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簡(jiǎn)介：此文檔是畢業(yè)設(shè)計(jì)外文翻譯成品（含英文原文中文翻譯），無需調(diào)整復(fù)雜的格式下載之后直接可用，方便快捷本文價(jià)格不貴,也就幾十塊錢一輩子也就一次的事外文標(biāo)題INTRODUCTIONTOTHEDJANGOFRAMEWORK外文作者DANIELRUBIO文獻(xiàn)出處DANIELRUBIOINTRODUCTIONTOTHEDJANGOFRAMEWORKMBEGINNINGDJANGO2017129如覺得年份太老，可改為近2年，畢竟很多畢業(yè)生都這樣做英文8701單詞，40127字符，中文12987漢字。INTRODUCTIONTOTHEDJANGOFRAMEWORKDANIELRUBIOTHEDJANGOFRAMEWORKSTARTEDIN2003,ASAPROJECTDONEBYADRIANHOLOVATYANDSIMONWILLISONATTHEJOURNALWORLDNEWSPAPERINLAWRENCE,KANSAS,INTHEUNITEDSTATESIN2005,HOLOVATYANDWILLISONRELEASEDTHEFIRSTPUBLICVERSIONOFTHEFRAMEWORK,NAMINGITAFTERTHEBELGIANFRENCHGUITARISTDJANGOREINHARDTFASTFORWARDTO2017–THEDJANGOFRAMEWORKNOWOPERATESUNDERTHEGUIDANCEOFTHEDJANGOSOFTWAREFOUNDATIONDSF,THEFRAMEWORKCOREHASOVER1000CONTRIBUTORSWITHMORETHAN15RELEASEVERSIONS,ANDTHEREAREOVER3000PACKAGESSPECIFICALLYDESIGNEDTOWORKWITHTHEDJANGOFRAMEWORK1THEDJANGOFRAMEWORKHASREMAINEDTRUETOITSORIGINSASAMODELVIEWCONTROLLERTHEMOSTPRODUCTIVEFRAMEWORKSFORBUILDINGTHEFEATURESNEEDEDBYMOSTMEDIUMTOLARGEWEBAPPLICATIONSNOW,WHILEYOUMIGHTTHINKI’MBIASED–AFTERALLI’MWRITINGANENTIREBOOKABOUTTHETOPIC–I’LLLAYOUTTHESEDESIGNPRINCIPLESFIRST,SOYOUCANGAINABETTERUNDERSTANDINGOFWHATGIVESTHEDJANGOFRAMEWORKTHISEDGEDON’TREPEATYOURSELFDRYPRINCIPLEREPETITIONMIGHTBEGOODTOEMPHASIZEAPOINT,BUTWHENITCOMESTOWEBDEVELOPMENT,ITJUSTLEADSTOADDITIONALANDTIMECONSUMINGWORKINFACT,THEVERYNATUREOFWEBDEVELOPMENT,WHICHOPERATESACROSSMULTIPLETIERSINTERACTINGWITHONEANOTHEREG,HTMLTEMPLATES,BUSINESSLOGICMETHODS,ANDDATABASES,LENDSITSELFTOREPETITIONTHEDJANGOFRAMEWORKREALLYTRIESTOFORCEYOUNOTTOREPEATYOURSELF,SOLET’SSEEHOWDJANGOENFORCESNOTREPEATINGYOURSELFANDWHYTHISISAGOODTHINGLET’SSAYYOUWANTTOBUILDACOFFEEHOUSEAPPLICATIONTOPUBLISHINFORMATIONABOUTSTORESANDALSOHAVEACONTACTFORMFORCUSTOMERSTHEFIRSTTHINGYOU’LLNEEDTODOISDETERMINEWHATKINDOFINFORMATIONISREQUIREDFORSTORESANDTHECONTACTFORMFIGURE11ILLUSTRATESAMOCKUPOFTWODJANGOMODELSFOREACHOFTHESEENTITIESFIGURE11DJANGOMODELSFORSTOREANDCONTACTENTITIESNOTICEHOWTHEDJANGOMODELSINFIGURE11EACHHAVEDIFFERENTFIELDNAMESANDADATATYPETORESTRICTVALUESFOREXAMPLE,THESTATEMENTNAMEMODELSCHARFIELDMAX_LENGTH30TELLSDJANGOASTORENAMESHOULDHAVEAMAXIMUMOF30CHARACTERS,WHILETHESTATEMENTEMAILMODELSEMAILFIELDTELLSDJANGOTHECONTACTENTITYSHOULDCONTAINAVALIDEMAILVALUEIFTHECOFFEEHOUSEISLIKEMOSTWEBAPPLICATIONS,

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簡(jiǎn)介：STUDIESONELECTROLESSNICKEL–PTFECOMPOSITECOATINGSKNSRINIVASANANDSJOHNELECTROLESSDEPOSITIONOFNICKELBASEDCOMPOSITESPRODUCESOUTSTANDINGTRIBIOLOGICALBEHAVIOURTHESECOMPOSITECOATINGSAREFORMEDBYADDITIONTOTHEELECTROLESSNICKELSOLUTIONOFTHEMATERIALTOBECODEPOSITED,INPOWDERFORM,ANDBYMAINTAININGITINSUSPENSIONDURINGTHEDEPOSITIONPROCESSSOTHATITISINCORPORATEDINTOTHEDEPOSITTHEMOSTCOMMONLYUSEDHARDDISPERSEDCOMPOUNDSARESIC,DIAMONDPOWDER,ALUMINA,TIC,BN,CHROMIUMCARBIDEORWCRECENTLY,ELECTROLESSNICKELCONTAININGPTFEASACOMPOSITEMATERIALHASBEENUSEDBECAUSEITISUNIFORM,HIGHLYADHERENT,HARDWEARING,DRYLUBRICATING,NONGALLING,HASALOWERCOEFFICIENTOFFRICTIONANDGOODCORROSIONRESISTANCEPROPERTIESTHEPRESENTPAPERSTUDIESTHEEFFECTOFPTFEINANELECTROLESSNI–ACIDBATHONTHERATEOFDEPOSITION,INCORPORATIONOFPTFEANDPHOSPHOROUSCONTENTINTHEDEPOSIT,WEARANDCORROSIONRESISTANCEKEYWORDSELECTROLESSCOMPOSITES,CHEMICALDEPOSITION,NICKEL–PHOSPHOROUS–PTFECOMPOSITES,COMPOSITECOATINGINTRODUCTIONANELECTRODEPOSITEDCOMPOSITEPLATINGISAUNIFORMDISPERSIONOFSMALLDISCRETEPARTICULATEMATTERDELIBERATELYCODEPOSITEDWITHINAMETALLICCOATING1–3ELECTROLESSNICKELPHOSPHOROUSCOATINGSHAVEMANYPROPERTIESTHATARESUPERIORTOTHOSEOFELECTRODEPOSITEDNICKEL4BECAUSEOFTHEPHOSPHOROUSCONTENT,ELECTROLESSNICKELISHARDERANDHASBETTERCORROSIONRESISTANCE5ELECTROLESSNICKELCOMPOSITESCOMBINETHEUNIQUEPROPERTIESOFCONVENTIONALELECTROLESSNICKELDEPOSITSSUCHASUNIFORMITYOFDEPOSITIONOVERCOMPLEXGEOMETRIES,HIGHHARDNESSANDGOODCORROSIONRESISTANCEWITHTHATOFABRASIVEMATERIALSPOSSESSINGHIGHTEMPERATURERESISTANCEANDOTHERTRIBIOLOGICALPROPERTIESITISINTERESTINGTONOTETHATINELECTROLESSDEPOSITIONITISPOSSIBLETOACHIEVEAHIGHPERCENTAGEOFINCORPORATIONEVENATLOWCONCENTRATIONSOFPARTICLESINTHEBATH,INCONTRASTTOELECTROPLATING,WHEREALARGECONCENTRATIONOFPARTICLESMUSTBEPRESENTTOGETAHIGHPERCENTAGEOFINCORPORATIONINRECENTYEARS,COMPOSITEMATERIALSHAVEGAINEDIMPORTANCEINENGINEERINGINDUSTRIES,ESPECIALLYFORHIGHTECHNOLOGYAPPLICATIONSSUCHASAEROENGINES,MODERNGASTURBINEENGINES,AUTOMOBILES,ETC6INELECTROLESSCOMPOSITES,THEMATRIXISNOTPURENICKEL,BUTITCANBEEITHERNI–PORNI–B,DEPENDINGUPONTHENATUREOFTHEREDUCINGAGENTSUSEDINTHEBATHTHEMOSTCOMMONLYUSEDHARDDISPERSEDCOMPOUNDSARESIC,DIAMONDPOWDER,ALUMINA,TIC,BNANDWC1–9THELATESTDEVELOPMENTINELECTROLESSCODEPOSITIONISTHEINCORPORATIONOFPOLYTETRAFLUOROETHYLENEPTFEWITHNICKELPTFEPARTICLESAREADDEDTOTHESOLUTIONINTHEFORMOFAWATERDISPERSION10,11THEPROPERTIESOFELECTROLESSNI–PTFECOATINGSSUCHASWEARRESISTANCE,CORROSIONRESISTANCE,FRICTIONCOEFFICIENT,MICROHARDNESSANDALLOTHERPROPERTIESAREEXCELLENT12–18THEPRODUCTION,PROPERTIESANDAPPLICATIONSOFCOMPOSITEELECTROLESSNI/PTFECOATINGSAREGOOD19,20UNIFORMDISPERSIBILITYOFPTFEPARTICLESISOBTAINEDINELECTROLESSNICKELCOMPOSITEPLATING21,22DUNCAN13DEPOSITEDCOATINGSWHICHCONTAIN10–30VOL,03–04MMDIAMETERPARTICLESOFPTFEWITH5–10WTPTHECOEFFICIENTOFFRICTIONISTYPICALLY01–02FORNONLUBRICATEDCONDITIONSITWASALSOFOUNDFROMMICROHARDNESSTESTSANDWEARTESTSTHATTHEHARDNESSOFCOMPOSITECOATINGSWITH14–16PTFEWASTYPICALLY250–400HV,WHILETHEHARDNESSOFTHOSEWITH26PTFEHADONLY275HVAFTERHEATTREATMENTAT300UCHARDNESSVALUESWEREINCREASEDTO625–700HVAND400HV,RESPECTIVELYHADLEYANDHARLAND17DESCRIBEDACOATINGCONTAININGUPTO25WTPTFEUNIFORMLYDISTRIBUTEDINCHEMICALNI–PCONTAINING846NI–7P–84PTFEWTANDWITHASPECIFICGRAVITY65THEYALSOFOUNDTHATHARDNESSDEPENDSONHEATTREATMENTNISHIRAETAL23FOUNDTHATSUSPENSIONOFPTFEPARTICLESINANELECTROLESSNI–PBATHWASAFFECTEDBYNONIONICANDCATIONICSURFACTANTSMATSUDAETAL24FOUNDTHATPTFEPARTICLESWERECODEPOSITEDINELECTROLESSNI–PPLATEDFILMTHISCODEPOSITIONDEPENDSONSURFACTANTTYPE,IEZETAPOTENTIALOFPARTICLESURFACEINTHEPLATINGSOLUTIONANDCONTENTOFPARTICLESINFILMSPTFEHASBEENUSEDASAVERSATILEMATERIALTOPROTECTPARTSFROMCORROSIONANDWEAR25DANIELSANDHARME26FOUNDTHATTHENI–PTFECOATINGINCREASESSERVICELIFEANDPRODUCTQUALITYINPLASTICMANUFACTURE26ZHENGSHANETAL27REPORTEDTHEMORPHOLOGYANDSTRUCTUREOFNI–P–PTFECOATINGSTHISIMPARTSCONSIDERABLENONGALLING,DRYLUBRICANTPROPERTIESTOTHECENTRALELECTROCHEMICALRESEARCHINSTITUTE,KARAIKUDI–630006,TAMILNADU,INDIACORRESPONDINGAUTHOR,EMAILK_N_SRINIVASANYAHOOCOM?2005INSTITUTEOFMATERIALS,MINERALSANDMININGPUBLISHEDBYMANEYONBEHALFOFTHEINSTITUTERECEIVED13SEPTEMBER2004ACCEPTED8NOVEMBER2004156SURFACEENGINEERING2005VOL21NO2DOI101179/174329405X40902DETERMINATIONOFHARDNESSTHECLEANEDMILDSTEELPANELSWEREPLATEDWITHEN/PTFEANDTHEHARDNESSWASMEASUREDUSINGTHEVICKER’SHARDNESSMETHODTHEDIAGONALOFTHEDIAMONDSHAPEDINDENTATIONMADEBYAPPLYINGAKNOWNLOADTHROUGHADIAMONDINDENTORFORADEFINITETIMEWASMEASUREDUSINGAMICROSCOPEFITTEDWITHACALIBRATOREYEPIECETHEVICKER’SHARDNESSWASCALCULATEDFROMTHELENGTHOFTHEDIAGONALDETERMINATIONOFABRASIONRESISTANCEUSINGTABERABRASERTHEEN/PTFEPLATEDSPECIMENWASWEIGHED,THENPLACEDUNDERAPAIROFWEIGHTEDABRADINGWHEELSEACH500GOFCLOSELYCONTROLLEDCOMPOSITIONINSUCHAMANNERASTOCAUSESIDESLIPBETWEENTHEABRADINGWHEELSANDTHESURFACEOFTHETESTSPECIMENTHEWHEELSROTATEDONTHESPECIMENFOR1000REVOLUTIONS,AFTERWHICHTHEPANELWASWEIGHEDAGAINTHEDIFFERENCEINWEIGHTSWASTHEWEARINDEXTABERINDEXORRATEOFWEARTHEEXPERIMENTSWEREREPEATEDTWICE,ANDTHEAVERAGEVALUEWASTAKENTHESAMEEXPERIMENTWASCARRIEDOUTUSINGASPECIMENWHICHWASPLATEDWITHELECTROLESSNICKELONLY,ANDTHEABRASIONRESISTANCEPROPERTIESOFBOTHTHESPECIMENS,WITHANDWITHOUTPTFE,WERECOMPAREDEFFECTOFHEATTREATMENTONHARDNESSTWOSIMILARPANELSWERETAKENONEWASPLATEDWITHNICKELALONEANDTHEOTHERWITHNICKEL/PTFECOMPOSITEBOTHWEREHEATTREATEDAT400UCFOR1HANDTHENTESTEDFORABRASIONRESISTANCEUSINGTHETABERABRASERANALYSISOFNICKELANDPHOSPHOROUSINDEPOSITSTAINLESSSTEELPANELSWEREDEPOSITEDWITHEN/PTFEDEPOSITINVARIOUSCONDITIONSTHEPANELWASETCHEDINCONCENTRATEDHYDROCHLORICACIDFOR1–2MINANDACTIVATEDINPALLADIUMCHLORIDESOLUTIONTHENITWASPLATEDWITHEN/PTFECOMPOSITETHEDEPOSITWASREMOVEDFROMTHEPANEL,WEIGHED,DISSOLVEDIN20MLOF40NITRICACIDANDINCREASEDTO100MLINASTANDARDMEASURINGFLASKNICKELCONTENTINTHESOLUTIONWASANALYSEDVOLUMETRICALLYBYTHEEDTAMETHODANDPHOSPHOROUSBYTHEAMMONIUMPHOSPHOMOLYBDATEMETHODCORROSIONMEASUREMENTSBYPOTENTIOSTATICPOLARISATIONTWOMILDSTEELSAMPLESWERECUTTO75615MM,MECHANICALLYPOLISHED,DEGREASEDWITHTRICHLOROETHYLENEANDETCHEDIN20SULPHURICACIDAT60UCOR2MINONESPECIMENPLATEDWITHNICKELALONEANDTHEOTHERWITHEN/PTFECOMPOSITEFOR2HAT90UCANDPH55POLARISATIONMEASUREMENTSWERECARRIEDOUTPOTENTIOSTATICALLYBYEXPOSINGA1CM2AREAOFEACHPLATEDSPECIMENBOTHWITHANDWITHOUTPTFEUSINGAPOTENTIOSTATPLATINUMWASUSEDASANAUXILLIARYELECTRODEANDASATURATEDCALOMELELECTRODEASTHEREFERENCEELECTRODETHEELECTROLYTEUSEDINTHESTUDYWAS3SODIUMCHLORIDEBOTHANODICANDCATHODICPOLARISATIONSWERECARRIEDOUTAGRAPHWASDRAWNWITHCURRENTDENSITYAGAINSTPOTENTIALUSINGTHETAFELEXTRAPOLATIONMETHOD,THECORROSIONCURRENTANDCORROSIONPOTENTIALSWEREDETERMINEDTHECORROSIONRATEINMILLILITRESPERYEARWASCALCULATEDRESULTSANDDISCUSSIONSEFFECTOFTEMPERATURETHEEFFECTOFTEMPERATUREONTHERATEOFDEPOSITIONISSHOWNINTABLE1THERATEOFDEPOSITIONINCREASESWITHTEMPERATUREANINCREASEINSOLUTIONTEMPERATUREINCREASESTHEFLOWOFTHESOLUTIONTOWARDSTHEELECTRODEBYCONVECTIONBECAUSETHEELECTROLESSPLATINGOFMETALSINVARIABLYINVOLVESAREACTIONPROCEEDINGATARATELIMITEDBYDIFFUSION,INCREASINGTHETEMPERATUREOFTHESOLUTIONFAVOURSMORENICKELIONMOVEMENTTOWARDSTHEELECTRODES,WHICHLEADSTOAHIGHRATEOFDEPOSITIONTHEVOLUMEPERCENTAGEOFPTFECODEPOSITEDWASALSOFOUNDTOINCREASEWITHRISINGTEMPERATUREEFFECTOFDEPOSITIONTIMETABLE2SHOWSTHECHANGEINTHICKNESSOFTHEDEPOSITWITHINCREASEINDEPOSITIONTIMEITWASFOUNDTHAT,ASTHEDEPOSITIONTIMEINCREASES,THETHICKNESSOFTHEDEPOSITALSOINCREASESEFFECTOFCONCENTRATIONOFPTFEINBATHTHEPTFECONTENTINTHEBATHWASVARIEDFROM5GL–1TO20GL–1,ANDTHENICKELANDPHOSPHOROUSCONTENTINTHEDEPOSITSWASANALYSEDTHEANALYSISSHOWEDTHATTHEHYPOPHOSPHITEADDEDTOREDUCENI2ZPRODUCEDAPHOSPHOROUSCONTENTOF8THEAMOUNTOFNICKELINTHEDEPOSITWASFOUNDTODECREASEASTHEPTFECONCENTRATIONINCREASEDTHISCONFIRMSTHATTHEREISANINCREASEINTHEVOLUMEPERCENTAGEOFPTFEWITHANINCREASEINITSCONCENTRATIONTHEVOLUMEPERCENTAGEOFPTFEATTAINEDACONSTANTVALUEFROM15GL–1ONWARDSTHEEFFECTOFCONCENTRATIONOFPTFEISGIVENINTABLE3TABLE1INFLUENCEOFTEMPERATUREOFBATHONRATEOFDEPOSITIONATPH55TEMPERATURE,UCRATEOFDEPOSITION,MMH–160377050808090105TABLE3EFFECTOFCONCENTRATIONOFPTFEINBATHCONCENTRATIONOFPTFE,GL–1PTFEINEN/PTFEDEPOSIT,VOL5180720892261124013248152491725019250TABLE2EFFECTOFPLATINGTIMEONTHICKNESSOFDEPOSITATBATHTEMPERATURE90UCANDPH55THICKNESSOFDEPOSIT,MMTIMEOFDEPOSITION,H10511792259330845381SRINIVASANANDJOHNELECTROLESSNICKEL–PTFECOMPOSITECOATINGS158SURFACEENGINEERING2005VOL21NO2

簡(jiǎn)介：ACOMPLETEANDGENERALSOLUTIONTOTHEFORWARDKINEMATICSPROBLEMOFPLATFORMTYPEROBOTICMANIPULATORSXIAOLUNSHIDEPARTMENTOFSYSTEMSENGINEERINGTHECHINESEUNIVERSITYOFHONGKONGABSTRACTINTHISPAPERAGENERALMETHODISPRESENTED,BASEDONTHEDATAOFTHREEPOINTPOSITIONS,VELOCITIESANDACCELERATIONSOFTHEENDEFFECTOR,FORSOLVINGTHEFORWARDKINEMATICSPROBLEMOFANYPLATFORMTYPEMANIPULATOR,INCLUDINGTHE6DOFSTEWARTPLATFORMNUMERICALEXAMPLESAREINCLUDEDTODEMONSTRATETHEAPPLICATIONOFTHEMETHODITISSHOWNTHATTHEEQUATIONSFORTHEFORWARDPOSITIONKINEMATICSAREHIGHLYNONLINEAR,HOWEVER,CLOSEDFORMSOLUTIONSTOTHEFORWARDRATEKINEMATICSANDTHEFORWARDACCELERATIONKINEMATICSCANBEOBTAINEDBYSOLVINGASYSTEMOFLINEAREQUATIONSTHEADVANTAGESOFUSINGADDITIONALPASSIVEJOINTENCODERSISALSODISCUSSED,TOSIMPLIFYTHESOLUTIONOFTHEPOSITIONKINEMATICSPROBLEM,ANDOBTAINAONETOONERELATIONBETWEENTHEACTUATEDJOINTVARIABLESANDTHEENDEFFECTORCONFIGURATIONS1INTRODUCTIONTHEANTHROPOMORPHICOPENCHAINMECHANISMSOFSERIALTYPEINDUSTRIALROBOTARMSHAVEANUMBEROFADVANTAGESSUCHASLONGREACH,LARGEWORKSPACEANDDEXTROUSMANEUVERABILITYHOWEVER,THELOWRIGIDITYOFTHECANTILEVEREDSTRUCTUREOFTHEOPENCHAINMECHANISMISASERIOUSDISADVANTAGE,ANDITISNOTSUITABLEFORHIGHSPEEDORPRECISIONOPERATIONSANALTERNATIVETOTHESERIALTYPEMANIPULATIONDEVICEISTHEPARALLELMECHANISMSUCHASTHESTEWARTPLATFORMLTHEREDUCEDMASSOFTHEMOVINGPARTS,TOGETHERWITHTHESIGNIFICANTLYIMPROVEDENDPOINTSTIFFNESSOFTHETRUSSLIKESTRUCTUREOFTHEPARALLELMECHANISM,RESULTSINHIGHPOSITIONINGACCURACYANDGOODDYNAMICPERFORMANCEAGREATDEALOFRESEARCHWORKHASBEENDONEINTHEAREAOFTHEKINEMATICANALYSISOFPARALLELMANIPULATORSHUNT2,INHISBOOK,SUGGESTEDTHATTHEMANIPULATIONCAPABILITYOFTHEPARALLELMECHANISMBEUTILIZEDINROBOTSANDHELATER3LISTEDANUMBEROFPOSSIBLESTRUCTURESOFPARALLELMECHANISMSSUITABLEFORROBOTICAPPLICATIONSYANGETAL4,FROMTHEKINEMATICPOINTOFVIEW,STUDIEDTHEFEASIBILITYOFAPPLYINGSUCHAMECHANICALDEVICEINROBOTICSFITCHER5PERFORMEDADETAILEDTHEORETICALANDEXPERIMENTALINVESTIGATIONOFRGFENTONDEPARTMENTOFMECHANICALENGINEERINGTHEUNIVERSITYOFTORONTOASTEWARTPLATFORMTYPEMANIPULATORRECENTLY,MOHAMEDETAL6,SUGIMOTO7,SHIETAL8ANDBEHI9RESPECTIVELY,DEVELOPEDCOMPUTATIONALSCHEMESFORSOLVINGTHEINSTANTANEOUSKINEMATICSOFPARALLELMECHANISMS,SUCHASTHESTEWARTPLATFORM,USINGSCREWTHEORY,THECONCEPTOFPARTIALTWIST6ANDOTHERTECHNIQUESLEEETALLOANDWALDRONETALLL,RESPECTIVELY,DEVELOPEDSOLUTIONSTOTHEFORWARDPOSITIONKINEMATICSPROBLEMFORA3DOFINPARALLELACTUATEDMANIPULATOR,ANDAHYBRIDSERIALPARALLELMANIPULATORCONTAININGA3DOFPARALLELMODULENANUAETAL12PRESENTEDASOLUTIONFORTHEFORWARDPOSITIONKINEMATICSOFASPECIALFORMOFTHE6DOFSTEWARTPLATFORMHOWEVER,MOSTOFTHESEMETHODSEITHERINVOLVEALLPASSIVEJOINTVARIABLESANDTHUSTHESOLUTIONPROCEDURESAREVERYCOMPLICATED,ORCANONLYBEAPPLIEDTOCERTAINSIMPLIFIEDVERSIONSOFTHEPLATFORMTYPEMANIPULATORANEFFECTIVE,GENERALANDUNIFIEDSOLUTIONFORTHEFORWARDKINEMATICSPROBLEMOFPLATFORMTYPEMANIPULATORS,INCLUDINGPOSITION,VELOCITYANDACCELERATIONKINEMATICS,ISSTILLUNAVAILABLEATPRESENTINTHISPAPER,AGENERALMETHODISPRESENTEDFORSOLVINGTHEFORWARDKINEMATICSPROBLEMOFPLATFORMTYPEMANIPULATORS,USINGTHEPOSITIONS,VELOCITIES,ANDACCELERATIONSOFTHREEPOINTSOFTHEMOVINGPLATFORMENDEFFECTORTHISMETHODREQUIRESTHESOLUTIONOFONLYAFEWOFTHEPASSIVEJOINTVARIABLESANDTHUSTHEMETHODISCOMPUTATIONALLYEFFICIENT,ANDITSIMPLEMENTATIONISSTRAIGHTFORWARD2FORWARDPOSITIONKINEMATICSLETUSFIRSTCONSIDERA6DOFSTEWARTPLATFORMASSHOWNINFIGURE1THETHREENONCOLLINEARPOINTSOFTHEMOVINGPLATFORMUNDERCONSIDERATIONARE,RESPECTIVELY,PII1,3THECOORDINATESOFTHETHREEPOINTSEXPRESSEDWITHRESPECTTOTHEBASEREFERENCEFRAME0XY2CANBEREPRESENTEDBY10504729B4030001994IEEE3055FIGURE3THETOPVIEWOFASYMMETRIC6DOFPLATFORMSIMILARLY,THEUNITVECTORJREPRESENTINGTHEORIENTATIONOFTHE,YEAXISWITHRESPECTTOTHEBASEFRAMEISTHEUNITVECTORKREPRESENTINGTHEORIENTATIONOFTHEZEAXISWITHRESPECTTOTHEBASE,THEN,CANBEDETERMINEDUSINGTHECROSSPRODUCT24KIXJQSINSINA7IL,QSINPCOSAI7RIANDP,INGENERAL,CONTAINSIXUNKNOWNVARIABLES,AANDPI,WHICHMUSTBEELIMINATEDBEFORETHEPOSITIONANDORIENTATIONOFTHEENDEFFECTORCANACTUALLYBEDETERMINEDTOTHISEND,SIXCONSTRAINTEQUATIONSAREREQUIRED,OFWHICHTHREECANBEOBTAINEDUSINGTHETHREEPOINTVECTORS,PI,POINTSARETHECENTERSOFTHESPHERICDJOINTSCONNECTING43THEOTHERTHREEEXTENDIBLELINKSTOTHEMOVINGPLATFORMR32JTQI3ACOSP1Q2COSPZ2Q3COSP3ASSHOWNINFIGURE23051

簡(jiǎn)介：FIELDSTATICLOADTESTONKAOPINGHSICABLESTAYEDBRIDGEIKUANGFANG1CHUNRAYCHEN2ANDISHANGCHANG3ABSTRACTFIELDLOADTESTINGISANEFFECTIVEMETHODFORUNDERSTANDINGTHEBEHAVIORANDFUNDAMENTALCHARACTERISTICSOFACABLESTAYEDBRIDGETHISPAPERPRESENTSTHERESULTSOFFIELDSTATICLOADTESTSONTHEKAOPINGHSICABLESTAYEDBRIDGE,THELONGESTCABLESTAYEDBRIDGEINTAIWAN,BEFOREITWASOPENTOTRAFFICATOTALOF40LOADINGCASES,INCLUDINGTHEUNITANDDISTRIBUTEDBENDINGANDTORSIONLOADINGEFFECTS,WERECONDUCTEDTOINVESTIGATETHEBRIDGEBEHAVIORTHEATMOSPHERICTEMPERATUREEFFECTONTHEVARIATIONSOFTHEMAINGIRDERDEFLECTIONSWASALSOMONITOREDTHERESULTSOFSTATICLOADTESTINGINCLUDETHEMAINGIRDERDEFLECTIONS,THEFLEXURALSTRAINSOFTHEPRESTRESSEDCONCRETEGIRDER,ANDTHEVARIATIONSOFTHECABLEFORCESATHREEDIMENSIONALFINITEELEMENTMODELWASDEVELOPEDTHERESULTSSHOWTHATTHEBRIDGEUNDERTHEPLANNEDLOADTESTCONDITIONSHASLINEARSUPERPOSITIONCHARACTERISTICSANDTHEANALYTICALMODELSHOWSAVERYGOODAGREEMENTWITHTHEBRIDGERESPONSESFURTHERDISCUSSIONOFDEFLECTIONANDCABLEFORCESOFTHEDESIGNSPECIFICATIONSFORACABLESTAYEDBRIDGEISALSOPRESENTEDDOI101061/ASCE10840702200496531CEDATABASESUBJECTHEADINGSBRIDGES,CABLESTAYEDFINITEELEMENTMETHODSTATICLOADSLOADTESTSMONITORINGTAIWANINTRODUCTIONMODERNCABLESTAYEDBRIDGES,AESTHETICALLYAPPEALINGANDTECHNICALLYINNOVATIVE,HAVEBECOMEINCREASINGLYPOPULARWORLDWIDEINTHEPASTDECADESTROITSKY1977GIMSING1999BECAUSEOFIMPROVEMENTSINANALYSISTOOLSANDCONSTRUCTIONTECHNOLOGY,THESPANLENGTHOFCABLESTAYEDBRIDGESHASBECOMEMUCHLONGERWITHINCREASINGSPANLENGTH,THEBEHAVIOROFCABLESTAYEDBRIDGESBECOMESMORECOMPLEX,ANDTHEFUNDAMENTALCHARACTERISTICSSUCHASSTIFFNESS,VARIATIONSOFCABLEFORCES,ANDSTABILITYOFCABLESTAYEDBRIDGESBECOMEMOREIMPORTANTFOREVALUATINGTHESAFETYOFTHESEBRIDGESINGENERAL,FIELDLOADTESTINGISANEFFECTIVEMETHODTOINVESTIGATETHEFUNDAMENTALBEHAVIORANDTOESTABLISHTHEESSENTIALDATAOFACABLESTAYEDBRIDGEINADDITION,FORLONGSPANCABLESTAYEDBRIDGES,ESTABLISHINGAFINITEELEMENTMODELCORRELATEDREASONABLYWITHTHERESULTSOFFIELDLOADTESTSISIMPORTANTFORFUTUREMAINTENANCEWORKDURINGTHEPASTDECADE,SOMERESULTSOFFIELDLOADTESTSANDANALYTICALMODELSHAVEBEENREPORTEDFORLARGECABLESTAYEDBRIDGESHULSEYANDDELANEY1993PRESENTEDSTATICLOADTESTRESULTSANDCOMPARISONSWITHATWODIMENSIONALFINITEELEMENTMODELFORTHECAPTAINWILLIAMMOORECREEKCABLESTAYEDBRIDGECHANGETAL2001ANDZHANGETAL2001PRESENTEDTHEAMBIENTVIBRATIONTESTANDTHREEDIMENSIONAL3DFINITEELEMENTMODELFORTHEKAPSHUIMUNCABLESTAYEDBRIDGEINHONGKONGCUNHAETAL2001DESCRIBEDAMBIENTANDFREEVIBRATIONTESTRESULTS,SHOWINGGOODCORRELATIONWITHTHE3DFINITEELEMENTMODEL,FORTHEVASCODAGAMABRIDGEWORSAKETAL1992SUMMARIZEDTHEMODELINGOFTHECOMPONENTSOFAFINITEELEMENTMODEL,IE,THEPYLON,DECK,JOINTS,ANDCABLES,FORCABLESTAYEDBRIDGESCHANGESINTHESTAYEDCABLEFORCESCANRESULTINSIGNIFICANTVARIATIONSOFTHEINTERNALFORCESINBOTHTHEPYLONANDTHEDECKCASAS1994SHOWEDTHATA10CHANGEINCABLEFORCESWOULDCAUSEALMOST100VARIATIONSOFMOMENTINTHEPYLONANDABOUT300VARIATIONSOFMOMENTINTHEDECKBOTHDURINGTHECONSTRUCTIONSTAGEOFACABLESTAYEDBRIDGEANDAFTERITISOPENEDTOTRAFFIC,ITISIMPORTANTTOACCURATELYASSESSTHEFORCESCARRIEDBYTHESTAYEDCABLESTODATE,THEREAREMANYMETHODSTOEVALUATETHECABLEFORCESFORCABLESTAYEDBRIDGES,SUCHASMEASUREMENTOFTHEFORCEINTHETENSIONINGJACK,APPLICATIONOFALOADCELLATTHEANCHORAGEDEVICE,MEASUREMENTOFELONGATIONOFTHECABLESDURINGTENSIONINGANDINSTALLATIONOFSTRAINGAUGESINTHESTRANDS,ETCSOMERESEARCHERSHAVEPRESENTEDDIFFERENTMETHODOLOGIESINMEASURINGTHEFORCESOFTHESTAYEDCABLESBASEDONTHEVIBRATIONMETHODSHINKEETAL1980CASAS1994SHIMADA1994ZUIETAL1996OFTHESE,THEAMBIENTVIBRATIONMETHODBASEDONTHEVIBRATINGCHORDTHEORYISARELATIVELYSIMPLEANDAPPROPRIATETECHNIQUETOASSESSTHEFORCESINTHESTAYEDCABLESCASAS1994THEEFFECTIVELENGTHANDNATURALFREQUENCIESOFTHESTAYEDCABLESARETHEMOSTIMPORTANTFACTORSRELATEDTOTHEACCURACYOFTHEPREDICTIONOFCABLEFORCESTHISPAPERPRESENTSTHECONFIGURATIONANDRESULTSOFFIELDSTATICLOADTESTSONTHEKAOPINGHSICABLESTAYEDBRIDGEINTAIWANTHERESPONSESOFTHELOADTESTINCLUDEDEFLECTIONSOFTHEDECK,LONGITUDINALSTRAINSOFTHEPRESTRESSEDCONCRETEPCGIRDER,ANDVARIATIONOFTHECABLEFORCESTHEEFFECTIVELENGTHANDNATURALFREQUENCIESOFTHESTAYEDCABLESAREINVESTIGATEDTHEMEASUREDDEFLECTIONANDCABLEFORCESRELATEDTOTHEDESIGNSPECIFICATIONSOFTHECABLESTAYEDBRIDGEAREALSODISCUSSEDATHREEDIMENSIONALFINITEELEMENTMODELWASESTABLISHEDUSINGTHESAP2000PLUSPROGRAMANDCORRELATEDWITHTHERESULTSOFSTATICLOADTESTSFORFUTURERESEARCH1PROFESSOR,DEPTOFCIVILENGINEERING,NATIONALCHENGKUNGUNIV,TAINAN701,TAIWAN,ROCEMAILFANGLOUMAILNCKUEDUTW2DOCTORALCANDIDATE,DEPTOFCIVILENGINEERING,NATIONALCHENGKUNGUNIV,TAINAN701,TAIWAN,ROC3FORMERLY,GRADUATESTUDENT,DEPTOFCIVILENGINEERING,NATIONALCHENGKUNGUNIV,TAINAN701,TAIWAN,ROCNOTEDISCUSSIONOPENUNTILAPRIL1,2005SEPARATEDISCUSSIONSMUSTBESUBMITTEDFORINDIVIDUALPAPERSTOEXTENDTHECLOSINGDATEBYONEMONTH,AWRITTENREQUESTMUSTBEFILEDWITHTHEASCEMANAGINGEDITORTHEMANUSCRIPTFORTHISPAPERWASSUBMITTEDFORREVIEWANDPOSSIBLEPUBLICATIONONMARCH7,2003APPROVEDONAUGUST26,2003THISPAPERISPARTOFTHEJOURNALOFBRIDGEENGINEERING,VOL9,NO6,NOVEMBER1,2004?ASCE,ISSN10840702/2004/6531–540/1800JOURNALOFBRIDGEENGINEERING?ASCE/NOVEMBER/DECEMBER2004/531JBRIDGEENG20049531540DOWNLOADEDFROMASCELIBRARYORGBYUNIVERSITY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