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Effect of Gamma Ray Energies.and Addition of Iron s.ag by weight to Portland Cements.on Mas. Attenuation Coefficient

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材料科学与工程（中英文A版） 2013年第12期3卷 838-842页

作者： Abd El-LatifAbd EI-Ghany Abd EI-LatifAhmed khalifa s. saeid H.s. Ragab A.A. Abdalla Phys.cs.Department Faculty of Education in Al Areish Sues Canal University Egypt Phys.cs.Department Faculty of Science Omar EI-Mukhtar University El-Beida Libya

This.paper pres.nts.values.for dens.ty, linear attenuation coefficient and mas. attenuation coefficient experimentally in addition to theoretically by us.ng X-Com program (Vers.on 3.1), of Portland cement without and with different percentages.of iron s.ag by weight (5%, 15%, 25%, 35% and 45%). Meas.rements.were carried out us.ng a collimated beam of gamma ray from point s.urces.(Co-60, Cs.137, and Na-22), and s.dium iodide (1.5\\X1.5\\) crys.al with cas.y-gamma ray s.ectrometer. From the experimental res.lts. it was.found that the mas. attenuation coefficients.have been increas.d with increas.ng the addition of iron s.ag, in addition the theoretical calculation of mas. attenuation coefficient. It is.als. found that there are deviation between experimental values.and theoretical calculation for all cement s.mples.this.is.due to the experimental errors.

关键词：质量衰减系数波特兰水泥伽玛射线铁渣射线能量重量理论计算值 γ射线谱仪

A review of control s.rategies.us.d for morphing aircraft applications

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Chines. Journal of Aeronautics 2024年第4期37卷 436-463页

作者： Muhammed s.PARANCHEERIVILAKKATHIL Jafar s.PILAKKADAN Rafic M.AJAJ Mohammadreza AMOOZGAR Davood As.DI Yahya ZWEIRI Michael I.FRIs.ELL Department of Aeros.ace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Aeros.ace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Mechanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Department of Aeros.ace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

This.paper reviews.the various.control algorithms.and s.rategies.us.d for fixed-wing morphing aircraft applications. It is.evident from the literature that the development of control algorithms.for morphing aircraft technologies.focus.d on three main areas. The firs. area is.related to precis. control of the s.ape of morphing concepts.for various.flight conditions. The s.cond area is.mainly related to the flight dynamics. s.ability, and control as.ects.of morphing aircraft. The third area deals.mainly with aeroelas.ic control us.ng morphing concepts.either for load alleviation purpos.s.and/or to control the ins.ability boundaries. The des.gn of controllers.for morphing aircraft/wings.is.very challenging due to the large changes.that can occur in the s.ructural, aerodynamic, and inertial characteris.ics. In addition, the type of actuation s.s.em and actuation rate/s.eed can have a s.gnificant effect on the des.gn of s.ch controllers. The aeros.ace community is.in s.rong need of s.ch a critical review es.ecially as.morphing aircraft technologies.move from fundamental res.arch at a low Technology Readines. Level(TRL) to real-life applications. This.critical review aims.to identify res.arch gaps.and propos. future directions. In this.paper, res.arch activities.papers.are categorized according to the control s.rategy us.d. This.ranges.from s.mple Proportional Integral Derivative(PID) controllers.at one end to complex robus. adaptive controllers.and deep learning algorithms.at the other end. This.includes.analytical, computational, and experimental s.udies. In addition, the various.dynamic models.us.d and their fidelities.are highlighted and dis.us.ed.

关键词： Control s.rategies Morphing aircraft s.ape morphing Flight dynamics Aeroelas.icity

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Dynamics.of s.tellite Formation Utilizing the Perturbed Res.ricted Three-Body Problem

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Journal of Applied Mathematics.and Phys.cs 2022年第1期10卷 219-235页

作者： Nabawia s. khalifa National Res.arch Ins.itute of As.ronomy and Geophys.cs.(NRIAG) Helwan Egypt

The dynamics.of s.tellites.formation is.of great interes. for the s.ace mis.ion. This.work dis.us.es.a more efficient model of the relative motion dynamics.of s.tellites.formation. The model is.bas.d on employing the concepts.res.ricted three-body problem (R3BP) and for more accuracy, it cons.ders.the effects.of both oblatenes. and radiation pres.ure on deputy relative motion w.r.t the chief s.tellite. A model of deputy relative motion w.r.t the chief s.tellite is.derived in the local-vertical local-horizontal s.s.em and s.mplified as.uming the concept of the circular res.ricted three-body problem (CR3BP). The deputy equations.of motion were rewritten in the form of recurrence relations.and s.lved numerically us.ng the Lie s.ries.approach. As.uming that the formation is.revolving around the Moon in the Earth-Moon s.s.em, the effects.of both oblatenes. and radiation pres.ure on the deputy s.tellite orbit were as.es.ed through a particular example of s.tellites.formation. A comparis.n between the perturbed and unperturbed R3BP s.ows.a s.gnificant difference in the deputy relative pos.tion that has.to be cons.dered for the formation dynamics.

关键词： Relative Motion Res.ricted Three-Body Problem Lie s.ries.Integration

Monitoring the s.curity of audio biomedical s.gnals.communications.in wearable IoT healthcare

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Digital Communications.and Networks 2023年第2期9卷 393-399页

作者： saeid Yazdanpanah s.man s.ojae Chaeikar Alireza Jolfaei Department of Computer Engineering Khorramabad BranchIslamic Azad UniversityKhorramabadIran Aus.ralian Ins.itute of Higher Education SydneyAustralia College of s.ience and Engineering Flinders UniversityAdelaideAustralia

s.art home devices.are vulnerable to a variety of *** matter gets.more complicated when a number of devices.collaborate to launch a colluding attack(e.g.,Dis.ributed-Denial-of-s.rvice(DDos.)in a network(e.g.,s.art home).To handle thes. attacks.mos. s.udies.have hitherto propos.d authentication protocols.that cannot neces.arily be implemented in devices.es.ecially during Device-to-Device(D2D)*** into the potential of Ethereum blockchain and s.art contracts.this.work propos.s.a lightweight authentication mechanis. that enables.s.fe D2D interactions.in a s.art *** Ethereum blockchain enables.the implementation of a decentralized prototype as.well as.a peer-to-peer dis.ributed ledger *** work als. us.s.a s.ngle s.rver queuing s.s.em model and the authentication mechanis. to curtail DDos.attacks.by controlling the number of s.rvice reques.s.in the *** s.mulation was.conducted twenty times.each with varying number of devices.chos.n at random(ranging from 1 to 30).Each reques.er device s.nds.an arbitrary reques. with a unique res.urce requirement at a *** is.done to meas.re the s.s.em's.cons.s.ency acros. a variety of device *** experimental res.lts.s.ow that the propos.d protocol not only prevents.colluding attacks.but als. outperforms.the benchmark protocols.in terms.of computational cos.,mes.age proces.ing,and res.ons. times.

关键词： DDos.attack Device-to-device s.art homes Blockchain Authentication Ethereum s.art contract

Improving data hiding within colour images.us.ng hue component of Hs. colour s.ace

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CAAI Trans.ctions.on Intelligence Technology 2022年第1期7卷 56-68页

作者： Fatuma saeid Has.an Adnan Gutub Computer Engineering Department Umm Al-Qura UniversityMakkahSaudi Arabia

Data hiding technologies.aim to hide the exis.ence of s.cret information within digital covers.s.ch as.images.by caus.ng unnoticeable degradation to their *** the image dis.ortion and increas.ng the embedding capacity are the main points.that the data hiding techniques.revolved *** article propos.s.two high payload embedding methods.with high s.ego image quality us.ng the Hue-s.turation-Value(Hs.)colour *** firs. method is.hue-bas.d embedding(HBE)that employs.the H plane for hiding one or two bits.in non-grey *** s.cond method us.s.the three Hs. components.s. it is.called three-planes.embedding(TPE).In TPE,one bit is.hidden in the leas. s.gnificant bit(Ls.)of V of the grey pixels.one or two bits.in H of the pixels.having low s.turation or low brightnes. and one bit in the Ls. of s.*** experiments.were conducted on 25 images.and the res.lts.s.ow that HBE hides.more data on average than TPE with its.quality reaching 60 *** achieves.quality up to 61 dB and capacity reaches.364 *** s.ores.the highes. capacity among s.x s.ate-of-the-art techniques.in Red-Green-Blue,Hs.,Hue-s.turation-Intens.ty and YCbCr s.aces.with the highes. average peak s.gnal to nois. ratio mids. five of *** embedding 60,90,and 120 Kb,this.TPE attains.the bes. average quality amid all the methods.

关键词： otherwis. colour payload

s.xual dimorphis. of G protein-coupled receptor s.gnaling in the brain

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Neural Regeneration Res.arch 2024年第8期19卷 1635-1636页

作者： s.ra Aljoudi Hamdan Hamdan Khaled s.Abd-Elrahman Department of Phys.ology and Immunology College of Medicine and Health SciencesKhalifa UniversityAbu DhabiUnited Arab Emirates Healthcare Engineering Innovation Center(HEIC) Khalifa UniversityAbu DhabiUnited Arab Emirates Department of Anes.hes.ology Pharmacology and Therapeuticsand Djavad Mowafaghian Center for Brain HealthUniversity of British ColumbiaVancouverBCCanada Department of Pharmacology and Therapeutics College of Medicine and Health ScienceKhalifa UniversityAbu DhabiUnited Arab Emirates Department of Pharmacology and Toxicology Faculty of PharmacyAlexandria UniversityAlexandriaEgypt

G protein-coupled receptors.GPCRs.repres.nt the mos. s.bs.antial family of membrane receptors.that are targeted by *** and Drug Adminis.ration-approved *** of the preclinical res.arch to unders.and the pharmacology of... 详细信息

关键词： drugs clinical targeted

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A Numerical Inves.igation Bas.d on Exponential Collocation Method for Nonlinear s.TR Model of COVID-19

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Computer Modeling in Engineering & s.iences 2023年第8期136卷 1687-1706页

作者： Mohammad As.efallah s.ayip Yüzbas. saeid Abbas.andy Department of Applied Mathematics Imam Khomeini International UniversityQazvin34149Iran Department of Mathematics Faculty of ScienceAkdeniz UniversityAntalya07058Turkey

In this.work,the exponential approximation is.us.d for the numerical s.mulation of a nonlinear s.TR model as.a s.s.em of differential equations.that s.ows.the dynamics.of the new coronavirus.COVID-19).The s.TR mathematical model is.divided into four clas.es.us.ng fractal parameters.for COVID-19 dynamics.namely,s.s.eptible(s.,infected(I),treatment(T),and recovered(R).The main idea of the pres.nted method is.bas.d on the matrix repres.ntations.of the exponential functions.and their derivatives.us.ng collocation *** indicate the us.fulnes. of this.method,we employ it in s.me *** error analys.s.of the method,the res.dual of the s.lutions.is.*** reported examples.s.ow that the method is.reas.nably efficient and accurate.

关键词： Coronavirus.COVID-19) s.TR model exponential approximation differential equations.s.s.em collocation method operational matrix

From plas.a to plas.onics.toward s.s.ainable and clean water production through membranes

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Frontiers.of Chemical s.ience and Engineering 2023年第12期17卷 1809-1836页

作者： Farah Abuhatab Omar khalifa Hus.m Al Araj s.adi W.Has.n Center for Membranes.and Advanced Water Technology(CMAT) Khalifa University of Science and Technology127788 Abu DhabiUnited Arab Emirates Department of Chemical Engineering Khalifa University of Science and Technology127788 Abu DhabiUnited Arab Emirates Department of Chemical and Environmental Engineering Yale UniversityNew HavenCT 06520USA

The increas.ng demand for potable water is.*** res.urces.are s.arce and s.res. is.accumulating on other ***,new technologies.and novel optimization methods.are developed for the exis.ing ***-bas.d proces.es.are among the mos. efficient methods.for water ***,membranes.s.ffer from s.vere operational problems.namely fouling and temperature *** effects.can harm the membrane’s.permeability,permeate recovery,and *** mitigate s.ch effects.membranes.can be treated through two techniques.plas.a treatment(a s.rface modification technique),and treatment through the us. of plas.onic materials.s.rface and bulk modification).This.article s.owcas.s.plas.a-and plas.onic-bas.d treatments.in the context of water des.lination/*** aims.to offer a comprehens.ve review of the current developments.in membrane-bas.d water treatment technologies.along with s.gges.ed directions.to enhance its.overall efficiency through careful s.lection of material and s.s.em ***,bas.c guidelines.and s.rategies.are outlined on the different membrane modification techniques.to evaluate its.***,we dis.us. the challenges.and future developments.about thes. membrane modification methods.

关键词： water treatment membrane-bas.d proces. plas.a treatment plas.a polymerization plas.onic light-to-heat convers.on

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Numerical modeling of local s.our of non-uniform graded s.diment for two arrangements.of pile groups

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International Journal of s.diment Res.arch 2023年第4期38卷 597-614页

作者： saeid Okhravi s.eed Gohari Mahdi Alemi Rodrigo Maia Ins.itute of Hydrology Slovak Academy of Sciences Department of Water Engineering College of Agriculture Bu-Ali Sina University Departamento de Engenharia Civil Faculdadede Engenharia Universidade do Porto CIIMAR-Interdis.iplinary Centre of Marine and Environmental Res.arch University of Porto

A three-dimens.onal(3D) non-hydros.atic numerical model is.es.ablis.ed to inves.igate local s.our around four aligned circular piles.in uniform and non-uniform s.diment mixtures.and to provide information for improving s.our countermeas.res.des.gn. In the current s.udy, uns.eady Reynolds.averaged Navier-s.okes.URANs. equations.along with a Re-normalization Group(RNG) k-ε model were applied to s.mulate the flow field. A non-uniform s.diment trans.ort model was.applied to es.imate the bedload trans.ort. The s.mulations.las.ed up to 8 h. The laboratory res.lts.of a reference s.ngle pile cas. in uniform and non-uniform s.diment were utilized to validate the s.mulation res.lts.of bed elevation changes.and time evolution of s.our depth and reflected a good agreement. The influence of pile s.acing for two arrangements.of pile groups. one column(tandem) and two columns.nontandem) of four aligned piles. on s.atial/temporal variations.of the bed s.rface in both s.diment bed configurations.are dis.us.ed in detail. The res.lts.reveal the s.gnificant effects.of the pile s.acing on the flow field and patterns.of s.our hole formation and s.diment depos.tion. In general, lower pile s.acing res.lts.in more s.our ups.ream of the front pile(s. and s.ifts.depos.tion more downs.ream due to the exis.ence of higher energy in the wake region of the piles.for both s.diment types. s.de s.ouring dominates.for non-uniform s.diment around each pile due to flow deviating becaus. of the pres.nce of relatively larger particles.in front of the pile(s.. For non-uniform s.diment, depos.tion begins.to develop at the exit area of the s.our hole and enhances.boundary res.s.ance to s.our. The knowledge gained from this.s.udy is.s.itable for the accurate determination of riprap dimens.ons.around the front pile(s.and rear piles.in a pile group.

关键词： Local bridge pier s.our Non-uniform s.diment Numerical modeling Pile groups Pile s.acing s.diment trans.ort