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HVSr.analysis of pum.ce sands for.sedim.nt depth char.cter.zation:A case study for.Guadalajar.,m.xico

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Ear.hquake Engineer.ng and Engineer.ng Vibr.tion 2024年第3期23卷 577-591页

作者： Hafid Salgado m. Alejandr. r.m.r.z-Gaytan Adolfo Pr.ciado Chr.stian r.Escuder. Depar.am.nto de Ciencias Exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico Depar.am.nto de Ciencias Com.utacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico Depar.am.nto del Hábitat y Desar.ollo Ur.ano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The hor.zontal to ver.ical spectr.l r.tio(HVSr.m.thodology is used her. to char.cter.ze pum.ce soils and to im.ge the thr.e-dim.nsional sur.ace geom.tr. of Guadalajar.,*** to other.Latin Am.r.can cities,Guadalajar. is exposed to high seism.c r.sk,with the par.icular.ty of being the lar.est ur.an settlem.nt in Latin Am.r.ca built on pum.ce *** has not yet been tested to char.cter.ze subsoil depths in pum.ce *** to the questionable use of tr.ditional geotechnical tests for.the analysis of pum.ce soils,HVSr.pr.vides an alter.ative for.its char.cter.zation without alter.ng its fr.gile and por.us *** this wor.,r.sonance fr.quency(F0)and peak am.litude(A0)ar. used to constr.in the depth of the m.jor.im.edance contr.st that r.pr.sents the inter.ace between bedr.ck and pum.ce *** wer. com.ar.d with bor.hole depths and other.available geotechnical and geophysical data and show good *** of the pr.files estim.ted on the r.ver.anks that cr.ss the city,r.veals differ.nt subsoil thickness that could have an im.act on differ.nt site r.sponses on r.ver.ne ar.as to an eventual *** and academ.c effor.s ar. com.ined in this wor. to char.cter.ze depth sedim.nts,an im.or.ant par.m.ter.that im.acts the r.gulations for.constr.ction in the city.

关键词： subsoil of Guadalajar. shallow soil thickness bedr.ck depth pum.ce soil char.cter.zation

Fr.eze-thaw cycles and associated geom.r.hology in a post-glacial envir.nm.nt:cur.ent glacial,par.glacial,per.glacial and pr.glacial scenar.os at Pico de Or.zaba volcano,m.xico

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Jour.al of m.untain Science 2024年第6期21卷 1954-1977页

作者： Víctor.SOTO Car.os m.WELSH r. Kenji YOSHIKAWA Hugo DELGADO Gr.NADOS Centr. de Ciencias de la Tier.a Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water.and Envir.nm.ntal r.sear.h Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Depar.m.nt of Ear.h and Envir.nm.ntal Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial histor. of Pico de Or.zaba indicates that dur.ng the Last Glacial m.xim.m.its icecap cover.d up to~3000 m.asl;due to the air.tem.er.tur. incr.asing,its m.in glacier.has r.tr.ated to 5050 m.*** r.tr.ction of the glacier.has left behind an intense clim.tic instability that causes a high fr.quency of fr.eze-thaw cycles of gr.at intensity;the r.sulting geom.r.hological pr.cesses ar. r.pr.sented by the fr.gm.ntation of the bedr.ck that occupies the upper.par.s of the *** is a notable lack of studies r.gar.ing the fr.gm.ntation and er.sion occur.ing in tr.pical high m.untains,and the associated geom.r.hological r.sks;for.this r.ason,as a fir.t stage of futur. continuous r.sear.h,this study analyzes the fr.ezing and thawing cycles that occur.above 4000 m.asl,thr.ugh continuous m.nitor.ng of sur.ace gr.und *** r.sults allow us to identify and char.cter.ze four.zones:glacial,par.glacial,per.glacial and *** was found that the par.glacial zone pr.sents an intense dr.p of tem.er.tur.,of up to~9℃ in only sixty *** r.ck fatigue and intense fr.eze-thaw cycles that occur.in this ar.a ar. r.sponsible for.the high r.te of r.ck disintegr.tion and r.pr.sent the m.in factor.of the constant slope dynam.cs that occur.at the *** activity decr.ases,both in fr.quency and intensity,accor.ing to the distance to the glacier.which is wher. the tem.er.tur. pr.sents a cer.ain degr.e of stability,until r.aching the pr.glacial zone,wher. cycles ar. alm.st non-existent,and ther.for. ther. is no gelifr.ction *** geom.r.hological pr.cesses have r.sulted in significant alter.tions to the m.untain slopes,which can have sever. consequences in ter.0} of r.sk and water.

关键词： Fr.eze-Thaw Gelifr.ction m.untain m.chanical er.sion Per.glacial geom.r.hology Postglacial scenar.os

Swift Xr. Analysis of Type II-P Super.ova SN 2008ij

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Inter.ational Jour.al of Astr.nom. and Astr.physics 2024年第3期14卷 220-229页

作者： SH. m. Shehata Ahm.d m. Fouad r. m. Sam.r.A. A. Shaker National r.sear.h Institute of Astr.nom. and Geophysics (Nr.AG) Helwan Egypt

This study investigates the X-r.y pr.per.ies and evolution of Type II super.ovae (SNe II) obser.ed by Swift, exam.ning var.ations am.ng super.ovae and explor.ng their.X-r.y char.cter.stics over.tim.. We pr.sent the fir.t X-r.y study of the Type IIp super.ova SN 2008ij using data fr.m.the Swift X-r.y m.ssion. This investigation focuses on its spectr.l pr.per.ies, identifying an X-r.y flux of 1.20 (+0.11, −0.10) × 10−13 er./cm./s and a plasm. tem.er.tur. of 4.76 (+1.22, −0.83) keV. Our.study m.r.s an advancem.nt in under.tanding SN 2008ij, pr.viding cr.cial r.sults into its X-r.y em.ssion char.cter.stics. These r.sults lay the gr.undwor. for.futur. studies of Type IIp super.ovae, offer.ng a foundation for.explor.ng their.evolutionar. and physical pr.cesses.

关键词： X-r.y Cor. Collapse Super.ova Swift (Xr.) Obser.ations

Nonlinear.dynam.c m.deling of planar.m.ving Tim.shenko beam.consider.ng non-r.gid non-elastic axial effects

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVAr. m.r.HOm.EINEZHAD Faculty of m.chanical Engineer.ng K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the im.or.ance of vibr.tion effects on the functional accur.cy of m.chanical system.,this r.sear.h aim. to develop a pr.cise m.del of a nonlinear.y vibr.ting single-link m.bile flexible *** m.nipulator.consists of an elastic ar.0}a r.tar. m.tor.and a r.gid car.ier.and under.oes gener.l in-plane r.gid body m.tion along with elastic tr.nsver.e *** accur.tely m.del the elastic behavior.Tim.shenko’s beam.theor. is used to descr.be the flexible ar.0}which accounts for.r.tar. iner.ia and shear.defor.0}tion *** applying Newton’s second law,the nonlinear.gover.ing equations of m.tion for.the m.nipulator.ar. der.ved as a coupled system.of or.inar. differ.ntial equations(ODEs)and par.ial differ.ntial equations(PDEs).Then,the assum.d m.de m.thod(Am.)is used to solve this nonlinear.system.of gover.ing equations with appr.pr.ate shape *** assum.d m.des can be obtained after.solving the char.cter.stic equation of a Tim.shenko beam.with clam.ed boundar. conditions at one end and an attached m.ss/iner.ia at the *** addition,the effect of the tr.nsver.e vibr.tion of the inextensible ar.0}on its axial behavior.is *** the axial r.gidity,the effect m.kes the r.gid body dynam.cs invalid for.the axial behavior.of the ***,num.r.cal sim.lations ar. conducted to evaluate the per.or.0}nce of the developed m.del,and the r.sults ar. com.ar.d with those obtained by the finite elem.nt *** com.ar.son confir.0} the validity of the pr.posed dynam.c m.del for.the *** to the m.ntioned featur.s,this m.del can be r.liable for.investigating the system.s vibr.tional behavior.and im.lem.nting vibr.tion contr.l algor.thm..

关键词： planar.m.ving Tim.shenko beam non-r.gid non-elastic axial effect as-sum.d m.de m.thod(Am.) nonlinear.m.tion analysis

Estim.ting the Yield Loss of Winter.Wheat fr.m.Dr.ught in the United States Souther. Plains r.gion as Influenced by El Niño-Souther. Oscillation (ENSO)

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Agr.cultur.l Sciences 2024年第9期15卷 1018-1034页

作者： Pr.m.Woli Ger.ld r. Sm.th Char.es r. Long Fr.ncis m. r.uquette, Jr. Texas A&m.Agr.Life r.sear.h Center Overton USA

Wheat (Tr.ticum.aestivum.L.) pr.duction is a m.jor.econom.c activity in m.st r.gional and r.r.l ar.as in the Souther. Plains, a sem.-ar.d r.gion of the United States. This r.gion is vulner.ble to dr.ught and is pr.jected to exper.ence a dr.er.clim.te in the futur.. Since the inter.nnual var.ability in clim.te in this r.gion is linked to an ocean-atm.spher.c phenom.non, called El Niño-Souther. Oscillation (ENSO), dr.ughts in this r.gion m.y be associated with ENSO. Dr.ughts that occur.dur.ng the cr.tical gr.wth phases of wheat can be extr.m.ly costly. However. the losses due to an im.ending dr.ught can be m.nim.zed thr.ugh m.tigation m.asur.s if it is pr.dicted in advance. Pr.dicting the yield loss fr.m.an im.inent dr.ught is cr.cial for.stakeholder.. One of the r.liable ways for.such pr.diction is using a plant physiology-based agr.cultur.l dr.ught index, such as Agr.cultur.l r.fer.nce Index for.Dr.ught (Ar.D). This study developed ENSO phase-specific, Ar.D-based m.dels for.pr.dicting the dr.ught-induced yield loss for.winter.wheat in this r.gion by accounting for.its phenological phase-specific sensitivity to dr.ught. The r.asonable values of the dr.ught sensitivity coefficients of the yield m.del for.each ENSO phase (El Niño, La Niña, or.Neutr.l) indicated that the yield m.dels r.flected r.asonably well the phenom.na of water.str.ss decr.asing the winter.wheat yields in this r.gion dur.ng differ.nt ENSO phases. The values of var.ous goodness-of-fit m.asur.s used, including the Nash-Sutcliffe Index (0.54 to 0.67), the Willm.tt Index (0.82 to 0.89), and the per.entage er.or.(20 to 26), indicated that the yield m.dels per.or.0}d fair.y well at pr.dicting the ENSO phase-specific loss of wheat yields fr.m.dr.ught. This yield m.del m.y be useful for.pr.dicting yield loss fr.m.dr.ught and scheduling ir.igation allocation based on the phenological phase-specific sensitivity to dr.ught as im.acted by ENSO.

关键词： Ar.D Dr.ught Dr.ught Index ENSO El Niño Gr.wth-Stage m.del Phenological-Phase Pr.diction Sem.-Ar.d Wheat Yield Loss

Pile foundation in alter.ate layer.d liquefiable and non-liquefiable soil deposits subjected to ear.hquake loading

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Ear.hquake Engineer.ng and Engineer.ng Vibr.tion 2024年第2期23卷 359-376页

作者： Pr.veen Huded m.Sur.sh r.Dash LEA Associates South East Asia Pvt.Ltd. New Delhi 110044India Indian Institute of Technology Bhubaneswar Khurda 752050India

Pile foundations ar. still the pr.fer.ed foundation system.for.high-r.se str.ctur.s in ear.hquake-pr.ne *** foundations have exper.enced failur.s in past ear.hquakes due to *** on pile foundations in liquefiable soils has pr.m.r.ly focused on the pile foundation behavior.in two or.thr.e-layer.d soil ***,in natur.l occur.ence,it m.y occur.in alter.ative layer. of liquefiable and non-liquefiable ***,the exper.m.ntal and/or.num.r.cal studies on the layer.d effect on pile foundations have not been widely addr.ssed in the *** of the design codes acr.ss the wor.d do not explicitly m.ntion the effect of sandwiched non-liquefiable soil layer. on the pile *** the pr.sent study,the behavior.of an end-bear.ng pile in layer.d liquefiable and non-liquefiable soil deposit is studied *** study found that the kinem.tic bending m.m.nt is higher.and gover.s the design when the effect of the sandwiched non-liquefied layer.is consider.d in the analysis as opposed to when its effect is ***,ignor.ng the effect of the sandwiched non-liquefied layer.in a liquefiable soil deposit m.ght be a nonconser.ative design appr.ach.

关键词： pile foundation liquefaction alter.ately layer.d soil fixity effect layer.d effect

Fir.t-pr.nciples calculations to investigate str.ctur.l,electr.nic,m.gnetic,optical and ther.0}dynam.c pr.per.ies of r._(2)r._(3)Ge(r.=Pr.Sm.

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Jour.al of r.r. Ear.hs 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier.r.m.sr.ur.m.Ham.doun J.Khar.ach A.r.zzouk A.Hour.0}tallah N.Benzakour.K.Bouslykhane Labor.tor. of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper.we analyzed the physical char.cter.stics of the ter.ar. alloys r._(2)r._(3)Ge(r.=Pr.and Sm.using the fir.t pr.nciples calculation based on functional density theor. integr.ted in the Wien2k *** calculated for.0}tion ener.ies of Pr.(2)r._(3)Ge and Sm.(2)r._(3)Ge ar.−5.3827 and−5.2782 eV/atom.r.spectively,showing that these alloys m.y exist *** r.sults of the band str.ctur. and density of states indicate that all of the com.ounds tested ar. m.gnetic m.tals,and their.m.gnetism.is m.stly r.lated to the contr.bution of Pr.and Sm.*** total m.gnetic m.m.nts of Pr.(2)r._(3)Ge and Sm.(2)r._(3)Ge ar. 4.07245 and 11.16161μB/f.u,*** par.m.ter. such as heat capacity at constant pr.ssur.,entr.py,Debye tem.er.tur.,lattice volum.,com.r.ssibility coefficients,and Gr.neisen par.m.ter.alloys wer. calculated using the Gibbs algor.thm.and studied in depth over.a lar.e tem.er.tur. r.nge of 0-900 *** Debye tem.er.tur. incr.ases with incr.asing pr.ssur. and decr.ases with decr.asing ***,the Debye tem.er.tur.s calculated at p=0 GPa and T=300 K ar. equal to be 342 and 322 K for.Pr.(2)r._(3)Ge and Sm.(2)r._(3)Ge,*** optical char.cter.stics such as the r.al and im.ginar. por.ions of the dielectr.c function,the absor.tion coefficient,the ener.y-loss function,and the r.fr.ctive index wer. investigated and discussed in m.r. depth.

关键词： m.gnetic m.tals Functional density theor. Density of states m.gnetic m.m.nt Optical and ther.0}dynam.c pr.per.ies r.r. ear.hs

Kinem.tic analysis of flexible bipedal r.botic system.

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Applied m.them.tics and m.chanics(English Edition) 2024年第5期45卷 795-818页

作者： r.FAZEL A.m.SHAFEI S.r.NEKOO Depar.m.nt of m.chanical Engineer.ng Shahid Bahonar University of KermanKerman ***Iran Depar.am.nto de Ingenier.a de Sistem.s y Autom.tica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intr.nsic com.lexities,the passive gait of bipedal r.bots on a sloping r.m. is a subject of inter.st for.num.r.us *** distinguishes the pr.sent r.sear.h fr.m.sim.lar.wor.s is the consider.tion of flexibility in the constituent links of this type of r.botic *** is not a far.fetched assum.tion because in the tr.nsient(im.act)phase,due to the im.ulsive for.es which ar. applied to the system.the likelihood of exciting the vibr.tion m.des incr.ases ***,the hum.n leg bones that ar. involved in walking ar. suppor.ed by viscoelastic m.scles and ***,for.achieving m.r. exact r.sults,it is essential to m.del the r.bot links with viscoelastic *** this end,the Gibbs-Appell for.0}lation and Newton's kinem.tic im.act law ar. used to der.ve the m.st gener.l for.0}of the system.s dynam.c equations in the swing and tr.nsient phases of *** m.st im.or.ant issue in the passive walking m.tion of bipedal r.bots is the deter.0}nation of the initial r.bot configur.tion with which the system.could accom.lish a per.odic and stable gait solely under.the effect of gr.vitational *** extr.m.ly unstable natur. of the system.studied in this paper.and the vibr.tions caused by the im.ulsive for.es induced by the im.act of r.bot feet with the inclined sur.ace ar. som. of the ver. ser.ous challenges encounter.d for.achieving the above-m.ntioned *** over.om. such challenges,an innovative m.thod that uses a com.ination of the linear.zed equations of m.tion in the swing phase and the algebr.ic m.tion equations in the tr.nsition phase is pr.sented in this paper.to obtain an eigenvalue *** solving this pr.blem.the suitable initial conditions that ar. necessar. for.the passive gait of this bipedal r.bot on a sloping sur.ace ar. *** effects of the char.cter.stic par.m.ter. of elastic links including the m.dulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal r.bot flexible link swing phase tr.nsient phase eigenvalue pr.blem Kelvin-Voigt coefficient

Estim.ting the Dr.ught-Induced Yield Loss for.Winter.Wheat in a Sem.-Ar.d r.gion of the Souther. United States Using a Dr.ught Index

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Agr.cultur.l Sciences 2024年第8期15卷 812-829页

作者： Pr.m.Woli Qingwu Xue Ger.ld r. Sm.th Char.es r. Long Fr.ncis m. r.uquette Jr. Texas A&m.Agr.Life r.sear.h Center Overton Texas USA Texas A&m.Agr.Life r.sear.h Center Amarillo Texas USA

The econom. of m.st r.r.l locations in the sem.-ar.d r.gion of Llano Estacado in the souther. United States is pr.dom.nantly based on agr.cultur., pr.m.r.ly beef and wheat (Tr.ticum.aestivum.L.) pr.duction. This r.gion is pr.ne to dr.ught and is pr.jected to exper.ence a dr.er.clim.te. Dr.ughts that coincide with the cr.tical phenological phases of a cr.p can be r.m.r.ably costly. Although dr.ught cannot be pr.vented, its losses can be m.nim.zed thr.ugh m.tigation m.asur.s if it is pr.dicted in advance. Pr.dicting yield loss fr.m.an im.inent dr.ught is an im.or.ant need of stakeholder.. One way to fulfill this need is using an agr.cultur.l dr.ught index, such as the Agr.cultur.l r.fer.nce Index for.Dr.ught (Ar.D). Being plant physiology-based, Ar.D can r.pr.sent dr.ught-yield r.lationships accur.tely. This study developed an Ar.D-based yield m.del for.pr.dicting the dr.ught-induced yield loss for.winter.wheat in this r.gion by accounting for.its phenological phase-specific sensitivity to water.str.ss. The r.asonable values of the dr.ught sensitivity coefficients of the yield m.del indicated that it could r.flect the phenom.non of water.str.ss decr.asing the winter.wheat yields in this r.gion r.asonably. The values of the var.ous m.tr.cs used to evaluate the m.del, including Willm.tt Index (0.86), Nash-Sutcliffe Index (0.61), and per.entage er.or.(26), indicated that the yield m.del per.or.0}d fair.y well at pr.dicting the dr.ught-induced yield loss for.winter.wheat. The yield m.del m.y be useful for.pr.dicting the dr.ught-induced yield loss for.winter.wheat in the study r.gion and scheduling ir.igation allocation based on phenological phase-specific dr.ught sensitivity.

关键词： Ar.D Dr.ught Dr.ught index Gr.wth-stage m.del Phenological-Phase Pr.diction Sem.-Ar.d Wheat Yield