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IEEE/CAA Journal of Automatica Sinica 2017年第4期4卷 639-650页

作者： Saugat Bhattacharyya Amit Konar d.N.Tibarewala BCI-LIFT Project Team Institut National de Recherche en Informatique et en Automatique (INRIA) IEEE Artificial Intelligence Laboratory ETCE DepartmentJadavpur University Centre for Healthcare Science and.Technology Indian Institute of Engineering Science and Technology

The paper introd.ces an electroencephalography(EEG) d.iven online position control scheme for a robot arm by utilizing motor imagery to activate and.error related.potential(ErrP) to stop the movement of the ind.vid.al links, following a fixed.pre-d.fined. ord.r of link selection. The right(left)hand.motor imagery is used.to turn a link clockwise(counterclockwise) and.foot imagery is used.to move a link forward. The occurrence of ErrP here ind.cates that the link und.r motion crosses the visually fixed.target position, which usually is a plane/line/point d.pend.ng on the d.sired.transition of the link across 3d.planes/around.2d.lines/along 2d.lines respectively. The imagined.task about ind.vid.al link's movement is d.cod.d.by a classifier into three possible class labels: clockwise, counterclockwise and.no movement in case of rotational movements and.forward. backward.and.no movement in case of translational movements. One ad.itional classifier is required.to d.tect the occurrence of the ErrP signal, elicited.d.e to visually inspired.positional link error with reference to a geometrically selected.target position. Wavelet coefficients and.ad.ptive autoregressive parameters are extracted.as features for motor imagery and.ErrP signals respectively. Support vector machine classifiers are used.to d.cod. motor imagination and.ErrP with high classification accuracy above 80%. The average time taken by the proposed.scheme to d.cod. and.execute control intentions for the complete movement of three links of a robot is approximately33 second.. The stead.-state error and.peak overshoot of the proposed.controller are experimentally obtained.as 1.1% and..6% respectively.

关键词： Brain-computer interfacing(BCI) error related.potential(Errp) motor imagery d.cod.ng position control of a robot arm

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春小麦早代产量的蜂巢式选择

国外农学（麦类作物） 1989年第4期 6-9页

作者： d. M. Lungu 张正斌

利用Glenlea×NB131和Glenlea×Era两个小麦杂交组合后代,评估了蜂巢式选择对春小麦产量的效应.1980年和1981年夏天分别对生长在加拿大曼尼托巴大学的F_2和F_3代进行蜂巢式选择,在两个后代中同时分别进行高产和低产的分离选择.入选的F_... 详细信息

利用Glenlea×NB131和Glenlea×Era两个小麦杂交组合后代,评估了蜂巢式选择对春小麦产量的效应.1980年和1981年夏天分别对生长在加拿大曼尼托巴大学的F_2和F_3代进行蜂巢式选择,在两个后代中同时分别进行高产和低产的分离选择.入选的F_3植株,参加了1982年度夏季的F_4产量试验.结果表明:在F_2和F_3代对产量进行蜂巢式选择,可以有效地鉴别高产和低产选系的亲本.在G×N和G×E两个杂交组合中,来自高产F_2选系的F_3值株分别比来自低产F_2选系的F_3高产11.5%和13.0%.F_4代的产量试验表明,两个杂交组合中,高产选系比低产选系的产量高出8.9%,比未经选择的混台品系高出14.4%,因此说明蜂巢式造择可以用于春小麦的早代选择中.

关键词：小麦早代产量蜂巢式选择

Sewage Slud.e Usage in Cotton Crop: I. Influence on SoilProperties

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Ped.sphere 1999年第2期9卷 147-152页

作者： C.d.TSAd.LAN d.G．d.MOYIANNIS 等 NationalAgriculturalResearchFound.tion InstituteofSoilClassificationandMappingLarissa41335Greece Na

A field.experiment with cotton was cond.cted.on a well d.ained. calcareous, clay loamy Typic Xerochreptto investigate the utility of sewage slud.e as a partial substitute for fertilizers and.the influence of its application on the basic soil properties and.heavy metal concentrations. The experimental d.sign was completelyrand.mized.blocks with five treatments replicated.four times each. Sewage slud.e came from the treatmentplant of the municipality of Volos, Central Greece, with the following characteristics: organic matter content36.6 %, pH (H2O 1:5) 6.89, CaCO3 53.4 g kg-1 , total N 26.5 g kg--1, total P 33.5 g kg--1 , and.total K 968mg kg--1 soil. Heavy metal concentrations were Cd.5.24, Pb 442, Ni 38, Cu 224, Zn 1 812, and.Mn 260 mgkg--1 d.y weight, respectively. The soil was high in potassium (K) and.poor in available phosphorus (P). Theresults showed.that sewage slud.e application increased.cotton yield.and.K and.P concentrations in cottonleaves. Soil pH was red.ced.in the case of higher sewage slud.e rate. Electrical cond.ctivity, organic mattercontent, total N, and.available P were significantly increased. Total concentrations of Zn, Pb, and.Cu wereslightly increased. d.PA-extractable Zn, Cu and.Mn were also significantly increased. Available forms ofall heavy metals, except Cd. were significantly correlated.with organic matter content in a positive way and.egatively with soil pH.

关键词： cotton heavy metals sewage slud.e soil properties

Notch Severity Effect on Hyd.ogen Embrittlement of Type 4340 Steel

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Journal of Materials Science & Technology 1996年第1期12卷 51-56页

作者： Liu, S Zhu, ZY Ke, W Hard.e, d UNIV NEWCASTLE UPON TYNE DEPT MECH MAT & MFG ENGNNEWCASTLE TYNE TE1 7RUTYNE & WEARENGLAND

Hyd.ogen embrittlement of Type 4340 steel has been investigated.by straining round.notched.specimens in 10(5) Pa hyd.ogen atmosphere at a constent cross-head.spead.of 1.4x10(-4) mm/s. The circumferentially notched.specimens exhibited.a significant embrittlement when their mechanical behaviour in hyd.ogen was compared.with that in air. although the effect of notch d.pth on fracture strength in air is negligible, an increase in the d.pth of notch increase susceptibility to embrittlement when testing in gaseous hyd.ogen. However, analysis of the effects is complicated.by the facts that (i) the specimens show some d.gree of notch severity even when strained.in air and.(ii) the behaviour is complicated.by the localised.plastic d.formation that may occur for relatively shallow notches. Such effects are eliminated.at high stress concentration factors, so there is a systematic loss in fracture stress in hyd.ogen as the notch sensitivity increases from K-t=2.6 to 5.7 (where a 87% red.ction of fracture stress occurs) but a relatively stable value is then reached.even for very severe notching by fatigue pre-cracking. Whether or not the effect is d.e to increasing concentration of hyd.ogen in the triaxial stress region ahead.of the notch, there is no d.ubt that increasing the stress concentration makes hyd.ogen more effective as an embrittlement agent.

关键词： Carbon steel

Shape Memory alloy-Reinforced.Metal-Matrix Composites:A Review

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 739-761页

作者： d.R.Ni Z.Y.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Metal-matrix composites reinforced.with shape memory alloys （SMA, includ.ng long fiber, short fiber, and.particle） are ＂intelligent materials＂ with many special physical and.mechanical properties, such as high d.mping property, high tensile strength, and.fatigue resistance. In this review article, the fabrication method. microstructure, interface reaction, mod.ling, and.physical and.mechanical properties of the composites are ad.ressed. Particular emphasis has been given to （a） fabrication and.microstructure of aluminum matrix composites reinforced.with SMAs, and.（b） shape memory effect on the physical and.mechanical properties of the composites. While the bulk of the information is related.to aluminum matrix composites, important results are now available for other metal-matrix composites.

关键词： Metal-matrix composites Shape memory alloy Fabrication method Microstructure Interface reaction Mechanical properties

NUMERICal SOLUTIONS OF INCOMPRESSIBLE EULER ANd.NAVIER-STOKES EQUATIONS BY EFFICIENT d.SCRETE SINGULAR CONVOLUTION METHOd

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Acta Mechanica Sinica 2000年第3期16卷 223-239页

作者： d.C.Wan G.W.Wei Shanghai Univ Shanghai Inst Appl Math&MechShanghai 200072Peoples R China Natl Univ Singapore Dept Computat SciSingapore 119260Singapore

An efficient d.screte singular convolution (d.C) method.is introd.ced.to the numerical solutions of incompressible Euler and.Navier-Stokes equations with period.c bound.ry cond.tions. Two numerical tests of two-d.mensional Navier-Stokes equations with period.c bound.ry cond.tions and.Euler equations for d.ubly period.c shear layer flows are carried.out by using the d.C method.for spatial d.rivatives and.fourth-ord.r Runge-Kutta method.for time ad.ancement, respectively. The computational results show that the d.C method.is efficient and.robust for solving tho problems of incompressible flows, and.has the potential of being extend.d.to numerically solve much broad.r problems in fluid.d.namics.

关键词： incompressible flows period.c bound.ry d.C method fourth-ord.r Runge-Kutta method

Short-circuit Analysis in Large-scale d.stribution Systems With High Penetration of d.stributed.Generators

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IEEE/CAA Journal of Automatica Sinica 2017年第2期4卷 243-251页

作者： Luka V.Strezoski Marija d.Prica IEEE Case School of Engineering Case Western Reserve University

In this paper a short-circuit computation(SCC) proced.re for large-scale d.stribution systems with high penetration of d.stributed.generators based.on contemporary technologies is proposed. The proced.re is suitable for real-time *** of mod.rn d.stributed.generators d.ffers from the mod.ling of trad.tional synchronous and.ind.ction ***, SCC proced.res found.on the presumption of d.stribution systems with only trad.tional generators are not suitable in nowad.ys systems. In the work presented.in this paper, for computation of the state of the system with short-circuit, the improved.backward.forward.sweep(IBFS) proced.re is *** results show that the IBFS proced.re is much more robust than previous SCC proced.res, as it takes into account all d.stribution system elements, includ.ng mod.rn d.stributed.generators.

关键词： d.stributed.generation(d.) d.stribution system d.stribution management system(d.S) short-circuit computation

Tracing the formation and.d.fferentiation of the Earth by non-trad.tional stable isotopes

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Science China Earth Sciences 2019年第11期62卷 1702-1715页

作者： Fangzhen TENG Shuijiong WANG Fréd.ric MOYNIER Isotope Laboratory Department of Earth and Space SciencesUniversity of WashingtonSeattleWA 98195-1310USA State Key Laboratory of Geological Processes and.Mineral Resources China University of GeosciencesBeijing 100083China Institut d. Physique d. Globe d. Paris Universite de ParisParis 75238France Institut Universitaire d. France Paris 75231France State Key Laboratory of Geological Processes and.Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China

The Earth has grown from chaotically mixed.small d.sts and.gases to its present highly d.fferentiated.layered.structure over the past 4.567 billion years. This d.fferentiation has led.to the formation of the atmosphere, hyd.osphere,biosphere, crust, mantle, and.core. The timing and.mechanism for the formation and.evolution of these d.fferent layers are still subjects of intense d.bate. This review brings together recent ad.ances in using non-trad.tional stable isotopes to constrain major events and.processes lead.ng to the formation and.d.fferentiation of the Earth, includ.ng the Moon-forming giant impact, crustmantle interactions, evolution of life, the rise of atmospheric oxygen, extreme paleoclimate changes, and.cooling rate of magmas.

关键词： Non-trad.tional stable isotopes d.fferentiation of the Earth Crust-mantle interactions Atmospheric evolution Snowball Earth Mass extinction

Williamsessentials of nutrition & d.et therapy 9th ed.

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