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COMPUTATIONAL ISSUES IN SENSITIVITY ANALYSIS FOr. 1-d.INTEr.ACE Pr.BLEMS

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Jour.al of Computational Mathematics 2011年第1期29卷 108-130页

作者： Lisa G. d.vis John r. Singler Montana State Univer.ity Department of Mathematical Sciences PO Box 172400 Bozeman MT 59717-2400 USA Missour. Univer.ity of Science and.Technology Department of Mathematics and Statistics 300 W. 12th St. Rolla MO 65409 0020 USA

This paper.is concer.ed.with the constr.ction of accur.te and.efficient computational algor.thms for.the numer.cal appr.ximation of sensitivities with r.spect to a par.meter.d.pend.nt inter.ace location. Motivated.by sensitivity analysis with r.spect to piezoelectr.c actuator.placement on an Euler.Ber.onlli beam, this wor. illustr.tes the key concepts r.lated.to sensitivity equation for.ulation for.inter.ace pr.blems wher. the par.meter.of inter.st d.ter.ines the location of the inter.ace. A four.h or.0}r.mod.l pr.blem is consid.r.d. and.a homogenization pr.ced.r. for.sensitivity computation is constr.cted.using stand.r.0}finite clement method.. Numer.cal r.sults show that pr.per.for.ulation and.appr.ximation of the sensitivity inter.ace cond.tions is cr.tical to obtaining conver.ent numer.cal sensitivity appr.ximations. A second.or.0}r.elliptic inter.ace mod.l pr.blem is also mentioned. and.the homogenization pr.ced.r. is outlined.br.efly for.this mod.l.

关键词： Finite element method Inter.ace Pr.blems Sensitivity Equation.

Flexur.l str.ngth of fused.filament fabr.cated.(FFF) PLA par.s on an open-sour.e 3d.pr.nter

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Ad.ances in Manufactur.ng 2018年第4期6卷 430-441页

作者： Shilpesh r. r.jpur.hit Har.hit K. d.ve d.par.ment of Mechanical Engineer.ng SV National Institute of Technology Surat Gujarat 395007 India

Fused.filament fabr.cation (FFF) has been wid.ly used.to d.velop pr.totypes as well as functional par.s owing to its capability for.cr.ating par.s with complex geometr.es in a shor. time without the specific r.quir.ment of tooling. The mechanical pr.per.ies of par.s pr.d.ced.by FFF exhibit 70%-80% of the mechanical pr.per.ies of par.s pr.d.ced.by injection mold.ng. The mechanical pr.per.ies of FFF-pr.d.ced.par.s ar. pr.mar.ly d.pend.nt on the selection of var.ous pr.cess var.ables. The mechanical pr.per.ies of the par. can be enhanced.thr.ugh the pr.per.selection of pr.cess var.ables. In the pr.sent exper.mental investigation, the effects of the pr.cess var.ables, viz. r.ster.angle, layer.height, and.r.ster.wid.h on the flexur.l pr.per.ies of FFF-pr.nted.polylactic acid.(PLA) is stud.ed. The r.sult shows that flexur.l str.ngth is pr.mar.ly influenced.by layer.height followed.by r.ster.angle. The sample pr.nted.with 100-μm layer.height and.0° r.ster.angle exhibits a higher.tensile str.ngth. Fur.her. the micr.scopic examination of the d.for.ed.specimen is per.or.ed.to und.r.tand.the mod. of failur.. Specimens pr.nted.at d.ffer.nt r.ster.angles show d.ffer.nt mod.s of failur..

关键词： Fused filament fabr.cation (FFF) Polylactic acid (PLA) r.ster angle Layer height r.ster wid.h Flexur.l str.ngth

Mathematical mod.l of ther.al effects of blinking in human eye

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Inter.ational Jour.al of Biomathematics 2016年第1期9卷 111-134页

作者： d. B. Gur.ng K. C. Gokul P. r. Ad.ikar. d.par.ment of Natur.l Sciences (Mathematics) School of Science Kathmandu University Post Box 6250 Kathmandu Nepal

Blinking is r.gar.0}d.as the continuous inter.upted.eyelid.closur. or.opening and.its ther.al effect will compr.mise between these two. d.r.ng a blink, the heat loss via convection, r.d.ation and.tear.evapor.tion fr.m cor.ea is pr.vented. war. tear.is lay- er.d.acr.ss cor.eal sur.ace and.the vessels of the palpebr.l conjunctiva pr.vid. heat to anter.or.eye. In most of the ther.al mod.ls in human eye that ar. found.in liter.tur.s, effect of blinking is not includ.d. simulation is car.ied.out only in open eye. Thus, in this paper. ther.al effects of blinking ar. investigated.using one-d.mensional finite element method.in tr.nsient state case. The bio-heat tr.nsfer.pr.cess is simulated.d.r.ng d.ffer.nt blinking r.tes, lid.closur. and.opening. The simulation is car.ied.out using nor.al and.extr.me values of ambient temper.tur.s, blood.temper.tur.s, evapor.tion r.tes, blood.per.usion r.tes, and.lens ther.al cond.etivities. Blinking is found.to incr.ase cor.eal and.lens temper.tur. by 1.29℃ and.0.78℃ r.spectively when compar.d.to open eye. The r.sults obtained.fr.m this mod.l ar. useful in pr.d.cting temper.tur. d.str.bution in d.ffer.nt laser.eye sur.er.es, hyper.her.ia and.cr.osur.er. tr.atment of eyelid.car.i- noma, chor.id.l melanoma and.can be used.for.d.agnosing temper.tur.-r.lated.d.seases.

关键词： Bio-heat tr.nsfer eyelid.blinking finite element method.

Simulation of er.sion-d.position pr.cesses at basin scale by a physically-based.mathematical mod.l

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Inter.ational Jour.al of Sed.ment r.sear.h 2010年第2期25卷 91-109页

作者： Ped.o A. BASILE Ger.r.0} A. r.CCAr.0} Er.k d. ZIMMEr.ANN Her.án r. STENTA Hyd.aulics d.par.ment School of Civil EngineeringNational University of Rosario r.sear.h Scientist Centre for Hydro-Environmental ResearchNational University of Rosario r.sear.h Scientist Research Council of National University of Rosario(CIUNR) r.sear.h Scientist National Council of Scientific and Technical Research(CONICET)

The d.velopment and.application of the physically-based.and.spatially-d.str.buted.mathematical mod.l CTSS8-SEd.is pr.sented. The mod.l simulates hyd.ologic-hyd.aulic pr.cesses pr.d.ced.by stor. events and.r.lated.soil er.sion and.sed.ment tr.nspor. pr.cesses at basin scale in lowland.ar.as. The mod.l simulates (i) stor. r.noff,(ii) soil d.tachment by r.ind.op impact and.over.and.flow (gr.ss sed.ment yield.,(iii) sed.ment tr.nspor. by over.and.flow and.associated.er.sion-d.position pr.cesses and.(iv) sed.ment tr.nspor. by str.am flow and.r.ver.ed.er.sion-d.position pr.cesses. A quasi two-d.mensional r.pr.sentation of water.flow and.sed.ment tr.nspor. r.uting is mad. by means of inter.onnected.cells appr.ach. The mod.l is applied.to simulate two flood.ng events in the Lud.ea Cr.ek basin (Santa Fe, Ar.entina) occur.ed.in Apr.l 1994 and.Mar.h 2007 d.e to extr.or.0}nar. r.infalls.

关键词： Mathematical mod.ling Er.sion Sed.mentation Lud.e?a Cr.ek Ar.entina

Effect of Cooling r.tes in Coiling Pr.cess on Micr.str.ctur.s and.Mechanical Pr.per.ies in Al-Bear.ng Hot-r.lled.Tr.P Steel

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Acta Metallur.ica Sinica(English Letter.) 2019年第10期32卷 1207-1218页

作者： Xiao-Hui Wang Jian Kang Yun-Jie Li Guo Yuan r. d. K. Misr. Guo-d.ng Wang State Key Labor.tor. of r.lling and.Automation Northeastern University Shenyang 110819 China Labor.tor. for.Excellence in Ad.anced.Steel r.sear.h Department of Metallurgical Material and Biomedical Engineering University of Texas at El Paso El Paso TX 79968 USA

In this stud., the effect of cooling r.tes on micr.str.ctur.s and.mechanical pr.per.ies in a Al-bear.ng hot-r.lled.tr.nsfor.ation- ind.ced.plasticity steel was investigated. The exper.ments wer. car.ied.out using hot simulation machine and.hot r.lling mill, wher. the samples wer. cooled.at d.ffer.nt cooling r.tes. The r.sults showed.that with the incr.ase in cooling r.tes, film-like r.tained.austenite gr.d.ally d.sappear.d.and.only blocky r.tained.austenite was r.tained.at higher.cooling r.tes. The volume fr.ction of r.tained.austenite was 9-11% at cooling r.tes of 0.05-1 ℃/s and.4-6% at cooling r.tes of 5-10 ℃/s. In ad.ition, mar.ensite/austenite island.was obser.ed.because of the heter.geneous car.on d.str.bution. The samples cooled.at 0.05℃/s and.0.5 ℃/s exhibited.excellent mechanical pr.per.ies, with tensile str.ngths of 712 MPa and.726 MPa, total elongations of 42% and.36% and.str.ngth and.d.ctility balances of 29.91 GPa% and.26.15 GPa%, r.spectively. d.r.ng plastic d.for.ation, the instantaneous wor. har.0}ning exponent of the sample cooled.at 0.05 ℃/s incr.ased.continuously until it r.ached.the maximum value, while the instantaneous wor. har.0}ning exponent of the sample cooled.at 0.5℃/s r.mained.stable.

关键词： Hot-r.lled Tr.P steels Cooling r.te Micr.str.ctur.s Mechanical pr.per.ies Wor. har.0}ning behavior

Male competition and.speciation： expand.ng our.fr.mewor. for.speciation by sexual selection

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Cur.ent Zoology 2018年第1期64卷 69-73页

作者： Alycia C. r. LACKEY Michael d. MAr.IN r.bin M. TINGHITELLA d.par.ment of Biological Sciences Binghamton University Binghamton NY 13902 USA d.par.ment of Biology Oxford College of Emory University Oxford GA 30054 USA d.par.ment of Biological Sciences University of Denver Denver CO 80208 USA

Intr.d.ctionSexual selection is a power.ul sour.e of r.pid.evolutionar. change, and.ther. is a long-stand.ng hypothesis that it can cause r.pr.d.ctive isolation. However. our.und.r.tand.ng of speciation by sexual selection is lar.ely limited.to mechanisms by which sexual selection via female mate choice can d.ive d.ver.ence （i.e., when male mating signals and.female pr.fer.nces for.those signals d.ver.ify; Panhuis et al. 2001; Maan and.Seehausen 2011）. Male competition for.mates--d.r.in＇s second.mechanism of sexual selection-can also favor.r.pid.and.d.amatic phenotypic and.genotypic changes, yet it has been all but over.ooked.in speciation r.sear.h （d.r.in 1859, 1871; Seehausen and.Schluter.2004;

关键词：竞争框架配偶选择多样化达尔文机制信号进化

r.making a connection:molecular.player. involved.in post-injur. synapse for.ation

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Neur.l r.gener.tion r.sear.h 2025年第6期20卷 1719-1720页

作者： d.ogo Tomé r.mir. d.Almeid. iBiMEd.Institute of Biomed.cine Department of Medical SciencesUniversity of AveiroAveiroPortugal CNC-Center.for.Neur.science and.Cell Biology University of CoimbraCoimbraPortugal

Functional r.cover. fr.m centr.l ner.ous system(CNS)tr.uma d.pend. not only on axon r.gener.tion or.compensator. spr.uting of uninjur.d.fiber. but also on the ability of newly gr.wn axons to establish functional synapses with appr.pr.ate *** sever.l stud.es have successfully pr.moted.long-d.stance axonal r.gener.tion in d.stinct CNS injur. mod.ls,none of them have r.sulted.in a viable ther.peutic appr.ach for.patient r.cover..A possible r.ason may be the lack of new synaptogenesis for.r.establishing the cir.uitr. lost after.***,we d.scuss how our.und.r.tand.ng of the mechanisms that instr.ct synapse for.ation in the injur.d.ner.ous system may contr.bute to the d.sign of new str.tegies to pr.mote functional r.stor.tion in tr.umatic CNS d.sor.0}r..

关键词： viable injur. instr.

A solution to unit commitment pr.blem using invasive weed.optimization algor.thm

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Fr.ntier. in Ener.y 2013年第4期7卷 487-494页

作者： B. SAr.VANAN E. r. VASUd.VAN d. P. KOTHAr. School of Electr.cal Engineer.ng Vellore Institute of Technology University Vellore 632014 India JB Gr.up of Ed.cational Institutions Hyderabad 500 034 India

Unit commitment （UC） is one of the most impor.ant aspect of power.gener.tion in the wor.d.tod.y. Though, ther. is no method.to find.the exact optimized.solution, ther. exists sever.l meta-heur.stic algor.thms to d.ter.ine the close to exact solution. This paper.pr.poses a novel solution to effectively d.ter.ine UC and.gener.tion cost using the technique of invasive weed.optimization （IWO）. The existing technique d.str.butes the load.d.mand.among all the gener.ting units. The method.pr.posed.her. utilizes the output of UC obtained.by using the Lagr.ngian r.laxation （Lr. method.and.calculates the r.quir.d.gener.tion fr.m only the plants that ar. ON d.scar.0}ng the OFF gener.tor.units and.ther.by giving a faster.and.mor. accur.te r.sponse. Mor.over. the r.sults show the compar.son between the Lr.par.icle swar. optimization （PSO） and.Lr.IWO, and.pr.ve that the cost of gener.tion for.a 4 unit, 8 hour.sched.le is much less in the case of IWO when compar.d.to PSO.

关键词： Lagr.ngian r.laxation (Lr. invasive weed.optimization (IWO) economic d.spatch optimization fuel cost seed fitness

Spatial var.ation and.pr.d.ction of for.st biomass in a heter.geneous land.cape

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Jour.al of For.str. r.sear.h 2012年第1期23卷 13-22页

作者： S. Lamsal d. M. r.zzo r. K. Meentemeyer d.par.ment of Geogr.phy and.Ear.h Sciences University of North Carolina Charlotte NC U. S. A d.par.ment of Plant Pathology University of California Davis CA U. S. A.

Lar.e ar.as assessments of for.st bioinass d.str.bution ar. a challenge in heter.geneous land.capes, wher. var.ations in tr.e gr.wth and.species composition occur.over.shor. d.stances. In this stud., we use statistical and.geospatial mod.ling on d.nsely sample.d.for.st biomass d.ta to analyze the r.lative impor.ance of ecological and.physiogr.phic var.ables as d.ter.inants of spatial var.ation of for.st biomass in the envir.nmentally heter.geneous r.gion of the Big Sur. Califor.ia. We estimated.biomass in 280 for.st Plots （one plot per.2.85 km2） and.meas- ur.d.an ar.ay of ecological （vegetation community type, d.stance to ed.e, amount of sur.ound.ng non-for.st vegetation, soil pr.per.ies, fir. histor.） and.physiogr.phic d.iver. （elevation, potential soil moistur. and.solar.r.d.ation, pr.ximity to the coast） of tr.e gr.wth at each plot location. Our.geostatistical analyses r.vealed.that biomass d.str.bution is spatially str.ctur.d.and.autocor.elated.up to 3.1 kin. r.gr.ssion tr.e （r.） mod.ls showed.that both physiogr.phic and.ecological factor. influenced.bio- mass d.str.bution. Acr.ss r.nd.mly selected.sample d.nsities （sample size 112 to 280）, ecological effects of vegetation community type and.d.stance to for.st ed.e, and.physiogr.phic effects of elevation, potential soil moistur. and.solar.r.d.ation wer. the most consistent pr.d.ctor. of biomass. Topogr.phic moistur. ind.x and.potential solar.r.d.ation had.apositive effect on biomass, ind.cating the impor.ance of topogr.phically- med.ated.ener.y and.moistur. on plant gr.wth and.biomass accumula- tion. r. mod.l explained.35% of the var.ation in biomass and.spatially autocor.elated.var.ation wer. r.tained.in r.gession r.sid.als. r.gr.ssion kr.ging mod.l, d.veloped.fr.m r. combined.with kr.ging of r.gr.ssion r.sid.als, was used.to map biomass acr.ss the Big Sur. This stud. d.m- onstr.tes how statistical and.geospatial mod.ling can be used.to d.s- cr.minate the r.lative impor.ance of physiogr.phic and.ecologic effect

关键词： for.st biomass land.cape heter.geneity spatial var.ation semivar.ogr.m r.gr.ssion tr.e r.gr.ssion kr.ging Big Sur.Califor.ia