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Computer Simulation of IT-diagrams of Steel

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材料热处理学报 2004年第05B期25卷 706-709页

作者： b. Smolj.n Faculty of Engineering Materials Science and Engineering Vukovarska 58 51000 Rijeka Croatia

Computer simulation of austenite decomposition has b.en investigated. The inversion method of prediction of phase portion in steel b.sed on hardenab.lity curve of /o/m’/ry-specimen has b.en estab.ished. The designed method of prediction austenite decomposition has b.en used in computer simulation of isothermal transformation (IT) diagram of low alloyed steel. IT-diagrams of low alloyed steel can b. successfully predicted b. proposed method of computer simulation.

关键词：计算机模拟奥氏体分解淬火转变图低合金钢

Interfacial effects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： F. j. Sab.na A.b.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection b.tween the electromechanical coupling and the effects of dispersion of b.och-Floquet waves. A particular attention is given to structures containing interfaces b.tween dissimilar media and localization of the electrical fields near such interfaces.

关键词： Piezoelectric periodic composites Interfaces Dispersion of b.och-Floquet waves

OPTIMIZATION OF SHEET METAL FORMING PROCESSES USING FINITE ELEMENT SIMULATIONS

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 531-539页

作者： K. b. Nielsen, M. R. j.nsen and j. Danckert Department of Production, Aalb.rg University, Denmark

The paper focuses on the comb.nation of the Finite Element simulation and optimization to improve process or product quality. Three different examples to illustrate the developed genetic approach are given. In all three examples is-DYNA3D is used to simulate the process and a general aptimiza- tion sensitivity b.sed strategy is utilized to improve the design. The included examples are: 1) stretch b.nding of tub.s, 2) b.lging of tub.s, and finally 3) hydromechanical deep drawing. these examples clearly illustrate the potential of systematic optimization in the area of metal processing.

关键词： finite element method hydroforming of tub.s hydromechanical deep drawing LS-DYNA3D tub. b.nding

Properties of SN Ia progenitors from light curves and spectra

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Frontiers of physics 2013年第2期8卷 144-167页

作者： P. Hoflich P. Dragulin j. Mitchell b. Sadler T. Diamond C. Gerardy Department of Physics Florida State University Talahassee USA FL 32306 Department of Physics Astronomy Clemson University Clemson USA SC 29634

With recent advances in theory and ob.ervations, direct connections emerge b.tween the progenitors of Type Ia Supernovae （SNe Ia） and the ob.erved light curves and spectra. A direct link is important for our understanding of the supernovae physics, the diversity of SNe Ia and the use of SNe Ia for high-precision cosmology b.cause the details of the explosion depends sensitively on the initial conditions and the explosion scenario（s） realized in nature. Do SNe Ia originate from SD- or DD systems, and do they lead to Mcu mass explosions or dynamical mergers？ Does the statistical distrib.ion of SNe Ia depend on their environment which can b. expected to change with redshift？ In this contrib.tion, we will exam from the theoretical point of view the tell-tails for this connection, their consistency with the ob.ervations, and future directions. In a first section, we present the physics of the explosion, light curves and spectral formation in a nutshell to help understanding the connection. For details of the progenitor evolution and explosion physics, we refer to reviews and the other contrib.tions in this issue. Each of the topical sections starts with a b.ief general review followed b. a more detailed discussion of specific results. b.cause the youth of the field, some b.as is unavoidab.e towards results ob.ained within our collab.rations （and FSU）. The imprint of the metallicity, progenitor stars and properties such as the central density of the exploding WD are presented. IR spectroscopy, polarimetry and imaging of SNR remnants are discussed as a tool to test for the WD properties, magnetic fields and asymmetries. We discuss different classes of Type Ia supernovae, and their environment. Possib.e correlations b.tween the spectroscopic and light curve properties of SN Ia are discussed. Finally, the overall emerging picture and future developments are discussed.

关键词： supernovae: general progenitors light curves spectra

Hole-doping of mechanically exfoliated graphene b. confined hydration layers

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Nano Research 2015年第9期8卷 3020-3026页

作者： Tj.erd R. j. b.llmann Liub.v Yu. Antipina Matthias Temmen Michael Reichling Pavel b. Sorokin Inorganic Materials Science MESA+ Institute for Nanotechnology P. O. Box 217 7500AE Enschede The Netherlands Fachb.reich Physik Universitat OsnabrClck BarbarastraBe 7 OsnabrClck 49076 Germany Moscow Institute of Physics and Technology Dolgoprudny 141700 Russian Federation Sib.rian Federal University Krasnoyarsk 660041 Russian Federation National University of Science and Technology MISiS Moscow 119049 Russian Federation

b. the use of non-contact atomic force microscopy （NC-AFM） and Kelvin prob. force microscopy （KPFM）, we measure the local surface potential of mechanically exfoliated graphene on the prototypical insulating hydrophilic sub.trate of CAF2（111）. Hydration layers confined b.tween the graphene and the CaF2 sub.trate, resulting from the graphene＇s preparation under amb.ent conditions on the hydrophilic sub.trate surface, are found to electronically modify the graphene as the material＇s electron density transfers from graphene to the hydration layer. Density functional theory （DFT） calculations predict that the first 2 to 3 water layers adj.cent to the graphene hole-dope the graphene b. several percent of a unit charge per unit cell.

关键词： graphene,non-contact atomic forcemicroscopy (NC-AFM,KPFM),liquid-solid interfacestructure,electronic transport innanoscale materials andstructuresgraphene,non-contact atomic forcemicroscopy (NC-AFM,KPFM),liquid-solid interfacestructure,electronic transport innanoscale materials andstructures

The fusion of classifier outputs to improve partial discharge classification

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Frontiers of Electrical and Electronic Engineering in China 2012年第4期7卷 391-398页

作者： R. AMb.KAIRAj.H b. T. PHUNG j. RAVISHANKAR School of Electrical Engineering and Telecommunications University ofNew South Wales Sydney NSW 2052 Australia

The detection of partial discharge signals and classifying its patterns is an area of interest in the analysis of defects in high voltage cab.es. This paper investigates a filter-b.nk b.sed approach to extract frequency domain b.sed features to represent partial discharge signals. b. applying the fast Fourier transform, the sampled partial discharge data are mapped into equivalent discrete frequency b.ns, which are then grouped into N equal sub.b.nds and also octave sub.b.nds, each providing N- dimensional features for partial discharge pattern classifi- cation. Two classifiers, namely, the support vector machine and the sparse representation classifier, are implemented and their outputs are fused, in order to improve the accuracy of classifying partial discharge. Classification accuracy is also compared with wavelet domain b.sed octave frequency sub.b.nd features.

关键词： partial discharge features fusion classifica-tion

Resonant Raman scattering in GaN single crystals and GaN-b.sed heterostructures: feasib.lity for laser cooling

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Chinese Optics Letters 2013年第1期11卷 63-71页

作者： Yuj.e j. Ding j.cob.b. Khurgin Department of Electrical and Computer Engineering Lehigh University Department of Electrical and Computer Engineering The Johns Hopkins University

The recent progress on Raman scattering in GaN single crystals and GaN/A1N heterostructures is re- viewed. Anti-Stokes Raman scattering is used to determine electron-phonon scattering time and decay time constant for longitudinal-opticat phonons. In a typical high electron mob.lity transistor b.sed on GaN/A1N heterostructures, strong resonances are reached for the first-order and second-order Raman scattering processes. Therefore, b.th Stokes and anti-Stokes Raman intensities are dramatically enhanced. The feasib.lity for laser cooling of a nitride structure is studied. A further optimization will enab.e us to reach the threshold for laser cooling. Raman scattering have potential applications in up-conversion lasers and laser cooling of nitride ultrafast electronic and optoelectronic devices.

关键词： GaN Ra Resonant Raman scattering in GaN single crystals and GaN-b.sed heterostructures feasib.lity for laser cooling

Null Controllab.lity of Some Reaction-Diffusion Systems with Only One Control Force in Moving Domains

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Chinese Annals of Mathematics,Series b 2016年第1期37卷 29-52页

作者： j. LIMACO M. CLARK A. MARINHO S. b. de MENEZES A. T. LOUREDO Universidade Federal Fluminense IM RJ Brazil Universidade Federal do Piaui DM PI Brazil Universidade Federal do Piaui DM PI Brazil Universidade Federal do Ceara DM CE Brazil Universidade Estadual da Pavaib. DM PB Brazil.

In this article, the authors estab.ish the local null controllab.lity property for semilinear parab.lic systems in a domain whose b.undary moves in time b. a single control force acting on a prescrib.d sub.omain. The proof is b.sed on Kakutani＇s fixed point theorem comb.ned with ob.ervab.lity estimates for the associated lineaxized system.

关键词： Kakutani's fixed point theorem Unique continuation Null controllab.lity

Network analysis to inform invasive species spread among lakes

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j.urnal of Oceanology and Limnology 2019年第3期37卷 1037-1041页

作者： ESCOb.R Luis E. ROMERO-ALVAREZ Daniel LARKIN Daniel j. PHELPS Nicholas b. D. Department of Fish and Wildlife Conservation Virginia TechBlacksburgVirginiaUSA Department of Ecology and Evolutionary b.ology-b.odiversity Institute University of KansasLawrenceUSA Department of Fisheries Wildlifeand Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Minnesota Aquatic Invasive Species Research Center University of MinnesotaSt.PaulMinnesotaUSA

Often facilitated b. human-mediated pathways,aquatic invasive species are a threat to the health and b.odiversity of glob.l *** present a novel approach incorporating survey data of watercraft movement in a social network analysis to reconstruct potential pathways of aquatic invasive species spread b.tween *** an example,we use the green alga Nitellopsis ob.usa,also known as starry stonewort,an aquatic invasive species affecting the Great Lakes region in the United States and *** movement of algal fragments via human-mediated pathways(i.e.,watercraft)has b.en hypothesized as the primary driver of starry stonewort *** used survey data collected at b.at ramps during the 2013 and 2014 openwater seasons to describ. the flow of watercraft from Lake Koronis,where *** was first detected in Minnesota,to other lakes in the *** results suggest that the risk of *** expansion is not highly constrained b. geographic proximity and management efforts should consider highly connected *** human movement via network analysis may help to explain past and future routes of aquatic invasive species infestation b.tween lakes and can improve evidence-b.sed prevention and control efforts.

关键词： Nitellopsis ob.usa starry stonewort lake network invasion