新大地坐标数据管理系统的开发毕业论文外文翻译.doc

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1、附录A:外文文献Development of new geodetic coordinate datum management systemAbstract：Current situations of geodetic coordinate datum development procedures and China were presentedThe precisions of astronomic geodetic network and space geodetionGeodetic datum requirements under the current and future new

2、surveying technologies and their applications were discussedThe necessity for upgrading national astronomic geodetic network and development of a new open coordinate geodetic datum management method was investigatedKey words：Geodetic Datum；Geodetic Network；ManagementINTRODUCTION Coordinates are the

3、reference for surveying and mappingThe development for a high quality coordinate datum is one of the important tasks for surveyors over the world and also a reflection to the survey technologies in stateCurrently，World Geodetic System 1984(WGS-84)is the most popularly used coordinate system internat

4、ionallyThere are two nationally used coordinate system，in 1954 Beijing system and 1980 Xian systernThere are lots of local coordinate systems developed with different methods in some areasConsidering the importance of coordinate system，a high quality coordinate datum with modern management method is

5、 essential1、GEODETIC COORDINATE SYSTEM STATUSIN CHINAAt the beginning when founding our stateformer Soviet Union Krasovskys ellipsoid was used for the development of reference coordinate systemThe origin of this system was in former Soviet UnionThe iointly surveyed coordinates of former Soviet Union

6、 geodetic coordinate network and the three points at Huma，Jilalin，and Dongning in Northeast of our country were taken as our astronomic starting reference dataThen a point in Beijing was calculated accordingly and was so called 1954 Beijing coordinate systemSince the founding of the state，a lot of s

7、urveying and mapping tasks were completed with this coordinate system despite some problems existed due to the technological restrictions at that timeThese prob1ems are：（1）The reference ellipsoid semi-major axis is more than 100m longer than modern precisely surveyed size （2）The reference ellipsoid

8、used is not identicall with the geoid of our counterThe elevation abnormity in Eastern is as high as 68 m （3）The ellipsoid reference axis direction is not precisely defined （4）Error accumulations are large and accuracy is lowTo overcome these problems and provide better services for economic develop

9、ment，national defence，and geodesy as well as space research，the National Surveying Bureau did adjust in one cast to national astronomic geodetic network in the end of 1970s and the beginning of 1980sThe 1980 Xian coordinate system was developedIUGG-75 ellipsoid was used in this systemThe difference

10、between ellipsoid and geoid is within 4-20 m and the side accuracy is 1/500 000 after adjustmentA new geodetic coordinate system is planning to meet the scientific needs in our country as the developments of new technologies such as very long base interfere(VLBI)and global positioning Systems(GPS)Th

11、e classes A and B GPS network were completed and put in use respective in 1996 and 1997The space geodetic network developments entered a new phase with these progressesIt is not only with higher accuracy than former systems but also with three dimension coordinates which developed on internationaly

12、defined ITRF frameThis high accuracy 3D space geodetic coordinate system will guarantee the infrastructure surveying for the first 10 years of twenty-first eenturyAfter adjustment，the plate coordinate overlap accuracy of class A GPS network is better than 210。Elevation accuracy is better than 710Abs

13、olute accuracy is better than 41.2 mFor class B network，these accuracies are better than 410，810，and 1 m，respectivelyThe completion of national class A and class B geodetic control network indicates that we have developed decimetre absolute 3D geodetic control net workA new reference system is avail

14、able for our space technology，and spatial data as well as real Proceedings of ISM 12th International Congress time dynamic positioningA lot of local coordinate systems were developed besides national plane coordinate systemThese systems served national economic developments in some senseConsidering

15、the importance of coordinate system to economic developments and national defence，coordinate system factors are confidential dataThe national and local governments control the geodetic coordinate factors strictly and data processing is also charged by relative government agencies2 MODERN SURVEYING T

16、ECHNOLOGY REQUIREMENTS FOR COORDINATE SYSTEM MANAGEMENTRequirements with advances and applications Of GPS GPS has been playing an important role in surveying and mapping from 1990 s and the accuracy is getting betterThe US GPS real time positioning accuracy is 3 mAs a military targeted system，SA was

17、 carried out on the beginning of GPS system and was removed on May 2000 to meet its economic benefitsThe US government provides higher accuracy of 30 m from earlier 100 m total standard usersA new Global Navigation Satellite System(GNSS)was in March 26，2002 by European Union(EU)to meet their own ben

18、efitsGalileo is a program independent of US GPS developed by EUAccording to its plan，Galileo program will include 30 satellites with four phasesThe first phase is system evaluation period(completed in 2000)；the second phase is development and test period(from 2001 to 2005)；the third phase is impleme

19、ntation period(2006 to 2007)；and the fourth phase is commercial operation perod(from 2008)The characteristics of Galileo are its civil purpose and high accuracyFree of chargeusers can reach6 m and charge users1 m which means an accuracy of 1 m global satellite positioning system will be available in

20、 2008The popularly used coordinate systems now in our country are 1954 Beijing system and 1980Xian system and 10cal systems are also based on these two systemsNational coordinate system is actually national astronomic geodetic networkThe national geodetic control point accuracy is far from the accur

21、acy of l m due to the restrictions of technologiesSo it is urgent to upgrade our astronomic geodetic network with modern surveying technologiesThe popularity and applications of global satellite require open coordinate management systemFor the historic reason，coordinate management in many areas in o

22、ur country is still with restriction and coordinate factors are confidential dataIt is not available for standard usersCoordinate transferring to control points takes in charge by government agenciesThe most distinctive character of GNSS is its real time positioning and navigationCurrently，real time

23、 kinetic(RTK)surveying requires coordinate factors for data processing in teal timePost processing can not meet the need of this technologyGNSS is not only single point coordinate surveyingThe integration of GPS and GIS is becoming a trendData collected by GPS receivers integrated with GIS includes

24、not only coordinates，but also graphs，attributes，topologies，etcThese functions can not be completed with solo point coordinate transferringThe development of open transferring factors between national coordinate system and GNSSespecially open local coordinate factor to public is essential with the ad

25、vances of GNSSRequirements of modern geographic information industry.As a key point of national economic development，the influence of modern geographic information industry has been growing greatlyAs a benchmark digital earth representing modern geographic technologies become the trend of informatio

26、n society，and the objective of digital earth is realizing the integration of economy and society information in the best way and promoting the information for society sharing and wide applicationWith the advances of every kind technology，nationwide and 10cal area government，enterprise，and different

27、thematic GIS development is getting fastThe development and applications of these systems bring great changes to government and economic managementCoordinate system datum is the basis of data collection and processing for all GISFor different reasons，there are different coordinate systems existing c

28、urrently in our countryThis requires that GIS software has the functionality of coordinate transferring in timeTransferring factors between different systems are essentialTraditional closed coordinate management mechanism can not meet the needs of GIS developmentsThe development of information shari

29、ng mechanism is the only way for digital earth technologyThe final objective is to promote digital earth development，enhance government agency corporation，avoid overlap development，and get high productivityThe information resource standardization is a guarantee for digital earth development and oper

30、ationThe transferring factors between different coordinate systems are important contents of standardizationIt is a precondition for data sharingProceedings of ISM12th International Congress3、DEVELOPMENT OF OPEN COORDINATE MANAGEMENT SYSTEMUpgrade national astronomic geodetic network coordinate syst

31、emWith the restrictions of technologies，the traditionaI main technology factor to evaluate 8n astronomic geodetic network is relative accuracyAbsolute accuracy is rarely usedAs the advances of GNSS。common users can get the accuracy of1 mThe current national astronomic geodetic network accuracy is lo

32、wer than1 mIt is an urgent task to promote current national astronomic geodetic network accuracyThe national GPS class A and class B network has been developedThere are 27 points for class A network and more than 700 points for class B networkThe point absoluteaccuracies of class A and class B netwo

33、rk are0.2m and41 m respectivelySide lengths are 650 km and 150 km respectivelyThis high density and accuracy space geodetic network can be used as known condition for the national astronomic geodetic network adjustmentThe current national astronomic geodetic network will be upgraded after data proce

34、ssingFor many reasons，there exists a lot of local coordinate systemsThe main reasons for these local systems are，firstly，on the beginning of state founding，national astronomic geodetic network had not covered all the nation due to technology restrictionsLocal coordinates were built to meet the needs

35、 of economic developmentsAs the completion of national astronomic geodetic network，these independent local systems were Iointly surveyed and transferring relations were built upSecondly。side transferring distortion was required 1ess than 1/40 000 due to technology consideringThirdly，national defence

36、 considerations，transferring factors between 10cal coordinate systems and national datum are confidentialThe transferring tasks must be completed through govern agenciesThese kinds of 10cal systems are widely usedFourthlvfor the reasons of local benefits，there exists several coordinate systems in th

37、e same areaThey are independent of each other and of no conneetionIt is obvious that local system played important role in the historyWith the advances of new technology，local systems blocked the new technology development and GIS can not share graphic applicationsThematicdataGPS real time nayigatio

38、n is an impossible missionIntegrated GIS and GPS receivers can not be used for data collection under local systemsThe only choices for those new technology and equipment users are，first，not using them and selecting other systems，and second，using the common points to calculate those factorsThis resul

39、ted in many different unstandardized factorsUnder the new society and technological conditions，new ideas should be introduced into the coordinate management agenciesLocal system is reasonable technically but close-in management is worth discussingNational defence iS one of the maln reasons for close

40、-in managementWith the advonces of modern technology，calculation of relationship between systems is not a difficult issueSo it is not realistic to use close-in management with those coordinate systems for national defence safetyIt is also responsibility for those surveying agencies to provide coordi

41、nate factors and make progress of new surveying technology applications附录B:中文翻译新大地坐标数据管理系统的开发摘要:大地坐标基准开发进行的现状在中国也存在。近些年,我们就大地基准的应用,以及在当代和未来的新测量技术的发展下开发大地基准进行了讨论。同时对升级国家天文大地网,开发新型的开放式大地坐标基准管理方法的必要性进行了研究。关键词:大地基准,大地网,管理1 简介坐标是测绘学中的参考。高质量坐标基准的开发不仅是世界各地勘测员的重要工作之一,也是一个国家测量技术水平的反映。目前,WGS-84(世界大地坐标系)是在国际上使

42、用最广泛的坐标系。1954北京坐标系和1980西安坐标系是我们使用的两个国家坐标系。依据不同的方法,在一些地区也开发出了许多地方坐标系。考虑到坐标系的重要性,开发出一个具有现代管理方法的高质量坐标基准是非常必要的。1中国大地坐标系统的概况在建国初期,前苏联的克拉索夫斯基椭球被用来发展参考坐标系。这个坐标系的坐标原点是前苏联。参加者调查了前苏联大地坐标网中的坐标系,在我们国家东北呼玛,基拉林,东宁的三点被用来作为天文起始的参考点。之后,有一点在北京被计算出来,据此,我们称之为1954北京坐标系。自从建国以来,通过这个坐标系,我们完成了许多测绘工作,但是由于当时技术的限制,也或多或少存在一些问题。

43、这些问题为:(1)参考椭球的半长轴尺寸要比现在精确测量的长100m。(2)所采用的参考椭球与我们计算出的大地水准面并不完全符合。东部高差达到正负68m。(3)参考椭球的轴向并没有明确定义。(4)累积误差大,精度小。 为了克服这些问题,为我们的经济发展、国防建设、大地测量学以及空间研究提供更好的服务,国家测绘局在70年代末80年代初对国家天文大地网的一个铸型做了校正。然后,1980西安坐标系就被开发出来了。这个坐标系以IUGG-75椭球作为参考。校正后，椭球和大地水准面的误差在4-20m范围内，面精度为1/500000。作为新技术的开发,我们国家正在设计一个新的大地坐标系来满足科学发展的需求,比

44、如说:VLBI(甚长基线干涉测量技术)和GPS(全球定位系统)。A、B类GPS网分别在1996、1997年建成并投入使用。伴随着这些进展,空间大地网的发展进入了一个崭新的阶段。它不仅较先前的系统精确度高,而且发展出了三维坐标,在国际发展上被定义为ITRF(国际地球参考框架)框架。这种高精度3D空间大地坐标系将担保21世纪头十年测绘工作的顺利进行。经过校正,A类GPS网的重叠精度优于210。高度精度优于710。绝对精度优于41.2m。对于B类网，这几个精度分别要优于410、810、1m。国家A类和B类大地测量控制网的建成说明我们已经开发出了分米精度级别的绝对3D大地测量控制网。新的参考系统对于我

45、们的航天技术的发展、空间数据的收集、甚至ISM（美国供应管理协会）第十二届国际会议上真是行为的实时动态定位都是可用的。除了国家平面坐标系统,也开发出来许多地方坐标系统。从某种意义上来说,这些系统在为国家的经济发展服务着。考虑到坐标系对于国家经济发展和国防安全的重要性,坐标系因子都是绝密数据。国家和地方政府严格控制大地坐标因子,而且数据处理也必须是有相关的政府机构负责。2 坐标系统管理的现代测绘要求从20世纪90年代起,GPS研究进展和应用要求一直在测绘学中扮演着重要的角色,而且精度也越来越高。美国GPS的实时定位精度为3 m。作为一个军事目的系统,SA(选择可用性,美国采取的限制定位精度的政策

46、)在GPS开发初期就开始执行,但是为了满足他们的经济效益,在2000年5月份这个政策被废除。美国政府向所有普通用户提供较之前精度100m更高的精度30m。欧盟为了满足他们的利益,在2002年3月26日将一个新型的全球卫星导航系统初始化。Galileo就是由欧盟开发的一个独立于美国GPS的程序。根据它的计划,Galileo包括30个卫星,分为4个阶段。第一阶段时系统评价阶段(2000年完成);第二阶段是发展和测试阶段(2001-2005年);第三阶段是实施阶段(2006-2007年);第四阶段是商业运行阶段。Galileo的特点是它的民用性和高精度。免费用户精度能达到6m,收费用户精度能达到1m

47、,这意味着精度为1m的全球卫星定位系统在2008年将能够投入使用。现在在我们国家被广泛使用的坐标系是1954北京坐标系和1980西安坐标系,地方坐标系也是建立在这两个系统之上。国家坐标系实际上是国家天文大地网。由于技术条件的限制,国家大地控制点的精度离1m的精度还差很远,所以,使用现代测绘技术,省级我们的天文大地网是十分迫切的。全球卫星的普及和应用需要开放的坐标管理系统。由于一些历史原因,我们国家许多地区的坐标管理仍然受到限制,而且我们坐标系的因子都是绝密数据。对于一般用户来说是不可用的。政府机构负责将坐标系转换为控制点。GNSS最鲜明的特点是它的实时定位和导航。目前,实时动态差分(RTK)测

48、量需要坐标因子来进行实时数据处理,后处理不能够满足这种技术要求。GNSS不仅仅是单点的坐标测量。GPS和GIS的集成已经成为一种趋势。GPS与GIS集成接收器收集的数据不仅包括坐标,还有图片,属性,拓扑结构等等。这些功能不能完成单独点的坐标转化。国家坐标系统和GNSS的开放转换因子的发展，尤其是将GNSS地方坐标因子开放给公众是必要的。现代地理信息产业的要求作为国经济发展的一个关键点,现在地理信息产业的影响越来越大。作为代表现代地理技术的参照,数字地球已经成为信息和社会的一种趋势。数字地球的目标是以最好的方式实现社会经济和信息的一体化,促进信息的社会共享与广泛应用。随着各种技术的发展,国家和部分地方的机构、企业以及不同的专项地理信息系统的发展也越来越快。这些系统的发展和应用给我们政府和经济管理也带来了很大的改变。坐标系统的点是所有GIS数据采集和处理的基础。由于各种各样的原因,现在在我们国家还存在着一些不同的坐标系统。这就要求GIS软件具有即时坐标转化的功能。不同系统之间的转换因子也是必不可少的。传统的封闭式的坐标管理机制并不能满足GIS发展的需求。信息共享机制的发展是开发数字地球技术的唯一途径。其最终目的是促进数字地球的发展,增加政府代理团体,避免重复发展并获得高生产率。信息资源标准化是数字地球发展和运行的保障,不同坐标系统之间的转换因子是标准化的重要内容