测绘工程专业英语复习资料

1Unit1WhatisGeomatics?Geomatics:WheredoesthewordGeomaticscomefrom?GEODESY+GEOINFORMATICS=GEOMATICSorGEO-forearthand-MATICSformathematicalorGEO-forGeoscienceand-MATICSforinformatics.Nowthetermincludesthetraditionalsurveyingdefinitionalongwithsurveyingsteadilyincreasedimportancewiththedevelopmentofnewtechnologiesandthegrowingdemandforavarietyofspatiallyrelatedtypesofinformation,particularlyinmeasuringandmonitoringourenvironment.Geomaticsbridgeswidearcsfromthegeosciencesthroughvariousengineeringsciencesandcomputersciencestospatialplanning,landdevelopmentandtheenvironmentalsciences.ISO:theInternationalStandardsOrganization(ISO)surveyor:Theterm“surveyor”istraditionallyusedtocollectivelydescribethoseengagedintheaboveactivities.Unit2GeodeticSurveyingandPlaneSurveyingGeodeticSurveying:Thetypeofsurveyingthattakesintoaccountthetrueshapeoftheearthiscalledgeodeticsurveying.Thistypeofsurveyissuitedforlargeareasandlonglinesandisusedtofindthepreciselocationofbasicpointsneededforestablishingcontrolforothersurveys.Ingeodeticsurveys,thestationsarenormallylongdistancesapart,andmorepreciseinstrumentsandsurveyingmethodsarerequiredforthistypeofsurveyingthanforplanesurveying.Geodeticcontrolsurveypoints:Widelyspaced,permanentmonumentsserveasthebasisforcomputinglengthsanddistancesbetweenrelativepositions.Thesebasicpointswithpermanentmonumentsarecalledgeodeticcontrolsurveypoints,whichsupporttheproductionofconsistentandcompatibledataforsurveyingandmappingprojects.PlaneSurveying:Thetypeofsurveyinginwhichthemeansurfaceoftheearthisconsideredaplane,orinwhichthecurvatureoftheearthcanbedisregardedwithoutsignificanterror,generallyiscalledplanesurveying.Thetermisusedtodesignatesurveyworkinwhichthedistancesorareasinvolvedareoflimitedextent.thecurvatureoftheearthmustbetakenintoconsiderationonlyinprecisesurveysoflargeareas.Surveysforthelocationandconstructionofhighways,railroads,canals,andingeneral,thesurveysnecessaryfortheworksofhumanbeingsareplanesurveys,asarethesurveysmadetoestablishboundaries,exceptstateandnational.Thereisclosecooperationbetweengeodeticsurveyingandplanesurveying.Thegeodeticsurveyadoptstheparametersdeterminedbymeasurementsoftheearth,anditsownresultsareavailabletothosewhomeasuretheearth.Theplanesurveys,inturn,aregenerallytiedtothecontrolpointsofthegeodeticsurveysandserveparticularlyinthedevelopmentofnationalmapseriesandintheformationofrealestatecadastres.2Unit3DistanceMeasurementElectronicDistanceMeasurement(EDM):EDMinstrumentsrefertothedistancemeasurementequipmentsusinglightandradiowaves.Bothlightwavesandradiowavesareelectromagnetic.TheadventofEDMinstrumenthascompletelyrevolutionizedallsurveyingprocedures,resultinginachangeofemphasisandtechniques.优点：Distancecannowbemeasuredeasily,quicklyandwithgreataccuracy,regardlessofterrainconditions.分类：TheEDMinstrumentsmaybeclassifiedaccordingtothetypeandwavelengthoftheelectromagneticenergygeneratedoraccordingtotheiroperationalrange.EDMinstrumentsusethreedifferentwavelengthbands:(1)Microwavesystemswithrangeupto150km,wavelength3cm,notlimitedtolineofsightandunaffectedbyvisibility;(2)Lightwavesystemswithrangeupto5km(forsmallmachines),visiblelight,lasersanddistancereducedbyvisibility;(3)Infraredsystemswithrangeupto3km,limitedtolineofsightandlimitedbyrain,fog,otherairborneparticles.两种方法：Therearebasicallytwomethodsofmeasurementemployedwhichmaydividetheinstrumentsintotwoclassificationaselectro-optical(lightwaves)andmicrowaves(radiowaves)instruments.Thesetwobasicmethodsarenamelythepulsemethodandmorepopularphasedifferentmethod.Theyfunctionbysendinglightwavesormicrowavesalongthepathtobemeasuredandmeasuringthetimedifferencesbetweentransmittedandreceivedsignals,orinmeasuringthephasedifferencesbetweentransmittedandreceivedsignalsinreturningthereflectinglightwavetosource.Unit4AngleandDirectionMeasurementAverticalline:Averticallineatanypointontheearth’ssurfaceisthelinethatfollowsthedirectionofgravityatthatpoint.Itisthedirectionthatastringwillassumeifaweightisattachedatthatpointandthestringissuspendedfreelyatthepoint.Atagivenpointthereisonlyoneverticalline.Ahorizontalline:Ahorizontallineatapointisanylinethatisperpendiculartotheverticallineatthepoint.Atanypointthereareanunlimitednumberofhorizontallines.Ahorizontalplane:Ahorizontalplaneatapointistheplanethatisperpendiculartotheverticallineatthepoint.Thereisonlyonehorizontalplanethroughagivenpoint.Averticalplane:Averticalplaneatapointisanyplanethatcontainstheverticallineatthepoint.Thereareanunlimitednumberofverticalplanesatagivenpoint.Ahorizontalangle:Ahorizontalangleistheangleformedinahorizontalplanebytwointersectingverticalplanes,orahorizontalanglebetweentwolinesistheanglebetweentheprojectionsofthelinesontoahorizontalplane.Averticalangle:Averticalangleisananglemeasuredinaverticalplanewhichisreferencedtoahorizontallinebyplus(up)orminus(down)angles,ortoaverticallinefromthezenithdirection.Zenith:Zenithisthetermdescribingpointsonacelestialspherethatisasphereofinfinitelylargeradiuswithitscenteratthecenteroftheearth.Azimuth:Azimuthisthehorizontalanglemeasuredi