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A Comparative Study of Adomian Decomposition Method with Variational Iteration Method for Solving Linear and Nonlinear Differential Equations

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Journal of Applied Mathematics and Physics 2024年第8期12卷 2789-2819页

作者： Sarah Khaled Al baghdadi N. Ameer Ahammad General Studies Department Technical and Vocational Training Corporation Tabuk KSA Department of Mathematics Faculty of Science University of Tabuk Tabuk KSA

This study compares the Adomian Decomposition Method (ADM) and the Variational Iteration Method (VIM) for solving nonlinear differential equations in engineering. Differential equations are essential for modeling dynamic systems in various disciplines, including biological processes, heat transfer, and control systems. This study addresses first, second, and third-order nonlinear differential equations using Mathematica for data generation and graphing. The ADM, developed by George Adomian, uses Adomian polynomials to handle nonlinear terms, which can be computationally intensive. In contrast, VIM, developed by He, directly iterates the correction functional, providing a more straightforward and efficient approach. This study highlights VIM’s rapid convergence and effectiveness of VIM, particularly for nonlinear problems, where it simplifies calculations and offers direct solutions without polynomial derivation. The results demonstrate VIM’s superior efficiency and rapid convergence of VIM compared with ADM. The VIM’s minimal computational requirements make it practical for real-time applications and complex system modeling. Our findings align with those of previous research, confirming VIM’s efficiency of VIM in various engineering applications. This study emphasizes the importance of selecting appropriate methods based on specific problem requirements. While ADM is valuable for certain nonlinearities, VIM’s approach is ideal for many engineering scenarios. Future research should explore broader applications and hybrid methods to enhance the solution’s accuracy and efficiency. This comprehensive comparison provides valuable guidance for selecting effective numerical methods for differential equations in engineering.

关键词： Differential Equations Numerical Analysis Mathematical Computing Engineering Models Nonlinear Dynamics

Hepatobiliary manifestations following two-stages elective laparoscopic restorative proctocolectomy for patients with ulcerative colitis:A prospective observational study

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World Journal of Gastrointestinal Surgery 2023年第2期15卷 234-248页

作者： Tamer A A M Habeeb Abdulzahra Hussain Mauro Podda Pasquale Cianci Bruce Ramshaw Khaled Safwat Wesam M Amr Tamer Wasefy Alaa A Fiad Mohamed Ibrahim Mansour Adel Mahmoud Moursi GamalOsman Anass Qasem Mohamed Fawzy Mohamed Ibrahim Abo Alsaad Abd-Elfattah Kalmoush MohammedShaaban Nassar Fawzy M Mustafa Mahmoud Hassib Morsi Badawy Ahmed Hamdy Hamdi Elbelkasi Bassam Mousa Abd-Elrahman M Metwalli Walid A Mawla Mostafa M Elaidy muhammad Ali baghdadi Ahmed Raafat Department of General Surgery Faculty of MedicineZagazig UniversityZagazig 44759SharkiaEgypt Homerton University Hospital London E96SRUK Department of Surgical Science University of CagliariCagliari 2432Italy Department of Medical and Surgical Sciences Universitàdegli studi di FoggiaFoggia 546Italy MD CQInsights PBC Co-founder&CEOTennesseeTN 37010United States Department of Internal Medicine Zagazig UniversityZagazig 2355Egypt Department of Internal Medicine Suez UniversitySuez 235Egypt Department of General Surgery Faculty of Medicine-Merit UniversitySohag 82511Egypt Department of General Surgery Al-azhar UniversityCairo 285Egypt Department of Hepato-Bilio-Pancreatic(HBP)Surgery National Hepatology and Tropical Medicine Research InstituteCairo 285Egypt Department of General Surgery Mataryia Teaching HospitalCairo 285Egypt

BACKGROUND Hepatobiliary manifestations occur in ulcerative colitis(UC)*** effect of laparoscopic restorative proctocolectomy(LRP)with ileal pouch anal anastomosis(IPAA)on hepatobiliary manifestations is *** To evaluate hepatobiliary changes after two-stages elective laparoscopic restorative proctocolectomy for patients with *** Between June 2013 and June 2018,167 patients with hepatobiliary symptoms underwent two-stage elective LRP for UC in a prospective observational *** with UC and having at least one hepatobiliary manifestation who underwent LRP with IPAA were included in the *** patients were followed up for four years to assess the outcomes of hepatobiliary *** The patients'mean age was 36±8 years,and males predominated(67.1%).The most common hepatobiliary diagnostic method was liver biopsy(85.6%),followed by Magnetic resonance cholangiopancreatography(63.5%),Antineutrophil cytoplasmic antibodies(62.5%),abdominal ultrasonography(35.9%),and Endoscopic retrograde cholangiopancreatography(6%).The most common hepatobiliary symptom was Primary sclerosing cholangitis(PSC)(62.3%),followed by fatty liver(16.8%)and gallbladder stone(10.2%).66.4%of patients showed a stable course after *** or regressive courses occurred in 16.8%of *** was 6%,and recurrence or progression of symptoms required surgery for 15%.Most PSC patients(87.5%)had a stable course,and only 12.5%became ***-thirds(64.3%)of fatty liver patients showed a regressive course,while one-third(35.7%)showed a stable *** rates were 98.8%,97%,95.8%,and 94%at 12 mo,24 mo,36 mo,and at the end of the *** In patients with UC who had LRP,there is a positive impact on hepatobiliary *** caused an improvement in PSC and fatty liver *** most prevalent unchanged course was PSC,while the most common improvement was fatty liver disease.

关键词： Courses Hepatobiliary manifestations Primary sclerosing cholangitis Restorative proctocolectomy

Some Factorization Properties in A+B[Г^(*)]Domains

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Algebra Colloquium 2020年第3期27卷 643-650页

作者： E.Boulayat S.El baghdadi Department of Mathematics Beni Mellal University FSTP.O.Box 523Beni MellalMorocco

Let A■B be an extension of integral domains andГa commutative,additive,cancellative,torsion-free monoid with T∩-Г={0}.Let B[Г]be the semigroup ring ofГover B and setГ^(*)=Г\{0}.Then R=A+B[Г^(*)]is a subring of B[Г].We investigate various factorization properties which are weaker than unique factorization in the domainsof the form A+B[Г^(*)].

关键词： monoid factorization atomic ACCP BFD

Optimization study of a PEM fuel cell performance using 3D multi-phase computational fluid dynamics model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 285-300页

作者： AL-baghdadi Maher A.R. Sadiq AL-JANABI Haroun A.K.Shahad Department of Mechanical Engineering International Technological University

An optimization study using a comprehensive 3D, multi-phase, non-isothermal model of a PEM （proton exchange membrane） fuel cell that incorporates significant physical processes and key parameters affecting fuel cell performance is presented and discussed in detail. The model accounts for both gas and liquid phase in the same computational domain, and thus allows for the implementation of phase change inside the gas diffusion layers. The model includes the transport of gaseous species, liquid water, protons, energy, and water dissolved in the ion-conducting polymer. Water is assumed to be exchanged among three phases： liquid, vapottr, and dissolved, with equilibrium among these phases being assumed. This model also takes into account convection and diffusion of different species in the channels as well as in the porous gas diffusion layer, heat transfer in the solids as well as in the gases, and electrochemical reactions. The results showed that the present multi-phase model is capable of identifying important parameters for the wetting behaviour of the gas diffusion layers and can be used to identify conditions that might lead to the onset of pore plugging, which has a detrimental effect on the fuel cell performance. This model is used to study the effects of several operating, design, and material parameters on fuel cell performance. Detailed analyses of the fuel cell performance under various operating conditions have been conducted and examined.

关键词： Optimization PEM fuel cell Multi-phase Water transport CFD (computational fluid dynamics)

Effect of intermetallic compounds on the fracture behavior of dissimilar friction stir welding joints of Mg and Al alloys

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International Journal of Minerals,Metallurgy and Materials 2019年第10期26卷 1285-1298页

作者： Amir Hossein baghdadi Zainuddin Sajuri Nor Fazilah Mohamad Selamat Mohd Zaidi Omar Yukio Miyashita Amir Hossein Kokabi Centre for Materials Engineering and Smart Manufacturing Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600 UKM BangiSelangor 43600Malaysia Department of Mechanical Engineering Nagaoka University of TechnologyNagaoka940-2188Japan Department of Materials Science and Engineering Sharif University of TechnologyTehran 11365-11155Iran

Joining Mg to Al is challenging because of the deterioration of mechanical properties caused by the formation of intermetallic compounds(IMCs) at the Mg/Al interface. This study aims to improve the mechanical properties of welded samples by preventing the fracture location at the Mg/Al interface. Friction stir welding was performed to join Mg to Al at different rotational and travel speeds. The microstructure of the welded samples showed the IMCs layers containing Al12Mg17(γ) and Al3Mg2(β) at the welding zone with a thickness(< 3.5 μm). Mechanical properties were mainly affected by the thickness of the IMCs, which was governed by welding parameters. The highest tensile strength was obtained at 600 r/min and 40 mm/min with a welding efficiency of 80%. The specimens could fracture along the boundary at the thermo-mechanically affected zone in the Mg side of the welded joint.

关键词： aluminum alloy magnesium alloy intermetallic compounds dissimilar welded joint friction stir welding

Assessment of spatial and seasonal water quality variation of Oum Er Rbia River(Morocco)using multivariate statistical techniques

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International Soil and Water Conservation Research 2016年第4期4卷 284-292页

作者： Ahmed Barakat Mohamed El baghdadi Jamila Rais Brahim Aghezzaf Mohamed Slassi Georessources and Environment Laboratory Sultan My Slimane UniversityBéni-Mellal 23000Morocco Hydraulic Basin Agency of Oum Er Rbia(ABHOER) Béni-Mellal 23000Morocco

The aim of this study is to assess the spatial and temporal water quality variation and to determine the main contamination sources in the Oum Er Rbia River and its main tributary,El Abid *** water quality data were collected during 2000-2012 from fourteen sampling stations distributed along the *** water quality indicators used were TEMP,pH,EC,turbidity,TSS,DO,NH_(4)^(+),NH_(3)^(-),TP,BOD5,COD and *** water quality data was analyzed using multivariate statistical methods including Pearson's correlation,PCA,and *** results showed that in some stations the water quality parameters were over Moroccan water *** applied to compare the compositional patterns among the analyzed water samples,identified and four factors accounting for almost 63% of the total variation in the *** suggests that the variations in water compounds’concentration are mainly related to point source contamination(domestic and industrial wastewater),non-point source contamination(agriculture activities),as well as natural processes(weathering of soil and rock).CA showed relatively spatial and seasonal changes in surface water quality,which are usually indicators of contamination with rainfalls or other ***,this study showed that the water was potentially hazardous to health of the consumers and highlighted the need to treat industrial and municipal wastewater and to encourage sustainable agricultural practices to prevent adverse health *** therefore suggest wise management of anthropogenic activities in the catchment of Oum Er Bia River and their tributaries.

关键词： Oum Er Rbia basin Temporal/spatial assessment Water quality Multivariate statistics

Microstructural evolution,dislocation density and tensile properties of Al–6.5Si–2.1Cu–0.35Mg alloy produced by different casting processes

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Journal of Materials Science & Technology 2021年第36期95卷 145-157页

作者： S.Samat M.Z.Omar A.H.baghdadi I.F.Mohamed A.Rajabi A.M.Aziz Department of Mechanical and Manufacturing Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangiUKM 43600Malaysia

Al–Si–Cu–Mg foundry alloys are used in casting process ***,their strength properties remain low due to their microstructural characteristics and *** this work,the microstructural characteristics,dislocation densities,and mechanical properties of Al–Si–Cu–Mg cast alloys prepared through different casting methods were studied *** casting processes,namely,gravity casting(GC),rheocasting(RC),thixoforming(Thixo),and Thixo with heat treatment,were *** GC and RC samples had mainly dendriticα-Al phase microstructures and exhibited coarse Si particles and intermetallic compounds in their interdendritic *** contrast,the Thixo and heat-treated Thixo(HT-Thixo)samples exhibited microstructural refinement with uniformly distributedα-Al globules,fine fibrous Si particles,and fragmented intermetallic compounds amongα-Al *** accumulation of dislocation densities increased in the Thixo sample as the strain was increased due to plastic ***,the ultimate tensile strength and yield strength of the HT-Thixo sample increased by 87%and 63%,respectively,relative to those of the GC *** cleavage fracture displayed by the GC and RC samples led to brittle ***,the Thixo and HT-Thixo samples presented dimple-based ductile fracture.

关键词： Al–Si–Cu–Mg alloy Thixoforming Microstructure Mechanical property Dislocation density

Contribution of Geographic Information Systems for the Management of Water Resources： Case of Groundwater Resources of the Plain of Mascara （Algeria）

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Journal of Earth Science and Engineering 2014年第4期4卷 245-255页

作者： baghdadi Boukerma Laboratory of Hydrology and Management of Water Resources University of Sciences and Technology Oran 31000 Algeria

The plain of Mascara includes groundwater resources, heavily exploited for the needs of the population, industry and agriculture. However, this resource is under threat from the point of view of quality and quantity. The degradation of water quality comes from water discharges untreated （domestic and/or industrial） and from the irrational use of fertilizers and pesticides in agriculture. The decrease in reserves is due to the effects of intensive exploitation. Several studies on the water resources of the plain generated a mass of very important data. In most cases, these data are disparate at different institutions managers （water resources, environment, etc.）, and are found recorded in paper documents, difficult to exploit. For this reason, it would be essential to use reliable new techniques, namely the GIS （geographic information systems）. The implementation of the GIS of the plain of Mascara （with extension to all the sub-basin of Wadi Fekan） must permit to organize the data and transform it into information. Integration, crossing and superposition of the data with other variables may contribute to spatial analysis and generate very important thematic maps. The GIS constitutes a very effective decision aid tool for the management, exploitation, preservation and protection of water resources. The exploitation possibilities of GIS are multiple, direct or indirect. We give an example as the coupling with a groundwater flow model that may be the subject of additional work.

关键词： Management resources water geographic information systems Mascara.

Sickle cell nephropathy:A review of novel biomarkers and their potential roles in early detection of renal involvement

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World Journal of Clinical Pediatrics 2022年第1期11卷 14-26页

作者： Osama Y Safdar Rana M baghdadi Sereen A Alahmadi Bana E Fakieh Amaal M Algaydi of Pediatric King Abdulaziz UniversityJEDDAH 21414Saudi Arabia College of Medicine King Abdulaziz UniversityJEDDAH 21422Saudi Arabia

Whether the underlying mutations are homozygous,heterozygous,or coinherited with other hemoglobinopathies,sickle cell disease is known to afflict the kidneys,leading to the clinical entity known as sickle cell nephropathy(SCN).Although common,SCN remains diagnostically *** studies performed in the context of renal disorders often fail to detect early stage *** makes the quest for early diagnosis and treatment more challenging,and it increases the burden of chronic kidney disease-related morbidity among *** diagnostic tools have been employed to overcome this *** this study,we discuss various biomarkers of SCN,including those employed in clinical practice and others recently identified in experimental settings,such as markers of vascular injury,endothelial dysfunction,tubulo-glomerular damage,and oxidative *** include kidney injury molecule-1,monocyte chemoattractant protein-1,N-acetyl-B-D-glucosaminidase,ceruloplasmin,orosomucoid,nephrin,and cation channels,among ***,we explore the potential of novel biomarkers for refining diagnostic and therapeutic approaches and describe some obstacles that still need to be *** highlight the importance of a collaborative approach to standardize the use of promising new ***,we outline the limitations of conventional markers of renal damage as extensions of the pathogenic process occurring at the level of the organ and its functional subunits,with a discussion of the expected pattern of clinical and biochemical progression among patients with SCN.

关键词： Sickle cell disease Sickle cell nephropathy Chronic kidney disease Kidney injury molecule-1 Monocyte chemoattractant protein-1 N-acetyl-B-D-glucosaminidase