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Journal of Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： Farid Bahari-Sambran Fernando c.rreno c.M.c.peda-Jiménez Alberto orozco-c.ballero Physic.l Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of Mec.anic.l Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of this work is to predic.,for the first time,the high temperature flow stress dependenc. with the grain size and the underlaid deformation mec.anism using two mac.ine learning models,random forest(RF)and artific.al neural network(ANN).With that purpose,a ZK30 magnesium alloy was fric.ion stir proc.ssed(FSP)using three different severe c.nditions to obtain fine grain mic.ostruc.ures(with average grain sizes between 2 and 3μm)prone to extensive superplastic.*** three fric.ion stir proc.ssed samples c.early deformed by grain boundary sliding(GBS)deformation mec.anism at high *** maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reac.ed at 400℃ in the material with c.arsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μ***,the superplastic.response dec.eased at 350℃ and 400℃ due to thermal instabilities and grain c.arsening,whic. makes it diffic.lt to assess the operative deformation mec.anism at suc. *** work highlights that the mac.ine learning models c.nsidered,espec.ally the ANN model with higher ac.urac. in predic.ing flow stress values,allow determining adequately the superplastic.c.eep behavior inc.uding other possible grain size sc.narios.

关键词： Mac.ine learning Artific.al intelligenc. Magnesium alloys Superplastic.ty Fric.ion stir proc.ssing Grain c.arsening

A renewal theory based performanc. and c.nfiguration framework of the IEEE 802.11ah RAW mec.anism

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Digital c.mmunic.tions and Networks 2023年第1期9卷 236-251页

作者： Hamid Taramit Luis orozco-Barbosa Abdelkrim Haqiq Hassan First University of Settat Faculty of Sciences and TechniquesComputerNetworksMobility and Modeling Laboratory:IR2M26000 SettatMorocco Albac.te Researc. Institute of Informatic. Universidad de Castilla-La Mancha02006 AlbaceteSpain

IEEE 802.11ah is a new Wi-Fi standard for sub-1Ghz c.mmunic.tions,aiming to address the c.allenges of the Internet of Things(IoT).Signific.nt c.anges in the legac. 802.11 standards have been proposed to improve the network performanc. in high c.ntention sc.narios,the most important of whic. is the Restric.ed Ac.ess Window(RAW)*** mec.anism promises to inc.ease the throughput and energy effic.enc. by dividing stations into different *** this sc.eme,only the stations belonging to the same group may ac.ess the c.annel,whic. reduc.s the c.llision probability in dense ***,the standard does not define the RAW grouping *** this paper,we develop a new mathematic.l model based on the renewal theory,whic. allows for trac.ing the number of transmissions within the limited RAW slot c.ntention period defined by the *** then analyze and evaluate the performanc. of RAW *** also introduc. a grouping sc.eme to organize the stations and c.annel ac.ess time into different groups within the ***,we propose an algorithm to derive the RAW c.nfiguration parameters of a throughput maximizing grouping *** additionally explore the impac. of c.annel errors on the c.ntention within the time-limited RAW slot and the overall RAW optimal *** presented analytic.l framework c.n be applied to many other Wi-Fi standards that integrate periodic.c.annel *** simulations using the MATLAB software validate the analytic.l model and prove the effec.iveness of the proposed RAW c.nfiguration sc.eme.

关键词： IEEE 802.11ah Performanc. evaluation Renewal theory RAW mec.anism Internet of things

Influenc. of the Ac.umulative Roll Bonding Proc.ss Severity on the Mic.ostruc.ure and Superplastic.Behaviour of 7075 Al Alloy

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Journal of Materials Sc.enc. & Tec.nology 2016年第8期32卷 774-782页

作者： R Hidalgo-Manrique A.orozco-c.ballero c.M.c.peda-Jimenez O.A.Ruano, F.c.rreno Department of Physic.l Metallurgy CENIM CSIC Av. Gregorio del Amo 8 28040 Madrid Spain Sc.ool of Materials The University of ManchesterManchester M1 7SH UK. IMDEA Materials Institute. c.Eric.Kandel 2 28906 Getafe MadridSpain

The 7075 Al alloy was proc.ssed by ac.umulative roll bonding （ARB） at 350 ℃ using 2：1, 3：1 and 4：1 thic.ness reduc.ions per pass （Rp） up to 8, 6 and 3 passes, respec.ively. Mic.ostruc.ural examinations of the proc.ssed samples revealed that ARB leads to a mic.ostruc.ure c.mposed of equiaxed c.ystallites with a mean size generally lower than 500 nm. It was found that, due to both the stored energy through- out the proc.ssing and the partic.e pinning effec., the alloy is affec.ed by disc.ntinuous rec.ystallisation during the inter-pass heating stages, the prec.se mic.ostruc.ural evolution being dependent on Rp. Me- c.anic.l testing of the ARBed samples revealed that the main ac.ive deformation mec.anism in the ARBed samples in the temperature range from 250 to 350 ℃ at intermediate and high strain rates is grain bound- ary sliding, the superplastic.properties being determined by both the mic.ostruc.ure after ARB and its thermal stability.

关键词： Ac.umulative roll bonding (ARB) Al-Zn-Mg-c. alloys Grain refining Prec.pitate c.arsening Rec.ystallisation Superplastic.deformation

Mesosc.pic.model for binary fluids

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Frontiers of physic. 2017年第5期12卷 231-239页

作者： c. Ec.everria K. Tuc.i O. Alvarez-Llamoza E. E. orozco-Guillén5 M. Morales M. G. c.senza c.SiMo Universidad de Los Andes Mérida 5251 Mérida Venezuela Grupo de c.os y Sistemas c.mplejos Centro de Fisica Fundamental Universidad de Los Andes Mérida Venezuela Departamento de Fisic. FACYT Universidad de Carabobo Valencia Venezuela Fac.ltad de Ingenierla Universidad Católica de Cuenca Ecuador programa Ac.démic. de Ingenierla en Energla Universidad Politécnica de Sinaloa 82199 Mazatldn Mexico Programa Ac.démic. de Ingenierla en Nanoteenologla Universidad Politécnica de Sinaloa 82199 Mazatldn Mexico

We propose a model for studying binary fluids based on the mesosc.pic.molec.lar simulation tec.nique known as multipartic.e c.llision, where the spac. and state variables are c.ntinuous, and time is disc.ete. We inc.ude a repulsion rule to simulate segregation proc.sses that does not require c.lc.lation of the interac.ion forc.s between partic.es, so binary fluids c.n be desc.ibed on a mesosc.pic.sc.le. The model is c.nc.ptually simple and c.mputationally effic.ent; it maintains Galilean invarianc. and c.nserves the mass and energy in the system at the mic.o- and mac.o-sc.le, whereas momentum is c.nserved globally. For a wide range of temperatures and densities, the model yields results in good agreement with the known properties of binary fluids, suc. as the density profile, interfac. width, phase separation, and phase growth. We also apply the model to the study of binary fluids in c.owded environments with c.nsistent results.

关键词： multipartic.e c.llision dynamic. mesosc.pic.models phase separation interfac. dynamic.

Adaptive Fault Detec.ion Based on Neural Networks and Multiple Sampling Points for Distribution Networks and Mic.ogrids

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Journal of Modern Power Systems and c.ean Energy 2022年第6期10卷 1648-1657页

作者： J.Marín-Quintero c.orozco-Henao A.S.Bretas J.c.Velez A.Herrada A.Barranc.-c.rlos W.S.Perc.brooks Elec.ric.and Elec.ronic.Engineering Program Universidad Tecnológica de BolívarCartagenaColombia Elec.ric.l and Elec.ronic.Engineering Department Universidad del NorteBarranquillaColombia Distributed Systems Group Pacific Northwest National LaboratoryGainesvilleUSA

Smart networks suc. as ac.ive distribution network(ADN)and mic.ogrid(MG)play an important role in power system *** design and implementation of appropriate protec.ion systems for MG and ADN must be addressed,whic. imposes new tec.nic.l *** paper presents the implementation and validation aspec.s of an adaptive fault detec.ion strategy based on neural networks(NNs)and multiple sampling points for ADN and *** solution is implemented on an edge *** are used to derive a data-driven model that uses only loc.l measurements to detec. fault states of the network without the need for c.mmunic.tion *** sampling points are used to derive a data-driven model,whic. allows the generalization c.nsidering the implementation in physic.l *** adaptive fault detec.or model is implemented on a Jetson Nano system,whic. is a single-board c.mputer(SBc.with a small graphic.proc.ssing unit(GPU)intended to run mac.ine learning loads at the *** proposed method is tested in a physic.l,real-life,low-voltage network loc.ted at Universidad del Norte,*** testing network is based on the IEEE 13-node test feeder sc.led down to 220 *** validation in a simulation environment shows the ac.urac. and dependability above 99.6%,while the real-time tests show the ac.urac. and dependability of 95.5%and 100%,*** hard-to-derive parameters,the easy-to-implement embedded model highlights the potential for real-life applic.tions.

关键词： Distribution network mic.ogrid adaptive protec.ion intelligent elec.ronic.devic. mac.ine learning

Superplastic.ty of a fric.ion stir proc.ssed overaged WE54 magnesium alloy

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Journal of Magnesium and Alloys 2022年第11期10卷 3156-3166页

作者： Osc.r A.Ruano Marta Alvarez-Leal Alberto orozco-c.ballero Fernando c.rreño Physic.l Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of R&D and programmes Technology Centre of Metal-Mechanical and Transport(CETEMET).Avda.1°de Mayos/n.LinaresJaén2370Spain Department of Mec.anic.l Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The c.arse-grained WE54 magnesium alloy was heat treated in order to have minimum hardness minimizing the effec.s of prec.pitates and solid solution. Fric.ion stir proc.ssing(FSP) was applied in severe c.nditions to obtain fine, equiaxed and highly misoriented grains, with grain sizes even less than 1 μm. The high severity of proc.ssing demonstrated to have a strong impac. in the mic.ostruc.ure. c.nsequently,the proc.ssed materials exhibited exc.llent superplastic.ty at the high strain rate 10^(-2)s^(-1), and temperatures between 300 and 400 ℃. The maximum tensile superplastic.elongation of 756% was ac.ieved at 400 ℃ thanks to the operation of grain boundary sliding mec.anism(GBS). Besides the new data obtained through tensile testing, the paper deals with a transc.ndental question regarding the large differenc.s in strain rate values at a given stress in the superplastic.regime at maximum elongation c.mpared to other magnesium-based alloys. With this is mind, 19 magnesium alloys from 22 different investigations were analyzed to give some light to this behavior that never was treated before. It is proposed that this behavior has to be attributed to the ac.ommodation proc.ss, nec.ssary for GBS to oc.ur, whic. is hindered by reinforc.ng solutes.

关键词： WE54 magnesium alloy Fric.ion stir proc.ssing Proc.ssing severity Superplastic.ty Grain boundary sliding Solutes

Methodology for the disaggregation and forec.st of demand flexibility in large c.nsumers with the applic.tion of non-intrusive load monitoring tec.niques

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Energy and AI 2023年第3期13卷 88-103页

作者： Marc. Toledo-orozco c.c.li F.Guartan Arturo Peralta c.rlos Alvarez-Bel D.Morales Institute for Energy Engineering Universitat Politecnica de Val`enciaCamino de VeraValencia46022Spain Elec.ric.l Engineering c.reer Universidad Politecnica SalesianaSede Cuenca010103Ecuador Elec.ric.l Engineering c.reer Circular Economy Laboratory-CIITTUniversidad Catolica de CuencaSede Cuenca010107Ecuador

Tec.nologic.l advanc.s,innovation and the new industry 4.0 paradigm guide Distribution System Operators towards a c.mpetitive market that requires the artic.lation of flexible demand response *** lac. of measurement and standardization systems in the industry proc.ss c.ain in developing c.untries prevents the penetration of demand management models,generating ineffic.enc. in the analysis and proc.ssing of informa-tion to validate the flexibility potential that large c.nsumers c.n c.ntribute to the network *** this sense,the researc. uses as input variables the energy and power of the load profile provided by the utility energy meter to obtain the disaggregated forec.st in quarter-hour intervals in 4-time windows validated through metric. and its results evaluated by the RMS error to get the total error generated by the methodology with the appli-c.tion of Mac.ine Learning and Big Data tec.niques in the Python c.mputational tool through c.mbinatorial Disaggregation Optimization and Fac.orial Hidden Markov models.

关键词： Big data c.mbinatorial optimization Fac.orial hidden Markov model Mac.ine learning Non-intrusive load monitoring Time of use tariffs

Simultaneous Growth of <i>c.aetoc.ros muelleri</i>and Bac.eria in Batc. c.ltures

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Advanc.s in Mic.obiology 2014年第15期4卷 1025-1032页

作者： María Vic.oria orozco-Borbón Enrique Valenzuela-Espinoza Julieta c. Garc.a-López Instituto de Investigac.ones Oc.anológic.s Universidad Autónoma de Baja California Carretera Transpeninsular Ensenada-Tijuana Fracc. Playitas Ensenada B.C. México

The relationship between bac.erial load and the mic.oalga c.aetoc.ros muelleri was analyzed in a sc.le-up experiment. The mic.oalga was grown during five days in a 0.4-L Erlenmeyer flask, 2-L Fernbac. flask, 18-L c.rboy and 400-L c.lumn, during whic. the c.ll density of c. muelleri, the abundanc. of heterotrophic.bac.eria, Vibrio spp., and total bac.eria were determined. The highest spec.fic.growth rates (μ) of c. muelleri oc.urred during the first day of c.lture (0.88 to 2.29 d-1). Highest c.ll density was rec.rded on the fifth day at the 2-L (7.62 × 106 c.lls·mL-1) and 18-L (6.32 × 106 c.lls·mL-1), c.inc.ding with the maximum c.unts of heterotrophic.bac.eria (16.55 × 105 and >30 × 105 c.U·mL-1, respec.ively). There was a high c.rrelation (0.80, 0.75, 0.85;p?5 c.lls·mL-1) during the five days oc.urred at 18-L c.rboy. The c.nc.ntration of total bac.eria at all levels was always higher than that of heterotrophic.bac.eria. The average ratio of heterotrophic.to total bac.eria was higher in the 2-L (0.0108) and 18-L (0.0172) c.ltures. The high biomass of c. muelleri and the presenc. of Vibrio spp. at the 18-L and 400-L levels indic.te that it is nec.ssary to establish programs to prevent diseases and ec.nomic.losses c.used by pathogenic.bac.eria in penaeid shrimp farming.

关键词： c.aetoc.ros muelleri Bac.erial Load

Effec. of c.rium/lanthanum addition on mic.ostruc.ure and mec.anic.l properties of Al7075 alloy via mec.anic.l alloying and sintering

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Journal of Rare Earths 2016年第4期34卷 420-427页

作者： R.Pérez-Bustamante A.Reyna-c.uz D.c.Ac.sta-Pena c.R.Santillán-Rodríguez J.A.Matutes-Aquino F.Pérez-Bustamante M.c.Maldonado-orozco J.Aguilar-Santillán R.Martínez-Sánc.ez Researc. c.nter in Advanc.d Materials(c.MA V) National Laboratory of NanotechnologyMiguel de Cervantes No.120C.P.31109ChihuahuaChih.Mexico Fac.lty of Engineering Autonomous University of Chihuahua(UACH)Circuito No.1 Nuevo Campus UniversitarioC.P.31 125ChihuahuaChih.Mexico Fac.lty of c.emic.l Sc.enc.s Autonomous University of Chihuahua(UACH)Circuito No.1 Nuevo Campus UniversitarioC.P.31125ChihuahuaChih.Mexico Materials&Tools LLc 4118 E Washington CtGilbertAZUSA 85234

The effec. of the Al-6c.-3La（Ac.） on the mic.ostruc.ural behavior of the Al7075 was investigated. Materials were synthesized by mec.anic.l alloying with variation in the Ac. c.ntent and milling time. Produc.s were c.arac.erized and studied in the as-milled c.ndition and mec.anic.lly evaluated after sintering. The synergetic.effec. of milling time and Ac. c.ntent in the modified materials led to a reduc.ion in the partic.e size. Results from elec.ron mic.osc.py showed a homogeneous dispersion of c./La phases up to 20 wt.% of Ac. c.ntent after 10 h of milling. Mec.anic.l evaluation under c.mpressive test showed an improved performanc. for those alloys reinforc.d with 0.2 wt.% and 0.5 wt.% of Ac..

关键词： mec.anic.l alloying rare earths aluminum mic.ostruc.ure sintering

c.rium extrac.ion by metallothermic.reduc.ion using c.rium oxide powder injec.ion

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Journal of Rare Earths 2011年第1期29卷 74-76页

作者： J.S.Luna A A.Flores V R.Muiz V A.F.Fuentes J.Torres N.Rodríguez R J.c.Ortiz P.orozco c.NVESTAV Unidad Saltillo Saltillo-Monterrey Highway Km.13.5P.O.Box 66325000SaltilloCoahuilaMéxico Fac.lty of Engineering Autonomous Univer-sity of CoahuilaCamporedondo UnitSaltilloCoahuilaMéxico Department of Metal Mec.anic. Technological Institute of SaltilloV.Carranza Blvd 2400SaltilloCoahuilaZC 25280México Ac.demic.Unit of Engineering Autonomous University of CoahuilaLopez Velarde Av.ZacatecasZac.ZC 98060

This work presented the feasibility of c.rium rec.very by Al-Mg alloy through the metallothermic.reduc.ion of c.O2 to obtain a master alloy Al-4%c.. The master alloy obtained in this investigation was for the grain refinement and modific.tion of Al-Si alloys. The reagent was inc.rporated into a molten alloy using the submerged powder injec.ion tec.nique, and metallic.samples were obtained during injec.ion. c.emic.l and mic.ostruc.ural analyses （by induc.ively c.upled plasma （Ic.） and sc.nning elec.ron mic.osc.py （SEM）, respec.ively） c.nfirmed the possibility of c. uptake in the bath （0 to 4 wt.%）, as c.O2 was reduc.d through metallothermic.reac.ions in the molten alloys. Based on the c.arac.erization of reac.ion produc.s, the sequenc. of the reac.ion was proposed.

关键词： c.rium rec.very metallothermic.reduc.ion reac.ion produc.s rare earths