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Modeling Liver Cancer and Leukemia Data Using Arcsine-Gaussian Distribution

Computers, Materials & Continua 2021年第5期67卷 2185-2202页

作者： Farouq Mohammad A.Alam Sharifah Alrajhi Mazen Nassar ahmed z.afify Department of Statistics Faculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of Statistics Faculty of CommerceZagazig UniversityZagazig44511Egypt Department of Statistics Mathematics and InsuranceBenha UniversityBenha13511Egypt

The main objective of this paper is to discuss a general family of distributions generated from the symmetrical arcsine *** considered family includes various asymmetrical and symmetrical probability distributions as special cases.A particular case of a symmetrical probability distribution from this family is the Arcsine–Gaussian *** statistical properties of this distribution including quantile,mean residual life,order statistics and moments are *** Arcsine–Gaussian parameters are estimated using two classical estimation methods called moments and maximum likelihood methods.A simulation study which provides asymptotic distribution of all considered point estimators,90%and 95%asymptotic confidence intervals are performed to examine the estimation efficiency of the considered methods *** simulation results show that both biases and variances of the estimators tend to zero as the sample size increases,i.e.,the estimators are asymptotically ***,when the sample size increases the coverage probabilities of the confidence intervals increase to the nominal levels,while the corresponding length decrease and approach *** real data sets from the medicine filed are used to illustrate the flexibility of the Arcsine–Gaussian distribution as compared with the normal,logistic,and Cauchy *** proposed distribution is very versatile to fit real applications and can be used as a good alternative to the traditional gaussian distribution.

关键词： Liver cancer data leukemia data normal distribution moments estimation maximum likelihood estimation

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Modeling COVID-19 Pandemic Dynamics in Two Asian Countries

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Computers, Materials & Continua 2021年第4期67卷 965-977页

作者： Jin zhao zubair Ahmad zahra Almaspoor M.El-Morshedy ahmed z.afify School of Finance Shanghai Lixin University of Accounting and FinanceShanghaiChina Department of Statistics Yazd UniversityYazdIran Department of Mathematics College of Science and Humanities in Al-KharjPrince Sattam bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Statistics Mathematics and InsuranceBenha UniversityBenha13511Egypt

The current epidemic outbreak COVID-19 first took place in the Wuhan city of China and then spread *** deadly disease affected millions of people and compelled the governments and other concerned institutions to take serious *** 0.28 million people have died from the COVID-19 outbreak as of May 11,2020,05:41 GMT,and the number is still increasing *** results of any scientific investigation of this phenomenon are still to ***,now it is urgently needed to evaluate and compare the disease dynamics to improve the quarantine activities and the level of individual protection,to at least speed up the rate of isolation of infected *** the domain of big data science and other related areas,it is always of interest to provide the best description of the data under ***,in this article,we compare the COVID-19 pandemic dynamics between two neighboring Asian countries,Iran and Pakistan,to provide a framework to arrange the appropriate quarantine *** tools for comparing this deadly pandemic dynamic have been presented that can be adopted to produce the bases for *** importantly,a new statistical model is developed to provide the best description of COVID-19 daily deaths data in Iran and Pakistan.

关键词： COVID-19 pandemic dynamics Pakistan mathematical modeling statistical methods Monte Carlo simulation

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The Lambert-G Family:Properties,Inference,and Applications

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 513-536页

作者： Jamal N.Al Abbasi ahmed z.afify Badr Alnssyan Mustafa S.Shama Accounting Department Ashur UniversityBaghdad10011Iraq Department of Statistics Mathematics and InsuranceBenha UniversityBenha13511Egypt Department of Management Information Systems and Production Management College of Business and EconomicsQassim UniversityBuraydah51452Saudi Arabia Department of Basic Sciences Common First Year(CFY)King Saud UniversityRiyadh11362Saudi Arabia Department of Mathematics and Statistics Osim Higher Institute of Administrative ScienceOsim12961Egypt

This study proposes a new flexible family of distributions called the Lambert-G *** Lambert family is very flexible and exhibits desirable *** three-parameter special sub-models provide all significantmonotonic and non-monotonic failure rates.A special sub-model of the Lambert family called the Lambert-Lomax(LL)distribution is *** expressions for the LL statistical properties are *** of the LL distribution are addressed mathematically based on its hazard *** estimation of the LL parameters is discussed using six estimation *** performance of this estimation method is explored through simulation *** usefulness and flexibility of the LL distribution are demonstrated empirically using two real-life data *** LL model better fits the exponentiated Lomax,inverse power Lomax,Lomax-Rayleigh,power Lomax,and Lomax distributions.

关键词： Lambert function Lomax distribution maximum likelihood hazard function statistical model simulation

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Effect of a chemical reaction on magnetohydrodynamic boundary layer flow of a Maxwell fluid over a stretching sheet with nanoparticles

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Particuology 2016年第6期14卷 154-161页

作者： ahmed A. afify Nasser S. Elgazery Department of Mathematics Faculty of Science Helwan University Ain Helwan PO Box 11795 Cairo Egypt Department of Mathematics Faculty of Education Ain Shams University Roxy Heliopolis Cairo Egypt

The influences of the convective boundary condition and heat generation/absorption on magnetohydro- dynamic boundary layer flow of a Maxwell fluid over a stretching surface in the presence of nanoparticles have been numerically investigated. In the model, the physical mechanisms responsible for Brownian motion and thermophoresis with a chemical reaction are considered. Similarity equations are derived and then solved using the shooting method with the fourth-order Runge-Kutta integration scheme, The rates of heat and mass transfer are enhanced with a destructive chemical reaction and Blot number. The opposite influence is found with a generative chemical reaction in the presence of Brownian motion and the thermophoretic property.

关键词： Magnetohydrodynamics Nanoparticle Maxwell fluid Boundary layer flow Chemical reaction

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Synthesis of znO Nanoparticles onto Sepiolite Needles and Determination of Their Sensitivity toward Humidity, NO_2 and H_2

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Journal of Materials Science & Technology 2016年第6期32卷 573-582页

作者： M.Hassan ahmed S.afify J.M.Tulliani Department of Applied Science and Technology Politecnico di Torino

This work investigated the sensitivity toward humidity, NO2 and H2 of znO modified sepiolite （Si12Mg8O30（OH）4.（H2O）4.8H2O）. To this aim, sepiolite powder was first modified by leaching magnesium ions in HCI then by precipitating nano-sized zn-based compounds under basic conditions. A subse- quent thermal treatment at 550 ℃ for 1 h was performed. The powders were characterized by X-ray diffraction （XRD）, specific surface area measurements, thermogravimetric and differential thermal anal- ysis and field emission scanning electron microscopy, as well as high resolution transmission electron microscopy. The XRD patterns showed that all leached heat treated samples were made of anhydrous sepiolite and of znO. Sensors were then obtained by screen printing these materials onto commercial alumina substrates with Pt electrodes. All the investigated compositions were capable of detecting NO2 down to ppm level and 20 ppm H2, at an optimal working temperature of 300°C. These detection limits are in line with the current best results reported in literature.

关键词： Clay minerals Gas sensor Sensitivity Hydrogen sensor Nitrogen Oxide

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Peristaltic Flow of Dusty Nanofluids in Curved Channels

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Computers, Materials & Continua 2021年第1期66卷 1011-1026页

作者： z.z.Rashed Sameh E.ahmed mathematics department jouf universityqurayyatsaudi arabia department of mathematics king khalid universityabhasaudi arabia

In this paper,numerical investigations for peristaltic motion of dusty nanofluids in a curved channel are *** systems of partial differential equations are presented for the nanofluid and dusty phases and then the approximations of the long wave length and low Reynolds number are *** physical domain is transformed to a rectangular computational model using suitable grid *** resulting systems are solved numerically using shooting method and mathematical forms for the pressure distributions are *** controlling parameters in this study are the thermal buoyancy parameter G_(r),the concentration buoyancy parameter Gc,the amplitude ratio,the Eckert number Ec,the thermophoresis parameter N_(t) and the Brownian motion parameter Nb and the dusty parameters D_(s);α_(s).The obtained results revealed that an increase in the Eckert number enhances the temperature of the fluid and dusty particles while the nanoparticle volume fraction is ***,both of the temperature and nanoparticles volume fraction are supported by the growing of the Brownian motion parameter.

关键词： Peristaltic motion dusty particles nanofluid curved channels

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A stable flat universe with variable cosmological constant in f(R,T)gravity

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Research in Astronomy and Astrophysics 2018年第10期18卷 65-74页

作者： Nasr ahmed Sultan z.Alamri Astronomy Department National Research Institute of Astronomy and GeophysicsHelwanCairoEgypt Mathematics Department Faculty of ScienceTaibah UniversitySaudi Arabia

In this paper, a general FRW cosmological model has been constructed in f（R, T） gravity reconstruction with variable cosmological constant. A number of solutions to the field equations has been generated by utilizing a form for the Hubble parameter that leads to Berman＇s law of constant deceleration parameter q =m - 1. The possible decelerating and accelerating solutions have been investigated. For （q 〉 0） we get a stable fiat decelerating radiation-dominated universe at q = 1. For （q 〈 0） we get a stable accelerating solution describing a flat universe with positive energy density and negative cosmological constant. Nonconventional mechanisms that are expected to address the late-time acceleration with negative cosmological constant have been discussed.

关键词： modified gravity cosmology deceleration parameter

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Phenotypic methods of greater accuracy to detect the mecA gene product for the recognition of MRSA in resource constraint settings

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Asian Pacific Journal of Tropical Medicine 2010年第9期3卷 741-744页

作者： Rasheed MU ahmed z Assistant Professor Department of Medical Microbiology Haramaya University HararEthiopia Head-School of Medical Laboratory Technology Jimma University JimmaEthiopia

Objective:To evaluate the detection of methicillin resistant Staphylococcus aureus(MRSA) and analyze the performance of Mastalex MRSA(Mast,UK).Methods:Two hundred and ten Staphylococcus aureus(***) strains were isolated from different clinical samples and were tested for methicillin resistance by Oxacillin(1μg) and Cefoxitin(30μg) disc diffusion, oxacillin agar screen,and minimum inhibitory concentration of oxacillin and *** isolates were grown on the blood agar and mannitol salt agar with(2 mg/L) and without oxacillin for the analysis of Mastalex ***:Out of 210 *** strains tested,103 strains were detected as methicillin resistant by Cefoxitin disk diffusion,Cefoxitin minimal inhibitory concentration(MlC) and Mastalex MRSA *** oxacillin disc diffusion and oxacillin agar screen detected 91 and 97 MRSA *** Cefoxitin MIC test performance was equivalent to Cefoxitin disc diffusion.103(100%) strains grown on blood agar without and with oxacillin,and 76(74%) and 93(91%) strains grown on mannitol salt agar without and with oxacillin shown positive agglutination with Mastalex MRSA test ***:The cefoxitin disk diffusion/ Mastalex MRSA is very suitable for detection of MRSA and the tests can be an alternative to PCR for detection of MRSA in resource constraint *** test would be particularly useful when confirmation of resistance is urgently required.

关键词： Staphylococcus aureus Oxacillin Cefoxitin Mastalex MRSA

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Production of porous silica by the combustion of rice husk ash for tundish lining

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Journal of University of Science and Technology Beijing 2008年第3期15卷 307-313页

作者： Y.M.z.ahmed E.M.Ewais z.I.zaki Central Metallurgical Research and Development Institute(CMRDI)

In order to study the production of porous silica compacts by the combustion of rice husk ash （RHA） for tundish lining, the experimental design technique was used to evaluate the effect of firing temperature, soaking time and compaction pressure on controlling both the porosity degree and compressive strength of rice husk ash compacts. The results revealed that while the porosity degree of the compacts decreased with the increase in the entire studied parameters, the compressive strength exhibited another trend especially at a lower soaking time. At a lower soaking time, the increase in firing temperature led to a slight decrease in compressive strength and then increasing thereafter. The porous silica compacts having 30% porosity and 〉 2.5 MPa compressive strength suitable for tundish lining could be obtained from the combustion of rice husk ash compacts.

关键词： porous silica rice husk ash tundish lining compressive strength porosity

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Identification of three major Bemisia tabaci biotypes in China based on morphological and DNA polymorphisms

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Progress in Natural Science:Materials International 2009年第6期19卷 713-718页

作者： Muhammad z.ahmed Vartika Mathur Department of Entomology South China Agricultural University Department of zoology Sri Venkateswara CollegeUniversity of Delhi

The sweet potato whitefly, Bemisia tabaci, is a complex species, and many of its biotypes are important agricultural pests. The B and Q biotypes are invasive and coexist with the native Cv biotype on vegetable and ornamental crops in China. In this study, these three bio- types were identified based on their morphological characteristics, RAPD-PCR analysis, and DNA sequences of the COI gene. The ante-rior and posterior wax fringes of the B, Q, and Cv biotypes significantly differed from each other. Based on this morphological characteristic, the three biotypes can easily be distinguished in greenhouses and fields. Genomic DNA RAPD-PCR band patterns also revealed differences between these biotypes using the H16 primer. The B biotype has three bright DNA bands between 250 and 600 bp, the Q biotype only has one bright band at 300 bp, while the Cv biotype has no band between 250 and 500 bp. Both the Cv and Q biotypes have two bright bands at 750 and 1000 bp while the B biotype has only one band at 1000 bp. Based on the COI gene, the genetic identity between B and Cv, B and Q, and Q and CV was 85.8%, 94.7%, and 86.0%, respectively. The MP tree indicated that the phylogenetic relationship between the B and Q biotypes is much closer than that between the B and Cv or the Q and Cv biotypes. The uses of the morphological, RAPD-PCR, and DNA sequencing methods in biotype identification of B. tabaci are discussed.

关键词： Bemisia tabaci complex Biotype DNA polymorphism Identification Morphology

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