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Comparison between PI-DTC-SPWM and fuzzy logic for a sensorless asynchronous motor drive

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Protection and Control of Modern Power Systems 2021年第1期6卷 430-442页

作者： Soukaina El Daoudi loubna Lazrak Laboratory of Automatic Energy Conversion and MicroelectronicsFaculty of Sciences and TechnologySultan Moulay Slimane UniversityBeni MellalMorocco

Currently, asynchronous cage motors are among the most commonly requested machines accentuated by their extension to the field of electric vehicles. Therefore, the development of robust and sophisticated controls for this machine is of significant interest. Artificial intelligence control techniques, such as fuzzy logic, are at the forefront of recent research. However, their design becomes much more complicated for a motor via a multilevel inverter. The main purpose of this paper is to show that it is possible to achieve fuzzy logic control of a squirrel cage asynchronous motor supplied via the usual two-level inverter. This is achieved, by adopting a DTC strategy based on a sinusoidal PWM with multilevel inverter. It employs a feedback information estimator with dual structure between the sliding mode observer at low speed and the model reference adaptive system in sliding mode at high speed. For both installations, speed is regulated using a sliding mode controller.

关键词： Asynchronous motor Direct torque control Fuzzy logic control Model Reference Adaptive System Sliding mode control Sliding mode observer

Sliding mode approach applied to sensorless direct torque control of cage asynchronous motor via multi-level inverter

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Protection and Control of Modern Power Systems 2020年第1期5卷 166-175页

作者： Soukaina El Daoudi loubna Lazrak Mustapha Ait Lafkih Laboratory of Automatic Energy Conversion and MicroelectronicsFaculty of Sciences and TechnologySultan Moulay Slimane UniversityBeni MellalMorocco

To improve the robustness and performance of the dynamic response of a cage asynchronous motor,a direct torque control(DTC)based on sliding mode control(SMC)is adopted to replace traditional proportional-integral(PI)and hysteresis *** combination of the proposed strategy with sinusoidal pulse width modulation(SPWM)applied to a three-level neutral point clamped(NPC)inverter brings many advantages such as a reduction in harmonics,and precise and rapid tracking of the *** are performed for a three-level inverter with SM-DTC,a two-level inverter with SM-DTC and the three-level inverter with *** results show that the SM-DTC method achieves better performance in terms of reference tracking,while adoption of the threelevel inverter topology can effectively reduce the *** the SM-DTC to the three-level inverter presents the best solution for achieving efficient and robust *** addition,the use of a sliding mode speed estimator eliminates the mechanical sensor and this increases the reliability of the system.

关键词： Asynchronous cage motor Direct torque control Sinusoidal pulse width modulation Sliding mode control Speed estimator Three-level inverter

Solubility of Solids in Supercritical Fluids: The Mendez-Santiago Teja Model Revisited

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Advances in Chemical Engineering and Science 2015年第3期5卷 413-423页

作者： loubna Nasri Zouhir Bensetiti Departement of Pharmaceutical Engineering University of Constantine 3 Constantine Algeria Unisignal Inc. Brossard Canada

For the development and enhancement of supercritical applications, it is crucial to know the solubility of the considered compound in the supercritical fluid (SCF) in order to determine the conditions to achieve the best outcome. Many models have been developed to calculate supercritical solubility behavior and most can be either a semi empirical relationship or based on an equation of state. The Mendez-Santiago and Teja (MST) model is one of the most semiempirical models used. In this work, a review of the (MST) model from an accuracy and ability viewpoint is accomplished to give concise discussion and so to the proposition of a modification.

关键词： Supercritical Fluids Solubility Dilute Solutions MST Model

Organ Donation and Obstacles: University Student Survey

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Open Journal of Organ Transplant Surgery 2023年第1期11卷 1-14页

作者： Khalid Khaleq Anas Erragh loubna Benaddi Service de réanimation chirurgicale du CHU Ibn Rochd Casablanca Morocco

Background: Organ transplantation has helped improve the quality of life of patients with lethal terminal organ failure. This success is owed to the progress made in many fields such as surgery, immunology…However, in our country Morocco, we are faced with reluctance to donate. The study’s objective is to evaluate the perception of organ donation among university students. Methods: We conducted this cross-sectional study with descriptive and analytical aims. Our target population consisted of 991 university students from eight higher education structures. An anonymous questionnaire was distributed to those students by a single interviewer. The questions of the survey answered four main themes. Thus, two types of studies were done. The first was a descriptive study of the socio-demographic characteristics of the selected population and their knowledge and attitudes about organ donation. The second was an analytical study of the correlation between the socio-demographic characteristics, type and level of education of the target population and their knowledge and attitudes towards organ donation. Results: 97.2% of the respondents have already heard about organ donation. If 836 of the students (84.4%) thought that transplantation could be an effective therapeutic alternative, 155 of the students (15.6%) were not aware of this possibility. Furthermore, 298 students, which means 30.1% of the students, did not know that organ transplantation was practiced in Morocco. The causes of refusal found in our study were numerous. 68.5% of students blamed the lack of information as the main cause of their reluctance. 64.7% were afraid of organ trafficking. 41.1% refused the idea of mutilating the body of the deceased, which could impact the funeral. 37.3% thought that donation would be a violation of the human body according to religious values. 33.9% were against donation because they hoped that the brain-dead patient could wake up. The main results of our survey showed the very f

关键词： Organ Donation Lack of Information Religion Legislation Organ Trafficking

Correlation and Prediction of the Solubility of Solid Solutes in Chemically Diverse Supercritical Fluids Based on the Expanded Liquid Theory

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Advances in Chemical Engineering and Science 2013年第4期3卷 255-273页

作者： loubna Nasri Salima Bensaad Zouhir Bensetiti Department of Pharmaceutical Engineering University Constantine 3 Constantine Algeria

For the proper design of any extraction procedure based on supercritical solvents, it is essential to have a sound knowledge of the solubility data of different compounds and the accurate way to represent it. The solute’s solubility in a supercritical solvent is dependent on the solute, the solvent, and the operating conditions (temperature and pressure). Developing a comprehensive experimental data set is an onerous task and time consuming and, thus, the incentive to develop predictive tools is substantial. In this paper, a technique is presented and tested to correlate and predict solute’s solubility in different supercritical fluids with a methodology based on the expanded liquid theory, in which the solid-fluid equilibrium is modeled using the local composition model of UNIQUAC in which the interaction parameters are related to the solvent reduced density with empiric equations. The most advantages of this model include: it does not require the knowledge of critical properties and sublimation pressure of solid solutes and does take into account the binary interaction between solid solute and solvent. The evaluation of the proposed model capabilities is done by testing it on a large data base consisting of experimental solubility data taken from literature of 33 binary systems solid-SC fluid. The results obtained for both correlation and prediction show good agreement with the experimental data used. For the comparison we have considered some literature models that account for effect of the system conditions (temperature and pressure) in addition to the sublimation pressure of the solute through their introduction of the enhancement factor and a model based on a modified Peng-Robinson equation of state.

关键词： Solubility Modeling Supercritical Fluids Correlation Prediction Expanded Liquid UNIQUAC

Forest Cover Monitoring and Change Detection in Nfifikh Forest (Morocco)

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Journal of Geographic Information System 2018年第2期10卷 219-233页

作者： loubna Khalile Hassan Rhinane Abdelhadi Kaoukaya Hicham Lahlaoi Faculté des Sciences Aï n Chock Université Hassan II-Casablanca Casablanca Morocco

Peri-urban forests are subject to different dynamics due to several factors. Nfifikh forest is a man-made space, located in suburban of Mohammedia City, belonging to Casablanca, Settat Region, and geographically between Casablanca, the economic and business Capital of Morocco and Rabat, the national political capital. Over the past three decades, it has experienced several significant degradations. The aim of this study is to evaluate and quantify the deforestation within the study area using a forest cover change detection of various vegetation indices and subpixel classification to pick out high density plots with Landsat images TM, ETM+ and OLI. Remote sensing is used to highlight the changes caused through Space-Time. This monitoring might help managers to generate forest management plans and to moderate the speed of deforestation and degradation. The results show a significant change in vegetation cover detected between 1987 and 2015. The Density increased in 2001 while it decreased considerably in 2015.

关键词： Subpixel Vegetation Indices Change Detection Monitoring Nfifikh Forest

Secondary Hyperparathyroidism in Dialysis Patients: Short- and Long-Term Outcomes of Conservative Parathyroidectomy

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Open Journal of Nephrology 2024年第2期14卷 147-156页

作者： Imane Saidi Sara Elmaakoul Naima Ouzeddoun loubna Benamar Department of Nephrology-Dialysis-Renal Transplantation IbnSina Hospital Mohammed V University Rabat Morocco

Secondary hyperparathyroidism (HPT) is frequent in dialysis patients. Parathyroidectomy (PTX) is indicated for patients who failed medical therapy. We reviewed the data from 184 dialysis patients who underwent PTX between January 2015 and January 2023. We aimed to evaluate the short and long term outcomes of PTX in dialysis patients, comparing the conservative 3/4 versus 7/8 techniques in this population.166 dialysis patients with secondary HPT were included. A conservative subtotal PTX (sPTX) 7/8 was performed in 72% of patients and sPTX 3/4 in 28% of them. Severe postoperative hypocalcaemiaocurred in 45 patients (27%). Hypocalcaemia was significantly more frequent in the sPTX 7/8 group (p = 0.012). One case of persistent HPT (0.6%) and 20 cases of recurrence (12%) were diagnosed. Recurrence was more frequent in the sPTX 3/4 group (15%). No deaths were reported during the perioperative period.

关键词： Secondary Hyperparathyroidism Dialysis Chronic Kidney Disease Conservative Subtotal Parathyroidectomy

Assessment of Phytoavailability in the Cherry Tomato Plants Exposed to Lead and Chromium in a Nutrient Solution

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Journal of Geoscience and Environment Protection 2017年第9期5卷 176-188页

作者： loubna Azariz Souad Elblidi Ahmed Yahyaoui Mohamed Fekhaoui Laboratory of Zoology and General Biology Department of Biology Faculty of Sciences Mohammed V University in Rabat Rabat Morocco Pollution Unit Department of Zoology and Animal Ecology Scientific Institute Mohammed V University in Rabat Rabat Morocco

The phytoavailability of lead and chromium in cherry tomatoes Lycopersicon esculentum was studied both at the level of different parts of the plant (roots, stem, leaves and fruits) and at the level of its concentration in water and cultivation soil of. Two experiments are thence carried out by planting in bioponics, in a patented BIOTOP device, plants which are exposed via their root system to concentrations of 5 ppm, 10 ppm and 20 ppm of each contaminant (lead or chromium) in a nutrient solution. The results show that lead accumulates mainly in the roots with a significant amount as to allow its translocation into the stem and leaves, while only a small amount reaches the fruit. The results also show that when the concentration increases the lead content in the roots also increases, but decreases in the fruits with three floral bouquets. Conversely, the chromium substance decreases in the roots and increases in the fruit. Based on these results, we note that the average distribution of lead in the edible part of the plant is much higher than that of chromium, and also lead presence in the plant is higher compared to that of chromium.

关键词： Cherry Tomatoes Lead Chromium Phytoavailability Bioponics

De Novo Glomerular Diseases after COVID-19 Vaccination: Consequence or Coincidence?

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Open Journal of Nephrology 2024年第2期14卷 233-239页

作者： Qods Yacoubi Salima Serroukh loubna Benamar Naima Ouzeddoun Tarik Bouattar Department of Nephrology-Dialysis-Renal Transplantation CHU Ibn-Sina Mohammed V University Rabat Morocco

Introduction: Vaccination against COVID-19 has proven highly effective in preventing severe forms of the disease. However, the literature reports several cases associating renal damage and the anti-COVID vaccine. The aim of our work was to report a case series of patients who developed glomerulopathy after anti-COVID-19 vaccine. We evaluated the type of vaccine, the clinico-biological profile, and the anatomopathological, therapeutic and evolutionary aspects. Material and Methods: Prospective descriptive study conducted at the Nephrology Department of CHU IbnSina in Rabat between December 2021 and June 2022 including 9 patients who presented with glomerulopathy after the 1st dose of anti-COVID-19 vaccine. We excluded patients followed for nephropathy. Results: The mean age of our patients was 33 ± 16 years with a sex ratio of 0.8. Six patients received an inactivated vaccine, 2 patients received a mRNA vaccine and 1 patient received a viral vector vaccine. The mean delay between the onset of signs and the date of the first vaccine dose was 3.1 +/? 0.65 months (1 - 6 months). All patients had a nephrotic syndrome, 2 pure and 7 impure: 3 patients had acute renal failure and microscopic hematuria, 2 patients had microscopic hematuria and 2 patients had acute renal failure. Histologically, focal segmental glomerulosclerosis (FSGS) was noted in 4 patients, lupus nephropathy in 3, and membranous nephropathy (MN) in 2. Specific treatment was administered to each patient, depending on the histological type of renal involvement and the context. After 6 months, complete remission was achieved in 5 patients, with no improvement in 2, and one patient was placed on hemodialysis. One patient died of another cause. Conclusion: The causal link between anti-COVID 19 vaccination and renal disease is highly probable, but remains to be confirmed.

关键词： Glomerulopathy Vaccination COVID-19