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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

Effect of Y^(3+), Gd^(3+) and La^(3+) dopant ions on structural, optical and electrical properties of o-mullite nanoparticles

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Journal of Rare Earths 2014年第1期32卷 37-42页

作者： M.M.S.Sanad M.M.rashad E.A.Abdel-Aal M.F.El-Shahat K.Powers Central Metallurgical R & D Institute Particle Engineering Research Center University of Florida Faculty of Science Ain Shams University

Dielectric ceramics of M（x）Al6（1-x）Si2O13 doped mullite were synthesized via co-precipitation technique. The X-ray diffrac-tion profiles revealed that these nanoparticles were crystallized well and the volume of mullite unit cell was increased as a function of the ionic radius of dopant ion. TEM images showed regular orthorhombic crystal morphology for the pure mullite sample. Meanwhile, the doped samples exhibited slightly distorted crystal morphology of larger particle sizes. DSC thermograms evinced that the exo-thermic peak temperature of mullite was shifted to the lower value with M3＋ion insertion. The photoluminescence spectra were stud-ied for mullite samples, and it was found that the intensity of the emission spectra was affected by the M3＋ion type. It was found that, Y3＋doped mullite achieved the minimum dielectric loss value of 0.01 in the radio wave frequency region （1 MHz）. Meanwhile, Gd3＋doped mullite achieved the minimum dielectric loss value of 0.09 in the microwave frequency region （1 GHz）.

关键词： rare earths doped mullite photoluminescence crystallization temperature dielectric ceramics

Modeling the impacts of temperature and precipitation changes on soil CO_2 fluxes from a Switchgrass stand recently converted from cropland

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Journal of Environmental Sciences 2016年第5期28卷 15-25页

作者： Liming Lai Sandeep Kumar Rajesh Chintala Vance N. Owens David Clay Joseph Schumacher Abdul-Sattar Nizami Sang Soo Lee rashad Rafique Department of Plant Science South Dakota State University Brookings South Dakota 57007 USA. North Central Sun Grant Center South Dakota State University Brookings South Dakota 57007 USA Center of Excellence in Environmental Studies (CEES) King Abdulaziz University Abdullah Sulayman Jeddah 22254 Saudi Arabia kangwon National University Chuncheon 200-701 South Korea Joint global Change Research Institute Pacific Northwest National Lab College Park Maryland 20740 USA

Switchgrass（Panicum virgatum L.） is a perennial C_4 grass native to North America and successfully adapted to diverse environmental conditions. It offers the potential to reduce soil surface carbon dioxide（CO_2） fluxes and mitigate climate change. However, information on how these CO_2 fluxes respond to changing climate is still lacking. In this study, CO_2 fluxes were monitored continuously from 2011 through 2014 using high frequency measurements from Switchgrass land seeded in 2008 on an experimental site that has been previously used for soybean（Glycine max L.） in South Dakota, USA. DAYCENT, a process-based model, was used to simulate CO_2 fluxes. An improved methodology CPTE[Combining Parameter estimation（PEST） with ＂Trial and Error＂ method] was used to calibrate DAYCENT. The calibrated DAYCENT model was used for simulating future CO_2 emissions based on different climate change scenarios. This study showed that：（i） the measured soil CO_2 fluxes from Switchgrass land were higher for 2012 which was a drought year, and these fluxes when simulated using DAYCENT for long-term（2015–2070） provided a pattern of polynomial curve;（ii） the simulated CO_2 fluxes provided different patterns with temperature and precipitation changes in a long-term,（iii） the future CO_2 fluxes from Switchgrass land under different changing climate scenarios were not significantly different, therefore, it can be concluded that Switchgrass grown for longer durations could reduce changes in CO_2 fluxes from soil as a result of temperature and precipitation changes to some extent.

关键词： Carbon dioxide Switchgrass DAYCENT Climate change

High temperature formability of graphene nanoplatelets-AZ31 composites fabricated by stir-casting method

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Journal of Magnesium and Alloys 2016年第4期4卷 270-277页

作者： Muhammad rashad Fusheng Pan Yanglu Liu Xianhua Chen Han Lin Rongjian Pan Muhammad Asif Jia She College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China Chongqing Academy of Science and Technology Chongqing 401123China School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China Nuclear Power Institute of China Chengdu 610213China

Outstanding mechanical properties of graphene nanoplatelets(GNPs)make them ideal reinforcement for mass production of *** this research,the composites were fabricated by stir-casting *** were added in 1.5 and 3.0 wt.%into Mg–3wt.%Al–1wt.%Zn(AZ31)magnesium *** cast ingots were preheated for one hour and extruded at 350℃ with extrusion ratio of 5.2:*** extruded AZ31-GNPs composites were micro-structurally characterized with X-ray diffraction,optical microscopy and scanning electron *** microhardness of synthesized materials was investigated both in parallel and perpendicular to extrusion *** temperature mechanical testing revealed that with increasing GNP’s content,tensile fracture strain was remarkably increased without significant compromise in tensile ***,as extruded AZ31-3GNPs composites were subjected to tensile testing at temperatures ranging from 75℃ to 300℃ with initial strain rate of 2×10^(−3)s^(−1) to evaluate high temperature formability of *** was found that like CNTs,GNPs also have the potential to sustain tensile strength at high temperatures.

关键词： Metal matrix composites Mechanical properties Stir-casting method Elevated temperatures

Strain-regulated sensing properties of α-Fe_(2)O_(3) nano-cylinders with atomic carbon layers for ethanol detection

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Journal of Materials Science & Technology 2021年第9期68卷 132-139页

作者： Huajing Xiong Jianan Fu Jinyao Li rashad Ali Hong Wang Yifan Liu Hua Su Yuanxun Li Woon-Ming Lau Nasir Mahmood Chunhong Mu Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Institute of Chemistry National Institute of Measurement and Testing Technology of ChinaChengdu 610021China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Jiangxi Guo Chuang Industrial Park Development Co. LtdGanzhou 341000China Institute of Fundamental and Frontier Science University of Electronic Science and Technology of ChinaChengdu 610054China School of Engineering RMIT University124 La Trobe Street3001 MelbourneVictoriaAustralia National Engineering Research Center of Electromagnetic Radiation Control Materials State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and Technology of ChinaChengdu 611731China

The sensitivity of ethanol sensor is of paramount importance in a variety of areas,including chemical production with ethanol,alcohol testing for driving safety,***,α-Fe_(2)O_(3) nano-cylinders with atomic carbon layers are synthesized,for the first time,through in-situ catalytic chemical vapor deposition combined with hydrothermal techniques for the detection of *** reported α-Fe_(2)O_(3)@C nano-cylinders with double surficial strain effects deliver an ethanol detection sensitivity of 8 times as compared with α-Fe_(2)O_(3) nano-cylinders,10 times higher as compared with its detection sensitivity to ammonia,para-xylene,methanol and *** sensor also exhibits over-14-day operation stability and the minimum detection limit of 10 *** our best knowledge,the performances surpass those of previously reported α-Fe_(2)O_(3).Such attractive performances are attributed to the enhanced charge transfer in α-Fe_(2)O_(3) owing to the double surficial strain effects of α-Fe_(2)O_(3)@C nano-cylinders and the efficient adsorption of ethanol with atomic carbon layers.

关键词： Gas sensor Nano-cylinder Hybrid microstructure Sensitivity Carbon coating

A glimpse at Great Wall from the coast of Caspian Sea

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Voice of Friendship 2021年第2期 31-33页

作者： rashad Seyfaddin Karimov Azerbaijan-China Cooperation Federation

In 1850,Karl Marx wrote:"Now Chinese socialism may admittedly be the same in relation to European socialism as Chinese philosophy is in relation to Hegelian ***,it is a gratifying fact that in eight years the calico bales of the English bourgeoisie have brought the oldest and least perturbable kingdom on Earth to the eve of a social upheaval,which,in any event.

关键词： admitted Earth brought

Molecular mechanisms of the anti-obesity potential effect of Moringa oleifera in the experimental model

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Asian Pacific Journal of Tropical Biomedicine 2017年第3期7卷 214-221页

作者： Fateheya Mohamed Metwally Hend Mohamed rashad Hanaa Hamdy Ahmed Asmaa Ahmed Mahmoud Ehab Ragaa Abdol Raouf Aboelfetoh Mohamed Abdalla Environmental and Occupational Medicine National Research CentreGizaEgypt Department of Hormones National Research CentreGizaEgypt Department of Zoology Faculty of ScienceAin Shams UniversityCairoEgypt Department of Research on Children with Special Needs National Research CentreGizaEgypt Department of Horticulture Crops Technology National Research CentreGizaEgypt

Objective: To elucidate the molecular mechanisms of the potent anti-obesity effect of Moringa oleifera Lam.(M. oleifera) ethanolic extract and to clarify the link between these mechanisms and the associated metabolic and vascular risks in the experimental model of visceral ***: M. oleifera ethanolic extract was orally administered at 600 mg/kg body weight in obese female rats daily for 12 weeks. At the end of treatment, body weight was determined, and the atherogenic index, coronary artery index, glucose level, insulin resistance status, liver and kidney functions were assessed. Also, the m RNA of leptin, adiponectin and resistin in visceral adipose tissue was determined by quantitative real ***: The results showed that M. oleifera extract down-regulated m RNA expression of leptin and resistin, while it up-regulated adiponectin gene expression in obese rats relative to untreated obese control counterparts. This amelioration of genes expression was paralleled by a reduction in body weight and improvement of the atherogenic index and coronary artery index, as well as glucose level and insulin resistance value without adverse effects on liver or kidney functions, versus the untreated obese control ***: It is reasonable to assume that the anti-obesity, anti-atherogenic and antidiabetic properties of M. oleifera are mechanistically achieved via working directly on the adipokines of the visceral adipose tissue. Therefore, M. oleifera may be a good therapeutic candidate for the symptoms of metabolic syndrome.

关键词： Moringa oleifera Lam Visceral adipose tissue Adipokines Gene expression Rats

Medical treatment of inflammatory punctual stenosis monitored by anterior segment optical coherence tomography

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International Journal of Ophthalmology(English edition) 2020年第7期13卷 1074-1078页

作者： Hanan Youssef Elalfy Mahmoud A Elsamkary Ahmed M Shafek Elridy Tarek M Saad Saad Mohamed rashad Samah M Fawzy Al Dorra Subspecialty Ophthalmology Centre Cairo 11751Egypt Department of Ophthalmology Ain Shams UniversityCairo 11471Egypt

AIM:To evaluate the role of medical treatment in the management of inflammatory punctum stenosis guided by spectral domain anterior segment optical coherence tomography(OCT).METHODS:This prospective study included 60 patients complaining of epiphora due to inflammatory punctual *** were divided into two groups:Group A(30 patients)treated with a combination of preservative free hydrocortisone sodium phosphate 3.35 mg/m L eye drops,and preservative free artificial tears based on sodium hyaluronate,polyethylene and propylene Glycol;Group B(30 patients)treated with the same preservative free artificial tears *** normal subjects were included for comparison of pre-treatment anatomical *** starting treatment,all patients underwent anterior segment assessment including slit lamp examination,measurement of intraocular pressure(IOP),fluorescein dye disappearance test,and measurement of the outer punctum diameter(OPD)by Spectral domain anterior segment *** assessments were repeated at each follow up done at 1 and 3 mo later,together with subjective evaluation of patient’s satisfaction of the treatment outcome by simple rating ***:Punctual diameter increased significantly with treatment in both groups(P<0.0001);although the widening was more in Group A as compared to group B(16.2%vs 8%of the original punctual size,mean difference of 28.933μm,P=0.0076).Subjective satisfaction with treatment outcome was also better in group A(70%vs 40%,Chi-square P=0.0397).CONCLUSION:A combination of preservative free steroid eye drops and artificial tears causes significant widening of inflammed stenotic punctae and improvement of the associated epiphora.

关键词： artificial tears hydrocortisone inflammatory punctual stenosis optical coherence tomography preservatives

Dimensionality engineering of metal halide perovskites

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Frontiers of Optoelectronics 2020年第3期13卷 196-224页

作者： rashad FKAHWAGI Sean TTHORNTON Ben SMITH Ghada LKOLEILAT Department of Chemical Engincering Dalhousic UniversityHalifaxNova ScotiaB3J IZ1Canada

Metal halide perovskites are a class of materials that are ideal for photodetectors and solar cells due to their excellent optoelectronic *** low-cost and low temperature synthesis have made them attractive for extensive research aimed at revolutionizing the semiconductor *** rich chemistry of metal halide perovskites allows compositional engineering resulting in facile tuning of the desired optoelectronic ***,using different experimental synth-esis and deposition techniques such as solution processing,chemical vapor deposition and hot-injection methods,the dimensionality of the perovskites can be altered from 3D to 0D,each structure opening a new realm of applications due to their unique *** engineering includes both morphological engineering reducing the thickness of 3D perovskite into atomically thin films and molecular engineering--incorporating long-chain organic cations into the perovskite mixture and changing the composition at the molecular *** optoelectronic properties of the perovskite structure including its band gap,binding energy and carrier mobility depend on both its composition and *** plethora of different photodetectors and solar cells that have been made with different compositions and dimensions of perovskite will be reviewed *** will conclude our review by discussing the kinetics and dynamics of different dimen-sionalities,their inherent stability and toxicity issues,and how reaching similar performance to 3D in lower dimensionalities and their large-scale deployment can be achieved.

关键词： optoclectronics solar cells perovskite photo-detectors metal halides dimensionality