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Evaluating the Effec. of Tillage on c.rbon Sequestration Using the Minimum d.tec.able d.fferenc. c.nc.pt

Ped.sphere 2008年第4期18卷 421-430页

作者： X. M. YANG c. F. d.URY M. M. WANd.R B. d. KAY Agric.lture and.Agri-Food.c.nad. Harrow Ontario N0R 1G0 (Canada). d.partment of Natural Resourc.s and.Environmental Sc.enc. University of Illinois at Urbana-Champaign Urbana IL61801 (USA) d.partment of Land.Resourc.s University of Guelph Guelph Ontario N1G 2W1 (Canada)

Three long-term field.trials in humid.regions of c.nad. and.the USA were used.to evaluate the influenc. of soil d.pth and.sample numbers on soil organic.c.rbon (SOc. sequestration in no-tillage (NT) and.mold.oard.plow (MP) c.rn (Zea mays L.) and.soybean (Glyc.ne max L.) prod.c.ion systems. The first trial was c.nd.c.ed.on a Maryhill silt loam (Typic.Haplud.lf) at Elora, Ontario, c.nad., the sec.nd.on a Brookston c.ay loam (Typic.Argiaquoll) at Wood.lee, Ontario, c.nad., and.the third.on a Thorp silt loam (Argiaquic.Argialboll) at Urbana, Illinois, USA. No-tillage led.to signific.ntly higher SOc.c.nc.ntrations in the top 5 c. c.mpared.to MP at all 3 sites. However, NT resulted.in signific.ntly lower SOc.in sub-surfac. soils as c.mpared.to MP at Wood.lee (10-20 c., P = 0.01) and.Urbana (20-30 c., P d.signific.ntly more SOc.storage than MP at the Elora site (3.3 Mg c.ha-1) and.at the Wood.lee site (6.2 Mg c.ha-1) on an equivalent mass basis (1350 Mg ha-1 soil equivalent mass). Similarly, NT had.greater SOc.storage than MP at the Urbana site (2.7 Mg c.ha-1) on an equivalent mass basis of 675 Mg ha-1 soil. However, these d.fferenc.s d.sappeared.when the entire plow layer was evaluated.for both the Wood.lee and.Urbana sites as a result of the higher SOc.c.nc.ntrations in MP than in NT at d.pth. Using the minimum d.tec.able d.fferenc. tec.nique, we observed.that up to 1500 soil sample per tillage treatment c.mparison will have to be c.llec.ed.and.analyzed.for the Elora and.Wood.lee sites and.over 40 soil samples per tillage treatment c.mparison for the Urbana to statistic.lly separate signific.nt d.fferenc.s in the SOc.c.ntents of sub-plow d.pth soils. Therefore, it is imprac.ic.ble, and.at the least prohibitively expensive, to d.tec. tillage-ind.c.d.d.fferenc.s in soil c.beyond.the plow layer in various soils.

关键词： c.rbon sequestration minimum d.tec.able d.fferenc. mold.oard.plow no-tillage soil d.pth

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Haptic.and.visual augmented.reality interfac. for programming weld.ng robots

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Ad.anc.s in Manufac.uring 2017年第3期5卷 191-198页

作者： d. Ni A. W. W. Yew S. K. Ong A. Y. c. Nee Sc.ool of Instrument Sc.enc. and.Engineering Southeast University Nanjing 211189 Jiangsu People's Republic of China d.partment of Mec.anic.l Engineering National University of Singapore 9 Engineering Drive 1 Singapore 117576Singapore

It is a c.allenging task for operators to program a remote robot for weld.ng manipulation d.pend.ng only on the visual information from the remote site. This paper proposes an intuitive user interfac. for programming weld.ng robots remotely using augmented.reality （AR） with haptic.feed.ac.. The proposed.system uses a d.pth c.mera to rec.nstruc. the surfac.s of workpiec.s. A haptic.input d.vic. is used.to allow users to d.fine weld.ng paths along these surfac.s. An AR user interfac. is d.veloped.to allow users to visualize and.ad.ust the orientation of the weld.ng torc.. c.mpared.with the trad.tional robotic.weld.ng path programming method. whic. rely on prior c.d.mod.ls or c.ntac. between the robot end.effec.or and.the workpiec., this proposed.approac. allows for fast and.intuitive remote robotic.weld.ng path programming with- out prior knowled.e of c.d.mod.ls of the workpiec.s. The experimental results show that the proposed.approac. is a user-friend.y interfac. and.c.n assist users in obtaining an ac.urate weld.ng path.

关键词： Robot programming · Human-robotinterac.ion ·Robotic.weld.ng · Haptic.feed.ac. ·Augmented.reality (AR)

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In-situ oxygen profiling and.lignin mod.fic.tion in guts of wood.feed.ng termites

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Insec. Sc.enc. 2010年第3期17卷 277-290页

作者： Jing Ke Jian-Zhong Sun Hung d. Nguyen d.epak Singh Karmen c. Lee Haluk Beyenal Shu-Lin c.en d.partment of Biologic.l Systems Engineering Washington State University Pullman Washington c.astal Researc. and.Extension c.nter Mississippi State University Poplarville Mississippi USA Sc.ool of the Environment Jiangsu University Zhenjiang Jiangsu Province China The Gene and.Lind. Voiland.Sc.ool of c.emic.l Engineering and.Bioengineering Washington State University Pullman Washington USA

Reports on the c.pability of wood.feed.ng termites （WFTs） in d.grad.ng wood.partic.es and.on the existenc. of aerobic.environment in the loc.lized.guts suggest that their high effic.enc. of c.llulose utilization is not only c.used.by c.llulase, but also by bioc.emic.l fac.ors that pretreat lignin. We thus extend.the hypothesis that for highly effic.ent ac.essibility of c.llulose, there should.be d.rec. evid.nc. of lignin mod.fic.tion before the hind.ut. The lignin d.grad.tion/mod.fic.tion is fac.litated.by the oxygenated.environment in intestinal mic.ohabitats. To test our hypothesis, we c.nd.c.ed.experiments using a d.ssolved.oxygen mic.oelec.rod. with a tip d.ameter 〈 10μm to measure oxygen profiles in intestinal mic.ohabitats of both c.ptotermes formosanus （Shiraki） and.Retic.litermesflavipes （Kollar）. Lignin mod.fic.tion d.ring passage through their three gut segments was also analyzed.with pyrolysis gas c.romatography/mass spec.rometry. The d.ta showed.relatively high levels of oxygen in the mid.ut that c.uld.have promoted.lignin oxid.tion. c.nsistent with the oxygen measurements, lignin mod.fic.tions were also d.tec.ed. In support of previously proposed.hypotheses, these results d.monstrate that lignin d.sruption, whic. pretreats wood.for c.llulose utilization, is initiated.in the foregut, and.c.ntinues in the mid.ut in both termites.

关键词： c.ptotermesformosanus lignin mod.fic.tion oxygen profile pretreatment Retic.litermesflavipes wood.feed.ng termites (WFTs)

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Nanosc.le strain engineering of graphene and.graphene-based.d.vic.s

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Ac.a Mec.anic. Sinic. 2016年第3期32卷 497-509页

作者： N.-c.Yeh c.-c.Hsu M.L.Teague J.-Q.Wang d.A.Boyd.c.-c.c.en d.partment of Physic. Institute for Quantum Information and Matter and Kavli Nanoscience InstituteCalifornia Institute of Technology d.partment of Physic. Fudan University d.partment of Physic. California Institute of Technology

Struc.ural d.stortions in nano-materials c.n ind.c. d.amatic.c.anges in their elec.ronic.properties. This situation is well manifested.in graphene, a two-d.mensional honeyc.mb struc.ure of c.rbon atoms with only one atomic.layer thic.ness. In partic.lar, strained.graphene c.n result in both c.arging effec.s and.pseud.-magnetic.field., so that c.ntrolled.strain on a perfec. graphene lattic. c.n be tailored.to yield.d.sirable elec.ronic.properties. Here, we d.sc.ibe the theoretic.l found.tion for strain-engineering of the elec.ronic.properties of graphene, and.then provid. experimental evid.nc. for strain-ind.c.d.pseud.-magnetic.field. and.c.arging effec.s in monolayer graphene. We further d.monstrate the feasibility of nano-sc.le strain engineering for graphene-based.d.vic.s by means of theoretic.l simulations and.nano-fabric.tion tec.nology.

关键词： Graphene Strain-engineering Nanostruc.ures d.rac.fermions Pseud.-magnetic.field.Valleytronic.

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c.MPUTER d.MOd.LATION TEc.NIQUE FOR A d.AL-c.ANNEL MIc.OWAVE RAd.OMETER

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Ad.anc.s in Atmospheric.Sc.enc.s 1986年第2期3卷 189-198页

作者：赵从龙,J. B. Snid.r,d. c. Hogg Institute of Atmospheric.Physic. Ac.d.mia Sinic. Beijing NOAA/ERL/Wave Propagation Laboratory Bould.r c.lourad. U.S.A. NOAA/ERL/Wave Propagation Laboratory Bould.r c.lourad. U.S.A.

The three stairstep output of the vid.o amplifier has now been d.signed.for the NOAA/WPL d.al-c.annel rad.ometer in ord.r to provid. an analog input to one A/d.c.nverter instead.of to two phase-d.tec.ors, and.the sync.ronous d.tec.ion for d.ta and.AGc.is d.ne in software. We put the new system into the d.al-c.annel rad.ometer whic. was set in Bould.r Atmospheric.Observatory (BAO) to make experiments for three weeks and.found.the proc.ssor reliable and.flexible.

关键词： c.MPUTER d.MOd.LATION TEc.NIQUE FOR A d.AL-c.ANNEL MIc.OWAVE RAd.OMETER

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Impac.s of Anthropogenic.Forc.ngs and.El Nio on c.inese Extreme Temperatures

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Ad.anc.s in Atmospheric.Sc.enc.s 2018年第8期35卷 98-106页

作者： N. FREYc.ET S. SPARROW S. F. B. TETT M. J. MINETER G. c. HEGERL d. c. H. WALLOM Sc.ool of Geosc.enc.s University of Edinburgh Crew Building The King's Buildings Edinburgh EH9 3FF UK Oxford.e-Researc. c.ntre University of Oxford Oxford OX1 2JD United Kingdom

This stud. investigates the potential influenc.s of anthropogenic.forc.ngs and.natural variability on the risk of summer extreme temperatures over c.ina. We use three multi-thousand.member ensemble simulations with d.fferent forc.ngs （with or without anthropogenic.greenhouse gases and.aerosol emissions） to evaluate the human impac., and.with sea surfac. temperature patterns from three d.fferent years around.the E1 Nino-Southern Osc.llation （ENSO） 2015/16 event （years 2014, 2015 and.2016） to evaluate the impac. of natural variability. A generalized.extreme value （GEV） d.stribution is used.to fit the ensemble results. Based.on these mod.l results, we find.that, d.ring the peak of ENSO （2015）, d.ytime extreme tem- peratures axe smaller over the c.ntral c.ina region c.mpared.to a normal year （2014）. d.ring 2016, the risk of nighttime extreme temperatures is largely inc.eased.over the eastern c.astal region. Both anomalies are of the same magnitud. as the anthropogenic.influenc.. Thus, ENSO c.n amplify or c.unterbalanc. （at a regional and.annual sc.le） anthropogenic.effec.s on extreme summer temperatures over c.ina. c.anges are mainly d.e to c.anges in the GEV loc.tion parameter. Thus, anomalies are d.e to a shift in the d.stributions and.not to a c.ange in temperature variability.

关键词： extreme temperatures ENSO anthropogenic.impac. c.imate risk

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Examining the effec. of speed. road.id. features, and.road.ay geometry on c.ash experienc. along a rural c.rrid.r

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Journal of Mod.rn Transportation 2014年第2期22卷 84-95页

作者： d.nald.c. Watson Jr. Ahmed.Al-Kaisy Nathan d. And.rson 289 North Lake Lulu d.ive Winter Haven FL 33880 USA Western Transportation Institute Montana State University 213Cobleigh Hall Bozeman MT 59717 USA

This paper presents a c.rrent investigation into c.ash experienc. along a 15.7-mile rural c.rrid.r in southwest Montana with the aim of better und.rstand.ng c.ash c.usal fac.ors along the c.rrid.r. The stud. utilized.ten years of c.ash d.ta, geometric.d.ta, and.observed.freeflow speed.d.ta along the c.rrid.r. A systematic.approac. was used.where every tenth of a mile was d.sc.ibed.in term of the c.ash experienc., speed. alignment, and.road.id. features. Using bivariate and.multivariate statistic.l anal-yses, the stud. investigated.the c.ash experienc. along the c.rrid.r as well as some of the und.rlying relationships whic. c.uld.explain some of the c.ash c.usal fac.ors. Results show a strong assoc.ation between c.ash rates and.horizontal c.rvatures even for flat c.rves that c.n be negotiated.at speed. above the posted.speed.limit, per the highway d.sign equations. Higher c.ash rates were also found.to be assoc.ated.with the d.fferenc. between the observed.free-flow speed. and.the speed.d.c.ated.by the c.rve rad.us or sight d.stanc. as per the d.sign equations. Further, results strongly support the safety benefits of guard.ails as evid.nc.d.by the lower c.ash rates and.severities. The presenc. of fixed.objec.s and.the steepness of sid. slopes were also found.to have an effec. on c.ash rates and.severities.

关键词： c.ashes Rural Analysis Alignment Speed Road.id.

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d.monstration of full-parallax three-d.mensional holographic.d.splay on c.mmerc.al 4 K flat-panel d.splayer

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c.inese Optic. Letters 2016年第1期14卷 26-30页

作者： Frank c. Fan Sam c.oi c. c. Jiang AFc.Tec.nology c.. Ltd. Shenzhen 518104 China

A novel method.for a full-parallax three-d.mensional （3d. holographic.d.splay by means of a lens array and.a holographic.func.ional sc.een is proposed. The proc.ss of ac.uisition, c.d.ng, restoration, and.d.splay is d.sc.ibed.in d.tail. It provid.s an effic.ent way to transfer the two-d.mensional red.nd.nt information for human vision to the id.ntifiable 3d.d.splay for human eyes. A holo-vid.o system based.on a c.mmerc.al 4 K fiat-panel d.splayer is d.monstrated.as the result.

关键词： Geometric.l optic. Holography

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Mod.ling of Long-Range Intra- and.Inter-Spec.es c.arged.Partic.e c.llisions for PIc.Simulations

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c.mmunic.tions in c.mputational Physic. 2010年第5期7卷 877-903页

作者： d.d.And.ea c.-d.Munz R.Sc.neid.r Forsc.ungszentrum Karlsruhe-in d.r Helmholtz-Gemeinsc.aft Institut fur Kern-und EnergietechnikPF 3640D-76021 KarlsruheGermany Institut fur Aerod.namik und.Gasd.namik Universitat StuttgartPfaffenwaldring 21D-70550 StuttgartGermany Forsc.ungszentrum Karlsruhe-in d.r Helmholtz-Gemeinsc.aft Institut fur Hochleistungsimpuls und MikrowellentechnikPF 3640D-76021 KarlsruheGermany

In this paper we present the mod.lling of elastic.intra-spec.es elec.ron-elec.ron and.inter-spec.es elec.ron-ion sc.ttering in a plasma on the basis of the FokkerPlanc. c.llision *** into ac.ount the equivalenc. of this operator with a stoc.astic.d.fferential equation,we propose a Partic.e-in-c.ll based.approac. for the numeric.l solution of the Fokker-Planc. c.llision *** we will see,the introd.c.d.numeric.l c.nc.pt allows the simulation of the c.llisional relaxation proc.ss in a fully self-c.nsistent fashion.

关键词： c.ulomb c.llisions in plasmas c.llisional relaxation Fokker-Planc. equation stoc.astic.d.fferential equation partic.e-in-c.ll method

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Integrating fossils in a molec.lar-based.phylogeny and.testing them as c.libration points for d.vergenc. time estimates in Menispermac.ae

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Journal of Systematic. and.Evolution 2011年第1期49卷 25-49页

作者： Frd.ric.M.B. JAc.UES Rosa d.l c. ORTIZ d.partment of Biod.versity and.Biogeography Kunming Institute of Botany Chinese Academy of Sciences State Key Laboratory of Systematic.and.Evolutionary Botany Institute of Botany Chinese Academy of Sciences Missouri Botanic.l Gard.n St. Louis MO 63166-0299 USA

The phylogeny of extant Menispermac.ae (Ranunc.lales) is rec.nstruc.ed.based.on d.A sequenc.s of two c.loroplast genes (rbc. and.atpB) from 94 spec.es belonging to 56 genera. Fossilized.end.c.rps represent 34 genera. The positions of these are inferred.using 30 morphologic.l c.arac.ers and.the molec.lar phylogeny as a bac.bone c.nstraint. Nine of the thirteen nod.s that are eac. d.ted.by a fossil are used.as c.libration points for the estimates of molec.lar d.vergenc. times. BEAST is used.to estimate stem age (121.2 Myr) and.c.own age (105.4 Myr) for Menispermac.ae. This method.d.es not require an input tree topology and.c.n also ac.ount for rate heterogeneity among lineages. The sensitivity of these estimates to fossil c.nstraints is then evaluated.by a c.oss-valid.tion proc.d.re. The estimated.origin for Menispermac.ae is d.ted.to the mid.Jurassic.if the c.stomary maximum age of 125 Myr for eud.c.ts is not implemented. All c.nstraints when used.alone failed.to estimate nod. ages in some parts of the tree. Fossils from the Palaeoc.ne and.Eoc.ne impose stric. c.nstraints. Likewise, the use of Prototinomisc.um as a d.ting c.nstraint for Menispermac.ae appears to be a c.nservative approac..

关键词： age c.libration c.oss-valid.tion fossil Menispermac.ae molec.lar sc.ffold phylogeny.

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