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Multiple cycles of ma.netic a.tivity in the Sun a.d Sun-like sta.s a.d their evolution

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Resea.ch in a.tronomy a.d a.trophysics 2018年第7期18卷 21-36页

作者： Elena.a.eksa.drovna.Bruevich Va.ily Vla.imirovich Bruevich Boris Pa.lovich artamonov Lomonosov Moscow Sta.e University Sternberg Astronomical Institute

The wa.elet tra.sform method for high-qua.ity time-frequency a.a.ysis is a.plied to sets of observa.ions of rela.ive sunspot numbers a.d stella. chromosphere fluxes of 10 Sun-like sta.s. Wa.elet a.a.ysis of sola. da.a.shows tha. in a.certa.n interva. of time there a.e severa. cycles of a.tivity with pe- riods of dura.ion which va.y considera.ly from ea.h other： from qua.i-biennia. cycles to lO0-yr cycles. Cyclic a.tivity wa. detected in a.most a.l Sun-like sta.s tha. we exa.ined, even those tha. previously were not considered a. sta.s with cyclic a.tivity a.cording to a.a.ysis using a.Sca.gle periodogra.. The dura.ions of sola. a.d stella. cycles significa.tly cha.ge during the observa.ion period.

关键词： Sun a.tivity - multiple cycles - Sun-like sta.s a.tivity

Deriva.ions of Skew PBW-Extensions

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Communica.ions in Ma.hema.ics a.d Sta.istics 2015年第4期3卷 449-457页

作者： V.a.artamonov Depa.tment of a.gebra Faculty of Mechanics and MathematicsMoscow State UniversityMoscowRussia

The pa.er conta.ns a.cla.sifica.ion of deriva.ions of skew PBW-extensions of rings.

关键词： Deriva.ions Skew polynomia. extensions PBW-extensions

Extended Modules a.d Ore Extensions

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Communica.ions in Ma.hema.ics a.d Sta.istics 2016年第2期4卷 189-202页

作者： Via.heslA. Artamonov Oswa.do Leza.a.Willia. Fa.a.do Moscow Sta.e University MoscowRussia Universida. Na.iona. de Colombia BogotaColombia

In this pa.er,we study extended modules for a.specia. cla.s of Oreextensions.We will a.sume tha. R is a.ring a.d a.will denote the Ore extensiona.=R[X1,...,xn;σ]for whichσis a. a.tomorphism of R,xixj=xjxi a.d xir=σ(r)xi,for every 1a.conditions over the ring R,wewill prove Va.erstein's,Quillen's pa.ching,Horrocks',a.d Quillen-Suslin's theoremsfor this type of non-commuta.ive rings.

关键词： Extended modules a.d rings Quillen-Suslin's methods Ore extensions

Effect of intera.tions of two holes on tensile beha.ior of pa.ch repa.red ca.bon/epoxy woven la.ina.es

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Defence Technology（防务技术） 2023年第3期21卷 88-93页

作者： Gursa.ib Singh Bha.ia.a.ockia.a.a. a. Depa.tment of a.plied Mecha.ics Indian Institute of Technology Madras600036ChennaiIndia

The conventiona. ca.e of pa.ch repa.r involves bonding a.pa.ch over single da.a.e/hole in the la.ina.e.This work investiga.es the effect of intera.tion of two holes on the tensile beha.ior pa.ch repa.red ca.bon epoxy woven la.ina.es.The specimens of[0°/45°/45°/0°]la.ina.es were repa.red with a.hesively bonded two-ply[45°]2externa. pa.ches.Three different ca.es of drilled specimens were produced with different hole a.ra.gements viz.specimens with single centra. hole(SH),with two holes a.igned a.ong the longitudina. a.is(LH)a.d with two holes a.ong tra.sverse a.is(TH).The two-hole specimens were repa.red with two different types,i.***.single la.ge pa.ches(SP)a.d with the two sma.ler pa.ches(DP)of combined bonding a.ea.equa. to the single la.ge pa.ches.Digita. ima.e correla.ion(DIC)wa. employed to ca.ture stra.n contours.The results revea. the difference in the loa. tra.sfer through the pa.ches depending upon the a.ra.gement of holes.The TH repa.red specimen exhibit significa.t loa. recovery(SP-32.75%,DP-34.62%)while the LH specimens result in very ma.gina.(SP-6.11%,DP-4.10%)recovery compa.ed to their drilled ca.e.The TH specimen fa.led by cra.k growing through both the holes benea.h the pa.ch,while the LH specimens fa.led by the fa.lure through only one hole.The use of single la.ge pa.ch over multiple holes a.d multiple sma.l pa.ches individua.ly over ea.h hole ha. no significa.t influence on loa. recovery.

关键词： cra.k pa.ch beha.ior

Improved Lea.-frog Method for Time-doma.n Fa.lt Loca.ion

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JOURNa. OF MODERN POWER SYSTEMS a.D CLEa. ENERGY 2024年第2期12卷 670-674页

作者： Dza.ic, Izudin Ja.r, Ra.ih a. Univ Sa.a.evo Fac Elect Engn Sarajevo 71000 Bosnia & Herceg a.er Univ Beirut Dept Elect & Comp Engn Beirut 11072020 Lebanon

The pa.tia. differentia. equa.ion (PDE) solution of the telegra.her is a.promising fa.lt loca.ion method a.ong time-doma.n a.d model-ba.ed techniques. Recent resea.ch works ha.e shown tha. the lea.-frog process is superior to other explicit methods for the PDE solution. However, its implementa.ion is cha.lenged by determining the initia. conditions in time a.d the bounda.y conditions in spa.e. This letter proposes two implicit solution methods for determining the initia. conditions a.d a. a.a.ytica. wa. to obta.n the bounda.y conditions founded on the signa. decomposition. The results show tha. the proposa. gives fa.lt loca.ion a.cura.y superior to the existing lea.-frog scheme, pa.ticula.ly in the presence of ha.monics.

关键词： Ha.monic a.a.ysis Volta.e Fa.lt loca.ion Time-doma.n a.a.ysis Ma.hema.ica. models Volta.e mea.urement Wa.elet tra.sforms lea.-frog pa.tia. differentia. equa.ion time-doma.n a.a.ysis tra.smission line

Effects of irregula.ity a.d initia. stresses on the dyna.ic response of viscoela.tic ha.f-spa.e due to a.moving loa.

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a.ta.Mecha.ica.Solida.Sinica 2017年第3期30卷 306-317页

作者： a.K. Singh a. Da. a. La.shma. a. Negi a. Cha.topa.hya. Depa.tment of a.plied Ma.hema.ics Indian Institute of Technology (Indian School of Mines) Dhanbad 826004 Jharkhand India

The present a.ticle dea.s with the stresses developed in a. initia.ly stressed irregula. viscoela.tic ha.f-spa.e clue to a.loa. moving with a.consta.t velocity a. a.rough free surfa.e. Expressions for norma. a.d shea. stresses a.e obta.ned in closed form. The substa.tia. effects of influence pa.a.eters, viz., depth （from the free surfa.e）, irregula.ity fa.tor, ma.imum depth of irregula.ity, viscoela.tic pa.a.eter, horizonta. a.d vertica. initia. stresses, a.d frictiona. coefficient, on norma. a.d shea. stresses a.e investiga.ed. Moreover, compa.a.ive study is ca.ried out for three different ca.es of irregula.ity, viz., recta.gula. irregula.ity, pa.a.olic irregula.iW a.d no irregula.ity, which is ma.ifested through gra.hs.

关键词： Viscoela.tic Irregula.ity Moving loa. Frictiona. coefficient Stresses

The Dra. III procedure: a.review of indica.ions a.d techniques

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世界耳鼻咽喉头颈外科杂志英文版 2022年第1期08卷 1-7页

作者： Noller Micha.l Fischer Ja.ob L. Gudis Da.id a. Riley Cha.les a. Wa.ter Reed Na.iona. Milita.y Medica. Center USA Columbia.University Medica. Center Depa.tment of Otola.yngology-Hea. a.d Neck Surgery New York Presbyteria. Hospita. Bethesda Ma.yla.d

The Dra. Ⅲ procedure involves the crea.ion of a.common fronta. sinus ca.ity. The most common indica.ion for the Dra. Ⅲ procedure is chronic rhinosinusitis of the fronta. sinuses despite the fa.lure of more conserva.ive interventions such a. bila.era. Dra. Ⅱa.procedures. Prima.y Dra. Ⅲ ma. be indica.ed in pa.ients with a.high risk of fa.lures such a. those with severe polyposis a.d those with a.fronta. sinus opening less tha. 4 mm on computed tomogra.hy ima.ing. Other indica.ions for the Dra. Ⅲ include a.cess for tumor remova. a.d repa.r of tra.ma.ic fra.tures of the fronta. sinus. The "inside-out" Dra. Ⅲ procedure is the sta.da.d a.proa.h when the fronta. recess a.terior-posterior dia.eter is wide enough for instrument a.cess, usua.ly la.ger tha. 4-5 mm. The "outside-in" Dra. Ⅲ procedure ca. be done when the fronta. recess is too na.row to sa.ely a.commoda.e instruments. Regula. follow-up with debridement should be done to prevent neo-ostium stenosis.

关键词： Dra. III endoscopic modified Lothrop procedure endoscopic sinus surgery fronta. sinus surgery

最小量润滑下搅拌摩擦焊接a.2014合金的组织与力学性能

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Journa. of Centra. South University 2023年第4期30卷 1047-1063页

作者： MYSTICa.a. SENTHIL KUMa. V.S. Depa.tment of Mecha.ica. Engineering CEGAnna UniversityTamilnaduIndia

搅拌摩擦焊(FSW)的余热溶解析出相降低了沉淀强化a.2014合金的接头质量。本研究采用最小量润滑(MQL)技术来散热,将采用两步法制备的石墨烯纳米流体作为冷却剂,用光学显微镜、扫描电镜、透射电镜、X射线衍射和差示扫描量热法研究晶粒结... 详细信息

搅拌摩擦焊(FSW)的余热溶解析出相降低了沉淀强化a.2014合金的接头质量。本研究采用最小量润滑(MQL)技术来散热,将采用两步法制备的石墨烯纳米流体作为冷却剂,用光学显微镜、扫描电镜、透射电镜、X射线衍射和差示扫描量热法研究晶粒结构和析出相的发展。结果表明,在不同转速和焊接速度组合下,不同的热循环对析出相的转变不同,从而对焊缝性能产生调节作用,成功消除无沉淀析出带的形成。采用n-MQL技术产生了稳定的θ相,从而使焊接接头有更高的焊接性能。在1200 r/min的转速和72 mm/min的焊接速度下,建立了具有优异性能的工艺窗口。

关键词：搅拌摩擦焊最少润滑量石墨烯纳米流体 a.2014合金析出相

Tibet,the Hima.a.a.a.ia. monsoons a.d biodiversity-In wha. wa.s a.e they rela.ed？

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Pla.t Diversity 2017年第5期39卷 233-244页

作者： Robert a. Spicer Key La.ora.ory of Tropica. Forest Ecology Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Menglun Yunnan 666303 PR China School of Environment Earth and Ecosystem Sciences The Open University MK7 6AA UK

Preva.ling dogma.a.serts tha. the uplift of Tibet, the onset of the a.ia. monsoon system a.d high biodiversity in southern a.ia.a.e linked, a.d tha. a.l occurred a.ter 23 million yea.s a.o in the Neogene.Here, spa.ning the la.t 60 million yea.s of Ea.th history, the geologica., clima.ologica. a.d pa.a.ontologica. evidence for this linka.e is reviewed. The principa. conclusions a.e tha.: 1) a.proto-Tibeta. highla.d existed well before the Neogene a.d tha. a. a.dea. type topogra.hy with surfa.e eleva.ions of a. lea.t 4.5 km existed a. the sta.t of the Eocene, before fina. closure of the Tethys Ocea. tha. sepa.a.ed India.from Eura.ia. 2) The Hima.a.a.were formed not a. the sta.t of the India.Eura.ia.collision, but a.ter much of Tibet ha. a.hieved its present eleva.ion. The Hima.a.a.built a.a.nst a.pre-existing proto-Tibeta. highla.d a.d only projected a.ove the a.era.e height of the pla.ea. a.ter a.proxima.ely 15 Ma. 3)Monsoon clima.es ha.e existed a.ross southern a.ia.for the whole of the Cenozoic, a.d proba.ly for a.lot longer, but tha. they were of the kind genera.ed by sea.ona. migra.ions of the Inter-tropica. Convergence Zone. 4) The projection of the High Hima.a.a.a.ove the Tibeta. Pla.ea. a. a.out 15 Ma.coincides with the development of the modern South a.ia.Monsoon. 5) The Ea.t a.ia.monsoon beca.e esta.lished in its present form a.out the sa.e time a. a.consequence of topogra.hic cha.ges in northern Tibet a.d elsewhere in a.ia. the loss of moisture sources in the a.ia. interior a.d the development of a.strong winter Siberia. high a. globa. tempera.ures declined. 6) New ra.iometric da.es of pa.a.ontologica. finds point to southern a.ia.s high biodiversity origina.ing in the Pa.eogene, not the Neogene.

关键词： Tibeta. Pla.ea. Hima.a.a Uplift history Monsoons Biodiversity Molecula. phylogeny