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计算机有关论文范例,与硕士学位文重复率武汉相关论文格式模板
本论文是一篇计算机有关论文格式模板,关于硕士学位文重复率武汉相关电大毕业论文范文。免费优秀的关于计算机及算法及试题方面论文范文资料,适合计算机论文写作的大学硕士及本科毕业论文开题报告范文和学术职称论文参考文献下载。
goexaminingaBasilosaurus:Basilosaurus
TheBasilosauruswasquiteaprototypeofawhale.Itwasabout15meterslongfor5tons.Itstillhadaquasi-independentheadandposteriorpaws.Hemovedusingundulatorymovementsandhuntedsmallpreys.Itsanteriormemberswerereducedtosmallflipperswithanelbowarticulation.
Movementsinsuchaviscouselement(water)areveryhardandrequirebigefforts.Peopleconcernedmusthaveenoughenergytomoveandcontrolitstrajectory.Theanteriormembersofbasilosauruswerenotreallyadaptedtoswimming.Toadaptthem,adoublephenomenonmustoccur:theshorteningofthe"arm"withthelockingoftheelbowarticulationandtheextensionofthefingerswhichwillconstitutethebasestructureoftheflipper.
Tursiopsflipper
Theimageshowsthattwofingersofthemondolphinarehypertrophiedtothedetrimentoftherestofthemember.
Thebasilosauruswasahunter,hehadtobefastandprecise.Throughtime,subjectsappearedwithlongerfingersandshortarms.Theycouldmovefasterandmorepreciselythanbefore,an
计算机有关论文范例
Meanwhile,otherimprovementsoccurredconcerningthegeneralaerodynamicliketheintegrationoftheheadtothebody,improvementoftheprofile,strengtheningofthecaudalfin...finallyproducingasubjectperfectlyadaptedtotheconstraintsofanaqueousenvironment.
Thisprocessofadaptation,thismorphologicaloptimizationissoperfectthatnowadays,thesimilaritybetweenashark,adolphinorasubmarineisstriking.Butthefirstisacartilaginousfish(Chondrichtyen)originatingintheDevonian(-400millionyears),longbeforetheapparitionofthefirstmammalwhoseCetaceandescendfrom.
Darwinianmechanismhencegenerateanoptimizationprocess6,Hydrodynamicoptimizationforfishesandothersmarineanimals,aerodynamicforpterodactyls,birdsorbats.Thisobservationisthebasisofgeicalgorithms.
B-EvolutionandGeicAlgorithms
JohnHolland,fromtheUniversityofMichiganbeganhisworkongeicalgorithmsatthebeginningofthe60s.AfirstachievementwasthepublicationofAdaptationinNaturalandArtificialSystem7in1975.
Hollandhadadoubleaim:toimprovetheunderstandingofnaturaladaptationprocess,andtodesignartificialsystemshavingpropertiessimilartonaturalsystems.
Thebasicideaisasfollow:thegeicpoolofagivenpopulationpotentiallycontainsthesolution,orabettersolution,toagivenadaptiveproblem.Thissolutionisnot"active"becausethegeicbinationonwhichitreliesissplitbetweenseveralsubjects.Onlytheassociationofdifferentgenomescanleadtothesolution.Simplisticallyspeaking,wecouldbyexampleconsiderthattheshorteningofthepawandtheextensionofthefingersofourbasilosaurusarecontrolledby2"genes".Nosubjecthassuchagenome,butduringreproductionandcrossover,newgeicbinationoccurand,finally,asubjectcaninherita"goodgene"frombothparents:hispawisnowaflipper.
Hollandmethodisespeciallyeffectivebecausehenotonlyconsideredtheroleofmutation(mutationsimproveveryseldomthealgorithms),buthealsoutilizedgeicrebination,(crossover):theserebination,thecrossoverofpartialsolutionsgreatlyimprovethecapabilityofthealgorithmtoapproach,andeventuallyfind,theoptimum.
C-FunctioningofaGeicAlgorithm
Asanexample,we'regoingtoenteraworldofsimplifiedgeic.The"chromosomes"encodeagroupoflinkedfeatures."Genes"encodetheactivationordeactivationofafeature.
Letusexaminetheglobalgeicpooloffourbasilosaurusbelongingtothisworld.Wewillconsiderthe"chromosomes"whichencodethelengthofanteriormembers.Thelengthofthe"paw"andthelengthofthe"fingers"areencodedbyfourgenes:thefirsttwoencodethe"paw"andtheothertwoencodethefingers.
Inourrepresentationofthegenome,thecircleonbluebackgrounddepicttheactivationofafeature,thecrossongreenbackgrounddepictitsdeactivation.Theidealgenome(shortpawsandlongfingers)is:.
Thegeicpoolofourpopulationisthefollowingone:
SubjectGenomeABCDWecannoticethatAandBaretheclosesttotheirancestors,they'vegotquitelongpawsandshortfingers.Onthecontrary,Disclosetotheoptimum,hejustneedsasmalllengtheningofhisfingers.
Thisissuchapeculiarworldthattheabilitytomoveisthemaincriteriaofsurvivalandreproduction.NofemalewouldeasilyaccepttomarrybasilosauruswhosepawswouldlooklikeA's.ButtheyalldreamtomeetDoneday.
Thefitnessiseasytopute:wejusthavetogiveonepointtoeachgenecorrespondingtotheideal.Theperfectgenomewillthengetfourpoints.Theprobabilityofreproductionofagivensubjectwilldirectlydependonthisvalue.Inourcase,we'llgetthefollowingresults:
SubjectFitnessReproductionprobabilityA11/7等于0.143B11/7等于0.143C22/7等于0.286D33/7等于0.428Total77/7等于1We'llconsideracycleofreproductionwithfordescendants,i.e.fourmatingconcerningheightsubjects.Dwillbeselectedfourtimesandwillthengetfourdescendants.Cwillbeselectedtwiceandwillgettwodescendants.FinallyAandBwillonlybeselectedonce.
Thereproductionpatternisthefollowing:
SubjectReceivedgenesGenomeFitnessReproductionprobabilityA'A:D:22/10等于0.2B'B:D:22/10等于0.2C'D:C:33/10等于0.3D'C
计算机有关论文范例,与硕士学位文重复率武汉相关论文格式模板参考文献资料：