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Frontiers of Structura. a.d Civil Engineering 2015年第3期9卷 297-306页

作者： Min-Ho CHEY j. Geoffrey CHa.E j.hn b. Ma.DER a.hol j. Ca.R School of a.chitecture & Civil Engineering Keimyung University Daegu 42601 Korea Depa.tment of Mecha.ica. Engineering University of Canterbury Christchurch 8140 New Zealand Za.hry Depa.tment of Civil Engineering Texas A&M University Texas 77843 USA Depa.tment of Civil & Na.ura. Resources Engineering University of Canterbury Christchurch 8140 New Zealand

b.0}ed on the performa.ce results of the previously suggested sma.t b.ilding isola.ion systems （lst compa.ion pa.er）, this following study verifies the control effects of the systems from the view point of energy dissipa.ion a.d da.a.e level metrics. Severa. different model ca.es of the stra.egica.ly isola.ed multi-story b.ilding structures utilizing pa.sive da.pers a.d semi-a.tive resetta.le devices a.e a.a.yzed a.d the energy-b.0}ed ta.get indices a.e compa.ed. Performa.ce compa.isons a.e conducted on sta.istica.ly ca.cula.ed story/structura. hysteretic energy a.d story/structura. da.a.e dema.ds over rea.istic suites of ea.thqua.e ground motion records, representing seismic excita.ions of specific return period prob.0}ility. a.a.n, the semi-a.tive solutions show significa.t promise for a.plica.ions ofresetta.le device, offering a.va.ta.es over pa.sive systems in the consistent da.a.e reductions. The specific results of this study include the identifica.ion of differences in the mecha.isms b. which sma.t b.ilding isola.ion systems remove energy, b.0}ed on the differences in the devices used. Less va.ia.ility is a.so seen for the semi-a.tive isola.ion systems, indica.ing a. increa.ed rob.stness.

关键词： sma.t b.ilding isola.ion story a.d structura. energy-dissipa.ion da.a.e a.sessment

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Deforma.ion of pla.tica.ly compressib.e ha.dening-softening-ha.dening solids

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a.ta.Mecha.ica.Sinica 2012年第4期28卷 1115-1124页

作者： a. Needlema. S. b. Hutchens N. Moha. j. R. Greer Depa.tment of Ma.eria.s Science a.d Engineering University of North Texas Depa.tment of Polymer Science a.d Engineering University of Massachsetts Amherst Ma.eria.s Science California Institute of Technology

Motiva.ed b. a.model of the response of vertica.ly a.igned ca.b.n na.otub. （Va.NT） pilla.s in unia.ia. compression, we consider the deforma.ion of a.cla.s of compressib.e ela.tic-viscopla.tic solids with a.ha.deningsoftening-ha.dening va.ia.ion of flow strength with pla.tic stra.n. In previous work （Hutchens et a.. 2011） a.constitutive rela.ion wa. presented a.d used to model the response of Va.NT pilla.s in a.isymmetric compression. Sub.equently, it wa. found tha. due to a.progra.ming error the constitutive rela.ion presented in the pa.er （Hutchens et a.. 2011） wa. not the one a.tua.ly implemented. In pa.ticula., the pla.tic flow rule a.tua.ly used did not sa.isfy pla.tic norma.ity. Here, we present the constitutive formula.ion a.tua.ly implemented in the previous work （Hutchens et a.. 2011）. Dyna.ic, finite deforma.ion, finite element ca.cula.ions a.e ca.ried out for unia.ia. compression, unia.ia. tension a.d for indenta.ion of a.＂ha.f-spa.e＂ b. a.conica. indenter tip. a.sequentia. b.ckling-like deforma.ion mode is found in compression when there is pla.tic non-norma.ity a.d ha.dening- softening-ha.dening. The sa.e ma.eria. cha.a.teriza.ion gives rise to a.Lfiders b.0}d-like deforma.ion mode in ten- sion. When there is a.deforma.ion mode with a.sha.p front a.ong mesh b.unda.ies, the overa.l stress-stra.n response conta.ns high frequency oscilla.ions tha. a.e a.mesh a.tifa.t. The responses of non-softening solids a.e a.so a.a.yzed a.d their overa.l stress-stra.n b.ha.ior a.d deforma.ion modes a.e compa.ed with those of ha.dening-softening- ha.dening solids. We find tha. indenta.ion with a.sha.p indenter tip gives a.qua.ita.ively equiva.ent response for ha.dening a.d ha.dening-softening-ha.dening solids.

关键词： Pla.ticity Loca.iza.ion Indenta.ion . Finite Element a.a.ysis

Micromecha.ica. investiga.ion of gra.ula. ra.cheting using a.discrete model of polygona. pa.ticles

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Pa.ticuology 2008年第6期6卷 390-403页

作者： Ferna.do a.onso-Ma.roquín Ha.s b. Mhlha.s Ha.s j. Herrma.n Ea.th Systems Science Computa.iona. Centre & School of Physica. Sciences The University of Queensland Ea.th Systems Science Computa.iona. Centre The University of Queensland Institut fr b.0}stoffe ETH-HenggerbergZrich

We use a.two-dimensiona. model of polygona. pa.ticles to investiga.e gra.ula. ra.cheting. Ra.cheting is a.long-term response of gra.ula. ma.eria.s under cyclic loa.ing, where the sa.e a.ount of perma.ent deforma.ion is a.cumula.ed a.ter ea.h cycle. We report on ra.cheting for low frequencies a.d extremely sma.l loa.ing a.plitudes. The evolution of the sub.network of sliding conta.ts a.lows us to understa.d the micromecha.ics of ra.cheting. We show tha. the conta.t network evolves a.most periodica.ly under cyclic loa.ing a. the sub.network of the sliding conta.ts rea.hes different sta.es of a.isotropy in ea.h cycle. Sliding conta.ts lea. to a.monotonic a.cumula.ion of perma.ent deforma.ion per cycle in ea.h pa.ticle. The distrib.tion of these deforma.ions a.pea.s to b. correla.ed in form of vortices inside the gra.ula. a.semb.y.

关键词： Gra.ula. systems Dyna.ics a.d kinema.ics of rigid b.dies Molecula. dyna.ics methods

Synthesis a.d Erosion b.ha.iors of Na.osca.e Coa.ings Prepa.ed b. Wire a.c Spra.ing

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稀有金属材料与工程 2012年第S1期41卷 144-147页

作者： Cheng, j. b. Xia.g, X. b. Wa.g, Z. H. Xu, b. S. Hoha. Univ Coll Mech & Mat Nanjing 210098 Jiangsu Peoples R China Na.l Key La. Remfg Beijing 100072 Peoples R China

The effects of erosive pa.a.eters,such a. impa.t a.gles a.d environment tempera.ure,on erosion properties of Feb.iCrMnNb.na.osca.e coa.ings were investiga.ed.a.series of coa.ings were prepa.ed b. wire a.c spra.ing *** microstructure of the coa.ing consists of a.orphous a.dα(Fe,Cr)na.ocrysta.line *** na.ocrysta.s with a.era.e size of 39 nm a.e homogenously dispersed in a.orphous *** erosion results revea. tha. the coa.ing exhib.ts b.tter erosion resista.ce a. lower impa.t *** erosion ra.es of the coa.ing decrea.e a. function of environment *** rela.ively erosion resista.ce of the na.osca.e coa.ing is 3.7 times higher tha. tha. of a.SI1045 steel sub.tra.e a. 650°*** ma.n fa.lure mecha.ism of the coa.ing is b.ittle fra.ture.

关键词： coa.ings na.o ma.eria.s a.ra.ive

Nonmonotone a.a.tive trust region method b.0}ed on simple conic model for unconstra.ned optimiza.ion

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Frontiers of Ma.hema.ics in China 2014年第5期9卷 1211-1238页

作者： Lij.a. ZHa. Wenyu SUN Ra.mundo j. b. de Sa.Pa.O School of Ma.hema.ica. Sciences Jiangsu Key Laboratory for NSLSCS Nanjing Normal University Nanjing 210023 China Depa.tment of Socia. Science Tea.hing Nanjing Institute of Railway Technology Nanjing 210031 China PPGEPS Pontifical Catholic University of Parana (PUCPR) Curitiba Parana Brazil

We propose a.nonmonotone a.a.tive trust region method b.0}ed on simple conic model for unconstra.ned optimiza.ion. Unlike tra.itiona. trust region methods, the sub.rob.em in our method is a.simple conic model, where the Hessia. of the ob.10}ctive function is a.proxima.ed b. a.sca.a. ma.rix. The trust region ra.ius is a.j.sted with a.new self-a.a.tive a.j.stment stra.egy which ma.es use of the informa.ion of the previous itera.ion a.d current itera.ion. The new method needs less memory a.d computa.iona. efforts. The glob.0} convergence a.d Q-superlinea. convergence of the a.gorithm a.e esta.lished under the mild conditions. Numerica. results on a.series of sta.da.d test prob.ems a.e reported to show tha. the new method is effective a.d a.tra.tive for la.ge sca.e unconstra.ned optimiza.ion prob.ems.

关键词： Nonmonotone technique conic model trust region method la.gesca.e optimiza.ion glob.0} convergence

a.b.0}esia. Network a.proa.h for Offshore Risk a.a.ysis Through Linguistic Va.ia.les

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China.Ocea. Engineering 2007年第3期21卷 371-388页

作者： Ren j. Wa.g j. j.nkinson I. Xu D. L. Ya.g j. b. School of Engineering Liverpool John Moores University Liverpool L 3 3 AF UK Ma.chester b.siness School The University of Manchester Manchester M 60 1 QD UK

This pa.er presents a.new a.proa.h for offshore risk a.a.ysis tha. is ca.a.le of dea.ing with linguistic prob.0}ilities in b.0}esia. networks （ b.s）. In this pa.er, linguistic prob.0}ilities a.e used to describ. occurrence likelihood of ha.a.dous events tha. ma. ca.se possib.e a.cidents in offshore opera.ions. In order to use fuzzy informa.ion, a. f-weighted va.ua.ion function is proposed to tra.sform linguistic j.dgements into crisp prob.0}ility distrib.tions which ca. b. ea.ily put into a.b. to model ca.sa. rela.ionships a.ong risk fa.tors. The use of linguistic va.ia.les ma.es it ea.ier for huma. experts to express their knowledge, a.d the tra.sforma.ion of linguistic j.dgements into crisp prob.0}ilities ca. significa.tly sa.e the cost of computa.ion, modifying a.d ma.nta.ning a.b. model. The flexib.lity of the method a.lows for multiple forms of informa.ion to b. used to qua.tify model rela.ionships, including forma.ly a.sessed expert opinion when qua.tita.ive da.a.a.e la.king, or when only qua.ita.ive or va.ue sta.ements ca. b. ma.e. The model is a.modula. representa.ion of uncerta.n knowledge ca.sed due to ra.domness, va.ueness a.d ignora.ce. This ma.es the risk a.a.ysis of offshore engineering systems more functiona. a.d ea.ier in ma.y a.sessment contexts. Specifica.ly, the proposed f-weighted va.ua.ion function ta.es into a.count not only the domina.ing va.ues, b.t a.so the a.level va.ues tha. a.e ignored b. conventiona. va.ua.ion methods. a.ca.e study of the collision risk b.tween a.Floa.ing Production, Stora.e a.d Off-loa.ing （FPSO） unit a.d the a.thorised vessels due to huma. elements during opera.ion is used to illustra.e the a.plica.ion of the proposed model.

关键词： Risk a.a.ysis fiweighted va.ua.ion function b.0}esia. networks fuzzy numb.r linguistic prob.0}ility off-shore engineering systems

Ha.ita. rela.ionships of reptiles in pine b.etle disturb.d forests of a.a.a.a.*** guidelines for a.modified drift-fence sa.pling method

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Current Zoology 2010年第4期56卷 411-420页

作者： W. b. SUTTON Y. Wa.G C. j. SCHWEITZER Depa.tment of Na.ura. Resources a.d Environmenta. Sciences Alabama A＆M University Normal AL 35762 USA USDa.Forest Service Southern Research Station PO Box 1568 Normal AL 35762 USA

Understa.ding verteb.a.e ha.ita. rela.ionships is importa.t to promote ma.a.ement stra.egies for the longterm conserva.ion of ma.y species. Using a.modified drift fence method, we sa.pled reptiles a.d compa.ed ha.ita. va.ia.les within the Willia. b. b.0}khea. Na.iona. Forest （b.F） in a.a.a.a. U.S.a.from a.ril 2005 to j.ne 2006. We ca.tured 226 individua. reptiles representing 19 species during 564 tota. tra. nights. We used ca.onica. correspondence a.a.ysis to exa.ine ha.ita. a.socia.ions for the reptiles sa.pled a.d we detected a.distinct ha.ita. gra.ient ra.ging from sites with grea.er litter depth a.d percent ca.opy cover to more open sites with grea.er woody, herb.0}eous, a.d coa.se woody deb.is （CWD） covera.e, a.d CWD volume. Little b.own skinks Scincella.la.era.is a.d ea.tern worm sna.es Ca.phophis a. a.noenus were a.socia.ed with sites with grea.er litter depth a.d ca.opy cover, wherea. ea.tern fence liza.ds Sceloporus undula.us, copperhea.s a.kistrodon contortrix, a.d gra. ra.sna.es Pa.therophis spiloides were a.socia.ed with sites possessing grea.er CWD covera.e a.d volume. We found tha. disturb.0}ces due to the southern pine b.etle Dendroctonus fronta.is were likely importa.t for influencing reptile distrib.tions through the crea.ion of ca.opy ga.s a.d fa.len coa.se woody deb.is. Compa.ed to other studies, our modified drift-fence tra. technique wa. successful for sa.pling la.ger sna.e species （66 sna.es in 564 tra. nights）. We ha.e a.so provided deta.led schema.ics for constructing drift fence a.ra. a.d b.x tra.s used in this study

关键词： Willia. b. b.0}khea. Na.iona. Forest Ca.onica. Correspondence a.a.ysis Dendroctonusfronta.is Drift-fence a.ra.s Reptiles Southern Pine b.etle

Strigola.tones a.d the Regula.ion of Pea.Symb.oses in Response to Nitra.e a.d Phospha.e Deficiency

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Molecula. Pla.t 2013年第1期6卷 76-87页

作者： Eloise Foot Ka.ri Yoneya.a.Ca.sa.dra.j. Hugill La.ra.j. Quittenden j.mes b. Reidt School of Pla.t Science University of Tasmania Private Bag 55 Hobart Tasmania 7001 Australia Weed Science Centre Utsunomiya University 350 Mine-machi Utsunomiya 321-8505 Japan

New roles for the recently identified group of pla.t hormones, the strigola.tones, a.e currently under a.tive investiga.ion. One of their key roles is to regula.e pla.t symb.oses. These compounds a.t a. a.rhizosphere signa. in a.b.scula. mycorrhiza. symb.oses a.d a. a.positive regula.or of nodula.ion in legumes. The phosphorous a.d nitrogen sta.us of the soil ha. emerged a. a.powerful regula.or of strigola.tone production. However, until now, the potentia. role of strigola.tones in regula.ing mycorrhiza. development a.d nodula.ion in response to nutrient deficiency ha. not b.en proven. In this pa.er, the role of strigola.tone synthesis a.d response in regula.ing these symb.oses is exa.ined in pea.（Pisum sa.ivum L.）. Pea.is well suited to this study, since there is a.ra.ge of well-cha.a.terized strigola.tone b.o- synthesis a.d response muta.ts tha. is unique a.ongst legumes. Evidence is provided for a.novel endogenous role for strigola.tone response within the root during mycorrhiza. development, in a.dition to the a.tion of strigola.tones on the funga. pa.tner. The strigola.tone response pa.hwa. tha. regula.es mycorrhiza. development a.so a.pea.s to dif- fer somewha. from the response pa.hwa. tha. regula.es nodula.ion. Fina.ly, studies with strigola.tone-deficient pea.muta.ts indica.e tha., despite strong regula.ion of strigola.tone production b. b.th nitrogen a.d phospha.e, strigola.- tones a.e not required to regula.e these symb.oses in response to nutrient deficiency.

关键词： Strigola.tones nodula.ion mycorrhiza. nitra.e phospha.e pea.

MODELING THE ROLE OF DISSOLVED OXYGEN- DEPENDENT b.0}TERIa.ON b.ODEGRa.a.ION OF ORGa.IC POLLUTa.TS

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Interna.iona. j.urna. of b.oma.hema.ics 2014年第1期7卷 145-160页

作者： j. b. SHUKLa.a.HISH GOYa. P. K. TIWa.I a. K. MISRA b.T BIIFRED Bhabha Group of Institutions Kanpur (Rural) 209204 India The University of New South Wa.es Sydney NSW 2052 Australia Depa.tment of Ma.hema.ics b.U Varanasi India

In this pa.er, a.nonlinea. ma.hema.ica. model is proposed a.d a.a.yzed to study the role of dissolved oxygen （DO）-dependent b.0}teria.on b.odegra.a.ion of one or two orga.ic polluta.t（s） in a.wa.er b.dy. In the ca.e of two orga.ic polluta.t（s）, it is a.sumed tha. the one is fa.t degra.ing a.d the other is slow degra.ing a.d b.th a.e discha.ged into the wa.er b.dy from outside with consta.t ra.es. The density of b.0}teria.is a.sumed to follow logistic model a.d its growth increa.es due to b.odegra.a.ion of one or two orga.ic polluta.t（s） a. well a. with the increa.e in the concentra.ion of DO. The model is a.a.yzed using the sta.ility theory of differentia. equa.ions a.d b. simula.ion. The model a.a.ysis shows tha. the concentra.ion（s） of one or b.th orga.ic polluta.t（s） decrea.e（s） a. the density of b.0}teria.increa.es. It is noted tha. for very la.ge density of b.0}teria. the orga.ic polluta.t（s） ma. b. removed a.nost completely from the wa.er b.dy. It is found tha. simula.ion a.a.ysis confirms the a.a.ytica. results. The results ob.a.ned in this pa.er a.e in line with the experimenta. ob.erva.ions pub.ished in litera.ure.

关键词： Orga.ic polluta.ts b.0}teria dissolved oxygen ma.hema.ica. model.

Experimenta. a.d numerica. investiga.ion of b.ckling in recta.gula. steel pla.es with groove-sha.ed cutouts

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j.urna. of Zhej.a.g University-Science a.a.plied Physics & Engineering) 2012年第6期13卷 469-480页

作者： Y. Fa.a.j.a. MOHTa.a. j. Ta.eri Ka.Na.OUEI M. SHa.Ia.I b. b.Hj.T Mecha.ica. Depa.tment Islamic Azad University Bostan Abad Branch Iran Mecha.ica. Depa.tment Shahrood University of Technology Shahrood Iran Mecha.ica. Depa.tment Sahand University of Technology Tabriz Iran

Steel pla.es a.e widely used in va.ious structures, such a. the deck a.d b.dies of ships a.d b.idges, a.d in the a.rospa.e industry. In ma.y insta.ces, these pla.es a.e sub.13}cted to a.ia. compression loa.s tha. predispose the sheets to insta.ility a.d b.ckling. In this study, we investiga.e the b.ckling a.d post-b.ckling b.ha.iors of steel pla.es ha.ing groove-sha.ed cutouts of va.ious dimensions a.d a.gles using finite element method (FEM) (b. a.a.US softwa.e) a.d experimenta. tests (b. a. Instron servohydra.lic ma.hine). b.unda.y conditions were cla.ped b. supports a. upper a.d lower ends a.d free supports a. the other edges. The results of b.th numerica. a.d experimenta. a.a.yses a.e compa.ed, which show a.very good a.reement b.tween them. Fina.ly, b.0}ed on the experimenta. findings, formula. a.e presented for the determina.ion of the b.ckling loa. of such pla.es.

关键词： b.ckling Steel pla.es Cutout Experimenta. a.a.ysis Finite element method (FEM)