簡介：SAMPLEDDATAMODELPREDICTIVECONTROLFORNONLINEARTIMEVARYINGSYSTEMSSTABILITYANDROBUSTNESS?FERNANDOACCFONTES1,LALOMAGNI2,AND′EVAGYURKOVICS31OFFICINAMATHEMATICA,DEPARTAMENTODEMATEM′ATICAPARAACI?ENCIAETECNOLOGIA,UNIVERSIDADEDOMINHO,4800058GUIMAR?AES,PORTUGALFFONTESMCTUMINHOPT2DIPARTIMENTODIINFORMATICAESISTIMISTICA,UNIVERSITADEGLISTUDIDIPAVIA,VIAFERRATA1,27100PAVIA,ITALYLALOMAGNIUNIPVIT3BUDAPESTUNIVERSITYOFTECHNOLOGYANDECONOMICS,INSTITUTEOFMATHEMATICS,BUDAPESTH1521,HUNGARYGYEMATHBMEHUSUMMARYWEDESCRIBEHEREASAMPLEDDATAMODELPREDICTIVECONTROLFRAMEWORKTHATUSESCONTINUOUSTIMEMODELSBUTTHESAMPLINGOFTHEACTUALSTATEOFTHEPLANTASWELLASTHECOMPUTATIONOFTHECONTROLLAWS,ARECARRIEDOUTATDISCRETEINSTANTSOFTIMETHISFRAMEWORKCANADDRESSAVERYLARGECLASSOFSYSTEMS,NONLINEAR,TIMEVARYING,ANDNONHOLONOMICASINMANYOTHERSSAMPLEDDATAMODELPREDICTIVECONTROLSCHEMES,BARBALAT’SLEMMAHASANIMPORTANTROLEINTHEPROOFOFNOMINALSTABILITYRESULTSITISARGUEDTHATTHEGENERALIZATIONOFBARBALAT’SLEMMA,DESCRIBEDHERE,CANHAVEALSOASIMILARROLEINTHEPROOFOFROBUSTSTABILITYRESULTS,ALLOWINGALSOTOADDRESSAVERYGENERALCLASSOFNONLINEAR,TIMEVARYING,NONHOLONOMICSYSTEMS,SUBJECTTODISTURBANCESTHEPOSSIBILITYOFTHEFRAMEWORKTOACCOMMODATEDISCONTINUOUSFEEDBACKSISESSENTIALTOACHIEVEBOTHNOMINALSTABILITYANDROBUSTSTABILITYFORSUCHGENERALCLASSESOFSYSTEMS1INTRODUCTIONMANYMODELPREDICTIVECONTROLMPCSCHEMESDESCRIBEDINTHELITERATUREUSECONTINUOUSTIMEMODELSANDSAMPLETHESTATEOFTHEPLANTATDISCRETEINSTANTSOFTIMESEEEG3,7,9,13ANDALSO6THEREAREMANYADVANTAGESINCONSIDERINGACONTINUOUSTIMEMODELFORTHEPLANTNEVERTHELESS,ANYIMPLEMENTABLEMPCSCHEMECANONLYMEASURETHESTATEANDSOLVEANOPTIMIZATIONPROBLEMATDISCRETEINSTANTSOFTIMEINALLTHEREFERENCESCITEDABOVE,BARBALAT’SLEMMA,ORAMODIFICATIONOFIT,ISUSEDASANIMPORTANTSTEPTOPROVESTABILITYOFTHEMPCSCHEMESBARBALAT’S?THEFINANCIALSUPPORTFROMMURSTPROJECT“NEWTECHNIQUESFORTHEIDENTIFICATIONANDADAPTIVECONTROLOFINDUSTRIALSYSTEMS”,FROMFCTPROJECTPOCTI/MAT/61842/2004,ANDFROMTHEHUNGARIANNATIONALSCIENCEFOUNDATIONFORSCIENTIFICRESEARCHGRANTNOT037491ISGRATEFULLYACKNOWLEDGEDRFINDEISENETALEDSASSESSMENTANDFUTUREDIRECTIONS,LNCIS358,PP115–129,2007SPRINGERLINKCOMC?SPRINGERVERLAGBERLINHEIDELBERG2007SAMPLEDDATAMPCFORNONLINEARTIMEVARYINGSYSTEMS117ATTIMET0,AGIVENFUNCTIONFIRIRNIRM→IRN,ANDASETU?IRMOFPOSSIBLECONTROLVALUESWEASSUMETHISSYSTEMTOBEASYMPTOTICALLYCONTROLLABLEONX0ANDTHATFORALLT≥0FT,0,00WEFURTHERASSUMETHATTHEFUNCTIONFISCONTINUOUSANDLOCALLYLIPSCHITZWITHRESPECTTOTHESECONDARGUMENTTHECONSTRUCTIONOFTHEFEEDBACKLAWISACCOMPLISHEDBYUSINGASAMPLEDDATAMPCSTRATEGYCONSIDERASEQUENCEOFSAMPLINGINSTANTSΠ{TI}I≥0WITHACONSTANTINTERSAMPLINGTIMEΔ0SUCHTHATTI1TIΔFORALLI≥0CONSIDERALSOTHECONTROLHORIZONANDPREDICTIVEHORIZON,TCANDTP,WITHTP≥TCΔ,ANDANAUXILIARYCONTROLLAWKAUXIRIRN→IRMTHEFEEDBACKCONTROLISOBTAINEDBYREPEATEDLYSOLVINGONLINEOPENLOOPOPTIMALCONTROLPROBLEMSPTI,XTI,TC,TPATEACHSAMPLINGINSTANTTI∈Π,EVERYTIMEUSINGTHECURRENTMEASUREOFTHESTATEOFTHEPLANTXTIPT,XT,TC,TPMINIMIZETTP?TLS,XS,USDSWTTP,XTTP,2SUBJECTTO˙XSFS,XS,USAES∈T,TTP,3XTXT,XS∈XFORALLS∈T,TTP,US∈UAES∈T,TTC,USKAUXS,XSAES∈TTC,TTP,XTTP∈S4NOTETHATINTHEINTERVALTTC,TTPTHECONTROLVALUEISSELECTEDFROMASINGLETONANDTHEREFORETHEOPTIMIZATIONDECISIONSAREALLCARRIEDOUTINTHEINTERVALT,TTCWITHTHEEXPECTEDBENEFITSINTHECOMPUTATIONALTIMETHENOTATIONADOPTEDHEREISASFOLLOWSTHEVARIABLETREPRESENTSREALTIMEWHILEWERESERVESTODENOTETHETIMEVARIABLEUSEDINTHEPREDICTIONMODELTHEVECTORXTDENOTESTHEACTUALSTATEOFTHEPLANTMEASUREDATTIMETTHEPROCESSX,UISAPAIRTRAJECTORY/CONTROLOBTAINEDFROMTHEMODELOFTHESYSTEMTHETRAJECTORYISSOMETIMESDENOTEDASS?→XST,XT,UWHENWEWANTTOMAKEEXPLICITTHEDEPENDENCEONTHEINITIALTIME,INITIALSTATE,ANDCONTROLFUNCTIONTHEPAIRˉX,ˉUDENOTESOUROPTIMALSOLUTIONTOANOPENLOOPOPTIMALCONTROLPROBLEMTHEPROCESSX?,U?ISTHECLOSEDLOOPTRAJECTORYANDCONTROLRESULTINGFROMTHEMPCSTRATEGYWECALLDESIGNPARAMETERSTHEVARIABLESPRESENTINTHEOPENLOOPOPTIMALCONTROLPROBLEMTHATARENOTFROMTHESYSTEMMODELIEVARIABLESWEAREABLETOCHOOSETHESECOMPRISETHECONTROLHORIZONTC,THEPREDICTIONHORIZONTP,THERUNNINGCOSTANDTERMINALCOSTSFUNCTIONSLANDW,THEAUXILIARYCONTROLLAWKAUX,ANDTHETERMINALCONSTRAINTSETS?IRN

簡介：APOWEREFFICIENTCMOSUWBSIGNALGENERATIONMODULERUIXU,YALINJIN,ANDCAMNGUYEN?DEPARTMENTOFELECTRICALANDCOMPUTERENGINEERINGTEXASAMUNIVERSITY,COLLEGESTATION,TEXAS77843,USAABSTRACTTHISPAPERPRESENTSANEWCARRIERBASEDULTRAWIDEBANDUWBTRANSMITTERARCHITECTUREANDITSCMOSIMPLEMENTATIONTHENEWTRANSMITTERTOPOLOGYADOPTSADOUBLESTAGESWITCHINGTOENHANCERFPOWEREFFICIENCY,REDUCEDCPOWERCONSUMPTIONANDCIRCUITCOMPLEXITYFABRICATEDUSINGA018ΜMCMOSPROCESS,THEUWBSIGNALGENERATIONMODULEINCLUDESANUWBSUBNANOSECONDSWITCHINGSINGLEPOLESINGLETHROWSPSTSWITCHANDATUNABLEIMPULSEGENERATORMEASUREMENTRESULTSSHOWTHATTHEGENERATEDUWBSIGNALHASVARIABLE10DBSIGNALBANDWIDTHSFROM05TO4GHZANDTUNABLECENTRALFREQUENCYCOVERINGTHEENTIREUWBFREQUENCYRANGEOF31TO106GHZTHECMOSMODULECONSUMESLESSTHAN2MWDCPOWERTHEPROPOSEDCARRIERBASEDUWBTRANSMITTERANDTHEDEMONSTRATEDMODULEPROVIDEANATTRACTIVEMEANSFORUWBSIGNALGENERATIONFORBOTHUWBCOMMUNICATIONSANDRADARAPPLICATIONS1INTRODUCTIONULTRAWIDEBANDUWBTECHNOLOGYHASRECEIVEDSIGNIFICANTINTERESTS,PARTICULARLYAFTERTHEFCC’SNOTICEOFINQUIRYIN19981ANDREPORTANDORDERIN20022FORUNLICENSEDUSESOFUWBDEVICESWITHINTHE31–106GHZFREQUENCYBANDUWBTECHNIQUESAREPROMISINGTECHNOLOGY,CAPABLEOFBOTHACCURATEPOSITIONLOCATIONANDHIGHRATE,SHORTRANGEADHOCNETWORKINGASWELLASHIGHRESOLUTIONSENSINGCARRIERBASEDUWBSIGNALSHAVEBEENWIDELYUSEDINVARIOUSRADARANDCOMMUNICATIONAPPLICATIONS3–4THEYHOLDTHEADVANTAGEOFMORECONVENIENTSPECTRUMMANAGEMENTANDLESSDISTORTIONTHROUGHANTENNAS5INTYPICALUWBTRANSMITTERS,THEGENERATEDCARRIERBASEDUWBVOLTAGESIGNALNEEDSTOBESENTTOAWIDEBANDPOWERAMPLIFIERPATOACHIEVETHEREQUIREDPOWERLEVELTHISAPPROACHSUFFERSFROMTWOMAJORDISADVANTAGESTHEDESIGNCHALLENGESOFAUWBPAANDLOWPOWEREFFICIENCYINLOWPULSEREPETITIONFREQUENCYPRFSITUATIONINTHISPAPER,WEPROPOSEANEWARCHITECTUREFORCARRIERBASEDUWBTRANSMITTERTHATISNOTONLYPOWEREFFICIENT,BUTALSOREDUCESCIRCUITCOMPLEXITY6WEALSODEMONSTRATETHEFIG1THEPROPOSEDCARRIERBASEDUWBTRANSMITTERTOPOLOGY3211424408784/07/2000?2007IEEE7THISMETHODOFPULSEGENERATIONISESPECIALLYATTRACTIVEFORTHEPROPOSEDTRANSMITTERBECAUSEITCANPROVIDEFULLVOLTAGESWINGREQUIREDFORTHESPSTSWITCHOPERATION5MEASUREMENTRESULTSTHECMOSPULSEGENERATORSPSTSWITCHCHIPWASUSEDINCONJUNCTIONWITHANEXTERNALFREQUENCYSYNTHESIZERTODEMONSTRATETHENEWCARRIERBASEDUWBTRANSMITTERTHECMOSCHIP’SMICROPHOTOGRAPHISDISPLAYEDINFIG4THEDIEAREAOFTHEENTIRECIRCUITIS850ΜMBY700ΜM,INCLUDINGTHEINPUTANDOUTPUTONWAFERPADSUNDERA18VSUPPLYVOLTAGE,THEWHOLEMODULECONSUMESLESSTHAN1MADCCURRENTFIG5ADISPLAYSTHETIMEDOMAINWAVEFORMOFAUWBSIGNALWITH2NSDURATIONAND5GHZCENTERFREQUENCYTHESIGNALAMPLITUDEIS2VPPPEAKTOPEAKBYINCREASINGTHEEXTERNALBIASINGVOLTAGEFORTHEPULSEGENERATOR,THEPULSEWIDTHOFTHEUWBSIGNALCANBEREDUCEDWHENTHEPULSEWIDTHISREDUCEDTOACERTAINVALUE,THEAMPLITUDEOFTHEFIG3CMOSIMPULSEGENERATIONUSINGDIGITALLOGICS15105005115048121620TIMENSAMPLITUDEVFREQUENCYGHZAMPLITUDEDBMABFIG5AMEASUREDTIMEDOMAINUWBSIGNALWITH05NSDURATIONBMEASUREDSPECTRUMSOFUWBSIGNALSCOVERINGTHE31106GHZUWBBANDFIG4MICROPHOTOGRAPHOFTHE018ΜMCMOSCHIPINTEGRATINGTHEPULSEGENERATORANDTHESPSTSWITCH323

簡介：DOI101007/S0017000423288ORIGINALARTICLEINTJADVMANUFTECHNOL20062861–66FANGJUNGSHIOUCHAOCHANGACHENWENTULIAUTOMATEDSURFACEFINISHINGOFPLASTICINJECTIONMOLDSTEELWITHSPHERICALGRINDINGANDBALLBURNISHINGPROCESSESRECEIVED30MARCH2004/ACCEPTED5JULY2004/PUBLISHEDONLINE30MARCH2005?SPRINGERVERLAGLONDONLIMITED2005ABSTRACTTHISSTUDYINVESTIGATESTHEPOSSIBILITIESOFAUTOMATEDSPHERICALGRINDINGANDBALLBURNISHINGSURFACEFINISHINGPROCESSESINAFREEFORMSURFACEPLASTICINJECTIONMOLDSTEELPDS5ONACNCMACHININGCENTERTHEDESIGNANDMANUFACTUREOFAGRINDINGTOOLHOLDERHASBEENACCOMPLISHEDINTHISSTUDYTHEOPTIMALSURFACEGRINDINGPARAMETERSWEREDETERMINEDUSINGTAGUCHI’SORTHOGONALARRAYMETHODFORPLASTICINJECTIONMOLDINGSTEELPDS5ONAMACHININGCENTERTHEOPTIMALSURFACEGRINDINGPARAMETERSFORTHEPLASTICINJECTIONMOLDSTEELPDS5WERETHECOMBINATIONOFANABRASIVEMATERIALOFPAAL2O3,AGRINDINGSPEEDOF18000RPM,AGRINDINGDEPTHOF20ΜM,ANDAFEEDOF50MM/MINTHESURFACEROUGHNESSRAOFTHESPECIMENCANBEIMPROVEDFROMABOUT160ΜMTO035ΜMBYUSINGTHEOPTIMALPARAMETERSFORSURFACEGRINDINGSURFACEROUGHNESSRACANBEFURTHERIMPROVEDFROMABOUT0343ΜMTO006ΜMBYUSINGTHEBALLBURNISHINGPROCESSWITHTHEOPTIMALBURNISHINGPARAMETERSAPPLYINGTHEOPTIMALSURFACEGRINDINGANDBURNISHINGPARAMETERSSEQUENTIALLYTOAFINEMILLEDFREEFORMSURFACEMOLDINSERT,THESURFACEROUGHNESSRAOFFREEFORMSURFACEREGIONONTHETESTEDPARTCANBEIMPROVEDFROMABOUT215ΜMTO007ΜMKEYWORDSAUTOMATEDSURFACEFINISHINGBALLBURNISHINGPROCESSGRINDINGPROCESSSURFACEROUGHNESSTAGUCHI’SMETHOD1INTRODUCTIONPLASTICSAREIMPORTANTENGINEERINGMATERIALSDUETOTHEIRSPECIFICCHARACTERISTICS,SUCHASCORROSIONRESISTANCE,RESISTANCETOCHEMICALS,LOWDENSITY,ANDEASEOFMANUFACTURE,ANDHAVEINCREASINGLYFJSHIOUUCCACHENWTLIDEPARTMENTOFMECHANICALENGINEERING,NATIONALTAIWANUNIVERSITYOFSCIENCEANDTECHNOLOGY,NO43,SECTION4,KEELUNGROAD,106TAIPEI,TAIWANROCEMAILSHIOUMAILNTUSTEDUTWTEL886227376543FAX886227376460REPLACEDMETALLICCOMPONENTSININDUSTRIALAPPLICATIONSINJECTIONMOLDINGISONEOFTHEIMPORTANTFORMINGPROCESSESFORPLASTICPRODUCTSTHESURFACEFINISHQUALITYOFTHEPLASTICINJECTIONMOLDISANESSENTIALREQUIREMENTDUETOITSDIRECTEFFECTSONTHEAPPEARANCEOFTHEPLASTICPRODUCTFINISHINGPROCESSESSUCHASGRINDING,POLISHINGANDLAPPINGARECOMMONLYUSEDTOIMPROVETHESURFACEFINISHTHEMOUNTEDGRINDINGTOOLSWHEELSHAVEBEENWIDELYUSEDINCONVENTIONALMOLDANDDIEFINISHINGINDUSTRIESTHEGEOMETRICMODELOFMOUNTEDGRINDINGTOOLSFORAUTOMATEDSURFACEFINISHINGPROCESSESWASINTRODUCEDIN1AFINISHINGPROCESSMODELOFSPHERICALGRINDINGTOOLSFORAUTOMATEDSURFACEFINISHINGSYSTEMSWASDEVELOPEDIN2GRINDINGSPEED,DEPTHOFCUT,FEEDRATE,ANDWHEELPROPERTIESSUCHASABRASIVEMATERIALANDABRASIVEGRAINSIZE,ARETHEDOMINANTPARAMETERSFORTHESPHERICALGRINDINGPROCESS,ASSHOWNINFIG1THEOPTIMALSPHERICALGRINDINGPARAMETERSFORTHEINJECTIONMOLDSTEELHAVENOTYETBEENINVESTIGATEDBASEDINTHELITERATUREINRECENTYEARS,SOMERESEARCHHASBEENCARRIEDOUTINDETERMININGTHEOPTIMALPARAMETERSOFTHEBALLBURNISHINGPROCESSFIG2FORINSTANCE,ITHASBEENFOUNDTHATPLASTICDEFORMATIONONTHEWORKPIECESURFACECANBEREDUCEDBYUSINGATUNGSTENCARBIDEBALLORAROLLER,THUSIMPROVINGTHESURFACEROUGHNESS,SURFACEHARDNESS,ANDFATIGUERESISTANCE3–6THEBURNISHINGPROCESSISACCOMPLISHEDBYMACHININGCENTERS3,4ANDLATHES5,6THEMAINBURNISHINGPARAMETERSHAVINGSIGNIFICANTEFFECTSONTHESURFACEROUGHNESSAREBALLORROLLERMATERIAL,BURNISHINGFORCE,FEEDRATE,BURNISHINGSPEED,LUBRICATION,ANDNUMBEROFBURNISHINGPASSES,AMONGOTHERS3THEOPTIMALSURFACEBURNISHINGPARAMETERSFORTHEPLASTICINJECTIONMOLDSTEELPDS5WEREACOMBINATIONOFGREASELUBRICANT,THETUNGSTENCARBIDEBALL,ABURNISHINGSPEEDOF200MM/MIN,ABURNISHINGFORCEOF300N,ANDAFEEDOF40ΜM7THEDEPTHOFPENETRATIONOFTHEBURNISHEDSURFACEUSINGTHEOPTIMALBALLBURNISHINGPARAMETERSWASABOUT25MICRONSTHEIMPROVEMENTOFTHESURFACEROUGHNESSTHROUGHBURNISHINGPROCESSGENERALLYRANGEDBETWEEN40AND903–7THEAIMOFTHISSTUDYWASTODEVELOPSPHERICALGRINDINGANDBALLBURNISHINGSURFACEFINISHPROCESSESOFAFREEFORMSURFACE63FIG4SCHEMATICILLUSTRATIONOFTHESPHERICALGRINDINGTOOLANDITSADJUSTMENTDEVICE3PLANNINGOFTHEMATRIXEXPERIMENT31CONFIGURATIONOFTAGUCHI’SORTHOGONALARRAYTHEEFFECTSOFSEVERALPARAMETERSCANBEDETERMINEDEFFICIENTLYBYCONDUCTINGMATRIXEXPERIMENTSUSINGTAGUCHI’SORTHOGONALARRAY8TOMATCHTHEAFOREMENTIONEDSPHERICALGRINDINGPARAMETERS,THEABRASIVEMATERIALOFTHEGRINDERBALLWITHTHEDIAMETEROF10MM,THEFEEDRATE,THEDEPTHOFGRINDING,ANDTHEREVOLUTIONOFTHEELECTRICGRINDERWERESELECTEDASTHEFOUREXPERIMENTALFACTORSPARAMETERSANDDESIGNATEDASFACTORATODSEETABLE1INTHISRESEARCHTHREELEVELSSETTINGSFOREACHFACTORWERECONFIGUREDTOCOVERTHERANGEOFINTEREST,ANDWEREIDENTIFIG5APHOTOOFTHESPHERICALGRINDINGTOOLBPHOTOOFTHEBALLBURNISHINGTOOLTABLE1THEEXPERIMENTALFACTORSANDTHEIRLEVELSFACTORLEVEL123AABRASIVEMATERIALSICAL2O3,WAAL2O3,PABFEEDMM/MIN50100200CDEPTHOFGRINDINGΜM205080DREVOLUTIONRPM120001800024000FIEDBYTHEDIGITS1,2,AND3THREETYPESOFABRASIVEMATERIALS,NAMELYSILICONCARBIDESIC,WHITEALUMINUMOXIDEAL2O3,WA,ANDPINKALUMINUMOXIDEAL2O3,PA,WERESELECTEDANDSTUDIEDTHREENUMERICALVALUESOFEACHFACTORWEREDETERMINEDBASEDONTHEPRESTUDYRESULTSTHEL18ORTHOGONALARRAYWASSELECTEDTOCONDUCTTHEMATRIXEXPERIMENTFORFOUR3LEVELFACTORSOFTHESPHERICALGRINDINGPROCESS32DEFINITIONOFTHEDATAANALYSISENGINEERINGDESIGNPROBLEMSCANBEDIVIDEDINTOSMALLERTHEBETTERTYPES,NOMINALTHEBESTTYPES,LARGERTHEBETTERTYPES,SIGNEDTARGETTYPES,AMONGOTHERS8THESIGNALTONOISES/NRATIOISUSEDASTHEOBJECTIVEFUNCTIONFOROPTIMIZINGAPRODUCTORPROCESSDESIGNTHESURFACEROUGHNESSVALUEOFTHEGROUNDSURFACEVIAANADEQUATECOMBINATIONOFGRINDINGPARAMETERSSHOULDBESMALLERTHANTHATOFTHEORIGINALSURFACECONSEQUENTLY,THESPHERICALGRINDINGPROCESSISANEXAMPLEOFASMALLERTHEBETTERTYPEPROBLEMTHES/NRATIO,Η,ISDEFINEDBYTHEFOLLOWINGEQUATION8Η?10LOG10MEANSQUAREQUALITYCHARACTERISTIC?10LOG10?1NN?I1Y2I?1WHEREYIOBSERVATIONSOFTHEQUALITYCHARACTERISTICUNDERDIFFERENTNOISECONDITIONSNNUMBEROFEXPERIMENTAFTERTHES/NRATIOFROMTHEEXPERIMENTALDATAOFEACHL18ORTHOGONALARRAYISCALCULATED,THEMAINEFFECTOFEACHFACTORWASDETERMINEDBYUSINGANANALYSISOFVARIANCEANOVATECHNIQUEANDANFRATIOTEST8THEOPTIMIZATIONSTRATEGYOFTHE

簡介：1DEVELOPMENTANDANALYSISOFTHELARGESPANFRPWOVENWEBSTRUCTUREABSTRACTANINNOVATIVELARGESPANSTRUCTURALSYSTEM,NAMELYTHEFRPWOVENWEBSTRUCTUREFRPWWS,ISINTRODUCEDINTHISPAPERINANFRPWWS,THEHIGHSTRENGTHFRPSTRIPSARE“WOVEN”LIKEBAMBOOSTRIPSINACHINESEBAMBOOMATTOFORMAPLANEWEBTHEOUTEREDGEOFTHEWEBISANCHOREDONANOUTERRINGBEAM,ANDANINNERRINGBEAMISPROVIDEDTOANCHORTHEFRPSTRIPSATTHECENTEROFTHEWEBTHESTIFFNESSOFTHEWEBTORESISTVARIOUSLOADSISDERIVEDFROMTHEINITIALPRESTRESSINGDURINGTHE“WEAVING”STAGEANDTHEADDITIONALTENSIONINGASARESULTOFTHEOUTOFPLANEMOVEMENTOFTHEINNERRINGBEAMASARESULTOFTHEHIGHSTRENGTHTOWEIGHTRATIOOFFRP,THISNEWSTRUCTURALFORMOFFERSANATTRACTIVEOPTIONFORTHECONSTRUCTIONOFSPATIALSTRUCTURESWITHSPANSLONGERTHANAREPOSSIBLEWITHCONVENTIONALSTRUCTURALMATERIALSINTHISPAPER,THEBASICLAYOUTANDCONSTRUCTIONPROCEDUREFORASIMPLEFRPWWSISFIRSTPRESENTEDTHREEBASICWEAVINGPATTERNSARENEXTEXPLAINEDSEVERALVARIATIONSOFTHEBASICSTRUCTURALSYSTEMAREALSOPROPOSEDASIMPLEMECHANICALMODELISPRESENTEDFORTHEDEFORMATIONOFINDIVIDUALFRPSTRIPSRESULTSFROMAFINITEELEMENTANALYSISOFANEXAMPLESTRUCTUREAREALSOGIVENTHERESULTSOFTHESEANALYSESCONFIRMTHEFEASIBILITYOFTHEFRPWWS1INTRODUCTIONFRPISANEWKINDOFSTRUCTURALMATERIAL,WHOSEUSEINCIVILENGINEERINGHASBEENACTIVELYEXPLOREDINRECENTYEARSDUETOITSFAVORABLEPROPERTIESLIKE3TENSIONISUTILIZEDTORESISTLOADSHOWEVER,THEFRPWWSHASITSUNIQUEADVANTAGES1THEFRPSTRIPSAREIDEALFORSUPERLARGESPANSTRUCTURESDUETOTHEIRLOWSELFWEIGHTANDTHEIRSUPERIORMATERIALPROPERTIESINTHELENGTHWISEDIRECTION,WHICHAREEFFICIENTLYUTILIZED,WHILETHEWEAKNESSOFINFERIORPROPERTIESINTHETRANSVERSEDIRECTIONSISNOTEXPOSED2SIGNIFICANTDAMPINGCANBEEXPECTEDTOARISEFROMFRICTIONATJOINTSBETWEENFRPSTRIPS,WHICHCANENHANCETHERESISTANCEOFTHESTRUCTURETOWINDANDEARTHQUAKELOADS3THEREGULARWEAVINGPATTERNLEADSTOANAESTHETICALLYPLEASINGSURFACEAND4THECORROSIONRESISTANCEOFFRPANDTHEEASEOFINSTALLATIONBECAUSEOFITSLIGHTWEIGHTTRANSLATEINTOLOWMAINTENANCECOSTSINTHISPAPER,THEBASICLAYOUTANDCONSTRUCTIONPROCEDUREFORASIMPLEFRPWWSSYSTEMISPRESENTEDINDETAILTHEWEAVINGPATTERNSINPLANEARESUMMARIZEDINTOTHREETYPESSOMESPATIALFRPWWSFORMSFORPRACTICALAPPLICATIONSAREALSOPROPOSEDASIMPLEMECHANICALMODELFORINDIVIDUALFRPSTRIPSINTHEWEBISPRESENTEDRESULTSFROMTHEFINITEELEMENTANALYSISOFASIMPLEFRPWWSAREALSODESCRIBED2LAYOUTOFASIMPLEFRPWWSASIMPLEFRPWOVENWEBSTRUCTUREISCOMPOSEDOFAFRPWOVENWEB,ANOUTERRINGBEAMANDANINNERRINGBEAMFORANCHORAGE,ANDANADDITIONALWEIGHTORASETOFPRESTRESSEDTENDONS,ASSHOWNINFIGURE1THEWEBISWOVENWITHFRPSTRIPS,ANDCFRPSTRIPSOROTHERHIGHPERFORMANCEHYBRIDFRPSTRIPSARESUGGESTEDCFRPSTRIPS,WHICHHAVEBEEN

簡介：SHIFTDYNAMICSANDCONTROLOFDUALCLUTCHTRANSMISSIONSMANISHKULKARNI,TAEHYUNSHIM,YIZHANGDEPARTMENTOFMECHANICALENGINEERING,UNIVERSITYOFMICHIGANDEARBORN,DEARBORNMI48128,UNITEDSTATESRECEIVED4OCTOBER2005ACCEPTED1MARCH2006AVAILABLEONLINE18MAY2006ABSTRACTSHIFTSINADUALCLUTCHTRANSMISSIONDCTAREREALIZEDBYTORQUETRANSFERFROMONECLUTCHTOANOTHERWITHOUTTRACTIONINTERRUPTIONDUETOTHECONTROLLEDSLIPPAGEOFTHECLUTCHESTHETIMINGOFENGAGEMENTANDDISENGAGEMENTOFTHETWOCLUTCHESISCRITICALFORACHIEVINGASMOOTHSHIFTWITHOUTENGINEFLAREANDCLUTCHTIEUPTHISPAPERPRESENTSANANALYTICALMODELFORTHESIMULATION,ANALYSISANDCONTROLOFSHIFTDYNAMICSFORDCTVEHICLESADYNAMICMODELANDTHECONTROLLOGICFORTHEINTEGRATEDVEHICLEHAVEBEENDEVELOPEDUSINGMATLAB/SIMULINKASTHESIMULATIONPLATFORMTHEMODELHASBEENUSEDTOSTUDYTHEVARIATIONINOUTPUTTORQUEINRESPONSETODIFFERENTCLUTCHPRESSUREPROFILESDURINGSHIFTSOPTIMIZEDCLUTCHPRESSUREPROFILESHAVEBEENCREATEDFORTHEBESTPOSSIBLESHIFTQUALITYBASEDONMODELSIMULATIONASANUMERICALEXAMPLE,THEMODELISUSEDFORADCTVEHICLETOSIMULATETHEWIDEOPENTHROTTLEPERFORMANCEVEHICLELAUNCHANDSHIFTPROCESSAREBOTHSIMULATEDTOASSESSTRANSMISSIONSHIFTQUALITYANDVALIDATETHEEFFECTIVENESSOFTHESHIFTCONTROL?2006ELSEVIERLTDALLRIGHTSRESERVEDKEYWORDSDUALCLUTCHTRANSMISSIONAUTOMATICTRANSMISSIONS1INTRODUCTIONTHEREHASBEENACLEARTRENDINTHEAUTOMOTIVEINDUSTRYINRECENTYEARSTOWARDSINCREASEDRIDECOMFORTANDFUELEFFICIENCYASTHEPOWERTRANSMISSIONUNIT,TRANSMISSIONSPLAYANIMPORTANTROLEINVEHICLEPERFORMANCEANDFUELECONOMYTHEREARECURRENTLYSEVERALTYPESOFTRANSMISSIONSANDTHEASSOCIATEDTECHNOLOGIESTHATOFFERDIFFERENTPERFORMANCEPRIORITIESWHENFITINTOAVEHICLE1MANUALTRANSMISSIONSHAVEANOVERALLEFFICIENCYOF962,WHICHISTHEHIGHESTEFFICIENCYVALUEFORANYTYPEOFTRANSMISSIONCURRENTPRODUCTIONAUTOMATICSHAVEBEENIMPROVEDTOPROVIDEANEFFICIENCYOFNOTMORETHAN863BELTTYPECVT’SHAVEANOVERALLEFFICIENCYOF846,HOWEVER,THEMAJORADVANTAGEOFCVTISTHATITALLOWSTHEENGINETOOPERATEINTHEMOSTFUELEFFICIENTMANNER2AUTOMATEDMANUALTRANSMISSIONSHAVETHESAMEEFFICIENCYOFMANUALTRANSMISSIONSANDOFFEROPERATIONCONVENIENCESIMILARTOCONVENTIONALAUTOMATICTRANSMISSIONSTHEREEXISTTWOTECHNICALLYFEASIBLEDESIGNSFORAUTOMATEDLAYSHAFTGEARINGTRANSMISSIONSONEUSESASINGLECLUTCHANDISBASICALLYAMANUALTRANSMISSIONWITHANADDEDONCONTROLUNITTHATAUTOMATESTHECLUTCHANDSHIFTOPERATIONSINTHISDESIGN,THEREISANINTERRUPTIONOF0094114X/SEEFRONTMATTER?2006ELSEVIERLTDALLRIGHTSRESERVEDDOI101016/JMECHMACHTHEORY200603002CORRESPONDINGAUTHORTEL13135935539EMAILADDRESSANDINGUMICHEDUYZHANGMECHANISMANDMACHINETHEORY422007168–182WWWELSEVIERCOM/LOCATE/MECHMTMECHANISMANDMACHINETHEORYTHEENGINEOUTPUTTORQUEISINTERPOLATEDINTERMSOFTHETHROTTLEANGLEANDRPMFROMTHEENGINEMAPGEARSHAVENOBACKLASHALLTHEMECHANICALLOSSESAREMODELEDASAPARTOFTHEVEHICLEDRAGDELAYSDUETOHYDRAULICACTUATIONSYSTEMARENOTCONSIDEREDCLUTCHESAREMODELEDASCOULOMBFRICTIONELEMENTSTEMPERATUREEFFECTSOFTHEDRIVETRAINARENEGLECTEDCL2CL1SYN5RSYN6SYN13SYN244231INPUTSHAFTOUTPUT6R5FINALDRIVEPINION2FINALDRIVEPINION1INTERMEDIATESHAFT1INTERMEDIATESHAFT2SYN5RSYN6SYN13SYN24INPUTSHAFTOUTPUT6R5SYN5RSYN6SYN13SYN24INPUTSHAFTOUTPUT6R5FINALDRIVEPINION2FINALDRIVEPINION1INTERMEDIATESHAFT1INTERMEDIATESHAFT2FIG1DCTSTICKDIAGRAM4OUTPUTSHAFT4RCL1CL2131265INPUTSHAFTII/PIECL1312ENGINEKMCMIMEΩPI/ΩK1C1IHISI1SΩI2IMΩIMΩHΩK2C2I3AIOΩWΩFIG2DCTDYNAMICMODEL170MKULKARNIETAL/MECHANISMANDMACHINETHEORY422007168–182

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簡介：中文中文62586258字外文文獻外文文獻RURALANDURBANLANDDEVELOPMENTANDLANDTENURESYSTEMSACOMPARISONBETWEENSOUTHAFRICAANDBOTSWANASUSANBOUILLONLEGALADVISORCITYCOUNCILOFPRETORIAINTRODUCTIONFRANKLINDROOSEVELTONCESAIDTHAT‘EVERYPERSONWHOINVESTSINLANDNEARAGROWINGCITY,ADOPTSTHESURESTANDSAFESTMETHODOFBECOMINGINDEPENDENT,FORLANDISTHEBASISOFWEALTH’THEPURPOSEOFTHISPAPERISTODISCUSSTHERURALANDURBANLANDDEVELOPMENTANDLANDTENURESYSTEMSOFSOUTHAFRICAANDBOTSWANA,ANDTOEXPLAINTHEIRCONTRIBUTIONSTOURBANSUSTAINABILITYDEVELOPMENTPLANNINGINBOTSWANABOTSWANAISLOCATEDATTHECENTREOFTHESOUTHAFRICANPLATEAU,ANDISBORDEREDBYSOUTHAFRICAONTHESOUTHANDSOUTHEAST,ZIMBABWEONTHENORTHEASTANDNAMIBIAONTHEWESTANDNORTHWESTAPPROXIMATELY23OFTHEPOPULATIONISINURBANAREASAND77INRURALAREASBOTSWANAHASARICHTRIBALCULTURE,ANDTHEREFOREITISNOTSURPRISINGTHATTHEBOTSWANALEGALSYSTEMCONSISTSOFLOCALTRIBALCOURTS,WHICHADJUDICATETRADITIONALMATTERSANDTRIBALLANDBOARDS,WHICHRULEONLANDUSEMATTERSINTRIBALLANDSANDTRADITIONALVILLAGESTOWNCOUNCILSRULEONLANDUSEMATTERSINURBANAREASTHEGOVERNMENTOFBOTSWANAHASADOPTEDASYSTEMOFDEVELOPMENTPLANNINGWHICHHASCOPEDRELATIVELYWELLCOMPAREDWITHOTHERAFRICANCOUNTRIESDEVELOPMENTPLANNINGINVOLVESTHEPREPARATIONOFLANDUSEPLANSFORBOTHURBANANDRURALAREASTHEPRACTICEINBOTSWANAISTHATTHEPUBLICISMADEAWAREOFTHEIMPLICATIONSOFLANDUSEPLANSBEFORELANDISZONEDFORVARIOUSUSESPUBLICAWARENESSANDPARTICIPATIONISOFBOTSWANAISENTITLEDTOAPPLYFORTHESERIGHTSLANDBOARDSMAINTAINTHEIROWNRECORDORREGISTRATIONSYSTEMANDRIGHTSARENOTREGISTEREDINTHECENTRALDEEDSREGISTRATIONSYSTEMOFBOTSWANA,APPARENTLYTOKEEPTHEMMOREAFFORDABLETHELANDBOARDSAREENTITLEDTOISSUECERTIFICATESOFCUSTOMARYGRANTSORCERTIFICATESOFOCCUPATIONPROVISIONHASBEENMADEFORTHECONVERSIONOFTHESECERTIFICATESINTOTITLESREGISTRABLEINTHEDEEDSREGISTRYONCEDEMANDARISESTODEALWITHTHESECERTIFICATESINTHECOMMERCIALLENDINGMARKETANYCHANGEINRIGHTHOLDERMUSTBEREPORTEDTOTHELANDBOARDINORDERTOMAINTAINTHEACCURACYOFTHERECORDSYSTEMOFTHELANDBOARDSHELTERPROVISIONINRURALAREASHASBEENONINDIVIDUALSINITIATIVESTHEMOSTIMPORTANTPREREQUISITEFORHOUSINGDEVELOPMENT,WHICHISACCESSTOLAND,HASNOTREALLYBEENADISTURBINGISSUEDUETOTHEFACTTHATALLMALEANDFEMALECITIZENSAREALLOCATEDTRIBALLANDFORFREE,BUTINANEFFORTTOFACILITATESHELTERPROVISIONINRURALAREAS,THEGOVERNMENTINTENDSTOINTRODUCEARURALHOUSINGPROGRAMMELANDUSEPLANNINGISNOTANEWPHENOMENONINBOTSWANAPASTEXPERIENCESANDRECORDSINDICATETHATTHETRADITIONALCHIEFSWHOHADAUTHORITYONLANDHAVEALWAYSDONESOMEFORMOFLANDUSEPLANNINGFORMALLANDUSEPLANNINGINBOTSWANASTARTEDWITHTHEIMPLEMENTATIONOFTHETRIBALGRAZINGLANDPOLICYIN1975,WHENSOMEAREASWEREZONEDFORWILDLIFEUSE,OTHERSBECAMERESERVEDAREAS,WHILEOTHERAREASCONTINUEDTOBEFORCOMMUNALUSETHISPOLICYENABLEDINDIVIDUALSORGROUPSTOHAVEEXCLUSIVEUSEOFLANDINAREASZONEDFORSUCHUSETHESERIGHTSAREPERMANENT,EXCLUSIONARYANDINHERITABLETHEYMAYONLYBEREVOKEDBYTHELANDBOARDINCIRCUMSTANCESWHERETHERIGHTHOLDERFAILSTOUTILIZETHELANDONTERMSSPECIFIEDBYTHELANDBOARD,ORFAILSTODEVELOPTHELANDACCORDINGTOTHESPECIFIEDPURPOSESWITHINFIVEYEARSORWHERETHELANDWASNOTDISTRIBUTEDFAIRLYINTHESEINSTANCES,THELANDDOESNOTREVERTTOTHEGOVERNMENTBUTISREALLOCATEDBYTHELANDBOARDTOOTHERAPPLICANTSTHISPOLICYWASTHEREFOREAMAJORPROGRAMMETHROUGHWHICHRURALDEVELOPMENTWASTOBEACHIEVEDTHEDISTRICTSUPTONOWCONTINUETOPREPAREANDUPDATETHEIRRESPECTIVEINTEGRATEDLANDUSEPLANSINTHEPREPARATIONOFSUCHPLANSTHECOMMUNITIESHAVEMAJORINPUTS

簡介：ANUMERICALANALYSISOFTHEINTERACTIONBETWEENTHEPISTONOILFILMANDTHECOMPONENTDEFORMATIONINARECIPROCATINGCOMPRESSORJRCHO,SJMOONSCHOOLOFMECHANICALENGINEERING,PUSANNATIONALUNIVERSITY,JANGJEONDONG,KUMJUNGKU,BUSAN609735,SOUTHKOREARECEIVED27DECEMBER2003RECEIVEDINREVISEDFORM10MAY2004ACCEPTED6OCTOBER2004AVAILABLEONLINE23NOVEMBER2004ABSTRACTTHEPISTONSECONDARYMOTIONSIGNIFICANTLYINFLUENCESTHEMAJORCHARACTERISTICSOFLUBRICATIONINARECIPROCATINGCOMPRESSOR,SUCHASTHEOILLEAKAGE,THEPISTONSLAPPHENOMENONANDTHEFRICTIONALPOWERLOSSTHEREFORE,THEDESIGNPARAMETERSGOVERNINGPISTONDYNAMICSSHOULDBECAREFULLYDETERMINEDBASEDUPONARELIABLEDYNAMICCHARACTERISTICINVESTIGATIONASAPRELIMINARYRESEARCHSTEP,THISPAPERISCONCERNEDWITHTHEFINITEELEMENTANALYSISFORTHEPISTONDYNAMICRESPONSEBYCOUPLINGFDMFORTHELUBRICATINGPRESSUREFIELDWITHFEMFORTHEPISTONDYNAMICMOTION,WENUMERICALLYAPPROXIMATETHELUBRICANT–STRUCTUREINTERACTIONINARECIPROCATINGCOMPRESSORNUMERICALRESULTSILLUSTRATINGTHETHEORETICALWORKAREPRESENTEDQ2004ELSEVIERLTDALLRIGHTSRESERVEDKEYWORDSRINGLESSSMALLRECIPROCATINGCOMPRESSORLUBRICANT–STRUCTUREINTERACTIONPISTONSECONDARYMOTIONECCENTRICITYANDTILTFEMANDFDM1INTRODUCTIONRINGLESSSMALLRECIPROCATINGCOMPRESSORSAREWIDELYUSEDTOCOMPRESSCOOLANTGASINHOUSEHOLDREFRIGERATORSANDAIRCONDITIONERSINSUCHDEVICESTHEPISTONBECOMESAKEYCOMPONENTINFLUENCINGALLTHEMAJORPERFORMANCESOFRECIPROCATINGCOMPRESSOR,SUCHASPUMPINGEFFICIENCY,NOISE,POWERCONSUMPTION,ANTIWEAR,ANDSOONITISBECAUSEPISTONDYNAMICSCHARACTERIZESTHEOILLEAKAGE,THEPISTONSLAPPHENOMENON1ANDTHEFRICTIONALLOSS,WHICHDETERMINESUCHMAJORPERFORMANCESWHILEMOVINGUPANDDOWNALONGTHELUBRICATEDCYLINDERWALL,APISTONDISPLAYSOSCILLATORYRADIALTRANSLATIONANDROTATIONWITHINTHEOILFILMCLEARANCEOWINGTOTHEUNBALANCEINDYNAMICFORCESACTINGONITTHISSECONDARYMOTIONINPISTONDYNAMICSHASBECOMEACRUCIALRESEARCHSUBJECTINORDERTOIMPROVETHEPERFORMANCEANDSTABILITYOFRECIPROCATINGCOMPRESSOR2,3THEPISTONSECONDARYMOTIONISASSOCIATEDWITHSEVERALDESIGNPARAMETERS,SUCHASTHERADIALCLEARANCE,THELUBRICANTVISCOSITY,THEWRISTPINLOCATION,THECRANKSHAFTECCENTRICITY,ANDTHEPISTONSKIRTPROFILE4,5ASWELL,APISTONINRINGLESSRECIPROCATINGCOMPRESSORSISSUBJECTTOLUBRICATINGPRESSUREANDFRICTIONALFORCE,BESIDESTHEPRIMARYCOOLANTPRESSUREANDTHEMOTORDRIVENFORCESO,THEPISTONDYNAMICMOTIONISSTRONGLYINFLUENCEDBYTHEGEOMETRICSTRUCTUREANDTHEOILFILMPRESSURETHEREFORE,THEABOVEMENTIONEDDESIGNPARAMETERSSHOULDBECAREFULLYDETERMINED,INORDERTOMAXIMIZETHEDYNAMICPERFORMANCEANDSTABILITY,BASEDUPONAPARAMETRICDYNAMICINVESTIGATION,WHICHWOULDBEACHIEVEDBYANAPPROPRIATECOUPLEDNUMERICALANALYSIS,SUCHASONEFORGENERALFLUID–STRUCTUREINTERACTIONPROBLEMS6,7ACCORDINGTOOURBRIEFLITERATURESURVEY,LIETAL8INVESTIGATEDTHELUBRICATIONCHARACTERISTICSTHEORETICALLYANDEXPERIMENTALLY,ANDFOUNDTHEEFFECTOFTHEWRISTPINLOCATIONONTHEFRICTIONALFORCETRADITIONALLY,THELUBRICATINGPRESSUREHASBEENMODELEDBYREYNOLDSEQUATIONBYASSUMINGTHEOILLUBRICANTBEANEWTONIANISOVISCOUSFLUIDONTHEOTHERHAND,THEPISTONDYNAMICSHASBEENMOSTLYDESCRIBEDBYTHEPARTICLEDYNAMICSEQUATIONSFORTHEPISTONMASSCENTERBYREPLACINGEXTERNALSURFACETRACTIONSWITHEQUIVALENTRESULTANTFORCESANDMOMENTS9–11FURTHERMORE,BOTHPISTONANDCYLINDERWEREASSUMEDASRIGIDBODIESEVENTHOUGHTHISPARTICLEDYNAMICSAPPROACHMAKESTHEPROBLEMSIMPLERANDREDUCESTHECOMPUTATIONTIME,0301679X/SEEFRONTMATTERQ2004ELSEVIERLTDALLRIGHTSRESERVEDDOI101016/JTRIBOINT200410002TRIBOLOGYINTERNATIONAL382005459–468WWWELSEVIERCOM/LOCATE/TRIBOINTCORRESPONDINGAUTHORTELC82515102467FAXC82515147640EMAILADDRESSJRCHOHYOWONPUSANACKRJRCHOONTHEOTHERHAND,B0INDICATESTHEINCLINEDANGLEOFTHECONNECTINGRODFORCETOTHEVERTICALAXISOWINGTOTHEPISTONECCENTRICITYINTHEXDIRECTIONWENOTETHATTHEEFFECTOFTHEPISTONTILTABOUTTHEWRISTPINISNEGLECTEDTHEN,THECONNECTINGRODFORCECOMPONENTSANDTHEINCLINEDANGLEAREDETERMINEDASFYDFTZMPAPCPR2DPGKPATCFPF4FXDFTZFPX5B0ZTANK1DFXFYT6WHEREMPDENOTESTHETOTALPISTONMASS3DISPLACEMENTANDLUBRICATINGPRESSUREFIELDSLETUXTBETHEDISPLACEMENTFIELDOFTHEPISTONANDCYLINDER,THESTRUCTURALDYNAMICRESPONSEISGOVERNEDBYSIJDUTJCFIZR€UI7WITHINITIALANDBOUNDARYCONDITIONSUIDX0TZ08UIDXTTZ0SIJNJZTI9WHERERDENOTESTHEMASSDENSITYOFTHESTRUCTURALCOMPONENTSANDTITHETRACTIONCOMPONENTSBYTHECOOLANTGASANDLUBRICATINGOILPRESSURESINORDERTODESCRIBETHELUBRICATINGPRESSUREFIELDWITHINTHERADIALCLEARANCE,WEINTRODUCEACYLINDRICALCOORDINATEATTACHEDTOTHECENTEROFTHEPISTONTOPSURFACE,ASDEPICTEDINFIG3THEYAXISDIRECTSTOTHESAMEDIRECTIONASONEINTHEPREVIOUSFIXEDCARTESIANCOORDINATESYSTEMREFERRINGTOFIG1B,THEPISTONISALLOWEDTOMOVEONLYINTHEXDIRECTIONANDTOTILTABOUTTHEWRISTPINAXISTHEPISTONAXISECCENTRICITYISDENOTEDBYEWHILETHETILTINGANGLEBYGWEASSUMETHATTHEOILFILMISALWAYS100FULLWITHINTHERADIALCLEARANCEOVERWHOLE3608ANDAXIALLENGTHOFTHEPISTONTHELUBRICATINGOILFLOWISASSUMEDTOBEINCOMPRESSIBLELAMINARBECAUSETWOCHARACTERISTICLENGTHSHANDRARESIGNIFICANTLYLARGERTHANTHEFLOWTHICKNESSAND,THEPRESSUREVARIATIONINTHERDIRECTIONISIGNOREDBECAUSETHERADIALCLEARANCEISMUCHSMALLERTHANTHEPISTONRADIUSBYNEGLECTINGTHEBODYANDINERTIAFORCESOFLUBRICATINGOIL,THELUBRICATINGPRESSUREFIELDPY,QISGOVERNEDBYREYNOLDS’SEQUATIONWHICHISBASEDUPONTHEINCOMPRESSIBLENAVIER–STOKESEQUATIONSANDTHECONTINUITYCONDITIONVVYH3VPVY??CVR2VQH3VPVQ??Z6VPMVHVY10EQUIPPEDWITHTHEBOUNDARYCONDITIONSGIVENBYPZPGATYZ0PZPAATYZH11VPVQZ0ATQZ0ANDP12WHEREMREFERSTOTHEOILVISCOSITYBYDENOTINGYWBETHEWRISTPINLOCATION,THEACTUALOILTHICKNESSHISEXPRESSEDBYHDYQTZCK?ECDYWKYTG?COSQ13REFERRINGTOTHESIGNCONVENTIONFORFORCESSHOWNINFIG2,TWORESULTANTFORCESFPXANDFPFARECALCULATEDSUCHTHATFPXZDH0D2P0PDYQTCOSQRDQDY14FPFZDH0D2P0MVPHCH2VPVY??RDQDY15ONTHEOTHERHAND,THEINSTANTANEOUSVOLUMETRICOILLEAKAGEQFFTHROUGHOUTTHERADIALCLEARANCEISCALCULATEDBYQFDFTZD2P0HVP2KH312MVPVY??YZHRDQ16AND,THECYCLEAVERAGEDPOWERCONSUMPTIONPISCALCULATEDACCORDINGTOPZ12PD2P0PFDFTDF17FIG3LUBRICATIONWITHINTHERADIALCLEARANCEBETWEENPISTONANDCYLINDERFIG2FREEBODYDIAGRAMOFTHEPISTONJRCHO,SJMOON/TRIBOLOGYINTERNATIONAL382005459–468461

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簡介：JM弗米利耶，CH肖爾茨/構造地質學雜志21（1999）16231636中文中文9800字從小斷層的顯微構造研究斷層的延伸和分離米弗米利耶，克里斯托福肖爾茨美國,紐約州10964號，哥倫比亞大學，寶馬山花園，拉蒙特多赫蒂地球天文臺1997122收稿1999512接受摘要自然形成的斷層通常是斷開的。對紐約阿爾斯特縣雄格姆山一個小脆性斷層微觀構造的詳細研究提供了研究斷層分離過程新的理解。在脆性斷層中斷層的延伸方向可由斷層作用范圍內形成的微裂隙的方位來確定。我們已經確定沿走滑斷層若干部分斷層延伸的方向，這些方向指示了從分離中心到邊緣個別部分斷層的發(fā)育。這一信息，與已發(fā)現(xiàn)的斷層幾何形態(tài)相結合，可以讓我們重建一個近乎合理的分離斷層和分離邊界的發(fā)育史。ELSEVIER科技有限公司保留所有版權。1引言引言對斷層易碎部分的觀察揭示了它們是很復雜的系統(tǒng)，其中包括顯示不同連通程度部分（如西格爾和波拉德，1980,1983；馬特爾等，1988；皮科克，1991皮科克和桑德森，1991,1994；安德斯和SCHLISCHE，1994年TRUDGILL和卡特賴特，1994；卡特賴特等，1995；DAWERS和安德斯，1995）。雖然分離斷塊間應力的相互作用已經模擬出來了（如西格爾和波拉德，1980；伯格曼和波拉德，1994；伯格曼等，1994）并且在這一區(qū)域各部分邊界已經被研究了（馬特爾等，1988年；安德斯和SCHLISCHE，1994；卡特賴特等，1995；哈金斯等，1995）但是對各部分形成的過程還沒有很好的認識。斷層的分離部分觀察到的分離的幾何形態(tài)可能是先存的分離部分或先存較大構造的破裂造成的。斷層生長產生兩個變形區(qū)由斷層面和磨碎的巖石組成的斷層核部，以及被稱為破碎帶凱恩等，1996大量廣泛分布的變形區(qū)。這兩個變形區(qū)紀錄了補充斷層發(fā)育的證據(jù)。結合對變形帶和部分邊界的幾何形態(tài)的觀察可以重建斷層各部分形成的方式。斷層發(fā)育的研究通常利用到剪切裂隙來模擬斷層（如西格爾和波拉德，1980；科維和肖爾茨，1992；肖爾茨等，1993）。雖然裂隙（理想化彈性不連續(xù)的）與斷層區(qū)別顯著（巖石構造的不連續(xù)，平行于不連續(xù)區(qū)的位移）但應力與剪切裂縫和斷層相關領域類似（恩格爾德等，1993）。自然界斷層發(fā)育的實際模式必須區(qū)別于實驗室的觀察，因斷層不像裂隙，它不是簡單的沿破裂面延伸，而是由一個更為復雜的破JM弗米利耶，CH肖爾茨/構造地質學雜志21（1999）16231636INGRAFFEA，1987；里奇斯舒和洛克納，1994；弗米利耶和肖爾茨，1998）。過程區(qū)微裂隙形成于斷端線周圍的巖石中，并且隨著斷層的生長在其延伸前端處于活動狀態(tài)。其結果產生了圍繞斷層核心的連續(xù)過程區(qū)（弗米利耶和肖爾茨，1998）。由于開放模式微裂隙在長度方向的生長平行于最大壓應力的方向Δ1，擴張方向平行于最小壓應力Δ3，它們的方位是當?shù)刂鲬Ψ较虻闹匾甘?。因此，過程區(qū)內微裂隙的方位代表裂隙尖端應力場的通道（弗米利耶和肖爾茨，1998）。由斷層延伸引起的本地應力場的改變可能導致過程區(qū)微裂隙不對稱分布（肖爾茨等，1993；安德斯和維爾奇科，1994；摩爾和洛克納，1995；弗米利耶和肖爾茨，1998）。對于模式II（滑動，剪切位移）遠部最大壓應力在裂隙尖端附近旋轉以使其與斷裂面在壓縮象限夾角變小，在拉伸象限夾角變大（圖1）。這樣產生了不對稱應力貫穿整個裂隙面。這種不對稱感不僅依賴于滑移的感覺，而且也取決于裂隙從尖端到觀察點延伸的方向。對于右旋位移，從延伸的方向看，主應力及相關微裂隙最大聚合處會在裂隙右手側旋轉至較大角度，在裂隙左手側旋轉至較小角度。圖1所示應力的方向肖爾茨等（1993年）已計算出來，他們利用了科維和肖爾茨的斷層發(fā)育模型的壓力極限原理（科維和肖爾茨，1992），裂隙尖端應力場附近彈性解（如勞恩和威爾肖，1975），及實證擴容壓力功能（肖爾茨，1968）。提出的假設是裂隙會出現(xiàn)在應力超過臨界擴容壓力的所有點上。累計微裂隙密度，代表垂直斷層任意給定距離的斷端線的通道，它是通過融合平行于斷層的那個距離上整個斷端線應力場來估計的，并乘以經驗擴容壓力函數(shù)的最大壓力值。這些計算值預示微裂隙密度成對數(shù)遞減，作為與斷層面垂直距離的函數(shù)。應力方向的不對稱性是伴隨著最小壓應力值的不對稱及拉應力象限較高拉應力。這種不對稱微裂隙被稱為模式II鮮明特點，它們也能確定模式II斷層的眼神方向（弗米利耶和肖爾茨，1998）。雖然模式II裂隙延伸應力場的方向在整個裂隙面內不對稱，但模式I和模式III裂隙的應力方向是對稱的。因此，不能通過微裂隙方位的觀察簡單確定這些模式延伸的方向。對于所有模式周圍的遠程壓力在裂隙尖端被大大擴大了，這些高應力尖端的通道預計可產生過程區(qū)，過程區(qū)在斷層延伸后仍處于活躍狀態(tài)（波拉德和西格爾，1987；弗米利耶和肖爾茨，1998）。巖石可能經受的最高應力會在斷層前端附近，恰好先于斷層；應力集中產生的破壞可能超過斷層上隨后滑落產生的破壞，以上兩個預測都是合理的。實驗室中實驗的斷層發(fā)育已經產生了這種活躍的過程區(qū)，并用聲發(fā)射原理確認預測的延伸方向（洛克納等，1992；里奇斯舒和洛克納，1994年；摩爾和洛克納，1995）。隨著剪切面上滑移的增加，可形成一層由細粒斷層泥或碎裂巖組成的巖石。斷層巖芯（凱恩等，1996）由斷層面上的滑移磨碎形成的碎屑累積組成。由于斷層泥區(qū)的厚度通常隨著斷層位移的增加而增加（肖爾茨，1987；赫爾，1988），通過對比，我們可以推測隨著滑移從末端到斷層中心的增加其核心的厚度也增加。如果是這種情況，厚度最大的核心位置可能指示滑移的起始位置。這提供了免費的信息，可用于驗證由過程區(qū)研究決定的延伸方向。這項研究提供了過程區(qū)及和分離的易碎斷層有關的斷層核心的觀察信息。過程

簡介：CHANGINGROLESOFTHECLIENTS,ARCHITECTSANDCONTRACTORSTHROUGHBIMRIZALSEBASTIANTNOBUILTENVIRONMENTANDGEOSCIENCES,DELFT,THENETHERLANDSABSTRACTPURPOSE–THISPAPERAIMSTOPRESENTAGENERALREVIEWOFTHEPRACTICALIMPLICATIONSOFBUILDINGINFORMATIONMODELLINGBIMBASEDONLITERATUREANDCASESTUDIESITSEEKSTOADDRESSTHENECESSITYFORAPPLYINGBIMANDREORGANISINGTHEPROCESSESANDROLESINHOSPITALBUILDINGPROJECTSTHISTYPEOFPROJECTISCOMPLEXDUETOCOMPLICATEDFUNCTIONALANDTECHNICALREQUIREMENTS,DECISIONMAKINGINVOLVINGALARGENUMBEROFSTAKEHOLDERS,ANDLONGTERMDEVELOPMENTPROCESSESDESIGN/METHODOLOGY/APPROACH–THROUGHDESKRESEARCHANDREFERRINGTOTHEONGOINGEUROPEANRESEARCHPROJECTINPRO,THEFRAMEWORKFORINTEGRATEDCOLLABORATIONANDTHEUSEOFBIMAREANALYSEDTHROUGHSEVERALREALCASES,THECHANGINGROLESOFCLIENTS,ARCHITECTS,ANDCONTRACTORSTHROUGHBIMAPPLICATIONAREINVESTIGATEDFINDINGS–ONEOFTHEMAINFINDINGSISTHEIDENTIFICATIONOFTHEMAINFACTORSFORASUCCESSFULCOLLABORATIONUSINGBIM,WHICHCANBERECOGNISEDAS“POWER”PRODUCTINFORMATIONSHARINGP,ORGANISATIONALROLESSYNERGYO,WORKPROCESSESCOORDINATIONW,ENVIRONMENTFORTEAMWORKE,ANDREFERENCEDATACONSOLIDATIONRFURTHERMORE,ITISALSOFOUNDTHATTHEIMPLEMENTATIONOFBIMINHOSPITALBUILDINGPROJECTSISSTILLLIMITEDDUETOCERTAINCOMMERCIALANDLEGALBARRIERS,ASWELLASTHEFACTTHATINTEGRATEDCOLLABORATIONHASNOTYETBEENEMBEDDEDINTHEREALESTATESTRATEGIESOFHEALTHCAREINSTITUTIONSORIGINALITY/VALUE–THISPAPERCONTRIBUTESTOTHEACTUALDISCUSSIONINSCIENCEANDPRACTICEONTHECHANGINGROLESANDPROCESSESTHATAREREQUIREDTODEVELOPANDOPERATESUSTAINABLEBUILDINGSWITHTHESUPPORTOFINTEGRATEDICTFRAMEWORKSANDTOOLSITPRESENTSTHESTATEOFTHEARTOFEUROPEANRESEARCHPROJECTSANDSOMEOFTHEFIRSTREALCASESOFBIMAPPLICATIONINHOSPITALBUILDINGPROJECTSKEYWORDSEUROPE,HOSPITALS,THENETHERLANDS,CONSTRUCTIONWORKS,RESPONSEFLEXIBILITY,PROJECTPLANNINGPAPERTYPEGENERALREVIEW1INTRODUCTIONHOSPITALBUILDINGPROJECTS,AREOFKEYIMPORTANCE,ANDINVOLVESIGNIFICANTINVESTMENT,ANDUSUALLYTAKEALONGTERMDEVELOPMENTPERIODHOSPITALBUILDINGPROJECTSAREALSOVERYCOMPLEXDUETOTHECOMPLICATEDREQUIREMENTSREGARDINGHYGIENE,SAFETY,SPECIALEQUIPMENTS,ANDHANDLINGOFALARGEAMOUNTOFDATATHEBUILDINGPROCESSISVERYDYNAMICANDCOMPRISESITERATIVEPHASESANDINTERMEDIATECHANGESMANYACTORSWITHSHIFTINGAGENDAS,ROLESANDRESPONSIBILITIESAREACTIVELYINVOLVED,SUCHASTHEHEALTHCAREINSTITUTIONS,NATIONALANDLOCALGOVERNMENTS,PROJECTDEVELOPERS,FINANCIALINSTITUTIONS,ARCHITECTS,CONTRACTORS,ADVISORS,FACILITYMANAGERS,ANDEQUIPMENTMANUFACTURERSANDSUPPLIERSSUCHBUILDINGPROJECTSAREVERYMUCHINFLUENCED,BYTHEHEALTHCAREPOLICY,WHICHCHANGESRAPIDLYINRESPONSETOTHEMEDICAL,SOCIETALANDTECHNOLOGICALDEVELOPMENTS,ANDVARIESGREATLYBETWEENCOUNTRIESWORLDHEALTHORGANIZATION,2000INTHENETHERLANDS,FOREXAMPLE,THEWAYABUILDINGPROJECTINTHETHECURRENTISSUEANDFULLTEXTARCHIVEOFTHISJOURNALISAVAILABLEATWWWEMERALDINSIGHTCOM/09699988HTMECAM18,2176RECEIVEDJANUARY2010ACCEPTEDFEBRUARY2010ENGINEERING,CONSTRUCTIONANDARCHITECTURALMANAGEMENTVOL18NO2,2011PP176187QEMERALDGROUPPUBLISHINGLIMITED09699988DOI101108/096999811111111482008,NEWLEGISLATIONONTHEMANAGEMENTOFHOSPITALBUILDINGPROJECTSANDREALESTATEHASCOMEINTOFORCEINTHISNEWLEGISLATION,APERMITFORHOSPITALBUILDINGPROJECTUNDERTHEWTZIISNOLONGEROBLIGATORY,NOROBTAINABLEDUTCHMINISTRYOFHEALTH,WELFAREANDSPORT,2008THISCHANGEALLOWSMOREFREEDOMFROMTHESTATEDIRECTEDPOLICY,ANDRESPECTIVELY,ALLOCATESMORERESPONSIBILITIESTOTHEHEALTHCAREORGANISATIONSTODEALWITHTHEFINANCINGANDMANAGEMENTOFTHEIRREALESTATETHENEWPOLICYIMPLIESTHATTHEHEALTHCAREINSTITUTIONSAREFULLYRESPONSIBLETOMANAGEANDFINANCETHEIRBUILDINGPROJECTSANDREALESTATETHEGOVERNMENT’SSUPPORTFORTHECOSTSOFHEALTHCAREFACILITIESWILLNOLONGERBEGIVENSEPARATELY,BUTWILLBEINCLUDEDINTHEFEEFORHEALTHCARESERVICESTHISMEANSTHATHEALTHCAREINSTITUTIONSMUSTEARNBACKTHEIRINVESTMENTONREALESTATETHROUGHTHEIRSERVICESTHISNEWPOLICYINTENDSTOSTIMULATESUSTAINABLEINNOVATIONSINTHEDESIGN,PROCUREMENTANDMANAGEMENTOFHEALTHCAREBUILDINGS,WHICHWILLCONTRIBUTETOEFFECTIVEANDEFFICIENTPRIMARYHEALTHCARESERVICESTHENEWSTRATEGYFORBUILDINGPROJECTSANDREALESTATEMANAGEMENTENDORSESANINTEGRATEDCOLLABORATIONAPPROACHINORDERTOASSURETHESUSTAINABILITYDURINGCONSTRUCTION,USE,ANDMAINTENANCE,THEENDUSERS,FACILITYMANAGERS,CONTRACTORSANDSPECIALISTCONTRACTORSNEEDTOBEINVOLVEDINTHEPLANNINGANDDESIGNPROCESSESTHEIMPLICATIONSOFTHENEWSTRATEGYAREREFLECTEDINTHECHANGINGROLESOFTHEBUILDINGACTORSANDINTHENEWPROCUREMENTMETHODINTHETRADITIONALPROCUREMENTMETHOD,THEDESIGN,ANDITSDETAILS,AREDEVELOPEDBYTHEARCHITECT,ANDDESIGNENGINEERSTHEN,THECLIENTTHEHEALTHCAREINSTITUTIONSENDSANAPPLICATIONTOTHEMINISTRYOFHEALTHTOOBTAINANAPPROVALONTHEBUILDINGPERMITANDTHEFINANCIALSUPPORTFROMTHEGOVERNMENTFOLLOWINGTHIS,ACONTRACTORISSELECTEDTHROUGHATENDERPROCESSTHATEMPHASISESTHESEARCHFORTHELOWESTPRICEBIDDERDURINGTHECONSTRUCTIONPERIOD,CHANGESOFTENTAKEPLACEDUETOCONSTRUCTABILITYPROBLEMSOFTHEDESIGNANDNEWREQUIREMENTSFROMTHECLIENTBECAUSEOFTHEHIGHLEVELOFTECHNICALCOMPLEXITY,ANDMOREOVER,DECISIONMAKINGCOMPLEXITIES,THEWHOLEPROCESSFROMINITIATIONUNTILDELIVERYOFAHOSPITALBUILDINGPROJECTCANTAKEUPTOTENYEARSTIMEAFTERTHEDELIVERY,THEHEALTHCAREINSTITUTIONISFULLYINCHARGEOFTHEOPERATIONOFTHEFACILITIESREDESIGNSANDCHANGESALSOTAKEPLACEINTHEUSEPHASETOCOPEWITHNEWFUNCTIONSANDDEVELOPMENTSINTHEMEDICALWORLDVANREEDTDORTLAND,2009THEINTEGRATEDPROCUREMENTPICTURESANEWCONTRACTUALRELATIONSHIPBETWEENTHEPARTIESINVOLVEDINABUILDINGPROJECTINSTEADOFARELATIONSHIPBETWEENTHECLIENTANDARCHITECTFORDESIGN,ANDTHECLIENTANDCONTRACTORFORCONSTRUCTION,INANINTEGRATEDPROCUREMENTTHECLIENTONLYHOLDSACONTRACTUALRELATIONSHIPWITHTHEMAINPARTYTHATISRESPONSIBLEFORBOTHDESIGNANDCONSTRUCTIONJOINTCONTRACTSTRIBUNAL,2007THETRADITIONALBORDERSBETWEENTASKSANDOCCUPATIONALGROUPSBECOMEBLURREDSINCEARCHITECTS,CONSULTINGFIRMS,CONTRACTORS,SUBCONTRACTORS,ANDSUPPLIERSALLSTANDONTHESUPPLYSIDEINTHEBUILDINGPROCESSWHILETHECLIENTONTHEDEMANDSIDESUCHCONFIGURATIONPUTSTHEARCHITECT,ENGINEERANDCONTRACTORINAVERYDIFFERENTPOSITIONTHATINFLUENCESNOTONLYTHEIRROLES,BUTALSOTHEIRRESPONSIBILITIES,TASKSANDCOMMUNICATIONWITHTHECLIENT,THEUSERS,THETEAMANDOTHERSTAKEHOLDERSTHETRANSITIONFROMTRADITIONALTOINTEGRATEDPROCUREMENTMETHODREQUIRESASHIFTOFMINDSETOFTHEPARTIESONBOTHTHEDEMANDANDSUPPLYSIDESITISESSENTIALFORTHECLIENTANDCONTRACTORTOHAVEAFAIRANDOPENCOLLABORATIONINWHICHBOTHCANOPTIMALLYUSETHEIRCOMPETENCIESTHEEFFECTIVENESSOFINTEGRATEDCOLLABORATIONISALSODETERMINEDBYTHECLIENT’SCAPACITYANDSTRATEGYTOORGANIZEINNOVATIVETENDERINGPROCEDURESSEBASTIANETAL,2009ECAM18,2178

簡介：淮陰工學院畢業(yè)設計外文資料翻譯學院院建筑工程學院專業(yè)業(yè)土木工程（路橋方向）姓名名石洋學號號1081401526外文出外文出處處工程力學雜志用外文寫JOURNALOFENGINEERINGMECHANICS附件件1外文資料翻譯譯文；2外文原文。附件附件1外文外文資料翻料翻譯譯譯譯文TIMOSHENKO和剪切模型梁的動力學研究NO?LCHALLAMEL1摘要古典TIMOSHENKO梁模型和剪切梁模型常用于建筑行為模型都剪穩(wěn)定性或動態(tài)分析。該技術關注的是兩種模型間的大量彎曲剪切剛度值的問題。這是以兩種模型分析研究了簡支梁。獲得大量彎曲剪切剛度值的漸進解。在一般情況下，實驗在考慮大彎剪剛度值參數(shù)時證明該剪切梁模型不能從TIMOSHENKO模型中推斷出來，這只是達到特定的幾何參數(shù)在目前的例子。作為結論，剪切模型的能力近似TIMOSHENKO模型，因為大量彎曲剪切剛度參數(shù)是堅定的依賴于橫截面在邊界狀態(tài)下的材料和幾何特性。關鍵詞橫波，結構力學，動態(tài)模型，腦電圖儀，比較研究。引言經典的TIMOSHENKO梁模型和剪切梁模型經常被用來模擬建筑物的剪切穩(wěn)定性和動態(tài)特性。該技術關注的是兩種模型間的大量彎曲剪切剛度值的問題。2004年ARISTIZABALOCHOA通過考慮大量無維參數(shù)來比較這兩種模型出一種關系，屈服于剪切剛度參數(shù)。這項科學證據(jù)表明一個簡單的例子這個參數(shù)可能不足以聯(lián)系這兩種理論。TIMOSHENKO模型動態(tài)方程TIMOSHENKO模型的控制方程是10X?Θ?EIΘX?Y?GAT?Θ?RM0X?Θ?GAX?Y?GAT??M22S222S22S2Y2這種橫梁只在楊氏模量和橫斷面剪切模量下用均勻的彈性材料制成的。它的橫向的橫截面是帶有一個用AS和一個重要的慣性矩表示的有效的剪切區(qū)域雙重對稱的IAR2。有效面積AS也能用ΚAΚ表示，所謂的剪切校正系數(shù)是一個給出了截面上的平均張力的比率和圖心剪切應變的無量綱的因數(shù)。它的重要取決

簡介：畢業(yè)設計外文文獻翻譯畢業(yè)設計外文文獻翻譯院系系土木工程與建筑系年級專年級專業(yè)業(yè)土木工程專業(yè)姓名名學號號附件件NANOTECHNOLOGYINCIVILENGINEERING指導老師評語指導教師簽名年月日2一、簡介一、簡介A．背景．背景作為建筑行業(yè)的人肯定都對獲得原材料，把它們組合在一起然后把它們構建成一個可識別的形式的概念非常熟悉。建筑成品是一個被動的物體。隨著環(huán)境影響和項目業(yè)主的濫用它的功能在慢慢衰退。建筑絕不是一門新的科學或技術，但在其歷史上已經發(fā)生了很大的變化。同樣，納米技術也不是一門新的科學和技術，而更可以說是一個擴展的科學和技術。粒子的大小是關鍵因素，在納米技術中（任何事物，從一百或者更多下降到幾納米，或109M）大大的改變了材料的特性。另一個重要方面是，作為納米尺寸的粒子，在表面上原子的比例相對于內部增加會產生新的屬性。正是這些“納米效應”，最終確定了我們所熟悉的“宏觀”的所有屬性，這正是納米技術的力量來源如果我們可以在納米尺寸上操縱元素，那就可以影響其宏觀性質，并產生新材料和新工藝。B．什么是納米．什么是納米納米，希臘文中”侏儒”的意思。一納米是一米的十億分之一?！奔{米技術”的定義有很多，但一般是指在01100NM尺度的空間內來研究理解物質?？刂圃诩{米尺寸上的意義與重要性是在這種范圍內不同的物理定律發(fā)揮作用（量子物理學）。接近納米級的方法有兩種從上而下收縮，或者自下而上發(fā)展?！白陨隙隆钡姆椒ㄐ枰獙⒔Y構通過加工和蝕刻技術減小到最小納米級尺寸，而“自下而上”的方法通常被稱為分子納米技術，意味著控制或定向原子和分子的組合來創(chuàng)建結構3。C．建筑納米技術．建筑納米技術20世紀90年代7初英國的德爾菲調查顯示建筑行業(yè)是唯一一個確定納米技術具有廣大前景的新興技術的行業(yè)。瑞典和英國建筑報告89中也強調了納米技術的重要性。此外，預制混凝土及混凝土制品被確定為在1015年間可能會受到納米技術影響的40個行業(yè)領域之首6。然而，建筑行業(yè)的發(fā)展滯后于其他工業(yè)部門，由此納米技術的研究吸引了大型工業(yè)企業(yè)和風險投資家的濃厚興趣和投資。意識到納米技術在建筑行業(yè)的巨大潛力和重要性，在2002年年底，歐盟委員會批準撥款給成長工程GMA1200272160”NANOCINEX”建立一個納米技術在建筑結

簡介：1使用加固纖維聚合物增強混凝土梁的延性使用加固纖維聚合物增強混凝土梁的延性作者NABILFGRACE,GEORGEABELSAYED,WAELFRAGHEB摘要摘要一種為加強結構延性的新型單軸柔軟加強質地的聚合物FRP已在被研究，開發(fā)和生產在結構測試的中心在勞倫斯技術大學。這種織物是兩種碳纖維和一種玻璃纖維的混合物，而且經過設計它們在受拉屈服時應變值較低，從而體現(xiàn)出偽延性的性能。通過對八根混凝土梁在彎曲荷載作用下的加固和檢測對研制中的織物的效果和延性進行了研究。用現(xiàn)在常用的單向碳纖維薄片、織物和板進行加固的相似梁也進行了檢測，以便同用研制中的織物加固梁進行性能上的比較。這種織物經過設計具有和加固梁中的鋼筋同時屈服的潛力，從而和未加固梁一樣，它也能得到屈服臺階。相對于那些用現(xiàn)在常用的碳纖維加固體系進行加固的梁，這種研制中的織物加固的梁承受更高的屈服荷載，并且有更高的延性指標。這種研制中的織物對加固機制體現(xiàn)出更大的貢獻。關鍵詞關鍵詞混凝土，延性，纖維加固，變形3研究意義研究意義FRP已經被越來越多地用做鋼筋混凝土結構修復和加固的材料。但是現(xiàn)在常用的FRP材料缺少延性，并且與鋼筋性能不一致。結果，經過加固處理的梁會體現(xiàn)出延性降低，不能達到期待中的水平，或者二者兼有。本項研究介紹了一種新型的偽延性FRP加固織物。這種織物可以使加固梁承受更高的屈服荷載，并且有助于避免延性的損失，而這在使用目前常用的FRP進行加固中是常見的?；祀s織物的研制混雜織物的研制為了克服前面所提的缺陷，一種具有低屈服應變值的延性FRP材料是很必要的?；祀s的文獻回顧為了研制這種材料，考慮了各種不同纖維的混雜。多于一種纖維材料的混雜是許多材料科學研究的興趣所在。他們的工作多數(shù)集中于結合兩種纖維以提高每種材料單獨工作時的力學特性并且降低成本。這已經在幾本出版物中報道過,例如BUNSEL和HARRIS（1974），PHILIPS（1976），MANDERS和BADER（1981），CHOW和KELLY（1980），以及FUKUDA和CHOW（1978）。做為一種能夠克服FRP加固棒延性不足問題的工具，混雜吸引了結構工程師。NANNI,HENNEKE和OKAMOTO（1994）研究了用編織芳香尼龍纖維繞在鋼筋核心的短棒。TAMUZS和TEPFORS報道了關于使用碳和芳香阻尼纖維進行組合而成的混合纖維棒的試驗調查。SOMBOONSONG，F(xiàn)RANK和HARRIS（1998）研制了一種用編織芳香尼龍纖維纏繞在碳纖維核心的混合FRP加固棒。HARRIS，SOMBOONSONG和FRANK（1998）使用這些棒對混凝土梁進行加固，以得到用常規(guī)鋼筋進行加固的混凝土梁的普通荷載撓度特性。設計思想和材料為了產生延性，一種使用不同種類纖維的混雜技術已經被采用。選用了在破壞時有不同延長量級的三種纖維。圖1顯示了這些復合纖維在拉伸時的應力應變曲線，表1顯示了它們的力學特性。這項技術是建立在將這些纖維結合起來并控制配合比例的基礎上的，這樣當它們被拉伸時共同承受荷載，延伸?。↙E）的纖維先破壞，允許一定的應

簡介：1粉煤灰含量和骨料級配在混凝土路面耐久性的影響粉煤灰含量和骨料級配在混凝土路面耐久性的影響SUKHVARSHJERATH,PE,MASCE1ANDNICHOLASHANSON2摘要摘要在溫度波動幅度很大的地區(qū)混凝土公路路面耐久性變差不是因為混凝土強度不夠。在這篇論文中將研究粉煤灰替代硅酸鹽水泥對密集級配骨料混凝土耐久性的影響。制作八個混凝土，其中四個使用骨料按現(xiàn)行規(guī)范其他四個用密集級配骨料。對于每個試件，粉煤灰替代硅酸鹽水泥的含量依次為30，35，和40。所有混凝土氣體含量為6和25–38毫米的坍落度。研究表明粉煤灰含量從30增加到45沒有損失混凝土的抗彎和抗壓強度。對于采用密集級配骨料的混凝土，高含量的粉煤灰需要更少的水表明粉煤灰和密集級配骨料對混凝土耐久性有影響。通過混凝土吸收率和孔隙率測試，混凝土中粉煤灰含量從30增加到45，滲透孔隙率比重隨之下降；在快速氯離子試驗中電荷通過量減少。這些實驗結果證明在混凝土中使用高含量的粉煤灰是很有益處的。使用致密級骨料也被證明是有益的。引言引言在高速公路由于冰凍和惡劣的天氣條件導致混凝土的破壞和耐久性問題已經被發(fā)現(xiàn)。水恰好是對混凝土耐久性極為重要，因此混凝土耐久性變得更強如果沒有易蒸發(fā)的水分殘留。如果使用孔隙率比較小的骨料級配，填補空隙所需的漿糊就更少反過來將減少易蒸發(fā)的水分。按照規(guī)范與標準粗骨料中大部分中等尺寸的顆粒將被去除。大量微小粒子組成的骨料做的漿糊能提高耐久性。粗、細骨料按照6040的比例組成的混合骨料叫做間斷級配骨料。在此混合骨料中沒有足夠多的中等尺寸的粒子，這些粒子可以在4號篩和16號篩之間篩選出來。MUSZYNSKI等人做了一份建筑施工記錄和路面內核的評估。工程建設自1987年到1997年以來差的混合配比和級配好的直接影響到道路施工的質量。研究表明,骨料級配控制是一種有效提高混凝土道路質量的方法。由GOLTERMANN等人在1997年表明骨料的選擇和組合對混凝土質量的影響是占主導因素。有一些主觀證據(jù)表明全級配骨料可以改善混凝土的性能在施工和使用期間,但它不是絕對令人信服的。1999年CRAMER和CARPENTER采用各種各樣普通試件關于全級配對混凝土凍融循環(huán)耐久性的影響進行試驗。粉煤灰的使用是符合和諧與可持續(xù)發(fā)展的理念。要大大增加粉煤灰的利用率，有必要提倡使用混凝土在其摻入大量的粉煤灰作為水泥的替代物。根據(jù)測試結果，得出的結論是高摻量粉煤灰加氣混凝土具有優(yōu)良的耐久性特性。在一篇JIANG和MALHOTRA的2000份研究結果，55不加氣混凝土中ASTM標準F類和C類粉煤灰替換水泥后水需求變少。試驗結果表明混凝土中粉煤灰含量從88變到194時水需求量降低。在ATISANDCELIK2002這本書里對高參量粉煤灰混凝土其中粉煤灰代替了50和70的水泥進行抗壓和抗彎性能評估。它表明在混凝土研究中混凝土的耐磨性跟彎曲抗拉強度的關系比抗壓強度大。佛羅里達州運輸部門用粉煤灰,礦渣,和不同類型的化學外加劑混替代水泥來研究合適的配合比用于夏季混凝土的澆筑。結果表明用粉煤灰和礦渣混合來替換水泥可以引起混凝土不同的性能。C類和F類粉煤灰分別替換70，67水泥來研究對混凝土路面的長期影響。對混凝土路3EXCEL進行數(shù)據(jù)分析，確定兩個均值之間是否存在統(tǒng)計上的顯著差異即P值。零假設，H0X?Y0，X和Y分別表示2個樣品，X是樣品中比較大的，是用來計算P值的。P值越小越能肯定零假設是失敗的，2個樣品就有不同的平均值。試驗結果試驗結果塑性特性實驗測試結果包括塑性，用間斷級配骨料和密集級配骨料制的混凝土，不同的粉煤灰代替水泥百分比。表3給出了不同混凝土混合物的單位重量的塑性，氣體含量和坍落度。水/膠凝材料的比率介于036037。氣體含量值介于57和64時坍落度依然保持在338和401MM。不同混凝土混合物的單位重量在2,3075和2,3661KG/M3之間變化。這表明,這些含量的值仍然保持恒定在這個研究中。抗壓強度對150300毫米的圓柱試件進行1，7，14，28，56，和90天的齡期測試。按ASTMC3901標準進行測試，3個圓柱試件某一齡期的平均值用來找出抗壓強度。不同混合物的測試結果在表4和圖1，2。P值是用來比較不同混凝土混合物之間的抗壓強度，混合物GG30的控制在表4?；炷粱旌衔锖懈弑壤姆勖夯议_發(fā)強度緩慢,然而,擁有更高百分比粉煤灰的混合物強度趕上甚至超過了在某些情況下粉煤灰含量低的混凝土抗壓強度。間斷級配的混合物粉煤灰含量3045在90天齡期后的抗壓強度達到2657MPA到2953MPA,P值介于00590105之間?？箟簭姸冉Y果為混凝土混合物含有密集級配骨料和更高比例的粉煤灰。在混凝土的抗壓強度影響最小的是密集級配骨料抗彎強度在150150300毫米的簡支梁第三點荷載進行測試按照ASTMC7802?？沽严禂?shù)是衡量混凝土抗彎強度。在每個試驗期測試3個混凝土梁的抗壓強度和平均抗彎強度。不同混凝土的斷裂系數(shù)在表5和圖3，4給出。P值從實驗數(shù)據(jù)計算并顯示在表5。粉煤灰比例高的混凝土在后期表現(xiàn)出更高的抗彎強度，雖然抗彎強度在早期低于粉煤灰比例低的混凝土。間斷級配和密集級配的混凝土也顯示這一趨勢。密集級配混凝土的抗彎強度略高于間斷級配混凝土?；炷恋谋戎兀章?，孔隙率這次測試是按照ASTMC642–97標準。它涵蓋了測定比重,吸收百分率,和孔隙。這種測試方法對混凝土是有用的，把質量/體積化轉為所用的數(shù)據(jù)。測試試件是來自試驗室鑄石板上鉆取的。每個澆筑的混凝土板都要鉆取。這些板上用塑料覆蓋7天,7天后的塑料被移開,該板塊仍在實驗室環(huán)境中放56天。試驗結果見表6。在所有混合物中比重值不同，吸收率變化也不大，表明混合物的設計和測試是正確的。另一方面對間斷級配和密集級配的混合物隨著粉煤灰比例的提高孔隙率隨之下降。這表明,該混合物中更高比例的粉煤灰具有低滲、高耐久性。快速氯離子滲透