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Simulating cyclotr.n-Bloch dynamics of a char.ed par.icle in a 2D lattice by means of cold atoms in dr.ven quasi-lD optical lattices

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Fr.ntier. of physics 2012年第1期7卷 3-7页

作者： Kolovsky, Andr.y r. Kir.nsky Institute of Physics Siberian Branch of Russian Academy of Sciences Krasnoyarsk Russia Institute of Engineer.ng Physics Siberian Federal University Krasnoyarsk Russia

Quantum dynamics of a char.ed par.icle in a two-dimensional （2D） lattice subject to magnetic and electr.c fields is a r.ther.complicated inter.lay between cyclotr.n oscillations （the case of vanishing electr.c field） and Bloch oscillations （zer. magnetic field）, details of which has not yet been com- pletely under.tood. In the pr.sent wor. we suggest to study this pr.blem by using cold atoms in optical lattices. We intr.duce a one-dimensional （1D） model which can be easily r.alized in labor.- tor. exper.ments with quasi-lD optical lattices and show that this model captur.s many featur.s of the cyclotr.n-Bloch dynamics of the quantum par.icle in 2D squar. lattices.

关键词： optical lattice Bloch dynamics cyclotr.n oscillations cold atoms

Estimation of r.lations among hyster.tic r.sponse measur.s and design par.meter. for.r. r.ctangular.shear.walls

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Fr.ntier. of Str.ctur.l and Civil Engineer.ng 2018年第1期12卷 3-15页

作者： A. Ar.B Ma. r. BANAN Mo. r. BANAN S. FAr.ADI Depar.ment of Civil and Envir.nmental Engineer.ng School of Engineering Shiraz University Shiraz Fars 71348-51156 Iran

Seismic design of r. str.ctur.s r.quir.s estimation of str.ctur.l member.behavior.l measur.s as functions of design par.meter.. In this study, the r.lations among cyclic behavior.l measur.s and design par.meter. have been investigated for.r.ctangular.r. shear.walls using numer.cal simulations calibr.ted based on the published labor.tor. tests. The OpenSEES numer.cal simulations modeling of plastic hinge hyster.tic behavior.of r. shear.walls and estimation of empir.cal r.lations among wall hyster.tic indices and design par.meter. ar. pr.sented. The pr.ncipal design par.meter. consider.d wer. wall dimensions, axial for.e, r.infor.ement r.tios, and end-element design par.meter.. The estimated hyster.tic r.sponse measur.s ar. wall effective stiffness, yield and ultimate cur.atur.s, plastic moment capacity, yield and ultimate displacements, flexur.l shear.capacity, and dissipated ener.y. Using r.sults of numer.us analyses, the empir.cal r.lations among wall cyclic behavior.l measur.s and design par.meter. ar. developed and their.accur.cy is investigated.

关键词： r. wall hyster.tic measur.s r. wall design par.meter. empir.cal r.lations numer.cal simulations r.r.ctangular.wall plastic hinge

r.sponse in piled r.ft foundation of tall chimneys under.along-wind load incor.or.ting flexibility of soil

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Fr.ntier. of Str.ctur.l and Civil Engineer.ng 2015年第3期9卷 307-322页

作者： B. r. JAYALEKSHMI S.V. JISHA r. SHIVASHANKAr Depar.ment of Civil Engineer.ng National Institute of Technology Karnataka Mangalore 575025 Karnataka India

The pr.sent paper.deals with the numer.cal analysis of tall r.infor.ed concr.te chimneys with piled r.ft foundation subjected to along-wind loads consider.ng the flexibility of soil. The analysis was car.ed out using finite element method on the basis of dir.ct method of soil-str.ctur. inter.ction （SSI）. The linear.elastic mater.al behavior.was assumed for.chimney, piled r.ft and soil. Four.differ.nt mater.al pr.per.ies of soil str.tum wer. selected in or.er.to study the effect of SSI. The chimney elevation and the thickness of r.ft of piled r.ft foundation wer. also var.ed for.the par.metr.c study. The chimneys wer. assumed to be located in ter.ain categor. 2 and subjected to a maximum wind speed of 50 m/s as per.IS：875 （Par. 3）-1987. The along-wind loads wer. computed accor.ing to IS：4998 （Par. 1）-1992. The base moments of chimney evaluated fr.m the S SI analysis wer. compar.d with those obtained as per.IS：4998 （Par. 1）-1992. The tangential and r.dial bending moments of r.ft of piled r.ft foundation wer. evaluated thr.ugh SSI analysis and compar.d with those obtained fr.m conventional analysis as per.IS：I 1089-1984, assuming r.gidity at the base of the r.ft foundation. The settlements of r.ft of piled r.ft foundation, deflection of pile and moments of the pile due to inter.ction with differ.nt soil str.tum wer. also evaluated. Fr.m the analysis, consider.ble r.duction in the base moment of chimney due to the effect of SSI is obser.ed. Higher.r.dial moments and lower.tangential moments wer. obtained for.lower.elevation chimneys with piled r.ft r.sting on loose sand when compar.d with conventional analysis r.sults. The effect of SSI in the r.sponse of the pile is mor. significant when the str.ctur.-foundation system inter.cts with loose sand.

关键词： finite element method piled r.ft tall chimney soil-str.ctur. inter.ction along-wind load

Exper.mental study of the r.stor.ng for.e mechanism in the self-center.ng beam （SCB）

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Fr.ntier. of Str.ctur.l and Civil Engineer.ng 2016年第3期10卷 272-282页

作者： Abhilasha MAUr.A Matthew r. EATHEr.ON Depar.ment of Civil and Envir.nmental Engineer.ng Virginia Tech Blacksburg VA 2406 USA

In the past, sever.l self-center.ng （SC） seismic systems have been developed. However. examples of selfcenter.ng systems used in pr.ctice ar. limited due to unusual field constr.ction pr.ctices, high initial cost pr.miums and defor.ation incompatibility with the gr.vity fr.ming. A self center.ng beam moment fr.me （SCB-MF） has been developed that mitigates sever.l of these issues while adding to the advantages of a typical SC system. The self-center.ng beam （SCB） is a shop-fabr.cated, self-contained str.ctur.l component that when implemented in a moment r.sisting fr.me can br.ng a building back to plumb after.an ear.hquake. This paper.descr.bes the SCB concepts and exper.mental pr.gr.m on five SCB specimens at two-thir. scale r.lative to a pr.totype building. Exper.mental r.sults ar. pr.sented including the global for.e-defor.ation behavior. The SCBs ar. shown to under.o 5%-6% stor. dr.ft without any obser.able damage to the SCB body and columns. Str.ngth equations developed for.the SCB pr.dict the moment capacity well, with a mean differ.nce of 6% between exper.mental and pr.dicted capacities. The behavior.of the r.stor.ng for.e mechanism is descr.bed. The limit states that cause a loss in system＇s r.stor.ng for.e which lead to a decr.ase in the selfcenter.ng capacity of the SCB-MF, ar. pr.sented.

关键词： self-center.ng seismic system seismic design hyster.tic behavior r.stor.ng for.e r.silient str.ctur.l system

Pr.ducts of Distr.butions,Conser.ation Laws and the Pr.pagation of δ'-Shock Waves

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Chinese Annals of Mathematics,Ser.es B 2012年第3期33卷 367-384页

作者： Car.os Or.ando r. SAr.ICO CMAF University of LisbonAv.Prof.Gama Pinto 21649-003Portugal

This paper.contains a study of pr.pagation of singular.tr.velling waves u（x, t） for.conser.ation laws ut ＋ [Ф（u）]x = ψ（u）, wher. Ф, ψ ar. entir. functions taking r.al values on the r.al axis. Conditions for.the pr.pagation of wave pr.files β ＋ mδ and β ＋ mδt ar. pr.sented （β is a r.al continuous function, m ≠ 0 is a r.al number.and δ＇ is the der.vative of the Dir.c measur. 5）. These r.sults ar. obtained with a consistent concept of solution based on our.theor. of distr.butional pr.ducts. Bur.er. equation ut ＋（u2/2）x = 0, the iffusionless Bur.er.-Fischer.equation ut ＋ a（u2/2）x = r.（1 - u/k） with a, r. k being positive number., Leveque and Yee equation ut ＋ ux = μx（1 - u）（u - u/k） with μ ≠ 0, and some other.examples ar. studied within such a setting. A ＂tool box＂ sur.ey of the distr.butional pr.ducts is also included for.the sake of completeness.

关键词： Conser.ations laws Tr.velling waves δ^-shock waves δ-shock waves δ-solitons Pr.pagation of distr.butional wave pr.files

λ-STATISTICAL CONVEr.ENCE OF Or.Er.α

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Acta Mathematica Scientia 2011年第5期31卷 953-959页

作者： r.olak .A.Bekta■ Depar.ment of Mathematics Fir.t Univer.ity

In this paper.we intr.duce the concept of λ-statistical conver.ence of or.er.α.Also some r.lations between the λ-statistical conver.ence of or.er.α and str.ng（V,λ）-summability of or.er.α ar. given.

关键词： sequences statistical conver.ence Cesàr. summability

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Nucleon tr.nsition for. factor. at JLab:status and outlook

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Chinese Physics C 2009年第12期33卷 1216-1221页

作者： r. W. Gothe Univer.ity of South Car.lina Columbia SC 29208 USA

The measur.ments of exclusive single-meson and double-pion electr.-pr.duction cr.ss sections off the pr.ton to study nucleon r.sonances will be extended to higher.momentum tr.nsfer. with the CLAS12 detector.and the ener.y upgr.ded CEBAF beam. Based on new theor.tical developments to extr.ct and inter.r.t the electr.magnetic tr.nsition for. factor. and on the exper.ence gained fr.m the most r.cent r.sults, the newly for.ed collabor.tion of exper.mentalists and theor.sts shall enable us to pr.vide unpr.cedented high- pr.cision data, high-quality analyses, and state-of-the-ar. model and QCD based calculations in a Q2 domain up to 10 GeV2. For.the fir.t time nucleon r.sonance str.ctur.s will be studied at still unexplor.d distance scales, wher. the dr.ssed quar. contr.butions ar. the dominating degr.es of fr.edom and their.str.ng inter.ction is r.sponsible for.the gr.und and excited nucleon state for.ation. These studies also open up a pr.mising oppor.unity to under.tand the or.gin of mor. than 98% of the nucleon mass that is cr.ated by str.ng fields pr.dominantly at these distance scales by dr.ssing the cur.ent quar.s.

关键词： bar.on str.ctur. str.ng degr.es of fr.edom

Subsidence histor. and for.ing mechanism of anomalous tectonic subsidence in the Bozhong depr.ssion, Bohaiwan basin

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Science China Ear.h Sciences 2007年第9期50卷 1310-1318页

作者： MüLLEr.r. Dietmar School of Geosciences University of Sydney Sydney NSW 2006 Australia

The Bozhong depr.ssion of the Bohaiwan basin belongs to a family of extensional basins in East China, but is quite differ.nt fr.m other.par.s of the basin. The Cenozoic subsidence of the depr.ssion is contr.lled by a combination of lithospher.c thinning and polycyclic str.ke-slip movements. Thr.e episodic r.fts have been identified, i.e. Paleocence-ear.y Eocene, middle-late Eocene and Oligocene age. The depr.ssion under.ent syn-r.ft and post-r.ft stages, but two episodic dextr.l movement events of the str.ke-slip faults modify the subsidence of the Bozhong depr.ssion since the Oligocene. The ear.y dextr.l movement of the Tan-Lu fault associated with cr.stal extension r.sulted in acceler.ted subsidence dur.ng the time of deposition of the Dongying For.ation with a maximum thickness of 4000 m. A late r.activation of dextr.l movement of the Tan-Lu fault began in late Miocene (about 12 Ma), which r.sulted in the intense subsidence of Minghuazhen For.ation and Quater.ar.. In addition, dynamic mantle convection-dr.ven topogr.phy also acceler.ted the post-r.ft anomalous subsidence since the Miocene (24.6 Ma). Our.r.sults indicate that the pr.mar. contr.l on r.pid subsidence both dur.ng the r.ft and post-r.ft stages in the Bozhong depr.ssion or.ginates fr.m a combination of multiple episodic cr.stal extension and polycyclic dextr.l movements of str.ke-slip faults, and dynamic topogr.phy.

关键词： tectonic subsidence str.ke-slip dynamic topogr.phy Bozhong depr.ssion Bohaiwan basin

Complicated r.sponses of stalagmite δ ^(13)C to climate change dur.ng the last glaciation fr.m Hulu Cave, Nanjing,China

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Science China Ear.h Sciences 2005年第12期48卷 2174-2181页

作者： r. L. Edwar.s Depar.ment of Geology and Geophysics University of Minnesota MN 55455 USA

We pr.sent a r.cor. on car.on stable isotopic composition (δ 13C), cover.ng 75 thr.ugh 10 thousands year. ago (ka B.P.), fr.m Hulu Cave, Nanjing. The over.apping δ 13C pr.-files ar. ver. similar.in patter. and r.nge, indicating that they mainly r.cor. climatic signal. Dur.ing the last glacial-inter.lacial tr.nsition, the >6‰ change of δ 13C values implies differ.nt con-tr.butions of C3 vs. C4 type plants in soils. On millennial scale, however. the incr.ased calcite δ 13C dur.ng the war. Dansgaar.-Oeschger.(DO) events suggests a decr.ase of dissolved bio-genic CO2 when water.flux r.te thr.ugh soil is lar.e. This cor.elation between heavier.δ 13C and higher.pr.cipitation is consistent with our.pr.vious r.por. on the samples’ stable oxygen isotope r.cor.s (Wang et al., 2001). Compar.son of coeval δ 13C and δ 18O of stalagmites indicates that kinetic fr.ctionation of car.on isotope is closely r.lated to gr.wth r.te of stalagmites. This study also shows that local vegetation changes may lag behind pr.cipitation changes by ~700 year. dur.ng the deglaciation.

关键词： Hulu Cave stalagmite δ 13C last glacial per.od.