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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

Topp-Leone Odd Fréchet Generated Family of Distributions with Applications to COVID-19 Data sets

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Computer Modeling in Engineering & sciences 2020年第10期125卷 437-458页

作者： sanaa Al-Marzouki Farrukh jamal Christophe Chesneau Mohammed Elgarhy statistics Department Faculty of ScienceKing AbdulAziz UniversityJeddah21551Saudi Arabia Department of statistics Govt.S.A Postgraduate College Dera Nawab SahibBahawalpur63100Pakistan Universitéde Caen Normandie LMNOCampus IIScience 3Caen14032France Valley High Institute for Management Finance and Information systems Obour11828Egypt

Recent studies have pointed out the potential of the odd Fréchet family(or class)of continuous distributions in fitting data of all *** this article,we propose an extension of this family through the so-called“Topp-Leone strategy”,aiming to improve its overall flexibility by adding a shape *** main objective is to offer original distributions with modifiable properties,from which adaptive and pliant statistical models can be *** the new family,these aspects are illustrated by the means of comprehensive mathematical and numerical *** particular,we emphasize a special distribution with three parameters based on the exponential *** related model is shown to be skillful to the fitting of various lifetime data,more or less *** all the possible applications,we consider two data sets of current interest,linked to the COVID-19 *** concern daily cases confirmed and recovered in Pakistan from March 24 to April 28,*** a result of our analyzes,the proposed model has the best fitting results in comparison to serious challengers,including the former odd Fréchet model.

关键词： General family of distributions asymmetric distributions probabilistic properties parametric estimation confidence intervals COVID-19 pandemic data analysis

structural & Magnetic Characterizations of NiLiZn Nanoferrites synthesized by Co-precipitation Method

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Journal of Materials science & Technology 2011年第11期27卷 991-995页

作者： D.N. Rohadiana Z.A.Z. jamal s.B. jamaludin M.F. Bari J. Adnan sustainable Engineering Research Cluster Universiti Malaysia Perlis school of Microelectronic Engineering Universiti Malaysia Perlis

synthesis of ***（0.5-x）Fe204 nanoparticles with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 were realized via coprecipitation method. X-ray diffraction （XRD） and vibrating sample magnetometer （VsM） measurements were performed on the samples to determine the characteristics of the crystal structures and the magnetic properties of the samples, respectively. The spinel phase structures of the samples were confirmed by XRD analysis. Patterns of decreased lattice parameter and increased crystallite size values were observed by increasing the Li concentration at longer synthesis reaction periods. similarly, for the magnetic properties, both the saturation magnetization （Ms） and coercivity （Hc） were found to vary with increasing patterns at higher Li doping levels and longer synthesis reaction periods. The results and mechanisms concerned were discussed.

关键词： Lithium nickel zinc ferrite Co-precipitation Crystal structure Magnetic properties

Comparison of reflux esophagitis and its complications between African Americans and non-Hispanic whites

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World Journal of Gastroenterology 2009年第23期15卷 2878-2881页

作者： Kenneth J Vega sian Chisholm M Mazen jamal Divisions of Gastroenterology and General Internal Medicine University of Florida Health Sciences Center Jacksonville Florida 32207 United States Gastroenterology section Veterans Affairs Medical Center 5901 E. 7th St. Long Beach CA 90822 United States

AIM: To determine the effect of ethnicity on the severity of reflux esophagitis (RE) and its complications. METHODs: A retrospective search of the endoscopy database at the University of Florida Health science Center/Jacksonville for all cases of reflux esophagitis and its complications from January 1 to March 31, 2001 was performed. Inclusion criteria were endoscopic evidence of esophagitis using the LA classif ication, reflux related complications and self-reported ethnicity. The data obtained included esophagitis grade, presence of a hiatal hernia, esophageal ulcer, stricture and Barrett's esophagus, and endoscopy indication. REsULTs: The search identified 259 patients with RE or its complications, of which 171 were non-Hispanic whites and 88 were African Americans. The mean ages and male/female ratios were similar in the two groups. RE grade, esophageal ulcer, stricture and hiatal hernia frequency were likewise similar in the groups. Barrett's esophagus was present more often in non-Hispanic whites than in African Americans (15.8% vs 4.5%; P s a more frequent indication for endoscopy in non-Hispanic whites with erosive esophagitis than in African Americans (28.1% vs 7.9%; P sION: Distribution of RE grade and frequency of reflux-related esophageal ulcer, stricture andhiatal hernia are similar in non-Hispanic whites and African Americans. Heartburn was more frequently and nausea/vomiting less frequently reported as the primary endoscopic indication in non-Hispanic whites compared with African Americans with erosive esophagitis or its complications. African Americans have a decreased prevalence of Barrett's esophagus compared with non-Hispanic whites.

关键词： Reflux esophagitis African American Hiatal hernia Barrett's esophagus

Filtered High Gain Observer for an Electric Vehicle’s Electro-hydraulic Brake: Design and Optimization Using Multivariable Newton-based Extremum seeking

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Chinese Journal of Electrical Engineering 2023年第4期9卷 73-87页

作者： jamal El-bakkouri Hamid Ouadi Fouad Giri Mohamed Khafallah ENsEM Hassan II University of CasablancaCasablanca BP 8118Morocco ENsAM Rabat Mohammed V UniversityRabat BP 6207Morocco Department of Electrical Engineering University of Caen NormandyCaen 14032France

Designing high-gain observers(HGOs)for the state estimation of an electric vehicle’s electrohydraulic brake(EHB)system is *** type of observer is applicable to model nonlinearities and constant feature ***,they are very sensitive to measurement noise,which is unavoidable in *** first novelty of this study is that it compensates for the measurement noise using a filtered high-gain observer(FHGO)to ensure EHB state *** proposed FHGO provides an estimate of the master cylinder pressure,motor current,and rotor speed from measurements of the rotor *** second novelty is the design of an extremum-seeking(Es)optimization loop to adjust the FHGO gains *** performance of the developed FHGO with Es-based online gain optimization was highlighted in the presence of model uncertainties and output measurement noise using a Matlab/simulink *** superiority of the FHGO(even with a fixed gain)over a standard high gain observer(sHGO)was also demonstrated.

关键词： Electrohydraulic brake filtered HGO measurement noise optimization extremum-seeking Lyapunov theory

Thrust characteristics of nano-carbon/Al/oxygenated salt nanothermites for micro-energetic applications

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Defence Technology（防务技术） 2023年第12期30卷 55-69页

作者： Ahmed Fahd Alex Baranovsky Charles Dubois jamal Chaouki sherif Elbasuney shady shokry Chemical Engineering Department Ecole Polytechnique de MontrealMontrealH3C 3A7Canada Energetic Materials and Nanotechnology Research Center Technical Research CenterCairo11765Egypt Mechanical and Mechatronics Engineering Department University of WaterlooOntarioN2L 3G1Canada Head of Nanotechnology Research Center Military Technical CollegeCairo11767Egypt Laser and Optoelectronics Research Center Technical Research CenterCairo11765Egypt

Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(IsP), volumetric impulse(IsV), as well as normalized energy were found to increase notably with CNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and IsPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications.

关键词： Nanothermites Graphene oxide Reduced graphene oxide Carbon nano material Oxygenated salts Laser ignition Computational fluid dynamics

New Enhanced Authentication Protocol for Internet of Things

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Big Data Mining and Analytics 2021年第1期4卷 1-9页

作者： Mourade Azrour jamal Mabrouki Azedine Guezzaz Yousef Farhaoui IDMs Team Department of Computer ScienceFaculty of Sciences and TechniquesMoulay Ismail UniversityErrachidia 52000Morocco Laboratory of spectroscopy Molecular ModelingMaterialsNanomaterialWater and EnvironmentCERNE2DFaculty of ScienceMohammed V University in RabatRabat 10000Morocco Department of Computer science and Mathematics High School of TechnologyCadi Ayyad UniversityMarrakesh 40000Morocco

Internet of Things(IoT)refers to a new extended network that enables to any object to be linked to the Internet in order to exchange data and to be controlled ***,due to its multiple advantages,the IoT is useful in many areas like environment,water monitoring,industry,public security,medicine,and so *** covering all spaces and operating correctly,the IoT benefits from advantages of other recent technologies,like radio frequency identification,wireless sensor networks,big data,and mobile ***,despite of the integration of various things in one network and the exchange of data among heterogeneous sources,the security of user’s data is a central *** this reason,the authentication of interconnected objects is received as an interested *** 2012,Ye et *** a new authentication and key exchanging protocol for Internet of things ***,we have proved that their protocol cannot resist to various *** this paper,we propose an enhanced authentication protocol for ***,we present the comparative results between our proposed scheme and other related ones.

关键词： authetication Internet of Things(IoT) sensor security authorization

Nonalcoholic fatty liver disease and mitochondrial dysfunction

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World Journal of Gastroenterology 2008年第2期14卷 193-199页

作者： Yongzhong Wei R scott Rector John P Thyfault jamal A Ibdah Division of Gastroenterology and Hepatology Harry S. Truman VA MedicalCenter Columbia MO 65212 United States Division of Gastroenterology and Hepatology Department of Nutritional Sciences University of Missouri-Columbia Harry s. Truman VA Medical Center Columbia MO65212 United States

Nonalcoholic fatty liver disease (NAFLD) includes hepatic steatosis, nonalcoholic steatohepatitis (NAsH), fibrosis, and cirrhosis. NAFLD is the most common liver disorder in the United states and worldwide. Due to the rapid rise of the metabolic syndrome, the prevalence of NAFLD has recently dramatically increased and will continue to increase. NAFLD has also the potential to progress to hepatocellular carcinoma (HCC) or liver failure. NAFLD is strongly linked to caloric overconsumption, physical inactivity, insulin resistance and genetic factors. Although significant progress in understanding the pathogenesis of NAFLD has been achieved in years, the primary metabolic abnormalities leading to lipid accumulation within hepatocytes has remained poorly understood. Mitochondria are critical metabolic organelles serving as "cellular power plants". Accumulating evidence indicate that hepatic mitochondrial dysfunction is crucial to the pathogenesis of NAFLD. This review is focused on the significant role of mitochondria in the development of NAFLD.

关键词： Nonalcoholic fatty liver disease Mitochondria Fatty acid oxidation Liver

FPGA Implementation of Elliptic-Curve Diffie Hellman Protocol

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Computers, Materials & Continua 2022年第10期73卷 1879-1894页

作者： sikandar Zulqarnain Khan sajjad shaukat jamal Asher sajid Muhammad Rashid Department of Aeronautical Engineering Estonian Aviation AcademyTartu61707Estonia Department of Mathematics College of ScienceKing Khalid UniversityAbha61413Saudi Arabia Department of Electrical Engineering Bahria UniversityIslamabad44000Pakistan Department of Computer Engineering Umm Al-Qura UniversityMakkah21955Saudi Arabia

This paper presents an efficient crypto processor architecture for key agreement using ECDH(Elliptic-curve Diffie Hellman)protocol over GF2163.The composition of our key-agreement architecture is expressed in consisting of the following:(i)Elliptic-curve Point Multiplication architecture for public key generation(DEsIGN-I)and(ii)integration of DEsIGN-I with two additional routing multiplexers and a controller for shared key generation(DEsIGN-II).The arithmetic operators used in DEsIGN-I and DEsIGNII contain an adder,squarer,a multiplier and inversion.A simple shift and add multiplication method is employed to retain lower hardware ***,an essential inversion operation is operated using the Itoh-Tsujii algorithm with similar hardware resources of used squarer and multiplier *** proposed architecture is implemented in a Verilog *** implementation results are given on a Xilinx Virtex-7 FPGA(field-programmable gate array)*** DEsIGN-I and DEsIGN-II over GF2163,(i)the utilized slices are 3983 and 4037,(ii)the time to compute one public key and a shared secret is 553.7μs and 1170.7μs and(iii)the consumed power is 29μW and 57μ***,the achieved area optimized and power reduced results show that the proposed ECDH architecture is a suitable alternative(to generate a shared secret)for the applications that require low hardware resources and power consumption.

关键词： Elliptic curve cryptography point multiplication key-agreement diffie hellman area optimized architecture FPGA