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Improved Control in Single Phase Inverter Grid-Tied PV System Using Modified PQ Theory

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Intelligent Automation & Soft Computing 2023年第8期37卷 2441-2457页

作者： Nur Fairuz mohamed Yusof Dahaman Ishak Muhammad Ammirrul Atiqi Mohd Zainuri Muhammad Najwan Hamidi Zuhair Muhammed Alaas mohamed Mostafa ramadan ahmed Faculty of Electrical Engineering&Technology Universiti Malaysia Perlis02600ArauMalaysia School of Electrical&Electronic Engineering Universiti Sains Malaysia14300Nibong TebalMalaysia Department of Electrical Electronic and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaSelangor43600Malaysia School of Engineering Jazan UniversityJazanSaudi Arabia Faculty of Technology and Education Helwan UniversityCairoEgypt

Grid-connected reactive-load compensation and harmonic control are becoming a central topic as photovoltaic(PV)grid-connected systems *** research aims to produce a high-performance inverter with a fast dynamic response for accurate reference tracking and a low total har-monic distortion(THD)even under nonlinear load applications by improving its control *** proposed system is expected to operate in both stand-alone mode and grid-connected *** stand-alone mode,the proposed controller supplies power to critical loads,alternatively during grid-connected mode provide excess energy to the utility.A modified variable step incremental conductance(VS-InCond)algorithm is designed to extract maximum power from *** the proposed inverter controller is achieved by using a modified PQ theory with double-band hysteresis current controller(PQ-DBHCC)to produce a reference current based on a decomposition of a single-phase load *** nonlinear rectifier loads often create significant distortion in the output voltage of single-phase inverters,due to excessive current harmonics in the ***,the proposed method generates a close-loop reference current for the switching scheme,hence,minimizing the inverter voltage distortion caused by the excessive grid current *** simulation findings suggest the proposed control technique can effectively yield more than 97%of power conversion efficiency while suppressing the grid current THD by less than 2%and maintaining the unity power factor at the grid *** efficacy of the proposed controller is simulated using MATLAB/Simulink.

关键词： Hysteresis current controller incremental conductance nonlinear load PQ theory single-phase inverter

Gut virome:New key players in the pathogenesis of inflammatory bowel disease

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World Journal of Methodology 2025年第2期15卷 27-43页

作者： Helal F Hetta Rehab ahmed Yasmin N ramadan Hayam Fathy Mohammed Khorshid mohamed M Mabrouk Mai Hashem Department of Medical Microbiology and Immunology Faculty of MedicineAssiut UniversityAssiut 71515Egypt Division of Microbiology Immunology and BiotechnologyFaculty of pharmacyUniversity of TabukTabuk 71491Saudi Arabia Division of Microbiology Immunology and BiotechnologyDepartment of Natural Products and Alternative MedicineFaculty of PharmacyUniversity of TabukTabuk 71491Saudi Arabia Department of Internal Medicine Division HepatogastroenterologyAssiut UniversityAssiut 71515Egypt Department of Clinical Research Egyptian Developers of Gastroenterology and Endoscopy FoundationCairo 11936Egypt Department of Internal Medicine Faculty of Medicine.Tanta UniversityTanta 31527Egypt Department of Tropical Medicine Gastroenterology and HepatologyAssiut University HospitalAssiut 71515Egypt

Inflammatory bowel disease(IBD)is a chronic inflammatory illness of the *** the mechanism underlying the pathogenesis of IBD is not fully under-stood,it is believed that a complex combination of host immunological response,environmental exposure,particularly the gut microbiota,and genetic suscept-ibility represents the major *** gut virome is a group of viruses found in great frequency in the gastrointestinal tract of *** gut virome varies greatly among individuals and is influenced by factors including lifestyle,diet,health and disease conditions,geography,and *** majority of research has focused on the significance of gut bacteria in the progression of IBD,although viral populations represent an important component of the *** conducted this review to highlight the viral communities in the gut and their expected roles in the etiopathogenesis of IBD regarding published research to date.

关键词： Inflammatory bowel disease Pathogenesis Gut virome Bacteriophage Eukaryotic viruses

Summary of the current guidelines for managing iatrogenic colorectal perforations and the evolving role of endoluminal vacuum therapy

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World Journal of Clinical Cases 2025年第6期13卷 1-8页

作者： ahmed Tawheed Ibrahim Halil Bahcecioglu Mehmet Yalniz Mubin Ozercan Ali Cagri Oral mohamed El-Kassas Department of Endemic Medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt Department of Gastroenterology Firat UniversityElazig 23119Türkiye Liver Disease Research Center College of MedicineKing Saud UniversityRiyadh 7805Saudi Arabia

Colonoscopy represents a safe procedure that is widely used in medical practice either to diagnose or treat various gastrointestinal *** the last few years,the incidence rate of perforations in colonoscopic procedures has increased,especially in therapeutic *** recent advancements in endoscopic techniques and gastrointestinal tumoral resection procedures such as endoscopic mucosal resection,endoscopic full-thickness resection,and endoscopic submucosal dissection(ESD)could be a risk factor for this increased *** incidence rate of mortality of serious colonoscopic perforations is 7.1%.The management plan for these perforations starts with conservative treatment in mild cases,endoscopic closure,and surgical management in severe ***,endoluminal vacuum therapy was found to be effective in the management of colorectal perforations and this has been reported in multiple case *** editorial provides an overview of the current guidelines for the management of iatrogenic colorectal *** insights are from the perspectives of endoscopists and *** also present a management algorithm based on the guidelines of the European Society of Gastrointestinal Endoscopy,the American Gastroenterological Association,and the World Society of Emergency *** also discussed in brief the use of endoluminal vacuum therapy in colorectal perforations.

关键词： Colon Rectum Iatrogenic colonic perforation Colonoscopy Guidelines Endovacuum Endolumical vacuum therapy Endoscopic management

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid ahmed Tadjer Abdelhakim Idir Kong Fah Tee mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

Solar thermochemical reactions Ⅱ:Synthesis of 2-aminothiophenes via Gewald reaction induced by solar thermal energy

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Chinese Chemical Letters 2008年第7期19卷 788-790页

作者： ramadan ahmed Mekheimer mohamed Abdallah Ameen Kamal Usef Sadek Chemistry Department Faculty of ScienceEl-Minia UniversityEl-Minia 61519Egypt

Green conditions have been developed for the synthesis of substituted 2-aminothiophenes employing multicomponent reactions of a ketone with active methylene nitrile and elemental sulphur induced by free solar thermal ... 详细信息

关键词： 2-Aminothiophenes Gewald reaction Solar thermal energy

Patterns of liver profile disturbance in patients with COVID-19

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World Journal of Clinical Cases 2022年第7期10卷 2063-2071页

作者： Hend Ibrahim Shousha ahmed ramadan Rania Lithy mohamed El-Kassas Department of Endemic Medicine Faculty of MedicineCairo UniversityCairo 12556Egypt Department of Endemic Medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt

Fever and cough are the most common clinical symptoms of coronavirus disease 2019(COVID-19),but complications(such as pneumonia,respiratory distress syndrome,and multiorgan failure)can occur in people with additional ***-19 may be a new cause of liver disease,as liver profile disturbance is one of the most common findings among *** molecular mechanism underlying this phenomenon,however,is still *** this paper,we review the most current research on the patterns of change in liver profile among patients with COVID-19,the possible explanation for these findings,and the relation to pre-existing liver disease in these patients.

关键词： Liver functions COVID-19 Liver profile Alanine transaminase aspartate transaminase Bilirubin

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

Photovoltaic Models Parameters Estimation Based on Weighted Mean of Vectors

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Computers, Materials & Continua 2023年第3期74卷 5229-5250页

作者： mohamed Elnagi Salah Kamel Abdelhady ramadan mohamed F.Elnaggar Department of Electrical Engineering Faculty of EngineeringAl-Azhar UniversityQena83518Egypt Department of Electrical Engineering Faculty of EngineeringAswan UniversityAswan81542Egypt Department of Electrical Engineering College of EngineeringPrince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia Department of Electrical Power and Machines Engineering Faculty of EngineeringHelwan UniversityHelwan11795Egypt

Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy *** is evident in the advancement of scientific research aimed at improving solar cell *** to the non-linear nature of the photovoltaic cell,modeling solar cells and extracting their parameters is one of the most important challenges in this *** a result,the use of optimization algorithms to solve this problem is expanding and evolving at a rapid *** this paper,a weIghted meaN oF vectOrs algorithm(INFO)that calculates the weighted mean for a set of vectors in the search space has been applied to estimate the parameters of solar cells in an efficient and precise *** each generation,the INFO utilizes three operations to update the vectors’locations:updating rules,vector merging,and local *** INFO is applied to estimate the parameters of static models such as single and double diodes,as well as dynamic models such as integral and fractional *** outcomes of all applications are examined and compared to several recent *** well as the results are evaluated through statistical *** results analyzed supported the proposed algorithm’s efficiency,accuracy,and durability when compared to recent optimization algorithms.

关键词： Photovoltaic(PV)modules weIghted meaN oF vectOrs algorithm(INFO) renewable energy static PV models dynamic PV models solar energy

Ecological risk assessment of surficial sediment by heavy metals from a submerged archaeology harbor,South Mediterranean Sea,Egypt

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Acta Geochimica 2020年第2期39卷 226-235页

作者： Maha ahmed mohamed Abdallah ahmed mohamed Badr-ElDin Marine Pollution Lab National Institute of Oceanography and FisheriesAlexandriaEgypt Oceanography Department Faculty of ScienceAlexandria UniversityAlexandriaEgypt

A protected semi-enclosed embayment,the Eastern Harbor(EH),is situated in the central sector of the Mediterranean coast of Alexandria,*** is a famous fishing dock and water-sport center and its importance arose after the discovery of the Ptolemaic royal quarter of ancient *** protect this national treasure and improve its environmental health,the untreated anthropogenic effluents,which continued for decades into the EH since 1992,must be totally ***,it is an important issue to continually monitor and asses the environmental status of the *** sediment texture,total organic carbon,and the accumulation,distribution,and ecological risks of Cd,Cr,Pb,As,Hg and A1 were determined with a total of 14 surficial sediments samples collected in the EH during *** contents were compared to the literature data to assess the pollution status of *** factors,Degree of contamination(mCd)and potential ecological risk were calculated as a criterion of possible *** mCd calculation produces an overall average value for a range of pollutants,in the present study the contamination factor that provides a measure of the degree of overall contamination in the surface layers in a particular sampling site may provide a better indication of the state of pollution in the EH sediments than other indicators.

关键词： Heavy metals Eastern harbor Enrichment factors Degree of contamination Potential ecological risk