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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

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

Power Inverted Topp–Leone Distribution in Acceptance sampling Plans

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Computers, Materials & Continua 2021年第4期67卷 991-1011页

作者： Tahani A.Abushal amal s.hassan Ahmed R.El-saeed said G.Nassr Faculty of science Umm AL-Qura UniversityMakkah Al Mukarramah715Saudi Arabia Faculty of Graduate studies for statistical Research Cairo UniversityGiza12613Egypt Obour High Institute for Management&Information Al-Sharqua44516Egypt Faculty of Business Administration Sinai UniversityAl-Arish45511Egypt

We introduce a new two-parameter model related to the inverted Topp–Leone distribution called the power inverted Topp–Leone(PITL)*** properties of the PITL distribution are stated;including;quantile measures,moments,moment generating function,probability weighted moments,Bonferroni and Lorenz curve,stochastic ordering,incomplete moments,residual life function,and entropy *** sampling plans are developed for the PITL distribution,when the life test is truncated at a pre-specified *** truncation time is assumed to be the median lifetime of the PITL distribution with pre-specified *** minimum sample size necessary to ensure the specified life test is obtained under a given consumer’s *** results for given consumer’s risk,parameters of the PITL distribution and the truncation time are *** estimation of the model parameters is argued using maximum likelihood,least squares,weighted least squares,maximum product of spacing and Bayesian methods.A simulation study is confirmed to evaluate and compare the behavior of different *** real data applications are afforded in order to examine the flexibility of the proposed model compared with some others *** results show that the power inverted Topp–Leone distribution is the best according to the model selection criteria than other competitive models.

关键词： Inverted Topp-Leone distribution acceptance sampling plans maximum likelihood estimators weighted least squares estimators Bayesian estimators

RPL-Based IoT Networks under Decreased Rank Attack:Performance Analysis in static and Mobile Environments

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Computers, Materials & Continua 2024年第1期78卷 227-247页

作者： amal Hkiri Mouna Karmani Omar Ben Bahri Ahmed Mohammed Murayr Fawaz hassan Alasmari Mohsen Machhout Physic Department Electronics and Micro-Electronics LaboratoryFaculty of Sciences of MonastirMonastir5000Tunisia Department of science and Technology College of RanyahTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)*** its significance,RPL’s susceptibility to attacks remains a *** paper presents a comprehensive simulation-based analysis of the RPL protocol’s vulnerability to the decreased rank attack in both static andmobilenetwork *** employ the Random Direction Mobility Model(RDM)for mobile scenarios within the Cooja *** systematic evaluation focuses on critical performance metrics,including Packet Delivery Ratio(PDR),Average End to End Delay(AE2ED),throughput,Expected Transmission Count(ETX),and Average Power Consumption(APC).Our findings illuminate the disruptive impact of this attack on the routing hierarchy,resulting in decreased PDR and throughput,increased AE2ED,ETX,and *** results underscore the urgent need for robust security measures to protect RPL-based IoT ***,our study emphasizes the exacerbated impact of the attack in mobile scenarios,highlighting the evolving security requirements of IoT networks.

关键词： RPL decreased rank attacks mobility random direction model

Perceived stress among staff in saudi Arabian dental colleges before and after an accreditation process: A cross-sectional study

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World Journal of Clinical Cases 2024年第4期12卷 758-765页

作者： amal s shaiban Department of Restorative Dental science College of DentistryKing Khalid UniversityAbha 61471Saudi Arabia

BACKGROUND Accreditation processes are extensively employed to guarantee the quality of higher education ***,this process can potentially generate a stressful atmosphere for staff,thus impacting their ability to perform optimally under *** To examine the knowledge of the National Commission for Academic Assessment and Accreditation(NCAAA)and its effects on perceived stress among dental college staff before and after the program accreditation *** The present cross-sectional questionnaire-based study included 300 employees from three dental *** same employees had to fill out the questionnaire 1 mo after the NCAAA *** Approximately 51.33%of the included employees believed that NCAAA is essential to attract quality students to join the program before and after the program.A total of 44.67%felt that their stress was high before,and 31.33%had low stress levels before and after *** findings were statistically significant(P≤0.05).CONCLUsION NCAAA raised the prestige of the institution and specific programmes and increased prospects to attract better students,staff,and money,according to the *** addition to their needed teaching,research,and other service responsibilities,this work requires a tremendous amount of faculty effort and may cause them stress.

关键词： National Commission for Academic Assessment and Accreditation Accreditation process Perceived stress staff

Development of sustainable thermal insulation based on bio-polyester filled with date pits

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Journal of Bioresources and Bioproducts 2024年第1期9卷 74-89页

作者： amal Mlhem Thomas Teklebrhan Evenezer Bokuretsion Basim Abu-Jdayil Chemical&Petroleum Engineering Department United Arab Emirates UniversityPO Box 15551United Arab Emirates National Water and Energy Center United Arab Emirates UniversityPO Box 15551United Arab Emirates

Date palm pit(DPP)-filled poly(-hydroxybutyrate)(PHB)composites were prepared,evaluated,and characterized to determine their thermal insulation *** conductivity values ranged between 0.086 and 0.100 W/(m·K).At a maximum filler concentration(50%(w)),the specific heat capacity and thermal diffusivity were 1183 J/(kg·K)and 0.0689 mm^(2)/s,*** DPP increased the thermal stability,and the highest compressive strength obtained was 80 MPa at 30%filler *** PHB-DPP composites exhibited promising water absorption(less than 6%)and tensile strength(6-14 MPa).Date-pit-based PHB composites could be used in sustainable building engineering and cleaner production.

关键词： Green construction material sustainable thermal insulator Date pit Polyhydroxybutyrate