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s.mulation Architecture for Modelling Interaction Between Us.r and Elbow-articulated Exos.eleton

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j.urnal of Bionic Engineering 2017年第4期14卷 706-715页

作者： Bas.j. de Kruif Emilio s.hmidhaus.r Konrad s. s.adler Leonard W. O's.llivan s.hool of Des.gn & Health Res.arch Ins.itute University of Limerick Limerick Ireland Netherlands.Organis.tion for Applied s.ientific Res.arch Equipment for Additive Manufacturing 5600 HE Eindhoven The Netherlands Zurich Univers.ty of Applied s.iences School of Engineering 8401 CH Winterthur Switzerland

The aim of our work is.to improve the exis.ing us.r-exos.eleton models.by introducing a s.mulation architecture that can s.mulate its.dynamic interaction, thereby altering the initial motion of the us.r. A s.mulation architecture is.developed that us.s.the mus.ulos.eletal models.from Opens.m, and that implements.an exos.eleton control algorithm and human res.ons. model in Matlab. The mus.ulos.eletal models.need to be extended with the res.ons. of a us.r to external forces.to s.mulate the dy- namic interaction. A s.t of experiments.was.performed to fit this.res.ons. model. A validation tes. s.owed that more than 80% of the variance of the motion could be explained. With the human res.ons. model in the combined s.mulation architecture, a s.mulation in which an obj.ct connects.with the exos.eleton or with the human is.performed. The effect of the exos.eleton on, among others. mus.le excitation and altered motion can be as.es.ed with this.architecture. Our work can be us.d to better predict the effect an exos.eleton has.on the us.r.

关键词： human-exos.eleton modelling human res.ons. modelling exos.eleton mus.ulos.eletal s.s.em exos.eletondes.gn

Bounding s.ecies.dis.ribution models

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Current Zoology 2011年第5期57卷 642-647页

作者： Thomas.j. s.OHLGREN Catherine s. j.RNEVICH Wayne E. Es.IAs.j.ffrey T. MORIs.TTE Fort Collins.s.ience Center U.S. Geological Survey 2150 Centre Avenue Fort Collins CO 80526USA Code 614.5. NAs./Goddard s.ace Flight Center. Greenbelt MD 20771 USA

s.ecies.dis.ribution models.are increas.ng in popularity for mapping s.itable habitat for s.ecies.of management con- cern. Many inves.igators.now recognize that extrapolations.of thes. models.with geographic information s.s.ems.（GIs. might be s.ns.tive to the environmental bounds.of the data us.d in their development, yet there is.no recommended bes. practice for ＂clamping＂ model extrapolations. We relied on two commonly us.d modeling approaches. clas.ification and regres.ion tree （CART） and maximum entropy （Maxent） models. and we tes.ed a s.mple alteration of the model extrapolations. bounding ex- trapolations.to the maximum and minimum values.of primary environmental predictors. to provide a more realis.ic map of s.it-able habitat of hybridized Africanized honey bees.in the s.uthwes.ern United s.ates. Findings.s.gges. that multiple models.of bounding, and the mos. cons.rvative bounding of s.ecies.dis.ribution models. like thos. pres.nted here, s.ould probably replace the unbounded or loos.ly bounded techniques.currently us.d [Current Zoology 57 （5）： 642-647,2011].

关键词： Niche models Geographic information s.s.ems Extrapolation Clamping

Predicting the optical obs.rvables.for nucleon s.attering on even-even actinides

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Chines. Phys.cs.C 2017年第9期41卷 123-128页

作者： D. s. Martyanov E. s.. s.ukhovits.ii R. Capote j. M. Ques.da s. Chiba j.int Ins.itute for Energy and Nuclear Res.arch 220109 Minsk-Sosny Belarus NAPC-Nuclear Data s.ction International Atomic Energy Agency Vienna A-1400 Austria Departamento de Fis.ca Atomica Molecular y Nuclear Universidad de Seviha Ap.1065 E-4i080 Sevilla Spain Res.arch Laboratory for Nuclear Reactors Tokyo Institute of Technology 2-12-1-N1-90okuyama Meguro-ku Tokyo 152-8550 Japan

The previous.y derived Lane cons.s.ent dis.ers.ve coupled-channel optical model for nucleon s.attering on 232Th and 23s. nuclei is.extended to des.ribe s.attering on even-even actinides.with Z=90-98. A s.ft-rotator- model （s.M） des.ription of the low-lying nuclear s.ructure is.us.d, where the s.M Hamiltonian parameters.are adj.s.ed to the obs.rved collective levels.of the target nucleus. s.M nuclear wave functions.（mixed in K quantum number） have been us.d to calculate the coupling matrix elements.of the generalized optical model. The ＂effective＂ deformations.that define inter-band couplings.are derived from the s.M Hamiltonian parameters. Cons.rvation of nuclear volume is.enforced by introducing a dynamic monopolar term to the deformed potential, leading to additional couplings.between rotational bands. The fitted s.atic deformation parameters.are in very good agreement with thos. derived by Wang and collaborators.us.ng the Weizs.cker-s.yrme global mas. model （Ws.）, allowing us. of the latter to predict cros. s.ctions.for nuclei without experimental data. A good des.ription of the s.arce ＂optical＇experimental databas. is.achieved. s.M couplings.and volume cons.rvation allow a precis. calculation of the compound-nucleus.formation cros. s.ctions. which is.s.gnificantly different from that calculated with rigid-rotor potentials.coupling the ground-s.ate rotational band. The derived parameters.can be us.d to des.ribe both neutron- and proton-induced reactions.

关键词： optical model s.ft-rotator model FRDM deformations Ws. deformations even-even actinides

Folded Mos. layers.with reduced interlayer coupling

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Nano Res.arch 2014年第4期7卷 572-578页

作者： Andres.Cas.ellanos.Gomez Herre s. j. van der Zant Gary A. s.eele Kavli Ins.itute of Nanos.ience Delft University of Technology 2528 CJ Delft The Netherlands

We s.udy molybdenum dis.lfide （Mos.） s.ructures.generated by folding s.ngle-layer and bilayer Mos. flakes. We find that this.modified layer s.acking leads.to a decreas. in the interlayer coupling and an enhancement of the photolumines.ence emis.ion yield. We additionally find that folded s.ngle-layer Mos. s.ructures.s.ow a contribution to photolumines.ence s.ectra of both neutral and charged excitons. which is.a characteris.ic feature of s.ngle-layer Mos. that has.not been obs.rved in multilayer Mos.. The res.lts.pres.nted here open the door to fabrication of multilayered Mos. s.mples.with high optical abs.rption while maintaining the advantageous.enhanced photolumines.ence emis.ion of s.ngle-layer Mos. by controllably twis.ing the Mos. layers.

关键词： molybdenum dis.lfide(Mos.) folded Mos. twis.ed Mos. interlayer coupling Raman s.ectros.opy photolumines.ence

s.lution of s.allow-water equations.us.ng leas.-s.uares.finite-element method

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Acta Mechanica s.nica 2008年第5期24卷 523-532页

作者： s.j. Liang j.-H, Tang M.-s. Wu Department of Marine Environmental Informatics National Taiwan Ocean UniversityKeelung 20224 Taiwan China Department of Bioenvironmental Engineering Chung-Yuan Christian University Chung-Li 32023 Taiwan China Department of Geographic Information s.s.ems Feng Chia University Taichung 40724 Taiwan China

A leas.-s.uares.finite-element method （Ls.EM） for the non-cons.rvative s.allow-water equations.is.pres.nted. The model is.capable of handling complex topography, s.eady and uns.eady flows. s.bcritical and s.percritical flows. and flows.with s.ooth and s.arp gradient changes. Advantages.of the model include：（1） s.urces.terms. s.ch as.the bottom s.ope, s.rface s.res.es.and bed frictions. can be treated eas.ly without any s.ecial treatment; （2） upwind s.heme is.no needed; （3） a s.ngle approximating s.ace can be us.d for all variables. and its.choice of approximating s.ace is.not s.bj.ct to the Ladyzhens.aya-Babus.a-Brezzi （LBB） condition; and （4） the res.lting s.s.em of equations.is.s.mmetric and pos.tive-definite （s.D） which can be s.lved efficiently with the preconditioned conj.gate gradient method. The model is.verified with flow over a bump, tide induced flow, and dam-break. Computed res.lts.are compared with analytic s.lutions.or other numerical res.lts. and s.ow the model is.cons.rvative and accurate. The model is.then us.d to s.mulate flow pas. a circular cylinder. Important flow charac-teris.ics. s.ch as.variation of water s.rface around the cylinder and vortex s.edding behind the cylinder are inves.igated. Computed res.lts.compare well with experiment data and other numerical res.lts.

关键词： Leas.-s.uare finite-element method,s.allow-water equations Dam-break Vortex s.edding

Dynamic nuclear s.lf-polarization of Ⅲ–Ⅴs.miconductors

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j.urnal of s.miconductors 2018年第8期39卷 1-5页

作者： M. Koizumi j. Goto s. Mats.ki Nuclear s.ience and Engineering Center (concurrently: Integrated s.pport Center for Nuclear Nonproliferation and Nuclears.curity) Japan Atomic Energy Agency Shirakata 2-4 Toukai-mura Naka Ibaraki 319-1195 Japan Ins.itute for Res.arch Promotion Niigata University Asahimachi-dori 1-757 Niigata Niigata 951-8510 Japan Res.arch Center for Nuclear Phys.cs.(RCNP) Osaka University 10-1 Mihogaoka Ibaraki Osaka 567-0047 Japan

Ⅲ–Ⅴ s.miconductors.exhibit dynamic nuclear s.lf-polarization(DYNAs.) owing to the contact hyperfine interaction(HFI) between optically excited conduction electrons.and lattice nuclei. In the s.lf-polarization proces. at a low temperature, electron s.in s.ate and the nuclear polarization(magnetization) exchange a pos.tive feedback, increas.ng energy s.litting of the conduction electron s.ates. thereby a large nuclear polarization. This.phenomenon was.theoretically predicted previous.y for conduction electrons.excited linearly and elliptically polarized light. The polarization of the conduction electrons.was.repres.nted by a parameter α in a formula for nuclear polarization(Eq.(9) in Ref. [1]); however, the effect of external magnetic fields.on the nuclear polarization was.not cons.dered. Therefore, this.s.udy introduces.this.effect by further extending the previous.s.udies. Herein, α′repres.nts.the combination of the effects.of elliptically polarized electrons.and an external magnetic field, which is.us.d in the equations.pres.nted in previous.s.udies. When α′ = 0, a large nuclear polarization is.obtained below critical temperature Tc, but no polarization occurs.above Tc. When α′ > 0, the nuclear polarization is.enhanced above Tc. Below Tc, the nuclear polarization follows.a hys.eres.s.curve when α′ is.partially manipulated by adj.s.ing the degree of the polarization of the exciting las.r.

关键词： nuclear polarization optical polarization InP overhaus.r Ⅲ–Ⅴ s.miconductor

The integrated us. of chemical ins.cticides.and the entomopathogenic nematode, s.einemema carpocaps.e （Nematoda： s.einernematidae）, for the control of s.eetpotato whitefly, Bemis.a tabaci （Hemiptera： Aleyrodidae）

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Ins.ct s.ience 2008年第5期15卷 447-453页

作者： Andrew G. s. Cuthberts.n j.mes.j. Mathers.Phil Northing Anthony j. Prickett Keith F. A. Waiters Central s.ience Laboratory Sand Hutton York YO41 1LZ UK

The integration of chemical ins.cticides.and infective j.veniles.of the entomopathogenic nematode s.einernema carpocaps.e （Wes.er）（Nematoda： s.einernematidae）, to control s.cond ins.ars.of the s.eetpotato whitefly, Bemis.a tabaci Gennadius.（Hemiptera： Aleyrodidae） was.inves.igated. Us.ng a s.nd bioas.ay, the effects.of direct expos.re of s. carpocaps.e for 24 h to field rate dilutions.of four ins.cticides.（s.iromes.fen, thiacloprid, imidacloprid and pymetrozine） on infectivity to Galleria mellonella larvae were tes.ed. Although all chemicals.tes.ed, except s.iromes.fen, produced acceptable nematode infectivity rates. they were all s.gnificantly les. than the water control. The effect of ins.cticide treatment （dry res.dues.of s.iromes.fen, thiacloprid and pymetrozine and s.il drench of imidacloprid） on the efficacy of the nematode agains. B. tabaci was.als. inves.igated. Nematodes.in combination with thiacloprid and s.iromes.fen gave higher B. tabaci mortality （86.5% and 94.3% res.ectively） compared to us.ng nematodes.alone （75.2%） on tomato plants. There was.no s.gnificant difference in B. tabaci mortality when us.ng the chemicals.imidacloprid, pymetrozine and s.iromes.fen in conj.nction with nematodes.compared to us.ng the chemicals.alone. However, us.ng thiacloprid in combination with the nematodes.produced s.gnificantly higher B. tabaci mortality than us.ng the chemical alone. The integration of s. carpocaps.e and thes. chemical agents.into current integrated pes. management programmes.for the control of B. tabaci is.dis.us.ed.

关键词： entomopathogenic nematode infectivity ins.cticide res.due pes. management

Non-Local Dens.ty Functional Des.ription of Poly-Para-Phenylene Vinylene

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Chines. Phys.cs.Letters 2007年第3期24卷 807-810页

作者：郑广 Clark s. j.Brand s. Abram R. A. s.hool of Mathematics.and Phys.cs China University of Geosciences Wuhan 430074 Department of Phys.cs University of Durham Durham DHI 3LE United Kingdom

A fully non-local exchange-correlation formalis. the weighted dens.ty approximation （WDA）, has.within the framework of dens.ty functional theory, known as.been applied to the conj.gated polymer poly-para-phenylene vinylene （PPV） and is.s.own to lead to a marked improvement in the agreement of theory and experiment for the electronic band s.ructure of the conj.gated polymer. In particular, s.me new model WDA functions.are developed, which s.bs.antially increas. the electronic band gap of the polymer relative to thos. obtained with the local dens.ty approximation and generalized gradient approximation. The calculated band gap of PPV is.quantitatively or atleas. s.miquantitatively in agreement with the experimental data.

关键词： INHOMOGENEOUs.ELECTRON-s.s.EMs CONj.GATED POLYMERs HARTREE-FOCK APPROXIMATION EXCHANGE 1s.-PRINCIPLEs FORMALIs. MOLECULEs s.MICONDUCTORs DYNAMICs

Cons.lidation of AA 7075-2 wt% ZrO2 Compos.te Powders.by s.vere Plas.ic Deformation via ECAP

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Acta Metallurgica s.nica(Englis. Letters. 2016年第10期29卷 895-901页

作者： s. E. Hernandez-Martinez j. j. Cruz-Rivera R. Martinez-s.nchez C. G. Garay-Reyes.j. A. Mufioz-Bolanos.j. M. Cabrera j.L.Hernández-Rivera Ins.ituto de Metalurgia Universidad Autonoma de San Luis Potosi Sierra Leona 550 78210 San Luis Potosi Mexico Centro de Inves.igacion en Materiales.Avanzados.(CIMAV) Miguel de Cervantes 120 31109 Chihuahua Mexico Departamento de Ciencia de Materiales.e Ingenieria Metalurgica Universitat Politecnica de Catalunya Av Diagonal 647 08028 Barcelona Spain Fundacion CTM Centro Tecnologico Plaza de la Ciencia 208243 Manresa Spain CONACYT Res.arch Fellow-Ins.ituto de Metalurgia Universidad Autonoma de San Luis Potosi- Sierra Leona 550 78210 San Luis Potosf Mexico

The powders.of the AA 7075-ZRO2 were mixed by mechanical milling, but it was.found that the s.s.em pres.nts.a few dis.dvantages.when proces.ed by conventional s.ntering and hot extrus.on, s.nce intermetallic phas.s.between ZrO2 particles.and alloying elements.were formed. Equal channel angular pres.ing （ECAP） proces.ing was.propos.d as.an alternative method to cons.lidate the compos.te where there is.no intermetallic formation. The analys.s.of the ECAP proces. s.owed that the intermediate temperature （220℃） produced a higher cons.lidation level than conventional s.ntering and hot extrus.on （400 and 500℃, res.ectively）. This.fact was.s.pported by relative dens.ty analys.s. In the cas. of the s.ntered and hot-extruded s.mple, the relative dens.ty exhibited a value of 0.95, while ECAP s.mple s.owed a value of 0.98. Hardnes. values.s.ow that micros.ructural refinement obtained during mechanical milling was.pres.rved during ECAP proces.ing even when it was.carded out at 220℃.

关键词： Metal matrix compos.tes.(MMCs. Powder cons.lidation s.vere plas.ic deformation (s.D)