簡介：2950英文單詞，英文單詞，16萬英文字符，中文萬英文字符，中文4900字文獻(xiàn)出處文獻(xiàn)出處ERRATTAHIR,HANNANIAE,OUAHMANEHAUTOMATICSPEECHRECOGNITIONERRORSDETECTIONANDCORRECTIONAREVIEWJPROCEDIACOMPUTERSCIENCE,2018,1283237AUTOMATICSPEECHRECOGNITIONERRORSDETECTIONANDCORRECTIONAREVIEWRAHHALERRATTAHI,ASMAAELHANNANI,HASSANOUAHMANEABSTRACTEVENTHOUGHAUTOMATICSPEECHRECOGNITIONASRHASMATUREDTOTHEPOINTOFCOMMERCIALAPPLICATIONS,HIGHERRORRATEINSOMESPEECHRECOGNITIONDOMAINSREMAINASONEOFTHEMAINIMPEDIMENTFACTORSTOTHEWIDEADOPTIONOFSPEECHTECHNOLOGY,ANDESPECIALLYFORCONTINUOUSLARGEVOCABULARYSPEECHRECOGNITIONAPPLICATIONSTHEPERSISTENTPRESENCEOFASRERRORSHAVEINTENSIFIEDTHENEEDTOFINDALTERNATIVETECHNIQUESTOAUTOMATICALLYDETECTANDCORRECTSUCHERRORSTHECORRECTIONOFTHETRANSCRIPTIONERRORSISVERYCRUCIALNOTONLYTOIMPROVETHESPEECHRECOGNITIONACCURACY,BUTALSOTOAVOIDTHEPROPAGATIONOFTHEERRORSTOTHESUBSEQUENTLANGUAGEPROCESSINGMODULESSUCHASMACHINETRANSLATIONINTHISPAPER,BASICPRINCIPLESOFASREVALUATIONAREFIRSTSUMMARIZED,ANDTHENTHESTATEOFTHECURRENTASRERRORSDETECTIONANDCORRECTIONRESEARCHISREVIEWEDWEFOCUSONEMERGINGTECHNIQUESUSINGWORDERRORRATEMETRICKEYWORDSAUTOMATICSPEECHRECOGNITIONASRERRORDETECTIONASRERRORCORRECTIONASREVALUATION1INTRODUCTIONAUTOMATICSPEECHRECOGNITIONASRSYSTEMSAIMSATCONVERTINGASPEECHSIGNALINTOASEQUENCEOFWORDSEITHERFORTEXTBASEDCOMMUNICATIONPURPOSESORFORDEVICECONTROLLINGTHEPURPOSEOFEVALUATINGASRSYSTEMSISTOSIMULATEHUMANJUDGEMENTOFTHEPERFORMANCEOFTHESYSTEMSINORDERTOMEASURETHEIRUSEFULNESSANDASSESSTHEREMAININGDIFFICULTIESANDESPECIALLYWHENCOMPARINGSYSTEMSTHESTANDARDMETRICOFASREVALUATIONISTHEWORDERRORRATE,WHICHISDEFINEDASTHEPROPORTIONOFWORDERRORSTOWORDSPROCESSEDASRHASMATUREDTOTHEPOINTOFCOMMERCIALAPPLICATIONSBYPROVIDINGTRANSCRIPTIONWITHANACCEPTABLELEVELOFPERFORMANCEWHICHALLOWSINTEGRATIONINTOMANYAPPLICATIONSINGENERAL,ASRSYSTEMSAREEFFECTIVEWHENTHECONDITIONSAREWELLCONTROLLEDNEVERTHELESS,THEYARETOODEPENDENTONTHETASKBEINGPERFORMEDANDTHERESULTSAREFARFROMIDEAL,ANDESPECIALLYFORLARGEVOCABULARYCONTINUOUSSPEECHRECOGNITIONLVCSRAPPLICATIONSTHISLATERSTILLONEOFTHEMOSTCHALLENGINGTASKSINTHEFIELD,DUETOANUMBEROFFACTORS,INCLUDINGPOORARTICULATION,VARIABLESPEAKINGRATEANDHIGHDEGREEOFACOUSTICVARIABILITYCAUSEDBYNOISE,SIDESPEECH,ACCENTS,SLOPPYPRONUNCIATION,HESITATION,REPETITION,INTERRUPTIONSANDCHANNELMISMATCH,AND/ORDISTORTIONSTODEALWITHALLTHESEPROBLEMS,THEREHASBEENAPLETHORAOFALGORITHMSANDTECHNOLOGIESPROPOSEDBYTHESCIENTIFICCOMMUNITIESFORALLSTEPSOFLVCSROVERTHELASTDECADEPREPROCESSING,FEATUREEXTRACTION,ACOUSTICMODELING,LANGUAGEMODELING,DECODINGANDRESULTPOSTPROCESSINGNEVERTHELESSLVCSRSYSTEMSARENOTYETROBUSTWITHERRORRATESOFUPTO50UNDERCERTAINCONDITIONS21,8THEPERSISTENTPRESENCEOFASRERRORSMOTIVATESTHEATTEMPTTOFINDALTERNATIVETECHNIQUESTOASSISTUSERSINCORRECTINGTHETRANSCRIPTIONERRORSORTOTOTALLYAUTOMATETHECORRECTIONPROCESSEVALUATIONPROCEDUREINOTHERWORDS,THEREFERENCEANDRECOGNISEDWORDSGETMATCHEDINORDERTODECIDEWHICHWORDHAVEBEENDELETEDORINSERTED,ANDWHICHREFERENCERECOGNISEDSTRINGPAIRSHAVEBEENALIGNEDTOEACHOTHER,WHICHMAYRESULTINAHITORASUBSTITUTIONTHISISNORMALLYDONEBYUSINGTHEVITERBIEDITDISTANCE17TOEFFICIENTLYSELECTTHEREFERENCEANDTHERECOGNISEDWORDSEQUENCEALIGNMENTFORWHICHTHEWEIGHTEDERRORSCOREISMINIMIZEDTHEEDITDISTANCEUSUALLYALIGNSANIDENTICALWEIGHTS1FORTHELEVENSTHEINDISTANCETOALLTHREE,INSERTION,SUBSTITUTIONANDDELETIONYET,UNIFIEDWEIGHTSMAYPRESENTADOUBTTOCHOOSETHEBESTPATHALIGNMENTINTHECASEWHENWEHAVEDIFFERENTONESWHICHHAVETHESAMESCORETOAVOIDTHISPROBLEMMORRISETAL12SUGGESTUSINGDIFFERENTWEIGHTS,SUCHTHATSUBSTITUTIONWILLBEFAVOUREDTHANINSERTIONANDDELETIONINGENERAL,IT’SRECOMMENDEDTOPUTWIWD,ANDWSWIWSWHEREWI,WSANDWDARERESPECTIVELYTHEWEIGHTOFINSERTION,SUBSTITUTION,ANDDELETION23ASREVALUATIONMETRICSACCORDINGTOMCCOWANETAL11ANIDEALASREVALUATIONMETRICSHOULDBEIDIRECTMEASUREASRCOMPONENTINDEPENDENTLYONTHEASRAPPLICATION,IIOBJECTIVETHEMEASURESHOULDBECALCULATEDINANAUTOMATEDMANNER,IIIINTERPRETABLETHEABSOLUTEVALUEOFTHEMEASUREMUSTGIVEANIDEAABOUTTHEPERFORMANCE,ANDIVMODULARTHEEVALUATIONMEASURESHOULDBEGENERALTOALLOWTHOROUGHAPPLICATIONDEPENDENTANALYSISWORDERRORRATEWERISTHEMOSTPOPULARMETRICFORASREVALUATION,ITMEASURESTHEPERCENTAGEOFINCORRECTWORDSSUBSTITUTIONSS,INSERTIONSI,DELETIONSDREGARDINGTHETOTALNUMBEROFWORDSPROCESSEDITISDEFINEDASWER11WHEREITOTALNUMBEROFINSERTIONS,DTOTALNUMBEROFDELETIONS,STOTALNUMBEROFSUBSTITUTIONS,HTOTALNUMBEROFHITS,ANDN1TOTALNUMBEROFINPUTWORDSDESPITEOFBEINGTHEMOSTCOMMONLYUSED,WERHASMANYSHORTCOMINGS10FIRSTOFALL,WERISNOTATRUEPERCENTAGEBECAUSEITHASNOUPPERBOUND,SOITDOESN’TTELLYOUHOWGOODASYSTEMIS,BUTONLYTHATONEISBETTERTHANANOTHERMOREOVER,WERISNOTD/ISYMMETRIC,SOINNOISYCONDITIONSWERCOULDEXCEED100,FORTHEFACTTHATITGIVESFARMOREWEIGHTTOINSERTIONSTHANTODELETIONSTHEWERSTILLEFFECTIVEFORSPEECHRECOGNITIONWHEREERRORSCANBECORRECTEDBYTYPING,SUCHAS,DICTATIONHOWEVER,FORALMOSTANYOTHERTYPEOFSPEECHRECOGNITIONSYSTEMS,WHERETHEGOALISMORETHANTRANSCRIPTION,ITISNECESSARYTOLOOKFORANALTERNATIVE,ORADDITIONAL,EVALUATIONFRAMEWORKMANYRESEARCHERSHAVEPROPOSEDALTERNATIVEMEASURESTOSOLVETHEEVIDENTLIMITATIONSOFWERIN12ANDREWETALINTRODUCEDTWOINFORMATIONTHEORETICMEASURESOFWORDINFORMATIONCO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簡介：THESOLUBILITIESOFBENZENEPOLYCARBOXYLICACIDSINWATERALEXANDERAPELBLATA,,EMANUELMANZUROLAA,NAZMIAABOBALALBADEPARTMENTOFCHEMICALENGINEERING,BENGURIONUNIVERSITYOFTHENEGEV,POBOX653,BEERSHEVA84105,ISRAELBNEGEVACADEMICCOLLEGEOFENGINEERING,BEERSHEVA,ISRAELRECEIVED30MAY2005RECEIVEDINREVISEDFORM14JULY2005ACCEPTED14JULY2005AVAILABLEONLINE26AUGUST2005ABSTRACTTHESOLUBILITIESINWATEROFALLBENZENEPOLYCARBOXYLICACIDSAREDISCUSSED,USINGDATADETERMINEDINTHISWORKBENZOIC,TEREPHTHALIC,TRIMELLITIC,TRIMESIC,ANDPYROMELLITICACIDSANDAVAILABLEFROMTHELITERATUREBENZOIC,PHTHALIC,ISOPHTHALIC,TEREPHTHALIC,HEMIMELLITIC,TRIMELITIC,TRIMESIC,MELLOPHANIC,PREHNITIC,PYROMELLITIC,BENZENEPENTACARBOXYLICANDMELLITICACIDSTHEAPPARENTMOLARENTHALPIESOFSOLUTIONATTHESATURATIONPOINTFORTHESEBENZENEPOLYCARBOXYLICACIDSWEREDETERMINEDFROMTHETEMPERATUREDEPENDENCEOFTHESOLUBILITIES?2005ELSEVIERLTDALLRIGHTSRESERVEDKEYWORDSBENZENEPOLYCARBOXYLICACIDSSATURATEDAQUEOUSSOLUTIONSMOLARENTHALPIESOFSOLUTION1INTRODUCTIONTHEREARE12BENZENECARBOXYLICACIDSONEMONOBASICACIDBENZOICACID,THREEDIBASICACIDS{BENZENE1,2DICARBOXYLICPHTHALICACID,BENZENE1,3DICARBOXYLICISOPHTHALICACID,ANDBENZENE1,4DICARBOXYLICTEREPHTHALICACID},THREETRIBASICACIDS{BENZENE1,2,3TRICARBOXYLICHEMIMELLITIC,BENZENE1,2,4TRICARBOXYLICTRIMELLITICACID,ANDBENZENE1,3,5TRICARBOXYLICTRIMESICACID},THREETETRABASICACIDS{BENZENE1,2,3,4TETRACARBOXYLICMELLOPHANICACID,BENZENE1,2,3,5TETRACARBOXYLICPREHNITICACIDANDBENZENE1,2,4,5TETRACARBOXYLICPYROMELLITICACID},ONEPENTABASICACIDBENZENEPENTACARBOXYLICACID,ANDONEHEXABASICACIDBENZENEHEXACARBOXYLICMELLITICACIDLOWERBENZENEPOLYCARBOXYLICACIDSESPECIALLYBENZOICANDPHTHALICACIDSAREPRODUCEDINLARGEQUANTITIESALONGWITHTHEIRVARIOUSESTERDERIVATIVESAREUSEDASINTERMEDIATESINTHEPREPARATIONSOFRESINS,PLASTICIZERS,DYES,INKS,ADHESIVES,ALKALOIDALSOLUTIONS,PHARMACEUTICALANTIFUNGALAIDSANDINTHEPRESERVATIONOFFOODS,FATS,ANDFRUITJUICES1–5ULTRAPUREBENZOICACIDSERVESASASTANDARDINTITRIMETRICANDCALORIMETRICEXPERIMENTSTHEHIGHERBENZENEPOLYCARBOXYLICACIDSARELESSIMPORTANTCOMMERCIALLYHOWEVER,ASTHEYAREFORMEDBYTHEDRASTICOXIDATIONOFGRAPHITE,COALS,WOODLIGNINANDSIMILARMATERIALS,THEYHAVEGEOCHEMICALANDECOLOGICALSIGNIFICANCETHEYAREALSOOFINTERESTINTHEENVIRONMENTALCHEMISTRYOFNATURALWATERSDUETOTHEFORMATIONOFTOXICMETALBENZENEPOLYCARBOXYLICLIGANDS6THESOLUBILITYOFBENZENEPOLYCARBOXYLICACIDSINWATERASAFUNCTIONOFTEMPERATUREVARIESSIGNIFICANTLYUSUALLY,THESOLUBILITYISSMALLANDEVENEXTREMELYSMALLFORTEREPHTHALICACIDTHEACCURACYANDTHEAGREEMENTBETWEENDIFFERENTSOLUBILITYEXPERIMENTSISNOTVERYGOOD7–9ITISCLEARFROMTHERECENTTABULATIONOFSOLUBILITIESOFORGANICCOMPOUNDSINWATERPREPAREDBYYALKOVSKYANDHE9THATONLYTHESOLUBILITIESOFBENZOICANDPHTHALICACIDSAREWELLDOCUMENTEDLESSATTENTIONWASPAIDTOOTHERBENZENEPOLYCARBOXYLICACIDSWHERETHESOLUBILITIESWEREDETERMINEDONLYONCEATONEORFEWTEMPERATURESINTHECONTEXTOFSEPARATION00219614/SEEFRONTMATTER?2005ELSEVIERLTDALLRIGHTSRESERVEDDOI101016/JJCT200507007CORRESPONDINGAUTHORTEL97286461487FAX97286472916EMAILADDRESSAPELBLATBGUACILAAPELBLATWWWELSEVIERCOM/LOCATE/JCTJCHEMTHERMODYNAMICS382006565–571OLNDMM?TOD1TT??DSOLHDTTR?1?0001HM1M?FF?1TOLNC2OLNDMM?T??TD1TWHEREHDENOTESANUMBEROFWATERMOLECULESINTHEHYDRATE,DSOLHTISTHEMOLARENTHALPYOFSOLUTION,C2ISTHEACTIVITYCOEFFICIENTOFTHESOLUTE,M1ISTHEMOLARMASSOFWATER,RISTHEGASCONSTANTANDM?1MOL?KG?1INEQUATION1,ITISASSUMEDTHATTHEDISSOCIATIONOFTHEBENZENEPOLYCARBOXYLICACIDSATTHESATURATIONPOINTISSMALL6ANDTHEYCANBETREATEDASNONELECTROLYTESORHYDRATEDNONELECTROLYTESASTHECHANGEOFACTIVITYCOEFFICIENTSWITHMNEARTHESATURATIONPOINTISUNKNOWN,THEFACTORFISREPLACEDBYUNITYANDTHEENTHALPYOFSOLUTIONBECOMESTHEAPPARENTMOLARENTHALPYOFSOLUTIONIFITISASSUMEDTHATTHEENTHALPYOFSOLUTIONDEPENDSLINEARLYONTHETEMPERATURE,THEINTEGRALFORMOFEQUATION1ISLNDMM?T?ATBDTKTTCLNDTKTD2TWHEREA,B,ANDCAREADJUSTABLECOEFFICIENTSWHICHWEREDETERMINEDBYANUNWEIGHTEDMULTIVARIABLELEASTSQUAREMETHODANDR2ISTHESQUAREDCORRECTIONCOEFFICIENTOFTHEREGRESSIONTHESECOEFFICIENTSAREREPORTEDINTABLE2FORBENZENEPOLYCARBOXYLICACIDSTHEYWERECALCULATEDCOMBININGTHESOLUBILITIESFROMTHISWORKANDFROMTHELITERATUREANDCANBETREATEDASTHE‘‘BEST’’SOLUBILITYCURVESITFOLLOWSFROMEQUATIONS1AND2THATTHEAPPARENTMOLARENTHALPYOFSOLUTIONATTHESATURATIONPOINTISDSOLHDTT?RD1?0001HM1MTDCT?BTD3TWHEREHVALUESWERETAKENFROMTHEYUKHNOANDBIKKULOVWORK11INORDERTOILLUSTRATETHEAGREEMENTBETWEENTHESOLUBILITIESCOMINGFROMDIFFERENTINVESTIGATIONSTHEYAREPLOTTEDINFIGURES1TO8BENZOICACIDWASSTUDIEDMANYTIMESINTHELITERATURE8ANDTHEREFOREONLYRESULTSOFSYSTEMATICDETERMINATIONSINTHE27315TO37315KARECONSIDEREDHERE2,7,10,11,15THESOLUBILITYOFBENZOICACIDISRELATIVELYHIGH,COMPAREDWITHOTHERBENZENEPOLYCARBOXYLICACIDS,ANDTHEREFOREAREASONABLEAGREEMENTBETWEENVARIOUSINVESTIGATIONSSHOULDBEEXPECTEDTHISEXPECTATIONISCONFIRMEDASCANBESEENINFIGURE1SIMILARTOBENZOICACID,THESOLUBILITYOFPHTHALICACIDINWATERISWELLKNOWN9–12,16–19,24ANDCONCORDANTFIGURE2PHTHALICACIDDISSOLVESMOREINWATERTHANBENZOICACIDANDCONSIDERABLYMORETHANOTHERISOMERICACIDS,ISOPHTHALICANDTEREPHTHALICACIDSINTHECASEOFISOPHTHALICACIDFIGURE3ITISCLEARTHATTHERESULTSOFFREIDLINANDDAVIDOV20DIFFERCONSIDERABLYFROMTHEMEASUREME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簡介：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,

簡介：7000英文單詞，英文單詞，4萬英文字符，中文萬英文字符，中文12500字文獻(xiàn)出處文獻(xiàn)出處HANSENSC,OTLEYDT,VANDERSTEDEWAPRACTICEDEVELOPMENTSINBUDGETINGANOVERVIEWANDRESEARCHPERSPECTIVEJJOURNALOFMANAGEMENTACCOUNTINGRESEARCH,2003,15195116PRACTICEDEVELOPMENTSINBUDGETINGANOVERVIEWANDRESEARCHPERSPECTIVESTEPHENCHANSEN,DAVIDTOTLEY,WIMAVANDERSTEDEABSTRACTPRACTITIONERSINEUROPEANDTHEUSRECENTLYHAVEPROPOSEDTWODISTINCTAPPROACHESTOADDRESSWHATTHEYBELIEVEARESHORTCOMINGSOFTRADITIONALBUDGETINGPRACTICESONEAPPROACHADVOCATESIMPROVINGTHEBUDGETINGPROCESSANDPRIMARILYFOCUSESONTHEPLANNINGPROBLEMSWITHBUDGETINGTHEOTHERADVOCATESABANDONINGTHEBUDGETANDPRIMARILYFOCUSESONTHEPERFORMANCEEVALUATIONPROBLEMSWITHBUDGETINGTHISPAPERPROVIDESANOVERVIEWANDRESEARCHPERSPECTIVEONTHESETWORECENTDEVELOPMENTSWEDISCUSSWHYPRACTITIONERSHAVEBECOMEDISSATISFIEDWITHBUDGETS,DESCRIBETHETWODISTINCTAPPROACHES,PLACETHEMINARESEARCHCONTEXT,SUGGESTINSIGHTSTHATMAYAIDTHEPRACTITIONERS,ANDUSETHEPRACTITIONERPERSPECTIVESTOIDENTIFYFRUITFULAREASFORRESEARCHINTRODUCTIONBUDGETINGISTHECORNERSTONEOFTHEMANAGEMENTCONTROLPROCESSINNEARLYALLORGANIZATIONS,BUTDESPITEITSWIDESPREADUSE,ITISFARFROMPERFECT1PRACTITIONERSEXPRESSCONCERNSABOUTUSINGBUDGETSFORPLANNINGANDPERFORMANCEEVALUATIONTHEPRACTITIONERSARGUETHATBUDGETSIMPEDETHEALLOCATIONOFORGANIZATIONALRESOURCESTOTHEIRBESTUSESANDENCOURAGEMYOPICDECISIONMAKINGANDOTHERDYSFUNCTIONALBUDGETGAMESTHEYATTRIBUTETHESEPROBLEMS,INPART,TOTRADITIONALBUDGETING’SFINANCIAL,TOPDOWN,COMMANDANDCONTROLORIENTATIONASEMBEDDEDINANNUALBUDGETPLANNINGANDPERFORMANCEEVALUATIONPROCESSESEG,SCHMIDT1992BUNCEETAL1995HOPEANDFRASER1997,2000,2003WALLANDER1999EKHOLMANDWALLIN2000MARCINO2000JENSEN2001WEDEMONSTRATEPRACTITIONERS’CONCERNSWITHBUDGETSBYDESCRIBINGTWOPRACTICELEDDEVELOPMENTSONEADVOCATINGIMPROVINGTHEBUDGETINGPROCESS,THEOTHERABANDONINGITTHESEDEVELOPMENTSILLUSTRATETWOPOINTSFIRST,THEYSHOWPRACTITIONERS’CONCERNSWITHBUDGETINGPROBLEMSTHATTHESCHOLARLYLITERATUREHASLARGELYIGNOREDWHILEFOCUSINGINSTEADONMORETRADITIONALISSUESLIKEPARTICIPATIVEBUDGETING2SECOND,THETWOCONFLICTINGDEVELOPMENTSILLUSTRATETHATFIRMSFACEACRITICALDECISIONREGARDINGBUDGETINGMAINTAINIT,IMPROVEIT,ORABANDONITOURDISCUSSIONHASTWOOBJECTIVESFIRST,WEDEMONSTRATETHELEVELOFCONCERNWITHBUDGETINGINPRACTICE,SUGGESTINGITSPOTENTIALFORCONTINUEDSCHOLARLYRESEARCHSECOND,WEWISHTORAISEACADEMICS’AWARENESSOFAPPARENTDISCONNECTSBETWEENBUDGETINGPRACTICEANDRESEARCHWEIDENTIFYAREASWHEREPRIORRESEARCHMAYAIDTHEPRACTITIONERSAND,CONVERSELY,USETHEPRACTITIONERS’INSIGHTSTOSUGGESTAREASFORRESEARCHINTHESECONDSECTION,WEREVIEWSOMEOFTHEMOSTCOMMONCRITICISMSOFBUDGETSINPRACTICETHETHIRDSECTIONDESCRIBESANDANALYZESTHEMAINTHRUSTOFTWORECENTPRACTICELEDDEVELOPMENTSINBUDGETINGINTHEFOURTHSECTION,WEPLACETHESETWOPRACTICEDEVELOPMENTSINARESEARCHCONTEXTANDSUGGESTRESEARCHTHATMAYBERELEVANTTOTHEPRACTITIONERSTHEFIFTHSECTIONTURNSTHETABLESBYCAUSESAMISMATCHWITHOPERATIONALANDSTRATEGICDECISIONSTHATEMPHASIZENONFINANCIALGOALSANDCUTACROSSTHEANNUALPLANNINGCYCLE,LEADINGTOBUDGETGAMESINVOLVINGSKILLFULTIMINGOFREVENUES,EXPENDITURES,ANDINVESTMENTSMERCHANT1985AFINALLY,CLAIMS7,11,AND12REFLECTORGANIZATIONALANDPEOPLERELATEDBUDGETINGISSUESTHECRITICSARGUETHATVERTICAL,COMMANDANDCONTROL,RESPONSIBILITYCENTERFOCUSEDBUDGETARYCONTROLSAREINCOMPATIBLEWITHFLAT,NETWORK,ORVALUECHAINBASEDORGANIZATIONALDESIGNSANDIMPEDEEMPOWEREDEMPLOYEESFROMMAKINGTHEBESTDECISIONSHOPEANDFRASER2003GIVENSUCHALONGLISTOFPROBLEMSANDMANYCALLSFORIMPROVEMENT,ITSEEMSODDTHATTHEVASTMAJORITYOFUSFIRMSRETAINAFORMALBUDGETINGPROCESS97PERCENTOFTHERESPONDENTSINUMAPATHY1987ONEREASONTHATBUDGETSMAYBERETAINEDINMOSTFIRMSISBECAUSETHEYARESODEEPLYINGRAINEDINANORGANIZATION’SFABRICSCAPENSANDROBERTS1993‘‘THEYREMAINACENTRALLYCOORDINATEDACTIVITYOFTENTHEONLYONEWITHINTHEBUSINESS’’NEELYETAL2001,9ANDCONSTITUTE‘‘THEONLYPROCESSTHATCOVERSALLAREASOFORGANIZATIONALACTIVITY’’OTLEY1999HOWEVER,AMORERECENTSURVEYOFFINNISHFIRMSFOUNDTHATALTHOUGH25PERCENTARERETAININGTHEIRTRADITIONALBUDGETINGSYSTEM,61PERCENTAREACTIVELYUPGRADINGTHEIRSYSTEM,AND14PERCENTAREEITHERABANDONINGBUDGETSORATLEASTCONSIDERINGITEKHOLMANDWALLIN2000WEDISCUSSTWOPRACTICELEDDEVELOPMENTSTHATILLUSTRATEPROPOSALSTOIMPROVEBUDGETINGORTOABANDONITALTHOUGHTHETWODEVELOPMENTSREACHDIFFERENTCONCLUSIONS,BOTHORIGINATEDINTHESAMEORGANIZATION,THECONSORTIUMFORADVANCEDMANUFACTURINGINTERNATIONALCAMIONEINTHEUSANDTHEOTHERINEUROPETHEUSBASEDCAMIACTIVITYBASEDBUDGETINGABBGROUPADVOCATESIMPROVINGTHEBUDGETINGSYSTEMBYMARRYINGAMORECOMPLETE,ACTIVITYBASEDOPERATIONALMODELWITHADETAILEDFINANCIALMODELITSFOCUSISONIMPROVINGBUDGETING’SSUPPORTOFOPERATIONALPLANNINGTHEEUROPEANBASEDCAMIBEYONDBUDGETINGBBGROUPTAKESAMORERADICALVIEWANDRECOMMENDSATWOSTAGEAPPROACHTHEFIRSTSTAGEADDRESSESTHEPROBLEMSWITHBUDGETINGWHENTHEYAREUSEDFORPERFORMANCEEVALUATIONITSUGGESTSTHATTRADITIONALBUDGETARYCONTROLSTHATCOMBINEPLANNINGANDPERFORMANCEEVALUATIONLEADTOBOTHPOORPLANNINGANDDYSFUNCTIONALBEHAVIORTHEREFORE,THEBBGROUPRECOMMENDSEITHERRADICALLYCHANGINGTRADITIONALBUDGETBASEDPERFORMANCEEVALUATIONSORCOMPLETELYELIMINATINGTHEBUDGETPROCESSTHESECONDSTAGEOFTHEBBAPPROACHISTORADICALLYDECENTRALIZETHEORGANIZATIONANDEMPOWERLOWERLEVELMANAGERSAND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簡介：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/DECEMBER2004/531JBRIDGEENG20049531540DOWNLOADEDFROMASCELIBRARYORGBYUNIVERSITYOFMELB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簡介：字?jǐn)?shù)英文字?jǐn)?shù)英文28402840單詞，單詞，1522315223字符；中文字符；中文50265026漢字漢字出處出處DKDKYAPAYAPAABEYWARDHANACAPITALABEYWARDHANACAPITALSTRUCTURESTRUCTURETHEORYTHEORYANANOVERVIEWJOVERVIEWJACCOUNTINGACCOUNTINGANDANDFINANCEFINANCERESEARCH2017,61133138RESEARCH2017,61133138外文文獻(xiàn)外文文獻(xiàn)CAPITALSTRUCTURETHEORYANOVERVIEWABSTRACTCAPITALSTRUCTUREISSTILLAPUZZLEAMONGFINANCESCHOLARSPURPOSEOFTHISSTUDYISTOREVIEWVARIOUSCAPITALSTRUCTURETHEORIESTHATHAVEBEENPROPOSEDINTHEFINANCELITERATURETOPROVIDECLARIFICATIONFORTHEFIRMS’CAPITALSTRUCTUREDECISIONSTARTINGFROMTHECAPITALSTRUCTUREIRRELEVANCETHEORYOFMODIGLIANIANDMILLER1958THISREVIEWEXAMINETHESEVERALTHEORIESTHATHAVEBEENPUTFORWARDTOEXPLAINTHECAPITALSTRUCTURETHREEMAJORTHEORIESEMERGEDOVERTHEYEARSFOLLOWINGTHEASSUMPTIONOFTHEPERFECTCAPITALMARKETOFCAPITALSTRUCTUREIRRELEVANCEMODELTRADEOFFTHEORYASSUMESTHATFIRMSHAVEONEOPTIMALDEBTRATIOANDFIRMTRADEOFFTHEBENEFITANDCOSTOFDEBTANDEQUITYFINANCINGPECKINGORDERTHEORYMYERS,1984,MYERSANDMAJLUF,1984ASSUMESTHATFIRMSFOLLOWAFINANCINGHIERARCHYWHEREBYMINIMIZETHEPROBLEMOFINFORMATIONASYMMETRYBUTNEITHEROFTHESETWOTHEORIESPROVIDEACOMPLETEDESCRIPTIONWHYSOMEFIRMSPREFERDEBTANDOTHERSPREFEREQUITYFINANCEUNDERDIFFERENTCIRCUMSTANCESANOTHERTHEORYOFCAPITALSTRUCTUREHASINTRODUCEDRECENTLYBY,BAKERANDWURGLER2002,MARKETTIMINGTHEORY,WHICHEXPLAINSTHECURRENTCAPITALSTRUCTUREASTHECUMULATIVEOUTCOMEOFPASTATTEMPTSTOTIMETHEEQUITYMARKETMARKETTIMINGISSUINGBEHAVIOURHASBEENWELLESTABLISHEDEMPIRICALLYBYOTHERSALREADY,BUTBAKERANDWURGLER2002SHOWTHATTHEINFLUENCEOFMARKETTIMINGONCAPITALSTRUCTUREISREGULARANDCONTINUOUSSOTHEPREDICTIONSOFTHESETHEORIESSOMETIMESACTEDINACONTINUOUSLYDECLININGWEIGHTEDAVERAGECOSTOFCAPITALWACCFURTHERTHISAPPROACHASSUMETHECONCEPTOFOPTIMALCAPITALSTRUCTUREANDTHEREBYVERYCLEARLYIMPLIESTHATWACCDECREASESONLYFORACERTAINLEVELOFFINANCIALLEVERAGEANDREACHINGTHEMINIMUMLEVELFURTHERINCREASEINFINANCIALLEVERAGEWOULDINCREASETHEWACCDURINGTHEPASTFIVEDECADESVARIOUSTHEORIESHAVEBEENDEVELOPEDANDTOEXPLAINTHECAPITALSTRUCTUREANDVALUEOFTHEFIRMANDMAINFACTORSDETERMININGCAPITALSTRUCTURESIMULTANEOUSLYENORMOUSNUMBEROFEMPIRICALSTUDIESHAVEALSOTRIEDTOEXPLAINTHESETHEORIESANDTHEIREFFECTIVENESS2CAPITALSTRUCTURETHEORIES21CAPITALSTRUCTUREIRRELEVANCETHEORYOFMODIGLIANIANDMILLERCAPITALSTRUCTUREIRRELEVANCETHEORYOFMODIGLIANIANDMILLER1958ISCONSIDEREDASTHESTARTINGPOINTOFMODERNTHEORYOFCAPITALSTRUCTUREBASEDONASSUMPTIONSRELATEDTOTHEBEHAVIOROFINVESTORSANDCAPITALMARKETMMILLUSTRATESTHATFIRMVALUEISUNAFFECTEDBYTHECAPITALSTRUCTUREOFTHEFIRMSECURITIESARETRADEDINPERFECTCAPITALMARKET,ALLRELEVANTINFORMATIONAREAVAILABLEFORINSIDERSANDOUTSIDERSTOTAKETHEDECISIONNOASYMMETRYOFINFORMATION,THATISTRANSACTIONCOST,BANKRUPTCYCOSTANDTAXATIONDONOTEXISTBORROWINGANDLENDINGISPOSSIBLEFORFIRMSANDINDIVIDUALINVESTORSATTHESAMEINTERESTRATEWHICHPERMITSFORHOMEMADELEVERAGE,FIRMSOPERATINGINASIMILARRISKCLASSESANDHAVESIMILAROPERATINGLEVERAGE,INTERESTPAYABLEONDEBTDONOTSAVEANYTAXESANDFIRMSFOLLOW100DIVIDENDPAYOUTUNDERTHESEASSUMPTIONSMMTHEORYPROVEDTHATTHEREISNOOPTIMALDEBTTOEQUITYRATIOANDCAPITALSTRUCTUREISIRRELEVANTFORTHESHAREHOLDERSWEALTHTHISPREPOSITIONPRESENTEDBYMM1958INTHEIRSEMINALPAPERANDARGUETHATVALUEOFLEVEREDFIRMISSAMEASTHEVALUEOFUNLEVEREDFIRMTHEREFORETHEYPROPOSETHATMANAGERSSHOULDNOTCONCERNTHECAPITALSTRUCTUREANDTHEYCANFREELYSELECTTHE

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STWOSIDESFIRSTLY,ENOUGHRESOURCESMUSTBEINVESTEDTOCREATECOSTADVANTAGEBASEDONCUSTOMERVALUE；SECONDLY,THECONSUMPTIONOFRESOURCESMUSTBEREDUCEDASMUCHASPOSSIBLETOCREATECOSTADVANTAGEBASEDONTHEMAXIMUMBUSINESSVALUESURPLUSORPROFIT．THEREFORE，THECOSTCONTROLFROMTHEWHOLEVIEWOFTHECREATIONANDVALUESUPPLYISACTUALLYAKINDOFCOSTCONTROLWHICHLAYSEQUALSTRESSONBOTHEARNINGINCOMEANDCUTTINGDOWNEXPENSE．3．FUNDAMENTALTHOUGHTOFTHECOSTCONTROLBASEDONVALUECHAINFORBOTHEARNINGMOREINCOMEANDCUTTINGDOWNEXPENSEACCORDINGTOTHETHEORYOFVALUECHAIN，COSTCANBESENASTHERESOURCEOFOBTAININGPROFITSORCREATINGANDSUPPLYINGCUSTOMERVALUE．THUS，EARNINGMOREINCOMECANIMPROVEPROCEEDSANDCUTTINGDOWNEXPENSESCANMAXIMIZETHESEPROCEEDS．THEFORMERLIESINMAKINGITNECESSARYANDENSURINGTHEREISENOUGHINVESTMENTINRESOURCES，ANDTHELATTERDEMANDSENSURINGTHECONTROLOFTHEREASONABLECONSUMPTIONOFRESOURCES．3．1COSTCONTROLBASEDONVALUECHAINFROMEARNINGMOREINCOMECONTROLLINGNECESSARYANDENOUGHRESOURCEINVESTMENTWITHREGARDTOTHECREATIONOFVALUE，THECOSTCONTROLBASEDONVALUECHAINSHOULDFIRSTLYENSURETHEREISENOUGHINVESTMENTINRESOURCES．THENAVALUECHAINSHOULDBECONSTRUCTEDWHICHHASACOMPETITIVEADVANTAGE，I．E．ANINVESTMENTINRESOURCESWHICHPAYSATTENTIONTOHOWTOCREATECORECOMPETENCE．FINALLYTHEVALUECHAINSHOULDBEMADEUNIQUE．THISISCONTRARYTOTHEIDEAOFTRADITIONALCOSTCONTRO1．16維普資訊HTTP//WWWCQVIPCOM

簡介：2150單詞，11800英文字符，3700漢字文獻(xiàn)出處BRUNZELLT,LILJEBLOME,L?FLUNDA,ETALDIVIDENDPOLICYINNORDICLISTEDFIRMSJGLOBALFINANCEJOURNAL,2014,252124135HTTP//WWWWENKU1COM/NEWS/908A20D596840F31HTML原文DIVIDENDPOLICYINNORDICLISTEDFIRMSTOR,EVA,ANDERS,MIKAABSTRACTINTHISPAPERWEANALYZETHERESULTSFROMASURVEYAMONGALLPUBLICLYLISTEDNORDICFIRMSONTHEIRDIVIDENDPAYOUTPOLICYTHERESULTSSHOWTHAT72OFTHENORDICCOMPANIESHAVEASPECIFIEDDIVIDENDPOLICYLARGERANDMOREPROFITABLECOMPANIESAREMORELIKELYTOHAVEADEFINEDDIVIDENDPOLICYINPLACETHEDIVIDENDPOLICYISMOSTLYINFLUENCEDBYCAPITALSTRUCTURECONSIDERATIONSANDTHEOUTLOOKOFFUTUREEARNINGSWEALSOFINDTHATTHELIKELIHOODFORAFIRMHAVINGANEXPLICITDIVIDENDPOLICYISPOSITIVELYRELATEDTOOWNERSHIPCONCENTRATIONASWELLASTOTHEPRESENCEOFLARGELONGTERMPRIVATEORINDUSTRIALOWNERSOURRESULTSSUPPORTTHEUSEOFDEFINEDDIVIDENDPOLICIESFORAGENCYORMONITORINGREASONSRATHERTHANSIGNALINGREASONSKEYWORDSCORPORATEFINANCEDIVIDENDPOLICYPAYOUTNASDAQOMXINTRODUCTIONEVERSINCESTUDIESSUCHASLINTNER1956ANDFAMAANDBABIAK1968,ALARGENUMBEROFPAPERSHAVESTUDIEDCORPORATEDIVIDENDPOLICIESPAYOUTRATIOSANDFACTORSTHATCONTRIBUTETOTHEPAYOUTDECISIONRECENTLY,FOCUSHASBEENONTHECHOICEBETWEENDIVIDENDSANDSHAREREPURCHASESSEEFOREXAMPLEGUAYANDHARFORD,2000ANDJAGANNATHANETAL,2000ANDSKINNER,2008,THEQUESTIONOFDISAPPEARINGDIVIDENDSSEEFOREXAMPLEDEANGELOETAL,2004ANDFAMAANDFRENCH,2001,ANDTHERELATIONSHIPBETWEENMINORITYPROTECTIONANDDIVIDENDSSEEFOREXAMPLEFACCIOETAL,2001ANDLAPORTAETAL,2000TYPICALLY,THEDIVIDENDPAYOUTISFOUNDTOBEAFUNCTIONOFFACTORSSUCHASPROFITABILITYOFTHECOMPANY,STABILITYOFTHEEARNINGS,RATEOFGROWTH,FREECASHFLOWS,ANDMORERECENTLY,THEGOVERNINGSTRUCTUREOFTHECOMPANYINTHEIRSURVEYOFDIVIDENDPOLICIES,DEANGELO,DEANGELOANDSKINNER2008CONCLUDETHATASIMPLENOTPLAYAMAJORROLEAMIHUDGOMES,2000ACCORDINGTOTHISVIEW,FIRMSCANBUILDAREPUTATIONOFGOODTREATMENTOFSHAREHOLDERSDESPITEWEAKERSHAREHOLDERPROTECTIONBYPAYINGOUTDIVIDENDSTHISVIEWSUGGESTSTHATDIVIDENDSTREAMSWOULDBEHIGHERINCOUNTRIESWITHWEAKERSHAREHOLDERPROTECTION

簡介：ANAPPROACHTODETERMINELONGTERMBEHAVIOROFCONCRETEMEMBERSPRESTRESSEDWITHFRPTENDONSSAMERAYOUAKIM,VISTASPMKARBHARIDEPARTMENTOFSTRUCTURALENGINEERING,MC0085,UNIVERSITYOFCALIFORNIA,SANDIEGO,LAJOLLA,CA920930085,USARECEIVED8AUGUST2005RECEIVEDINREVISEDFORM23JANUARY2006ACCEPTED6FEBRUARY2006AVAILABLEONLINE6MAY2006ABSTRACTTHECOMBINEDEFFECTSOFCREEPANDSHRINKAGEOFCONCRETEANDRELAXATIONOFPRESTRESSINGTENDONSCAUSEGRADUALCHANGESINTHESTRESSESINBOTHCONCRETEANDPRESTRESSINGTENDONSASIMPLEMETHODISPRESENTEDTOCALCULATETHELONGTERMPRESTRESSLOSSANDTHELONGTERMCHANGEINCONCRETESTRESSESINCONTINUOUSPRESTRESSEDCONCRETEMEMBERSWITHEITHERCARBONFIBERREINFORCEDPOLYMERCFRPORARAMIDFIBERREINFORCEDPOLYMERAFRPTENDONSTHEMETHODSATISFIESTHEREQUIREMENTSOFEQUILIBRIUMANDCOMPATIBILITYANDAVOIDSTHEUSEOFANYEMPIRICALMULTIPLIERSASIMPLEGRAPHISPROPOSEDTOEVALUATETHEREDUCEDRELAXATIONINAFRPTENDONSITISSHOWNTHATTHEPRESTRESSLOSSINFRPTENDONSISSIGNIFICANTLYLESSTHANTHATWHENUSINGPRESTRESSINGSTEEL,MAINLYBECAUSEOFTHELOWERMODULIOFELASTICITYOFFRPTENDONSTHELONGTERMCHANGESINCONCRETESTRESSESANDDEFLECTIONCANBEEITHERSMALLERORGREATERTHANTHOSEOFCOMPARABLEGIRDERSPRESTRESSEDWITHSTEELTENDONS,DEPENDINGONTHETYPEOFFRPTENDONSANDTHEINITIALSTRESSPROFILEOFTHECROSSSECTIONUNDERCONSIDERATION?2006ELSEVIERLTDALLRIGHTSRESERVEDKEYWORDSCREEPFRPLONGTERMPRESTRESSLOSSPRESTRESSEDCONCRETERELAXATIONSHRINKAGE1INTRODUCTIONTHEUSEOFFIBERREINFORCEDPOLYMERFRPTENDONSASPRESTRESSINGREINFORCEMENTSHAVEBEENPROPOSEDINTHEPASTDECADEANDAFEWCONCRETEBRIDGESHAVEALREADYBEENCONSTRUCTEDUTILIZINGFIBERREINFORCEDPOLYMERFRPTENDONSCOMPAREDTOCONVENTIONALSTEELPRESTRESSINGTENDONS,FRPTENDONSHAVEMANYADVANTAGES,INCLUDINGTHEIRNONCORROSIVEANDNONCONDUCTIVEPROPERTIES,LIGHTWEIGHT,ANDHIGHTENSILESTRENGTHMOSTOFTHERESEARCHCONDUCTEDONCONCRETEGIRDERSPRESTRESSEDWITHFRPTENDONSHASFOCUSEDONTHESHORTTERMBEHAVIOROFPRESTRESSEDMEMBERSRESEARCHFINDINGSONTHELONGTERMBEHAVIOROFCONCRETEMEMBERSWITHFRPTENDONSARESCARCEINTHELITERATURETHERECENTACICOMMITTEEREPORTONPRESTRESSINGCONCRETESTRUCTURESWITHFRPTENDONSACI4404R041HASPOINTEDOUTTHAT‘‘RESEARCHONTHELONGTERMLOSSOFPRESTRESSANDTHERESULTANTTIMEDEPENDENTCAMBER/DEFLECTIONISNEEDED’’MOSTOFTHERESEARCHANDAPPLICATIONSOFFRPTENDONSINCONCRETESTRUCTURESHAVEADOPTEDEITHERCARBONFIBERREINFORCEDPOLYMERCFRPORARAMIDFIBERREINFORCEDPOLYMERAFRPTENDONSTHEUSEOFGLASSFIBERREINFORCEDPOLYMERSGFRPHASMOSTLYBEENLIMITEDTOCONVENTIONALREINFORCINGBARSDUETOTHEIRRELATIVELYLOWTENSILESTRENGTHANDPOORRESISTANCETOCREEPTHEREFORE,THISPAPERFOCUSESONPRESTRESSEDMEMBERSWITHEITHERCFRPORAFRPTENDONSCREEPANDSHRINKAGEOFCONCRETE,ANDRELAXATIONOFPRESTRESSINGTENDONS,CAUSELONGTERMDEFORMATIONSINCONCRETESTRUCTURESWHILEITISGENERALLYACCEPTEDTHATLONGTERMLOSSESDONOTAFFECTTHEULTIMATECAPACITYOFAPRESTRESSEDCONCRETEMEMBER,AREASONABLYACCURATEPREDICTIONOFTHESELOSSESISIMPORTANTTOENSURESATISFACTORYPERFORMANCEOFCONCRETESTRUCTURESINSERVICEIFPRESTRESSLOSSESAREUNDERESTIMATED,THETENSILESTRENGTHOFCONCRETECANBEEXCEEDEDUNDERFULLSERVICELOADS,CAUSINGCRACKINGANDUNEXPECTEDEXCESSIVEDEFLECTIONONTHEOTHERHAND,OVERESTIMATING09500618/SEEFRONTMATTER?2006ELSEVIERLTDALLRIGHTSRESERVEDDOI101016/JCONBUILDMAT200602006CORRESPONDINGAUTHORTEL18585346470FAX18585346373EMAILADDRESSVKARBHARIUCSDEDUVMKARBHARIWWWELSEVIERCOM/LOCATE/CONBUILDMATCONSTRUCTIONANDBUILDINGMATERIALS2120071052–1060CONSTRUCTIONANDBUILDINGMATERIALSWHEREKRP1/FPURP1ISTHESTRESSINTHETENDON1HAFTERSTRESSRELEASERATIOSOFRP1/RP0INTHEIRTESTSVARIEDBETWEEN091AND096,WITHANAVERAGEOF093TABULATEDVALUESOFTHEVARIABLESAANDBWEREPROVIDEDFORK04ANDK06,ANDFORDIFFERENTTEMPERATURELEVELSANDSOLUTIONTYPESFORAFRPTENDONSINAIRATATEMPERATUREOF25?C,RELATIONSHIPSFORAANDBWEREPROPOSED2ASA?K?003B?K?02723D2TINAPRESTRESSEDCONCRETEMEMBER,THETWOENDSOFTHEPRESTRESSINGTENDONCONSTANTLYMOVETOWARDEACHOTHERBECAUSEOFCREEPANDSHRINKAGEOFCONCRETE,THEREBYREDUCINGTHETENSILESTRESSINTHETENDONTHISREDUCTIONINTENSIONHASASIMILAREFFECTTOTHATWHENTHETENDONISSUBJECTEDTOALESSERINITIALSTRESSTHUS,AREDUCEDRELAXATIONVALUE,D?RPR,SHOULDBEUSEDINTHEANALYSISOFLONGTERMEFFECTSINPRESTRESSEDMEMBERS,SUCHTHATD?RPR?VRDRPRD3TWHEREVRISADIMENSIONLESSCOEFFICIENTLESSTHANUNITYFOLLOWINGANAPPROACHPREVIOUSLYSUGGESTEDBYGHALIANDTREVINO3TOEVALUATEVRFORPRESTRESSINGSTEELTENDONS,VRFORAFRPTENDONSCANBECALCULATEDASLOGTINEQ1ISTAKENEQUALTO5FOR100,000HVR?Z10KD1?XFT?DA0?5B0TD1?XFTDK?DA?5BTTDFD4TWHEREA0?KD1?XFT?003B0?KD1?XFT?02723D5TANDFISADIMENSIONLESSTIMEFUNCTIONDEFININGTHESHAPEOFTHETENDONSTRESS–TIMECURVETHEVALUEOFFINCREASESFROM0TO1ASTIMECHANGESFROMINITIALPRESTRESSTIMET0TOFINALTIMETXISTHERATIOOFTHEDIFFERENCEBETWEENTHETOTALPRESTRESSLOSSDRPSTANDINTRINSICRELAXATIONDRPRTTOTHEINITIALSTRESSRP0,EXPRESSEDASX??DRPSDTT?DRPRDTTRP0D6TFIG1SHOWSTHEVARIATIONOFVRWITHXFORRP0/FPU04,05,AND06,WHICHREPRESENTSTHECOMMONVALUESOFINITIALPRESTRESSINGRATIOS1ASWILLBESHOWNINALATERSECTION,XTYPICALLYVARIESBETWEEN01AND02ANDAVALUEOFVR095CANBEASSUMEDFORPRACTICALPURPOSES3PROPOSEDMETHODOFANALYSISTHEANALYSISFOLLOWSTHEFOURGENERICSTEPSPROPOSEDBYGHALIETAL4ANDDEPICTEDSCHEMATICALLYINFIG2THEPROCEDURECANBEDEVELOPEDCONSIDERINGANARBITRARY0850909510010203RP0/FPU060504FIG1REDUCEDRELAXATIONCOEFFICIENTVRFORAF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