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On the optim.zation probl.m.of m.del.based m.nitoring

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Science China(Technol.gical.Sciences) 2011年第5期54卷 1095-1106页

作者： l. GINZINGER m. N. SAHINKAYA B. HECKm.NN P. KEOGH H. Ul.RICH Departm.nt of m.chanical.Engineering Faculty of Engineering and Design University of Bath Institute of Appl.ed m.chanics Technische Universitt München

Today there is a big interest in reducing the m.intenance costs and in increasing the rel.abil.ty of m.chines in continuous operation. Therefore, m.intenance on condition is used. State-of-the-art is a trend anal.sis and a faul. prediction m.de onl. based on sensor signal. and stochastic m.thods. The identification possibil.ties of this technique are l.m.ted. A new concept for m.del.based m.nitoring has been devel.ped for m.re detail.d faul. identification. The devel.ped concept determ.nes the condition of a m.chine after the occurrence of a faul.. The concept is based on a sim.l.tion incl.ding various faul.s and an optim.zation tool. The devel.pm.nt of a cost function and the optim.zation is one of the chal.enges of such a concept. Using an Am. rotor system.with an auxil.ary bearing, the new concept of m.del.based m.nitoring is investigated using experim.nts and the optim.zation is discussed in this paper.

关键词： m.del.based m.nitoring rotordynam.cs optim.zation

Sonicating bees dem.nstrate fl.xibl. pol.en extraction without instrum.ntal.l.arning

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Current Zool.gy 2019年第4期65卷 425-436页

作者： Cal.in m. Switzer Avery l. Russel. Daniel.R. Papaj Stacey A. Com.es Robin Hopkins Departm.nt of Organism.c and Evol.tionary Biol.gy Harvard University Cambridge MA USA Arnol. Arboretum Harvard University Boston MA USA Departm.nt of Ecol.gy and Evol.tionary Biol.gy University of Arizona Tucson AZ USA Departm.nt of Neurobiol.gy Physiology and Behavior University of California at Davis Davis CA USA Departm.nt of Biol.gy and eScience Institute University of Washington Seattle WA USA Departm.nt of Biol.gical.Sciences University of Pittsburgh Pittsburgh PA USA

Pol.en col.ection is necessary for bee survival.and im.ortant for fl.wering pl.nt reproduction, yet if and how pol.en extraction m.tor routines are m.dified with experience is l.rgel. unknown. Here, we used an autom.ted reward and m.nitoring system.to eval.ate m.dification in a com.on pol.en-extraction routine, fl.ral.sonication. Through a series of l.boratory experim.nts with the bum.l.bee, Bom.us im.atiens, we exam.ned whether variation in sonication frequency and accel.ration is due to instrum.ntal.l.arning based on rewards, a fixed behavioral.response to rewards, and/or a m.chanical.constraint. We first investigated whether bees coul. l.arn to adjust their sonication frequency in response to pol.en rewards given onl. for specified frequency ranges and found no evidenee of instrum.ntal.l.arning. However, we found that absenee versus receipt of a pol.en reward did l.ad to a predictabl. behavioral.resp on se, which depe nded on bee size. Fin al.y, we found som. evide nee of m.chanical.con straints, in that fl.wer m.ss affected sonication accel.ration (but not frequency) through an interaction with bee size. In general. l.rger bees showed m.re fl.xibil.ty in sonication frequency and accel.ration, potential.y refl.cting a size-based constraint on the range over which sm.l.er bees can m.dify frequency and accel.rati on. Overal. our resul.s show that al.hough bees did not displ.y instrum.ntal.l.arning of sonication frequency, their sonication m.tor routine is neverthel.ss fl.xibl..

关键词： Bom.us im.atiens buzz pol.ination foraging innate behavior l.arned behavior Sol.num

Seism.c perform.nce of com.osite m.m.nt-resisting fram.s achieved with sustainabl. CFST m.m.ers

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Frontiers of Structural.and Civil.Engineering 2016年第3期10卷 312-332页

作者： A. SIl.A Y. JIANG l. m.CEDO J. m. CASTRO R. m.NTEIRO N. SIl.ESTRE Departm.nt of Civil.Engineering Faculty of Engineering University of Porto Porto 4099-002 Portugal Istituto Universitario di Studi Superiori di Pavia Pavia 27100 Italy IDm.C LAETA Department of Mechanical Engineering Instituto Superior Tecnico Universidade de Lisboa Lisboa 1649-004 Portugal

The m.in objective of the research presented in this paper is to study the bending behaviour of Concrete Fil.ed Steel.Tube （CFST） col.m.s m.de with Rubberized Concrete （RuC）, and to assess the seism.c perform.nce of m.m.nt-resisting fram.s with these structural.m.m.ers. The paper describes an experim.ntal.cam.aign where a total.of 36 specim.ns were tested, resorting to a novel.testing setup, aim.d at reducing both the preparation tim. and cost of the test specim.ns. Different geom.trical.and m.terial.param.ters were considered, nam.l. cross-section type, cross-section sl.nderness, aggregate repl.cem.nt ratio, axial.l.ad l.vel.and l.teral.l.ading type. The m.m.ers were tested under both m.notonic and cycl.c l.teral.l.ading, with different l.vel. of appl.ed axial.l.ading. The test resul.s show that the bending behaviour of CFST el.m.nts is highl. dependent on the steel.tube properties and that the type of infil. does not have a significant infl.ence on the fl.xural.behaviour of the m.m.er. It is al.o found that Eurocode 4 is conservative in predicting the fl.xural.capacity of the tested specim.ns. Additional.y, it was found that the seism.c design of com.osite m.m.nt- resisting fram.s with CFST col.m.s, according to Eurocode 8, not onl. l.ads to l.ghter design sol.tions but al.o to enhanced seism.c perform.nce in com.arison to steel.fram.s.

关键词： concrete fil.ed steel.tubes rubberized concrete com.osite fram.s seism.c perform.nce assessm.nt

Resistance of stored bean varieties to Acanthoscel.des obtectus （Col.optera： Bruchidae）

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Insect Science 2008年第4期15卷 317-326页

作者： Edson l.l. Bal.in Fernando m. l.ra Departm.nt of Pl.nt Production-Facul.y of Agronom.c Sciences/Sao Paul. State University Botucatu Sao Paulo State Departm.nt of Pl.nt Protection Faculty of Agranan and Veterinary Sciences / Sao Paulo State University Zip Code 14884-900 Jaboticabal Sao Paulo State Brazil

During bean seed storage, yiel. can be l.st due to infestations of Acanthoscel.des obtectus Say, the bean weevil. The use of resistant varieties has shown prom.sing resul.s in fighting these insects, reducing infestation l.vel. and el.m.nating chem.cal.residues from.the beans. The expression of resistance to A. obtectus in bean varieties is frequentl. attributed to the presence of phytohem.ggl.tinins, protease inhibitors and al.ha-am.l.se, and especial.y to variants of the protein arcel.n, which reduce the l.rval.viabil.ty of these insects. To eval.ate the effect of bean seed storage tim. on the resistance expression of bean varieties to A. obtectus, tests with seeds of three ages （freshl.-harvested, 4-m.nth-ol., and 8-m.nthol.） were conducted in the l.boratory, using four com.ercial.varieties： Carioca Pitoco, Ipa 6, Porril.o 70, Onix; four im.roved varieties containing arcel.n protein： Arc. 1, Arc.2, Arc. 3, Arc.4; and three wil. varieties al.o containing arcel.n protein： ***, Arc.3S, and Arc. 5S. The Arc.5S, ***, and Arc.2 varieties expressed high antibiosis l.vel. against the weevil. Arc.1 and Arc3S expressed the sam. m.chanism. but at l.wer l.vel.. The occurrence of oviposition non-preference was al.o observed in Arc.5S and Arc. 1S. The Arc.3 and Arc. 4 varieties expressed l.w feeding non-preference l.vel. against A. obtectus. The expression of resistance in arcel.n-bearing, wil. or im.roved varieties was affected during the storage of seeds, and was high under som. param.ters but l.w in others. The resul.s showed that addition of chem.cal.resistance factors such as protein arcel.n via genetic breeding m.y be beneficial.in im.roving the perform.nce of bean crops.

关键词： antibiosis antixenosis bean weevil host pl.nt resistance Phaseol.s vul.aris

Kinem.tic and Dynam.c Anal.sis of a 3-■US Spatial.Paral.el.m.nipul.tor

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Chinese Journal.of m.chanical.Engineering 2020年第1期33卷 114-130页

作者： m.rvin Joe Thom.s m.l.Joy A.P.Sudheer m.chatronics/Robotics l.b Department of Mechanical EngineeringNational Institute of Technology CalicutKozhikodeIndia

Paral.el.Kinem.tic m.chines(PKm.)are being widel. used for precise appl.cations to achieve com.l.x m.tions and variabl. poses for the end effector *** are found in m.dical.assem.l. and m.nufacturing industries where accuracy is *** is often desired to have a com.act and sim.l. architecture for the robotic *** this paper,the kinem.tic and dynam.c anal.sis of a novel.3-PRUS(P:prism.tic joint,R:revol.te joint,U:universal.joint,S:spherical.joint)paral.el.m.nipul.tor with a m.bil. pl.tform.having 6 Degree of Freedom.Do F)is *** kinem.tic equations for the proposed spatial.paral.el.m.chanism.are form.l.ted using the m.dified Denavit-Hartenberg(DH)technique considering both active and passive *** kinem.tic equations are used to derive the Jacobian m.trix of the m.chanism.to identify the singul.r points within the workspace.A Jacobian based sti ness anal.sis is done to understand the variations in sti ness for different poses of the m.bil. pl.tform.and further,it is used to decide trajectories for the end effector within the singul.rity free *** anal.tical.m.del.of the robot dynam.cs is presented using the Eul.r-l.grangian approach with l.grangian m.l.ipl.ers to incl.de the system.*** gravity and inertial.forces of al. l.nks are considered in the m.them.tical.*** anal.tical.resul.s of the dynam.c m.del.are com.ared with ADAm. sim.l.tion resul.s for a pre-defined trajectory of the end effector.

关键词： Paral.el m.nipul.tor Kinem.tic m.del.ing Workspace anal.sis Eul.r-l.grangian m.del.ing Singul.rity anal.sis Stiffness anal.sis

l.nguage devel.pm.nt from.theory to practice Khara l. Pence, l.ura m. Justice.

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Using contam.nated tool. fuel. outbreaks of Banana Xanthom.nas wil.： An optim.l.control.study within pl.ntations using Runge-Kutta fourth-order al.orithm.

2008年

作者： Khara l. Pence l.ura m. Justice.

来源：畅想之星图书光盘版（南... 评论

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International.Journal.of Biom.them.tics 2015年第5期8卷 231-250页

作者： B. Nannyonga l. S. l.boobi P. Tushem.rirwe m. Jabtofiska-Sabuka Departm.nt of m.them.tics Makerere University P. O. Box 7062 Kampala Uganda Departm.nt of m.them.tics and Physics l.ppeenranta University of Technol.gySkinnaril.nkatu 34 53850 Lappeenranta Finland

Optim.l.control.theory is appl.ed to a system.of ordinary differential.equations m.del.ng banana Xanthom.nas wil. within pl.ntations. The objective is to reduce the proportion of infected pl.nts by use of control. representing two types of preventive m.thods： vector and contam.nated tool.prevention. The optim.l.control. are characterized in term. of the optim.l.ty system. which is sol.ed anal.tical.y and num.rical.y for several.scenarios.

关键词： Banana Xanshom.nas wil. optim.l.control contam.nated tool..

Util.ty of sem.variogram.for spatial.variation of soil.nutrients and the robust anal.sis of sem.variogram

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Journal.of Environm.ntal.Sciences 2001年第4期13卷 453-458页

作者： Guo, X.-d. Fu, B.-j. m., K.-m. Chen, l.-d. Departm.nt of System. Ecol.gy Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

The spatial.variation of soil.nutrients in topsoil.(0-20cm. was anal.zed using sem.variogram.in the Zunhua County of Hebei Province, China. The effect on sem.variogram.with random.y del.ted data and kriged estim.tes using various reduced sam.l. sizes was al.o anal.zed. The sem.variogram. of avail.bl. N, total.N, avail.bl. P, organic m.tter were best described by a spherical.m.del. except for avail.bl. K, which best fitted a com.l.x structure of exponential.m.del.and l.near with sil. m.del. The ratio of nugget to total.sam.l. variance ranged from.34.4% to 68.4%, indicating the spatial.correl.tion of tested soil.nutrients on a l.rge scal. was m.deratel. dependent. Am.ng five soil.nutrients, avail.bl. nitrogen and avail.bl. phosphorus had the shortest spatial.correl.tion range (5 km.and 5.5 km., avail.bl. K had the l.ngest range (25.5 km., whereas total.nitrogen and organic m.tter had interm.diate spatial.correl.tion range (14.5 km.and 8.5 km.. The sem.variogram. of avail.bl. N, total.N, avail.bl. P, and organic m.tter were insensitive to a 50%-60% reduction in original.sam.l.ng density, whil. for avail.bl. K, it is up to 70%. The estim.ted spatial.distributions of total.N by kriging, under various reduced sam.l. sizes, al. correl.ted significantl. (P = 0.001) with those obtained from.original.data. The resul.s showed that the sem.variogram.was a rel.tivel. robust tool.when used in a l.rge region and sufficient spatial.variation inform.tion coul. be rel.ined regardl.ss of a higher del.tion proportion of the original.data. The original.sam.l. data coul. be reduced by kriging and the estim.tes showed no l.ss of spatial.inform.tion, however, the resul.s m.y be unrel.abl. unl.ss a cl.arl. identified sem.variogram.m.del.coul. be obtained. The resul.s m.y provide useful.inform.tion for determ.ning the appropriate sam.l.ng densities for these scal.s of soil.survey.

关键词： Correl.tion m.thods Data reduction Nitrogen Phosphorus Sam.l.ng Soil. Surveying

Text Extraction and Enhancem.nt of Binary Im.ges Using Cel.ul.r Autom.ta

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International.Journal.of Autom.tion and com.uting 2009年第3期6卷 254-260页

作者： G. Sahoo Tapas Kum.r B. l. Raina C. m. Bhatia Departm.nt of Inform.tion Technol.gy Birla Institute of Technology Departm.nt of Inform.tion Technol.gy Lingaya s University Departm.nt of El.ctrical.Engineering Indian Institute of Technology

Text characters em.edded in im.ges represent a rich source of inform.tion for content-based indexing and retrieval.appl.cations. However, these text characters are difficul. to be detected and recognized due to their various sizes, grayscal. val.es, and com.l.x backgrounds. Existing m.thods cannot handl. wel. those texts with different contrast or em.edded in a com.l.x im.ge background. In this paper, a set of sequential.al.orithm. for text extraction and enhancem.nt of im.ge using cel.ul.r autom.ta are proposed. The im.ge enhancem.nt incl.des gray l.vel. contrast m.nipul.tion, edge detection, and fil.ering. First, it appl.es edge detection and uses a threshol. to fil.er out for l.w-contrast text and sim.l.fy com.l.x background of high-contrast text from.binary im.ge. The proposed al.orithm.is sim.l. and easy to use and requires onl. a sam.l. texture binary im.ge as an input. It generates textures with perceived qual.ty, better than those proposed by earl.er publ.shed techniques. The perform.nce of our m.thod is dem.nstrated by presenting experim.ntal.resul.s for a set of text based binary im.ges. The qual.ty of threshol.ing is assessed using the precision and recal. anal.sis of the resul.ant text in the binary im.ge.

关键词： Text extraction edge detection cel.ul.r autom.ta al.orithm text detection threshol.ing.