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CES Transactions on Electrical Machines and Systems 2023年第1期7卷 54-62页

作者： ghada a.abdel aziz Rehan Ali Khan Power Electronics and Energy Conversion Department Electronics Research InstituteCairo11843Egypt Department of Electrical Engineering University of Science&TechnologyBannu28100Pakistan IEEE

In this paper,a robust torque speed estimator(RTSE)for linear parameter changing(LPC)system is proposed and designed for an encoderless five-phase permanent magnet assisted synchronous reluctance motor(5-phase PMa-SynRM).This estimator is utilized for estimating the rotor speed and the load torque as well as can solve the speed sensor fault problem,as the feedback speed information is obtained directly from the virtual *** addition,this technique is able to enhance the 5-phase PMa-SynRM performance by estimating the load torque for the real time *** stability analysis of the proposed estimator is performed via Schur complement along with Lyapunov ***,for improving the 5-phase PMa-SynRM performance,five super-twisting sliding mode controllers(ST-SMCs)are employed with providing a robust response without the impacts of high chattering problem.A super-twisting sliding mode speed controller(ST-SMSC)is employed for controlling the PMa-SynRM rotor speed,and four super-twisting sliding mode current controllers(ST-SMCCs)are employed for controlling the 5-phase PMa-SynRM *** stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed RTSE and the ST-SMSC with ST-SMCCs approach for a 750-W 5-phase PMa-SynRM under load disturbance,parameters variations,single open-phase fault,and adjacent two-phase open circuit fault conditions.

关键词： Five-phase permanent magnet assisted synchronous reluctance motor Encoderless control Supertwisting sliding mode control Torque-speed estimator

Adaptive Gain Tuning Rule for Nonlinear Sliding-mode Speed Control of Encoderless Three-phase Permanent Magnet Assisted Synchronous Motor

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中国电工技术学会电机与系统学报(英文) 2023年第3期7卷 301-310页

作者： ghada a.abdel aziz Rehan Ali Khan IEEE Power Electronics and Energy Conversion Department Electronics Research InstituteCairo 11843Egypt Department of Electrical Engineering University of Science&TechnologyBannuPakistan.

In this paper, an adaptive gain tuning rule is designed for the nonlinear sliding mode speed control(NSMSC) in order to enhance the dynamic performance and the robustness of the permanent magnet assisted synchronous reluctance motor(PMa-Syn RM) with considering the parameter uncertainties. A nonlinear sliding surface whose parameters are altering with time is designed at first. The proposed NSMSC can minimize the settling time without any overshoot via utilizing a low damping ratio at starting along with a high damping ratio as the output approaches the target set-point. In addition, it eliminates the problem of the singularity with the upper bound of an uncertain term that is hard to be measured practically as well as ensures a rapid convergence in finite time, through employing a simple adaptation law. Moreover, for enhancing the system efficiency throughout the constant torque region, the control system utilizes the maximum torque per ampere technique. The nonlinear sliding surface stability is assured via employing Lyapunov stability theory. Furthermore, a simple sliding mode estimator is employed for estimating the system uncertainties. The stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed speed estimation and the NSMSC approach for a 1.1-k W PMa-Syn RM under different speed references, electrical and mechanical parameters disparities, and load disturbance conditions.

关键词： Permanent magnet assisted synchronous reluctance motor Nonlinear sliding mode speed control Speed estimation Parameter uncertainties Sliding mode estimator

Model Predictive Current Control for Low-Cost Shunt Active Power Filter

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1589-1598页

作者： Ali a.abdel-aziz Mohamed A.Elgenedy Barry W.Williams the Electronic and Electrical Engineering Department Strathclyde UniversityGlasgowG11XQUK School of Computing Engineering and the Built Environment(SCEBE)Glasgow Caledonian UniversityGlasgowG40BAUK

Performance of a three-phase shunt active power filter(SAPF)relies on the capability of the controller to track the reference ***,designing an accurate current controller is crucial to guarantee satisfactory SAPF *** paper presents a model predictive current controller(MPCC)for a low-cost,four-switch,shunt active power filter for power quality improvement.A four-switch,B4,converter topology is adopted as an SAPF,hence offering a simple,robust,and low-cost *** addition,to further reduce overall cost,only two interfacing filter inductors,instead of three,are used to eliminate switching current *** proposed SAPF model MPCC is detailed for implementation,where simulation and experimental results validate effectiveness of the proposed control algorithm showing a 20%improvement in total harmonic distortion compared with a conventional hysteresis band current controller.

关键词： Four-switch converter harmonic distortion model predictive current control power quality shunt active power filter

My Dream of Translation and Predestination With China

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China News Release 2024年第4期 24-27页

作者： abdel aziz Hamdi the Chinese language department of Al-Azhar University in Egypt

Many years later,when looking back on my decision,I can’t help but think that a few things in life seem to be coincidences,but in fact they are imperceptibly predestined,just like my dream of translation and my experience with the Chinese *** 1977,when I was 18 years old,Ain Shams University in Egypt established the Chinese *** was the only Chinese department among Egyptian universities for the following two decades.

关键词： looking dream translation

Mitigating diabetes-related complications:Empowering metformin with cholecalciferol and taurine supplementation in type 2 diabetic rats

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World Journal of Diabetes 2024年第8期15卷 1778-1792页

作者： Mai S Attia Fadwa Ayman Mohamed S Attia Galal Yahya Mansour H Zahra Magdi Mohamed Ibrahim Khalil abdel aziz A Diab Department of Zoology Faculty of ScienceZagazig 44519Egypt Department of Pharmaceutics Faculty of PharmacyZagazig 44519Egypt Department of Microbiology and Immunology Faculty of PharmacyZagazig UniversityZagazig 44519Egypt Department of Biochemistry Faculty of MedicineZagazig 44519Egypt

BACKGROUND Type 2 diabetes is one of the most prevalent chronic diseases worldwide,significantly impacting patients'quality of *** treatment options like metformin(MET)effectively counteract hyperglycemia but fail to alleviate diabetes-associated complications such as retinopathy,neuropathy,nephropathy,hepatopathy,and cardiovascular *** To propose the supplementation of cholecalciferol(CHO)and taurine(TAU)to enhance MET efficacy in controlling diabetes while minimizing the risk of associated *** The study involved sixty rats,including ten non-diabetic control rats and fifty experimental rats with type 2 diabetes induced by *** experimental rats were further subdivided into positive control and treatment *** four treatment groups were randomly allocated to a single MET treatment or MET combined with supplements either CHO,TAU,or *** Diabetic rats exhibited elevated levels of glucose,insulin,Homeostasis Model Assessment of Insulin Resistance(HOMA-IR),glycated hemoglobin percentage,lipid markers,aspartate aminotransferase,and malondialdehyde,along with reduced levels of antioxidant enzymes(catalase and superoxide dismutase).The administration of CHO and TAU supplements alongside MET in diabetic rats led to a noticeable recovery of islet *** antioxidative,anti-inflammatory,and anti-apoptotic properties of the proposed combination therapy significantly ameliorated the aforementioned *** The supplementation of CHO and TAU with MET showed the potential to significantly improve metabolic parameters and protect against diabetic complications through its antioxidative,anti-inflammatory,and antiapoptotic effects.

关键词： Diabetes complications Metformin Cholecalciferol Taurine Glycated hemoglobin% Antioxidant

Attitude dynamics and control of spacecraft using geomagnetic Lorentz force

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Research in Astronomy and Astrophysics 2015年第1期15卷 127-144页

作者： Yehia a.abdel-aziz Muhammad Shoaib National Research Institute of Astronomy and Geophysics (NRIAG) Helwan Cairo 11721Egypt University of Hail Department of Mathematics PO BOX 2440 Kingdom of Saudi Arabia

Attitude stabilization of a charged rigid spacecraft in Low Earth Orbit using torques due to Lorentz force in pitch and roll directions is considered. A spacecraft that generates an electrostatic charge on its surface in the Earth’s magnetic field will be subject to perturbations from the Lorentz force. The Lorentz force acting on an electrostatically charged spacecraft may provide a useful thrust for controlling a spacecraft’s orientation. We assume that the spacecraft is moving in the Earth’s magnetic field in an elliptical orbit under the effects of gravitational, geomagnetic and Lorentz torques. The magnetic field of the Earth is modeled as a non-tilted dipole.A model incorporating all Lorentz torques as a function of orbital elements has been developed on the basis of electric and magnetic fields. The stability of the spacecraft orientation is investigated both analytically and numerically. The existence and stability of equilibrium positions is investigated for different values of the charge to mass ratio（α＊）. Stable orbits are identified for various values of α＊. The main parameters for stabilization of the spacecraft are α＊and the difference between the components of the moment of inertia for the spacecraft.

关键词： space vehicles atmospheric effects celestial mechanics kinematics and dynamics

Equilibria of a charged artificial satellite subject to gravitational and Lorentz torques

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Research in Astronomy and Astrophysics 2014年第7期14卷 891-902页

作者： Yehia a.abdel-aziz Muhammad Shoaib National Research Institute of Astronomy and Geophysics (NRIAG) HelwanCairo 11721Egypt University of Hail Department of MathematicsPO Box 2440Kingdom of Saudi Arabia

The attitude dynamics of a rigid artificial satellite subject to a gravity gradient and Lorentz torques in a circular orbit are considered. Lorentz torque is developed on the basis of the electrodynamic effects of the Lorentz force acting on the charged satellite＇s surface. We assume that the satellite is moving in a Low Earth Orbit in the geomagnetic field, which is considered to be a dipole. Our model of torque due to the Lorentz force is developed for an artificial satellite with a general shape, and the nonlinear differential equations of Euler are used to describe its attitude orientation. All equilibrium positions are determined and conditions for their existence are *** numerical results show that the charge q and radius ρ0of the center of charge for the satellite provide a certain type of semi-passive control for the attitude of the satellite. The technique for this kind of control would be to increase or decrease the electrostatic screening on the satellite. The results obtained confirm that the change in charge can affect the magnitude of the Lorentz torque, which can also affect control of the satellite. Moreover, the relationship between magnitude of the Lorentz torque and inclination of the orbit is investigated.

关键词： space vehicles -- atmospheric effects -- celestial mechanics -- kine-matics and dynamics

Ethnobotanical Study of Medicinal Plants Used for Treating Urinary Tract Infections in N’Djamena (Chad)

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American Journal of Plant Sciences 2024年第1期15卷 46-55页

作者： Alhadj Djidda Mahamat Soudy Imar Djibrine Hamit Mht Alio Abakar Tadjadine Emmanuel Issa Issa Ramat Adam abdel-aziz Arada Baroua Abouna Elisabeth Ngo Bum Laboratory of the Faculty of Human Health Sciences of the University of N’Djamena N’Djamena Chad Faculty of Sciences of the University of Maroua Maroua Cameroun Food Quality Control Centre (CECOQDA) N’Djamena Chad National Reference University Hospital of N’Djamena N’Djamena Chad Lute Sectorial Programme against AIDS and Hepatitis (PSLS) N’Djamena Chad Research and Livestock Institute for Development (IRED) N’Djamena Chad

Introduction: Infection disease is a real publique health problem. The rise of resistance for modern antibiotic in infections treatment imposed us order alternatives. The study objective was to contribute in the knowledge of medicinal plants uses in urinary infections treatment in N’Djamena (Chad) in view for amelioration the traditional medicine in future. Methodology: The study was conducted in the city of N’Djamena in the Republic of Chad that interviewed 60 traditherapists on using 11 plants for urinary tract infections treatment. The methodology of this study consisted of the knowledge of medicinal plants that used by traditherapists, and the plants identification was done in the laboratory of IRED at Farcha. Results: A total of 60 traditherapists was interrogated on the plants used in the treatment of urinary tract infections among the population of N’Djamena. The majority of traditherapists interrogated in this study were male with the rate of 61.67% against female with the rate of 38.33%. The age range of traditherapists was between 20 to 80 years, 25 (41.67%) from the age range between 30 - 50 years and 35 (58.33%) in age range from 50 to 70 years. For the origin of their knowledge, the study showed that 72% of traditherapists inherited the knowledge from their family, while 15% inherited from the family and from training. The ethnic groups of the traditherapists were Sara (16%), Maraba (12%) and Massa (11%). According to the results, 18.33% were illiterates, 49% attended primary school and 33.34% the secondary school. Our study found that 11 species of plants belonging to 11 families were used in the treatment of urinary tract infection and the Ziziphus spina-christi was the most represented. According to traditherapists the Ziziphus spina-christi, Cassia obovata and Euphorbia hirta were the most frequent plants used in the urinary tract infections treatment. The parts of plants used in the treatment were leaves and bark, grained leaves and entire plants w

关键词： Urinary Infections Medicinal Plant and Traditherapists

Microbial,immune and antioxidant responses of Nile tilapia with dietary nano-curcumin supplements under chronic low temperatures

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Aquaculture and Fisheries 2024年第1期9卷 57-65页

作者： Mohammed F.El Basuini Mohamed A.A.Zaki abdelaziz M.El-Hais Mohamed G.Elhanafy Emad H.El-Bilawy Amr I.Zaineldin Mohamed F.a.abdel-aziz Ibrahim A.Abouelsaad Ibrahim TEl-Ratel Kumbukani Mzengereza Ronick S.Shadrack Islam I.Teiba Faculty of Agriculture Tanta UniversityTanta31527Egypt King Salman International University South Sinai46618Egypt Faculty of Agriculture Alexandria UniversityAlexandria21526Egypt Animal Health Research Institute(AHRI-DOKI) Agriculture Research CenterGiza12619Egypt Fish Rearing Lab. Aquaculture DivisionNational Institute of Oceanography and FisheriesAlexandria21556Egypt Horticulture Department Faculty of AgricultureDamanhour UniversityDamanhur22511Egypt Department of Poultry Production Faculty of AgricultureDamietta UniversityDamietta34517Egypt Laboratory of Aquatic Animal Nutrition Faculty of FisheriesKagoshima UniversityKagoshima890-0065Japan Department of Aquatic and Fisheries Science Mzuzu UniversityMzuzuPrivate Bag 201Malawi Faculty of Aquaculture and Marine Fisheries Arish UniversityArish45516Egypt

A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapia under chronic low temperature(21.02±0.11◦C).Fishes(n=225;Initial weight=4.39±0.08 g/fish)were randomly stocked at 15 fish/tank for five experimental groups in *** low-temperature circumstances,dietary curcumin in nano form showed no notable alteration in growth variable,nutrient efficiency,digestive enzymes efficiency,biometric indices,survival rates,and hematological ***,the serum of fishes with nano curcumin diets under low-temperature stress displayed higher total protein as well as lower glucose,cortisol,and total cholesterol compared with the control ***,fish fed nano curcumin diets displayed higher lysozyme and bactericidal activities compared to the control group and the best performance was found at dietary nano curcumin level of≥100 ***,groups fed the basal diet demonstrated the poorest antioxidant capacity,and the best superoxide dismutase(SOD)and glutathione peroxidase(GPx)existed in fish with nano curcumin diets while the best catalase(CAT)efficiency occurred at higher nano curcumin levels≥100 *** addition,higher counts of intestinal microbiota in terms of total bacterial count(TBC),total yeast and molds count(TYMC),and coliform were noticed in fish consumed the basal diet compared to groups fed on nano curcumin *** conclusion,incorporating nano curcumin at a level of≥100 mg/kg diet(particularly at 150 mg/kg)improved a non-specific immune response,antioxidant,and healthier gastrointestinal microbiota in Nile tilapia under chronic low-temperature stress.

关键词： Nano curcumin Gastrointestinal microbiota Antioxidants Non-specific immune responses Temperature stress

Hematological Alterations in an Eastern Sudanese Chronic Kidney Disease Patient Population

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Open Journal of Urology 2024年第6期14卷 359-367页

作者： Mohammed Omer Abaker Gibreel Sundus Kamal Ibrahim Wijdan abdel aziz Hassan Manar Yahia Mahjoub Leyla Mohammed Kheir Hamid Hibatellah Majzoub Abbas Nuha Fouzi Mohammed Secretariat of Academic Affairs Port Sudan Ahlia University Port Sudan Sudan Department of Hematology and Immunohematology College of Graduate Studies Port Sudan Ahlia University Port Sudan Sudan

Background: Chronic Kidney Disease (CKD), associated with a slow and progressive loss of kidney function over a period of several years, is an important clinical disaster with an increasing rate of morbidity and mortality especially in the least developed countries. Many hematological parameters are thought to alter dramatically during the course of the disease. These include white blood cells, red blood cells, and platelets. Methods: We tried, retrospectively, to evaluate the peripheral blood hematological alterations in a group of patients undergoing hemodialysis in an eastern Sudan dialysis center to add local medical information. Results: Anemia (Low hemoglobin and hematocrit) was detected in 94% of the patients’ group. Mean Erythrocyte count (3.32vs.4.76 (×109/L)), Hemoglobin concentration (9.4vs.13 (g/dl)), Hematocrit (28.7vs.38.7 (L/L)) and platelet count (296 vs. 238 (×109/L)) were significantly lower in the patients’ group than in the control group (P-values Conclusion: Five out of eight studied parameters (Red cell count, hemoglobin, hematocrit, mean cell hemoglobin concentration, and platelets count) have shown a significant alteration in CKD patients. As the complete blood count (CBC) test is the most utilized test in clinical laboratory practice, these alterations may be considered as early indicators for CKD. Furthermore, all patients with CKD must be routinely checked for these alterations.

关键词： Chronic Kidney Disease Chronic Renal Failure Hematological Alterations CBC Eastern Sudan Hemodialysis