Numerical Simulation of Unsteady Flow Around Forward Flight Helicopter with Coaxial Rotors.docx
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Numerical Simulation of Unsteady Flow Around Forward Flight Helicopter with Coaxial Rotors.docx
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NumericalSimulationofUnsteadyFlowAroundForwardFlightHelicopterwithCoaxialRotors
Lateralflightcontroldesignforahighlyflexibleaircraftusingnonsmoothoptimization OriginalResearchArticle
AerospaceScienceandTechnology,Volume15,Issue4,June2011,Pages314-322
A.M.Simões,P.Apkarian,D.Alazard,D.Noll
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AbstractAbstract|Figures/TablesFigures/Tables|ReferencesReferences
Abstract
Thispaperdescribesanonsmoothoptimizationtechniqueallowingtodesignalateralflightcontrollawforahighlyflexibleaircraft.Flexiblemodesandhigh-dimensionalmodelsposeamajorchallengetomoderncontroldesigntools.Itisshownthatthenonsmoothapproachofferspotentandflexiblealternativesinthisdifficultcontext.Morespecifically,theproposedtechniqueisusedtoachieveamixoffrequencydomainaswellastime-domainrequirementsforasetofdifferentloadconditions.
ArticleOutline
1.Introduction
2.Multi-objectivecontrollerdesignvianonsmoothoptimization
3.Nonsmoothoptimizationtechnique
4.Applicationtolateralflightcontroldesignofahighlyflexibleaircraft
4.1.Problemdescription
4.2.Nonsmoothsynthesis
5.Conclusion
Acknowledgements
References
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78
Effectsofaircraftnoiseandspeechonprosememory:
Whatroleforworkingmemorycapacity?
OriginalResearchArticle
JournalofEnvironmentalPsychology,Volume30,Issue1,March2010,Pages112-118
PatrikSörqvist
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Abstract
Previousresearchindicatesthataircraftnoiseandmeaningfulbackgroundspeechareparticularlydetrimentaltoschooladolescents'abilitytorememberwhattheyread,butuntilnowtheeffectsfromaircraftnoiseandspeechhaveneverbeencompareddirectlyinanexperiment.Furthermore,individualdifferencesinsusceptibilitytotheseeffectsarenotwellunderstood.Thepresentinvestigationaddressedthesetwoissues.Adolescentsattendinguppersecondaryschoolwererecruitedasparticipantsandthedatacollectionwasmadeintheirordinaryclassrooms.Theresultsfromtwoexperimentsrevealedthatspeechismoredetrimentaltoprosememorythanisaircraftnoise,andindividualdifferencesinworkingmemorycapacitycontributesmoretoindividualdifferencesinsusceptibilitytotheeffectsofaircraftnoiseonprosememorythantotheeffectsofspeech.Someappliedimplicationsofthosefindingstonoiseabatementinterventionsaresuggested.
ArticleOutline
1.Introduction
1.1.Experiment1–2
2.Experiment1a
2.1.Method
2.1.1.Participants
2.1.2.Aircraftnoise
2.1.3.Tasks
2.1.3.1.Operationspan
2.1.3.2.Prosememory
2.1.4.Procedure
2.2.Resultsanddiscussion
3.Experiment1b
3.1.Method
3.1.1.Participants
3.1.2.Materialsandprocedure
3.2.Resultsanddiscussion
4.Experiment2
4.1.Method
4.1.1.Participants
4.1.2.Materialsandprocedure
4.2.Resultsanddiscussion
5.Generaldiscussion
Acknowledgements
References
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79
Defecttoleranceassessmentofahelicoptercomponentsubjectedtomultiaxialload OriginalResearchArticle
EngineeringFractureMechanics,Volume77,Issue13,September2010,Pages2479-2490
M.Giglio,S.Beretta,U.Mariani,G.Ratti
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Abstract
Inthispaperasimplebuteffectivemethodologyforthedefecttolerantassessmentofastructuralcomponentispresented.Themethodologyisbasedontheexperimentalevidencesavailableinliteraturethatatthefatiguelimitnon-propagatingcracksareobservedneardefectspresentinthemetallicmaterial.Theevaluationofthethresholdstressintensityrangeoftheseshortcracksallowstocalculateasafetyfactorwithrespecttotheirpropagation.Themethodologyisappliedtothetailrotorhubofahelicopter.Thecomplexgeometryandloadconditionsmakethiscomponentveryinterestingforthedefecttoleranceassessment.Theapplicationtoanengineeringproblemallowstodescribethedifficultiesthatariseinthisprocessandtoshowthepossiblesolutionsthatcanbeadopted.
ArticleOutline
Nomenclature
1.Introduction
2.Theoreticalbackground
2.1.ΔKevaluation
2.2.ΔKthevaluation
2.3.ApplicationofthemodeltoTi–6Al–4Valloy
3.Defecttolerantassessment
3.1.Descriptionofthetailrotorhub
3.2.FEmodelofthetailrotorhub
3.3.ExperimentalvalidationoftheFEmodel
3.4.Selectionoftheassessmentzones
3.5.Evaluationofthestresscycleforanassessmentpoint
4.Resultsandconclusions
References
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NumericalSimulationofUnsteadyFlowAroundForwardFlightHelicopterwithCoaxialRotors OriginalResearchArticle
ChineseJournalofAeronautics,Volume24,Issue1,February2011,Pages1-7
HeyongXU,ZhengyinYE
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AbstractAbstract|ReferencesReferences
Abstract
Three-dimensionalunsteadyEulerequationsarenumericallysolvedtosimulatetheunsteadyflowsaroundforwardflighthelicopterwithcoaxialrotorsbasedonunstructureddynamicoversetgrids.Theperformancesofthetwocoaxialrotorsbothbecomeworsebecauseoftheaerodynamicinteractionbetweenthem,andtheinfluenceofthetoprotoronthebottomrotorisgreaterthanthatofthebottomrotoronthetoprotor.Thedownwashvelocityatthebottomrotorplaneismuchlargerthanthatatthetoprotorplane,andthedownwashvelocityatthetoprotorplaneisalittlelargerthanthatatanindividualrotorplane.Thedownwashvelocityandthrustcoefficientbothbecomelargerwhenthecollectiveangleofbladesisadded.Whenthespacingbetweenthetwocoaxialrotorsincreases,thethrustcoefficientofthetoprotorincreases,butthetotalthrustcoefficientreducesalittle,becausethedecreaseofthebottomrotorthrustcoefficientislargerthantheincreaseofthetoprotorthrustcoefficient.
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‘Physicianstoadyingplanet’:
HelenCaldicott,RandallForsberg,andtheanti-nuclearweaponsmovementoftheearly1980s OriginalResearchArticle
TheLeadershipQuarterly,Volume21,Issue2,April2010,Pages278-291
BenjaminRedekop
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AbstractAbstract|ReferencesReferences
Abstract
Thisarticleprofilestwoimportantleadersoftheanti-nuclearweaponsmovementintheUnitedStatesduringtheearly1980s.HelenCaldicottandRandallForsbergwerevisionary,transformationalleaderswhocrossedavarietyofboundariesforthecommongood,andassuchareprimeexemplarsofintegrativeleadershipinaction.Caldicottwasacharismaticfigurewhousedherstatusasphysicianandmothertorallyaworldwidemovementopposedtotheongoingproliferationofnuclearweaponsandtalkof“winnable”nuclearwar.Forsbergwasthemainarchitectofthenuclear“Freeze”campaignwhosehumanitarianvisionandcommon-senseapproachtopoliticalactionhelpedunitediversesegmentsoftheAmericanpublicaroundtheFreezeproposalandpushtheReaganadministrationtowardsdisarmamenttalkswiththeSovietUnion.Thearticleanalyzestheleadershipofbothwomeninhistoricalandsocial–scientificcontext,sheddinglightontworelativelyunknown—yetimportant—socialmovementleaderswhosestorieshavemuchtotellusaboutintegrativepublicleadership,thechallengesfacedbywomenleaders,andthestrengthsandpitfallsofcharismaticleadership.
ArticleOutline
1.Introduction
2.Growingconcern
3.Acalltohaltthearmsrace
4.Avisionaryleader
5.HelenCaldicott:
Adesperatepassion
6.Afrighteningmessage
7.Charisma
8.ResignationfromPSR
9.Conclusion:
Integrativepublicleaderscrossingboundariesforthecommongood
References
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Carbonemissionsfrominternationalcruiseshippassengers’traveltoandfromNewZealand OriginalResearchArticle
EnergyPolicy,Volume38,Issue5,May2010,Pages2552-2560
OliverJ.A.Howitt,VincentG.N.Revol,IngaJ.Smith,CraigJ.Rodger
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Abstract
Greenhousegasemissionsfrominternationaltransportcontributetoanthropogenicglobalwarming,yettheseemissionsarenotliableundertheKyotoProtocol.Internationalattentionisbeinggiventoquantifyingsuchemissions.ThispaperpresentstheresultsofresearchintointernationalcruiseshipjourneystoandfromNewZealand.CO2emissionsfromsuchjourneyswerecalculatedusinganactivitybased,or“bottom-up”,model.EmissionsfactorsforindividualjourneysbycruiseshipstoorfromNewZealandin2007rangedbetween250and2200 gofCO2perpassenger-kilometre(g CO2perp-km),withaweightedmeanof390 gCO2perp-km.Theweightedmeanenergyuseperpassengernightforthe“hotel”functionofthesecruisevesselswasestimatedas1600 MJpervisitornight,12timeslargerthanthevalueforaland-basedhotel.Usingasimplepriceelasticitiescalculation,internationalcruisejourneysfortransportpurposeswerefoundtohaveagreaterrelativedecreaseindemandthanplanejourneyswhentheimpactofcarbonpricingwasanalysed.ThepotentialtodecreasetheCO2emissionsperp-kmwasexamined,andifpassengeraccommodationwascompactedandsomeluxuryamenitiesdispensedwithvaluessimi
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