測(cè)繪工程專業(yè)英語翻譯1~6.docx

Uuit1 What is Geomatics? （什么是測(cè)繪學(xué)）Geomatics Defined（測(cè)繪學(xué)定義） Where does the word Geomatics come from?（Geomatics測(cè)繪或地球空間信息學(xué)，這個(gè)名詞 是怎么來的呢？） GEODESY+GEOINFORMATICS=GEOMATICS or GEO- for earth and MATICS for mathematical or GEO- for Geoscience and -MATICS for informatics. （大地測(cè)量學(xué)地理信息 學(xué)GEOMATICS 測(cè)繪學(xué)或者 geo 代表地球，matics 代表數(shù)學(xué)，或者 geo 代表地球科學(xué)， matics 代表信息學(xué)）It has been said that geomatics is many things to many people.（據(jù)說測(cè) 繪學(xué)這個(gè)詞對(duì)不同的人有不同的理解） The term geomatics emerged first in Canada and as an academic discipline; it has been introduced worldwide in a number of institutes of higher education during the past few years, mostly by renaming what was previously called “geodesy” or “surveying”, and by adding a number of computer scienceand/or GIS-oriented courses.（這 個(gè)術(shù)語作為一個(gè)學(xué)科第一次形成于加 拿大；在過去的幾年里被全世界的許多高等教育研究機(jī)構(gòu)所熟知，通常是以前的“大地測(cè)量 學(xué)”或“測(cè)量學(xué)”在引入了許多計(jì)算機(jī)科學(xué)和 GIS 方向的課程后重新命 名的。 ） Now the term includes the traditional surveying definition along with surveying steadily increased importance with the development of new technologies and the growing demand for a variety of spatially related types of information, particularly in measuring and monitoring our environment.（隨著新技術(shù)的發(fā)展和不斷增長(zhǎng)的對(duì)空間關(guān)系的信息類型的需求，尤其是在測(cè) 量和監(jiān)測(cè)我們的環(huán)境方面 ， 現(xiàn)在， 傳統(tǒng)測(cè)量學(xué)定義連同 日益增長(zhǎng)的測(cè)量的重要性一起包含在這個(gè)術(shù)語里了。） Increasingly critical are areas of expanding populations, appreciating land values, dwindling natural resources, and the continuing stressing of the quality of our land, water and air from human activities. （日益增長(zhǎng)的危機(jī)來自人口擴(kuò)張，地價(jià)上漲，資源緊縮【緊張】 ，還有由于 人類活動(dòng)引起的土地、水、空氣質(zhì)量的持續(xù)的壓力 As such, geomatics bridges wide arcs from the geosciences through various engineering sciences and computer sciences to spatial planning, land development and the environmental sciences.（這樣，測(cè)繪學(xué)在地球科學(xué)，各種工程學(xué)，計(jì)算機(jī)科 學(xué)， 空間規(guī)劃， 土地開發(fā)和環(huán)境科學(xué)相互之間架起了廣泛的橋梁。 ） Now the word geomatics has been adopted by several international bodies including the International Standards Organization(ISO),so it is here to stay.（現(xiàn)在 geomatics 這個(gè)詞已經(jīng)被包括 ISO在內(nèi)的數(shù)個(gè)國(guó)際機(jī)構(gòu) 所采用， 因此它就這樣被普遍接受 The term “surveyor” is traditionally used to collectively describe those engaged in the above activities. （surveyor 這個(gè)詞按慣例用來總指 （這換成 “總 稱” 較好） 那些從事上述活動(dòng)的人。 ） More explicit job descriptions such as Land Surveyor, Engineering Surveyor or Hydrographic Surveyor for example, are commonly used by practitioners to more clearly describe and market their specialized expertise. （更具體的工作如土地測(cè)量員、工程測(cè)量員和水道測(cè)量員，被業(yè)內(nèi)人士用來更準(zhǔn)確的描述他們的專門技術(shù)。 The term geomatics is a recent creation to convey the truecollective and scientific nature of these related activities and has the flexibility to allow for theincorporation of future technological developments in these fields.（geomatics 這個(gè)術(shù)語是個(gè)新 詞，表達(dá)了實(shí)體集合和它們相關(guān)聯(lián)的活動(dòng)的自然科學(xué)，并使這些領(lǐng)域的未來技術(shù)發(fā)展的結(jié)合成為可能。）Adoption of the term also allows a coherent marketing of the profession to industry and schools on a worldwide basis. （這個(gè)術(shù)語的采用同時(shí)也在全世界范圍里為行業(yè)里和學(xué)校建立了一個(gè)一致的專業(yè)市場(chǎng)） As a result, both course and awardtitles in the traditional Land Surveying sector at many of the world s leading universities are being changed to “Degree in Geomatics”. （結(jié)果，世界上許多一流大學(xué)的傳統(tǒng)的測(cè)量專業(yè)的無論是課程還是授予資格都改為“測(cè)繪學(xué)位”的了） This does not suggest the demise of the term “surveyor” and graduates will still practice as land surveyors or photogammertrists, etc. as appropriate to their specialization.（這并不意味著“surveyor”這個(gè)詞的消亡，測(cè)繪畢業(yè)生還將從事適合他們專業(yè)的土地測(cè)量員、攝影測(cè)量員及其他的工作） In the last decade, there has been dramatic development and growth in the use of hardware and software solutions to both measure and process geo-spatial data.（在過去的十年中，在應(yīng)用硬件和軟件的方法來測(cè)量和處理地球空間數(shù)據(jù)工作時(shí)有著戲劇性的發(fā)展和增長(zhǎng)）This has created and will continue to create new areas of application, with associated job opportunities for suitably qualified graduates. （創(chuàng)造并將繼續(xù)創(chuàng)造新的應(yīng)用領(lǐng)域，并為合適的、合格的畢業(yè)生提供相關(guān)的工作。） As a result, the role of the “surveyor” is expanding beyond traditional areas of practice, as described above, into new areas of opportunity.（結(jié)果是，“surveyor”的角色大大超越傳統(tǒng)實(shí)踐領(lǐng)域如前面所述的領(lǐng)域，進(jìn)入到新的領(lǐng)域。） In addition, recent advances in the technology of data collection and processing have blurred the boundaries of practice and activity between what were previously regarded as related but separate areas.（另外，最近的數(shù)據(jù)采集和處理技術(shù)的發(fā)展模糊了以前被認(rèn)為有聯(lián)系卻分離的領(lǐng)域的界限） Such developments are forecast to continue and willcreate new career paths for graduates whose education and training is broadly based and of a high academic standard.（可以預(yù)見，這種發(fā)展繼續(xù)并將為涉獵廣泛、學(xué)識(shí)一流的畢業(yè)生創(chuàng)造新的事業(yè)。） To enable graduatesto take full advantage of these developments, significant changes in education and training are required.（為了使畢業(yè)生能充分利用這些發(fā)展，教育和訓(xùn)練的重大改革成為必需的） Academic and professional institutions are also responding, in part, by adopting the term geomatics both as a course and as an award title. （學(xué)院的和專業(yè)的機(jī)構(gòu)也作出反應(yīng)，部分地，采用術(shù)語“geomatics”作為一門課程和一項(xiàng)授予資格）。 A working definition of geomatics, which reflects current thinking and predicted change, is:（測(cè)繪學(xué)的一個(gè)現(xiàn)在使用的反映了當(dāng)前的思想和對(duì)未來的預(yù)期的定義是：）The science and technology of acquiring, storing, processing, managing, analyzing and presenting geographically referenced information(geo-spatial data ).（獲取、處理、存儲(chǔ)，分析和上呈地理參考信息（地理空間信息）的科學(xué)和技術(shù)。） This broad term applies both to science and technology, and mapping, geodesy, satellite positioning, photogrammetry, remote sensing, geographic information systems(GIS), land management ,computer systems, environmental visualization and computer graphics.（這個(gè)廣泛的術(shù)語應(yīng)用于科學(xué)和技術(shù)，以及制圖、大地測(cè)量學(xué)、衛(wèi)星定位、攝影測(cè)量學(xué)、遙感、地理信息系統(tǒng)、土地管理、計(jì)算機(jī)系統(tǒng)、環(huán)境可視化和計(jì)算機(jī)制圖等領(lǐng)域） Several terms such as “geomatics” , “geomatic engineering,” and “geoinformatics” are now in common use pertaining to activities generally concerned with geographic information.（現(xiàn)在一些術(shù)語如“測(cè)繪學(xué)”，“測(cè)繪工程”“地學(xué)信息學(xué)”和共同應(yīng)用于某些活動(dòng)中專屬于通常涉及地理信息的活動(dòng)。） These terms have been adopted primarily to represent the general approach that geographic information is collected, managed, and applied. （這些術(shù)語起初被采用用來表示地理信息的采集、管理和應(yīng)用的總體的方法。） Along with land surveying, photogrammetry, remote sensing, and cartography, GIS is an important component of geomatics. （連同土地測(cè)量學(xué)，攝影測(cè)量學(xué)，遙感和制圖學(xué)一起，GIS 也是測(cè)繪學(xué)中重要的一個(gè)組成部分。）Branches of Geomatics（測(cè)繪學(xué)分支）Data acquisition techniques include field surveying, global positioning system(GPS), satellite positioning, and remotely sensed imagery obtained through aerial photography and satellite imagery. （數(shù)據(jù)獲取技術(shù)包括普通野外測(cè)量，GPS 測(cè)量，衛(wèi)星定位和遙感圖像獲取，通過航空攝影和衛(wèi)星成像） It also includes the acquisition of database material scanned from older maps and plans and data collected by related agencies.（它還包括數(shù)據(jù)庫資料的獲取通過掃描就有地圖和設(shè)計(jì)圖，還有有關(guān)機(jī)構(gòu)收集的數(shù)據(jù)。） Data management and process are handled through the use of computer programs for engineering design, digital photogrammetry, image analysis, relational data base management, and geographic information systems (GIS).（通過計(jì)算機(jī)程序，數(shù)據(jù)管理和處理應(yīng)用于工程設(shè)計(jì)，數(shù)字?jǐn)z影測(cè)量，圖像分析，相關(guān)資料庫的管理和 GIS。） Data plotting(presentation) is handled through the use of mapping and other illustrative computer programs; the presentations are displayed on computer screens(where interactive editing can occur) and are output on paper from digital plotting devices.（數(shù)據(jù)成圖是通過制圖和其他直觀的計(jì)算機(jī)程序進(jìn)行的；其表達(dá)顯示在計(jì)算機(jī)屏幕上（交互式編輯處理），也可以通過數(shù)字繪圖儀輸出到紙上。） Once the positions and attributes of geographicentities have been digitized and stored in computer memory, they are available for use by a wide variety of users.（一旦地理實(shí)體的位置和屬性被數(shù)字化并被存儲(chǔ)進(jìn)計(jì)算機(jī)存儲(chǔ)器，就可以有效的為廣泛的各種的使用者所用） Through the use of modern information technology(IT), geomatics brings together professionals in the following disciplines: surveying, mapping, remote sensing, land registration, civil and marine engineering, forestry,agriculture, planning and development, geology, geographical sciences, infrastructuremanagement, navigation, environmental and natural resources monitoring, and computerscience.（通過現(xiàn)代信息技術(shù)，測(cè)繪學(xué)將以下學(xué)科的專業(yè)人員整合到一起：測(cè)量學(xué)、制圖學(xué)、遙感、國(guó)土注冊(cè)、土木工程和海洋工程，林業(yè)，農(nóng)業(yè)，決策與發(fā)展，地質(zhì)學(xué)，地理科學(xué)，基礎(chǔ)設(shè)施管理，導(dǎo)航，環(huán)境與自然資源監(jiān)測(cè)和計(jì)算機(jī)科學(xué)。）Other Definitions of Geomatics （測(cè)繪學(xué)的其他定義）As defined by the Canadian Institute of Geomatics in their quarterly journal “Geomatica”: Geomatics is a field of activities which, using a systemic approach, integrates all the means used to acquire and manage spatial data required as part of scientific, administrative, legal and technical operations involved in the process of the production and management of spatial information. （加拿大測(cè)量學(xué)會(huì)在他們的季刊“地球空間信息學(xué)”中這樣定義：測(cè)繪學(xué)是利用系統(tǒng)的方法，為生產(chǎn)和處理科學(xué)的，行政的，法律的和技術(shù)的業(yè)務(wù)所需的空間信息，將所有獲取和管理空間信息的方法整合在一起的活動(dòng)領(lǐng)域的一部分The definition of Geomatics is evolving. A working definition might be “ the art, science and technologies related to the management of geographically-referenced information.” Geomatics includes a wide range of activities, from the acquisition and analysis of site-specific spatial data in engineering and development surveys to the application of GIS and remote sensing technologies in environmental management. It includes cadastral surveying, hydrographic surveying, and ocean mapping, and it plays an important role in land administration and land use management .（測(cè)繪學(xué)定義在發(fā)展?，F(xiàn)行的一個(gè)定義是“涉及工藝、科學(xué)和技術(shù)的地理信息的處理”。測(cè)繪學(xué)或地球空間信息學(xué)包括一個(gè)廣泛的生產(chǎn)活動(dòng)從工程學(xué)和發(fā)展了的測(cè)量學(xué)領(lǐng)域中特殊點(diǎn)的空間數(shù)據(jù)的獲取和分析到 GIS 和遙感技術(shù)在環(huán)境管理中的應(yīng)用。它包括地籍測(cè)量、水道測(cè)量和海圖測(cè)量，在土地管理和土地使用中扮演重要的角色。）Geomatics is the modern scientific term referring to the integrated approach of measurement, analysis, management, storage and display of the descriptions and location of Earthbased data, often termed spatial data. These data come from many sources, including earth orbiting satellites, air and sea-borne sensors and ground based instruments. It is processed and manipulated with state-of-the-art information technology using computer software and hardware. It has applications in all disciplines which depend on spatial data, including environmental studies, planning, engineering, navigation, geology and geophysics, oceanography, land development and land ownership and tourism. It is thus fundamental to all the geoscience disciplines which use spatially related data .（測(cè)繪學(xué)是一個(gè)現(xiàn)代科學(xué)術(shù)語，用以表示測(cè)量、分析、管理，存儲(chǔ)和顯示基于地球信息，經(jīng)常被稱為空間數(shù)據(jù) 數(shù)據(jù)的描述和位置的集成方法。這些數(shù)據(jù)來自各種數(shù)據(jù)源，包括地球軌道衛(wèi)星，空載和艦載傳感器及地面儀器。利用計(jì)算機(jī)軟件和硬件，借助現(xiàn)代信息技術(shù)。它的應(yīng)用覆蓋所有依賴空間數(shù)據(jù)的學(xué)科，包括環(huán)境研究，規(guī)劃，工程學(xué)，導(dǎo)航，地質(zhì)和地球物理學(xué)，海洋學(xué)，土地開發(fā)，土地經(jīng)營(yíng)和旅游學(xué)。它因而成為所有使用空間數(shù)據(jù)地球科學(xué)學(xué)科的基礎(chǔ)。） from the School of Geomatic Engineering, Univ. of New South Wales（摘自新南威爾士大學(xué)測(cè)繪工程學(xué)院）Geomatics is concerned with the measurement, representation, analysis, management, retrieval and display of spatial data concerning both the Earths physical features and the built environment. The principal disciplines embraced by Geomatics include the mapping sciences, land management, geographic information systems, environmental visualization, geodesy, photogrammetry, remote sensing and surveying. （測(cè)繪學(xué)是測(cè)量、表示，分析，處理，重獲和顯示關(guān)于地球物理特征和環(huán)境的空間數(shù)據(jù)的科學(xué)。其包括的主要學(xué)科有制圖學(xué)，土地管理，GIS，環(huán)境可視化，大地測(cè)量學(xué)，攝影測(cè)量學(xué)，遙感和測(cè)量學(xué)。） from the Dept. of Geomatics at Univ. of Melbourne（摘自墨爾本大學(xué)測(cè)繪學(xué)系Geomatics comprises the science, engineering, and art involved in collecting and managing geographically-referenced information. Geographical information plays an important role in activities such as environmental monitoring, management of land and marine resources, and real estate transactions. （測(cè)繪學(xué)包括自然科學(xué)，工程學(xué)和工藝或?qū)W；對(duì)地理信息的收集與管理。地理信息在環(huán)境監(jiān)測(cè)，陸地和海洋資源管理，以及房地產(chǎn)交易中扮演重要角色。 from the Dept. of Geodesy and Geomatics Engineering at UNB（摘自加拿大紐布朗斯維克大學(xué)測(cè)量與大地測(cè)量學(xué)系）The science of Geomatics is concerned with the measurement, representation, analysis,management, retrieval and display of spatial information describing both the Earths physicalfeatures and the built environment. Geomatics includes disciplines such as : Surveying, Geodesy,Remote Sensing & Photogrammetry, Cartography, Geographic Information Systems, Global PositioningSystems. （測(cè)繪學(xué)測(cè)量，表示，分析，管理，重獲和顯示空間信息，用來描述地球物理特征和環(huán)境。測(cè)繪學(xué)包括的學(xué)科有：測(cè)量學(xué)，大地測(cè)量學(xué)，遙感和攝影測(cè)量學(xué)，制圖學(xué)，GIS，GPS ） from the Dept. of Sruveying and Spatial Information Science at the Univ. of Tasmania （摘自塔斯馬尼亞大學(xué)，測(cè)量與空間信息科學(xué)系）Unit 2 Geodetic Surveying and Plane Surveying（大地測(cè)量與平面測(cè)量）Surveying has been traditionally defined as the art and science of determining the position of natural and artificial features on, above or below the earths surface; and representing this information in analog form as a contoured map, paper plan or chart, or as figures in report tables, or in digital form as a three dimensional mathematical model stored in the computer. （測(cè)量傳統(tǒng)定義為確定地表、地下和地上的自然與人工地貌特征；并使之按比例測(cè)繪成地形圖、平面圖或圖表，或形成報(bào)告圖表，或以數(shù)字形式形成三維立體數(shù)學(xué)模型存儲(chǔ)進(jìn)計(jì)算機(jī)。） As such, the surveyor/geodesist dealt with the physical and mathematical aspect of measurement. （同樣的，測(cè)量員/大地測(cè)量學(xué)家處理的就是測(cè)量出的物理的和數(shù)學(xué)的特征） The accurate determination and monumentation of points on the surface of the Earth is therefore seen as the major task. （因此精確確定并標(biāo)定地表點(diǎn)位便成為測(cè)量的主要任務(wù)）Though these surveys are for various purposes, still the basic operations are the same-they involve measurements and computations or, basically, fieldwork and office work. （雖然測(cè)量工作有不同目的，基本的操作卻都一樣他們包括測(cè)量和計(jì)算，或更基本地稱之為，外業(yè)工作和內(nèi)業(yè)工作） There are many different types of surveys such as land surveys, route surveys, city surveys, construction surveys, hydrographic surveys, etc., but generally speaking, surveying is divided into two major categories: geodetic and plane surveying. （測(cè)量分為許多不同的類型，如土地測(cè)量，路線測(cè)量，城市測(cè)量，建筑測(cè)量，水道測(cè)量等等，但是總的來說，測(cè)量分為兩個(gè)主要的種類：大地測(cè)量和平面測(cè)量） Surveys will either take into account the true shape of the Earth（Geodetic surveys） or treat the earth as a flat surface(Plane surveys). （是考慮地球真實(shí)形狀的大地測(cè)量還是將地球當(dāng)成一個(gè)平面的平面測(cè)量） Additionally, surveys are conducted for the purpose of positioning features on the ground(Horizontal surveys), determining the elevation or heights of features(Vertical surveys) or a combination of both.（另外，測(cè)量還分為確定平面位置的水平測(cè)量和確定海拔的高程測(cè)量或兩者的綜合。）Geodetic Surveying（大地測(cè)量）The type of surveying that takes into account the true shape of the earth is called geodetic surveying. （考慮地球真實(shí)形狀的測(cè)量工作稱為大地測(cè)量） This type of survey is suited for large areas and long lines and is used to find the precise location of basic points needed for establishing control for other surveys. （這種測(cè)量適用于大范圍和長(zhǎng)距離的測(cè)量工作，用來確立基本點(diǎn)的精確位置，用以建立其他測(cè)量工作所需的控制網(wǎng)。） In geodetic surveys, the stations are normally long distances apart, and more precise instruments and surveying methods are required for this type of surveying than for plane surveying.（在大地測(cè)量中，站點(diǎn)經(jīng)常是互相距離很遠(yuǎn)，那么這種測(cè)量就比平面測(cè)量需要更精確的儀器和測(cè)量方法。） Widely spaced, permanent monuments serve as the basis for computing lengths and distances between relative positions. （廣泛間隔開的永久標(biāo)石就作為計(jì)算點(diǎn)位之間距離的基礎(chǔ)）These basic points with permanent monuments are called geodetic control survey points, which support the production of consistent and compatible data for surveying and mapping projects. （這種永久標(biāo)石點(diǎn)被稱為大地控制點(diǎn)，為測(cè)量和繪圖工作提供可靠和一致的數(shù)據(jù)）In the past, ground-based theodolites, tapes , and electronic devices were the primary geodetic field measurements used. （過去，大地經(jīng)緯儀、卷尺和電子設(shè)備是大地測(cè)量的野外工作初時(shí)的工具。） Today, the technological expansion of GPS has made it possible to perform extremely accurate geodetic surveys at a fraction of the cost.（現(xiàn)在，技術(shù)的發(fā)展 GPS使大地測(cè)量工作花費(fèi)非常小的代價(jià)就能獲得極為精確的結(jié)果成為可能。） A thorough knowledge of the principles of geodesy is an absolute prerequisite for the proper planning and execution of geodetic surveys.（大地測(cè)量工作計(jì)劃的編制和實(shí)施，絕對(duì)需要對(duì)大地測(cè)量學(xué)知識(shí)有全面的掌握。）In Geodetic Surveys, the shape of the earth is thought of as a spheroid, although in a technical sense, it is not really a spheroid. （在大地測(cè)量中，地球的形狀被看成一個(gè)橢球體，雖然在技術(shù)角度來看，它不是真正的橢球。） Therefore, distances measured on or near the surface of the earth are not along straight lines or planes, but on a curved surface.（因此，在地球表面上或附近測(cè)量距離并不是沿著直線或平面進(jìn)行，而是在一個(gè)曲面上。) Hence, in the computation of distances in geodetic surveys, allowances are made for the earths minor and major diameters from which a spheroid of reference is developed. （因此，在大地測(cè)量距離的計(jì)算中，參考橢球的長(zhǎng)軸與短軸所帶來的誤差就顯示出來。） The position of each geodetic station is related to this spheroid.（每個(gè)大地站點(diǎn)的位置都與這個(gè)橢球有關(guān)） The positions are expressed as latitudes(angles north or south of the Equator) and longitudes(angles east or west of a prime meridian) or as northings and eastings on a rectangular grid.（這個(gè)位置是用緯度（與赤道面所成的角）和經(jīng)度（與初子午線所成的角）或用在直角坐標(biāo)系中的北距和東距來表示。） A geodetic survey establishes the fundamentals for the determination of the surface and gravity field of a country. （大地測(cè)量為建立國(guó)家范圍內(nèi)的重力場(chǎng)和確定地表架構(gòu)提供基礎(chǔ)） This is realized by coordinates and gravity values of a sufficiently large number of control points, arranged in geodetic and gravimetric networks.（這將由測(cè)定布設(shè)在大地網(wǎng)和重力網(wǎng)中數(shù)量十分巨大的控制點(diǎn)，所得到的坐標(biāo)和重力值來實(shí)現(xiàn)） In this fundamental work, curvature and the gravity field of the earth must be considered.（在這項(xiàng)基礎(chǔ)工作中，地球的曲率和重力場(chǎng)都應(yīng)被考慮。）Plane Surveying（平面測(cè)量）The type of surveying in which the mean surface of the earth is considered a plane, or in which the curvature of the earth can be disregarded without significant error, generally is called plane surveying.（這種類型的測(cè)量把地球平均的表面視作平面，或認(rèn)為地球曲率帶來的誤差可以忽略不計(jì)，這樣的測(cè)量工作稱為平面測(cè)量） The term is used to designate survey work in which the distances or areas involved are of limited extent.（這個(gè)術(shù)語曾指涉及的距離及范圍非常有限的測(cè)量工作） With regard to horizontal distances and directions, a level line is considered mathematically straight, the direction of the plumb line is considered to be the same at all points within the limits of the survey, and all angles are considered to be plane angles.（由于被當(dāng)成了水平距離和方向，水平線被當(dāng)成直線，在這個(gè)有限范圍內(nèi)所有點(diǎn)上的鉛垂線方向被認(rèn)為是相同的，所有的角被認(rèn)為都是平面角。） To make computations in plane surveying, you will use formulas of plane trigonometry, algebra, and analytical geometry. （在平面測(cè)量的計(jì)算中，你可以使用平面三角、代數(shù)、和平面解析幾何的公式） For small areas, precise results may be obtained with planesurveying methods, but the accuracy and precision of such results will decrease as the area surveyed increases in size. （小范圍內(nèi)，平面測(cè)量方法可以獲得精確的結(jié)果，但是隨著范圍的擴(kuò)大，精度和準(zhǔn)確度將隨之下降） For example, the length of an arc 18.5 km long lying in the earths surface is only 7mm greater than the subtended chord and, further, the difference between the sum of the angles in a plane triangle and the sum of those in a spherical triangle is 2 only 0.51 second for a triangle at the earths surface having an area of 100km . （例如，地球表面一條 18.5km 長(zhǎng)的弧只比其所對(duì)的弦長(zhǎng) 7mm，further，在一個(gè)面積為 100 平方公里的平面三角形中的內(nèi)角和與對(duì)應(yīng)球面三角形中的內(nèi)角和之差只有 0.51 秒） It will be appreciated that the curvature of the earth must be taken into consideration only in precise surveys of large areas.（只有在大面積的精密測(cè)量工作中地球曲率才必需被考慮）。 A great number of surveys are of the plane surveying type.（多數(shù)的測(cè)量工作都是屬于平面測(cè)量類型） Surveys for the location and construction of highways, railroads, canals, and in general, the surveys necessary for the works of human being