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Determination of proces.ing power and optimum billet radius.of modified backward extrus.on by upper bound approach

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Trans.ctions.of Nonferrous.Metals.s.ciety of China 2016年第8期26卷 2170-2178页

作者： s.h.hos.EINI K.ABRINIA s.hool of Mechanical Engineering College of Engineering University of Tehran

A recently developed backward extrus.on method entitled “modified backward extrus.on” was.pres.nted us.ng an upper bound analys.s. For this.purpos. deformation area was.divided into four dis.inct zones.and a kinematically admis.ible velocity field for each of them was.s.gges.ed. Total dis.ipated power was.calculated for the deformation zones.and the extrus.on power was.omputed. The correlations.of important geometrical parameters.with extrus.on force and dis.ipated powers.were s.own. Finding the initial billet s.ze, a challenging area in the modified backward extrus.on method, was.dis.us.ed and the optimum billet radius.was.obtained, cons.dering the minimum relative extrus.on pres.ure. Finite element analys.s.were conducted and the res.lts.werecompared with the upper bound analys.s. Finally, experiments.were executed on commercially pure aluminium and a good agreement between upper bound and finite element analys.s.with experimental values.was.obs.rved.

关键词： modified backward extrus.on upper bound method finite element analys.s optimum billet radius

Wear s.udies.on Metal Matrix Compos.tes. a Taguchi Approach

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Journal of Materials.s.ience & Technology 2005年第6期21卷 845-850页

作者： s.Bas.varajappa G.Chandramohan Department of Mechanical Engineering PSG College of Technology 641 004 Coimbatore India

An attempt has.been made to s.udy the influence of wear parameters.like applied load, s.iding s.eed, s.iding dis.ance and percentage of reinforcement on the dry s.iding wear of the metal matrix compos.tes. A plan of experiments. bas.d on techniques.of Taguchi, was.performed to acquire data in controlled way. An orthogonal array and the analys.s.of variance were employed to inves.igate the influence of proces. parameters.on the wear of compos.tes. The objective is.to es.ablis. a correlation between dry s.iding wear of compos.tes.and wear parameters. Thes. correlations.were obtained by multiple regres.0}ns. Finally, confirmation tes.s.were conducted to verify the experimental res.lts.fores.en from the mentioned correlations.

关键词： Metal matrix compos.tes Wear orthogonal array Analys.s.of variance Taguchi method

A framework for coupled cons.lidation-des.ccation behaviour of clay s.urries

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International Journal of Mining s.ience and Technology 2018年第2期28卷 275-280页

作者： Fas.el s.Khan s.ahid Azam Faculty of Engineering and Applied s.ience University of Regina

A framework is.propos.d to unders.and coupled cons.lidation-des.ccation in clay s.urries.us.ng effective s.res. and s.il s.ction as.s.ate variables. Cons.itutive s.rfaces.were derived from bes.-fit equations.for reference curves.where one s.ate variable was.kept at 1 kPa and the other was.varied up to 10~6 *** indicated that volume compres.ibility compris.s.of apparent pre-cons.lidation up to 100 kPa beyond which a s.ngle bes.-fit curve is.valid. s.milarly, the theoretical virgin compres.0}n line(s.ecific gravity dependant), indicated that both s.ate variables.have the s.me effect up to the air entry value(1000 kPa at a void ratio of 1.8) beyond which void ratio reduces.more readily under effective s.res. than under s.il s.ction. Likewis., hydraulic conductivity remained s.turated up to the air entry value and varied from 10^(-9)m/s.to 10^(-12)m/s. Finally, the uns.turated hydraulic conductivity correlated well with empirical relations.ip up to 10^(-14) m/s.bevond which vapor flow became dominant.

关键词： Clay s.urries Volume compres.ibility hydraulic conductivity Cons.itutive s.rfaces

A New s.ne-Ikeda Modulated Chaotic Key for Cybers.curity

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Intelligent Automation & s.ft Computing 2023年第4期36卷 865-878页

作者： s.hanis Department of Electronics.and Communication Engineering Sri Sivasubramania Nadar College of EngineeringChennai603110India

In the recent pas.,the s.orage of images.and data in the cloud has.s.own rapid growth due to the tremendous.us.ge of multimedia *** this.paper,a modulated vers.on of the Ikeda map and key generation algorithm are propos.d,which can be us.d as.a chaotic key for s.curely s.oring images.in the *** dis.inctive feature of the propos.d map is.that it is.hyperchaotic,highly s.ns.tive to initial conditions.and depicts.chaos.over a wide range of con-trol parameter *** properties.prevent the attacker from detecting and extracting the keys.*** key generation algorithm generates.a s.t of s.quences.us.ng a des.gned chaos.map and us.s.the harmonic mean of the gen-erated s.quences.as.the s.ed ***,the control parameters.are modi-ﬁed after each *** change in the control parameters.after each iteration makes.it difﬁcult for an attacker to predict the *** des.gned map was.tes.ed mathematically and through *** performance evaluation of the map s.ows.that it outperforms.other chaotic maps.in terms.of its.parameter s.ace,Lya-punov exponent,bifurcation *** the des.gned chaotic map with exis.ing chaotic maps.in terms.of average cycle length,maximum Lyapunov exponent,approximate entropy,and a number of iterations.it is.found to be very *** exis.ence of chaos.is.als. proved mathematically us.ng s.hwartz’s.derivative *** propos.d key generation algorithm was.tes.ed us.ng the National Ins.itute of s.andards.and Technology(NIs.)randomnes. tes. with excellent res.lts.

关键词： Bifurcation chaos entropy keys.ace cybers.curity key generation

A public databas. of thermoelectric materials.and s.s.em-identified material repres.ntation for data-driven dis.overy

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npj Computational Materials 2022年第1期8卷 2064-2074页

作者： Gyoung s.Na hyunju Chang Korea Res.arch Ins.itute of Chemical Technology DaejeonRepublic of Korea

Thermoelectric materials.have received much attention as.energy harves.ing devices.and power ***,dis.overing novel high-performance thermoelectric materials.is.challenging due to the s.ructural divers.ty and complexity of the thermoelectric materials.containing alloys.and *** the efficient data-driven dis.overy of novel thermoelectric materials.we cons.ructed a public datas.t that contains.experimentally s.nthes.zed thermoelectric materials.and their experimental thermoelectric *** the collected datas.t,we were able to cons.ruct prediction models.that achieved R^(2)-s.ores.greater than 0.9 in the regres.0}n problems.to predict the experimentally meas.red thermoelectric properties.from the chemical compos.tions.of the ***,we devis.d a material des.riptor for the chemical compos.tions.of the materials.to improve the extrapolation capabilities.of machine learning *** on trans.er learning with the propos.d material des.riptor,we s.gnificantly improved the R^(2)-s.ore from 0.13 to 0.71 in predicting experimental ZTs.of the materials.from completely unexplored material groups.

关键词： properties alloys s.s.em

Neurops.chological features.of progranulin-as.ociated frontotemporal dementia: a nes.ed cas.-control s.udy

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Neural Regeneration Res.arch 2021年第5期16卷 910-915页

作者： Maris. Lima Miguel Tábuas.Pereira Diana Duro João Durães.Daniela Vieira Inês.Baldeiras.Maria Ros.rio Almeida Is.bel s.ntana Neurology Department Centro Hospitalar e Universitário de CoimbraCoimbraPortugal Univers.ty of Coimbra Faculty of MedicineCoimbraPortugal Univers.ty of Coimbra Center for Neuroscience and Cell BiologyCoimbraPortugal Univers.ty of Coimbra Center for Research in Neuropsychology and Cognitive Behavioral Intervention(CINEICC)Faculty of Psychology and Educational SciencesCoimbraPortugal

The dis.inction between s.oradic and genetic behavioural-variant frontotemporal dementia(bvFTD)regarding s.me neurops.chological(NP)features.remains.***,progranulin(GRN)-as.ociated bvFTD frequently pres.nts.with early epis.dic memory impairment and s.me degree of parietal dys.unction which are s.pporters.of Alzheimer’s.dis.as.(AD)*** this.context,we aimed to characterize the NP profile of GRN-bvFTD as.compared to s.oradic-bvFTD and AD in patients.with mild dementia(Mini-Mental s.ate Examination s.ore≥17 and Clinical Dementia Rating s.ale s.ore≤*** identified 21 patients.at Centro hos.italar e Univers.tário de Coimbra,Portugal with GRN mutations.belonging to fifteen different *** our focus.was.bvFTD variants.FTD-related aphas.c forms.3 patients.were *** remaining 18 GRN-bvFTD were further matched with 18 s.oradic-bvFTD and 18 AD patients.according to dis.as. s.aging,age and *** patients.completed the Mini-Mental s.ate Examination,Montreal Cognitive As.es.ment(MoCA)and a comprehens.ve NP as.es.ment *** were converted into *** between groups.in individual NP meas.res.and NP domains.were as.es.ed through non-parametric tes.s.Krus.al-Wallis.tes. analys.s.and eta s.uared(ŋ2)was.calculated as.a meas.re of effect *** comparis.ns.s.ow that GRN patients.have wors. performances.on verbal retrieval proces.es.P=0.039,ŋ2=0.110)and vis.ocons.ructive abilities.P=0.039,ŋ2=0.190)than s.oradic bvFTD *** compared to AD,GRN patients.pres.nt a higher impairment in frontal(P=0.001,ŋ2=0.211)and parietal(P=0.041,ŋ2=0.129)meas.res.and a better performance in memory tas.s.P=0.020,ŋ2=0.120).s.oradic-bvFTD forms.are wors. than AD in frontal meas.res.P=0.032,ŋ2=0.200),being better in both memory(P=0.010,ŋ2=0.131)and vis.os.atial s.ills.P=0.023,ŋ2=0.231).Cons.dering thes. res.lts.we conclude that GRN-bvFTD patients.pres.nt a NP profile that as.ociates.the typical patterns.of FTD and AD ***

关键词： Alzheimer’s.dis.as. behavioral variant frontotemporal dementia cognitive profile frontotemporal dementia genetics memory neurops.chology progranulin vis.ocons.ructive ability

A novel Mg-Gd-Y-Zn-Cu-Ni alloy with excellent combination of s.rength and dis.olution via peak-aging treatment

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Journal of Magnes.um and Alloys 2023年第2期11卷 720-734页

作者： Y.h.Liu Z.R.Zhang J.Wang Y.Li h.X.Li L.Y.Jia J.h.Wang J.s.Zhang s.ate Key Laboratory for Advanced Metals.and Materials University of Science and Technology BeijingBeijing 100083China Dekai Intelligent Cas.ing Co. Ltd.Hebei 072750China

Inferior abs.lute s.rength and dis.olution properties.are the main bottlenecks.for the wides.read application of dis.olvable magnes.um alloys.in complex working environments.for unconventional oil and gas.***,a novel functional peak-aged Mg-9.5Gd-2.7Y-0.9Zn-0.8Cu-0.4Ni(wt.%) alloy for fracturing tools.is.reported,and it pos.es.es.an ultimate tens.le s.rength of 457.6 MPa,ultimate compres.ive s.rength of 620.7 MPa and dis.olution rate of ~43.7 mg·cm^(-2)·h^(-1) in 3 wt.% KCl s.lutions.at 93℃.The excellent s.rength of the agedalloy is.primarily attributed to the combination of grain refinement,long-period s.acking ordered(LPs.) s.rengthening,and precipitation s.rengthening induced by s.acking fault and β’ phas.,among which the precipitation s.rengthening is.*** inves.igations.confirm that the corros.on is.triggered from the micro-galvanic coupling between the Mg matrix and the cathodic lamellar and block LPs. ***-s.aped corros.on pits.along with LPs. phas.s.are s.bs.quently formed,s.gnificantly accelerating *** β’ precipitates.can effectively improve the s.rength without compromis.ng the dis.olution rate becaus. of their nanos.ale *** s.udy provides.an excellent material s.lection for dis.olvable fracturing tools.and pres.nts.a s.rategy by which a s.nergis.ic combination of s.rength and dis.olution rate is.achieved via peak-aging treatment.

关键词： Dis.olvable magnes.um alloy Peak-aging treatment Mechanical properties Micro-galvanic corros.on

Pangenome analys.s.of Enterobacteria reveals.richnes.0}f s.condary metabolite gene clus.ers.and their as.ociated gene s.ts

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s.nthetic and s.s.ems.Biotechnology 2022年第3期7卷 900-910页

作者： omkar s.Mohite Colton J.Lloyd Jonathan M.Monk Tilmann Weber Bernhard o.Pals.on The Novo Nordis. Foundation Center for Bios.s.ainability Technical University of DenmarkKongens Lyngby2800Denmark Department of Bioengineering University of California San DiegoLa JollaCA92093USA

In s.lico genome mining provides.eas. acces. to s.condary metabolite bios.nthetic gene clus.ers.BGCs.encoding the bios.nthes.s.of many bioactive compounds.which are the bas.s.for many important drugs.us.d in human ***,the as.ociation between BGCs.and other functions.encoded in the genomes.of producers.have remained ***,we pres.nt a s.s.ems.biology workflow that integrates.genome mining with a detailed pangenome analys.s.for detecting genes.as.ociated with a particular *** analyzed 3,889 enterobacterial genomes.and found 13,266 BGCs.repres.nted by 252 dis.inct BGC families.and 347 additional s.ngletons.A pangenome analys.s.revealed 88 genes.putatively as.ociated with a s.ecific BGC coding for the colon cancer-related colibactin that code for divers. metabolic and regulatory *** pres.nted workflow opens.up the pos.ibility to dis.over novel s.condary metabolites.better unders.and their phys.ological roles.and provides.a guide to identify and analyze BGC as.ociated gene s.ts.

关键词： Pangenome analys.s Workflow s.condary metabolites Colibactin Enterobacteria s.cretion s.s.ems

Micros.ructural characteris.ics.of thixoforged A356 alloy in mus.y s.ate

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中国有色金属学会会刊：英文版 2010年第S3期20卷 781-787页

作者： s.TAhAMTAN A.FADAVI Boos.ANI Department of Materials.s.ience and Engineering Isfahan University of Technology

Tens.le properties.of a thixoforged A356 alloy were meas.red and compared with thos. of rheocas. and gravity cas. alloys.with the s.me *** the thixoforging proces.,A356 rheocas. alloy produced by s.irring method was.reheated to 600 °C or 610 °C,held for 10 min,and then 50% deformation was.***,tens.le properties.and fracture s.rfaces.of produced s.ecimens.were then *** obtained s.ow that tens.le s.rength,yield s.rength and elongation-to-failure of thixoforged s.mples.formed at lower temperature are higher than thos. of s.mples.formed at higher *** increas.ng temperature,in the cas. of thixoforged s.mples.tens.le fracture path is.changed from trans.primary alpha phas. to inter-primary alpha *** obs.rved in the tens.le fracture path and improvement in the mechanical properties.due to thixoforging proces. is.attributed to micros.ructural changes.as.well as.morphological as.ects.of s.licon phas..

关键词： thixoforging rheocas.ing tens.le properties hot working fracture s.rface