外文翻译--- 高精度温度测量装置的设计

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1、附录ADesignofaHighPrecisionTemperatureMeasurementSystem1IntroductionSensorsareoneofthemostimportantelementsusedinmanyinstrumentationcircuits.Theyareusedinmanyindustrialapplicationsandtakeacertainformofinput(temperature,pressure,altitude,etc.)andconvertitintoreadingsthatcanbeinterpreted.Manytypesofs

2、ensorsarenonlinearinnaturefromwhichalinearoutputisdesired.Therearemanydifferentsensorsfortemperaturemeasurementandthermocouplesarethemostcommonlyused.Theyarepreferredinindustrialapplicationsduetotheirlowcost,wideoperationrange,fastresponsetimeandaccuratewhentheirpeculiaritiesareunderstood.Thermoc

3、oupleshavealsooutputsnonlinearlyrelatedtotemperature.Therefore,sensormodelingandlinearizationtechniquesarenecessary.Tosolvethelinearizationproblemofasensor,therearegenerallytwomethodsproposed.Thefirstonerequiresnonlinearanalogcircuitandthesecondusesnumericalmethodsthatarecomputedbymicroprocessoro

4、rcomputer.Analogcircuitsarefrequentlyusedforimprovingthelinearityofthesensorcharacteristics,whichimpliesadditionalanaloghardwareandtypicalproblemsassociatedtoanalogcircuitssuchastemperaturedrift,gainandoffseterror.Usingthesecondmethod,sensornonlinearitiescanbecompensatedbymeansofarithmeticoperati

5、ons,ifanaccuratesensormodelisavailable(directcomputationofthepolynomials),oruseofamultidimensionallook-uptable.Directcomputationofthepolynomialmethodismoreaccuratebuttakesalongtimeforcomputation,whilethelook-uptablemethod,thoughfaster,isnotveryaccurate.Inrecentyears,applicationofANNshasemergedasa

6、promisingareaofresearchinthefieldofinstrumentationandmeasurement.Itprovidesaneurocomputingapproachforsolvingcomplexproblemsespeciallyinnonlinearsystemmodelingwhichthenetworkitselfisanonlinearsystem.Thisisextremelyusefulwhentheareaofinterestisabsolutelynonlinearincludingtheexperimentaldatathatisus

7、edfortraining.OneofthemostpowerfulusesofANNsisinfunctionapproximation(curvefitting).InterpolationbasedonANNprovideslowerinterpolationerrorswhencomparedwithconventionalnumericalinterpolation.Intheworkwepresenthere,highp