簡(jiǎn)介：DEEPENINGTHEWRECKOFTHEASSIEUROLINKBYUSINGTHETRAILINGSUCTIONHOPPERDREDGERPRINSDERNEDERLANDENBJACOBS1ABSTRACTINJANUARY2003THEFREIGHTSHIPASSIEUROLINKSANKAFTERACOLLISION,48NMOFFTHENORTHCOASTOFTHENETHERLANDSASTHEWRECKWASLOCATEDINABUSYSHIPPINGLANEITHADTOBEEITHERREMOVEDORLOWEREDBELOWTHEGUARANTEEDNAVIGABLEDEPTHOF29MAFTERTAKINGCOSTANDFEASIBILITYINTOCONSIDERATIONRIJKSWATERSTAATDUTCHMARITIMEAUTHORITIESDECIDEDTOHAVETHEASSIEUROLINKLOWEREDBYDREDGINGTHEEXISTINGSEABOTTOMMATERIALAROUNDTHEWRECKDURINGTHESECONDHALFOF2003RIJKSWATERSTAATANDBOSKALISDEVELOPEDTHEDREDGINGOPTIONTHECOMBINATIONOFSITECONDITIONSMADETHEOPERATIONADREDGINGCHALLENGE,SINCEITHADNEVERBEENEXECUTEDBEFOREUNDERTHESECONDITIONSFIRSTTHELOCATIONOFTHEWRECKWASUNFAVORABLEFORWORKINGCONDITIONS,DUETOTHEOPENSEAENVIRONMENT,VERYBUSYSHIPPINGANDTHEDEPTHOFTHESEABOTTOM,WHICHWASALMOST45MTHESECONDITIONSLEADTOTHECHOICEOFAMODERN,VERSATILEANDHIGHLYMANOEUVERABLETRAILINGSUCTIONHOPPERDREDGER,BEINGABLETODREDGEUPTO80MSECONDTHESOILPROPERTIESPLAYEDANIMPORTANTROLE,SINCETHEMATERIALHADTOFLOWFROMUNDERNEATHTHEASSIEUROLINKAFTERDREDGINGAHOLEAROUNDTHEWRECK’SHULLTHIRDTHEASSIEUROLINKHADBROKENUPINTOTWOPARTSANDSOMESECTIONSHADEVENCOLLAPSEDTHERISKOFDAMAGINGOREVENLOSINGTHESUCTIONPIPE,BYUNCONTROLLEDMOVEMENTSOFWRECKAGEWASHIGHTOENSUREASAFEOPERATIONAMONITORINGSYSTEMWITHMOTIONSENSORSWASINSTALLEDONTHEWRECK,WHICHREGISTEREDSUDDENMOVEMENTSANDGAVEAWARNINGSINCETHEGOALOFTHEPROJECTWASTOLOWERTHEWRECKBELOWTHEREQUIREDNAVIGABLEDEPTHANEFFORTHASBEENMADETOCONTINUOUSLYMONITORTHEEXACTLOCATIONBYUSINGANULTRASHORTBASELINEUSBLSYSTEMASAPARTOFTHESYSTEMSEVERALACOUSTICSENSORSWEREFITTEDONTHEWRECK,PRIORTODREDGINGOPERATIONSKEYWORDSWRECK,DEEPENING,DREDGING1DREDGINGDEPARTMENT,ROYALBOSKALISWESTMINSTER,ROSMOLENWEG20,POBOX43,3350AAPAPENDRECHT,THENETHERLANDS,EMAILBJACOBSBOSKALISNL7MMEDIUMTOCOARSE,VERYDENSESANDPLEISTOCENEEEMMOLENGATFORMATIONHARDCLAYPLEISTOCENECLEVERBANKFORMATIONTHERESULTSFROMTHESOILINVESTIGATIONPROVIDEDSUFFICIENTINFORMATIONTOANSWERQUESTIONSCONCERNINGDREDGEBILITYOFTHEMATERIALWITHEXISTINGDREDGINGEQUIPMENTSLOPEDEVELOPMENTOFTHEMATERIALUNDERNEATHTHEWRECKPOSSIBLEEXCAVATIONDEPTHTOCREATETHEREQUIREDBUFFERTOSUFFICIENTLYSINKTHEWRECKPARTS3EQUIPMENTCHOICEAFTERSTUDYINGTHEBOUNDARYCONDITIONSITWASDECIDEDTOUSETHEBRANDNEW16,000M3TRAILINGSUCTIONHOPPERDREDGER“PRINSDERNEDERLANDEN”,BECAUSEOFTHEADVANTAGEOUSCHARACTERISTICSFORTHEEXECUTIONOFTHEPROJECTSUFFICIENTDEPTHRANGETHEVESSELISEQUIPPEDWITHONESTANDARDSUCTIONPIPELAYOUT,BEINGABLETODREDGEUPTO55MDEPTHANDONEDEEPDREDGINGLAYOUTFORAWORKINGDEPTHOF83MFURTHERMORETHEDEEPDREDGINGLAYOUTCONTAINSANUNDERWATERPUMP,GIVINGMOREFLEXIBILITYANDAHIGHERPRODUCTIONOUTPUTWHENWORKINGINWATERDEPTHSOFMORETHAN30MALOTOFINSTALLEDJETPOWERUPTO3,000KWASTHEPLEISTOCENESANDLAYERWASCONSIDEREDTOBEVERYDENSELYPACKEDITWASFORESEENTHATTHESLOPEDEVELOPMENTNEEDEDTOBEACTIVATEDBYMEANSOFJETTINGGOODMANOEUVRABILITYCHARACTERISTICS,MAKINGTHEVESSELMOSTSUITABLEFORWORKINGINARESTRICTEDAREAANDANTICIPATEONPOSSIBLESHIPTRAFFICPASSINGTHESITEBEINGABLETOOPERATEATWAVEHEIGHTSUPTO3M,WHICHWASCONSIDEREDAVERYIMPORTANTISSUEWHENWORKINGINAPRILONTHENORTHSEAINOFFSHORECONDITIONSEQUIPPEDWITHDYNAMICPOSITIONINGDPANDDYNAMICTRACKINGDT,GIVINGTHEPOSSIBILITYTOWORKVERYACCURATELYTHEVESSELBEINGSELFPROPELLEDANDTHEREFORESUITABLETOEVENLYSPREADITSLOADOVERTHESEABOTTOMATANYGIVENDISTANCE,WITHOUTBEINGANOBSTACLEINTHESHIPPINGLANE4RISKSFROMALLTHEAVAILABLESOILINFORMATIONITWASCONCLUDEDTHATTHEPLEISTOCENESANDLAYERWASSTRONGLYOVERCONSOLIDATEDDUETOANANCIENTGLACIALICECOVERSLOPESINTHEEXCAVATEDTRENCHWEREEXPECTEDTOREMAINSTEEPDUETOTHESOILBEHAVIOUR,WHICHWOULDPREVENTTHESANDFLOWINGFROMUNDERNEATHTHEWRECKINANATURALWAYCALCULATIONSSHOWEDTHATATLEASTAHOLEOF10MWOULDBENECESSARYTOCREATESUFFICIENTSLOPEDEVELOPMENTTOHAVETHEWRECKSLIDINGONITSOWNWEIGHTINTOTHEDREDGEDTRENCHATAPPROXIMATELY10MHOWEVERTHEREWASTHERISKOFENCOUNTERINGAHARDCLAYOFTHECLEAVERFORMATION,WHICHWASEXPECTEDTOHAVEANEGATIVEEFFECTONTHEFORMATIONOFASLIPCIRCLE,THUSPREVENTINGSUFFICIENTSLOPEDEVELOPMENTTOOVERCOMETHEHIGHSOILRISKS,ASPECIALJETTINGDEVICEWASDEVELOPEDTOACTIVATETHESLOPEDEVELOPMENTBYJETWATERFORCEFORTHISPURPOSE,THEJETCONSISTEDOFTWOSIDENOZZLESANDANOZZLEDIRECTEDBACKWARDTHEDEVICECOULDBEMOUNTEDONTHESUCTIONTUBEOFTHETRAILINGSUCTIONHOPPERDREDGERANDATOTALPOWEROF5,500KWWASAVAILABLEFROMONEDREDGEPUMPANDTHREEJETPUMPSASECONDOPTIONTOCREATESUFFICIENTINSTABILITYOFTHESANDLAYERUNDERNEATHTHEWRECKWASTODREDGEASECONDTRENCHONTHEOPPOSITESIDELARGEPIECESOFDEBRIS,POSSIBLESCATTEREDAROUNDTHEWRECKONTHESEABOTTOMCAUSINGDAMAGEONTHESUCTIONPIPECOULDSTAGNATETHEWHOLEOPERATIONTHEREFORESPECIALFOCUSWASMADEONLOCATINGTHESEPIECESTHISWASDONEBYROVINSPECTION,BEFORETHEDREDGINGOPERATIONSSTARTEDANDDURINGTHESTARTOFTHEPROJECTBYSOCALLEDRECONNAISSANCEDREDGINGRECONNAISSANCEDREDGINGCONTAINEDPREDREDGINGBYCOVERINGTHECOMPLETEAREAAROUNDTHEWRECKWITHONEPIPE,USINGTHESTANDARDPIPELINELAYOUTSINCETHISLAYOUTWOULDNOTBEUSEDDURINGTHEREMAININGDREDGINGOPERATIONS,DAMAGEONTHEPIPEORDRAGHEADWOULDNOTJEOPARDIZETHEPROJECTPLANNINGKNOWINGTHEEXACTPOSITIONANDMONITORINGTHEBEHAVIOUROFTHEWRECKDURINGTHEOPERATIONWASCONSIDEREDESSENTIAL,ASONEOFTHEOBJECTIVESWASTOSINKTHEWRECKPARTSINACONTROLLEDWAYANDFORSAFETYOFTHEDREDGINGOPERATIONESPECIALLYTHESPEEDATWHICHTHEWRECKMOVEDANDTHEWAYITCHANGEDPOSITION,BYMEANSOFSLIDING

簡(jiǎn)介：DESIGNOFTHETEMPERATURECONTROLSYSTEMBASEDONAT89S51DRLEONGAILLARDHEADOFRESEARCH,LAOINSTITUTEFORRENEWABLEENERGYLIRE,SOKPALUANGROAD,SOKPALUANGVILLAGE,VIENTIANE,LAOPDR,POBOX8010ABSTRACTTHEPRINCIPLEANDFUNCTIONSOFTHETEMPERATURECONTROLSYSTEMBASEDONMICROCONTROLLERAT89S51ARESTUDIED,ANDTHETEMPERATUREMEASUREMENTUNITCONSISTSOFTHE1WIREBUSDIGITALTEMPERATURESENSORDS18B20THESYSTEMCANBEEXPECTEDTODETECTTHEPRESETTEMPERATURE,DISPLAYTIMEANDSAVEMONITORINGDATAANALARMWILLBEGIVENBYSYSTEMIFTHETEMPERATUREEXCEEDSTHEUPPERANDLOWERLIMITVALUEOFTHETEMPERATUREWHICHCANBESETDISCRETIONARILYANDTHENAUTOMATICCONTROLISACHIEVED,THUSTHETEMPERATUREISACHIEVEDMONITORINGINTELLIGENTLYWITHINACERTAINRANGEBASINGONPRINCIPLEOFTHESYSTEM,ITISEASYTOMAKEAVARIETYOFOTHERNONLINEARCONTROLSYSTEMSSOLONGASTHESOFTWAREDESIGNISREASONABLYCHANGEDTHESYSTEMHASBEENPROVEDTOBEACCURATE,RELIABLEANDSATISFIEDTHROUGHFIELDPRACTICEKEYWORDSAT89S511MICROCONTROLLER2DS18B203TEMPERATURE4IINTRODUCTIONTEMPERATUREISAVERYIMPORTANTPARAMETERINHUMANLIFEINTHEMODERNSOCIETY,TEMPERATURECONTROLTCISNOTONLYUSEDININDUSTRIALPRODUCTION,BUTALSOWIDELYUSEDINOTHERFIELDSWITHTHEIMPROVEMENTOFTHELIFEQUALITY,WECANFINDTHETCAPPLIANCEINHOTELS,FACTORIESANDHOMEASWELLANDTHETRENDTHATTCWILLBETTERSERVETHEWHOLESOCIETY,SOITISOFGREATSIGNIFICANCETOMEASUREANDCONTROLTHETEMPERATUREBASEDONTHEAT89S51ANDTEMPERATURESENSORDS18B20,THISSYSTEMCONTROLSTHECONDITIONTEMPERATUREINTELLIGENTLYTHETEMPERATURECANBESETDISCRETIONARILYWITHINACERTAINRANGETHESYSTEMCANSHOWTHETIMEONLCD,ANDSAVEMONITORINGDATAANDAUTOMATICALLYCONTROLTHETEMPERATUREWHENTHECONDITIONTEMPERATUREEXCEEDSTHEUPPERANDLOWERLIMITVALUEBYDOINGSOITISTOKEEPTHETEMPERATUREUNCHANGEDTHESYSTEMISOFHIGHANTIJAMMING,HIGHCONTROLPRECISIONANDFLEXIBLEDESIGNITALSOFITSTHERUGGEDENVIRONMENTITISMAINLYUSEDINPEOPLESLIFETOIMPROVETHEQUALITYOFTHEWORKANDLIFEITISALSOVERSATILE,SOTHATITCANBECONVENIENTTOEXTENDTHEUSEOFTHESYSTEMSOTHEDESIGNISOFPROFOUNDIMPORTANCETHEGENERALDESIGN,HARDWAREDESIGNANDSOFTWAREDESIGNOFTHESYSTEMARECOVEREDIISYSTEMGENERALDESIGNTHEHARDWAREBLOCKDIAGRAMOFTHETCISSHOWNINFIG1THESYSTEMHARDWAREINCLUDESTHEMICROCONTROLLER,TEMPERATUREDETECTIONCIRCUIT,KEYBOARDCONTROLCIRCUIT,CLOCKCIRCUIT,DISPLAY,ALARM,DRIVECIRCUITANDEXTERNALRAMBASEDONTHEAT89S51,THEDS18B20WILLTRANSFERTHETEMPERATURESIGNALDETECTEDTODIGITALSIGNALANDTHESIGNALISSENTTOTHEMICROCONTROLLERFORPROCESSINGATLASTTHETEMPERATUREVALUEISSHOWEDONTHELCD12232FTHESESTEPSAREUSEDTOACHIEVETHETEMPERATUREDETECTIONUSINGTHEKEYBOARDINTERFACECHIPHD7279TOSETTHETEMPERATUREVALUE,USINGTHEMICROCONTROLLERTOKEEPACERTAINTEMPERATURE,ANDUSINGTHELCDTOSHOWTHEPRESETVALUEFORCONTROLLINGTHETEMPERATUREINADDITION,THECLOCKCHIPDS1302ISUSEDTOSHOWTIMEANDTHEEXTERNALRAM6264ISUSEDTOSAVETHEMONITORINGDATAANALARMWILLBEGIVENBYBUZZERINTIMEIFTHETEMPERATUREEXCEEDSTHEUPPERANDLOWERLIMITVALUEOFTHETEMPERATUREAT89S51DS18B20KEYBOARDCONTROLCIRCUITFIGURE1HARDWAREBLOCKDIAGRAMIIIHARDWAREDESIGNAMICROCONTROLLERTHEAT89S51ISALOWPOWER,HIGHPERFORMANCECMOS8BITMICROCONTROLLERWITH4KBYTESOFINSYSTEMPROGRAMMABLEFLASHMEMORYTHEDEVICEISMANUFACTUREDUSINGATMEL’SHIGHDENSITYNONVOLATILEMEMORYTECHNOLOGYANDISCOMPATIBLEWITHTHEINDUSTRYSTANDARD80C51INSTRUCTIONSETANDPINOUTTHEONCHIPFLASHALLOWSTHEPROGRAMMEMORYTOBEREPROGRAMMEDINSYSTEMORBYACONVENTIONALNONVOLATILEMEMORYPROGRAMMERBYCOMBININGAVERSATILE8BITCPUWITHINSYSTEMPROGRAMMABLEFLASHONAMONOLITHICCHIP,THEATMELAT89S51ISAPOWERFULMICROCONTROLLERWHICHPROVIDESAHIGHLYFLEXIBLEANDCOSTEFFECTIVESOLUTIONTOMANYEMBEDDEDCONTROLAPPLICATIONSMINIMUMSYSTEMOFTHEMICROCONTROLLERISSHOWNINFIG2INORDERTOSAVEMONITORINGDATA,THE6264ISUSEDASANEXTERNALRAMITISASTATICRAMCHIP,LOWPOWERWITH8KBYTESMEMORYBTEMPERATUREDETECTIONCIRCUITTHETEMPERATURESENSORISTHEKEYPARTINTHESYSTEMTHEDALLASDS18B20ISUSED,WHICHSUPPORTSTHE1WIREBUSINTERFACE,ANDTHEONBOARDPATENTEDISUSEDINTERNALLYALLTHESENSORPARTSANDTHECONVERTINGCIRCUITAREINTEGRATEDININTEGRATEDCIRCUITLIKEATRANSISTOR1ITSMEASURERANGEIS55125,ANDTHEPRECISIONBETWEEN℃℃1085IS℃℃DRIVECIRCUITALARMCIRCUITLCDCIRCUITCLOCKCIRCUITEXTERNALRAM2010INTERNATIONALFORUMONINFORMATIONTECHNOLOGYANDAPPLICATIONS9780769541150/102600?2010IEEEDOI101109/IFITA2010209632010INTERNATIONALFORUMONINFORMATIONTECHNOLOGYANDAPPLICATIONS9780769541150/102600?2010IEEEDOI101109/IFITA201020963ISCONNECTEDTOTHEKEYBOARDANDDISPLAYWITHOUTUSINGANYACTIVEDEVICEACCORDINGTOTHEBASICREQUIREMENTSANDFUNCTIONSOFTHESYSTEM,ONLY6BUTTONSARENEEDEDTHESYSTEMSFUNCTIONSARESETBYTHEAT89S51RECEIVINGTHEENTEREDDATAINORDERTOSAVETHEEXTERNALRESISTOR,THE16KEYBOARDISUSED,ANDTHEKEYBOARDCODESAREDEFINEDAS07H,0FH,17H,1FH,27H,2FHTHEORDERCANBEREADOUTBYREADINGTHECODEINSTRUCTIONHD7279AISCONNECTEDTOTHEAT89S51INSERIALMODEANDONLY4PORTSARENEEDASSHOWNINFIG6,DIG0DIG5ANDDPARERESPECTIVELYTHECOLUMNLINESANDROWLINEPORTSOFTHESIXKEYSWHICHACHIEVEKEYBOARDMONITORING,DECODINGANDKEYCODESIDENTIFICATIONFIGURE6KEYBOARDCONTROLCIRCUITFALARMCIRCUITINORDERTOSIMPLIFYTHECIRCUITANDCONVENIENTDEBUGGING,A5VAUTOMATICBUZZERISUSEDINTHEALARMCIRCUIT8ANDTHISMAKETHESOFTWAREPROGRAMMINGSIMPLIFIEDASSHOWNINFIG7,ITISCONTROLLEDBYTHEPNPTRANSISTOR9012WHOSEBASEISCONNECTEDTOTHEPINP25OFTHEAT89S51WHENTHETEMPERATUREEXCEEDSTHEUPPERANDLOWERLIMITVALUE,THEP25OUTPUTLOWLEVELWHICHMAKESTHETRANSISTORBEONANDTHENANALARMISGIVENBYTHEBUZZERFIGURE7ALARMCIRCUITGDRIVECIRCUITASTEPMOTORISUSEDASTHEDRIVEDEVICETOCONTROLTHETEMPERATURETHEFOURPHASEANDEIGHTBEATPULSEDISTRIBUTIONMODEISUSEDTODRIVEMOTORANDTHESIMPLEDELAYPROGRAMISUSEDTOHANDLETHETIMEINTERVALBETWEENTHEPULSESTOOBTAINDIFFERENTROTATIONALSPEEDTHEREARETWOOUTPUTSTATESFORTHESTEPMOTORONEWHENTHETEMPERATUREISOVERTHEUPPERVALUE,THEMOTORROTATESREVERSELYTOLOWTHETEMPERATURE,WHILEWHENLOWERTHANTHELOWERLIMITVALUE,THEMOTORROTATESNORMALLYTORAISETHETEMPERATUREBESIDESNOTEQUALSTHEPRESETVALUETWOWHENTHETEMPERATUREISATSOMEWHEREBETWEENTHETWOENDSANDEQUALSTHEPRESETVALUE,THEMOTORSTOPSTHESESTEPSAREUSEDTOACHIEVETHETEMPERATURECONTROLINADDITION,THEMOTORSPEEDCANALSOBEADJUSTEDBYRELATIVEBUTTONSASSHOWNINFIG8,THECODEDATAISINPUTTHROUGHPORTSA11A8BEP23P20OFTHEAT89S51ANDINVERTEDOUTPUTBYTHEINVERTER74LS04FINALLYITISAMPLIFIEDBYTHEPOWERAMPLIFIER2803ATOPOWERTHEMOTORFIGURE8DRIVECIRCUITIVSOFTWAREDESIGNACCORDINGTOTHEGENERALDESIGNREQUIREMENTANDHARDWARECIRCUITPRINCIPLEOFTHESYSTEM,ASWELLASTHEIMPROVEMENTOFTHEPROGRAMREADABILITY,TRANSFERABILITYANDTHECONVENIENTDEBUGGING,THESOFTWAREDESIGNISMODULARIZEDTHESYSTEMFLOWMAINLYINCLUDESTHEFOLLOWING8STEPSPOSTPOWERONSELFTEST,SYSTEMINITIATION,TEMPERATUREDETECTION,ALARMHANDLING,TEMPERATURECONTROL,CLOCKCHIPDS1302OPERATION,LCDANDKEYBOARDOPERATIONTHEMAINPROGRAMFLOWISSHOWNINFIG9GIVEALITTLEANALYSISTOTHEABOVE8TASKS,ITISEASYTOFINDOUTTHATTHELASTFIVETASKSREQUIRETHEREALTIMEOPERATIONBUTTOTHETEMPERATUREDETECTIONITCANBEACHIEVEDWITHTIMER0TIMING1SECOND,THATISTOSAYTEMPERATUREDETECTIONOCCURSPERSECONDTHESYSTEMINITIATIONINCLUDESGLOBALVARIABLEDEFINITION,RAMINITIATION,SPECIALFUNCTIONREGISTERINITIATIONANDPERIPHERALEQUIPMENTINITIATIONGLOBALVARIABLEDEFINITIONMAINLYFINISHESTHEINTERFACEDEFINITIONOFEXTERNALINTERFACECHIPCONNECTEDTOTHEAT89S51,ANDSPECIALDEFINITIONOFSOMEMEMORYUNITSRAMINITIATIONMAINLYREFERSTORAMPROCESSINGFOREXAMPLEWHENTHESYSTEMISELECTRIFIEDTHETIMECODEWILLBESTOREDINTHEINTERNALUNITADDRESSORTHESCINTILLATIONFLAGWILLBECLEAREDTHESPECIALFUNCTIONREGISTERINITIATIONINCLUDESLOADINGTHEINITIALVALUEOFTIMERANDOPENINGTHEINTERRUPTFOREXAMPLE,WHENTHESYSTEMISELECTRIFIEDTHETIMERISINITIALIZEDTHEPERIPHERALEQUIPMENTINITIATIONREFERSTOSETTHEINITIALVALUEOFPERIPHERALEQUIPMENTFOREXAMPLE,WHENTHESYSTEMISELECTRIFIED,THELCDSHOULDBEINITIALIZED,THESTARTUPDISPLAYSHOULDBECALLED,THETEMPERATURECONVERSIONCOMMANDSHOULDBEISSUEDFIRSTLYANDTHECLOCKCHIPDS1302SHOULDALSOBEINITIALIZEDTHEALARMHANDLINGISMAINLYTHELOWERINGANDTHERAISINGOFTEMPERATURETOMAKETHETEMPERATUREREMAINWITHTHEPRESETRANGEWHENTHETEMPERATUREISBETWEENTHEUPPERANDTHELOWERLIMITVALUE,ITGOESTOTEMPERATURECONTROLHANDLING,THATISTOSAYTHETEMPERATURENEEDTOBERAISEDORLOWEREDACCORDINGTOTHEPRESETVALUEBYDOINGSOMAKETHE6565

簡(jiǎn)介：DOI101007/S0017000423279ORIGINALARTICLEINTJADVMANUFTECHNOL20062853–60HUAMINZHOUDEQUNLIINTEGRATEDSIMULATIONOFTHEINJECTIONMOLDINGPROCESSWITHSTEREOLITHOGRAPHYMOLDSRECEIVED5MARCH2004/ACCEPTED5JULY2004/PUBLISHEDONLINE6APRIL2005?SPRINGERVERLAGLONDONLIMITED2005ABSTRACTFUNCTIONALPARTSARENEEDEDFORDESIGNVERIFICATIONTESTING,FIELDTRIALS,CUSTOMEREVALUATION,ANDPRODUCTIONPLANNINGBYELIMINATINGMULTIPLESTEPS,THECREATIONOFTHEINJECTIONMOLDDIRECTLYBYARAPIDPROTOTYPINGRPPROCESSHOLDSTHEBESTPROMISEOFREDUCINGTHETIMEANDCOSTNEEDEDTOMOLDLOWVOLUMEQUANTITIESOFPARTSTHEPOTENTIALOFTHISINTEGRATIONOFINJECTIONMOLDINGWITHRPHASBEENDEMONSTRATEDMANYTIMESWHATISMISSINGISTHEFUNDAMENTALUNDERSTANDINGOFHOWTHEMODIFICATIONSTOTHEMOLDMATERIALANDRPMANUFACTURINGPROCESSIMPACTBOTHTHEMOLDDESIGNANDTHEINJECTIONMOLDINGPROCESSINADDITION,NUMERICALSIMULATIONTECHNIQUESHAVENOWBECOMEHELPFULTOOLSOFMOLDDESIGNERSANDPROCESSENGINEERSFORTRADITIONALINJECTIONMOLDINGBUTALLCURRENTSIMULATIONPACKAGESFORCONVENTIONALINJECTIONMOLDINGARENOLONGERAPPLICABLETOTHISNEWTYPEOFINJECTIONMOLDS,MAINLYBECAUSETHEPROPERTYOFTHEMOLDMATERIALCHANGESGREATLYINTHISPAPER,ANINTEGRATEDAPPROACHTOACCOMPLISHANUMERICALSIMULATIONOFINJECTIONMOLDINGINTORAPIDPROTOTYPEDMOLDSISESTABLISHEDANDACORRESPONDINGSIMULATIONSYSTEMISDEVELOPEDCOMPARISONSWITHEXPERIMENTALRESULTSAREEMPLOYEDFORVERIFICATION,WHICHSHOWTHATTHEPRESENTSCHEMEISWELLSUITEDTOHANDLERPFABRICATEDSTEREOLITHOGRAPHYSLMOLDSKEYWORDSINJECTIONMOLDINGNUMERICALSIMULATIONRAPIDPROTOTYPING1INTRODUCTIONININJECTIONMOLDING,THEPOLYMERMELTATHIGHTEMPERATUREISINJECTEDINTOTHEMOLDUNDERHIGHPRESSURE1THUS,THEMOLDMATERIALNEEDSTOHAVETHERMALANDMECHANICALPROPERTIESCAPABLEOFWITHSTANDINGTHETEMPERATURESANDPRESSURESOFTHEMOLDINGCYCLETHEFOCUSOFMANYSTUDIESHASBEENTOCREATETHEHZHOUUDLISTATEKEYLABOFMOLDU,VARETHEAVERAGEWHOLEGAPTHICKNESSESANDΗ,Ρ,CPT,KTREPRESENTVISCOSITY,DENSITY,SPECIFICHEATANDTHERMALCONDUCTIVITYOFPOLYMERMELT,RESPECTIVELYINADDITION,BOUNDARYCONDITIONSINTHEGAPWISEDIRECTIONCANBEDEFINEDASUWV0,TTWATZB5?U?Z0?V?Z,?T?Z0,W0ATZ06WHERETWISTHECONSTANTWALLTEMPERATURESHOWNINFIG2ACOMBININGEQS1–4WITHEQS5–6,ITFOLLOWSTHATTHEDISTRIBUTIONSOFTHEU,V,T,PATZCOORDINATESSHOULDBESYMMETRICAL,WITHTHEMIRRORAXISBEINGZ0,ANDCONSEQUENTLYTHEU,VAVERAGEDINHALFGAPTHICKNESSISEQUALTOTHATAVERAGEDINWHOLEGAPTHICKNESSBASEDONTHISCHARACTERISTIC,WECANDIVIDETHEWHOLECAVITYINTOTWOEQUALPARTSINTHEGAPWISEDIRECTION,ASDESCRIBEDBYPARTIANDPARTIIINFIG2BATTHESAMETIME,TRIANGULARFINITEELEMENTSAREGENERATEDINTHESURFACESOFTHECAVITYATZ0INFIG2B,INSTEADOFTHEMIDDLEPLANEATZ0INFIG2AACCORDINGLY,FINITEDIFFERENCEINCREMENTSINTHEGAPWISEDIRECTIONAREEMPLOYEDONLYINTHEINSIDEOFTHESURFACESWALLTOMIDDLE/CENTERLINE,WHICH,INFIG2B,MEANSFROMZ0TOZBTHISISSINGLESIDEDINSTEADOFTWOSIDEDWITHRESPECTTOTHEMIDDLEPLANEIEFROMTHEMIDDLELINETOTWOWALLSINADDITION,THECOORDINATESYSTEMISCHANGEDFROMFIG2ATOFIG2BTOALTERTHEFINITEELEMENT/FINITEDIFFERENCESCHEME,ASSHOWNINFIG2BWITHTHEABOVEADJUSTMENT,GOVERNINGEQUATIONSARESTILLEQS1–4HOWEVER,THEORIGINALBOUNDARYCONDITIONSINTHEGAPWISEDIRECTIONAREREWRITTENASUWV0,TTWATZ07?U?Z0?V?Z,?T?Z0,W0ATZB8MEANWHILE,ADDITIONALBOUNDARYCONDITIONSMUSTBEEMPLOYEDATZBINORDERTOKEEPTHEFLOWSATTHEJUNCTUREOFTHETWOPARTSATTHESAMESECTIONCOORDINATE7UIUIIVIVIITITIIPIPIIATZB9CM?ICM?II10WHERESUBSCRIPTSI,IIREPRESENTTHEPARAMETERSOFPARTIANDPARTII,RESPECTIVELY,ANDCMIANDCMIIINDICATETHEMOVINGFREEFIG2A,BILLUSTRATIVEOFBOUNDARYCONDITIONSINTHEGAPWISEDIRECTIONAOFTHEMIDDLEPLANEMODELBOFTHESURFACEMODELMELTFRONTSOFTHESURFACESOFTHEDIVIDEDTWOPARTSINTHEFILLINGSTAGEITSHOULDBENOTEDTHAT,UNLIKECONDITIONSEQS7AND8,ENSURINGCONDITIONSEQS9AND10AREUPHELDINNUMERICALIMPLEMENTATIONSBECOMESMOREDIFFICULTDUETOTHEFOLLOWINGREASONS1THESURFACESATTHESAMESECTIONHAVEBEENMESHEDRESPECTIVELY,WHICHLEADSTOADISTINCTIVEPATTERNOFFINITEELEMENTSATTHESAMESECTIONTHUS,ANINTERPOLATIONOPERATIONSHOULDBEEMPLOYEDFORU,V,T,PDURINGTHECOMPARISONBETWEENTHETWOPARTSATTHEJUNCTURE2BECAUSETHETWOPARTSHAVERESPECTIVEFLOWFIELDSWITHRESPECTTOTHENODESATPOINTAANDPOINTCASSHOWNINFIG2BATTHESAMESECTION,ITISPOSSIBLETOHAVEEITHERBOTHFILLEDORONEFILLEDANDONEEMPTYTHESETWOCASESSHOULDBEHANDLEDSEPARATELY,AVERAGINGTHEOPERATIONFORTHEFORMER,WHEREASASSIGNINGOPERATIONFORTHELATTER3ITFOLLOWSTHATASMALLDIFFERENCEBETWEENTHEMELTFRONTSISPERMISSIBLETHATALLOWANCECANBEIMPLEMENTEDBYTIMEALLOWANCECONTROLORPREFERABLELOCATIONALLOWANCECONTROLOFTHEMELTFRONTNODES4THEBOUNDARIESOFTHEFLOWFIELDEXPANDBYEACHMELTFRONTADVANCEMENT,SOITISNECESSARYTOCHECKTHECONDITIONEQ10AFTEREACHCHANGEINTHEMELTFRONT5INVIEWOFABOVEMENTIONEDANALYSIS,THEPHYSICALPARAMETERSATTHENODESOFTHESAMESECTIONSHOULDBECOMPAREDANDADJUSTED,SOTHEINFORMATIONDESCRIBINGFINITEELEMENTSOFTHESAMESECTIONSHOULDBEPREPAREDBEFORESIMULATION,THATIS,THEMATCHINGOPERATIONAMONGTHEELEMENTSSHOULDBEPREFORMED222NUMERICALIMPLEMENTATIONPRESSUREFIELDINMODELINGVISCOSITYΗ,WHICHISAFUNCTIONOFSHEARRATE,TEMPERATUREANDPRESSUREOFMELT,THESHEARTHINNINGBEHAVIORCANBEWELLREPRESENTEDBYACROSSTYPEMODELSUCHASΗ˙Γ,T,PΗ0T,P1?Η0˙Γ?Τ??1?N11WHERENCORRESPONDSTOTHEPOWERLAWINDEX,ANDΤ?CHARACTERIZESTHESHEARSTRESSLEVELOFTHETRANSITIONREGIONBETWEENTHENEWTONIANANDPOWERLAWASYMPTOTICLIMITSINTERMSOFAN

簡(jiǎn)介：AWATERFLOWMETERUSINGDUALFIBERBRAGGGRATINGSENSORSANDCROSSCORRELATIONTECHNIQUEABSTRACTINTHISPAPER,APRINCIPLEANDEXPERIMENTALRESULTSOFACROSSCORRELATIONFLOWMETERUSINGFIBERBRAGGGRATINGFBGSENSORSAREPRESENTEDTHEFLOWMETERHASNOELECTRONICSANDNOMECHANICALPARTSINITSSENSINGPARTANDTHESTRUCTUREISTHUSSIMPLEANDIMMUNETOELECTROMAGNETICINTERFERENCEEMIFORWATERFLOWMEASUREMENT,THEFLOWMETERUSESTHETIMEDELAYOFTHEVORTEXSIGNALGENERATEDBYABLUFFBODYKARMANVORTEXSHEDDINGFREQUENCYISALSODETECTEDANDUTILIZEDFORTHEFLOWVELOCITYESTIMATIONINTHESYSTEMINORDERTOREALIZEALOWNOISEANDWIDEBANDWIDTHSYSTEM,WEEMPLOYEDINTERFEROMETRICDETECTIONASAFBGWAVELENGTHSHIFTDETECTIONMETHODTHENOISESPECTRALDENSITYOFTHEFBGSENSORWITHTHEINTERFEROMETRICDETECTIONWAS410?4PM/HZ1/2CORRESPONDINGTO033NΕ/HZ1/2AWATERFLOWEXPERIMENTSHOWEDTHATTHEFLOWMETERHADALINEARCHARACTERISTICATVELOCITYRANGEFROM0TO10M/SANDTHEMINIMUMDETECTABLEVELOCITYOF005M/S1INTRODUCTIONFIBERBRAGGGRATINGFBGSENSORSHAVEVARIOUSADVANTAGESSUCHASSMALLSIZE,SIMPLICITYINSENSINGPRINCIPLE,ELECTROMAGNETICINTERFERENCEEMIIMMUNITYANDCAPABILITYOFMULTIPLEXINGBECAUSEOFTHESEADVANTAGES,ANUMBEROFBASICRESEARCHESANDAPPLICATIONSONFBGSENSORSHAVEBEENMADE1–3INTELECOMMUNICATIONSYSTEMS,FBGSAREUSEDASADDDROPMULTIPLEXERSBECAUSEOFTHEIRNARROWBANDWIDTHTYPICALLY01NMTHEFBGAPPLICATIONTOOPTICALTUNABLEFILTERSISALSOUSEFULFORDISCRIMINATIONOFTHESIGNALSINFBGSENSORSYSTEMS4THEAPPLICATIONSTOSMARTSTRUCTURESANDHEALTHMONITORINGAREATTRACTIVEANDHAVEBEENINVESTIGATEDACTIVELY5,6FBGSAREEMBEDDEDINCOMPOSITEMATERIALSANDUSEDASSTRAINANDTEMPERATURESENSORSINTHEAPPLICATIONINTHEFIELDOFCIVILENGINEERING,STRAINMEASUREMENTSFORBRIDGESANDBUILDINGSAREMADEUSINGFBGSENSORARRAYSWITHWAVELENGTHDIVISIONMULTIPLEXINGWDMANDTIMEDIVISIONMULTIPLEXINGAPPLICATIONISLIMITEDTHEREAREFEWREPORTSCONCERNINGTHECROSSCORRELATIONFLOWMETERUSINGOPTICALSENSORS,NOTLIGHTRAYORLASERBEAM,SUITEDFORWATERFLOWMEASUREMENTINTHISPAPER,WEPRESENTAWATERFLOWMETERUSINGDUALFBGSENSORSANDCROSSCORRELATIONTECHNIQUETHEFLOWMETERHASNOELECTRONICSANDNOMECHANICALPARTSINITSSENSINGPART,ANDTHUSTHESTRUCTUREISSIMPLEATFIRST,WEEXPLAINTHEPRINCIPLEANDTHESCHEMATICDIAGRAMOFTHEFLOWMETERNEXT,WEPRESENTTHENOISEESTIMATIONOFTHEFBGSENSORWITHTHEINTERFEROMETRICDETECTIONUSINGAMACH–ZEHNDERINTERFEROMETERCOMPRISEDOFA22ANDA33COUPLERS9FINALLY,WEDESCRIBEEXPERIMENTALPERFORMANCESOFTHEFBGSENSORANDTHEFLOWMETER2ACROSSCORRELATIONFLOWMETERUSINGFBGSENSORSFIG1SHOWSTHEPRINCIPLEOFTHEFLOWMETERTHECROSSCORRELATIONFLOWMETERPRESENTEDHEREUSESFBGSTRAINSENSORSCOMPRISEDOFFBGSANDMETALCANTILEVERSINTHEFLOWMEASUREMENTSECTION,THEFBGSENSORSANDABLUFFBODYAREUSEDTHEBLUFFBODYWHOSESHAPEISARECTANGULARCOLUMNGENERATESSTABLEVORTICESTHETIMEDELAYBETWEENTHEVORTEXSIGNALSDETECTEDBYTHEFBGSENSORSAREESTIMATEDUSINGTHESMOOTHEDCOHERENCETRANSFORMRSCOTΤ15THEFUNCTIONRSCOTΤISEXPRESSEDASFOLLOWS1??????????????????FGFGFGFRYYXXXYRSCOT1TWHEREGXXFANDGYYFARETHEPOWERSPECTRAOFTHEUPSTREAMANDDOWNSTREAMSENSORSIGNALS,GXYFISTHECROSSSPECTRUMOFTWOSIGNALSANDF?1DENOTESTHEINVERSEFOURIERTRANSFORMTHEFUNCTIONRSCOTΤISACROSSCORRELATIONFUNCTIONWEIGHTEDWITHTHECOHERENCEOFTHESIGNALSANDCANDETECTTHETIMEDELAYMOREPRECISELYANDROBUSTLYTHANTHESIMPLECROSSCORRELATIONFUNCTIONTHEMAXIMUMOFRSCOTΤISTHEBESTESTIMATE_TOFTHETIMEDELAYBETWEENTWOFBGSENSORSTHEMEASUREDVELOCITYVMEASISTHENCALCULATEDFROMTHEFOLLOWINGSIMPLEEQUATION2T??SMEASDVWHEREDSISTHEDISTANCEBETWEENTWOSENSORS

簡(jiǎn)介：外文文獻(xiàn)原文ARTIFICIALNEURALNETWORKSINSHORTTERMLOADFORECASTINGKFREINSCHMIDT,PRESIDENTBLINGSTONEHWEBSTERADVANCEDSYSTEMSDEVELOPMENTSERVICES,INC245SUMMERSTREETBOSTON,U02210PHONE6175891841ABSTRACTWEDISCUSSTHEUSEOFARTIFICIALNEURALNETWORKSTOTHESHORTTERMFORECASTINGOFLOADSINTHISSYSTEM,THEREARETWOTYPESOFNEURALNETWORKSNONLINEARANDLINEARNEURALNETWORKSTHENONLINEARNEURALNETWORKISUSEDTOCAPTURETHEHIGHLYNONLINEARRELATIONBETWEENTHELOADANDVARIOUSINPUTPARAMETERSANEURALNETWORKBASEDARMAMODELISMAINLYUSEDTOCAPTURETHELOADVARIATIONOVERAVERYSHORTTIMEPERIODOURSYSTEMCANACHIEVEAGOODACCURACYINSHORTTERMLOADFORECASTINGKEYWORDSSHORTTERMLOADFORECASTING,ARTIFICIALNEURALNETWORK1、INTRODUCTIONSHORTTERMHOURLYLOADFORECASTINGISANESSENTIALHCTIONINELECTRICPOWEROPERATIONSACCURATESHOIRTTERMLOADFORECASTSAREESSENTIALFOREFFICIENTGENERATIONDISPATCH,UNITCOMMITMENT,DEMANDSIDEMANAGEMENT,SHORTTERMMAINTENANCESCHEDULINGANDOTHERPURPOSESIMPROVEMENTSINTHEACCURACYOFSHORTTERMLOADFORECASTSCANRESULTINSIGNIFICANTFINANCIALSAVINGSFORUTILITIESANDCOGENERATORSVARIOUSTECLMIQUESFORPOWERSYSTEMLOADFORECASTINGHAVEBEENREPORTEDINLITERATURETHOSEINCLUDEMULTIPLELINEARREGRESSION,TIMESERIES,GENERALEXPONENTIALSMOOTHING,KALMANFILTERING,EXPERTSYSTEM,ANDARTIFICIALNEURALNETWORKSDUETOTHEHIGHLYNONLINEARRELATIONSBETWEENPOWERLOADANDVARIOUSPARAMETERSWHETHER2、VARIABLESAFFERTINGSHORTTERMLOADSOMEOFTHEVARIABLESAFFECTINGSHORTTERMELECTXICALLOADARETEMPERATUREHUMIDITYWINDSPEEDCLOUDCOVERLENGTHOFDAYLIGHTGEOGRAPHICALREGIONHOLIDAYSECONOMICFACTORSCLEARLY,THEIMPACTSOFTHESEVARIABLESDEPENDONTHETYPEOFLOADVARIATIONSINTEMPERATURE,FOREXAMPLE,HAVEALARGEREFFECTONRESIDENTIALANDCOMMERCIALLOADSTHANONINDUSTRIALLOADREGIONSWITHRELATIVELYHIGHRESIDENTIALLOADSWILLHAVEHIGHERVARIATIONSINSHORTTERMLOADDUETOWEATHERCONDITIONSTHANREGIONSWITHRELATIVELYHIGHINDUSTRIALLOADSINDUSTRIALREGIONS,HOWEVER,WILLHAVEAGREATERVARIATIONDUETOECONOMICFACTORS,SUCHASHOLIDAYSASANEXAMPLE,FIGURE21SHOWSTHELOADVARIATIONOVERONEDAY,STARTINGATMIDNIGHTFIGURE21EXAMPLEOFLOADVARIATIONDURINGONEDAY

簡(jiǎn)介：出處出處ERKAN?,HASTEMOGLUHBUILDINGEVACUATEMODULEFORURBANUNDERGROUNDPASSAGESSUBWAYSTATIONINTURKEYJJOURNALOFTRANSPORTATIONTECHNOLOGIES,2015,5011中文中文3710字為城市地下通道建造安全模塊為城市地下通道建造安全模塊土耳其地鐵車站土耳其地鐵車站ERKAN?,HASTEMOGLUH摘要摘要在地鐵或者地下通道中人群疏散的主要任務(wù)就是當(dāng)緊急情況發(fā)生的時(shí)候在最短的時(shí)間內(nèi)疏散到安全地帶的人越多越好。本文以土耳其為例，選擇了位于伊斯坦布爾的一個(gè)地鐵的地下通道。運(yùn)用了以網(wǎng)站調(diào)查、現(xiàn)場(chǎng)試驗(yàn)和計(jì)算機(jī)模擬相結(jié)的研究方法的新型軟件。它被稱為建筑疏散模塊軟件。我們提出一個(gè)經(jīng)過(guò)深度分析后得出的有關(guān)于通道的數(shù)量和寬度、渠道化設(shè)置和行人的疏散時(shí)間的結(jié)果報(bào)告。并且使用大數(shù)據(jù)觀點(diǎn)是對(duì)公眾的影響效果最好的解釋。此外，行人疏散條件記錄在三個(gè)疏散時(shí)間早上高峰期，平時(shí)和晚上高峰期。通過(guò)峰值觀察和統(tǒng)計(jì)獲得的視頻，并且構(gòu)建模型來(lái)模擬疏散的行人的變化。因此當(dāng)它顯示行人的數(shù)量接近超過(guò)200時(shí)，現(xiàn)場(chǎng)試驗(yàn)和仿真條件基本一致。關(guān)鍵詞關(guān)鍵詞運(yùn)輸計(jì)劃、建造疏散模塊、人群疏散、地鐵車站1、導(dǎo)論、導(dǎo)論如今，對(duì)于土耳其來(lái)說(shuō)地下通道的人群疏散城市突發(fā)事件已經(jīng)成為一個(gè)不可缺少的環(huán)節(jié)，但是對(duì)于這個(gè)主題的研究還是不夠的。然而，關(guān)于這個(gè)方面的研究不是很多，其中相關(guān)的理論基礎(chǔ)還相對(duì)薄弱，甚至是非常困難的。因此，在大規(guī)模人群疏散城市的地下通道有緊急事件發(fā)生時(shí)的研究，以便提高人群疏散的能力已經(jīng)成為一個(gè)關(guān)鍵的主題，可以廣泛的影響城市的安全與社會(huì)的穩(wěn)定。人群管理、控制和疏散在土耳其是非常新的方法，計(jì)算機(jī)仿真技術(shù)通常應(yīng)用于開(kāi)發(fā)海外安全管理工作計(jì)劃。這些模擬可以用來(lái)分析建筑物、地鐵、輕軌、場(chǎng)館和交通網(wǎng)絡(luò)的疏散，在計(jì)劃的過(guò)程中，仿真模型提供了評(píng)估網(wǎng)絡(luò)間隙的時(shí)間或者檢測(cè)應(yīng)急疏散的問(wèn)題。研究表明，當(dāng)研究人員安全通過(guò)街道到達(dá)地下通道時(shí)，研究表明行人的主觀條件壞于客觀條件?？úㄌ氐忍峁┝艘粋€(gè)在公路隧道的應(yīng)急管理決策支持系統(tǒng)的集成的實(shí)時(shí)模型。主要的區(qū)別在于這個(gè)模型可以提供結(jié)果快于真實(shí)時(shí)間（少于5秒）但是其他的模型運(yùn)行的運(yùn)行時(shí)間確實(shí)高。度為12米/秒。圖1模擬的場(chǎng)景為四個(gè)出口門(mén)圖2出口寬度的疏散時(shí)間圖3顯示了疏散通道寬度的增加直接提高疏散效率。當(dāng)出口寬度為3米時(shí)，疏散時(shí)間是798秒，然而，當(dāng)寬度增加到6米時(shí)，疏散時(shí)間是396秒。這意味著當(dāng)疏散通道的寬度增加，疏散的時(shí)間不成比例縮少，但是需要更多的時(shí)間。因此，出口寬度的建筑設(shè)施應(yīng)設(shè)置合理根據(jù)需要的場(chǎng)所。23通道渠化設(shè)置通道渠化設(shè)置疏散出口的疏散速度和行人之間的干擾可以通過(guò)寬度和數(shù)量的影響；此外,通過(guò)合理的渠化設(shè)置也可以增加行人的疏散效率。緊急情況下,疏散門(mén)的寬度是1米,疏散的數(shù)量是100人,速度為12米/秒。我們建立了四種情況，分別為行人自我疏散，一段渠化設(shè)置，雙通道和三通道渠化設(shè)置，渠化設(shè)置如圖4。該圖表明，為了提高效率和安全性，當(dāng)緊急疏散情況疏散行人時(shí)建立有效的渠化導(dǎo)流物體在入口和出口之間可以減少?zèng)_突也可以提高速度和撤離的命令。當(dāng)設(shè)置太多的信道在疏散出口,它會(huì)太繁雜,從而疏散效率會(huì)減少。24行人的數(shù)量行人的數(shù)量行人的數(shù)量也是一個(gè)很重要的因素。在本例中，我們假設(shè)分別有50,100,150,200,250人疏散速度為12米/秒，在長(zhǎng)度為20米，寬度為2米的地下通道里。疏散模擬場(chǎng)景如圖5所示的建筑疏散模塊（BEM）。行人數(shù)和疏散時(shí)間的關(guān)系如圖6所示。圖6顯示了疏散時(shí)間隨著行人的數(shù)量增加而上升。然而，趨勢(shì)圖表明，疏散時(shí)間不隨行人的數(shù)量成比例增加。疏散行人的數(shù)量更多的需求,和更高的通道堵塞,導(dǎo)致行人疏散的效率的下降。特別是當(dāng)行人數(shù)達(dá)到200以上，疏散時(shí)間明顯增加。此外，受損的殘疾人也導(dǎo)致疏散效率LED下降13。因此，有關(guān)管理部門(mén)應(yīng)加強(qiáng)對(duì)通道行人數(shù)量的控制以減少疏散過(guò)程中的意外干擾。25公眾輿論的影響公眾輿論的影響特別是在群體性突發(fā)事件的發(fā)生時(shí)，在地下通道或地鐵指相關(guān)網(wǎng)絡(luò)輿情應(yīng)急監(jiān)測(cè)。因?yàn)楹芏嗑o急情況的變化因素,復(fù)雜的內(nèi)部關(guān)系,預(yù)測(cè)發(fā)展趨勢(shì)和復(fù)雜的相關(guān)信息，美國(guó)政府很難做

簡(jiǎn)介：中文中文4650字出處出處ZUNINP,LEARDIR,BISIOA,ETALOXIDATIVESTABILITYOFVIRGINOLIVEOILENRICHEDWITHCARNOSICACIDJFOODRESEARCHINTERNATIONAL,2010,43515111516畢業(yè)設(shè)計(jì)論文外文資料翻譯題目富含鼠尾草酸的初榨橄欖油的氧化穩(wěn)定性富含鼠尾草酸的初榨橄欖油的氧化穩(wěn)定性院系名稱院系名稱糧油食品學(xué)院糧油食品學(xué)院專業(yè)班級(jí)專業(yè)班級(jí)食工食工F0905F0905學(xué)生姓名學(xué)生姓名學(xué)號(hào)號(hào)指導(dǎo)教師指導(dǎo)教師教師職稱教師職稱起止日期起止日期地點(diǎn)這些過(guò)程。因此，將這些植物次級(jí)代謝產(chǎn)物加入食物中可能極大地促進(jìn)消費(fèi)者的健康利益和提高產(chǎn)品自身的穩(wěn)定性。為了要提高橄欖油的營(yíng)養(yǎng)價(jià)值和就功能性食品構(gòu)想而言，在橄欖油中添加鼠尾草酸會(huì)特別有趣，因?yàn)樗鼤?huì)增加其內(nèi)酚抗氧化劑的自由基清除能力，特別是主要來(lái)源于橄欖葡萄糖甙的維生素E（100400毫克/公斤）和親水性植物酚（40800毫克/公斤）,鼠尾草酸（簡(jiǎn)稱CA）是在各種不同的薄荷科植物例如鼠尾草和迷迭香CHANG,OSTRICMATIJASEVIC,HSIEH,CURVELIER,RICHARD,HUANG,FRANKEL,SCHWARZ,AESCHBACH,GERMAN,1996,油菜籽（TROJAKOVA，REBLOVA，POKORNY，2000和魚(yú)油（FRANKEL，HUANG,PRIOR，AESCHBACH，1996和在仿制的系統(tǒng)中（MIURA，KIKUZAKI，NAKATANI，2002被研究。此外，HOPIA等人（1996報(bào)告指出在玉米油中鼠尾草酸在氧化過(guò)程中對(duì)A生育酚展現(xiàn)了一種極大地保護(hù)作用。這種效果的可能機(jī)制也許類似于抗壞血酸，即鼠尾草酸會(huì)減少生育酚自由基成為活性生育酚。因此，鼠尾草酸可能通過(guò)一個(gè)節(jié)約效應(yīng)在氧化中保護(hù)A生育酚（HOPIA等人，1996。因此，這項(xiàng)研究的目的是為了評(píng)價(jià)不同劑量的鼠尾草酸添加量對(duì)橄欖原油的影響。60℃油的加速老化和油炸食物體溫情況（180℃）二者均被考慮在內(nèi)。通過(guò)第一和第二氧化產(chǎn)物的量評(píng)估油脂氧化趨勢(shì)。使用DPPH測(cè)試加熱油脂的自由基清除能力。2、實(shí)驗(yàn)21材料鼠尾草酸從鼠尾草和迷迭香葉中提取，利用柱層析法提純（MARRERO，ANDRéS，LUIS，2002。特純橄欖油來(lái)自于當(dāng)?shù)厥袌?chǎng)購(gòu)買。對(duì)氨基苯甲醚和1,1二苯基2苦基偕腙肼自由基（DPPH由SIGMACHEMIE公司（STEINHEIM，德

簡(jiǎn)介：中文中文5500字ANANALYTICAPPROACHTOTHEUNSTEADYHEATCONDUCTIONPROCESSESINONEDIMENSIONALCOMPOSITEMEDIA一維符合材料介質(zhì)非穩(wěn)態(tài)傳熱過(guò)程的分析方法一維符合材料介質(zhì)非穩(wěn)態(tài)傳熱過(guò)程的分析方法摘要一維層疊體瞬態(tài)傳熱問(wèn)題常采用基于VODICKA的傳統(tǒng)方法解決，然而，如果把每一層的熱擴(kuò)散系數(shù)放在傳熱方程的一側(cè)，在時(shí)間變量函數(shù)采集點(diǎn)處，采用分離變量法對(duì)傳熱方程進(jìn)行修正，則修正傳熱方程自動(dòng)成立，表示處于一種透明的物理狀態(tài)。這種自動(dòng)的選擇簡(jiǎn)化了對(duì)復(fù)合材料介質(zhì)的非穩(wěn)態(tài)傳熱分析，與傳統(tǒng)方法比較，熱效應(yīng)計(jì)算簡(jiǎn)化成了一種相對(duì)簡(jiǎn)單的數(shù)學(xué)問(wèn)題。1、緒論、緒論一種實(shí)際應(yīng)用于層疊系列復(fù)合材料的瞬態(tài)溫度效應(yīng)的閉式方法最初是由VODICKA提出的，他采用分離變量法解熱傳問(wèn)題的偏微分方程，在變量分離時(shí)，VODICKA將熱擴(kuò)散系數(shù)保留在傳熱方程的一側(cè)，在傳熱方程中建立空間變量函數(shù)。這種選擇使得時(shí)間變量函數(shù)獨(dú)立于熱擴(kuò)散，因此，盡管這種方法可以給出正確的定量的結(jié)果，但并不能表示真實(shí)的物理問(wèn)題，而且特征值和相應(yīng)的本征函數(shù)的計(jì)算非常耗時(shí)且復(fù)雜。在VODICKA之后，復(fù)合材料的非穩(wěn)態(tài)傳熱問(wèn)題的分析經(jīng)過(guò)50多年的發(fā)展，其中包括一些個(gè)人的貢獻(xiàn)，2、M層非穩(wěn)態(tài)傳熱數(shù)學(xué)建模層非穩(wěn)態(tài)傳熱數(shù)學(xué)建模假定一復(fù)合材料有M層平板處于理想化熱接觸條件，如圖1所示，和分別是第I層的熱傳到效率和熱擴(kuò)散效率（I1,2M），初始體（T0），限制其變化范圍X,具有特定的溫度F（X）。T0時(shí)刻，固體復(fù)合材1≤≤1料兩界面受到對(duì)流熱通量的作用，溫度為，傳熱系數(shù)為的流體流經(jīng)X的∞?11外表面，另有一具有相同的溫度，傳熱系數(shù)為的流體流經(jīng)另外一邊的∞?1外表面X。1外部邊界條件（X）?1（??）1?1（1，）0（5）初始邊界條件?（，0）（）∈，1（1,2，，）（6）公式（3）表明，相互獨(dú)立的M層板材料表面兩相鄰區(qū)域的溫度相等，公式（4）則相反，熱通量連續(xù)，與內(nèi)界面相對(duì)應(yīng)，公式（1）（6）可通過(guò)分析求解。33自然分析法解自然分析法解M層非穩(wěn)態(tài)傳熱問(wèn)題層非穩(wěn)態(tài)傳熱問(wèn)題公式（1）可通過(guò)工件假設(shè)法求解（分離變量法）定義為（，）（）（）≥0,∈，1（1,2，，）（7）由公式（7）替代（1），得到傳熱修正方程11（）1?2≥0，∈，1（1,2，，），（8）是分離常量，與各層相對(duì)應(yīng)，且與物理約束條件相關(guān)聯(lián)，（1,2，）分離變量時(shí)，熱擴(kuò)散率保留在公式（8）的左邊，建立隨時(shí)間變化的函數(shù)，自然分析法使得函數(shù)明顯依賴于相應(yīng)的熱擴(kuò)散率，所以，問(wèn)題的解析結(jié)果（）與瞬態(tài)熱傳導(dǎo)過(guò)程的物理事實(shí)保持一致。公式（8）給出的自然分離產(chǎn)生從2到M的通用型微分方程。20，≥0（1,2，），（9）1（）20,∈，1（1,2，，）（10）可過(guò)公式（9）解時(shí)間變量函數(shù)，得（）?2，≥0（1,2，）（

簡(jiǎn)介：英文文獻(xiàn)英文文獻(xiàn)ANINTRODUCTORYGUIDETOBUILDINGANDDEPLOYINGMORESECURESITESWITHASPNETANDIISSUMMARYASPNETANDMICROSOFTINTERNETINFORMATIONSERVICESIISWORKTOGETHERTOMAKEBUILDINGSECUREWEBSITESABREEZEBUTTODOITRIGHT,YOUHAVETOKNOWHOWTHETWOINTERRELATEANDWHATOPTIONSTHEYPROVIDEFORSECURINGACCESSTOAWEBSITESRESOURCESTHISARTICLE,THEFIRSTINATWOPARTSERIES,EXPLAINSTHEABCSOFWEBSECURITYASSEENTHROUGHTHEEYESOFASPNETANDINCLUDESAHANDSONTUTORIALDEMONSTRATINGWINDOWSAUTHENTICATIONANDACLAUTHORIZATIONSARANGEOFSECURITYMEASURESANDAUTHENTICATIONMETHODSAREDISCUSSED,INCLUDINGBASICAUTHENTICATION,DIGESTAUTHENTICATION,ANDROLEBASEDSECURITYTHERESANOLDADAGEAMONGDEVELOPERSTHATSAYSBUILDINGSECURITYINTOSOFTWAREISLIKEPAYINGTAXESYOUKNOWITSIMPORTANTANDYOUKNOWYOUMUSTDOITSOONERORLATER,BUTYOUPUTITOFFASLONGASYOUCANANDWHENYOUFINALLYDOIT,YOUDOSOONLYBECAUSEYOUHAVETOYOUMIGHTNOTGOTOJAILFORBUILDINGINSECUREAPPLICATIONS,BUTSECURITYISNOLESSIMPORTANTBECAUSEOFITINMANYAPPLICATIONSWEBAPPLICATIONSINPARTICULARSECURITYISNTALUXURYITSANECESSITYSECURITYISABIGDEALINNETWORKAPPLICATIONSBECAUSEBYNATURETHOSEAPPLICATIONSAREAVAILABLETOANDVULNERABLETOMISUSEBYANDATTACKSFROMALARGERPOPULATIONOFUSERSWHENTHENETWORKTOWHICHANAPPLICATIONISDEPLOYEDISTHEINTERNET,SECURITYBECOMESEVENMOREIMPORTANTBECAUSETHELISTOFPOTENTIALUSERSGROWSTOABOUTFOURBILLIONWEBSECURITYISABROADANDCOMPLICATEDSUBJECTMUCHOFTHEONGOINGRESEARCHINTHEFIELDHASTODOWITHHARDENINGWEBSERVERSAGAINSTATTACKSMICROSOFT?INTERNETINFORMATIONSERVICESIISADMINISTRATORSAREALLTOOAWAREOFTHEPASTSECURITYHOLESINIISANDOFSEVERALPATCHESANDSECURITYUPDATESFROMREDMONDBUTTHISARTICLEISNTABOUTPROTECTINGSERVERSFROMBUFFEROVERRUNSANDOTHERHACKATTACKSRATHER,THISARTICLEISABOUTUSINGASPNETTOBUILDSECURESITESTHATSERVEUPPAGESONLYTOAUTHORIZEDUSERSATASLIGHTLYDEEPERLEVEL,YOUMIGHTWANTTOKNOWWHOREQUESTEDTHEPAGESOYOUCANPERSONALIZEITFORTHATINDIVIDUALEITHERFORMOFPROTECTIONREQUIRESTWOOVERTACTIONSONTHEPARTOFTHEAPPLICATIONIDENTIFYTHEORIGINATOROFEACHREQUESTANDDEFINERULESTHATGOVERNWHOCANACCESSWHICHPAGESAWEBSERVERIDENTIFIESCALLERSUSINGAMECHANISMCALLEDAUTHENTICATIONONCEACALLERISIDENTIFIED,AUTHORIZATIONDETERMINESWHICHPAGESTHATPARTICULARCALLERISALLOWEDTOVIEWASPNETSUPPORTSAVARIETYOFAUTHENTICATIONANDAUTHORIZATIONMODELSUNDERSTANDINGTHEOPTIONSTHATAREAVAILABLETOYOUANDHOWTHEYINTERRELATEISANIMPORTANTFIRSTSTEPINDESIGNINGASITETHATRESTRICTSACCESSTOSOMEORALLOFITSRESOURCESORTHATPERSONALIZESCONTENTFORINDIVIDUALUSERSAUTHENTICATIONAUTHENTICATIONENABLESTHERECIPIENTOFAREQUESTTOASCERTAINTHECALLERSIDENTITYTHECALLERMIGHTCLAIMTOBEBOB,BUTYOUDONTKNOWHEREALLYISBOBUNLESSYOUAUTHENTICATEHIMASPNETSUPPORTSTHREETYPESOFAUTHENTICATIONWINDOWSAUTHENTICATION,PASSPORTAUTHENTICATION,ANDFORMSAUTHENTICATIONWHENWINDOWSAUTHENTICATIONISSELECTED,ASPNETLOOKSTOIISFORHELPIISDOESTHEHARDPARTBYAUTHENTICATINGTHECALLERTHENITMAKESTHECALLERSIDENTITYAVAILABLETOASPNETLETSSAYWINDOWSAUTHENTICATIONISENABLEDANDBOBREQUESTSANASPXFILEIISAUTHENTICATESBOBANDFORWARDSTHEREQUESTTOASPNETALONGWITHANACCESSTOKENIDENTIFYINGBOBASPNETUSESTHETOKENTOMAKESUREBOBHASPERMISSIONTORETRIEVETHEPAGEHEREQUESTEDASPNETALSOMAKESTHETOKENAVAILABLETOTHEAPPLICATIONTHATHANDLESTHEREQUESTSOTHATATITSDISCRETION,THEAPPLICATIONCANIMPERSONATEBOBTHATIS,TEMPORARILYASSUMEBOBSIDENTITYTOPREVENTCODEEXECUTEDWITHINTHEREQUESTFROMACCESSINGRESOURCESTHATBOBLACKSPERMISSIONTOACCESSFORWEBAPPLICATIONS,WINDOWSAUTHENTICATIONISTYPICALLYUSEDINTHEFOLLOWINGSCENARIOSYOURAPPLICATIONISDEPLOYEDONTHECOMPANYSINTRANETANDEVERYONEWHOUSESITHASANACCOUNTTHATTHEYCANUSETOLOGINANDACCESSNETWORKRESOURCES

簡(jiǎn)介：機(jī)械工程學(xué)院畢業(yè)設(shè)計(jì)（論文）外文資料翻譯教科部專業(yè)姓名學(xué)號(hào)外文出處FREESCALESEMICONDUCTOR（用外文寫(xiě)）CODEWARRIORDEVELOPMENTSTUDIO附件INTRODUCTIONTOCODEWARRIORDEVELOPMENTTOOLS指導(dǎo)老師評(píng)語(yǔ)簽名系統(tǒng)功能的一個(gè)簡(jiǎn)單界面，比如可以在控制面板中完成諸如設(shè)置音量和鼠標(biāo)移動(dòng)速度這樣一些參數(shù)。動(dòng)態(tài)鏈接庫(kù)DLLS提供了一些很有用的被系統(tǒng)和應(yīng)用程序共享的函數(shù)。通常它們都是沒(méi)有用戶界面的。插件PLUGINS有點(diǎn)類似于DLLS，插件也是可供其它軟件使用的小程序，但插件只能被特定的軟件使用。比如說(shuō)，PHOTOSHOP的插件允許程序員方便地?cái)U(kuò)展PHOTOSHOP的功能，而不需要去修改它的源代碼。同樣的，許多WEB瀏覽器也使用插件來(lái)增加功能，或者為了讓你能夠看到頁(yè)面上的新的內(nèi)容類型。實(shí)際上，有許多程序，包括CODEWARRIOR，都使用這種插件結(jié)構(gòu)。一旦你掌握了CODEWARIOR和你所使用的操作系統(tǒng)的編程接口時(shí)，你可以編寫(xiě)許多其它類型的程序。實(shí)際上，本課程也是你深入學(xué)習(xí)其它編程方法的基礎(chǔ)課程。你已經(jīng)找到了一個(gè)最優(yōu)秀的地方開(kāi)始你的編程之旅。二、什么是工程文件二、什么是工程文件為了使用CODEWARRIOR來(lái)創(chuàng)建一個(gè)應(yīng)用程序，你必須創(chuàng)建許多文件來(lái)構(gòu)成一個(gè)工程PROJECT。該工程的設(shè)置和所有這些文件的指針都被存放在一個(gè)工程文件中。這些設(shè)置包括編譯和鏈接設(shè)置、源文件、庫(kù)文件以及它們之間用于產(chǎn)生最終程序的相互關(guān)系。你可以將這個(gè)工程文件看作該工程的大腦它保存了所有文件相互依存的關(guān)系并知道如何將它們組合成為一個(gè)可用的應(yīng)用程序。工程窗口依次顯示了這些關(guān)于你的程序和該程序所包含的文件的信息，并允許你只需輕松點(diǎn)擊就可以修改這個(gè)工程。大多數(shù)組成你的程序的文件都是原始的文本文件。這些文件包含了你在CODEWARRIOR的編輯器中鍵入的源代碼。在某些情況下，你還將使用一些預(yù)編譯的源碼和頭文件。在進(jìn)行數(shù)學(xué)運(yùn)算和I/O操作時(shí)，你還要使用到一些庫(kù)文件，比如METROWERKS標(biāo)準(zhǔn)庫(kù)METROWERKSSTANDARDLIBRARY，MSL通常，你都是使用C或C來(lái)編寫(xiě)源代碼，但通過(guò)給CODEWWARRIOR的集成開(kāi)發(fā)環(huán)境加裝相應(yīng)的插件PLUGIN，你也可以在CODEWARRIOR中使用其它

簡(jiǎn)介：THEEFFECTSOFAIRCONTENTONPERMEABILITYOFLIGHTWEIGHTCONCRETETOMMYYLO?,HZCUI1,ABIDNADEEM1,ZGLI1DEPARTMENTOFBUILDINGANDCONSTRUCTION,CITYUNIVERSITYOFHONGKONG,HONGKONGRECEIVED31JULY2003ACCEPTED23JUNE2006ABSTRACTAIRENTRAININGAGENTISUSEDTOCONTROLTHEFLOATATIONOFLIGHTWEIGHTAGGREGATELWAINLIGHTWEIGHTAGGREGATECONCRETELWAC,THEREFOREREDUCINGTHESEGREGATIONOFLWACATTHESAMETIME,USINGANAIRENTRAININGAGENTWILLAFFECTTHEWATERSORPTIONOFTHECONCRETEINTHISPAPER,TWOLIGHTWEIGHTCONCRETEMIXESOFDENSITY1000KG/M3ANDAIRCONTENTOF135AND319WERECOMPAREDANDTHEEFFECTSOFENTRAINEDAIRONTHESTRENGTH,SURFACESORPTIVITY,ANDCHLORIDEPERMEABILITYOFLWACAREPRESENTEDRESULTSSHOWTHATTHEUSEOFPOROUSLWAWOULDNOTLOWERTHEPERMEABILITYRESISTANCEOFCONCRETEENTRAINEDAIRHADLITTLEEFFECTONSORPTIVITYBUTAMAJOREFFECTONCHLORIDEPERMEABILITYTHEWEAKERPORESNETWORKINTHECEMENTPASTEISTHEBASICCAUSEFORTHEHIGHCHLORIDEPERMEABILITYOFCONCRETETHANTHEUSEOFPOROUSLWAALTHOUGHCHLORIDEPERMEABILITYOFLOWDENSITYLWACCONCRETEDECREASEDWITHAGEOFCONCRETE,ITWASFOUNDTHATTHECONCRETEWASNOTDENSEENOUGHTOSTOPTHECHLORIDEIONTOPENETRATETHROUGHTHECONCRETEBEFORETHECONCRETEMATUREAT90DAYS?2006ELSEVIERLTDALLRIGHTSRESERVEDKEYWORDSLIGHTWEIGHTCONCRETELIGHTWEIGHTEXPANDEDCLAYAGGREGATESORPTIVITYCHLORIDEPERMEABILITYAIRCONTENTCOMPRESSIVESTRENGTH1INTRODUCTIONLOWSTRENGTHLIGHTWEIGHTCONCRETEISUSEDFORPREFABRICATIONOFDRYPARTITIONWALLS,WASHINGROOMANDKITCHENMODULES1–3FORLIGHTWEIGHTAGGREGATECONCRETELWAC,AIRENTRAININGAGENTISUSEDTOCONTROLTHEFLOATATIONOFLIGHTWEIGHTAGGREGATELWATHEREFOREREDUCINGTHESEGREGATIONOFLWACANDLOWERINGTHEDENSITYOFTHERESULTINGCONCRETEHOWEVER,THEWATERSORPTIONOFTHECONCRETEWILLBEINCREASEDATTHESAMETIMEPASTFINDINGS4–7INDICATEDTHATSORPTIVITYCANBECORRELATEDTOPERMEABILITY,ANDISAFUNCTIONOFPOROSITY,POREDIAMETER,DISTRIBUTIONANDCONTINUITYOFPORESWITHINTHECONCRETEMATRIXINMANYCASES,THECHLORIDEPERMEABILITYOFORDINARYCONCRETEUSINGAASHTOMETHOD8ISUSEDTOCOMPARETHEPERMEABILITYOFCONCRETEBUTFEWRESEARCHERSHAVESTUDIEDTHECHLORIDEPERMEABILITYOFLWACINTHISSTUDY,THEEFFECTSOFTHEENTRAINEDAIRONTHESTRENGTH,SORPTIVITYANDPERMEABILITYOFCONCRETEOFTWOLWACMIXESOFDENSITY1000KG/M3WILLBESTUDIEDRESULTSOFTHESURFACESORPTIVITYANDCHLORIDEPERMEABILITYOFCONCRETEWEREANALYZED2MATERIALSANDEXPERIMENTALDETAILS21MATERIALSANDSPECIMENSPREPARATIONTHEBINDERSUSEDWEREPORTLANDCEMENTOPCTOBS1219899,WITHBLAINESURFACEAREAOF330M2/KGANDADENSITYOF3150KG/M3THELWAWASALIGHTWEIGHTEXPANDEDCLAYAGGREGATEFINEAND10MMCOARSEAGGREGATESWEREOFBULKDENSITIESOF955KG/M3AND4038KG/M3,RESPECTIVELYTHELWAWASPREWETTEDWITHHALFOFTHETOTALGAUGINGWATERFOR30MINSOTHATTHEAGGREGATEWAS‘SURFACESATURATED’PRIORTOMIXINGWATERABSORPTIONOF30MINOFTHEFINEANDCOARSEAGGREGATEIS145AND54,RESPECTIVELYTHEMIXPROPORTIONSARESUMMARIZEDINTABLE1TWOCONCRETEMIXESOFTHESAMEW/CRATIOBUTDIFFERENTAIRCONTENTSWEREPREPAREDLIQUIDAIRENTRAININGAGENTINACCORDANCEWITHBS488710WASADDEDTOTHECONCRETEMIXTOCONTROLTHEFLOATATIONOFLWAINTHECEMENTPASTETHERESULTINGFRESHCONCRETEHADGOODWORKABILITYANDTHEFLOATATIONOFLIGHTWEIGHTAGGREGATEANDSEGREGATIONOFCONCRETEWEREWELLCONTROLLEDFOREACHCONCRETEMIX,FOUR100100100MM3CUBESWEREPREPAREDFORTESTATEACHAGETHREEOFTHEMWEREFORCOMPRESSIVETESTANDTHELASTONEWASFORSORPTIONTESTINADDITION,ONEDISCCEMENTANDCONCRETERESEARCH3620061874–1878?CORRESPONDINGAUTHORTEL85227887685FAX85227887612EMAILADDRESSTOMMYCITYUEDUHKTYLO1TEL85227887685FAX8522788761200088846/SEEFRONTMATTER?2006ELSEVIERLTDALLRIGHTSRESERVEDDOI101016/JCEMCONRES200606009MIN05ATAW/CRATIOOF06SOMEOTHERRESEARCHSTUDIESSUGGESTEDTHATOPCCONCRETEWITHW/CRATIOOF04–05WOULDHAVESORPTIVITYOFABOUT023MM/MIN0519–22THEREFORE,THESORPTIVITYVALUEFORTHESELWACWITHLOWSTRENGTHANDAIRCONTENTATW/CRATIOOF040WASNOTPARTICULARLYHIGHWHENCOMPAREDTONORMALWEIGHTCONCRETEOFTHESAMEW/CRATIOASSORPTIONISMAINLYTHROUGHCAPILLARYPORES,THESIMILARITYOFWATERSORPTIVITYOFTHEMIXESWITHDIFFERENTAIRCONTENTSUGGESTEDTHATTHEPORESWITHINTHETWOCONCRETEMIXESWERELARGERTHANCAPILLARYPORESHOWEVER,THECHANGEOFWATERSORPTIVITYWITHAGEISDIFFERENTFROMTHATOFNORMALWEIGHTCONCRETEFORNORMALCONCRETE,WATERSORPTIVITYGENERALLYDECREASEWITHTHEINCREASEINAGEINTHISRESEARCH,SORPTIVITYOFLWACINCREASEWITHAGEFORMIXA,THESORPTIVITYAT7DAYSWAS0122MM/MIN05ANDITINCREASESTO0130MM/MIN05FOR90DAYSTHESIMILARPHENOMENONALSOOCCURSINMIXBTHEMAINREASONFORTHISPHENOMENONWASTHEAPPLICATIONOFTHEAIRENTRAININGAGENTANDTHEUSEOFLIGHTWEIGHTAGGREGATETHEINITIALSORPTIONAASPERTABLE2INCREASESWITHAGEOFCONCRETEINDICATEDTHEMEANOFTHEINITIALSORPTIONFORMIXESAANDBOFTHELWACCHANGESFROM0444MM,066MMTO2465MMAT7DAYS,28DAYSAND90DAYS,RESPECTIVELYITISCLEARTHATCONCRETESORPTIONISCLOSELYRELATEDTOTHESURFACEPORESOFTHECONCRETEPASTETHESURFACEPOREREDUCESASC–S–HANDLWACSTRENGTHALSODEVELOPWITHTIMEACCORDINGLY,ITREDUCESTHEPERMEABILITYANDWATERSORPTIVITYOFCONCRETETHEABOVEPHENOMENONCANBEATTRIBUTEDTOTHEFACTTHATTHEQUANTITYOFPORESOFMIXBISGREATERTHANTHATOFMIXADUETOTHEHIGHERAIRCONTENTTHESURFACESORPTIONOFMIXBISHIGHERATTHEEARLYAGESBUTBECOMESSIMILARAT90DAYSSINCETHECEMENTCONTENTSOFBOTHMIXESAANDBARETHESAME,THECEMENTHYDRATIONANDTHESTRUCTUREOFCAPILLARYPOREWILLBESIMILARTHISEXPLAINSWHYINFIG4THESURFACESORPTIONSOFTHETWOMIXESATTHEAGEOF90DAYSARESIMILARMOREOVER,I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簡(jiǎn)介：EFFECTOFNANOSILICAONTHECOCONTINUOUSMORPHOLOGYOFPOLYPROPYLENE/POLYOLEFINELASTOMERBLENDSSHLEEA,MKONTOPOULOUA,,CBPARKBADEPARTMENTOFCHEMICALENGINEERING,QUEEN’SUNIVERSITY,KINGSTON,ONK7L3N6,CANADABDEPARTMENTOFMECHANICALANDINDUSTRIALENGINEERING,UNIVERSITYOFTORONTO,TORONTO,ONM5S3G8,CANADAARTICLEINFOARTICLEHISTORYRECEIVED25OCTOBER2009RECEIVEDINREVISEDFORM8JANUARY2010ACCEPTED11JANUARY2010AVAILABLEONLINE18JANUARY2010KEYWORDSNANOCOMPOSITESTHERMOPLASTICOLEFINBLENDSCOCONTINUOUSMORPHOLOGYABSTRACTTHISPAPERREPORTSTHEEFFECTOFNANOSILICASIO2ONTHEMORPHOLOGYOFCOCONTINUOUSIMMISCIBLEPOLYPROPYLENEPP/POLYOLEFINELASTOMERPOEBLENDSTHEUNFILLEDBLENDSDISPLAYPHASEINVERSIONANDACOCONTINUOUSSTRUCTUREATARATIOOF50/50PP/POEBYWEIGHTUPONADDITIONOFSIO2INTHEPRESENCEOFMALEATEDPPCOMPATIBILIZERAFINERSTRUCTURE,CONSISTINGOFELONGATEDPOEPARTICLESDISPERSEDWITHINTHEPPPHASEISOBTAINEDTHISTRANSFORMATIONISASSOCIATEDTOTHEPRESENCEOFFINELYDISPERSEDSIO2PARTICLESTHATARELOCALIZEDEXCLUSIVELYWITHINTHEPPMATRIXTHEIMPACTPROPERTIES,FLEXURALANDYOUNG’SMODULIOFTHEBLENDSINCREASESIGNIFICANTLY,POINTINGTOASYNERGISTICEFFECTARISINGFROMTHEPRESENCEOFTHEREINFORCEDPPPHASE,CONTAININGHIGHAMOUNTSOFTHEFINELYDISPERSEDELASTOMERICPHASE?2010ELSEVIERLTDALLRIGHTSRESERVED1INTRODUCTIONPOLYMERBLENDINGISUSEDEXTENSIVELYTODEVELOPNEWMATERIALSTHATEXHIBITAFAVORABLECOMBINATIONOFPROPERTIES,DEPENDINGONTHESELECTIONOFBLENDCOMPONENTSASMOSTPOLYMERSAREIMMISCIBLE,THEIRBLENDSFORMMULTIPHASESYSTEMSWITHVARIOUSMORPHOLOGIESANDSYNERGISTICPROPERTIESTHENATUREOFTHESTRUCTURESCREATEDDURINGPROCESSINGDEPENDSUPONSEVERALFACTORS,SUCHASTHEMATERIALPROPERTIESOFTHENEATPOLYMERSINTERFACIALTENSION,RHEOLOGICALPROPERTIES,PROCESSINGCONDITIONSSHEARRATEANDMIXINGTIMEANDTHERELATIVEAMOUNTSOFMATERIALUSEDTHETYPEOFMORPHOLOGYDETERMINESTOALARGEEXTENTTHEPHYSICALPROPERTIESOFTHEBLENDS,THUSPROPERCONTROLOFTHEMORPHOLOGYPLAYSAKEYROLEININDUCINGDESIRABLEPROPERTIESTOTHEBLENDSTHEDROPLET/MATRIXMORPHOLOGY,WHICHIMPARTSFAVORABLEIMPACTANDOTHERMECHANICALPROPERTIES,ASINTHECASEOFHIGHIMPACTPOLYSTYRENEANDPOLYPROPYLENE,HASBEENWIDELYSTUDIEDCOCONTINUOUSMORPHOLOGIESHAVEALSODRAWNSIGNIFICANTINTEREST1,BECAUSETHEYHAVETHEPOTENTIALTOWIDENTHEAPPLICATIONRANGEFORPOLYMERBLENDSDUETOTHEIRINTERCONNECTEDNATURE1–4COCONTINUOUSMORPHOLOGIESEXHIBITINTERESTINGPROPERTIESRELEVANTTOCONDUCTIVITYORPERMEABILITYOWINGTOTHEPERCOLATIONOFTHETWOPHASESAWIDERANGEOFTECHNIQUESTODETERMINETHECOCONTINUITYREGIONANDTHERESULTINGSTRUCTURES,INCLUDINGSOLVENTEXTRACTION5–9,MICROSCOPY10–14ANDRHEOLOGY10,15–17HAVEBEENDESCRIBEDINTHELITERATUREEXTENSIVERESEARCHDURINGTHELASTDECADEHASCONFIRMEDTHEINFLUENCEOFNANOPARTICLEADDITIONONTHEMORPHOLOGYOFPOLYMERBLENDSITISNOWWIDELYACCEPTEDTHATINTHEPRESENCEOFNANOPARTICLES,SUCHASORGANOCLAYSANDNANOSILICA,THEDROPLETMATRIXMORPHOLOGYSHIFTSTOWARDAFINERDISPERSIONOFTHEMINORPHASETHESELECTIVELOCALIZATIONOFTHENANOFILLERINONEOFTHEPHASES,TYPICALLYTHEMATRIXORTHEINTERPHASE,SEEMSTOBEKEYTOEXPLAININGTHISPHENOMENONPOSSIBLEEXPLANATIONSTHATHAVEBEENOFFEREDINCLUDECOMPATIBILIZINGEFFECTSDUETOFILLERADSORPTIONATTHEINTERFACEOFTHETWOPOLYMERS,RESULTINGINAREDUCTIONINTHEINTERFACIALTENSION18–20HOWEVERTHESEMECHANISMSAREOBVIOUSLYNOTDOMINANTWHENTHEFILLERRESIDESINTHEMATRIX21INTHATCASEITHASBEENSPECULATEDTHATEXFOLIATEDCLAYPLATELETSORWELLDISPERSEDNANOPARTICLESSURROUNDEDBYANIMMOBILIZEDBOUNDLAYEROFPOLYMERMAYHINDERPARTICLECOALESCENCEBYACTINGASPHYSICALBARRIERS22–24ONTHEOTHERHAND,THEREAREQUITEAFEWREPORTSOFNANOFILLERSFAVORINGTHEFORMATIONOFCOCONTINUOUSSTRUCTURESINVARIOUSBLENDCOMBINATIONS25–30INSOMECASES,THEFORMATIONOFADOUBLEPERCOLATEDSTRUCTURE,WHERECONDUCTIVEFILLERSSUCHASCARBONNANOTUBESAREDISPERSEDINONEOFTHECOCONTINUOUSPHASESISDESIRABLEANDISDONEONPURPOSE,SINCEITCANRESULTINFAVORABLECONDUCTIVEPROPERTIES31,32ITISTHEREFORECLEARTHAT,APARTFROMTHEOBVIOUSEFFECTTHATNANOFILLERSHAVEONTHEPHYSICALPROPERTIESOFTHEBLENDS,THEYCANALSOGENERATEAMOREINDIRECTEFFECT,THROUGHTHECONTROLOFTHEIRMORPHOLOGYCORRESPONDINGAUTHORTELT16135333079FAXT16135336637EMAILADDRESSMARIANNAKONTOPOULOUCHEEQUEENSUCAMKONTOPOULOUCONTENTSLISTSAVAILABLEATSCIENCEDIRECTPOLYMERJOURNALHOMEPAGEWWWELSEVIERCOM/LOCATE/POLYMER00323861/–SEEFRONTMATTER?2010ELSEVIERLTDALLRIGHTSRESERVEDDOI101016/JPOLYMER201001018POLYMER5120101147–1155FOURBLOCKSOFKNEADINGDISCSHAVINGPOSITIVET30?,NEUTRAL90?,ANDNEGATIVE?30?STAGGEREDANGLESANDTWOLEFTHANDEDSCREWELEMENTS,TOPROVIDEGOODDISPERSIVEANDDISTRIBUTIVEMIXINGTHESCREWSPEEDWAS200RPM,RESULTINGINANEXTRUSIONRATEOF25KG/HTHETEMPERATUREPROFILEINTHEEXTRUDERFROMTHEFEEDINGSECTIONTOTHEDIEWAS60?C–200?C–205?C–205?C–210?C–210?C–200?CFORALLBLENDSTHESECONDITIONSWERESELECTEDBECAUSEPRIORWORKHASSHOWNTHATTHEYPROVIDETHEOPTIMUMDISPERSIONOFNANOSILICASILICAWASADDEDTOTHE50/50PP/POEBLENDSATLOADINGSRANGINGFROM1TO5WTPPGMANWASUSEDTOIMPROVETHEDISPERSIONOFSIO2RESULTINGINAPPMATRIXCOMPOSITIONOFPP/PPGMAN90/10ANTIOXIDANT03PHRWASADDEDTOALLFORMULATIONS23MECHANICALPROPERTIESTENSILEPROPERTIESWEREMEASUREDUSINGANINSTRON3369UNIVERSALTESTER,ATCROSSHEADSPEEDSOF50MM/MINDUMBBELLSHAPEDSPECIMENSWERECUTWITHATYPEVDIEACCORDINGTOASTMD638FROM15MMTHICKSHEETS,WHICHWEREPREPAREDBYCOMPRESSIONMOLDINGOFTHECOMPOUNDEDSAMPLE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簡(jiǎn)介：AUTOMATICIDENTIFICATIONOFGEOMETRICCONSTRAINTSINMECHANICALASSEMBLIESSHMULLINS?ANDDCANDERSON?MECHANICALASSEMBLIESOFMANUFACTUREDCOMPONENTSINVOLVESETSOFRELATIONSBETWEENMATINGSURFACESANDFUNCTIONALCHARACTERISTICSCOMPONENTSMUSTFITTOGETHERTOASSEMBLEANDFUNCTIONPROPERLY,PLACINGCONSTRAINTSONTHEALLOWABLEVALUESOFTHECOMPONENTDIMENSIONSKINEMATICMOTIONOFTHECOMPONENTSISOFTENNECESSARY,RESULTINGINOTHERGEOMETRICCONSTRAINTSIDENTIFICATIONOFCONSTRAINTSINMODELSOFMECHANICALASSEMBLIESISNECESSARYFORSIMULATIONSOFTHEEFFECTSOFDIMENSIONANDTOLERANCECHANGESTHISPAPERPRESENTSTECHNIQUESFORTHEAUTOMATICIDENTIFICATIONOFSUCHCONSTRAINTSINCOMPUTERMODELSOFTHREEDIMENSIONALASSEMBLIESWITHNONORTHOGONALCONTACTSBETWEENCOMPONENTSURFACESANDKINEMATICJOINTSTHEAPPROACHRELIESONAGRAPHBASEDREPRESENTATIONOFTHEASSEMBLYSEARCHALGORITHMSFORIDENTIFYINGASSEMBLYCONSTRAINTSINTHISGRAPHAREPRESENTED?1998ELSEVIERSCIENCELTDALLRIGHTSRESERVEDKEYWORDSASSEMBLYMODELING,MECHANICALASSEMBLIES,CONSTRAINTSINTRODUCTIONTHEIDENTIFICATIONANDSOLUTIONOFCONSTRAINTRELATIONSHIPSBETWEENCOMPONENTDIMENSIONSINMECHANICALASSEMBLIESISASIGNIFICANTPROBLEMINCOMPUTERAIDEDDESIGNPHYSICALCONTACTSBETWEENCOMPONENTSCREATECONSTRAINTSONTHERELATIVEPOSITIONOFTHECOMPONENTS,THEIRNOMINALDIMENSIONS,ANDTHETOLERANCESONTHOSEDIMENSIONSTHENUMBEROFSUCHCONSTRAINTSCANBELARGEEVENFORRELATIVELYSIMPLEASSEMBLIESSPECIALIZEDTECHNIQUESARENEEDEDTOACCOUNTFORSUCHGEOMETRICCONSTRAINTSTHECONSTRAINTSIDENTIFIEDCANBEUSEDTO1PROVIDEDIMENSIONSENSITIVITYFEEDBACKTOTHEDESIGNER2IDENTIFYRELATIONSHIPSTHATTHEDESIGNERMAYNOTRECOGNIZEORFULLYCOMPREHEND3ALLOWFORREDUCTIONOFDESIGNTIMEBYMAKINGITEASIERTOMODIFYTHEEXISTINGDESIGNAND4BEUSEFULFORBOTHTOPDOWNANDBOTTOMUPDESIGNMODESTOPDOWNASSEMBLYDESIGNSYSTEMSCREATEFUNCTIONALCONSTRAINTSWHICHTHEGEOMETRYMUSTSATISFYBOTTOMUPASSEMBLYDESIGNUSESTHEGEOMETRYTODEFINECONSTRAINTSONTHEDESIGN’SBEHAVIORBOTHAPPROACHESRESULTINCONSTRAINTSTHATARISEFROMCONTACTSANDCONNECTIONSBETWEENTHECOMPONENTSOFTHEASSEMBLY,ANDINEITHERAPPROACHITISNECESSARYTOMAINTAINTHECONSISTENCYOFTHEASSEMBLYTHROUGHOUTDESIGNCHANGESCOMPUTERSUPPORTFORINTEGRATEDDESIGNOFPARTSANDASSEMBLIESREQUIRESCONSTRAINTIDENTIFICATIONANDMANAGEMENTTHEREARETWOCATEGORIESOFGEOMETRICASSEMBLYRELATIONSHIPSMATINGCONDITIONSANDKINEMATICJOINTSINGENERALTERMS,AMATINGCONDITIONISAGEOMETRICRELATIONSHIPBETWEENTWOORMORECOMPONENTSTHATHASSIGNIFICANCEINTHEDESIGNORFABRICATIONPROCESSESMATINGCONDITIONSINCLUDERELATIONSHIPSWHICHINVOLVECONTACTBETWEENPARTS,ASWELLASRELATIONSHIPSINWHICHTWOPARTSDONOTHAVECONTACT,SUCHASCLEARANCECONDITIONSTHEDISTINCTIONBETWEENMATINGCONDITIONSANDKINEMATICJOINTSISTHATTHEGEOMETRICRELATIONSHIPOFAMATINGCONDITIONISSTATICAMATINGCONDITIONDEFINESARELATIONSHIPBETWEENCOMPONENTSTHATMAYNOTHOLDIFCHANGESOCCURINTHEDIMENSIONSOFTHECOMPONENTSINCONTRAST,AKINEMATICJOINTISAGEOMETRICRELATIONSHIPBETWEENTWOCOMPONENTSTHATALLOWSRELATIVEMOTIONANDHOLDSDESPITECHANGESINTHECOMPONENT’SDIMENSIONSTHEKINEMATICJOINTISAFUNCTIONALSPECIFICATION,BUTTHEMATINGCONDITIONISNOTEXAMPLESOFKINEMATICJOINTSARETHEREVOLUTEJOINTANDTHEPRISMATICJOINTAMATINGSURFACEISASURFACEONACOMPONENTTHATISINVOLVEDINAMATINGCONDITIONTHEMATINGSURFACESOFACOMPONENT,OROFAGROUPOFCOMPONENTSCONNECTEDBYKINEMATICJOINTS,CANRESTRICTTHERANGEOFVALUESOFTHECOMPONENTS’DIMENSIONSANDTHEDEGREESOFFREEDOMDOFOFTHEKINEMATICJOINTSASETOFCOMPONENTSTHATARERELATEDBYASETOFKINEMATICJOINTSISAKINEMATICGROUP,ANDASINGLECOMPONENTORAKINEMATICGROUPISACONSTRAINEDGROUPTHETERMCONSTRAINEDGROUPINFERSTHEREAREGEOMETRICRELATIONSHIPSBETWEENTHEMATINGSURFACESTHAT1ARENOTIDENTIFIABLEASASSEMBLYCONSTRAINTS,AND2AREUSEFULINIDENTIFYINGANDFORMULATINGASSEMBLYCONSTRAINTSFORASINGLECOMPONENT,THESEGEOMETRICRELATIONSHIPSARETHECOMPONENT’SDIMENSIONSANDTOLERANCESFORAKINEMATICGROUP,THEYALSOINCLUDETHEDOFOFTHEKINEMATICJOINTSANASSEMBLYCONSTRAINTISCREATEDBYMATINGCONDITIONSCOMPUTERAIDEDDESIGN,VOL30,NO9,PP715–726,1998?1998ELSEVIERSCIENCELTDALLRIGHTSRESERVEDPRINTEDINGREATBRITAIN00104485/98/1900000PIIS0010448598000268715TOWHOMCORRESPONDENCESHOULDBEADDRESSEDTEL7654945720FAX7654940811EMAILDAVEECNPURDUEEDU?STRUCTURALDYNAMICRESEARCHCORPORATION,MILFORD,OH451502789,USA?SCHOOLOFMECHANICALENGINEERING,PURDUEUNIVERSITY,WESTLAFAYETTE,IN479061288,USAPAPERRECEIVED5APRIL1996REVISED10MARCH1998ACCEPTED20MARCH1998MATINGSURFACESOFCOMPONENTACANCOMBINETORESTRICTITSMOTIONINTHETWODIMENSIONALSUBSPACEOFE3DEFINEDBYTHEPLANEOFTHEPAPERNOPAIROFMATINGSURFACESCANRESTRICTTHETRANSLATIONOFTHECOMPONENTINTHISSUBSPACESUCHASETOFMATINGSURFACESISDEFINEDASAPHYSICALLYCONSTRAININGFACESETPCFSTHEPCFSISSIGNIFICANTBECAUSEWITHOUTSUCHASETOFMATINGSURFACES,THECOMPONENTDIMENSIONSINTHECONSTRAINEDGROUPCOULDBECHANGEDWITHOUTREGARDTOTHEOTHERCOMPONENTSINTHEASSEMBLYTHECONSTRAINEDGROUPCOORDINATESYSTEMCOULDTRANSLATEDUETOCHANGESINTHEDIMENSIONSOFANYOFTHECOMPONENTSINTHEASSEMBLYTHENEXTSECTIONDESCRIBESAGENERALMATHEMATICALDEFINITIONOFPCFSTHATWILLENABLETHEIDENTIFICATIONOFGENERALTRANSLATIONALCONSTRAINTSONCOMPONENTSCHARACTERISTICVECTORSPACEEACHMATINGSURFACEHASACHARACTERISTICVECTORCVSPACEOFDIRECTIONSFORWHICHITPREVENTSTRANSLATIONOFTHEASSOCIATEDCONSTRAINEDGROUPFIGURE4DEMONSTRATESTHECVSPACESFORSEVERALT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簡(jiǎn)介：ORIGINALARTICLEASTUDYOFGATELOCATIONOPTIMIZATIONOFPLASTICINJECTIONMOLDINGUSINGSEQUENTIALLINEARPROGRAMMINGMINGZHAIYINGXIERECEIVED18AUGUST2009/ACCEPTED13OCTOBER2009SPRINGERVERLAGLONDONLIMITED2009ABSTRACTAGATELOCATIONISONEOFTHEMOSTIMPORTANTDESIGNVARIABLESCONTROLLINGTHEPRODUCTQUALITYOFINJECTIONMOLDINGINTHISPAPER,THENUMERICALSIMULATIONOFINJECTIONMOLDFILLINGPROCESSISCOMBINEDWITHTHEDESIGNOPTIMIZATIONMETHODTOFINDTHEOPTIMUMGATELOCATIONTOACHIEVEBALANCEDFLOWTHEOBJECTIVEFUNCTIONISEXPRESSEDINTERMSOFTHEDIFFERENCEBETWEENTHEMAXIMUMANDMINIMUMTIMESOFBOUNDARYFILLINGTHECOORDINATESOFGATEARECHOSENASDESIGNVARIABLES,ANDACONSTRAINTISEMPLOYEDTOLIMITTHECLAMPFORCELOWERTHANTHEREFERENCEVALUETHEOPTIMIZATIONPROBLEMISSOLVEDWITHTHESEQUENTIALLINEARPROGRAMMINGALGORITHM,ANDDESIGNSENSITIVITIESAREEVALUATEDVIATHEFINITEDIFFERENCEAPPROXIMATIONFINALLY,NUMERICALEXAMPLESAREGIVENTODEMONSTRATETHEEFFECTOFPROPOSEDMETHODSKEYWORDSINJECTIONMOLDINGGATELOCATIONOPTIMALDESIGNFLOWBALANCE1INTRODUCTIONINJECTIONMOLDINGISBYFARTHEMOSTPOPULARPROCESSFORTHEPRODUCTIONOFPLASTICPARTSASTHEINJECTIONMOLDINGPRODUCTIONISDOMINATEDBYCOMPLEXPROCESSDYNAMICS,ITISDIFFICULTTOFULLYUNDERSTANDANDPREDICTTHEFINALPARTQUALITYTHATISRELATEDTOVARIOUSMOLDINGPARAMETERSINTHEPASTTHREEDECADES,THENUMERICALSIMULATIONOFINJECTIONMOLDINGHASBEENGREATLYDEVELOPEDBYCLEARUNDERSTANDINGCHARACTERISTICSOFFLOWINGANDHEATTRANSFEROFPOLYMERMELTSTOPREDICATETHEQUALITYCHARACTERISTICSOFINJECTIONMOLDEDPARTSWITHOUTACTUALLYFABRICATINGAMOLDHOWEVER,THECOMPUTERAIDEDENGINEERINGCAESIMULATIONREQUIRESTHEMOLDDESIGNERTORUNTHESIMULATION,PERFORMTHEDESIGNEVALUATION,ANDREDESIGNBASEDONEXPERIENCE,UNTILASATISFACTORYDESIGNISOBTAINEDTHISMANUALDESIGNPROCESSDOESNOTGUARANTEETHEOPTIMALDESIGNSOLUTIONANDSOHASLEDTOINCREASINGINTERESTINTHEUTILIZATIONOFDESIGNOPTIMIZATIONTECHNIQUESINTHEMOLDDESIGNPROCEDURESEVERALSTUDIESREPORTEDHAVEINVESTIGATEDTHEOPTIMIZATIONOFTHEINJECTIONMOLDINGPROCESSPANDELIDISANDZHOU1PRESENTEDTHEOPTIMIZATIONOFGATELOCATIONUSINGTHECOMBINEDSCHEMEOFASIMULATEDANNEALINGANDHILLCLIMBINGMETHODTHEQUALITYOFAGATINGDESIGNWASPRESENTEDASANADDITIVEFUNCTIONOFATEMPERATUREDIFFERENTIALTERMANDANOVERPACKTERM,WITHAPPROPRIATEWEIGHTINGTERMYOUNG2DEVELOPEDAMETHODOFGATELOCATIONOPTIMIZATIONBASEDONTHEMINIMIZATIONOFTHEMOLDFILLINGPRESSURE,UNEVENFILLINGPATTERN,ANDTEMPERATUREDIFFERENCEDURINGTHEMOLDFILLINGPROCESSYEETAL3DEVELOPEDASCHEMETOOPTIMIZETHEPARTQUALITYININJECTIONMOLDINGAMATHEMATICALDEFINITIONOFPARTWARPAGEISPRESENTED,ANDSIMULATEDANNEALINGMETHODISUSEDTOSEARCHFOROPTIMUMPROCESSCONDITIONCHANGETAL4COMBINEDTHEUSAGEOFTAGUCHIAPPROACHANDCAEFLOWSIMULATIONSOFTWAREFOROPTIMALDESIGNOFINJECTIONMOLDINGPROCESSPARAMETERSIRANIETAL5DEVELOPEDASYSTEMTHATAUTOMATESTHEPROCESSOFGATEDESIGNTHEGATEDESIGNISPERFORMEDINTWOSTAGES,GLOBALSEARCHFOLLOWEDBYALOCALSEARCHDURINGTHEGLOBALSEARCH,THECANDIDATEGATINGPLANSAREGENERATEDUSINGFEATURECONNECTIVITYINFORMATIONTHESEGATINGPLANSAREEVALUATEDANDREDESIGNEDINITERATIVEUNTILTHEBESTCAVITYINLETCONDITIONSFOREACHPLANISOBTAINEDTHEN,THEBESTINTHETRIALSETISPERTURBEDLOCALLYINASEARCHFORABETTERGATINGPLANTHELIMITATIONOFTHISSYSTEMISTHATTHEFEATURESUSEDAREVERYSIMPLEGEOMETRYZHAIETAL6–9HASINVESTIGATEDTHEOBJECTIVEFUNCTIONANDSEARCHSCHEMEMZHAIYXIEDEPARTMENTOFENGINEERINGMECHANICS,ZHENGZHOUUNIVERSITY,ZHENGZHOU450002,PEOPLE’SREPUBLICOFCHINAEMAILMMZHAIHOTMAILCOMINTJADVMANUFTECHNOLDOI101007/S0017000923761THEMOSTIMPORTANTVARIABLESOFTHETOTALMOLDDESIGN,ANDITISNECESSARYTOSEARCHFORANOPTIMUMGATELOCATIONTOIMPROVEPARTQUALITYINTHISCONTEXT,THEOPTIMIZATIONOFGATELOCATIONISSTUDIEDAGATEISMODELEDASPOINTSOURCES,ANDCOORDINATESOFTHEGATELOCATIONARESELECTEDASDESIGNVARIABLESTOAPPLYOPTIMIZATIONTHEORYTOTHEINJECTIONMOLDINGPROCESS,QUANTITATIVEMEASUREOFTHEPARTQUALITYFIRSTNEEDTOBEDEVELOPEDSINCETHEULTIMATEGOALINOPTIMIZINGTHEINJECTIONMOLDINGDESIGNISTOIMPROVEPARTQUALITYTHEPARTQUALITYCANBEDESCRIBEDWITHMANYENDPRODUCTPROPERTIESSUCHASMECHANICAL,THERMAL,ELECTRICAL,OPTICAL,ORGEOMETRICALPROPERTIESTHEREARETWOTYPESOFPARTQUALITYMEASURESDIRECTANDINDIRECTMETHODDIRECTMETHODCANDETERMINETHEMEASURABLEQUANTITIESTHATCHARACTERIZEAPRODUCTINCONTRAST,ANINDIRECTMEASUREOFQUALITYISAQUANTITYTHATISCORRELATEDBUTDOESNOTPRODUCEADIRECTESTIMATEOFTHATQUALITYTHEINDIRECTQUALITYMEASURESUSEDINTHISPAPERARETHOSERELATEDTOWARPAGEPARTWARPAGE,ADIMENSIONALDISTORTIONTHATCAUSESSTRUCTURALUNFITNESSANDESTHETICPROBLEMS,ISONEOFTHECRITICALQUALITYISSUESFORINJECTIONMOLDEDPARTSWHENTHEMOLDEDPARTDOESNOTSATISFYADIMENSIONALTOLERANCE,ITISUSELESSASTHEFINALPRODUCTAMAJORCAUSEOFPARTWARPAGEISTHERESIDUALSTRESSESINDUCEDBYUNBALANCEDFILLINGWHENSUCHRESIDUALSTRESSHASNOCHANCETORELAX,THEPLASTICPARTSWILLGRADUALLYWARPUPONEJECTIONASTIMEPASSESFORTHISREASON,ACHIEVINGBALANCEDFLOWISTHEOBJECTIVEOFTHEOPTIMIZATIONSCHEMEINTHISSTUDYLAMETAL13,14HAVEDEVELOPEDTHEFLOWPATHCONCEPTFORCAVITYBALANCINGFORPLASTICINJECTIONMOLDING,FLOWPATHISDEFINEDASTHEPATHTRACEDBYAMELTPARTICLEWHENITISFIRSTINJECTEDINTOACAVITYUNTILTHEMOLDCAVITYHASBEENCOMPLETELYFILLEDITMAYBEVISUALIZEDASTHETRAJECTORYFROMTHEINJECTIONGATETOTHEEXTREMITIESOFTHECAVITYANAUTOMATICFLOWPATHGENERATIONROUTINEWASDEVELOPED15,16FORTHEPARTWITHUNIFORMTHICK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簡(jiǎn)介：TOURISMEDUCATIONANDTRAININGINTHECARIBBEANPREPARINGFORTHE21STCENTURYKWAMERCHARLESUNIVERSITYOFTHEWESTINDIES,INSTITUTEOFBUSINESS,TRINIDADANDTOBAGOABSTRACTTHISPAPERREVIEWSTHECURRENTSTATEOFTOURISMANDHOSPITALITYEDUCATIONANDTRAININGINTHECARIBBEANTOURISMEDUCATIONANDTRAININGAREEXAMINEDATTHEPUBLICSCHOOL,POSTSECONDARYANDTERTIARYLEVELSTHEIMPORTANCEOFHUMANRESOURCEDEVELOPMENTTOTHEECONOMICVIABILITYOFCARIBBEANTOURISMANDTHECARIBBEANASAWHOLEISHIGHLIGHTED,ASISTHENEEDTOADOPTASTRATEGICAPPROACHTOTOURISMEDUCATIONANDTRAININGONTHEPARTOFBOTHEDUCATORSANDPOLICYMAKERSITISALSOSUGGESTEDTHATTHECARIBBEANMUSTPREPAREFORTOURISMINTHE21STCENTURYTHROUGHPROPERSELECTIONOFPEOPLEFORTHEINDUSTRYANDTHROUGHQUALITYEDUCATIONALANDTRAININGOPPORTUNITIES?1997BYJOHNWILEYACCEPTED4NOVEMBER1996PROGRTOURISMHOSPITRES3,189–1971997NOOFFIGURES1NOOFTABLES2NOOFREFS15KEYWORDSCARRIBEANTOURISMEDUCATIONANDTRAININGECONOMICDEVELOPMENTINTRODUCTIONTHECARIBBEANREGIONENCOMPASSESTHEARCHIPELAGICARCOFISLANDSSTARTINGWITHTHEBAHAMASINTHENORTH,JUSTOFFTHECOASTOFFLORIDA,USA,ANDENDINGWITHTRINIDADANDTOBAGOINTHESOUTH,JUSTOFFTHECOASTOFVENEZUELA,SOUTHAMERICAITALSOINCLUDESTHEMAINLANDSHORESWASHEDBYTHECARIBBEANSEAINCENTRALANDSOUTHAMERICAFIG1THEREGIONCOMPRISESFORMEREUROPEANCOLONIESOFTHENEWWORLD‘DISCOVERED’BYCOLUMBUS500YEARSAGOITSINHABITANTS,THEREFORE,SPEAKEUROPEANLANGUAGES,INCLUDINGSPANISH,ENGLISH,FRENCHANDDUTCHALMOSTEVERYPARTOFTHECARIBBEANPOSSESSESYEARROUND‘SUN,SEAANDSAND’ANDINADDITION,MANYOFTHECOUNTRIESBOASTOFEXOTICFLORAANDFUANA,CORALSEASANDRAINFORESTSTHECARIBBEANTHEREFORECATERSTOMANYMARKETNICHESTOURISMINTHECARIBBEANTOURISMISTHELIFEBLOODOFMANYOFTHECOUNTRIESOFTHECARIBBEANIN1994,TOURISTEXPENDITUREACCOUNTEDFOROVERONETHIRDOFTHEGROSSDOMESTICPRODUCTGDPOFFOUROFTHE12MEMBERCOUNTRIESOFTHECARIBBEANTOURISMORGANIZATIONCTOFORWHICHDATAAREAVAILABLEINTHECASEOFANTIGUAANDBARBUDA,TOURISMACCOUNTEDFORASMUCHAS93OFGDPVISITORPERCAPITAEXPENDITUREIN1994WASOVERUS1,000FOR17OFTHECTOMEMBERCOUNTRIES,ANDWASASHIGHASUS12,370FORONECOUNTRY,STMAARTENCTO,1995SEETABLES1AND2IN1994,CLOSETO14MILLIONVISITORSCAMETOTHECARIBBEANANDSPENTINEXCESSOFUS11BILLIONTHISISANINCREASEOFALMOSTAMILLIONPEOPLEANDCORRESPONDENCETOKRCHARLESPROGRESSINTOURISMANDHOSPITALITYRESEARCH,VOL3,189–1971997CCC1077–3509/97/030189–091750?1997BYJOHNWILEYAIRLINEPERSONNELTAXIDRIVERSWORKERSINBARS,RESTAURANTS,CASINOS,RETAILSTORESANDOTHERRELATEDINDUSTRIESANDPUBLICSERVANTSEMPLOYEDINRELEVANTPARTSOFTHEGOVERNMENTWHENALLOFTHESEWORKERSAREAGGREGATED,WEFINDTHATALARGEPROPORTIONOFTHEREGION’SLABOURFORCEISDIRECTLYORINDIRECTLYDEPENDENTONTOURISMFORTHEIRLIVELIHOODTHISGIVESTHETOURISMINDUSTRYTHEPOTENTIALOFBEINGTHELARGESTSINGLEEMPLOYEROFPEOPLEINTHEREGIONTHECRITICALIMPORTANCEOFTOURISMTOTHECARIBBEAN,THEINCREASEINWORLDTOURISMANDINTOURISTDEMANDFORQUALITYGOODSANDSERVICES,THECONCOMITANTREQUIREMENTFORTOURISTDESTINATIONSSUCHASTHECARIBBEANTODELIVERQUALITYSERVICEANDPRODUCTS,ANDTHELABOURINTENSIVENATUREOFTHEINDUSTRY,ALLSUGGESTTHENEEDFORAWELLEDUCATEDANDTRAINEDCADREOFHOSPITALITYANDTOURISMPROFESSIONALSTHIS,INTURN,SUGGESTSTHATEDUCATIONANDTRAININGINTOURISMAREVITALTOTHEDEVELOPMENTOFTHEINDUSTRYINTHEREGIONCONLIN,1993INTHECARIBBEAN,TOURISMEDUCATIONANDTRAININGNEEDSCANBEIDENTIFIEDATTHREETABLE1VISITOREXPENDITUREASAPERCENTAGEOFGROSSDOMESTICPRODUCTINTHECARIBBEANREGIONCOUNTRY19931994ANGUILLA83879140ANTIGUAANDBARBUDA96089327ARUBANANABAHAMAS4254NABARBADOS37834088BELIZE15561588BERMUDA32843207CAYMANISLANDSNANACUBANANACURACAO1572NADOMINICA1902NADOMINICANREPUBLIC12631178GRENADANANAGUYANA11381071HAITI509513JAMAICANANAMARTINIQUENANAMONTSERRAT2921NAPUERTORICO442442STKITTSANDNEVISNANASTLUCIA58955832STVINCENTANDGRENADINES25052297SURINAMENANATRINIDADANDTOBAGO185173TURKSANDCAICOSISLANDSNANAUSVIRGINISLANDSNANAVENEZUELANANANANOTAVAILABLESOURCECARIBBEANTOURISMSTATISTICALREPORT1994,CARIBBEANTOURISMORGANIZATION,BARBADOS1995TABLE2VISITOREXPENDITUREPERCAPITAUSDOLLARSINTHECARIBBEANREGIONCOUNTRY19931994ANGUILLA46815346ANTIGUAANDBARBUDA58116133ARUBA62055712BAHAMAS48484881BARBADOS20042263BELIZE340355BERMUDA85328808BONAIRE29412807BRITISHVIRGINISLANDS1035610456CAYMANISLANDS924110943CUBA6678CURACAO16421684DOMINICA383419DOMINICANREPUBLIC153160GRENADA498615GUADELOUPE785961GUYANA5961HAITI77JAMAICA381371MARTINIQUE9211053MONTSERRAT17001850PUERTORICO450471STKITTSANDNEVIS17271814STLUCIA15801571STMAARTEN118062370STVINCENTANDGRENADINES474457SURINAME2726TRINIDADANDTOBAGO6664TURKSANDCAICOSISLANDS40774346USVIRGINISLANDS83288427VENEZUELANANANANOTAVAILABLESOURCECARIBBEANTOURISMSTATISTICALREPORT1994,CARIBBEANTOURISMORGANIZATION,BARBADOS1995TOURISMEDUCATIONANDTRAININGINTHECARIBBEAN191?1997BYJOHNWILEYSONS,LTDPROGRESSINTOURISMANDHOSPITALITYRESEARCH,VOL3,189–1971997