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Generalized Marshall Olkin Inverse Lindley Distribution with Applications

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Computers, Materials & Continua 2020年第9期64卷 1505-1526页

作者： Rashad Bantan Amal s.hassan Mahmoud Elsehetry Deanship of scientific Research King AbdulAziz UniversityJeddah21589Saudi Arabia Faculty of Graduate studies for statistical Research Cairo UniversityCairo11865Egypt Deanship of Information Technology King AbdulAziz UniversityJeddah21589Saudi Arabia

In this article,a new generalization of the inverse Lindley distribution is introduced based on Marshall-Olkin family of *** call the new distribution,the generalized Marshall-Olkin inverse Lindley distribution which offers more flexibility for modeling lifetime *** new distribution includes the inverse Lindley and the Marshall-Olkin inverse Lindley as special *** properties of the generalized Marshall-Olkin inverse Lindley distribution are discussed and investigated including,quantile function,ordinary moments,incomplete moments,moments of residual and stochastic *** likelihood method of estimation is considered under complete,Type-I censoring and Type-II *** likelihood estimators as well as approximate confidence intervals of the population parameters are discussed.A comprehensive simulation study is done to assess the performance of estimates based on their biases and mean square *** notability of the generalized Marshall-Olkin inverse Lindley model is clarified by means of two real data *** results showed the fact that the generalized Marshall-Olkin inverse Lindley model can produce better fits than power Lindley,extended Lindley,alpha power transmuted Lindley,alpha power extended exponential and Lindley distributions.

关键词： Generalized Marshal-Olkin family inverse Lindley distribution maximum likelihood estimation

Zubair Lomax Distribution:Properties and Estimation Based on Ranked set sampling

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Computers, Materials & Continua 2020年第12期65卷 2169-2187页

In this article,we offer a new adapted model with three parameters,called Zubair Lomax *** new model can be very useful in analyzing and modeling real data and provides better fits than some others new *** properties of the Zubair Lomax model are determined by moments,probability weighted moments,Renyi entropy,quantile function and stochastic ordering,among *** likelihood method is used to estimate the population parameters,owing to simple random sample and ranked set sampling *** behavior of the maximum likelihood estimates for the model parameters is studied using Monte Carlo *** measures including biases,mean square errors and relative efficiencies are used to compare *** the simulation study,we observe that the estimates based on ranked set sampling are more efficient compared to the estimates based on simple random *** importance and flexibility of Zubair Lomax are validated empirically in modeling two types of lifetime data.

关键词： Lomax distribution Zubair-g family moments maximum likelihood estimation ranked set sampling

Kumaraswamy Inverted Topp–Leone Distribution with Applications to COVID-19 Data

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Computers, Materials & Continua 2021年第7期68卷 337-358页

作者： Amal s.hassan Ehab M.Almetwally Gamal M.Ibrahim Faculty of Graduate studies for statistical Research Cairo UniversityGiza12613Egypt Faculty of Business Administration Delta University of Science and TechnologyMansoura35511Egypt High Institute for Management sciences Belqas35511Egypt

In this paper, an attempt is made to discover the distributionof COVID-19 spread in different countries such as;saudi Arabia, Italy,Argentina and Angola by specifying an optimal statistical distribution for analyzing the mortality rate of COVID-19. A new generalization of the recentlyinverted Topp Leone distribution, called Kumaraswamy inverted Topp–Leonedistribution, is proposed by combining the Kumaraswamy-G family and theinverted Topp–Leone distribution. We initially provide a linear representationof its density function. We give some of its structure properties, such as quantile function, median, moments, incomplete moments, Lorenz and Bonferronicurves, entropies measures and stress-strength reliability. Then, Bayesian andmaximum likelihood estimators for parameters of the Kumaraswamy invertedTopp–Leone distribution under Type-II censored sample are *** estimator is regarded using symmetric and asymmetric loss functions. As analytical solution is too hard, behaviours of estimates have beendone viz Monte Carlo simulation study and some reasonable comparisonshave been presented. The outcomes of the simulation study confirmed theefficiencies of obtained estimates as well as yielded the superiority of Bayesianestimate under adequate priors compared to the maximum likelihood *** to COVID-19 in some countries showed that the new distributionis more appropriate than some other competitive models.

关键词： Kumaraswamy-G family maximum likelihood Bayesian method COVID-19 moments quantile function stress-strength reliability

sOLUTION OF THE RAYLEIGH PROBLEM FOR A POWER-LAW NON-NEWTONIAN CONDUCTING FLUID VIA GROUP METHOD

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Applied Mathematics and Mechanics(English Edition) 2002年第6期23卷 639-646页

作者： Mina B.Abd-el-Malek Nagwa A.Badran Hossam s.hassan Department of Engineering Mathematics and Physics Faculty of Engineering Alexandria University Alexandria Egypt Department of Basic and Applied science Arab Academy for Science and Technology and Maritime Transport Alexandria Egypt

An investigation is made of the magnetic Rayleigh problem where a semi_infinite plate is given an impulsive motion and thereafter moves with constant velocity in a non_Newtonian power law fluid of infinite extent. The solution of this highly non_linear problem is obtained by means of the transformation group theoretic approach. The one_parameter group transformation reduces the number of independent variables by one and the governing partial differential equation with the boundary conditions reduce to an ordinary differential equation with the appropriate boundary conditions. Effect of the some parameters on the velocity u(y,t) has been studied and the results are plotted.

关键词： Rayleigh problem group method non_linearity conducting fluid non_Newtonian power law fluid

Metastability of Ising spin chains with nearest—neighbour and next—nearest—neighbour interactions in random fields

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Chinese Physics B 2002年第9期11卷 948-954页

作者： G.Ismail s.hassan DepartmentofMathematics FacultyofScienceZagazigUniversityZagazigEgypt

One-dimensional Ising systems in random fields (RFs) are studied taking into account the nearest-neighbour andnext-nearest-neighbour interactions. We investigate two distributions of RFs: binary and Gaussian distributions. Weconsider four cases of the exchange couplings: ferro-ferromagnetic (F-F), ferro-antiferromagnetic (F-AF), antiferro-ferromagnetic (AF-F) and antiferro-antiferromagnetic (AF-AF). The energy minima of chains of no more than 30 spinswith periodic boundary conditions are analysed exactly. We found that the average number of energy minima growsexponentially with the number of spins in both cases of *** energy distributions across the corresponding energyminima are shown. The effects of RFs on both the average and density of metastable states are explained. For a weakRF, the energy distributions display a multipartitioned structure. We also discuss the frustration effect due to RFsand exchange fields. Finally, the distributions of magnetization are calculated. The absolute value of magnetizationaveraged over all metastable states decreases logarithmically with the number of spins.

关键词： random field metastable states nearest-neighbour next-nearest-neighbour magnetization

synthesis and antitumor activity of some new pyrazolo[1,5-α]pyrimidines

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Chinese Chemical Letters 2017年第2期28卷 388-393页

作者： Ashraf s.hassan Mohamed F.Mady Hanem M.Awad Taghrid s.Hafez Department of Organometallic and Organometalloid Chemistry National Research Centre Dokki 12622 CairoEgypt Department of Green Chemistry National Research Centre Dokki 12622 Cairo Egypt Department of Mathematics and Natural science Faculty of Science and Technology University of Stavanger N-4036 Stavanger Norway Department of Tanning Materials and Leather Technology National Research Centre Dokki 12622 Cairo Egypt

New series of pyrazolo[1,5-α]pyrimidine derivatives 7a-i,11a-c and schiff bases 13a-c were synthesized and screened for their in vitro antitumor activity against three human carcinoma cell lines,namely colorectal carcinoma（HCT116）,prostate adenocarcinoma（PC-3） and liver carcinoma（HepG-2） using MTT cytotoxicity assay at 100 μg/*** of the tested compounds displayed good anticancer activities against HCT-116 and PC-3 ***,compounds 7d and 11 a showed better antitumor activity than the rest of the compounds against both cell lines.A structure-activity relationship（sAR） has been discussed and structures of the newly synthesized compounds were confirmed by different spectral data（Ms,IR,^1H NMR and ^13C NMR） and elemental analysis.

关键词： 5-Amino-1H-pyrazole Pyrazolo[1 5-α]pyrimidine schiff bases MIT assay Anticancer activity structure activity relationship

Estimation of the stress-strength Reliability for Exponentiated Pareto Distribution Using Median and Ranked set sampling Methods

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Computers, Materials & Continua 2020年第8期64卷 835-857页

作者： Amer Ibrahim Al-Omari Ibrahim M.Almanjahie Amal s.hassan Heba F.Nagy Department of Mathematics Faculty of ScienceAl al-Bayt UniversityMafraq25113Jordan Department of Mathematics College of ScienceKing Khalid UniversityAbha62529Saudi Arabia statistical Research and studies support Unit King Khalid UniversityAbha62529Saudi Arabia Faculty of Graduate studies for statistical Research Cairo UniversityGiza12613Egypt

In reliability analysis,the stress-strength model is often used to describe the life of a component which has a random strength(X)and is subjected to a random stress(Y).In this paper,we considered the problem of estimating the reliability𝑅𝑅=P[Ystributions of both stress and strength are independent and follow exponentiated Pareto *** maximum likelihood estimator of the stress strength reliability is calculated under simple random sample,ranked set sampling and median ranked set sampling *** different reliability estimators under median ranked set sampling are *** estimators are obtained when both strength and stress have an odd or an even set *** two other estimators are obtained when the strength has an odd size and the stress has an even set size and vice *** performances of the suggested estimators are compared with their competitors under simple random sample via a simulation *** simulation study revealed that the stress strength reliability estimates based on ranked set sampling and median ranked set sampling are more efficient than their competitors via simple random *** general,the stress strength reliability estimates based on median ranked set sampling are smaller than the corresponding estimates under ranked set sampling and simple random sample ***:stress-strength model,ranked set sampling,median ranked set sampling,maximum likelihood estimation,mean square *** estimates under ranked set sampling and simple random sample methods.

关键词： stress-strength model ranked set sampling median ranked set sampling maximum likelihood estimation mean square error

Bayesian Analysis in Partially Accelerated Life Tests for Weighted Lomax Distribution

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Computers, Materials & Continua 2021年第9期68卷 2859-2875页

作者： Rashad Bantan Amal s.hassan Ehab Almetwally M.Elgarhy Farrukh Jamal Christophe Chesneau Mahmoud Elsehetry Deanship of scientific Research King Abdulaziz UniversityJeddah21589Kingdom of Saudi Arabia Faculty of Graduate studies for statistical Research Cairo UniversityGiza12613Egypt Faculty of Business Administration Delta University of Science and TechnologyMansoura11152Egypt The Higher Institute of Commercial sciences Al Mahalla Al Kubra31951AlgarbiaEgypt Department of statistics The Islamia University of BahawalpurPunjab 63100Pakistan Department of Mathematics LMNOUniversity of CaenCaen14032France Deanship of Information Technology King Abdulaziz UniversityJeddah21589Kingdom of Saudi Arabia

Accelerated life testing has been widely used in product life testing experiments because it can quickly provide information on the lifetime distributions by testing products or materials at higher than basic conditional levels of stress,such as pressure,temperature,vibration,voltage,or load to induce early *** this paper,a step stress partially accelerated life test(ssPALT)is regarded under the progressive type-II censored data with random *** removals from the test are considered to have the binomial *** life times of the testing items are assumed to follow lengthbiased weighted Lomax *** maximum likelihood method is used for estimating the model parameters of length-biased weighted *** asymptotic confidence interval estimates of the model parameters are evaluated using the Fisher information *** Bayesian estimators cannot be obtained in the explicit form,so the Markov chain Monte Carlo method is employed to address this problem,which ensures both obtaining the Bayesian estimates as well as constructing the credible interval of the involved *** precision of the Bayesian estimates and the maximum likelihood estimates are compared by *** addition,to compare the performance of the considered confidence intervals for different parameter values and sample *** Bootstrap confidence intervals give more accurate results than the approximate confidence intervals since the lengths of the former are less than the lengths of latter,for different sample sizes,observed failures,and censoring schemes,in most ***,the percentile Bootstrap confidence intervals give more accurate results than Bootstrap-t since the lengths of the former are less than the lengths of latter for different sample sizes,observed failures,and censoring schemes,in most *** performance comparison is conducted by the experiments with real data.

关键词： Partially accelerated life testing progressive type-II censoring length-biased weighted Lomax Bayesian and bootstrap confidence intervals

Entropy Bayesian Analysis for the Generalized Inverse Exponential Distribution Based on URRss

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Computers, Materials & Continua 2021年第12期69卷 3795-3811页

作者： Amer I.Al-Omari Amal s.hassan Heba F.Nagy Ayed R.A.Al-Anzi Loai Alzoubi Faculty of science Department of MathematicsAl al-Bayt UniversityMafraq25113Jordan Faculty of Graduate studies for statistical Research Cairo UniversityGiza12613Egypt Department of Mathematics College of Science and Human Studies at Hotat SudairMajmaah UniversityMajmaah11952Saudia Arabia

This paper deals with the Bayesian estimation of shannon entropy for the generalized inverse exponential *** that the observed samples are taken from the upper record ranked set sampling(URRss)and upper record values(URV)*** of Bayesian estimators are derived depending on a gamma prior distribution considering the squared error,linear exponential and precautionary loss functions,in addition,we obtain Bayesian credible *** random-walk Metropolis-Hastings algorithm is handled to generate Markov chain Monte Carlo samples from the posterior ***,the behavior of the estimates is examined at various record *** output of the study shows that the entropy Bayesian estimates under URRss are more convenient than the other estimates under URV in the majority of the ***,the entropy Bayesian estimates perform well as the number of records *** obtained results validate the usefulness and efficiency of the URV *** data is analyzed for more clarifying purposes which validate the theoretical results.

关键词： shannon entropy generalized inverse exponential distribution Bayesian estimators loss function ranked set sampling markov chain