ill. ; 30 cmCe Projet de fin d'études a pour objectif d'analyser en détail la faisabilité du raccordement de quatre puits producteurs d'huile au centre de traitement d'huile d'Alrar Initialement, ces puits étaient connectés au centre de traitement d'In Amenas. Cependant, en raison de la capacité insuffisante de ce centre, il a été décidé de rétablir le raccordement vers Alrar. Nous utilisons Pipesim pour modéliser le système de production. Ensuite, nous effectuons divers scénarios de simulation pour prévoir et évaluer les performances du système, tout en prenant en compte les aspects techniques et économiques