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1、DataacquisitionDataacquisitionisthesamplingoftherealworldtogeneratedatathatcanbemanipulatedbyacomputer.SometimesabbreviatedDAQorDAS,dataacquisitiontypicallyinvolvesacquisitionofsignalsandwaveformsandprocessingthesignalstoobtaindesiredinformation.Thecompone
2、ntsofdataacquisitionsystemsincludeappropriatesensorsthatconvertanymeasurementparametertoanelectricalsignal,thenconditioningtheelectricalsignalwhichcanthenbeacquiredbydataacquisitionhardware.Acquireddataaredisplayed,analyzed,andstoredonacomputer,eitherusing
3、vendorsuppliedsoftware,orcustomdisplaysandcontrolcanbedevelopedusingvariousgeneralpurposeprogramminglanguagessuchasBASIC,C,Fortran,Java,Lisp,Pascal.SpecializedprogramminglanguagesusedfordataacquisitionincludeEPICS,usedtobuildlargescaledataacquisitionsystem
4、s,LabVIEW,whichoffersagraphicalprogrammingenvironmentoptimizedfordataacquisition,andMATLABwhichprovidesaprogramminglanguage,andalsobuilt-ingraphicaltoolsandlibrariesfordataacquisitionandanalysis.HowdataisacquiredSourceDataacquisitionbeginswiththephysicalph
5、enomenonorphysicalpropertyofanobject(underinvestigation)tobemeasured.Thisphysicalpropertyorphenomenoncouldbethetemperatureortemperaturechangeofaroom,theintensityorintensitychangeofalightsource,thepressureinsideachamber,theforceappliedtoanobject,ormanyother
6、things.Aneffectivedataacquisitionsystemcanmeasureallofthesedifferentpropertiesorphenomena.Atransducerisadevicethatconvertsaphysicalpropertyorphenomenonintoacorrespondingmeasurableelectricalsignal,suchasvoltage,current,changeinresistanceorcapacitorvalues,et
7、c.Theabilityofadataacquisitionsystemtomeasuredifferentphenomenadependsonthetransducerstoconvertthephysicalphenomenaintosignalsmeasurablebythedataacquisitionhardware.TransducersaresynonymouswithsensorsinDAQsystems.Therearespecifictransducersformanydifferent
8、applications,suchasmeasuringtemperature,pressure,orfluidflow.DAQalsodeployvarioussignalconditioningtechniquestoadequatelymodifyvariousdifferentelectricalsignalsintovoltagethatcanthenbedigitizedusingADCs.Signa