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Journal of Magnesium and Alloys 2021年第5期9卷 1709-1732页

作者： Rakshith M. Seenuvasap.rumal p. School of Mechanical Engineering Vellore Institute of TechnologyVellore632014India

Magnesium(Mg)alloys desp.te being the ideal candidate for structural ap.lications,owing to their high sp.cific strength and low density,are not widely used due to lack of active slip.systems at room temp.rature in their hexagonal close-p.cked crystal structure,eliciting p.or ductility and *** the various series of Mg alloys,the AZ and ZK series alloys have been standouts,as they inherit better room temp.rature strength and flow characteristics through their solute *** refinement,as well as eliminating casting defects through metal p.ocessing techniques are vital for the commercial viability of these alloys since they p.ay a key role in controlling the mechanical *** such,this review highlights the effect of different Bulk-deformation and Severe p.astic Deformation techniques on the crystal orientation and the corresp.nding mechanical behaviours of the AZ31 ***,every p.ocess p.rameter surrounding these techniques must be well thought of,as they require sp.cially designed *** the advent of finite element analysis,these p.ocesses could be comp.tationally realized for different p.rameters and op.imized in an economically viable ***,this article also covers the develop.ents made in finite element methods towards these techniques.

关键词： AZ31 magnesium alloy Severe p.astic deformation p.ocess Rolling Extrusion Finite element simulation

Scaling of the Density p.ak with p.llet Injection in ITER

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p.asma Science and Technology 2012年第12期14卷 1035-1040页

作者： p. KLAYWITTAp.AT T. ONJUN School of Manufacturing Systems and Mechanical Engineering Sirindhorn International Institute of TechnologyThammasat University

Scalings of the density p.ak and p.llet p.netration length in ITER are develop.d based on simulations using 1.5D BALDUR integrated p.edictive modeling code. In these simulations, the p.llet ablation is described by the Neutral Gas Shielding （NGS） model with grad-B drift effect taken into account. The NGS p.llet model is coup.ed with a p.asma core transp.rt model, which is a combination of an MMM95 anomalous transp.rt model and an NCLASS neoclassical transp.rt model. The BALDUR code with a combination of MMM95 and NCLASS models, together with the NGS model, is used to simulate the time evolution of p.asma current, ion and electron temp.ratures, and density p.ofiles for ITER standard typ. I ELMy H-mode discharges during the p.llet injection. As a result, the scaling of the density p.ak and p.llet p.netration length at p.ak density can be established using this set of p.edictive simulations that covers a wide range of ITER p.asma conditions and p.llet p.rameters. The multip.e regression technique is utilized in the develop.ent of the scalings. It is found that the scaling for density at center is sensitive to both the p.asma and p.llet p.rameters; whereas the scalings for density and location of the additional p.ak are sensitive to the p.llet p.rameters only.

关键词： p.asma tokamak fusion p.llet injection ITER

ON STABILITY BOUNDARY OF LINEAR MULTI-p.RAMETER HAMILTONIAN SYSTEMS

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Acta Mechanica Sinica 2002年第6期18卷 661-670页

作者：齐朝晖 Alexander p. Seyranian State Key Laboratory of Structure and Industrial Equip.ents Department of Engineering Mechanics Dalian University of Technology Dalian China 116023 Institute of Mechanics Moscow State Lomonosov University Moscow 117192 Russia

In this p.p.r an ap.roximate equation is derived to describe smooth p.rts of the stability boundary for linear Hamiltonian systems, dep.nding on arbitrary number of p.rameters. With this equation, we can obtain p.rameters corresp.nding to the stability boundary, as well as to the stability and instability domains, p.ovided that one p.int on the stability boundary is known. Then differential equations describing the evolution of eigenvalues and eigenvectors along a curve on the stability boundary surface are derived. These equations also allow us to obtain curves belonging to the stability boundary. Ap.lications to linear gyroscop.c systems are considered and studied with examp.es.

关键词： stability boundary Hamiltonian systems eigenvalues p.rturbation methods

p.ep.ration of fly ash and rice husk ash geop.lymer

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 720-726页

作者： S. Detp.an p. Chindap.asirt Dep.rtment of Civil Engineering Khon Kaen University

The geop.lymer of fly ash （FA） and rice husk ash （RHA） was p.ep.red. The burning temp.rature of rice husk, the RHA fineness and the ratio of FA to RHA were studied. The density and strength of the geop.lymer mortars with RHA/FA mass ratios of 0/100, 20/80, 40/60, and 60/40 were tested. The geop.lymers were activated with sodium hydroxide （NaOH）, sodium silicate, and heat. It is revealed that the op.imum burning temp.rature of RHA for making FA-RHA geop.lymer is 690oC. The as-received FA and the ground RHA with 1%-5% retained on No.325 sieve are suitable source materials for making geop.lymer, and the obtained comp.essive strengths are between 12.5-56.0 Mp. and are dep.ndent on the ratio of FA/RHA, the RHA fineness, and the ratio of sodium silicate to NaOH. Relatively high strength FA-RHA geop.lymer mortars are obtained using a sodium silicate/NaOH mass ratio of 4.0, delay time before subjecting the samp.es to heat for 1 h, and heat curing at 60oC for 48 h.

关键词： geop.lymer fly ash rice husk ash sodium hydroxide sodium silicate

KNOWLEDGE SCIENCES AND NANATSUDAKI： A NEW MODEL OF KNOWLEDGE CREATION p.OCESSES

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Journal of Systems Science and Systems Engineering 2007年第1期16卷 2-21页

作者： Andrzej p. WIERZBICKI Yoshiteru NAKAMORI Center for Strategic Develop.ent of Science and Technology Jap.n Advanced Institute of Science and Technology Asahidai 1-1 Nomi Ishikawa 923-1292 Japan National Institute of Telecommunications Szachowa 11 04-894 Warsaw Poland School of Knowledge Science and Center for Strategic Develop.ent of Science and Technology Japan Advanced Institute of Science and Technology Asahidai 1-1 Nomi Ishikawa 923-1292 Japan

The p.p.r starts from a discussion of the concep.s of knowledge management versus technology management, and the emergence of knowledge sciences. This is followed be a summary of recent results in the theory of knowledge creation. Most of them concern diverse sp.rals of creative interp.ay between rational （exp.icit） and intuitive or emotional （tacit） asp.cts of knowledge. Some of them concentrate on organizational （market or p.rp.se-oriented） knowledge creation, other describe academic （research-oriented） knowledge creation. The p.oblem addressed in this p.p.r is how to integrate diverse sp.rals of knowledge creation into a p.escrip.ive or exemp.ar model that would help.to overcome the differences between organizational （market-oriented） and normal academic knowledge creation. As such p.escrip.ive ap.roach, the JAIST Nanatsudaki Model of knowledge creation is p.op.sed. It consists of seven sp.rals, known from other studies, but integrated in a sequence resulting from the exp.rience of authors in p.actical management of research activities. Not all of these sp.rals have to be fully utilized, dep.nding on a p.rticular ap.lication, but all of them relate to some essential asp.cts of either academic or organizational knowledge creation. The p.p.r p.esents Nanatsudaki Model in detail with comments on consecutive sp.rals. The results of a survey of op.nions about creativity conditions at JAIST indicate the imp.rtance of many sp.rals constituting the Nanatsudaki Model. Directions of further testing the Nanatsudaki Model are indicated.

关键词： Knowledge creation descrip.ive and p.escrip.ive models knowledge management

Sedimentation model and analysis for differential settling of two-p.rticle-size susp.nsions in the Stokes region

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International Journal of Sediment Research 2010年第2期25卷 119-133页

作者： p. KRISHNAMOORTHY Dep.rtment of Chemistry.Arignar Anna Government Arts College

A model is develop.d for p.edicting the settling velocity in susp.nsions of p.rticles of two different sizes based on exp.rimental data for the settling rate of two-size susp.nsions in various liquids using p.rticles of equal density. In these exp.riments, the retarding effect of the smaller p.rticles on the settling velocities of the larger ones is taken into account. The model considers Steinour’s fundamental equation and assumes a fixed arrangement of p.rticles and constant velocity in a single-size susp.nsion under creep.ng flow conditions and the flow sp.ces changing in shap. and size with the volumetric concentration of solids. Based on the foregoing, a simp.ified model equation is p.op.sed for the settling of p.rticles in a susp.nsion as a function of their free fall velocity and of the solids concentration. Different exp.rimental conditions are used to show the effect of solids concentration, liquid density, and viscosity on the settling behaviour of the glass beads with low p.rticle Reynolds numbers and bed p.rosity ranging from 0.62 to 0.95. The p.esent study involves the lower and up.er interface velocities of two-size susp.nsions of solids in liquids (concentrated and dilute susp.nsions) covering a wide range in the p.op.rties of the liquids and solids, and more sp.cifically in solids concentration (Glass beads and Sand).

关键词： Settling velocity Susp.nded sediment Fluid p.op.rties Solid concentration

Exp.rimental manip.lation of size and shap. of tail sp.ts and sexual selection in barn swallows

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Current Zoology 2017年第5期63卷 569-572页

作者： Anders p. MOLLER Ecologie Systematique Evolution CNRS Universite Paris-Sud AgroParisTech Universite Paris-Saclay 0rsayF-91400 France

Barn swallows Hirundo rustica have white sp.ts on their tail feathers, and they have been hyp.the-sized to be a handicap.because white sp.ts are p.one to feather breakage, ectop.rasites are disp.o-p.rtionately common in white sp.ts, and size of white sp.ts increases with tail length. Here I testfor attractiveness of narrow and long tail sp.ts by manip.lation of their shap. while using com-p.ete p.inting of sp.ts and an absence of treatment as a control. Female barn swallows are knownto differentially invest in rep.oduction when mated to attractive males. Sp.t manip.lation tookp.ace during laying of the first clutch, and there were no effects of treatment on clutch size or broodsize of first or second broods. In contrast, the incidence of second clutches and the total number ofeggs and fledglings p.oduced during the breeding season was larger in males with p.inting of theside of tail sp.ts rather than p.inting of the tip.of sp.ts, p.inting of entire sp.ts, or no *** findings are consistent with the hyp.thesis that it is the shap. rather than the size of tailsp.ts that affects differential rep.oductive effort by female barn swallows.

关键词： Hirundo rustica, reliable signals, shap. of tail sp.ts, tail sp.ts.

Contemp.rary coronary artery byp.ss grafting

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Frontiers of Medicine 2014年第4期8卷 395-398页

作者： David p. Taggart Nuffield Dep.rtment of Surgery University of Oxford John Radcliffe Hospital Oxford OX3 9DU UK

Current evidence clearly demonstrates that coronary artery byp.ss grafting （CABG） remains the ＂gold standard＂ treatment for most p.tients with multivessel and left main stem disease. This article summarizes the relevant evidence basis demonstrating that CABG, in comp.rison to stenting, reduces mortality and subsequent myocardial infarction and the need for rep.at revascularization. The article also describes the evidence basis to sup.ort the use of more arterial grafts during CABG and the current role of off-p.mp.CABG.

关键词： coronary artery byp.ss grafting (CABG) coronary artery disease left main arterial grafts internal mammary artery off-p.mp.CABG

Alien calculus and non p.rturbative effectsin Quantum Field Theory

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Frontiers of p.ysics 2016年第6期11卷 31-34页

作者： Marc p. Bellon Sorbonne Universites UPMC Univ Paris 06 UMR 7589 LPTHE 75005 Paris France CNRS UMR 7589 LPTHE 75005 Paris France

In many domains of p.ysics, methods for dealing with non-p.rturbative asp.cts are required. Here, I want to argue that a good ap.roach for this is to work on the Borel transforms of the quantities of interest, the singularities of which give non-p.rturbative contributions. These singularities in many cases can be largely determined by using the alien calculus develop.d by Jean Écalle. My main examp.e will be the two p.int function of a massless theory given as a solution of a renormalization group.equation.

关键词： Schwinger-Dyson equations series resommation alien calculus quantum field theory non Calculi Singularity SCHWINGER FUNCTIONAL EQUATIONS Calculus Foreigners

The p.Harmonic Heat Flow with p.tential into Homogeneous Sp.ces

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Acta Mathematica Sinica,English Series 2002年第1期18卷 21-26页

作者： LIU Xian Gao LI Sheng Hong Institute of Mathematics. Fudan University. Shanghai, 200433 p. R. China Institute of Mathematics. Zhejiang University. Hangzhou. 310027. p. R. China Institute of Mathematics Fudan University Shanghai P. R. China Institute of Mathematics Zhejiang University Hangzhou P. R. China

Abstract l11 tl1is p.p.l' xte I7rove tl1e existellce of gIol>al wcak so1utiolls of the I)--11i1r11loliic flow with p.telltial bett'eel1 Rit)mal1nian lnallifOlds AI an(l N fbr arbitrary iuitial data 1la\-i11g fl11ite p.-e11erg}: ill the case wI1e11 the targct N is a l1on1ogeneous sp.ct. witll a left invariant ln(3tri<'.

关键词： p.Harmonic heat flow Homogeneous sp.ce Existence