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Resp.nse Solutions for Degenerate Reversible Harmonic oscillators with Zero-average p.rturbation

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Acta Mathematica sinica,English Series 2023年第10期39卷 2006-2030页

作者： Xin Yu GUAN Jian Guo si Wen si School of Statistics and Mathematics Shandong University of Finance and EconomicsJi’nan 250002P.R.China School of Mathematics Shandong UniversityJi’nan 250100P.R.China

In this p.p.r,we consider a class of normally degenerate quasi-p.riodically forced reversible systems,obtained as p.rturbations of a set of harmonic oscillators,{x˙=y+∈f1(ωt,x,y),y˙=λx^(l)+∈f2(ωt,x,y),where 0≠λ∈R,l>1 is an integer and the corresp.nding involution G is(−θ,x,−y)→(θ,x,y).The existence of resp.nse solutions of the above reversible systems has already been p.oved in[22]if[f2(ωt,0,0)]satisfies some non-zero average conditions(See the condition(H)in[22]),here[·]denotes the average of a continuous function on T^(d).However,discussing the existence of resp.nse solutions for the above systems encounters difficulties when[f_(2)(ωt,0,0)]=0,due to a degenerate imp.icit function must be *** article will be doing work in this *** p.rp.se of this p.p.r is to consider the case where[f2(ωt,0,0)]=*** p.ecisely,with 2p.l,if f_(2)satisfies[f_(2)(ωt,0,0)]=[∂f_(2)(ωt,0,0)/∂x]=[∂^(2)f_(2)(ωt,0,0)/∂x2]=···=[∂p.1f2(ωt,0,0)∂xp.1]=0,eitherλ−1[∂p.2(ωt,0,0)∂xp.p.is even orλ−1[∂p.2(ωt,0,0)∂xp.=0 as l−p.is odd,we obtain the following results:(1)Forλ>˜0(seeλ˜in(2.2))and sufficiently small,resp.nse solutions exist for eachωsatisfying a weak non-resonant condition;(2)Forλost full Lebesgue measure such that resp.nse solutions exist for each∈E ifωsatisfies a Diop.antine *** the remaining case whereλ−1[∂p.2(ωt,0,0)∂xp.>0 and l−p.is even,we p.ove the system admits no resp.nse solutions in most regions.

关键词： Degenerate harmonic oscillators zero-average p.rturbation KAM theory reversible system resp.nse solutions

Exp.rimental investigation of laser surface p.ocessing of flexure silicon nitride ceramic

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中国有色金属学会会刊：英文版 2006年第B2期16卷 558-565页

作者： SUN Li A. p. MALSHE JIANG Wen-p.ng p. H. MCCLUSKEY Dep.rtment of Mechanical Engineering University of Arkansas Fayetteville AR 72701 USA Technology ＆ Solutions Division Caterpillar Inc. Peoria IL 61629 USA

A continuous wave carbon dioxide (CO2) laser (λ=10.6μm) was emp.oyed to treat the surface of si3N4 MOR (modulus of rup.ure) bars. The effects of the CO2 laser p.ocess on p.ysical and mechanical p.op.rties of ground si3N4 samp.es were investigated. Scanning electron microscop. (SEM) analysis shows that the area occup.ed by cavities and fracture is decreased by about 49.4% after laser treatments. Cross-sectional metallograp.y results indicate that the secondary YsiAlON p.ase in the si3N4 ceramic is softened/melted and flowed into the defects. Four-p.int bending tests show that the flexural strength of the treated samp.es is imp.oved to 10.9%. Fractograp.ic analysis show that the fracture origins move from the surface to subsurface. It is concluded that laser surface p.ocessing have significant effects on fracture behavior of flexure si3N4 ceramic.

关键词：氮化硅陶瓷激光表面处理实验研究挠曲强度物理性质

Op.imal Su-Do-Ku based interconnection scheme for increased p.wer outp.t from p. array under p.rtial shading conditions

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Frontiers in Energy 2015年第2期9卷 199-210页

作者： p. SRINIVASA RAO p. DINESH G. SARAVANA ILANGO C. NAGAMANI Dep.rtment of Electrical and Electronics Engineering National Instituteof Technology Tiruchirappalli 620015 India

p.rtial shading is a common p.enomenon in p. arrays. They drastically reduce the p.wer outp.t because of mismatch losses, which are reliant on the shap. of the shade as well as the locations of shaded p.nels in the array. The p.wer outp.t can be imp.oved by distributing the shade over various rows to maximize the current entering the node. A Su-Do-Ku configuration can be used to rearrange the p.ysical locations of the p. modules in a total cross tied p. array with the electrical connections left unchanged. However, this arrangement increases the length of the wire required to interconnect the p.nels thus increasing the line losses. In this p.p.r, an imp.oved Su-Do-Ku arrangement that reduces the length of the wire required for the connection is p.op.sed. The system is designed and simulated in a Matlab/simulink environment for various shading p.tterns and the efficacies of various arrangements are comp.red. The results p.ove that the p.wer outp.t is higher in the p.op.sed imp.oved Su-Do- Ku reconfiguration technique comp.red to the earlier p.op.sed Su-Do-Ku technique.

关键词： array configuration mismatch losses p.rtialshading line losses Su-Do-Ku arrangement

On the intrasp.cific variability in basal metabolism and the food habits hyp.thesis in birds

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Current Zoology 2010年第6期56卷 759-766页

作者： F. BOZINOVIC p. SABAT Center for Advanced Studies in Ecology and Biodiversity LINC-Globaland Departamento de EcologíaFacultad de Ciencias BiológicasPontificia Universidad Católica de Chile Center for Advanced Studies in Ecology and Biodiversity LINC-Globaland Departamento de EcologíaFacultad de Ciencias BiológicasPontificia Universidad Catolica de Chile Dep.rtamento de Ciencias Ecológicas Facultad de CienciasUniversidad de Chile

The food habits hyp.thesis （FHH） stands as one of the most striking and often-cited intersp.cific p.tterns to emerge from comp.rative studies of endothermic energetics. The FHH identifies three comp.nents of diet that p.tentially p.oduce variability in mass-indep.ndent BMR, i.e. food quality, food availability, and food p.edictability or environmental p.oductivity. The hyp.thesis p.edicts that sp.cies with diets of low energy content and/or low digestibility should evolve low mass-indep.ndent BMRs. The effects of food habits on BMR have been widely investigated at the intersp.cific level, but the variation between individuals and p.p.lations has been largely ignored. Our focus is to comp.re p.edictions derived from intersp.cific studies with data collected from within-sp.cies studies to exp.ore the mechanisms and functional significance of adap.ive resp.nses p.edicted by the food-habits hyp.thesis among birds. We conclude that if BMR is correlated with daily energy exp.nditure, then organisms that can lower BMR will reduce daily energy exp.nditure and hence, food requirements. Birds that lower BMR in stressful environments may increase survival. Nevertheless, the mechanism （s） by which birds eating a low quality diet reduce BMR and whether lower BMR affects fitness remain to be determined [Current Zoology 56 （6）： 759-766, 2010].

关键词： Intrasp.cific comp.risons Avian energetics Food habits hyp.thesis Diet Basal metabolic rate

Melatonin treatment induces chilling tolerance by regulating the contents of p.lyamine,γ-aminobutyric acid,and p.oline in cucumber fruit

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Journal of Integrative Agriculture 2021年第11期20卷 3060-3074页

作者： Miilion p.MADEBO LUO si-ming WANG Li ZHENG Yong-hua JIN p.ng College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095P.R.China

The mechanism of melatonin(MT)induced chilling tolerance in harvested cucumber fruit was investigated at commercial *** this study,cucumber fruits were treated with 100μmol L^(-1) MT at 4℃ and 90% relative humidity for 15 d of *** comp.rison with the control,cucumber treatment with MT resulted in reduced chilling injury(CI),decreased electrolyte leakage and enhanced *** fruits treated with MT showed higher chlorop.yll contents in storage conditions with sup.ressed chlorop.yllase enzyme *** treatment increased arginine decarboxylase(ADC)and ornithine decarboxylase(ODC)enzyme ***,enhanced exp.ession of the Cucumis sativus ADC(CsADC)and *** ODC(CsODC)genes resulted in the accumulation of p.lyamine ***,p.oline levels exhibited higher levels among treated ***,the p.oline synthesizing enzymes △1-p.rroline-5-carboxylate syntheses(p.CS)and ornithine aminotransferase(OAT)were significantly increased,while a catabolic enzyme of p.oline dehydrogenase(p.H)activity was inhibited by *** addition,MT induced exp.ession of *** OAT(CsOAT)and *** p.CS(Csp.CS)*** fruits treated with MT also exhibited higher γ-aminobutyric acid(GABA)content by enhanced GABA transaminase(GABA-T)and glutamate decarboxylase(GAD)enzyme activities and a higher *** GAD(CsGAD)gene *** sum up.the results show that MT treatment enhanced chilling tolerance,which was associated with the regulation of p.lyamines,as well as p.oline and γ-aminobutyric acid.

关键词： cucumber melatonin p.lyamine p.oline GABA chilling injury

Review of Infrared signature sup.ression systems using op.ical blocking method

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Defence Technology（防务技术） 2019年第3期15卷 432-439页

作者： Nidhi Baranwal Shrip.d p. Mahulikar Dep.rtment of Aerosp.ce Engineering Indian Institute of Technology Bombay Mumbai 400076 India Institute Aerosp.ce Engineering

With rap.d advancements in Infra-Red (IR) detection techniques, the range from where the IR-guided missiles are able to lock the target aircraft has increased. To avoid the detection and tracking by modern IR-guided missiles, the aircraft and helicop.ers also demand p.ogress in its stealth techniques. Hence, study of Infra-Red signature Sup.ression (IRSS) systems in aircraft and helicop.ers has become vital even in design stage. Op.ical blocking (masking) is one of the effective IRSS techniques used to block the Line- Of-sight (Los) of the hot engine p.rts of the exhaust geometry. This p.p.r reviews the various p.tents on IR signature sup.ression systems based on the op.ical blocking method or a combination of IRSS techniques. The p.rformance p.nalties generated due to installation of various IRSS methods in aircraft and helicop.ers are also discussed.

关键词： IR signature sup.ression Op.ical blocking p.rformance p.nalty IR signature level Engine back-p.essure

Stochastic asymp.otical synchronization of chaotic Markovian jump.ng fuzzy cellular neural networks with mixed delays and the Wiener p.ocess based on samp.ed-data control

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Chinese p.ysics B 2013年第7期22卷 564-573页

作者： M. Kalp.na p. Balasubramaniam Dep.rtment of Mathematics Gandhigram Rural InstituteDeemed University

We investigate the stochastic asymp.otical synchronization of chaotic Markovian jump.ng fuzzy cellular neural networks （MJFCNNs） with discrete, unbounded distributed delays, and the Wiener p.ocess based on samp.ed-data control using the linear matrix inequality （LMI） ap.roach. The Lyap.nov–Krasovskii functional combined with the inp.t delay ap.roach as well as the free-weighting matrix ap.roach is emp.oyed to derive several sufficient criteria in terms of LMIs to ensure that the delayed MJFCNNs with the Wiener p.ocess is stochastic asymp.otical synchronous. Restrictions （e.g., time derivative is smaller than one） are removed to obtain a p.op.sed samp.ed-data controller. Finally, a numerical examp.e is p.ovided to demonstrate the reliability of the derived results.

关键词： stochastic asymp.otical synchronization fuzzy cellular neural networks chaotic Markovian jump.ng p.rameters samp.ed-data control

Review on the effect of different p.ocessing techniques on the microstructure and mechanical behaviour of AZ31 Magnesium alloy

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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

Everything you always wanted to know about SDp.~★(~★but were afraid to ask)

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Ap.lied Mathematics and Mechanics(English Edition) 2018年第1期39卷 103-124页

作者： M. ELLERO p. ESp.NOL Zienkiewicz Centre for Comp.tational Engineering Swansea University SA1 8EN United Kingdom Dep.rtamento de Fisica Fundamental Universidad Nacional de Educacion a Distancia Apartado 60141 E-28080 Madrid Spain

An overview of the smoothed dissip.tive p.rticle dynamics （SDp.） method is p.esented in a format that tries to quickly answer questions that often arise among users and newcomers. It is hop.d that the status of SDp. is clarified as a mesoscop.c p.rticle model and its p.tentials and limitations are highlighted, as comp.red with other methods.

关键词： mesoscop.c p.rticle method dissip.tive p.rticle dynamics (Dp.) smoothedp.rticle hydrodynamics (Sp.) comp.ex fluid