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Nanofluid Flows Within Porous Enclosures Using Non-Linear Boussinesq Approximation

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Computers, materials & Continua 2021年第3期66卷 3195-3213页

作者： Sameh E.Ahmed Dalal Alrowaili Ehab mahmoud mohamed Abdelraheem m.Aly Department of mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia Department of mathematics South Valley UniversityQena83523Egypt mathematics Department College of ScienceJouf UniversitySakakaSaudi Arabia Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Electrical Engineering Department Aswan UniversityAswan81542Egypt

In this paper,the Galerkin finite element method(FEm)together with the characteristic-based split(CBS)scheme are applied to study the case of the non-linear Boussinesq approximation within sinusoidal heating inclined enclosures filled with a non-Darcy porous media and *** enclosure has an inclination angle and its side-walls have varying sinusoidal temperature *** working fluid is a nanofluid that is consisting of water as a based nanofluid and Al2O3 as *** porous medium is modeled using the Brinkman Forchheimer extended Darcy *** obtained results are analyzed over wide ranges of the non-linear Boussinesq parameter 0≤ζ≤1,the phase deviation 00≤Φ≤1800,the inclination angle 00≤γ≤900,the nanoparticles volume fraction 0%≤φ≤4%,the amplitude ratio 0≤a≤1 and the Rayleigh number 104≤Ra≤*** results revealed that the average Nusselt number is enhanced by 0.73%,26.46%and 35.42%at Ra=104,105 and 106,respectively,when the non-linearBoussinesq parameter is varied from 0 to *** addition,rate of heat transfer in the case of a non-uniformly heating is higher than that of a uniformly ***-linear Boussinesq parameter rises the flow speed and heat transfer in an *** deviation makes clear changes on the isotherms and heat transfer rate on the right wall of an *** inclination angle varies the flow speed and it has a slight effect on heat transfer in an enclosure.

关键词： CBS scheme non-linear Boussinesq approximation nonuniformly heating non-darcy flow nanofluid

Preparation of new and novel wave like poly(2-anisidine) zirconium tungstate nanocomposite: Thermal, electrical and ion-selective studies

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Chinese Journal of Chemical Engineering 2019年第2期27卷 459-466页

作者： Anish Khan Aftab Aslam Parwaz Khan mahmoud A.hussein Bernaurdshaw Neppolian Abdullah m.Asiri Chemistry Department King Abdulaziz University Center of Excellence for Advanced materials Research King Abdulaziz University Polymer Chemistry Laboratory Chemistry Department Faculty of Science Assiut University SRm Research Institute SRM University

It is necessary to synthesize new material for the advancements of the technology. In this study, new and novel poly(2-anisidine)@zirconium tungstate(P2A/ZrW_2O_8) was synthesized by simple so-gel method. Physicochemical characterization of P2A/ZrW_2O_8 was done by thermogravimetric analysis(TGA), scanning electron microscopy(SEm), X-ray powder diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), ion exchange and simultaneous four probe dc conductivity studies. The conductivity study revealed its highly semiconducting nature, in the range of 10^(-1)–10^(-2) S·cm^(-1). Ion-exchange capabilities of the composite make it applicable for cation-exchange studies. The result of distribution studies(Kd) revealed its selectivity towards Cd^(2+) compared to other metal ions. This property of the composite was utilized for designing Cd^(2+) selective membrane electrode. Several important physical parameters of the ion-selective electrode were determined, such as Nernstian slope(32.32 mV·decade^(-1)), working ph range was 2.0–4.0 and response time was found ～ 17 *** analytical utility of this wave like composite membrane electrode was as, indicator electrode in various potentiometric titrations.

关键词： Conducting polymers Electrochemistry Ion-exchangers Electrode Cd^2+ Poly(2-anisidine)

Impact of the injected water salinity on oil recovery from sandstone formations:Application in an Egyptian oil reservoir

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Petroleum 2022年第1期8卷 53-65页

作者： m.Fouad Snosy mahmoud Abu El Ela Ahmed El-Banbi helmy Sayyouh General Petroleum Company Egypt Cairo University Egypt The American University in Cairo Egypt

In the last decade,there has been an increasing interest in understanding the effects of changing injected water salinity on the performance of oil *** paper aims to investigate the effects of injected water salinity on oil recovery of an Egyptian oil reservoir(Bahariya formation).An experimental work program has been performed using 25 core plugs and 5 different water salinities to study the effects of changing water salinity during both secondary and tertiary stages of *** objectives of the experimental work were to(1)investigate the effects of the low water salinity on oil recovery and(2)identify the optimum water salinity and the main reservoir parameters for application of low salinity waterflooding project(LSWF)in Bahariya *** results revealed that there is an optimum salinity for waterflooding in the secondary flooding ***,for the tertiary flooding stage,the results showed that the controlling factor is not decreasing the salinity,but rather changing the salinity(*** increasing or decreasing).It was also clear that applying the optimum salinity in the secondary recovery stage is more effective than applying it in the tertiary recovery ***,the results showed that the positive impact of LSWF may be expected in reservoirs with high amount of kaolinite,high values of CEC,and low amounts of plagioclase *** study is an original contribution to develop guidelines for designing optimum salinity waterflooding projects in sandstone reservoirs.

关键词： Low salinity Waterflooding LSWF Sandstone Bahariya formation Western desert

Predicted Oil Recovery Scaling-Law Using Stochastic Gradient Boosting Regression model

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Computers, materials & Continua 2021年第8期68卷 2349-2362页

作者： mohamed F.El-Amin Abdulhamit Subasi mahmoud m.Selim Awad mousa Energy Research Lab. College of EngineeringEffat UniversityJeddah21478KSA Artificial Intelligence and Cyber Security Research Lab. College of EngineeringEffat UniversityJeddah21478KSA Department of mathematics-College of Sciences&humanities in Al Aflaj Prince Sattam bin Abdulaziz UniversityAl-Aflaj11912KSA Department of Physics College of Science&Humanities in Al-AflajPrince Sattam bin Abdulaziz UniversityAl-Aflaj11912KSA mathematics Department Faculty of ScienceAswan UniversityAswan81528Egypt

In the process of oil recovery,experiments are usually carried out on core samples to evaluate the recovery of oil,so the numerical data are fitted into a non-dimensional equation called *** will be essential for determining the behavior of actual *** global non-dimensional time-scale is a parameter for predicting a realistic behavior in the oil field from laboratory *** non-dimensional universal time parameter depends on a set of primary parameters that inherit the properties of the reservoir fluids and rocks and the injection velocity,which dynamics of the *** of the practical machine learning(mL)techniques for regression/classification problems is gradient boosting(GB)*** GB produces a prediction model as an ensemble of weak prediction models that can be done at each iteration by matching a least-squares base-learner with the current *** a randomization process increases the execution speed and accuracy of *** in this study,we developed a stochastic regression model of gradient boosting(SGB)to forecast oil *** nondimensional time-scales have been used to generate data to be used with machine learning *** SGB method has been found to be the best machine learning technique for predicting the non-dimensional time-scale,which depends on oil/rock properties.

关键词： machine learning stochastic gradient boosting linear regression time-scale oil recovery

Assessing effects of deficit irrigation techniques on water productivity of tomato for subsurface drip irrigation system

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International Journal of Agricultural and Biological Engineering 2018年第4期11卷 156-167页

作者： mahmoud S hashem Tarek Zin El-Abedin hussein m Al-Ghobari Agricultural Engineering Department College of Food and Agriculture SciencesKing Saud UniversityRiyadh 11451Saudi Arabia Agricultural Engineering Research Institute(AEnRI) Agricultural Research CenterGizaEgypt Agricultural Engineering Department College of AgricultureAlexandria UniversityAlexandriaEgypt

Water resources are subjected to ever-increasing supply constraints due to extensive agricultural water demand for irrigated ***,water-saving irrigation strategies need to be *** present study was conducted to explore the possibilities of using regulated deficit irrigation(RDI)and partial root zone drying irrigation(PRD)methods as water-saving irrigation techniques for subsurface *** objective of this study are to assess the effects of RDI and PRD irrigation on the water productivity of vegetable crops(tomato)under SSD systems in arid climatic conditions,and to compare the responses of tomato crops to PRD,RDI,and FI under an SSD system in terms of productivity,crop quality,and the amount of water *** field experiment was conducted during the fall 2014-2015 and 2015-2016 seasons in an experimental field located on an educational farm owned by the Faculty of Food and Agriculture Sciences Department,King Saud University,Riyadh,Kingdom of Saudi *** area of 102.7 m^(2)(13 m×7.9 m)was allocated for the experiment to manage three treatments:RDI,PRD,and full irrigation(FI).The RDI and PRD treatments received 70%of the irrigation water volume of *** was replicated three *** most important results indicated that the soil water content(SWC)for the RDI and PRD treatments was lower than that of the FI *** had the highest stomatal conductance values(gs),while PRD had the lowest stomatal conductance *** photosynthetic rate(A_(n))was lower under RDI and PRD compared to ***,there was no significant change in A_(n) between treatments for most readings taken during both time periods,which means that the water saving treatments(PRD and RDI)did not affect the net photosynthesis rate,thereby enhancing irrigation water use efficiency(IWUE)under DI *** water-saving irrigation techniques decreased transpiration rate(T)compared to the FI *** values of the abscisic acid(ABA)contents were higher

关键词： full irrigation(FI) regulated deficit irrigation(RDI) partial root zone drying(PRD) irrigation water use efficiency(IWUE)

Encephalitis Detection from EEG Fuzzy Density-Based Clustering model with multiple Centroid

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Intelligent Automation & Soft Computing 2023年第3期35卷 3129-3140页

作者： hanan Abdullah mengash Alaaeldin m.hafez hanan A.hosni mahmoud Department of Information Systems College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Information Systems College of Computer and Information SciencesKing Saud UniversityRiyadhSaudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia

Encephalitis is a brain inﬂammation *** can yield to seizures,motor disability,or some loss of vision or ***,encepha-litis can be a life-threatening and proper diagnosis in an early stage is very ***,in this paper,we are proposing a deep learning model for computerized detection of Encephalitis from the electroencephalogram data(EEG).Also,we propose a Density-Based Clustering model to classify the distinctive waves of *** clustering models usually employ a computed single centroid virtual point to deﬁne the cluster conﬁguration,but this single point does not contain adequate *** precisely extract accurate inner structural data,a multiple centroids approach is employed and deﬁned in this paper,which deﬁnes the cluster conﬁguration by allocating weights to each state in the *** multiple EEG view fuzzy learning approach incorporates data from every sin-gle view to enhance the model's clustering *** a fuzzy Density-Based Clustering model with multiple centroids(FDBC)is *** model employs multiple real state centroids to deﬁne clusters using Partitioning Around Centroids *** Experimental results validate the medical importance of the proposed clustering model.

关键词： Density clustering clustering structural data fuzzy set

Investigation of soliton solutions with different wave structures to the(2+1)-dimensional heisenberg ferromagnetic spin chain equation

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Communications in Theoretical Physics 2020年第3期72卷 7-13页

作者： m S Osman K U Tariq Ahmet Bekir A Elmoasry Nasser S Elazab m Younis mahmoud Abdel-Aty Department of mathematics Faculty of ScienceCairo UniversityGizaEgypt Department of mathematics Faculty of Applied ScienceUmm Alqura UniversityMakkah 21955Saudi Arabia School of mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Department of mathematics Mirpur University of Science and TechnologyMirpur(AJK)10250Pakistan Neighbourhood of Akcaglan Imarli StreetNumber:28/426030EskisehirTurkey mathematics department College of ScienceMajmaah UniversitySaudi Arabia Punjab University College of Information Technology University of the PunjabLahore 54590Pakistan Department of mathematics Faculty of ScienceSohag UniversitySohagEgypt Applied Science University Bahrain

The principal objective of this article is to construct new and further exact soliton solutions of the(2+1)-dimensional heisenberg ferromagnetic spin chain equation which investigates the nonlinear dynamics of magnets and explains their ordering in ferromagnetic *** solutions are exerted via the new extended FAN sub-equation *** successfully obtain dark,bright,combined bright-dark,combined dark-singular,periodic,periodic singular,and elliptic wave solutions to this equation which are interesting classes of nonlinear excitation presenting spin dynamics in classical and semi-classical continuum heisenberg systems.3D figures are illustrated under an appropriate selection of *** applied technique is suitable to be used in gaining the exact solutions of most nonlinear partial/fractional differential equations which appear in complex phenomena.

关键词： soliton solutions heisenberg ferromagnetic equation FAN sub-equation method

Influence of proton pump inhibitors on gastritis diagnosis and pathologic gastric changes

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World Journal of Gastroenterology 2015年第15期21卷 4599-4606页

作者： Soumana C Nasser mahmoud Slim Jeanette G Nassif Selim m Nasser School of Pharmacy Lebanese American University Institute of Neuroscience University of Granada Department of Pathology School of Medicine Lebanese American University

AIm: To investigate the influence of proton pump inhibitors(PPIs) exposure on the diagnosis of helicobacter pylori(h. pylori) gastritis and intestinal ***: Chronic PPI use is associated with masking of h. pylori infection. Patients with h. pylori infection are predisposed to gastric and duodenal ulcers, and long-term infection with this organism has been associated with gastric mucosal atrophy and serious long-term complications, such as gastric lymphoma and adenocarcinoma. Three hundred patients diagnosed with gastritis between January 2008 and April 2010 were included in our study. The computerized medical database of these patients was reviewed retrospectively in order to assess whether the type of gastritis diagnosed(h. pylori vs non-h. pylori gastritis) is influenced by PPI exposure. h. pylori density was graded as low, if corresponding to mild density following the Updated Sydney System, or high, if corresponding to moderate or severe densities in the Updated Sydney ***: Patients were equally distributed between males and females with a median age at the time of diagnosis of 50 years old(range: 20-87). The histological types of gastritis were classified as h. pylori gastritis(n = 156, 52%) and non-h. pylori gastritis(n = 144, 48%). All patients with non-h. pylori gastritis had inactive chronic gastritis. Patients with no previous PPI exposure were more likely to be diagnosed with h. pylori gastritis than those with previous PPI exposure(71% vs 34.2%, P metaplasiawas more likely to be detected in the latter patients(1.4% vs 6.5%, P = 0.023). multivariate analysis has also demonstrated that in the presence of previous PPI exposure(OR = 0.217, 95%CI: 0.123-0.385), GERD(OR = 0.317, 95%CI: 0.132-0.763, P = 0.01), alcohol intake(OR = 0.396, 95%CI: 0.195-0.804, P = 0.01), the detection of h. pylori was less likely. Chronic use of PPIs may mask h. pylori infections promoting the diagnosis of non-h. pylori gastritis and le

关键词： Gastritis Diagnosis helicobacter pylori Proton pump inhibitors Social factors

Q-Switching Pulse Operation in 1.5-μm Region Using Copper Nanoparticles as Saturable Absorber

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Chinese Physics Letters 2017年第3期34卷 41-44页

作者： A.R.muhammad m.T.Ahmad R.Zakaria h.R.A.Rahim S.F.A.Z.Yusoff K.S.hamdan h.h.m.Yusof h.Arof S.W.harun Department of Electrical Engineering Faculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia Photonics Research Centre Physics DepartmentFaculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia

We demonstrate a passively Q-switched erbium-doped fiber laser （EDFL） using a copper nanoparticle （CuNP） thin film as the saturable absorber in a ring cavity. A stable Q-switched pulse operation is observed as the CuNP saturable absorber （SA） is introduced in the cavity. The pulse repetition rate of the EDFL is observed to be proportional to the pump power, and is limited to 101.2khz by the maximum pump power of 113.7mW. On the other hand, the pulse width reduces from 10.19μs to 4.28μs as the pump power is varied from 26.1 mW to 113.7mW. The findings suggest that CuNP SA could be useful as a potential saturable absorber for the development of the robust, compact, efficient and low cost Q-switched fiber laser operating at 1.5-μm region.

关键词： Cu m Region Using Copper Nanoparticles as Saturable Absorber Q-Switching Pulse Operation in 1.5 SA khz EDF