简介：Wecomputethewakeofatwo-dimensionalandthree-dimensionalflexiblefininanunsteadyflowfieldwithheavingandpitchingmotionsusingFLUENT.Deflexionmodeisusedforanon-uniformcantileverbeamwithnon-uniformlydistributedload.Theeffectofchordwisedeflexionlengthonthecharacteristicsofpropulsionisdiscussedfortwo-dimensionalflexiblefin.Thethrustcoefficientdecreases,propulsiveefficiencyincreasesandtheintensityofturbulenceattenuatesgraduallyasthedeflexionlengthincreases.Forathree-dimensionalflexiblefin,theintensityofthevortexintheplaneofsymmetryishigherthanthatintheplaneat3/4spanlengthofthecaudalfin.Butthepropulsiveperformanceachievedisnotwhatweexpectedwiththegivendeflexionmode.

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简介：Syntheticdryadhesivesinspiredbythenano-andmicro-scalehairsfoundonthefeetofgeckosandsomespidershavebeendevelopedforalmostadecade.Elastomericsinglelevelmicro-scalemushroomshapedfibresarecurrentlyabletofunctionevenbetterthannaturaldryadhesivesonsmoothsurfacesundernormalloading.However,theadhesionofthesesinglelevelsyntheticdryadhesivesonroughsurfacesisstillnotoptimalbecauseofthereducedcontactsurfacearea.Innature,contactareaismaximizedbyhierarchicallystructuringdifferentscalesoffibrescapableofconformingsurfaceroughness.Inthispaper,weadaptthenature’ssolutionaridproposeanoveldual-levelhierarchicaladhesivedesignusingPolydimethylsiloxane(PDMS),whichistestedunderpeelloadingatdifferentorientations.Anegativemacro-scalemoldismanufacturedbyusingalasercuttertodefineholesinaPoly(methylmethacrylate)(PMMA)plate.AftercastingPDMSmacro-scalefibresbyusingtheobtainedPMMAmold,apreviouslypreparedmicro-fibreadhesiveisbondedtothemacro-scalefibresubstrate.Oncethebondingpolymeriscured,themicro-fibreadhesiveiscuttoformmacroscalemushroomcaps.Eachmacro-fibreoftheresultinghierarchicaladhesiveisabletoconformtoloadsappliedindifferentdirections.Thedual-levelstructureenhancesthepeelstrengthonsmoothsurfacescomparedtoasingle-leveldryadhesive,butalsoweakenstheshearstrengthoftheadhesiveforagivenareaincontact.Theadhesiveappearstobeveryperformancesensitivetothespecificsizeofthefibretips,andexperimentsindicatethatdesigninghierarchicalstructuresisnotassimpleasplacingmultiplescalesoffibresontopofoneanother,butcanrequiresignificantdesignoptimizationtoenhancethecontactmechanicsandadhesionstrength.

简介：AnewmethodforsimulatingthefoldingpathwayofRNAsecondarystructureusingthemodifiedantcolonyalgorithmisproposed.ForagivenRNAsequence,thesetofallpossiblestemsisobtainedandtheenergyofeachstemiscalculatedandstoredattheinitialstage.Furthermore,amorerealisticformulaisusedtocomputetheenergyofmulti-branchloopinthefollowingiteration.Thenafoldingpathwayissimulated,includingsuchprocessesasconstructionoftheheuristicinformation,theruleofinitializingthepheromone,themechanismofchoosingtheinitialandnextstemandthestrategyofupdatingthepheromonebetweentwodifferentstems.FinallybytestingRNAsequenceswithknownsecondarystructuresfromthepublicdatabases,weanalyzetheexperimentaldatatoselectappropriatevaluesforparameters.ThemeasureindexesshowthatourprocedureismoreconsistentwithphylogeneticallyprovenstructuresthansoftwareRNAstructuresometimesandmoreeffectivethanthestandardGeneticAlgorithm.

简介：Inthepost-genomicbiologyera,thereconstructionofgeneregulatorynetworksfrommicroarraygeneexpressiondataisveryimportanttounderstandtheunderlyingbiologicalsystem,andithasbeenachallengingtaskinbioinformatics.TheBayesiannetworkmodelhasbeenusedinreconstructingthegeneregulatorynetworkforitsadvantages,buthowtodeterminethenetworkstructureandparametersisstillimportanttobeexplored.Thispaperproposesatwo-stagestructurelearningalgorithmwhichintegratesimmuneevolutionalgorithmtobuildaBayesiannetwork.Thenewalgorithmisevaluatedwiththeuseofbothsimulatedandyeastcellcycledata.Theexperimentalresultsindicatethattheproposedalgorithmcanfindmanyoftheknownrealregulatoryrelationshipsfromliteratureandpredicttheothersunknownwithhighvalidityandaccuracy.

简介：ThispaperdemonstratestheapplicationofadesigntoolcalledBioTRIZ.Itsdevelopersclaimthatitcanbeusedtoaccessbiologicalstrategiesforsolvingengineeringproblems.Ouraimistodesignaroofforhotclimatesthatgetsfreecoolingthroughradiantcouplingwiththesky.Theinsulationinastandardroofstopsthesunandconvectionfromwarmingthethermalmass.Butitalsorestrictsthemass’slongwaveviewofthecoolsky.DifferentsolutionstothisconflictareofferedbyBioTRIZ.Thechosensolutionistoreplacethestandardinsulationcomponentwithanopencellhoneycomb.Theverticalcellswouldallowlongwaveradiationtopass,whilearrestingconvection.ThesolutionsofferedbyBioTRIZ’stechnologicalcounterpartincludenosuchchangesinstructure.Itisestimatedthatthethermalmassinthebiomimeticroofwouldremainonaverage4.5?CcoolerthaninastandardroofoverayearinRiyadh,SaudiArabia.