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Improving electrical,optical and radiation shielding properties of polyvinyl alcohol yttrium oxide composites

Journal of Rare earths 2023年第12期41卷 2002-2009,I0007页

作者： shams A.M.Issa D.e.Abulyazied Albandari W.Alrowaily H.A.saudi e.s.ali A.M.A.Henaish Hesham M.H.Zakaly Department of Physics Faculty of ScienceUniversity of TabukTabukSaudi Arabia Faculty of science Al-Azhar UniversityAssiut BranchAssiut71524Egypt Polymer Lab Department of PetrochemicalEgyptian Petroleum Research InstituteNasr CityCairoEgypt Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Physics Department Faculty of ScienceAl-Azhar University(Girls Branch)Nasr CityCairoEgypt Institute of Physics and Technology Ural Federal UniversityYekaterinburg620002Russia Physics Department Faculty of ScienceTanta UniversityTanta31527Egypt Istinye University Faculty of Engineering and Natural SciencesComputer Engineering DepartmentIstanbul34396Turkey

This research aims to study the impact of yttrium oxide on the radiation protection features of polyvinyl alcohol(PVA) for gamma shielding *** yttrium oxide(Y_(2)O_(3)) was instilled through the PVA matrix by different contents(x=0.1 wt%,0,3 wt%,0,7 wt%,0,9 wt%),The morphology of the prepared PVA/Y_(2)O_(3)composites was characterized using scanning electron microscopy(seM).The samples were investigated using absorption edge,transmittance spectra and dielectric *** transmittance and the bandgap energy decrease as the Y2O3content increases while there is an increase in ε’ and ε" as well as the ac conductivity with the content increment of Y_(2)O_(3)till 0.7 wt%.The te mperature dependence of the dc conductivity was measured for all samples in the range of 260-460 K,and it increases with the temperature *** correlate the electrical characteristics of the PVA/Y_(2)O_(3)composites with their structure and evaluate electrical properties with the help of equivalent circuit matching with the experimentally electrical response in the impedance spectrum,the radiation protection properties were also investigated to get the radiation shielding performance of these PVA/Y_(2)O_(3)composite films with varying Y_(2)O(3)*** linear attenuation coefficient(μ),half value layer(T_(0.5)),and mass attenuation coefficient(μm) were *** to all obtained data,PVA/Y_(2)O_(3)composite films with various percentages(0.1 wt%,0.3 wt%,0.7 wt%,0.9 wt%) can be used as a radiation shielding material.

关键词： Yttriumoxide/PVA electrical properties Optical properties Gamma shielding Rare earths

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Big data challenge for monitoring quality in higher education institutions using business intelligence dashboards

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Journal of electronic science and Technology 2024年第1期22卷 25-41页

作者： ali sorour Anthony s.Atkins Faculty of Digital TechnologyInnovationand BusinessStaffordshire UniversityStoke-on-TrentST42DEUnited Kingdom

As big data becomes an apparent challenge to handle when building a business intelligence(BI)system,there is a motivation to handle this challenging issue in higher education institutions(HeIs).Monitoring quality in HeIs encompasses handling huge amounts of data coming from different *** paper reviews big data and analyses the cases from the literature regarding quality assurance(QA)in *** also outlines a framework that can address the big data challenge in HeIs to handle QA monitoring using BI dashboards and a prototype dashboard is presented in this *** dashboard was developed using a utilisation tool to monitor QA in HeIs to provide visual representations of big *** prototype dashboard enables stakeholders to monitor compliance with QA standards while addressing the big data challenge associated with the substantial volume of data managed by HeIs’QA *** paper also outlines how the developed system integrates big data from social media into the monitoring dashboard.

关键词： Big data Business intelligence(BI) Dashboards Higher education(He) Quality assurance(QA) social media

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Genuine entanglement under squeezed generalized amplitude damping channels with memory

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Chinese Physics B 2024年第2期33卷 158-163页

作者： Mazhar ali Department of electrical engineering Faculty of EngineeringIslamic University MadinahMadinah 107Saudi Arabia

We study genuine entanglement among three qubits undergoing a noisy process that includes dissipation, squeezing,and decoherence. We obtain a general solution and analyze the asymptotic quantum states. We find that most of these asymptotic states can be genuinely entangled depending upon the parameters of the channel, memory parameter, and the parameters of the initial states. We study Greenberger–Horne–Zeilinger(GHZ) states and W states, mixed with white noise,and determine the conditions for them to be genuinely entangled at infinity. We find that for these mixtures, it is possible to start with a bi-separable state(with a specific mixture of white noise) and end with genuine entangled states. However, the memory parameter μ must be very high. We find that in contrast to the two-qubit case, none of the three-qubit asymptotic states for n → ∞ are genuinely entangled.

关键词： genuine entanglement squeezed thermal baths multipartite states

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5G Resource Allocation Using Feature selection and Greylag Goose Optimization Algorithm

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Computers, Materials & Continua 2024年第7期80卷 1179-1201页

作者： Amel ali Alhussan s.K.Towfek Department of Computer sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Computer science and Intelligent systems Research Center BlacksburgVA 24060USA

In the contemporary world of highly efficient technological development,fifth-generation technology(5G)is seen as a vital step forward with theoretical maximum download speeds of up to twenty gigabits per second(Gbps).As far as the current implementations are concerned,they are at the level of slightly below 1 Gbps,but this allowed a great leap forward from fourth generation technology(4G),as well as enabling significantly reduced latency,making 5G an absolute necessity for applications such as gaming,virtual conferencing,and other interactive electronic *** of this change are not limited to connectivity alone;it urges operators to refine their business strategies and offers users better and improved digital *** essential factor is optimization and the application of artificial intelligence throughout the general arrangement of intricate and detailed 5G *** Binary Greylag Goose Optimization(bGGO)to achieve a significant reduction in the feature set while maintaining or improving model performance,leading to more efficient and effective 5G network management,and Greylag Goose Optimization(GGO)increases the efficiency of the machine ***,the model performs and yields more accurate *** work proposes a new method to schedule the resources in the next generation,5G,based on a feature selection using GGO and a regression model that is an ensemble of K-Nearest Neighbors(KNN),Gradient Boosting,and extra Trees *** ensemble model shows better prediction performance with the coefficient of determination R squared value equal *** proposed framework is supported by several statistical analyses,such as theWilcoxon signed-rank *** of the benefits of this study are the introduction of new efficient optimization algorithms,the selection of features and more reliable ensemble models which improve the efficiency of 5G technology.

关键词： Optimization ensemble learning 5G technology artificial intelligence greylag goose optimization ANOVA test

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enhancing Renewable energy Integration:A Gaussian-Bare-Bones Levy Cheetah Optimization Approach to Optimal Power Flow in electrical Networks

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Computer Modeling in engineering & sciences 2024年第8期140卷 1339-1370页

作者： ali s.Alghamdi Mohamed A.Zohdy saad Aldoihi Department of electrical engineering College of EngineeringMajmaah UniversityAl-Majmaah11952Saudi Arabia electrical and Computer engineering Department Oakland UniversityRochesterMI48309USA Institute of earth and space science King Abdulaziz City for Science and Technology(KACST)Riyadh11442Saudi Arabia Computer science and systems engineering Institute Polytechnique de ParisPalaiseau CedexFrance

In the contemporary era,the global expansion of electrical grids is propelled by various renewable energy sources(Ress).efficient integration of stochastic Ress and optimal power flow(OPF)management are critical for network *** study introduces an innovative solution,the Gaussian Bare-Bones Levy Cheetah Optimizer(GBBLCO),addressing OPF challenges in power generation systems with stochastic *** primary objective is to minimize the total operating costs of Ress,considering four functions:overall operating costs,voltage deviation management,emissions reduction,voltage stability index(VsI)and power loss ***,a carbon tax is included in the objective function to reduce carbon *** scrutiny,using modified Ieee 30-bus and Ieee 118-bus systems,validates GBBLCO’s superior performance in achieving optimal *** results demonstrate GBBLCO’s efficacy in six optimization scenarios:total cost with valve point effects,total cost with emission and carbon tax,total cost with prohibited operating zones,active power loss optimization,voltage deviation optimization and enhancing voltage stability index(VsI).GBBLCO outperforms conventional techniques in each scenario,showcasing rapid convergence and superior solution ***,GBBLCO navigates complexities introduced by valve point effects,adapts to environmental constraints,optimizes costs while considering prohibited operating zones,minimizes active power losses,and optimizes voltage deviation by enhancing the voltage stability index(VsI)*** research significantly contributes to advancing OPF,emphasizing GBBLCO’s improved global search capabilities and ability to address challenges related to local *** emerges as a versatile and robust optimization tool for diverse challenges in power systems,offering a promising solution for the evolving needs of renewable energy-integrated power grids.

关键词： Renewable energy integration optimal power flow stochastic renewable energy sources gaussian-bare-bones levy cheetah optimizer electrical network optimization carbon tax optimization

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Heat transfer analysis in particle-laden flows using the immersed boundary method

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Particuology 2024年第7期90卷 394-403页

作者： ali Abbas Zaidi Department of Mechanical engineering University of Manitoba75A Chancellors CircleWinnipegR3T 5V6Canada

This paper investigates an efficient immersed boundary method(IBM)for multiple-core CPU machines with local grid refinement for the calculation of heat transfer between fluids and finite-sized *** fluid momentum equations are solved by using the fractional step method,while the energy equation is solved by employing the second-order Adams-Bashforth *** efficient load balancing between the CPU cores,the coupling between particles and fluid is obtained by applying the body force in the fluid equations,which depends on the solid volume fraction of particles contained in each grid cell,and then by linearly interpolating the particle temperature and velocity on the fluid grid cell(in place of the delta function commonly used in literature).several test cases from the literature are studied,and good agreement is observed between the simulation results and the ***,a scaling study on multiple core machines is performed,demonstrating the proposed IBM's capabilities for a significant reduction in processing time.

关键词： Heat transfer Immersed boundary method Particle resolved direct numerical simulations Fluid solid interactions

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simulation of the deformable lateral boundaries in biaxial test using DeM

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Particuology 2024年第5期88卷 161-175页

作者： ali Momeni Barry Clarke Yong sheng ali Hassanpour WsP 3 Wellington PlaceLeedsLS1 4APUK Hull University HullHU6 7RXUK school of Civil engineering University of LeedsLeedsLS2 9JTUK school of Computer science University of HullHullHU6 7RXUK school of Chemical and Process engineering University of LeedsLeedsLS2 9JTUK

Applying the discrete element method(DeM)in soil mechanics can provide abundant information at the particle-scale and facilitates illustration of the macro-mechanical behaviour of soils based on the inter-particle *** triaxial test is one of the most common laboratory methods to study the macro-mechanical behaviour of particulate materials such as ***,many problems in geotechnical design can be assumed and simplified as a plane strain *** a biaxial test can be conducted to reproduce the macro-mechanical behaviour of soil,where the sample is enclosed by two horizontal rigid platens and a vertical latex membrane,which is a deformable continuous element and allows the enclosed specimen to deform freely while maintaining confining stress during *** paper presents an algorithm to represent physical and mechanical characteristics of latex membrane in the 2D DeM simulation of biaxial test using the PFC^(2D) *** investigate the impact of the lateral boundary conditions on the micro-macro mechanical behaviours of soil samples,two sets of DeM biaxial tests are conducted,*** rigid and deformable lateral boundary *** DeM modeling results indicate that the lateral boundary conditions have a significant effect on the micro-scale fabric properties,thickness and inclination of the shear *** comparison between these two simulations also demonstrates that the lateral boundary conditions play a major role in the peak and post-peak stress-strain behaviours as well as the dilation and critical state behaviours of granular soils.

关键词： Discrete element method Biaxial test Deformable boundaries shear band Critical state Fabric anisotropy Geometrical stability index

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sensing the heavy water concentration in an H_(2)O-D_(2)O mixture by solid-solid phononic crystals

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Chinese Physics B 2024年第4期33卷 493-498页

作者： Mohammadreza Rahimi ali Bahrami Optoelectronic and Nanophotonics Research Laboratory(ONRL) Faculty of Electrical EngineeringSahand University of TechnologyTabrizIran

A new method based on phononic crystals is presented to detect the concentration of heavy water(D_(2)O)in an H_(2)O-D_(2)O *** have been obtained and analyzed in the concentration range of 0%-10%and 90%-100%D_(2)O.A proposed structure of tungsten scatterers in an aluminum host is *** order to detect the target material,a cavity region is considered as a sound wave resonator in which the target material with different concentrations of D_(2)O is *** changing the concentration of D_(2)O in the H_(2)O-D_(2)O mixture,the resonance frequency undergoes a frequency *** 1%change in D_(2)O concentration in the H_(2)O-D_(2)O mixture causes a frequency change of about 120 *** finite element method is used as the numerical method to calculate and analyze the natural frequencies and transmission spectra of the proposed *** performance evaluation index shows a high Q factor up to 1475758 and a high sensitivity up to 13075,which are acceptable values for sensing *** other figures of merit related to the detection performance also indicate high-quality performance of the designed sensor.

关键词： phononic crystals sensor H_(2)O-D_(2)O mixture cavity

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Defining failure of endoluminal biliary drainage in the era of endoscopic ultrasound and lumen apposing metal stents

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World Journal of Gastroenterology 2024年第29期30卷 3534-3537页

作者： Faisal s ali sushovan Guha Department of Gastroenterology Hepatologyand NutritionUniversity of Texas Health Science Center at HoustonHustonTX 77054United States Department of Clinical sciences Tilman J.Fertitta Family College of MedicineUniversity of HoustonHoustonTX 77204United States

The role of endoscopy in pathologies of the bile duct and gallbladder has seen notable advancements over the past two *** advancements in stent technology,such as the development of lumen-apposing metal stents,and adoption of endoscopic ultrasound and electrosurgical principles in therapeutic endoscopy,what was once considered endoscopic failure has transformed into failure of an approach that could be salvaged by a second-or third-line endoscopic *** of these advancements in routine patient care will require formal training and multidisciplinary acceptance of established techniques and collaboration for advancement of experimental techniques to generate robust evidence that can be utilized to serve patients to the best of our ability.

关键词： endoscopic ultrasound Guided biliary drainage Gallbladder Biliary obstruction Lumen-apposing metal stent

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experimental study on Heat storage Properties Comparison of Paraffin/Metal Foams Phase Change Material Composites

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Journal of Thermal science 2024年第2期33卷 469-478页

作者： Waqar AHMeD Abid HUssAIN Hanzla sHAHID Imran ali Hafiz Muhammad ali Department of Mechanical engineering University of Engineering and TechnologyTaxila47080Pakistan Department of Mechanical engineering Institute of Space TechnologyIslamabadPakistan Department of Mechanical Mechatronics and Manufacturing EngineeringUniversity of Engineering and Technology LahoreFaisalabad CampusPunjabPakistan Mechanical engineering Department King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Renewable energy and Power systems(IRC-RePs) King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia

Heat storage properties of phase change materials(PCMs) are essential characteristics that perform a key role in thermal heat energy storage *** thermal properties of PCMs can be improved by developing metal foam/PCM *** addition of metal foam in PCMs has a significant effect on the thermal characteristics of *** this paper,the heat storage properties of two different metal foam/PCM composites were experimentally *** behavior of paraffin in metal foam(copper and iron-nickel)/paraffin composites concerning pure paraffin at a constant heat flux of 1000 W/m^(2) in three directions simultaneously(x,y,and z) was *** was infiltrated into copper and iron-nickel foams to develop composite materials which resulted in enhancing the thermal conductivity of the paraffin.A comparative analysis is made on the heat storage properties of paraffin in copper and iron-nickel foams/paraffin *** temperature distribution during the phase transition process is experimentally *** comparison indicates that temperature uniformity in copper foam/paraffin composite is better than in iron-nickel foam/paraffin composite and pure paraffin at the same heat *** results show that at heat flux of 1000 W/m^(2),the heat storage time for copper foam/paraffin composite is 20.63% of that of iron-nickel foam/paraffin composite.

关键词： heat storage capacity paraffin/metal foam composite temperature uniformity heat storage rate phase transition process

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