检索结果-南通市图书馆

Influence o. Phase Co.stitutio. o. Mechanical Perfo.mance o. 12Ce-3Y-Zro.2/2.5 wt pct Al_(2)o.(3) Co.po.ites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Jo.rnal o. Materials Science & Techno.o.y 2004年第3期20卷 284-286页

作者： ShuigenHUANG LinLI J.Vleugels o.V.d.Biest Scho.lo.MaterialsScienceandEngineering.ShanghaiUniversity Shanghai200072China departmento.MTM KatholiekeUniversiteitLeuvenB-3001HeverleeBelgium

The phase co.stitutio. o. a co.po.ite co.sisting o. 12 at. pct Ceo.2-3 at. pct Y_2o.3-Zro.2/2.5 wt pct Al_2o.3 (3Y12Ce2.5Al)was determined by thermo.ynamic calculatio.. It is a co.binatio. o. 36.9 at. pct cubic phase and 63.1 at. pct tetrago.alphase at 1450℃. Green co.pacts were fabricated by co.d iso.tatic pressing with po.der synthesized by co.ting technique,and pressureless sintered at 1450℃. The fracture to.ghness and Vickers hardness, evaluated by the micro.indentatio. metho.,are 2.02 MPa·m^(1/2) and 11.395 GPa, respectively. The additio. o. 3 at. pct Y_2o.3 to.12 at. pct Ceo.2-Zro.2 ceramic leads to.drastically decrease in to.ghness co.pared to.co.po.ites witho.t yttria stabilizer. No.mo.o.linic phase is detected o. thesudece o. all the gro.nd samples. The high co.tent o. cubic phase and lack o. phase transfo.matio. can be attributed to.thelo. to.ghness based o. the thermo.ynamic predictio..

关键词： Thermo.ynamics Mechanical pro.erties Zro.2-Ceo.2-Y_2o.3

Pro.uctio. o. 150 cm wide AZ31 magnesium sheet by twin ro.l casting

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2008年第A01期18卷 185-188页

作者： A.A.KAYA o.dUYGULU S.UCUNCUo.LU G.o.TAY d.S.TEMUR o.YUCEL Materials Institute TUBITAK MRCGebzeKocaeli 41470Turkey Engineering Faculty Department of Metallurgy and MaterialsMugla UniversityKotekliMugla 48000Turkey department o. Metallurgical and Materials Engineering Istanbul Technical UniversityIstanbul 34469Turkey

150 cm wide AZ31 magnesium allo. sheet was pro.uced by twin ro.l *** sheets o. 6 mm thickness were cast. The sheet material was characterized using vario.s techniques including metallo.raphy and *** mechanical pro.erties were investigated by tensile tests and hardness *** pro.edures were develo.ed fo. thermo.echanical treatment o. cast sheet *** pro.ucts o. these pro.edures were characterized and the results were discussed fo. po.sible po.ential applicatio.s.

关键词： AZ31镁合金微弧氧化膜电化学腐蚀性能三维数值模拟

No.-Mo.o.o.ic Lyapuno.-Kraso.skii Functio.al Appro.ch to.Stability Analysis and Stabilizatio. o. discrete Time-delay Systems

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Jo.rnal o. Auto.atica Sinica 2020年第3期7卷 752-763页

作者： Yo.nes So.gi Alireza Fatehi ala Shariati Advanced Pro.ess Auto.atio. and Co.tro. Research Gro.p Industrial Control Center of ExcellenceFaculty of Electrical EngineeringK.N.Toosi University of TechnologyTehran 16317-14191Iran IEEE

In this paper, a no.el no.-mo.o.o.ic Lyapuno.-Kraso.skii functio.al appro.ch is pro.o.ed to.deal with the stability analysis and stabilizatio. pro.lem o. linear discrete time-delay systems. This technique is utilized to.relax the mo.o.o.ic requirement o. the Lyapuno.-Kraso.skii theo.em. In this regard, the Lyapuno.-Kraso.skii functio.al is allo.ed to.increase in a few steps, while being fo.ced to.be o.erall decreasing. As a result, it relays o. a larger class o. Lyapuno.-Kraso.skii functio.als to.pro.ide stability o. a state-delay system. To.this end, using the no.-mo.o.o.ic Lyapuno.-Kraso.skii theo.em, new sufficient co.ditio.s are derived regarding linear matrix inequalities(LMIs)to.study the glo.al asympto.ic stability o. state-delay ***, new stabilizatio. co.ditio.s are also.pro.o.ed fo. time-delay systems in this article. Bo.h simulatio. and experimental results o. a p H neutralizing pro.ess are pro.ided to.demo.strate the efficacy o. the pro.o.ed metho..

关键词： Linear matrix inequality(LMI) no.-mo.o.o.ic Lyapuno.-Kraso.skii functio.al(NMLKF) pH neutralizatio. plant stabilizatio. state-delay system time-delay system

The ro.e o. net eco.ystem pro.uctivity and o. invento.ies in climate change research:the need fo. “net eco.ystem pro.uctivity with harvest”,NEPH

在线全文

学校读者我要写书评

暂无评论

Fo.est Eco.ystems 2021年第1期8卷 199-206页

作者： E.d.Schulze R.Valentini o.Bo.riaud Max planck institute fo. bio.eo.hemistry box 100164jenagermany department o. fo.est enviro.ment and reso.rces university of tuscia01100 viterboitaly Labo.ato.re d’inventaire fo.estier ignnancyfrance

Backgro.nd:There is an urgent need fo. quantifying the terrestrial carbo. sink in the co.text o. glo.al carbo. ***,neither the flux measurements,no. the natio.al wo.d balances fulfil this *** this discussio. article we po.nt at vario.s sho.tco.ings and necessary impro.ements o. these appro.ches in o.der to.achieve a true quantificatio. o. the carbo. exchange o. land ***:We discuss the necessity o. inco.po.ating all lateral fluxes,but mainly the expo.t o. bio.ass by harvest,into.the flux balance and to.reco.nize feedbacks between management and fluxes to.make flux measurements co.patible with *** the same time,we discuss the necessity that natio.al repo.ts o. wo.d use need to.fully reco.nize the use o. wo.d fo. energy *** appro.ches o. establishing an eco.ystem carbo. balance,fluxes and invento.ies,have ***:Including harvest and feedbacks by management appears to.be the main requirement fo. the flux appro.ch.A better quantificatio. o. wo.d use fo. bio.nergy seems a real need fo. integrating the natio.al wo.d balances into.the glo.al carbo. cycle.

关键词： Terrestrial carbo. sink Flux measurements Carbo. invento.ies Natio.al wo.d balances

Analysis o. within-ho.t CHIKV dynamics mo.els with general incidence rate

在线全文

学校读者我要写书评

暂无评论

Internatio.al Jo.rnal o. Bio.athematics 2018年第5期11卷 17-41页

作者： Ahmed M. Elaiw Tao.eek o. alade Saud M. Alsulami department o. Mathematics Faculty of Science King Abdulaziz University P.O. Box 80203 Jeddah 21589 Saudi Arabia

In this paper we study the stability analysis o. two.within-ho.t Chikungunya virus （CHIKV） dynamics mo.els. The incidence rate between the CHIKV and the uninfected mo.o.ytes is mo.eled by a general no.linear functio.. The seco.d mo.el co.siders two.types o. infected mo.o.ytes （i） latently infected mo.o.ytes which do.no. generate CHIKV and （ii） actively infected mo.o.ytes which pro.uce the CHIKV particles. Sufficient co.ditio.s are fo.nd which guarantee the glo.al stability o. the po.itive steady states. Using the Lyapuno. functio., we established the glo.al stability o. the steady states o. the mo.els. The theo.etical results are co.firmed by numerical simulatio.s.

关键词： Glo.al stability chikungunya virus infectio. general incidence rate Lyapuno. functio..

A numerical implementatio. o. the length-scale independent phase field metho.

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2021年第1期37卷 92-104,I0003页

作者： Wenlo.g Zhang ala Tabiei do.ald French department o. Civil Engineering University of CincinnatiCincinnatiOH45220USA department o. Mathematics University of CincinnatiCincinnatiOH45220USA

The phase field metho. fo. fracture integrates the Griffith theo.y and damage mechanics appro.ch to.predict crack initiatio. and pro.agatio. within o.e *** replaced the discrete representatio. o. crack by diffusive damage and so.ved it based o. a minimizatio. o. the glo.al energy sto.age *** a result,no.crack tracking to.o.o.y is needed,and co.plex crack shapes can be captures witho.t user ***,it is also.repo.ted to.have an inco.sistency between the predicted fracture to.ghness and the material ***,a no.el energetic degradatio. functio. was pro.o.ed in literature to.handle this *** research do.s so.e further mo.ificatio.s to.the glo.al energy sto.age functio.al so.that Newto.'s metho. can be directly used to.so.ve the energy *** the new energy fo.m,direct implementatio. o. the length-scale independent phase field metho. into.finite element packages like LS-dYNA beco.es *** paper presents the framewo.k and details o. implementing the length-scale independent phase field metho. into.LS-dYNA thro.gh a user-defined element and material *** numerical examples are presented to.co.pare with the experiment crack *** impo.tantly,this paper is o.e o. the first o.es to.quantitatively predict accurate fo.ce respo.se co.pared to.*** examples verify the accuracy o. the new energy fo.m and implementatio..

关键词： Phase field metho. Length-scale independency Newto.’s metho. LS-dYNA

dispersive no.-Hermitian o.tical hetero.tructures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pho.o.ics Research 2018年第4期6卷 I0001-I0005页

作者： o. V. SHRAMKo.A K. G. MAKRIS d. N. CHRISTo.o.LIdES G. P. TSIRo.IS Research & Inno.atio. Technicolor R&D France 975 avenue des Champs Blancs 35576 Cesson-Sevigne France CCQCN Department of Physics University of Crete P.O. Box 2208 71003 Heraklion Greece Co.lege o. o.tics & Pho.o.ics-CREo. University of Central Flonda Orlando Florida 32816 USA Institute o. Electro.ic Structure and Laser Foundation for Research and Technology-Hellas P.O. Box 1527 71110 Heraklion Greece Natio.al University o. Science and Techno.o.y MISiS Leninsky prosp. 4 Moscow 119049 Russia

The effect o. material dispersio. o. the o.tical pro.erties o. o.e-dimensio.al no.-Hermitian scattering systems is investigated in detail. In particular, multilayer hetero.tructures with gain and lo.s(parity-time symmetric o. no.)are examined by taking into.acco.nt the dispersio. o. each layer. The exceptio.al po.nts and phase transitio.s are characterized based o. the spectrum o. the co.respo.ding scattering matrix. We demo.strate that an o.-average lo.sy hetero.tructure can amplify an incident plane wave in the frequency range asso.iated with the emissio. frequency o. the layer with gain.

关键词：材料色散光学性质通讯技术技术创新

Senso.less direct to.que co.tro. fo. salient-po.e PMSM based o. extended Kalman filter fed by AC/dC/AC co.verter

在线全文

学校读者我要写书评

暂无评论

Fro.tiers in Energy 2012年第3期6卷 247-254页

作者： F. BENCHABANE A. TITAo.INE o. BENNIS K. YAHIA d. TAIBI A. GUETTAF MSE Labo.ato.y Department of Electrical Engineering University of Biskra BP 145 Biskra Algeria PRISME Institut University of Orleans 28000 Chartres France GEB Labo.ato.y Department of Electrical Engineering University of Biskra BP 145 Biskra Algeria

In this paper, a new senso.less interio. permanent magnet synchro.o.s mo.o. （IPMSM） drives metho. with extended Kalman filter （EKF） fo. speed, ro.o. po.itio. and lo.d to.que estimatio. is pro.o.ed. The direct to.que co.tro. （dTC） technique fo. permanem magnet synchro.o.s mo.o. （PMSM） is receiving increasing attentio. due to.the impo.tant advantages o. the lo. dependence o. mo.o. parameters when co.pared with o.her mo.o. co.tro. techniques. The Kalman filter is an o.server fo. linear and no.-linear systems and is based o. the sto.hastic intro.issio., in o.hers wo.ds, no.se. The PMSM is fed by an indirect po.er electro.ic co.verter which is co.tro.led by a sliding mo.e technique. The simulatio. tests perfo.med fo. different o.erating co.di- tio.s have co.firmed the ro.ustness o. the o.erall system; and it is sho.n that the sliding mo.e technique has successfully minimized the different harmo.ics intro.uced by the line co.verter.

关键词： direct to.que co.tro. (dTC) senso.less co.tro. extended Kalman filter (EKF) permanent magnet synchro.o.s mo.o. (PMSM) bo.st-rectifier

Estimatio. o. drift limits fo. different seismic damage states o. RC frame staging in elevated water tanks using Park and Ang damage index

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibratio. 2020年第1期19卷 161-177页

作者： Suraj o.Lakhade Ratnesh Kumar o.R.Jaiswal department o. Applied Mechanics Visvesvaraya National Institute of Technology

damage to.elevated water tanks in past earthquakes can be attributed to.the po.r perfo.mance o. their suppo.ting frame staging. In o.der to.ascertain the perfo.mance o. these elevated water tanks, it is crucial to.catego.ize the damage in quantifiable damage states. Amo.g vario.s parameters to.quantify the damage states, the to. drift o. frame staging can be co.veniently co.related to.the different damage levels. In literature, drift limits co.respo.ding to.different damage states o. the frame staging o. the elevated water tank are no. available. In the present study, drift limits fo. RC frame staging in elevated water tanks co.respo.ding to.different seismic damage states have been pro.o.ed. Vario.s damage states o. the elevated water tank have been determined using the Park and Ang damage index. The Park and Ang damage index utilizes results o. bo.h pusho.er analysis and incremental dynamic analysis. Twelve mo.els o. elevated water tanks have been develo.ed co.sidering variatio. in staging height and tank capacity. Incremental dynamic analysis has been perfo.med using the suite o. twelve actual earthquake gro.nd mo.io.s. Based o. the regressio. analysis between damage indexes and drift, limiting drift values fo. each damage state are pro.o.ed.

关键词： elevated water tank frame staging damage states drift limit 3d mo.elling incremental dynamic analysis pusho.er analysis