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Effect of Heart Failure on Acute Ischemic Stroke Severity

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Open Journal of Medical Imaging 2014年第3期4卷 103-107页

作者： Taha Kamel Alloush Mahmoud Haroun ibrahim Nahed Salah El-Dein Ahmed Ghada Samir El-Shahed Lobna M. El-Nabil El-Sayed mohamed hamdy ibrahim Hosam Ahmed Azmy Faculty of Medicine Ain Shams University Cairo Egypt Ministry of Health Cairo Egypt

Objectives: To assess the impact of heart failure diseases on stroke severity and short term (1 month mortality). Materials and Methods: Totally, 200 patients admitted to Ain Shams university specialized hospital, were diagnosed clinically to have acute ischemic stroke within 3 days. History taking about previous heart disease was taken, and full general and neurological examinations were done. Full metabolic profile, cardiac examination and investigations were done. Carotid duplex, MRI stroke protocol and lastly clinical reevaluation using NIH Stroke Scale (NIHSS) after 1 month from stroke onset were done. Results: Patients with systolic dysfunction (EF ≤ 40%) had lacunar infarction in 18.75% of cases, partial anterior circulation infarction in 62.5% of cases, posterior circulation infarction in 6.25% of cases and total anterior circulation infarction in 12.5% of cases. Leucoaraiosis was present in 87% of cases and significant intracranial vessel stenosis was showed in 87.5% who had done MRI. Their median NIHSS score at admission was 10.5 with IQR of 5 - 21 and at follow-up it was 5 with IQR of 2.5 - 10.5. At follow-up 22.7% (5 patients) were dead. Conclusion: Systolic dysfunction (EF < 40) i.e. heart failure has no significant effect on stroke severity and 1 month follow up prognosis.

关键词： Heart Failure Stroke Prognosis Ejection Fraction

State Observer Based Dynamic Fuzzy Logic System for a Class of SISO Nonlinear Systems

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International Journal of Automation and computing 2013年第2期10卷 118-124页

作者： mohamed hamdy Department of Industrial Electronics and Control Engineering Faculty of Electronic Engineering Menofia University

This paper presents an observer based dynamic fuzzy logic system （DFLS） scheme for a class of unknown single-input single-output （SISO） nonlinear dynamic systems with external disturbances. The proposed approach does not need the availability of the state variables. Within this scheme, the DFLS is employed to identify the unknown nonlinear dynamic system. The control law and parameter adaptation laws of the DFLS are derived based on Lyapunov synthesis approach. The control law is robustfied in H∞ sense to attenuate external disturbance, model uncertainties, and fuzzy approximation errors. It is shown that under appropriate assumptions, it guarantees the boundedness of all the signals in the closed-loop system and the asymptotic convergence to zero of tracking errors. The proposed method is applied to an inverted pendulum system to verify the effectiveness of the proposed algorithms.

关键词： Single-input single-output (SISO) nonlinear system dynamic fuzzy logic system (DFLS) observer Lyapunov synthesis approach stability analysis.

Design of adaptive intuitionistic fuzzy controller for synchronisation of uncertain chaotic systems

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CAAI Transactions on Intelligence Technology 2020年第4期5卷 237-246页

作者： mohamed hamdy Salah Helmy mohamed Magdy Department of Industrial Electronics and Control Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf-32952Egypt Department of Mechatronics Engineering Higher Institute of Engineering and TechnologyEl-Mahalla El-Kobra-31951Egypt

This study presents the synchronisation between two non-linear Lorenz chaotic systems using an adaptive intuitionistic fuzzy controller(AIFC).This problem is solved in the presence of external disturbances and *** classes of Lorenz systems have been formulated one as the master and the other as the *** master and slave systems have different initial *** different initial conditions,both systems *** is called the butterfly effect that rules the behaviour of chaotic *** is chosen as a different method that has not been used before to synchronise the chaotic *** scaling factors of the inputs and the output of the intuitionistic fuzzy controller(IFC)are tuned using the artificial bee colony(ABC)algorithm depending on a specified objective *** IFC stability is studied when it is applied to synchronise the Lorenz *** simulation results achieved to assess the adequacy of the proposed control and to exhibit its dependability to synchronise the Lorenz system.

关键词： function. chaotic specified

Corrosion and corrosion-fatigue behavior of magnesium metal matrix composites for bio-implant applications:A review

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Journal of Magnesium and Alloys 2023年第4期11卷 1125-1161页

作者： Hassan Delavar Amirhossein Jabbari Mostahsan hamdy ibrahim School of Mechanical Engineering Iran University of Science and TechnologyTehranIran Department of Mechanical Engineering Sharif University of TechnologyTehranIran Mechanical Engineering Department University of Tennessee at ChattanoogaChattanoogaTN 37403USA

Recently,the topic of bioresorbable metals,with much focus on magnesium for bone implant applications,has been an area of considerable ***,it could be argued that magnesium is the most promising biodegradable material currently being studied for use as an orthopedic skeletal fixation and joint replacement ***,the fast degradation rate of magnesium-based materials in the physiological environment negatively affects their mechanical integrity and hence limits their biomedical *** most critical conditions may occur when the implant is subjected to a corrosive physiological environment and a fluctuating load during daily ***,numerous studies have been published on the synthesis,alloying,and coating of magnesium to control degradation rate and increase strength and *** the materials and strategies employed to achieve these goals,magnesium-based biocomposites have exhibited superior mechanical properties and acceptable ***,there is a lack of understanding of their corrosion and corrosion-fatigue *** understanding is necessary to qualify these new materials for various bio-implant *** this end,this paper reviews the recent advances in the corrosion and corrosion-fatigue behavior of magnesium-based *** also provides a comprehensive discussion of different factors that influence the biocompatibility,corrosion,fatigue,and corrosion-fatigue of magnesium-based biocomposites as potential implant *** study emphasizes that despite the abundance of various studies on the corrosion behavior of magnesium-based biocomposites,there is an imperative need for more fatigue and corrosion-fatigue studies.

关键词： Magnesium biocomposites Biodegradable implants Corrosion Fatigue Corrosion-fatigue

Comparative Study of Different Decoupling Schemes for TITO Binary Distillation Column via PI Controller

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IEEE/CAA Journal of Automatica Sinica 2018年第4期5卷 869-877页

作者： mohamed hamdy Abdalhady Ramadan Belal Abozalam Industrial Electronics and Control Engineering Department Faculty of Electronic EngineeringMenoufia UniversityMenouf-23952Egypt Badr Petroleum Company(BAPETCO) CairoEgypt

This paper presents a comparative study of different decoupling control schemes for a two-input, two-output(TITO) binary distillation column via proportional-integral(PI)controller. The key idea behind this paper is designing two novel fuzzy decoupling schemes that depend on human knowledge,instead of the system mathematical model used in conventional decoupling schemes. Based on conventional and inverted decoupling schemes, fuzzy and inverted fuzzy decoupling schemes are developed. The control effect is compared using simulation results for the proposed two schemes with conventional decoupling and inverted decoupling. The proposed fuzzy decoupling schemes are easy to realize and simple to design, besides they have a good decoupling capability. Two methods are used to prove asymptotic stability of each loop and the entire closed-loop system by applying the proposed fuzzy decoupling-based PI *** Wood and Berry model of a binary distillation column is used to illustrate the applicability of the proposed schemes.

关键词： Binary distillation column conventional decoupling fuzzy decoupling proportional-integral(PI) controller stability analysis

Observer-based Adaptive Fuzzy Control for a Class of Nonlinear Time-delay Systems

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International Journal of Automation and computing 2013年第4期10卷 275-280页

作者： Hassan A. Yousef mohamed hamdy Department of Electrical and Computer Engineering College of Engineering Sultan Qaboos University Department of Industrial Electronics and Control Engineering Faculty of Electronic Engineering Menofia University

An observer-based adaptive fuzzy control is presented for a class of nonlinear systems with unknown time delays. The state observer is first designed, and then the controller is designed via the adaptive fuzzy control method based on the observed states. Both the designed observer and controller are independent of time delays. Using an appropriate Lyapunov-Krasovskii functional, the uncertainty of the unknown time delay is compensated, and then the fuzzy logic system in Mamdani type is utilized to approximate the unknown nonlinear functions. Based on the Lyapunov stability theory, the constructed observer-based controller and the closed-loop system are proved to be asymptotically stable. The designed control law is independent of the time delays and has a simple form with only one adaptive parameter vector, which is to be updated on-line. Simulation results are presented to demonstrate the effectiveness of the proposed approach.

关键词： Observer adaptive fuzzy control nonlinear systems time delay stability.

Laterites-bearing REEs,Wadi Natash,Southeastern Desert,Egypt

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Journal of Rare Earths 2010年第3期28卷 471-476页

作者： mohamed El-Ahmady ibrahim Nuclear Materials Authority P.O.Box530EL MaadiCairoEgypt

The present paper recorded the occurrence of laterites-bearing REEs in Natash *** laterite deposits occur as horizons(5-15 m in thickness) at the boundary between the Cretaceous sandstones,and Natash *** was recorded in more than twenty six occurrence distributed over an area of about 500 km2 along and around Wadi *** ranges in color from light-grey,dark-grey to *** distribution of laterite deposits is structural *** results of laterites proved the...

关键词： Natash flows laterites clay minerals REEs

Wear properties of copper and copper composites powders consolidated by high-pressure torsion

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Friction 2020年第2期8卷 433-450页

作者： mohamed ibrahim Abd El AAL Mechanical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addawaser 11991Saudi Arabia Mechanical Design&Production Department Faculty of EngineeringZagazig UniversityZagazig 44519Egypt

The wear characteristics of Cu and Cu-SiC composite microsize powders consolidated by cold compaction combined with sintering or high-pressure torsion(HPT)were *** HPT processed(HPTed)samples with bimodal and trimodal microstructures and fine Cu grains and SiC particle sizes have superior hardness,reasonable ductility level,and high wear *** wear mass loss and coefficient of friction of HPTed samples were remarkably lower than that of cold-compacted and sintered samples as well as that of micro and nano Cu and Cu-SiC composites from previous *** sample fabrication method has an apparent influence on the wear *** wear mechanism was converted from adhesive,delamination,three-body mechanism,grooves(take off the SiC particles),and cracks into abrasive wear after *** can be considered a dominant wear mechanism in all *** worn surface morphology and analysis support the relationship between wear mechanism and characteristics.

关键词： Cu-SiC composite powders high-pressure torsion(HPT) fine and coarse grains wear characteristics worn surface morphology

Revolutionizing diabetic retinopathy screening and management:The role of artificial intelligence and machine learning

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World Journal of Clinical Cases 2025年第5期13卷 1-12页

作者： Mona mohamed ibrahim Abdalla Jaiprakash Mohanraj Department of Human Biology School of MedicineInternational Medical UniversityBukit Jalil 57000Kuala LumpurMalaysia

Diabetic retinopathy(DR)remains a leading cause of vision impairment and blindness among individuals with diabetes,necessitating innovative approaches to screening and *** editorial explores the transformative potential of artificial intelligence(AI)and machine learning(ML)in revolutionizing DR *** and ML technologies have demonstrated remarkable advancements in enhancing the accuracy,efficiency,and accessibility of DR screening,helping to overcome barriers to early *** technologies leverage vast datasets to identify patterns and predict disease progression with unprecedented precision,enabling clinicians to make more informed ***,AI-driven solutions hold promise in personalizing management strategies for DR,incorpo-rating predictive analytics to tailor interventions and optimize treatment *** automating routine tasks,AI can reduce the burden on healthcare providers,allowing for a more focused allocation of resources towards complex patient *** review aims to evaluate the current advancements and applic-ations of AI and ML in DR screening,and to discuss the potential of these techno-logies in developing personalized management strategies,ultimately aiming to improve patient outcomes and reduce the global burden of *** integration of AI and ML in DR care represents a paradigm shift,offering a glimpse into the future of ophthalmic healthcare.

关键词： Diabetic retinopathy Artificial intelligence Machine learning Screening Management Predictive analytics Personalized medicine