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Effects of variable properties on MHD heat and mass transfer flow near a stagnation point towards a stretching sheet in a porous medium with thermal radiation

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Chinese Physics B 2012年第5期21卷 353-363页

作者： A.M.salem Rania Fathy Department of Basic Science Faculty of Computer&InformaticsSuez Canal University Department of Mathematics Faculty of ScienceZagazig University

The effect of variable viscosity and thermal conductivity on steady magnetohydrodynamic（MHD） heat and mass transfer flow of viscous and incompressible fluid near a stagnation point towards a permeable stretching sheet embedded in a porous medium are presented,taking into account thermal radiation and internal heat genberation/*** stretching velocity and the ambient fluid velocity are assumed to vary linearly with the distance from the stagnation *** Rosseland approximation is used to describe the radiative heat flux in the energy *** governing fundamental equations are first transformed into a system of ordinary differential equations using a scaling group of transformations and are solved numerically by using the fourth-order Rung-Kutta method with the shooting technique.A comparison with previously published work has been carried out and the results are found to be in good *** results are analyzed for the effect of different physical parameters,such as the variable viscosity and thermal conductivity,the ratio of free stream velocity to stretching velocity,the magnetic field,the porosity,the radiation and suction/injection on the flow,and the heat and mass transfer *** results indicate that the inclusion of variable viscosity and thermal conductivity into the fluids of light and medium molecular weight is able to change the boundary-layer behavior for all values of the velocity ratio parameter λ except for λ = *** addition,the imposition of fluid suction increases both the rate of heat and mass transfer,whereas fluid injection shows the opposite effect.

关键词： variable viscosity variable thermal conductivity stagnation point

Urinary incontinence among Jordanian women:Prevalence,types,and associated factors

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Asian Journal of Urology 2024年第4期11卷 651-659页

作者： Ismaiel Abu Mahfouz Marco H.Blanker Fida Asali Lama al Mehaisen Hamza al-Amoosh salem Abu Mahfouz Department of Obstetrics and Gynaecology Faculty of MedicineAl-Balqa Applied UniversityAl SaltJordan Department of Primary and Longterm Care University Medical Center GroningenUniversity of GroningenGroningenthe Netherlands Department of Obstetrics and Gynaecology Faculty of MedicineThe Hashemite UniversityZarkaJordan

ObjectiveUrinary incontinence (UI) is a prevalent condition with a negative impact on women's quality of life. Data about UI among Jordanian women are lacking;therefore, we aimed to investigate the prevalence, types, and associated *** cross sectional nationwide survey was conducted between 1 March 2020 and 15 April 2020. Women were included if they were 18 years of age or more and had access to the internet. Data collected included women's characteristics, UI types, and associated factors. UI was inventoried by asking women if they have UI (yes/no), and the Arabic language validated International Consultation on Incontinence Questionnaire Urinary Incontinence-Short Form was used. Age-group specific prevalence rates of UI were estimated, and associated factors were studied using logistic regression *** from 2118 women were analysed. The median age was 40 (range 18–85) years;58.3% gave birth three or more times;and 64.1% consistently reported having UI. Limited mobility and being multiparous increased the likelihood of reporting UI. Compared to women with normal body mass index, overweight and obese women were 1.9 times and 4.4 times more likely to report UI, *** prevalence of UI among Jordanian women is 64.1%, with mixed UI and stress UI being the more prevalent types in women younger than 60 years old. Age, parity body mass index, and limited mobility are all associated factors with UI. The results of this study provide healthcare policy makers with the necessary information to increase awareness and knowledge regarding UI.

关键词： Urinary incontinence Prevalence Stress urinary incontinence Urge urinary incontinence Association

FRACTIONal ORDER BOUNDARY ValUE PROBLEM WITH INTEGRal BOUNDARY CONDITIONS INVOLVING PETTIS INTEGRal

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Acta Mathematica Scientia 2011年第2期31卷 661-672页

作者： Hussein A.H. salem Department of Mathematics Faculty of Sciences Alexandria University Department of Mathematics Faculty of Sciences and Arts Taibah University

In this article, we investigate the existence of Pseudo solutions for some fractional order boundary value problem with integral boundary conditions in the Banach space of continuous function equipped with its weak topology. The class of such problems constitute a very interesting and important class of problems. They include two, three, multi-point and nonlocal boundary-value problems as special cases. In our investigation, the right hand side of the above problem is assumed to be Pettis integrable function. To encompass the full scope of this article, we give an example illustrating the main result.

关键词： Fractional calculus Pseudo solution boundary value problem Pettis integrals

Numerical Simulation of Dual-Phase-Lag Model and Inverse Fractional Single-Phase-Lag Problem for the Non-Fourier Heat Conduction in a Straight Fin

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Journal of Thermal Science 2020年第3期29卷 632-646页

作者： MOZAFARIFARD Milad AZIMI Aziz MEHRZAD salem Department of Mechanical Engineering Shahid Chamran University of AhvazAhvaz ***Iran

In recent years,many studies have been done on heat transfer in the fin under unsteady boundary conditions using Fourier and non-Fourier *** this paper,unsteady non-Fourier heat transfer in a straight fin having an internal heat source under periodic temperature at the base was investigated by solving numerically Dual-Phase-Lag and Fractional Single-Phase-Lag *** this way,the governing equations of these models were presented for heat conduction analysis in the fin,and their results of the temperature distribution were validated using the theoretical results of Single and Dual-Phase-Lag *** that,for the first time the order of fractional derivation and heat flux relaxation time of the fractional model were obtained for the straight fin problem under periodic temperature at the base using Levenberg-Marquardt parameter estimation *** solve the inverse fractional heat conduction problem,the numerical results of Dual-Phase-Lag model were used as the *** results obtained from Fractional Single-Phase-Lag model could predict the fin temperature distribution at unsteady boundary condition at the base as well as the Dual-Phase-Lag model could.

关键词： non-Fourier heat transfer fractional calculus inverse heat transfer Levenberg-Marquardt straight fin unsteady boundary condition

Metamaterial-Based Compact Antenna with Defected Ground Structure for 5G and Beyond

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Computers, Materials & Continua 2022年第5期71卷 2383-2399页

作者： Md.Mushfiqur Rahman Md.Shabiul Islam Mohammad Tariqul Islam Samir salem al-Bawri Wong Hin Yong Faculty of Engineering Multimedia UniversityPersiaran MultimediaCyberjaya63100SelangorMalaysia Department of Electrical Electronic and Systems EngineeringFaculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangi43600Malaysia Space Science Centre Climate Change InstituteUniversiti Kebangsaan Malaysia(UKM)Bangi43600Malaysia

In this paper,a unit cell of a single-negative metamaterial structure loaded with a meander line and defected ground structure(DGS)is investigated as the principle radiating element of an *** unit cell antenna causes even or odd mode resonances similar to the unit cell structure depending on the orientation of the microstrip feed used to excite the unit ***,the orientation which gives low-frequency resonance is considered *** unit cell antenna is then loaded with a meander line which is parallel to the split bearing side and connects the other two sides orthogonal to the split bearing *** modified structure excites another mode of resonance at high frequency when a meander line defect is loaded on the metallic ground *** parameters of the meander line structure,the DGS shape,and the unit cell are optimized to place these two resonances at different frequencies with proper frequency intervals to enhance the ***,the feed is placed in an offset position for better impedance matching without affecting the bandwidth The compact dimension of the antenna is 0.25λL×0.23λL×0.02λL,whereλL is the free space wavelength with respect to the center frequency of the impedance *** proposed antenna is fabricated and *** results reveal that the modified design gives monopole like radiation patterns which achieves a fractional operating bandwidth of 26.6%,from 3.26 to 4.26 GHz for|S11|al plane.

关键词： Split ring resonator(SRR) meander line defected ground structure compact antenna bandwidth enhancement 5G technology

A Novel Method for Routing Optimization in Software-Defined Networks

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Computers, Materials & Continua 2022年第12期73卷 6393-6405页

作者： salem alkhalaf Fahad alturise Department of Computer College of Science and Arts in ArRass Qassim UniversityAr RassQassimSaudi Arabia

Software-defined network(SDN)is a new form of network architecture that has programmability,ease of use,centralized control,and protocol *** has received high attention since its *** SDN network architecture,network management becomes more efficient,and programmable interfaces make network operations more flexible and can meet the different needs of various *** mainstream communication protocol of SDN is OpenFlow,which contains aMatch Field in the flow table structure of the protocol,which matches the content of the packet header of the data received by the switch,and completes the corresponding actions according to the matching results,getting rid of the dependence on the protocol to avoid designing a new *** order to effectively optimize the routing forSDN,this paper proposes a novel algorithm based on reinforcement *** proposed technique canmaximize numerous objectives to dynamically update the routing strategy,and it has great generality and is not reliant on any specific network *** control of routing strategy is more complicated than many Q-learning-based algorithms due to the employment of reinforcement *** performance of the method is tested by experiments using the OMNe++*** experimental results reveal that our PPO-based SDN routing control method has superior performance and stability than existing algorithms.

关键词： Reinforcement learning routing algorithm software-defined network optimization

Sickle cell cholangiopathy:An endoscopic retrograde cholangiopancreatography evaluation

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World Journal of Gastroenterology 2009年第42期15卷 5316-5320页

作者： Hussain Issa ali al-Haddad Ahmed al-salem Department of Internal Medicine Division of GastroenterologyKing Fahad Specialist HospitalDammam 31444Saudi Arabia Department of Internal Medicine Qatif Central HospitalQatif 31911Saudi Arabia Department of Pediatric Surgery Maternity and Children HospitalDammamQatif 31911Saudi Arabia

AIM:To evaluate the role of endoscopic retrograde cholangiopancreatography(ERCP) in patients with sickle cell disease(SCD) .METHODS:Two hundred and twenty four SCD patients with cholestatic jaundice(CJ) had *** indications for ERCP were based on clinical and biochemical evidence of CJ and ultrasound ***:Two hundred and forty ERCPs were *** indications for ERCP were:CJ only in 79,CJ and dilated bile ducts without stones in 103,and CJ and bile duct stones in *** those with CJ only,ERCP was normal in 42(53.2%) ,and 13(16.5%) had dilated bile ducts without an obstructive *** the remaining 22,there were bile duct stones with or without *** those with CJ,dilated bile ducts and no stones,ERCP was normal in 17(16.5%) ,and 28(27.2%) had dilated bile ducts without an obstructive *** the remaining 58,there were bile ducts stones with or without *** those with CJ and bile duct stones,ERCP was normal in two(4.8%) ,and 14(33.3%) had dilated bile ducts without an obstructive *** the remaining 26,there were bile duct stones with or without ***:Considering the high frequency of biliary sludge and bile duct stones in SCD,endoscopic sphincterotomy might prove helpful in these patients.

关键词： Sickle cell disease Hepatobiliary Cholestsatic jaundice Sickle cell hepatopathy Sickle cell cholangiopathy Endoscopic retrograde cholangiopancreatography

Tribological Investigation of HDPE-cuttlebone and HDPE-red Coral Composites

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Journal of Bionic Engineering 2019年第6期16卷 1068-1079页

作者： Amira salem Walid Bensalah Salah Mezlini Universite de Monastir Ecole Nationale d'Ingenieurs de Monastir(ENIM)Laboratoire de Genie Mecanique(LGM)LR99ES325019MonastirTunisia

In this paper,the tribological properties of cuttlebone(CB)-reinforced high density polyethylene(HDPE)and Red Coral(RC)-reinfbrced HDPE composites were *** composite specimens were prepared with a hot compression molding machine using different weight proportions of fillers blended with *** tribological behavior of the composite disks was studied using pin-on-disk tribometer under dry condition against stainless steel M30NW *** coefficient of friction as well as wear rate were examined to study the effects of the two fillers on the tribological perfonnance of both *** wear tests,different composites were examined using a Scanning Electron Microscope(SEM).It was fbund that the use of cuttlebone(CB)and Red Coral(RC)as reinforcement improved the tribological properties of HDPE.

关键词： cuttlebone-reinforced HDPE red coral-reinforced HDPE wear rate friction coefficient wear mechanism

N-methyl-2-pyrrolidonium-based Br?nsted-Lewis acidic ionic liquids as catalysts for the hydrolysis of cellulose

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Science China Chemistry 2016年第5期59卷 564-570页

作者： Zheng Zhao Na Li Abdul Waheed Bhutto Ahmed A. Abdeltawab salem S. al-Deyab Guangqing Liu Xiaochun Chen Guangren Yu Beijing Key Laboratory of Membrane Science and Technology College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Department of Chemical Engineering Mehran University of Engineering and TechnologyJamshoro 76062Pakistan Petrochemicals Research Chair College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

We experimentally studied the catalytic performances of a series of Brrnsted-Lewis acidic N-methyl-2-pyrrolidonium metal chlorides （[Hnmp]Cl/MClx, where M=Fe, Zn, A1, or Cu） for the hydrolysis of microcrystalline cellulose （MCC） and cotton to produce reducing sugar. A variety of factors, such as temperature, time, ionic liquid （IL） species, IL dosage, and the concentra- tion of the metal chloride were investigated. [Hnmp]Cl/FeCl3 presented the best hydrolysis performance, affording a 98.8% yield of total reducing sugar from MCC （1 h, 100 ℃, 0.1 g MCC, 0.2 g acidic IL, 2.0 g [Bmim]Cl as solvent）, which is better than or comparable to results previously obtained with other -SO3H functionalized acidic ILs. The hydrolysis performances of [Hnmp]Cl/MClx were rationalized using density functional theory calculations, which indicated that interactions between the metal chlorides and the cellulose, including charge-transfer interactions are important in the hydrolysis of cellulose and degra- dation of glucose. This work shows that Bronsted-Lewis acidic ILs are potential catalysts for the hydrolysis of cellulose to produce sugar.

关键词： cellulose hydrolysis ionic liquid density functional theory