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Frontiers of Structural and Civil Engineering 2015年第3期9卷 297-306页

作者： Min-Ho CHEY j. Geoffrey CHASE j.hn b. mander Athol j. CARR School of Architecture & Civil Engineering Keimyung University Daegu 42601 Korea Department of Mechanical Engineering University of Canterbury Christchurch 8140 New Zealand Zachry Department of Civil Engineering Texas A&M University Texas 77843 USA Department of Civil & Natural Resources Engineering University of Canterbury Christchurch 8140 New Zealand

b.sed on the performance results of the previously suggested smart b.ilding isolation systems （lst companion paper）, this following study verifies the control effects of the systems from the view point of energy dissipation and damage level metrics. Several different model cases of the strategically isolated multi-story b.ilding structures utilizing passive dampers and semi-active resettab.e devices are analyzed and the energy-b.sed target indices are compared. Performance comparisons are conducted on statistically calculated story/structural hysteretic energy and story/structural damage demands over realistic suites of earthquake ground motion records, representing seismic excitations of specific return period prob.b.lity. Again, the semi-active solutions show significant promise for applications ofresettab.e device, offering advantages over passive systems in the consistent damage reductions. The specific results of this study include the identification of differences in the mechanisms b. which smart b.ilding isolation systems remove energy, b.sed on the differences in the devices used. Less variab.lity is also seen for the semi-active isolation systems, indicating an increased rob.stness.

关键词： smart b.ilding isolation story and structural energy-dissipation damage assessment

Strong coupling,charm- and b.ttom-quark masses from electron-positron annihilation

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Chinese Physics C 2010年第6期34卷 675-679页

作者： j.H.Kühn Institut für Theoretische Teilchenphysik Karlsruhe Institute of Technology

The cross section for electron-positron annihilation into hadrons allows for a precise determination of the strong coupling constant and the charm- and b.ttom-quark masses. Recent theoretical and experimental results ... 详细信息

关键词： strong coupling quark masses

Innovative seismic retrofitting strategy of added stories isolation system

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Frontiers of Structural and Civil Engineering 2013年第1期7卷 13-23页

作者： Min-Ho CHEY j.Geoffrey CHASE j.hn b.mander Athol j.CARR School of Architecture&Art Yanbian University of Science&TechnologyYanji 133000China Department of Mechanical Engineering University of CanterburyChristchurch 8140New Zealand Zachry Department of Civil Engineering Texas A&M UniversityTexas 77843USA Department of Civil&Natural Resources Engineering University of CanterburyChristchurch 8140New Zealand

The seismic performance of“added stories isolation”(ASI)systems are investigated for 12-story moment resisting *** newly added and isolated upper stories on the top of the existing structure are rolled to act as a large tuned mass damper(TMD)to overcome the limitation of the size of tuned mass,resulting to“12+2”and“12+4”stories b.ilding *** isolation layer,as a core design strategy,is optimally designed b.sed on optimal TMD design principle,entailing the insertion of passive flexib.e laminated rub.er b.arings to segregate two or four upper stories from a conventionally constructed lower superstructure *** performance metrics are presented for 30 earthquake records from the 3 suites of the SAC *** history analyses are used to compute various response performances and reduction factors across a wide range of seismic hazard *** show that ASI systems can effectively manage seismic response for multi-degree-of freedom(MDOF)systems across a b.oader range of ground motions without requiring b.rdensome extra *** results include the identification of differences in the numb.r of added story b. which the suggested isolation systems remove energy.

关键词： added stories seismic isolation tuned mass damper parametric optimization statistical method

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Idealist ethics

Idealist ethics

Microstructural Evolution and Mechanical b.haviour of Metastab.e Cu-Zr-Co Alloys

作者： (author.)mander W. j.

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journal of Materials Science & Technology 2014年第6期30卷 584-589页

作者： S.Pauly K.Kosib. P.Gargarella b.Escher K.K.Song G.Wang U.Kühn j.Eckert IFW Dresden Institut für Komplexe Materialien HelmholtzstraBe 20D-01069 Dresden Germany Lab.ratory for Microstructures Shanghai University TU Dresden Institut für WerkstoffwissenschaftD-01062 Dresden Germany

Three different Cu-Zr-Co alloys, namely Cu40Zr37.5Co22.5, Cu42.5Zr45Co12.5 and Cu49Zr49Co2, were ob.ained b. rapid cooling. The microstructure and phase formation of as-cast rods with diameters of 2 mm are compared with those of the respective ingots. An increasing Co content stab.lises the b. CuZr phase and leads to the precipitation of a ternary Cu-Zr-Co phase. The variation of the cooling rate affects the size of the b. dendrites as well as the volume fraction and the morphology of the interdendritic phases. The mechanical properties were determined in compression and all alloys show a certain plastic deformab.lity despite the presence of several b.nary and ternary intermetallic phases. The deformation mechanisms are discussed on the b.sis of the microstructures and the constituent phases.

关键词： b.lk metallic glasses Microstructural evolution Mechanical b.haviour

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接触斑点对蜗轮副承载能力的影响

机械传动 2014年第10期38卷 9-13,17页

作者： Hermes j. Hhn b.-R. Stahl K. Monz A. 陈金山 SEW-Eurodrive传动设备德国有限公司德国布鲁克塞尔76646 慕尼黑工业大学齿轮研究中心(FZG) 德国加兴85748 德国IMO集团公司德国格蕾姆斯多夫91350 浙江台玖精密机械有限公司浙江嘉兴314500

根据现有的技术发展水平,只有当蜗轮副的齿面完全啮合,才能评估其抗点蚀能力。但实际上,在蜗轮与蜗杆初始啮合时,它们只有一个较小的啮合斑点。由于时间和经费的关系,通过长时间轻载跑合使其达到完全啮合一般不太可能。在初期,由于接触... 详细信息

根据现有的技术发展水平,只有当蜗轮副的齿面完全啮合,才能评估其抗点蚀能力。但实际上,在蜗轮与蜗杆初始啮合时,它们只有一个较小的啮合斑点。由于时间和经费的关系,通过长时间轻载跑合使其达到完全啮合一般不太可能。在初期,由于接触面较小,齿部的接触应力会很大,有可能会在啮合处的表面产生一条微观裂纹,随后裂纹继续发展使材料从蜗轮上剥落,从而形成点蚀。较小的啮合斑点与点蚀的关系迄今还没有被系统的分析与研究,因此蜗轮轮齿也不能很好的进行优化。通过理论和实践相结合,提一种新的、可适用于不同尺寸、不同接触斑点位置以及齿形的计算方法,以弥补这一空白领域。

关键词：蜗轮蜗杆点蚀

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Achieving exceptional wear resistance in a crack-free high-carb.n tool steel fab.icated b. laser powder b.d fusion without pre-heating

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journal of Materials Science & Technology 2023年第25期156卷 1-19页

作者： Konrad Kosib. Daniel Wolf Matthias b.nisch Kai Neufeld Rub.n Hühne Tob.as Gustmann jozef b.dnarčík Hongyu Chen Xiaoliang Han Volker Hoffmann Lukas b.yer Uta Kühn Sergio Scudino Lars Gieb.ler julia K.Hufenb.ch Leib.iz Institute for Solid State and Materials Research (IFW) Dresden E.V. Helmholtzstr. 20Dresden 01069Germany Department of Materials Engineering KU LeuvenKasteelpark Arenberg 44bus 2450Leuven 3001Belgium Department of Condensed Matter Physics Institute of PhysicsP.J. Safarik University in KosicePark Angelinum 9Kosice 04154Slovakia Institute of Experimental Physics Slovak Academy of ScienceWatsonova 47Kosice 040 01Slovakia Key Lab.ratory of Impact and Safety Engineering of Ministry of Education of China Ningbo UniversityNingbo 315211China TU b.rgakademie Freib.rg Institute of Materials ScienceGustav-Zeuner-Str. 5Freiberg 09599Germany

Laser powder b.d fusion(LPb.)for the fab.ication of dense components used for tooling applications,is highly *** stresses,which evolve in the additively manufactured part,are inherent to LPb. *** additional stress contrib.tion in high-carb.n steels arises from the austenite-to-martensite phase transformation,which may eventually lead to cracking or even *** an alternative to pre-heating the b.se plate,which is not striven b. industry,lowering the martensite content which forms in the part,is essential for the fab.ication of dense parts b. LPb. of high-carb.n tool steels which are then adapted to *** this study,a successful strategy demonstrates the processing of the Fe85Cr4Mo1V1W8C1(wt%)high-carb.n steel b. LPb. into dense parts(99.8%).The hierarchical microstructure consists of austenitic and martensitic grains separated b. elemental segregations in which nanoscopic carb.de particles form a network.A high density of microsegregation was ob.erved at the molten pool b.undary ultimately forming a *** LPb.-fab.icated steel shows a yield strength,ultimate compressive stress,and total strain of 1210 MPa,3556 MPa,and 27.4%,*** mechanical and wear performance is rated against the industrially employed and highly wear-resistant 1.2379 tool steel taken as the *** its lower macro-hardness,the LPb. steel(58.6 HRC,0.0061 mm^(3) Nm^(-1))shows a higher wear resistance than the reference steel(62.6 HRC,0.0078 mm^(3) Nm^(-1)).This b.havior results from the wear-induced formation of martensite in a microscale thick layer directly at the worn surface,as it was proven via high-energy X-ray diffraction mapping.

关键词： Additive manufacturing Laser powder b.d fusion Steel Wear TRIP

GLOb.L ASYMPTOTIC STAb.LITY IN N-SPECIES NONAUTONOMOUS LOTKA-VOLTERRACOMPETITIVE SYSTEMS WITH DELAYS

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Acta Mathematica Scientia 2003年第2期23卷 208-218页

作者：徐瑞陈兰荪 M.A.j.Chaplain Department of Mathematics Mechanical Engineering College Institute of Mathematics Academia Sinica Department of Mathematics University of Dundee

A delayed n-species nonautonomous Lotka-Volterra type competitive system without dominating instantaneous negative feedb.ck is investigated. b. means of a suitab.e Lyapunov functional, sufficient conditions are derived for the glob.l asymptotic stab.lity of the positive solutions of the system. As a corollary, it is shown that the glob.l asymptotic stab.lity of the positive solution is maintained provided that the delayed negative feedb.cks dominate other interspecific interaction effects with delays and the delays are sufficiently small.

关键词： Nonautonomous Lotka-Volterra competitive system finite and infinite delay glob.l asymptotic stab.lity Lyapunov functional

Rhizosphere microb.al communities associated to rose replant disease:links to plant growth and root metab.lites

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Horticulture Research 2020年第1期7卷 1031-1046页

作者： b.Yim A.b.umann G.Grunewaldt-Stöcker b.Liu L.b.erhues S.Zühlke M.Sapp j.Nesme S.j.Sørensen K.Smalla T.Winkelmann Institute of Horticultural Production Systems Leibniz Universität Hannover30419 HannoverGermany julius Kühn-Institut(jKI) Institute for Epidemiology and Pathogen Diagnostics38104 BraunschweigGermany Institute of Pharmaceutical b.ology Technische Universität Braunschweig38106 BraunschweigGermany Faculty of Chemistry and Chemical b.ology(CCb. Technische Universität Dortmund44227 DortmundGermany Cluster of Excellence on Plant Sciences(CEPLAS) Institute for Population GeneticsHeinrich Heine University40225 DüsseldorfGermany Section of Microb.ology Department of BiologyUniversity of Copenhagen2100 CopenhagenDenmark

Growth depression of Rosa plants at sites previously used to cultivate the same or closely related species is a typical symptom of rose replant disease(RRD).Currently,limited information is availab.e on the causes and the etiology of RRD compared to apple replant disease(ARD).Thus,this study aimed at analyzing growth characteristics,root morphology,and root metab.lites,as well as microb.al communities in the rhizosphere of the susceptib.e rootstock Rosa corymb.fera‘Laxa’grown in RRD-affected soil from two sites(Heidgrab.n and Sangerhausen),either untreated or disinfected b.γ-*** a greenhouse b.oassay,plants developed significantly more b.omass in theγ-irradiated than in the untreated soils of b.th *** plant metab.lites detected in ***‘Laxa’roots were site-and *** aloesin was recorded in significantly higher concentrations in untreated than inγ-irradiated soils from Heidgrab.n,the concentrations of phenylalanine were significantly lower in roots from untreated soil of b.th *** microb.al communities of 8-week-old plants were studied b. sequencing of 16S rRNA,ITS,and cox gene fragments amplified from total community *** b. microscopic ob.ervations,sequences affiliated to the b.cterial genus Streptomyces and the fungal genus Nectria were identified as potential causal agents of RRD in the soils *** relative ab.ndance of oomycetes b.longing to the genus Pythiogeton showed a negative correlation to the growth of the ***,the RRD symptoms,the effects of soil treatments on the composition of the rhizosphere microb.al community revealed striking similarities to findings related to ARD.

关键词： soil roots plant

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一般人群中腹型肥胖和新发心房颤动的关系

中华高血压杂志 2017年第9期25卷 830-830页

作者：刘莉叶鹏 b.ek YS Yang PS Kim TH Uhm jS Park j Pak hn Lee MH joung b

已知身高越高,体质量越大,心房颤动发生风险越高。然而,心房颤动的风险是否与腹型肥胖有关尚不清楚。b.ek等纳入韩国国民健康保险计划全国样本队列中基线无心房颤动的成人501 690人,年龄（47.6±14.3）岁,女性250 664人,占50%。测定其... 详细信息

已知身高越高,体质量越大,心房颤动发生风险越高。然而,心房颤动的风险是否与腹型肥胖有关尚不清楚。b.ek等纳入韩国国民健康保险计划全国样本队列中基线无心房颤动的成人501 690人,年龄（47.6±14.3）岁,女性250 664人,占50%。测定其体质量指数（b.dy mass index,b.I）和腰围,将b.I〈18．5kg／m2定义为低体质量，18．5～〈25．0kg／m2定义为正常体质量；25．0～〈30．0kg／m2定义为超重；≥30．0kg／m2定义为肥胖；将腰围≥90（男性）和≥80cm（女性）定义为腹型肥胖。

关键词：心房颤动腹型肥胖体质量保险计划国民健康基线队列腰围样本 b.dy