Magnetic bearingsa new world opens for design engineers.docx
《Magnetic bearingsa new world opens for design engineers.docx》由会员分享,可在线阅读,更多相关《Magnetic bearingsa new world opens for design engineers.docx(30页珍藏版)》请在冰豆网上搜索。
![Magnetic bearingsa new world opens for design engineers.docx](https://file1.bdocx.com/fileroot1/2023-2/6/c18b8f24-1261-44b6-836b-ee03becc60f2/c18b8f24-1261-44b6-836b-ee03becc60f21.gif)
Magneticbearingsanewworldopensfordesignengineers
ComputerPhysicsCommunications,Volume181,Issue6,June2010,Pages1150-1160
BenzhuoLu,XiaolinCheng,JingfangHuang,J.AndrewMcCammon
Showpreview | Relatedarticles | Relatedreferenceworkarticles
Purchase
$31.50
489
Servicecategory-to-wavelengthselectiontechniqueforQoSsupportinconnection-orientedopticalpacketswitching OriginalResearchArticle
ComputerNetworks,Volume51,Issue1,17January2007,Pages14-30
D.Careglio,J.SoléPareta,S.Spadaro
Closepreview | Relatedarticles | Relatedreferenceworkarticles
AbstractAbstract|Figures/TablesFigures/Tables|ReferencesReferences
Abstract
Thispaperconsidersanopticalpacket-switchednodesubjecttoasynchronous,variable-lengthpacketsandconnection-orientedoperation.Wefirstlyaddresstheproblemofsettinguptheopticalvirtualconnectionsandproperlyconfiguringtheforwardingtableatthenode.Wedonotdealwithroutingaspects,butwiththeefficientmappingofthevirtualconnectionstothewavelengthsoftheoutputports.Inthiscontext,wesuggestawavelengthassignmentprocedurethatimprovesthenodeperformanceincomparisonwithsimplerandomorbalancedschemes.WethenaddresstheQoSprovisioningproblem.Whileexistingsolutionsfocusonapplyingsomeformsofresourcereservationontopofthecontentionresolutionalgorithm,hereweproposeamethodbasedonthewell-knownATMschemeofdefiningdifferentservicecategories.Inparticular,wedefineacasestudywiththreeOPSservicecategories,andforeachcategoryaspecificcontentionresolutionalgorithmisapplied.Withsuchastrategythealgorithmspresenttheproblemofadifferentperformancealignment;wesolveitbydesigninganadhocopticalbufferarchitecturebasedonnon-degeneratedelays.Theperformanceofthefinalnodearchitectureisevaluatedbysimulation.Theresultsobtainedindicatethemeritsofthismethod,whichopensupinterestingfuturedevelopmentsforawholeopticalnetworkscenario.
ArticleOutline
1.Introduction
2.TheWAprobleminconnection-orientedOPS
2.1.Problemdescription
2.2.Thegroupingwavelengthassignment(GRP-WA)algorithm
2.3.Performanceevaluation
3.QoSprovisioning
3.1.Servicecategory-to-wavelengthselectiontechnique
3.2.Performanceevaluation
3.3.Adhocopticalbufferarchitecture
4.Summaryandconclusion
Acknowledgements
AppendixA.Simulationenvironment
References
Vitae
Purchase
$31.50
490
Thedeploymentofartificialreefecosystem:
Modelling,simulationandapplication OriginalResearchArticle
SimulationModellingPracticeandTheory,Volume14,Issue5,July2006,Pages663-675
Chun-HsiungLan,Che-YuHsui
Closepreview | Relatedarticles | Relatedreferenceworkarticles
AbstractAbstract|Figures/TablesFigures/Tables|ReferencesReferences
Abstract
Artificialreefs(ARs)havebeendemonstratedtobeapotentialtoolfortherestorationofmarinehabitatandtoretardthestressofcoralreefsinrecentdecades.Formostengineers,thedeploymentofanartificialreefecosystem(ARE)isbasedontheirexperience,butwhatistheeffectivedeploymenttoproducethehigherabundanceandtoenrichbiomassunderthefinitebudgetisseldommentioned.Infact,howtodeployartificialreefsintotheselectedsiteandconstructaneffectiveAREisthemostchallengetoecologicalengineers.
Themainobjectiveofthisresearchistoconstructamathematicalmodelcalledthedeploymentofartificialreefcommunities(DARCs)model,andthentoprovideaconcreteapproachfordeployinganAREunderthefinitebudget.TheconstructingspiritofDARCsmodelisbasedontheobservationsofbiologiststhatahighercomplexityofhabitatsystemwillincreasethespeciesdiversityandbiomass.Thefractaldimension(FD)isappliedasanassessingindicatorforthehabitatsystemcomplexityofAREinthisstudy.Inaddition,astep-by-stepalgorithmforachievingthemaximalfractaldimensionofanAREthroughthedeterminationsofthenumberofdeployedartificialreefcommunities(ARCs),thedistanceofadjacentARCs,andthespatialconfigurationofARCsinanAREispresented.AcomputerizedtoolwrittenbyFortranprogramtoconductthedesignofanAREaswellasperformthesimulatedanalysesiscompletelyproposed,andacasestudyisfollowed.Thesimulation-basedanalysesofchangingbudgetrevealthattheFDofagivenregionwillbeconstrainedregardlessofincreasingbudget.ThisphenomenonshowsthatthemoredeploymentofARCsmayleadtowastecapital.Finally,adecisionsupportsystemcalledDSSforAREisestablishedforthequick-designofanARecosystemundertheconsiderationofconservationpolicy.
ArticleOutline
Nomenclature
1.Introduction
2.Assumptions
3.Modelconstruction
4.Astep-by-stepalgorithm
5.Acasestudy
6.Simulatedanalyses
7.Decisionsupportsystem
8.Conclusion
Acknowledgements
AppendixA.Appendix
References
Purchase
$31.50
491
Non-linearaeroelasticpredictionforaircraftapplications ReviewArticle
ProgressinAerospaceSciences,Volume43,Issues4-6,May-August2007,Pages65-137
M.J.deC.Henshaw,K.J.Badcock,G.A.Vio,C.B.Allen,J.Chamberlain,I.Kaynes,G.Dimitriadis,J.E.Cooper,M.A.Woodgate,A.M.Rampurawala,D.Jones,C.Fenwick,A.L.Gaitonde,N.V.Taylor,D.S.Amor,T.A.Eccles,C.J.Denley
Closepreview | Relatedarticles | Relatedreferenceworkarticles
AbstractAbstract|Figures/TablesFigures/Tables|ReferencesReferences
Abstract
Currentindustrialpracticeforthepredictionandanalysisofflutterreliesheavilyonlinearmethodsandthishasledtooverlyconservativedesignandenveloperestrictionsforaircraft.Althoughthemethodshaveservedtheindustrywell,itisclearthatforanumberofreasonstheinclusionofnon-linearityinthemathematicalandcomputationalaeroelasticpredictiontoolsishighlydesirable.Theincreaseinavailableandaffordablecomputationalresources,togetherwithmajoradvancesinalgorithms,meanthatnon-linearaeroelastictoolsarenowviablewithintheaircraftdesignandqualificationenvironment.ThePartnershipforUnsteadyMethodsinAerodynamics(PUMA)DefenceandAerospaceResearchPartnership(DARP)wassponsoredin2002toconductresearchintonon-linearaeroelasticpredictionmethodsandanacademic,industry,andgovernmentconsortiumcollaboratedtoaddressthefollowingobjectives:
(1)Todevelopuseablemethodologiestomodelandpredictnon-linearaeroelasticbehaviourofcompleteaircraft.
(2)Toevaluatethemethodologiesonrealaircraftproblems.
(3)Toinvestigatetheeffectofnon-linearitiesonaeroelasticbehaviourandtodeterminewhichhavethegreatesteffectontheflutterqualificationprocess.Theseaimshavebeenveryeffectivelymetduringthecourseoftheprogrammeandtheresearchoutputsinclude:
(a)Newmethodsavailabletoindustryforuseintheflutterpredictionprocess,togetherwiththeappropriatecoachingofindustryengineers.
(b)Interestingresultsinbothlinearandnon-linearaeroelastics,withcomprehensivecomparisonofmethodsandapproachesforchallengingproblems.
(c)Additionalembryonictechniquesthat,withfurtherresearch,willfurtherimproveaeroelasticscapability.Thispaperdescribesthemethodsthathavebeendevelopedandhowtheyaredeployablewithintheindustrialenvironment.WepresentathoroughreviewofthePUMAaeroelasticsprogrammetogetherwithacomprehensivereviewoftherelevantresearchinthisdomain.ThisissetwithinthecontextofagenericindustrialprocessandtherequirementsofUKandUSaeroelasticqualification.Arangeoftestcases,fromsimplesmallDOFcasestofullaircraft,havebeenusedtoevaluateandvalidatethenon-linearmethodsdevelopedandtomakecomparisonwiththelinearmethodsineverydayuse.Thesehavefocusedmainlyonaerodynamicnon-linearity,althoughsomeresultsforstructuralnon-linearityarealsopresented.Thechallengesassociatedwithtimedomain(coupledcomputationalfluiddynamics–computationalstructuralmodel(CFD–CSM))methodshavebeenaddressedthroughthedevelopmentofgridmovement,fluid–structurecoupling,andcontrolsurfacemovementtechnologies.Conclusionsregardingtheaccuracyandcomputationalcostofthesearepresented.Thecomputationalcostoftime-domainmethods,despitesubstantialimprovementsinefficiency,remainshigh.However,significantadvanceshavebeenmadeinreducedordermethods,thatallownon-linearbehaviourtobemodelled,butatacostcomparablewiththatoftheregularlinearmethods.OfparticularnoteisamethodbasedonHopfbifurcationthathasreachedanappropriatematurityfordeploymentonrealaircraftconfigurations,thoughonlylimitedresultsarepresentedherein.ResultsarealsopresentedfordynamicallylinearisedCFDapproachesthatholdoutthepossibilityofnon-linearresultsatafractionofthecostoftimecoupledCFD–CSMmethods.Locallinearisationapproaches(higherorderharmonicbalanceandcontinuationmethod)arealsopresented;thesehavetheadvantagethatnopriorassumptionofthenatureoftheaeroelasticinstabilityisrequired,butcurrentlythesemethodsarelimitedtolowDOFproblemsanditisthoughtthatthesewillnotreachalevelofmaturityappropriatetorealaircraftproblemsforsomeyearstocome.Nevertheless,guidanceonthemostlikelyapproacheshasbeenderivedandthisformsthebasisforongoingresearch.Itisimportanttorecognisethattheaeroelasticdesignandqualificationrequiresavarietyofmethodsapplicableatdifferentstagesoftheprocess.Themethodsreportedhereinarema