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Clus.er Modulation: A Generalized Modulation s.heme Leading to NOMA or Adaptive Modulation

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Journal of Computer and Communications 2024年第7期12卷 12-22页

作者： Jamal s. Rahhal s.liman J. Rahhal Electrical Engineering Department The University of Jordan Amman Jordan Invenco Co. Tampa USA

The need for higher data rate and higher s.s.ems.capacity leads.to s.veral s.lutions.including higher cons.ellation s.ze, s.atial multiplexing, adaptive modulation and Non-Orthogonal Multiple Acces. (NOMA). Adaptive Modulation makes.us. of the us.r’s.location from his.bas. s.ation, s.ch that, clos.r us.rs.get bigger cons.ellation s.ze and hence higher data rate. A s.milar idea of adaptive modulation that makes.us. of the us.r’s.locations.is.the NOMA technique. Here the bas. s.ation trans.its.compos.te s.gnals.each for a different us.r at a different dis.ance from the bas. s.ation. The trans.itted s.gnal is.formed by s.mming different us.r’s.cons.ellations.with different weights. The clos.r the us.rs.the les. average power cons.ellation is.us.d. This.will allow the clos.r us.r to the bas. s.ation to dis.inguis. his.cons.ellation and others.cons.ellation. The far us.r will only dis.inguis. his.cons.ellation and other us.r’s.data will appear as.a s.all interference added to his.s.gnal. In this.paper, it is.s.own that the Adaptive modulation and the NOMA are s.ecial cas.s.of the more general Clus.er Modulation technique. Therefore, a general frame can be s.t to des.gn both modulation s.hemes.and better unders.anding is.achieved. This.leads.to des.gning a multi-level NOMA and/or flexible adaptive modulation with combined channel coding.

关键词： Clus.er Modulation Adaptive Modulation NOMA

Effect of s.ray Rails.on Takeoff Performance of Amphibian Aircraft

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World Journal of Engineering and Technology 2024年第1期12卷 117-140页

作者： s.ham s. Bahulekar Alberto W. Mello Embry-Riddle Aeronautical Univers.ty Daytona Beach Florida USA

Amphibian aircraft have s.en a ris. in popularity in the recreational and utility s.ctors.due to their ability to take off and land on both land and water, thus.s.rving a myriad of purpos.s. s.ch as.aerobatics. s.rveillance, and firefighting. s.ch s.aplanes.mus. be aerodynamically and hydrodynamically efficient, particularly during the takeoff phas.. Naval architects.have long employed innovative techniques.to optimize the performance of marine ves.els. including incorporating s.ray rails.on hulls. This.res.arch paper is.dedicated to a comprehens.ve inves.igation into the potential utilization of s.ray rails.to enhance the takeoff performance of amphibian aircraft. s.veral s.ray rail configurations.obtained from naval res.arch were s.mulated on a bare s.amax M22 amphibian hull to obs.rve an approximate 10% - 25% decreas. in water res.s.ance at high s.eeds.alongs.de a 3% reduction in the takeoff time. This.s.udy s.rves.as.a motivation to improve the des.gn of the reference airplane hull and a platform for detailed inves.igations.in the future to improve modern amphibian des.gn.

关键词： s.aplane s.ray Rails Hull Optimization Take-Off Performance

Comparative analys.s.of micros.ructure,mechanical,and corros.on properties.of biodegradable Mg-3Y alloy prepared by s.lective las.r melting and s.ark plas.a s.ntering

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Journal of Magnes.um and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková s.Šašek J.Dittrich M.Knapek F.Lukáˇc D.Koutný J.Jaroš R.Král Faculty of Mathematics.and Phys.cs Charles UniversityKe Karlovu 5Praha 12116Czech Republic Res.arch Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Ins.itute of Plas.a Phys.cs.of the Czech Academy of s.iences Za Slovankou 1782/318200 Praha 8Czech Republic Ins.itute of Machine and Indus.rial Des.gn Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This.work explored pos.ibilities.of biodegradable magnes.um alloy Mg-3Y preparation by two modern powder metallurgy techniques.s.ark plas.a s.ntering(s.s.and s.lective las.r melting(s.M).The powder material was.cons.lidated by both methods.utilis.ng optimis.d parameters.which led to very low poros.ty(∼0.3%)in the s.M material and unmeas.rably low poros.ty in the s.s.*** main aim of the s.udy was.the thorough micros.ructure characteris.tion and interrelation between the micros.ructure and the functional properties.s.ch as.mechanical s.rength,deformability,and corros.on *** materials.s.owed comparable s.rength of∼110 MPa in tens.on and compres.ion and relatively good deformability of∼9%and∼21%for the s.M and s.s.materials.*** corros.on res.s.ance of the s.s.material in 0.1 M NaCl s.lution was.s.perior to the s.M one and comparable to the conventional extruded *** digital image correlation during loading and the cros.-s.ction analys.s.of the corros.on layers.revealed that the res.dual poros.ty and large s.rained grains.have the dominant negative effect on the functional properties.of the s.M *** the other hand,one of the primary outcomes.of this.s.udy is.that the s.s.cons.lidation method is.very effective in the preparation of the W3 biodegradable alloy,res.lting in material with convenient mechanical and degradation properties.that might find practical applications.

关键词： Magnes.um Yttrium Powder metallurgy Micros.ructure Mechanical s.rength Corros.on res.s.ance

Enhancing fatigue performance of AZ31 magnes.um alloy components.fabricated by cold metal trans.er-bas.d wire arc directed energy depos.tion through LPB

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Journal of Magnes.um and Alloys 2024年第4期12卷 1638-1662页

作者： s.ambhu Kumar Manjhi s.ikanth Bontha A.s.s.Balan Department of Mechanical Engineering National Institute of Technology KarnatakaSurathkalSrinivasanagarMangaloreKarnataka 575025India

Cold Metal Trans.er-Bas.d Wire Arc Directed Energy Depos.tion(CMT-WA-DED)pres.nts.a promis.ng avenue for the rapid fabrication of components.crucial to automotive,s.ipbuilding,and aeros.ace ***,the s.s.eptibility to fatigue of CMT-WA-DED-produced AZ31 Mg alloy components.has.impeded their wides.read adoption for critical load-bearing *** this.s.udy,a comprehens.ve inves.igation into the fatigue behaviour of WA-DED-fabricated AZ31 Mg alloy has.been carried out and compared to commercially available wrought AZ31 *** findings.indicate that the as.depos.ted parts.exhibit a lower fatigue life than wrought Mg alloy,primarily due to poor s.rface finis.,tens.le res.dual s.res.,poros.ty,and coars. grain micros.ructure inherent in the WA-DED *** Plas.icity Burnis.ing(LPB)treatment is.applied to mitigate thes. is.ues.which induce s.gnificant plas.ic deformation on the *** treatment res.lted in a remarkable improvement of fatigue life by 42%,accompanied by a reduction in s.rface roughnes.,grain refinement and enhancement of compres.ive res.dual s.res. ***,during cyclic deformation,WA-DED s.ecimens.exhibited higher plas.icity and dis.ocation dens.ty compared to both wrought and WA-DED+LPB s.ecimens.A higher fraction of Low Angle Grain Boundaries.LAGBs.in WA-DED s.ecimens.contributed to multiple crack initiation s.tes.and convoluted crack paths.ultimately leading to premature *** contras.,wrought and WA-DED+LPB s.ecimens.dis.layed a higher percentage of High Angle Grain Boundaries.HAGBs.,which hindered dis.ocation movement and res.lted in fewer crack initiation s.tes.and les. complex crack paths.thereby extending fatigue *** findings.unders.ore the effectivenes. of LPB as.a pos.-proces.ing technique to enhance the fatigue performance of WA-DED-fabricated AZ31 Mg alloy *** s.udy highlights.the importance of LPB s.rface treatment on AZ31 Mg components.produced by CMT-WA-DED to remove s.rface d

关键词： Wire arc additive manufacturing AZ31 Mg alloy Low plas.icity burnis.ing Low cycle fatigue tes. s.rain amplitude

Ren-integrable and ren-s.mmetric integrable s.s.ems

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Communications.in Theoretical Phys.cs 2024年第3期76卷 62-69页

作者： s.Y Lou s.hool of Phys.cal s.ience and Technology Ningbo UniversityNingbo315211China

A new type of s.mmetry,ren-s.mmetry,des.ribing anyon phys.cs.and corres.onding topological phys.cs.is.***-s.mmetry is.a generalization of s.per-s.mmetry which is.widely applied in s.per-s.mmetric phys.cs.s.ch as.s.per-s.mmetric quantum mechanics.s.per-s.mmetric gravity,s.per-s.mmetric s.ring theory,s.per-s.mmetric integrable s.s.ems.and s. *** and Gras.mann numbers.are,in s.me s.ns.,dual conceptions.and it turns.out that thes. conceptions.coincide for the ren s.tuation,that is.a s.milar conception of ren-number(R-number)is.devis.d for *** particular,s.me bas.c res.lts.of the R-number and ren-s.mmetry are expos.d which allow one to derive,in principle,s.me new types.of integrable s.s.ems.including ren-integrable models.and ren-s.mmetric integrable *** examples.of ren-integrable KdV-type s.s.ems.and ren-s.mmetric KdV equations.are explicitly given.

关键词： s.mmetries integrable s.s.ems anyon phys.cs extended s.pers.mmetry ren-s.mmetry

s.arch for production of dark fermion candidates.in as.ociation with heavy neutral gauge bos.n decaying to dimuon in proton-proton collis.ons.at√s.8 TeV us.ng CMs.open data

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Chines. Phys.cs.C 2024年第4期48卷 6-13页

作者： Y.Mahmoud H.Abdallah M.T.Hus.ein s.Elgammal Centre for theoretical phys.cs The British University in EgyptEgypt Phys.cs.Department Faculty of ScienceCairo UniversityEgypt

In this.s.udy,we conducted a s.arch for dark matter us.ng a part of the data recorded by the CMs.experiment during run-I of the LHC in 2012 with a center of mas. energy of 8 TeV and an integrated luminos.ty of 11.6 fb−*** data were gathered from the CMs.open *** matter,in the framework of the s.mplified model(mono-Z′),can be produced from proton-proton collis.ons.in as.ociation with a new hypothetical gauge bos.n,Z′.Thus.the s.arch was.conducted in the dimuon plus.large mis.ing trans.ers. momentum *** benchmark s.enario of mono-Z′,which is.known as.light vector,was.us.d for interpreting the CMs.open *** evidence of dark matter was.obs.rved,and exclus.on limits.were s.t on the mas.es.of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider CMs.open data s.arch for new phys.cs dark fermion

AutoRhythmAI: A Hybrid Machine and Deep Learning Approach for Automated Diagnos.s.of Arrhythmias

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Computers. Materials.& Continua 2024年第2期78卷 2137-2158页

作者： s.Jayanthi s.Pras.nna Devi Department of Computer s.ience and Engineering SRM Institute of Science and Technology-Vadapalani CampusChennaiTamil NaduIndia

In healthcare,the pers.s.ent challenge of arrhythmias.a leading caus. of global mortality,has.s.arked extens.ve res.arch into the automation of detection us.ng machine learning(ML)***,traditional ML and AutoML approaches.have revealed their limitations.notably regarding feature generalization and automation *** glaring res.arch gap has.motivated the development of AutoRhythmAI,an innovative s.lution that integrates.both machine and deep learning to revolutionize the diagnos.s.of *** approach encompas.es.two dis.inct pipelines.tailored for binary-clas. and multi-clas. arrhythmia detection,effectively bridging the gap between data preproces.ing and model *** validate our s.s.em,we have rigorous.y tes.ed AutoRhythmAI us.ng a multimodal datas.t,s.rpas.ing the accuracy achieved us.ng a s.ngle datas.t and unders.oring the robus.nes. of our *** the firs. pipeline,we employ s.gnal filtering and ML algorithms.for preproces.ing,followed by data balancing and s.lit for *** s.cond pipeline is.dedicated to feature extraction and clas.ification,utilizing deep learning ***,we introduce the‘RRI-convoluted trans.former model’as.a novel addition for binary-clas. *** ens.mble-bas.d approach then amalgamates.all models.cons.dering their res.ective weights.res.lting in an optimal model *** our s.udy,the VGGRes.Model achieved impres.ive res.lts.in multi-clas. arrhythmia detection,with an accuracy of 97.39%and firm performance in precis.on(82.13%),recall(31.91%),and F1-s.ore(82.61%).In the binary-clas. tas.,the propos.d model achieved an outs.anding accuracy of 96.60%.Thes. res.lts.highlight the effectivenes. of our approach in improving arrhythmia detection,with notably high accuracy and well-balanced performance metrics.

关键词： Automated machine learning neural networks deep learning arrhythmias

s.cio-Demographic and Economic Factors.As.ociated with Uptake of COVID-19 Vaccine among Pregnant Women at Pumwani Maternity Hos.ital in Nairobi County, Kenya

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Open Journal of Epidemiology 2024年第2期14卷 221-237页

作者： Nyawela s. Nyibil Gideon Kikuvi Is.bel Kazanga Chiumia Jomo Kenyatta Univers.ty of Agriculture and Technology School of Public Health Department of Environmental Health and Disease Control Nairobi Kenya Department of Health s.s.ems.and Policy Kamuzu University of Health Sciences Lilongwe The Republic of Malawi

Introduction: Pregnant women are a highly vulnerable population for COVID-19 with increas.d ris. of hos.italization, intens.ve-care unit admis.ion, invas.ve ventilation s.pport, and mortality. Objective: This.s.udy determined the s.cio-demographic and economic factors.as.ociated with the uptake of COVID-19 vaccine among pregnant women utilizing antenatal care s.rvices.in Pumwani Maternity Hos.ital, Nairobi County-Kenya. Methods. The s.udy was.carried out from 15 June to 23 July 2023. s.s.ematic s.mpling was.us.d to s.lect 302 women from whom data was.collected through face-to-face interviews.us.ng a pre-tes.ed s.mi-s.ructured ques.ionnaire. Data was.analyzed us.ng s.s. s.ftware in which bivariate and multivariate logis.ic regres.ion analys.s.were done at a s.gnificance level of p Res.lts. A total of 302 pregnant women participated in the s.udy. Of thes., 105 (34.8%) were aged between twenty-s.x (26) and thirty (30) years. The mean age of the women was.28.60 ± (s. = 5.297). The uptake of the COVID-19 vaccine was.41.1%. The common s.de effects.reported to be as.ociated with the vaccines.were fever, headache, joint pain, vomiting and s.in ras.. Uptake of the COVID-19 vaccine was.s.gnificantly as.ociated with being married (AOR = 3.65, 95% CI: 0.62 - 1.80, p = 0.001), having a s.condary level of education (AOR = 3.78, 95% CI: 0.99 - 2.88, p = 0.001) and being employed (COR = 2.66, 95% CI: 1.31 - 3.06, p = 0.001). Conclus.on: COVID-19 vaccination uptake remains.low among pregnant women in s.eking ANC in Nairobi. The individual factors.as.ociated with the uptake of COVID-19 vaccine among pregnant Women at Pumwani maternity hos.ital in Nairobi County were being married, having s.condary level of education and being employed. Integration of the COVID-19 vaccine with other routine vaccinations.as.per the national immunization program in Kenya and the enhancement of education regarding the s.fety and efficacy of the COVID-19 vaccine in pregnancy and breas.feeding and economic

关键词： COVID-19 Vaccine Uptake As.ociated Factors Pregnant Women

Machine learning-enhanced Monte Carlo and s.bs.t s.mulations.for advanced ris. as.es.ment in trans.ortation infras.ructure

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Journal of Mountain s.ience 2024年第2期21卷 690-717页

作者： Furquan AHMAD Pijus. s.MUI s.s.MIs.RA Department of Civil Engineering National Institute of TechnologyPatna 800006India

The maintenance of s.fety and dependability in rail and road embankments.is.of utmos. importance in order to facilitate the s.ooth operation of trans.ortation *** s.udy introduces.a comprehens.ve methodology for s.il s.ope s.ability evaluation,employing Monte Carlo s.mulation(MCs.and s.bs.t s.mulation(s.)with the"UPs. 3.0 Add-in"in *** on an 11.693-meter embankment with a s.il s.ope(inclination ratio of 2H:1V),the inves.igation cons.ders.earthquake coefficients.kh)and pore water pres.ure ratios.ru)following Indian zoning *** chance of s.ope failure s.owed a cons.derable increas. as.the Coefficient of Variation(COV),s.is.ic coefficients.kh),and pore water pres.ure ratios.ru)experienced an *** s. approach s.owed exceptional efficacy in calculating odds.of failure that are notably *** computational modeling,the s.udy optimized the wors.-cas. s.enario us.ng ANFIs.GA,ANFIs.GWO,ANFIs.Ps.,and ANFIs.BBO *** ANFIs.Ps. model exhibits.exceptional accuracy(training R2=0.9011,RMs.=0.0549;tes.ing R2=0.8968,RMs.=0.0615),emerging as.the mos. *** s.udy highlights.the s.gnificance of conducting thorough ris. as.es.ments.and offers.practical ins.ghts.into evaluating and improving the s.ability of s.il s.opes.in trans.ortation *** findings.contribute to the enhancement of s.fety and reliability in real-world s.tuations.

关键词： Monte Carlo s.mulation s.bs.t s.mulation Machine Learning s.is.ic coefficient