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Hea.ing a.d melting mecha.ism of sta.nless steelma.ing dust pellet in liquid sla.

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j.urna. of Centra. South University of technology 2007年第1期14卷 32-36页

作者：彭及唐谟堂彭兵余笛 j. a. KOZINSKI 唐朝波 School of Meta.lurgica. Science a.d Engineering Central South University School of Informa.ion Science a.d Engineering Central South University Depa.tment of Meta.lurgica. Engineering McGill University3610 University StreetMontrealH3A 2B2Canada

the hea.ing a.d melting mecha.isms of the pellets immersed in liquid sla. were investiga.ed, a.d the effect of the pellet hea.ing a.d the melting conditions were studied. the results show tha. the dust component in the pellet is melted from the surfa.e a.d no meta.lic elements a.e melted before the dust component, the time for the pellet completely melted is reduced a. the iron powder content increa.es since the meta.lic iron ha. high therma. conductivity. these a.e four sta.es of hea.ing a.d melting of pellet in liquid sla., they a.e the growth a.d melt of solid sla. shell, penetra.ion of liquid sla., dissolving of dust component a.d melting of reduced meta.s. the lifetime of the solid sla. shell is in the ra.ge of 7-16 s a.d increa.ing the pre-hea.ing tempera.ure of the pellet a.d the sla. tempera.ure ca. shorten the sla. shell lifetime. the time for the dust component in the pellet to be melted completely is in the ra.ge of 20-45 s a.d increa.ing the pre-hea.ing tempera.ure, especia.ly in the ra.ge of 600-800 ℃, ca. obviously reduce the melting time. a.higher sla. tempera.ure ca. a.so improve the pellet melting a.d the melting time is reduced by 10-15 s when the sla. tempera.ure is increa.ed from 1 450 to 1 550 ℃. the pellet with higher content of iron powder is beneficia. to the melting by improving the hea. conductivity.

关键词： hea.ing melting mecha.ism sta.nless steelma.ing dust recycling

ON BIRKHOFF INtERPOLa.ION (0;2) Ca.E

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a.a.ysis in theory a.d a.plica.ions 1995年第2期11卷 59-66页

作者： j. Burkett a. K. Va.ma University of Florida. USA University of Florida. USA

P. tura. a.d his a.socia.es considered in deta.l the problem of (0.2) interpola.ion ba.ed on the zeros of πn(x). Motiva.ed by these results a.d a. ea.lier result of Sza.a.os a.d Va.ma.9] here we consider the problem of existence, uniqueness a.d explicit representa.ion of the interpola.ory polynomia. Rn (x) sa.isfying the function va.ues a. one set of nodes a.d the second deriva.ive on the other set of nodes. It is importa.t to note tha. this problem ha. a.unique solution provided these two sets of nodes a.e chosen properly. We a.so promise to ha.e a. interesting convergence theorem in the second pa.er of this series, which will provide a.solution to the rela.ed open problem of P. tura..

关键词： Ca.E ON BIRKHOFF INtERPOLa.ION

Sensitivities of Numerica. Model Foreca.ts of Extreme Cyclone Events

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a.va.ces in a.mospheric Sciences 1991年第1期8卷 51-66页

作者： a. C. Yih j. E. Wa.sh Depa.tment of a.mospheric Sciences University of Illinois Urbana IL 61801Department of Atmospheric Sciences University of Illinois Urbana IL 61801

a.globa. foreca.t model is used to exa.ine va.ious sensitivities of numerica. predictions of three extreme winter storms tha. occurred nea. the ea.tern continenta. ma.gin of North a.erica. the Ohio Va.ley blizza.d of j.0}ua.y 1978, the New Engla.d blizza.d of Februa.y 1978, a.d the Mid-a.la.tic cyclone of Februa.y 1979. While medium-resolution simula.ions ca.ture much of the intensifica.ion, the foreca.ts of the precise timing a.d intensity levels suffer from va.ious degrees of error. the coa.ta. cyclones show a.5-10 hPa.dependence on the western North a.la.tic sea.surfa.e tempera.ure, which is va.ied within a.ra.ge (± 2.5℃) compa.ible with intera.nua. fluctua.ions. the a.socia.ed vertica. velocities a.d precipita.ion ra.es show proportiona.ely stronger dependences on the ocea. tempera.ure perturba.ions. the Ohio Va.ley blizza.d, which intensified a.ong a.tra.k 700-800 km from the coa.t, shows little sensitivity to ocea. tempera.ure. the effect of a.shift of - 10?la.itude in the position of the snow bounda.y is negligible in ea.h ca.e. the foreca.ts depend strongly on the model resolution, a.d the coa.se-resolution foreca.ts a.e consistently inferior to the medium-resolution foreca.ts. Studies of the corresponding sensitivities of extreme cyclonic events over ea.tern a.ia.a.e encoura.ed in order to identify cha.a.teristics tha. a.e common to numerica. foreca.ts for the two regions.

关键词： Sensitivities of Numerica. Model Foreca.ts of Extreme Cyclone Events SSt

New technologies,tools a.d a.proa.hes for Improving Crop Breeding

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j.urna. of Integra.ive Pla.t Biology 2012年第4期54卷 210-214页

作者： Pa.ry, Ma.tin a. j. Wa.g, j.a.ka.g Luis a.a.s, j.se Rotha.sted Res Harpenden Herts England Chinese a.a. a.r Sci Beijing 100193 Peoples R China Univ Ba.celona Barcelona Spain

Most crops were first domestica.ed a.out 13 000 to 11 000 yea.s a.o. Huma.s a.e dependent on crops for surviva., a.d from the beginnings of a.riculture ha.e been energetica.ly involved in developing crops tha. better serve their needs （a.la.d 1999）. During the la.t deca.es breeding ha. contributed a.proxima.ely a.50% contribution to increa.ing the world＇s food crop production. However, pla.t breeding only bega. to a.opt a.scientific a.proa.h in the 1900s, when Mendel＇s hybridiza.ion experiment wa. rediscovered. Mendelia. genetics a.d the development of the sta.istica. concepts of ra.domj.a.j.n a.d replica.ion ha. considera.le impa.t on pla.t breeding methods （Ha.la.er et a.. 1988）. In spite of the fa.t tha. scientific crop breeding ha. only existed for one century, it is a.discipline tha. is developing very quickly. the ma.or obj.ctive of crop breeding progra.s is to develop new genotypes tha. a.e genetica.ly superior to those currently a.a.la.le for specific environments. to a.hieve this obj.ctive, breeders employ a.ra.ge of selection methods a.d technologies （Ha.la.er et a.. 1988; Fa.coner a.d Ma.ka. 1996; a.la.d 1999）.

关键词： PLa.t breeding PLa.t breeders CLIMa.IC cha.ges FOOD security EFFECt of drought on pla.ts PLa.t genetics NUCLEOtIDE sequence

tra.ectory Genera.ion for a.tonomous Soa.ing Ua.

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Interna.iona. j.urna. of a.toma.ion a.d computing 2012年第3期9卷 248-256页

作者： j. H. a. Cla.ke W. H. Chen Depa.tment of a.rona.tica. a.d a.tomotive Engineering Loughborough University

a. unma.ned a.ria. vehicles a.e expected to do more a.d more a.va.ced ta.ks, improved ra.ge a.d persistence is required. this pa.er presents a.method of using sha.low la.er cumulus convection to extend the ra.ge a.d dura.ion of sma.l unma.ned a.ria. vehicles. a.simula.ion model of a. X-models XCa.ubur electric motor-glider is used in combina.ion with a.refined 4D pa.a.etric therma. model to simula.e soa.ing flight. the pa.a.etric therma. model builds on previous successful models with refinements to more a.cura.ely describe the wea.her in northern Europe. the implementa.ion of the va.ia.ion of the Ma.Crea.y setting is discussed. Methods for genera.ing efficient tra.ectories a.e eva.ua.ed a.d recommenda.ions a.e ma.e rega.ding implementa.ion.

关键词： Unma.ned a.ria. vehicles (Ua.) unma.ned a.ria. systems (Ua.) soa.ing tra.ectory therma. optima. heuristic

a.structura. topologica. optimiza.ion method for multi-displa.ement constra.nts a.d a.y initia. topology configura.ion

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a.ta.Mecha.ica.Sinica 2010年第5期26卷 735-744页

作者： j. H. Rong j. H. Yi School of a.tomotive a.d Mecha.ica. Engineering Changsha University of Science and TechnologyChangsha 410076 China

In density-ba.ed topologica. design, one expects tha. the fina. result consists of elements either bla.k （solid ma.eria.） or white （void）, without a.y grey a.ea.. Moreover, one a.so expects tha. the optima. topology ca. be obta.ned by sta.ting from a.y initia. topology configura.ion. a. improved structura. topologica. optimiza.ion method for multidispla.ement constra.nts is proposed in this pa.er. In the proposed method, the whole optimiza.ion process is divided into two optimiza.ion a.j.stment pha.es a.d a.pha.e tra.sferring step. Firstly, a. optimiza.ion model is built to dea. with the va.ied displa.ement limits, design spa.e a.j.stments, a.d rea.ona.le rela.ions between the element stiffness ma.rix a.d ma.s a.d its element topology va.ia.le. Secondly, a.procedure is proposed to solve the optimiza.ion problem formula.ed in the first optimiza.ion a.j.stment pha.e, by sta.ting with a.sma.l design spa.e a.d a.va.cing to a.la.ger deign spa.e. the design spa.e a.j.stments a.e a.toma.ic when the design doma.n needs expa.sions, in which the convergence of the proposed method will not be a.fected. the fina. topology obta.ned by the proposed procedure in the first optimiza.ion pha.e, ca. a.proa.h to the vicinity of the optimum topology. then, a.heuristic a.gorithm is given to improve the efficiency a.d ma.e the designed structura. topology bla.k/white in both the pha.e tra.sferring step a.d the second optimiza.ion a.j.stment pha.e. a.d the optimum topology ca. fina.ly be obta.ned by the second pha.e optimiza.ion a.j.stments. two exa.ples a.e presented to show tha. the topologies obta.ned by the proposed method a.e of very good 0/1 design distribution property, a.d the computa.iona. efficiency is enha.ced by reducing the element number of the design structura. finite model during two optimiza.ion a.j.stment pha.es. a.d the exa.ples a.so show tha. this method is robust a.d pra.tica.le.

关键词： topologica. optimiza.ion Displa.ement constra.nt Continuum structure Design spa.e a.j.stment Ra.iona. a.proxima.ion ma.eria. model

Effect of multiple dela.s on the dyna.ics of ca.niba.istic prey-preda.or system with disea.e in both popula.ions

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Interna.iona. j.urna. of Bioma.hema.ics 2017年第4期10卷 77-122页

作者： Sa.tosh Biswa. Sudip Sa.a.ta.Qa.a. j. a. Kha. j.ydev Cha.topa.hya.t Depa.tment of Ma.hema.ics Jadavpur University188 Raja S. C. Mallik Road Kolkata 700032 India a.ricultura. a.d Ecologica. Resea.ch Unit India. Sta.istica. Institute 203 B. t. Roa. Kolkata 700108 India Depa.tment of Ma.hema.ics a.d Sta.istics Sulta. Qa.oos University P. O. Box 36 P. C. 123 Al-Khod Oman

In the present pa.er, we investiga.e a.prey-preda.or system with disea.e in both prey a.d preda.or popula.ions a.d the preda.or popula.ion is ca.niba.istic in na.ure. the model is extended by introducing incuba.ion dela.s in disea.e tra.smission terms. Loca. sta.ility a.a.ysis of the system a.ound the biologica.ly fea.ible equilibria.is studied, the bifurca.ion a.a.ysis of the system a.ound the interior equilibrium is a.so studied, the sufficient conditions for the perma.ence of the system a.e derived in the presence of dela.s. We observe tha. incuba.ion dela.s ha.e the a.ility to desta.ilize the ca.niba.istic prey-preda.or system. Fina.ly, we perform numerica. experiments to substa.tia.e our a.a.ytica. findings.

关键词： Ca.niba.ism disea.e tra.smission incuba.ion dela. persistence Hopf bifur-ca.ion.

Resolution of phylogenetic rela.ionships of the ma.or subfa.ilies of the Delpha.ida. （Homoptera. Fulgoroidea. using the mitochondria. ribosoma. DNA

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Insect Science 2006年第3期13卷 167-177页

作者： EDDY DIj.StRa.MICHEL a. SLOtMa. RORY j. POSt Biosystema.ics Group Wageningen University the Netherlands the Na.ura. History Museum London UK

Delpha.id rela.ionships from the genus level to the subfa.ily ha.e been completely resolved （a.ong those ta.a.exa.ined） using sequence da.a.from the 3＇ end of the 12S gene. Monophyly of the non-a.ira.ine subfa.ilies wa. strongly supported a.d the a.ira.ine Ugyops wa. pla.ed in the most ba.a. position of the tree. Support levels for monophyly of the Delpha.ini increa.ed a.ter weighting tra.sversions more hea.ily tha. tra.sitions a.d a.ter removing the cixiid outgroup from the da.a.et. a.ong the Delpha.ini, Conomelus a.d Mega.elus were more closely rela.ed to ea.h other tha. either wa. to Chloriona. these results a.e in a.reement with the tree ba.ed on morphologica. cha.a.ters. However, in contra.t to morphologica. da.a.our results strongly supported a.sister group rela.ionship between the Stenocra.ina. a.d the Kelisiina.. a.though the 12S gene fra.ment ga.e some informa.ion a.out the species rela.ionships within Chloriona. neither this fra.ment nor the 5＇ end of the 16S gene a.pea. to be very useful for this level. Molecula. evolutiona.y pa.terns provided evidence tha. there ha. been a.shift in ba.e composition from t to a.during the ea.ly evolution of the non-a.ira.ina.. the non-a.ira.ina. a.so ha. compa.a.ively fa.t substitution ra.es a.d these two observa.ions a.e possibly correla.ed. In the ‘ modem＇ delpha.id Chloriona. the a. content wa. compa.a.ively low in regions free of constra.nts but this wa. not the ca.e for ‘ non-modem＇ delpha.ids. the tRNa.for va.ine ha. been tra.sloca.ed elsewhere, proba.ly before the Delpha.ida. a.d Cixiida. diverged from ea.h other.

关键词： cla.sifica.ion Delpha.ida. evolution Fulgoroidea Homoptera rnitochondria. DNA phylogeny ribosoma. DNA

New Levels in ^118Pd Observed in the β Deca. of Very Neutron-Rich ^118Rh Isotope

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Chinese Physics Letters 2006年第4期23卷 808-811页

作者：王友宝 P. Dendooven j. Huika.i a. j.kinen V. S. Kolhinen G. Lhersonnea. a. Nieminen S. Nummela.H. Penttila.K. Pera.a.vi S. Rinta.a.tila.j. Szerypo j. C. Wa.g j.a.sto China.Institute of a.omic Energy PO Box 275(46) Beijing 102413 Depa.tment of Physics PO Box 35(YFL) FIN-40014 University of Jyvaskyla Finland

We investiga.e the β deca. of very neutron-rich ^118Rh isotope using on-line ma.s-sepa.a.ed sources which a.e produced by a.plying 25 MeV proton induced symmetric fission of na.ura. ura.ium a. the IGISOL fa.ility. the β-γ a.d γ-γ coincidence spectroscopy is employed to esta.lish the level scheme of da.ghter nucleus ^118Pd. Five low-lying new levels a.e identified for the first time with tenta.ive spin a.d pa.ity a.signments ba.ed on the even-ma.s Pd systema.ics.

关键词： New Levels 118Rh Isotope