Unit2GeodeticSurveyingandPlaneSurveying（大地测量与平面测量）Surveyinghasbeentraditionallydefinedastheartandscienceofdeterminingthepositionofnaturalandartificialfeatureson,aboveorbelowtheearth’ssurface;andrepresentingthisinformationinanalogformasacontouredmap,paperplanorchart,orasfiguresinreporttables,orindigitalformasathreedimensionalmathematicalmodelstoredinthecomputer.（测量传统定义为确定地表、地下和地上的自然与人工地貌特征【features形态、特征】；并使之按比例【inanalogform】测绘成地形图【contouredmap】、平面图【paperplan】或图表，或形成报告图表，或以数字形式形成三维立体数学模型存储进计算机。）Assuch,thesurveyor/geodesistdealtwiththephysicalandmathematicalaspectofmeasurement.（同样的，测量员/大地测量学家处理的就是测量出的物理的和数学的特征）Theaccuratedeterminationandmonumentation【标石、标志】ofpointsonthesurfaceoftheEarthisthereforeseenasthemajortask.（因此精确确定并标定地表点位便成为测量的主要任务）Thoughthesesurveysareforvariouspurposes,stillthebasicoperationsarethesame---theyinvolvemeasurementsandcomputationsor,basically,fieldworkandofficework.（虽然测量工作有不同目的，基本的操作却都一样――他们包括测量和计算，或更基本地称之为，外业工作和内业工作）Therearemanydifferenttypesofsurveyssuchaslandsurveys,routesurveys,citysurveys,constructionsurveys,hydrographicsurveys,etc.,butgenerallyspeaking,surveyingisdividedintotwomajorcategories:geodeticandplanesurveying.（测量分为许多不同的类型，如土地测量，路线测量，城市测量，建筑测量，水道测量等等，但是总的来说，测量分为两个主要的种类：大地测量和平面测量）SurveyswilleithertakeintoaccountthetrueshapeoftheEarth（Geodeticsurveys）ortreattheearthasaflatsurface(Planesurveys).（是考虑地球真实形状的大地测量还是将地球当成一个平面的平面测量【紧跟着上句】）Additionally,surveysareconducted【表现】forthepurposeofpositioningfeaturesontheground(Horizontalsurveys),determiningtheelevationorheightsoffeatures(Verticalsurveys)oracombinationofboth.（另外，测量还分为确定平面位置的水平测量和确定海拔的高程测量或两者的综合。）GeodeticSurveying（大地测量）Thetypeofsurveyingthattakesintoaccountthetrueshapeoftheearthiscalledgeodeticsurveying.（考虑地球真实形状的测量工作称为大地测量）Thistypeofsurveyissuitedforlargeareasandlonglinesandisusedtofindthepreciselocationofbasicpointsneededforestablishingcontrolforothersurveys.（这种测量适用于大范围和长距离的测量工作，用来确立基本点的精确位置，用以建立其他测量工作所需的控制网。）Ingeodeticsurveys,thestationsarenormallylongdistancesapart,andmorepreciseinstrumentsandsurveyingmethodsarerequiredforthistypeofsurveyingthanforplanesurveying.（在大地测量中，站点经常是互相距离很远，那么这种测量就比平面测量需要更精确的仪器和测量方法。）Widelyspaced,permanentmonumentsserveasthebasisforcomputinglengthsanddistancesbetweenrelativepositions.（广泛间隔开的永久标石就作为计算点位之间距离的基础）【serve当作】Thesebasicpointswithpermanentmonumentsarecalledgeodeticcontrolsurveypoints,whichsupporttheproductionofconsistentandcompatibledataforsurveyingandmappingprojects.（这种永久标石点被称为大地控制点，为测量和绘图工作提供可靠和一致的数据）Inthepast,ground-basedtheodolites,tapes【卷尺】,andelectronicdevicesweretheprimarygeodeticfieldmeasurementsused.（过去，大地经纬仪【DJ大地经纬仪的中文缩写】、卷尺和电子设备是大地测量的野外工作初时【primary】的工具。）Today,thetechnologicalexpansionofGPShasmadeitpossibletoperformextremelyaccuratege...
VIP
