Standards and Guidelines for Cadastral Surveys Using Global Positioning Methods
Dr. Michael D. Londe, USA
Key words: GPS, Standards, Cadastral Surveys.
ABSTRACT
The development of high production GPS methods such as kinematic real time kinematic (RTK) , and fast static procedures have given rise to questions as to what are acceptable procedures for conducting cadastral surveys. This is due to the fact that these methods are radial survey methods. There are many standards and specifications that address how control surveys should be performed and to what accuracies but non that address acceptable procedures for the survey itself.
A team of U.S. Dept. Of Interior – Bureau of Land Management (BLM) and U.S. Department of Agriculture – Forest Service (FS) surveyors and geodesists have developed a new document titled Standards and Guidelines for Cadastral Surveys Using Global Positioning Methods (GPS Standards and Guidelines) to provide guidance to the cadastral surveyor in using GPS to conduct surveys. This document was developed from a combination of practical field procedures developed by team members, manufacturer guidelines, examination and review of existing standards and specifications, and review by government and private sector land surveyors. These Standards and Guidelines give an accuracy standard that are compatible with existing conventional survey methods and are easily achieved with current equipment. They are also in agreement with standards specified by the U.S. Federal Geodetic Control Committee (FGDC). Measurements are made by first establishing a project control network and then making corner measurements relative to this network. The rocedures can be used with setups of two or more receivers.
Standards and Guidelines for Cadastral Surveys Using Global Positioning
Methods
Dr. Michael D. Londe, USA
1. INTRODUCTION
The adoption of high production GPS techniques is changing how large scale cadastral surveys are performed. While the plats and field notes still constitute the basic returns and records; the use of GPS is changing how the surveys are conducted in the field, how the returns are being computed, and how the accuracy of the data and survey is evaluated.
For over 200 years the basic field procedures have changed very little. Originally lines were run using a solar compass and Gunter’s chain. This later gave way to solar observations and angulation using transits and chain or electonic total stations. Lines wererun corner to corner and returns computed by direct measurement along true lines or inverses based on summation of latitudes and departures along random lines. Data quality was evaluated by the closure of travers loops around closed figures. These are techniques famliar to all surveyors.
The use of GPS has changed the ways surveys are conducted. GPS can be used in the same way as electonic total stations and direct measurements made between corners and returns directly computed from the observed baselines. It can also be used in a modified radial or network scheme to establish point positions relative to a control network and returns computed from inversing between corner positions. No longer is it necessary to measure directly corner to corner.
However with these new abilities have come new questions. What are acceptable field procedures? How do we evaluate data quality. Do we need ties and how many to ingle or multiple control points if radial techniques are used? These questions can be confusing to both the novice and expert user of GPS.
Many standards and specifications exist for the establish of geodetic control networks using GPS. However there are not any guidelines or standards that deal explic itly with production surveys. The FS and BLM have sought to provide guidance to their cadastral surveyors by jointly developing a set of accuracy standards and procederal guidelines that provide a set of minimally acceptable proceduresfor using GPS. By following these guidelines the new GPS surveyor can be assured of performing defensible surveys while the experienced user has set of accuracy standards and procederal guidelines which they can then use or modify as necesary to accommodate local practice or project needs.
This paper will provide a brief history of the development of the GPS Standards and Guidelines, their history, philosophy, and important aspects of their use.
2. HISTORY
The BLM and FS started to use GPS with the introduction of the first portable systems in the late 1980s. These initial efforts were mainly to make geodetic ties to conventional surveys, establishing project control networks, or running corner control orver long distances. During this time many surveyors started to explore the possibilities of using GPS as a production survey tool. Many field tests were run using a variety of observational schemes including direct measurements from corner to corner, fully networked observations, and modified radial observation schemes. A common thread was that all of the observation methods were static based and procedures were based on the specifications for creation of geodetic control networks. The results were mixed. The number of receivers, personnel requirred, and the length of observations required seemed to limit
the utility of GPS to conduct surveys
With the advent of observational techniques such as kinematic, fast static, and especially RTK GPS the surveyor now had tools that could allow him or her to survey more points in less time. As more field tests were performed, many questions came up as to how the surveys should be performed. Many of the questions seemed to center on whether the observational requirements of geodetic control surveys should be followed or used or whether a lesser but still rigorous system could be used .
During this period Region Two of the FS (Colorado, Wyoming, South Dakota, and Nebraska) and the Wyoming BLM were among the most active in evaluating these new methods and developing the use of Fast Static and RTK GPS for cadastral surveys. The GPS leads for the two agencies often collaborated on projects to test new data collection procedures and shared information and thoughts regarding accuracy requirements, redundancy, observation times, control ties, and data evaluation needs. It was jointly recognized that different standards would be needed for GPS to become a high production survey tool.
During these discussions the GPS Leads for the FS Region Two and the Wyoming BLM had produced draft accuracy standards and procedural guidelines for use by surveyors and contractors in their respective region and state. These guidelines were based on personal experience and experimentation as well as reliance on the work of other surveyors and established standards and specifications. Continued discussions and joint projects brought about the recognition that since both agencies were performing the same type of surveys they should try formulate and use similar methods and procedures. At this time the leads started to merge their seperate documents into one that would cover the use of GPS for cadastral surveying in their region.
During the late 1990s the BLM and FS both started to widely implement GPS surveying based on RTK GPS use. Across the agencies the questions on how to use GPS wre being heard more and more. In 1998 a joint team of FS and BLM surveyors and geodesists was created for the task of developing a single set of GPS accuracy standards and guidelines that would guide the use of GPS for the respective agencies. The draft guidelines that had been developed by the FS in Region Two and the Wyoming BLM became the core of this new document. During the course of the next three years the philosophy, text, and procedures were repeatedly ( and sometimes heatedly) discussed, reviewed, and modified as new material was examined and technology was changing. Additional reviews were sought from both the government survey and private community. Especially helpful were reviews The final document was submitted to the respective Washington offices of the BLM and FS in March 2002 and issued on joint letterhead in July 2002 with the note that as we move to a fully integrated federal, state, local, and private mapping and land record system, there should be government wide standards and guidelines for using GPS technology on cadastral surveys of the public and Indian lands.
3. PHILOSOPHY
Several philosophies and viewpoints are central to the GPS Standards and Guidelines and their use. These philosophies affect both the accuracy standards and the data collection procedures. Much of the discussion and many of the procedures are aimed at the use of RTK GPS since it is the method of choice but the document is applicable to all data collection procedures.
The basis of the data collection scheme is through the use of modified radial survey techniques. This holds for both RTK or fast static based data collection. The use of a project control network is necessary to support these types of observations and provide for possible
checks and efficiency in data collection. A primary consideration is to be able to support the two receiver RTK system as well as multi-receiver data collection. Data evaluation is based on point accuracies as opposed to loop closures. This is necessary given the radial nature of the data collection and non networked or lack of direct corner to corner measurements. The point accuracy can be derived from least squares analysis, weighted mean position averages, or considerations of the control point accuracy and manufacturer specifications. The accuracy standards are designed such that bearings andm distances obtained from inversing between corner positions will be the equal or better than thos eobtained from conventional surveys.
The GPS Standards and Guidelines need to be flexible and modifications allowed to accomodate local practice and surveyor preference. They shoud be viewed as the minimum procedures that should be followed in using GPS to do cadastral surveys. In the same mannerthey should be applicable to multi-township sized surveys or one section subdivisions. While designed with RTK data collection in mind , they can also cover fast static or kinematic collection.
The GPS Standards and Guidelines had to be surveyor and production oriented. The
document had to be understandable by both the beginning and experienced GPS surveyor. A central view is that the projects do not constitute geodetic control work and that it is not necessary the field and observation procedures to be as stringent and still be able to achieve accurate results. Lastly the document needed to fulfill a multifunctional role. Besides giving direction to surveyors using GPS, it also needed to be a teaching document covering basics of data collection and project control design. It also needed to be a document that spelling out requirements for contractors or cooperators submitting data to the respective agencies. These demands account for the structure and content of the work.
4. IMPORT ANT POINTS
This section of the paper will discuss in more detail some of the points outlined in the above sections that are integral to successful application of the GPS Standards and Guidelines. Every possible data collection scheme or check for RTK GPS and the other collection methods have not been listed or described in the document. The methods and procedures that are discussed are intended to be guidelines to what could constitute good practice. The flexibility built into the guidelines allow the surveyor to develop and apply data collection methods and checks that are harmonious with the documents.
The positional accuracy standards shown below in Tables One and Two are based on data analysis and manufacturer specifications. They reference the positional accuracy of the points relative to external control.
T able1 .Local accuracy standards
Local Accuracy 95%Confidence Circle Application
0.050 meters Less Than 0.050m Cadastral Project Control
0.100 meters Less Than 0.100m Cadastral Measurements Local Accuracy is an average measure (e.g. mean, median, etc.) of the relative accuracies of the coordinates for a point with respect to other adjacent points at the 95% confidence level.
T able2. Network accuracy standards
Local Accuracy 95%Confidence Circle Application
0.100 meters Less Than 0.100m Cadastral Project Control
0.200 meters Less Than 0.200m Cadastral Measurements
The Network Accuracy of all Cadastral Measurements should be reported per the Federal Geographic Data Committee (FGDC) Geospatial Positioning Accuracy Standards to show the relationship of the cadastral survey relative to the National Spatial Reference System.
This requires that the local accuracy of the Cadastral Project Control should be less than 5 cm 95 % of the time. The Cadastral Measurements should then have a maximum relative accuracy relative to the project control of 5 cm . This results in the overall 10 cm (95% confidence) shown in Table One.
These values are used so that bearings and distances returned from inverses between corner positions will be as good or better than that of conventional surveys.
The accuracy bands are also set up to be in accordance with FGDC Geospatial Positioning Standards. This is to be consistent with developing federal guidelines and metadata development. Project Control Networks are central to the application of the GPS Standards and Guidelines. The project networks could be as small as two points for small projects or number as many as four or more for large township sized projects. The number of points will depend on a number of factors such as as access, topography, minimizing baseline lengths when possible, opportunities for checks, and spacing necessary for efficient operations. Project Control Networks are not intended to be densifications of the National Spatial Reference System (NSRS). However good observation practices such as ties to two or more high accuracy NSRS stations, multiple point occupations, good network design, and adjustment to obtaining high quality control. This is vital since the Project Control Network is the framework that holds the project together and allows observations, such as RTK, based on two receiver systems to work.
GPS surveying in the FS and BLM is built around two receiver systems. The predominant Cadastral Measurement data collection method is by RTK GPS. The a major concern is providing sufficient redundant measurements at a corner position. Traditionally one would tie a point to two separate control points. However this is sometimes not practical due to point access, terrain problems, or other considerations. The GPS Standards and Guidelines accepts multiple measurements to a single control point as checks. In the case of RTK GPS loss of satellite lock and reinitialization between measureents is required regardless of time or distance seperation. Additional checks (based on changing the observation environment) such as waiting a specified period time, reinitializing in a different location, or changing the antenna height could be integrated. Testing has shown that this is a viable technique when used with a well design Project Control Network. Even though there is not a required redundancy factor built into the GPS Standards and Guidelines, the user is encouraged to check points by observations relative to different control points.
5. SUMMARY
The GPS Standards and Guidelines is intended to provide guidance to the surveyor using GPS to perform Cadastral or other types of boundary surveys. In a short time this document has gained wide circulation and acceptance. Copies of draft and the final versions have been requested by other federal agencies, state and local government groups, GPS equipment manufacturers. and
private surveyors and organizations in the United States and overseas.
6. ACKNOWLEDGEMENTS
The author would like to acknowledge the co-authors of the Standards and Guidelines for Cadastral Surveys Using Global Positioning Methods : Carl Sumpter (Region Two, FS) and Ken Chamberlain (Region 6, FS) and Ken Bays of the Oregon BLM. I would like to also acknowledge Tom Effinger (FS), Ignacio Lopez (formerly of the California BLM), and Dave Doyle( National Geodetic Survey) for their contributions. Thanks are also due to Dale Wilson, Dan Schank, and Dennis Milbert for their comments and reviews.
REFERENCES
Analysis of Real-Time Kinematic and Fast Static/Kinematic Least Squares Derived Coordinates Using a Wisconsin County UDN@; Paul Hartzheim and Darin Henkel,
Wisconsin Department of Transportation, Trimble User Conference Proceedings, 1998. Accuracy Standards for Positioning@, V ersion 1.0 (DRAFT) July 1996, Natural Resources Canada-Geodetic Survey Division.
Geometric Geodetic Accuracy Standards and Specifications for Using GPS Positioning Techniques@, V ersion 5.0, May 11, 1988, reprinted with minor corrections August 1,
1989, Federal Geodetic Control Committee.
Geospatial Positioning Accuracy Standards@, FGDC-STD-007-1998, Federal Geographic
Data Committee.
New Mexico State Office Accuracy Standards for Cadastral Surveys@, New Mexico State Office, U.S. Bureau of Land Management.
Standards and Guidelines for Cadastral Surveys Using Global Positioning System Methods”,
V1.0, May 9, 2001, BLM I.M. 2001-186.
Utilizing Real-Time Kinematic GPS for Control Surveys@, Ronald Berg, Ministry of Transportation, Ontario, Trimble User Conference Proceedings, 1998.
BIOGRAPHICAL NOTES
Dr. Michael D. Londe is a Geodesist with Wyoming BLM in the United States for the last
10 years. He has been involved with GPS instruction, implementation, field surveying and mapping, and testing since 1987.
使用GPS方法进行地籍调查的标准和准则
关键词：GPS，标准，地籍调查
摘要
高生产的GPS的发展，如实时动态（RTK技术），快速静态程序使“什么是可接受的地籍调查？”这一问题得到提出。这些方法是径向调查方法，有许多标准和规范，解决了控制测量应如何被进行，以及何种精度，但非对于调查本身的程序。美国内政土地管理局（BLM）和美国农业部-林务局测量师和geodesists已经提出一种新方法，标题为地籍调查使用全球定位标准与准则方法（GPS标准与准
则），以供测量师利用GPS进行调查进行指导。此方法是由现役测量员与制造商以现有准则为蓝本，经国有及私有测量师审查后提出。此文件有与现存常规方法兼容，现有设备易实现等特点，同时与美国FGDC（美国测量控制委员会）所指定的标准一致。测量是由先建立控制网络，然后再进行角测量。该程序可用于两个或多个接收设置。
1. 介绍
采用高生产GPS技术正在改变地籍调查是如何进行大规模。而植物和专业笔记仍然构成基本报税及记录; 全球定位系统(GPS)的使用正在发生变化,对是如何在田野调查、是如何开展的回报以及如何计算数据的准确性和问卷调查的方法进行了评价。 200多年来，基本论域程序已经改变了很少。这后来又让位给了太阳能的观察和倾斜角度的运行和链或使用电子总站。线都跑角落到角落并返回计算沿真实线路或直接测量的基础上,总结逆纬度和离开沿着随机线。数据质量是评价周围的关闭回路数字。所有这些都是熟悉的测量技术全球定位系统(GPS)的使用已经改变了这种被管理的调查方式。全球定位系统可以用于同样的方式为电子总站和直接测量角及回报之间制造的直接计算从观测基线。还可用于一种改进的径向或网方案建立点位置相对于控制网络,并返回计算从逆变角位置之间。不再认为有必要直接测得的各个角落。然而这些新的能力同时带来了一些新的问题。什么是可接受的现场手续?我们队如何评估数据质量控制进行了探讨。如果径向技术在使用中，我们需要联系多少单个或多个控制点?这些问题一直困扰所有使用GPS的新手和专家用户。许多标准以及规格是为了那些使用GPS建立的大地控制网而存在的。但是没有任何明确的指导方针、标准以及成果调查。FS和BLM已经通过共同开发一套精度标准和程序指南以及提供一套利用GPS最小可接受的程序来寻求指导他们的地籍测量师的指南方针,。遵循这些指南，新的GPS 测量员的测量才能保证稳固的调查，而有经验的用户已建立的准确性的标准和程序指南,然后他们进行的使用或修改是适应当地的实践或项目需求所必要的。本文将提供一个短暂的历史发展的GPS标准和指南,他们的历史、哲学作为重要方面之一供其使用。
2、历史由来
国土管理局与FS开始使用引进了易传性系统的GPS，是在十九世纪八十年
代末。
最初的目的是使测地学更紧密联系与传统的勘察，实现网络控制化，或者是远距离进行角落的测量。这些年来，许多勘察家已经把GPS作为是一种测量工具。很多的土地测试都用了许多的观察方案，包括对角线测量，网络测量，以及改良的射线测量方法。他们共同的思路是，所有的这些方法都是静止的，过程都是在测量学网络操控的主要技术参数的基础上进行的。得出的结果是混合性的。接收者的数据，工作者的要求，观测的长度要求，这些因素似乎都限制了GPS对测量的控制指导。
随着观测技术上出现诸如动态、快速静态,尤其是GPS RTK测量技术，测量员拥有工具可以允许他们在更少的时间内测量更多的点。随着越来越多现场试验的进行，测量方法上的很多问题都暴露出来了。许多问题看起来是以大地控制测量的观测要求是否服从或者习惯于较少缺要求严格的系统为中心。
在这段时期的地区里, FS(科罗拉多,怀俄明,南达科他和内布拉斯加州)和
怀俄明BLM这两家机构是最活跃于评估这些新方法以及发展利用静态和GPS RTK
方法进行地籍调查。GPS引导这两家机构经常合作完成项目以测试新的数据采集程序、共享对于精度要求、冗余、观察次,控制关系,和数据评价的需要的信息和思想。共同认识到的是，为GPS提供不同的精度标准使其成为高生产率的测量工具。
在这些讨论中，GPS引导FS地区和怀俄明BLM机构，对起草用于测量师和承包商在他们各自的地区和国家产生了准确性的标准和程序指南。这些指南在基于个人的经验和实验以及依赖其它设备的工作上,建立了测量的标准和规范。继续进行讨论和参加项目带来了一些识别，自从两大机构进行了同一类型的调查，他们应该制定和使用类似的方法和程序。在这个时候，引导者开始合并他们一些为地籍测量他们所在区域的GPS文档记载。
在20世纪90年代末,BLM和FS都开始广泛实施基于RTK全球定位系统的GPS 测量使用。在整个机构中听到越来越多的问题是如何使用GPS。在1998年创建了一个由FS和BLM测量员以及测量技师组成的联合小组，任务是创造发展一套单一的将为各自的机构指导GPS使用的GPS精度标准和指导方针。该草案指南是由区域Two的FS和怀俄明州的BLM发展而成并成为新文件的核心。在此过程中,
未来三年内的哲学、文本和程序被再三(有时甚至热烈)讨论、检查和修改,并作为一种新型材料进行了研究,技术开始改变。分别从政府调查和私人社区寻求额外的综述。尤其有益的是由国家大地测量提供的检查。最后的文件在2002年3月被提交到BLM和FS各自的华盛顿的办公室,于2002年7月发行在共有的信笺，包含注解：当我们搬到一个完全整合联邦、州、地方,以及私人映射和土地记录系统的地方,在公众的印地安人的土地地籍调查上使用GPS技术应该有政府宽的标准和指导方针。
3、基本原理
几个基本原理的中心观点和看法对于GPS的使用标准以及指导方针是极其重要的。这些基本原理影响了精度标准以及数据采集程序。许多的的讨论以及程序是以利用GPS RTK为目的的，因为它是一种文件适用于所有的数据收集程序的方法。
数据收集计划的基础是通过使用改性径向调查技术而达成的。这一规律同样适用于RTK或快速静态数据的收集。对于支持这些类型的意见，并提供可能的检查和数据收集的效率来说，一个项目的控制网络的使用是必要的。一个首要考虑的因素是能够支持两个RTK系统接收机以及多频接收器的数据收集。
数据评价是基于点的精度与循环闭合度的对照的。对径向性质的数据采集和非网络或缺乏直接的角落给予了到角落的测量结果是有必要的。点精度可源自最小二乘分析、加权平均位置平均数,或考虑的关键控制点的精度以及制造商的规格说明。准确度标准是这样设计的，轴承和角位置之间反演获得的将是等于或小于从传统的统计调查所得为佳距离。
GPS标准和指导方针也需要灵活修改改造，以适应当地的实践及测量员的偏好。他们应该被看作是GPS系统进行地籍调查时所应遵循的最低限差。同样的规范应该适用于多城镇大小或者小范围地区的的调查。当考虑设计RTK数据采集系统的时候，他们同样涵括了快速静态和动态的采集。
GPS标准和指导方针必须成为测量员和产品的指导方向。该文件必须一开始由一个富有经验的GPS测量员来进行理解。一个中央的观点认为,一项不构成大地控制工作的项目,是没有必要进行实地观察以及严格程序,也可以实现精确的结果。
最后，这个文件需要完成一种多功能的作用。除了提供测量员使用GPS的方法，它同样需要一个包括数据收集和项目控制设计基础的教学文件，以及一份能拼写出来的文件。
4 、重点
这一部分将会更加详细的探讨在前面的章节提到过的一些要点，这些部分对GPS的标准和指导原则的成功应用是必不可少的。每一种对RTK GPS进行数据收集的可能性方案或者检查方案，以及其他的数据收集方法目前还没有在文献中出现或讨论过。现在讨论的方法和步骤将会成为指导怎样才能延续进行好的实践的行为准则。在这些准则中的灵活性使得测量员可以发展和应用这些与文献相协调的数据收集方法和核对检查方法。
基于数据分析和厂家说明书建立的位置准确度的标准如下面表一和表二所示。他们引用了一些与外部控制相关的、位置准确度的要点。
表一，局部准确度标准
局部准确性95%的置信度应用
0.050m < 0.050m 地籍项目控制
0.100m < 0.100m 地籍测量
局部准确度是一种对某一要点的坐标系的相关精度的平均测量（如平均值，中间值等），而将其他相近的要点置于95%的置信水平。
表二，网络模式的准确度标准
局部准确性95%的置信度应用
0.100m < 0.100m 地籍项目控制
0.200m < 0.200m 地籍测量
所有地籍图测量的网络式精度都应该向每个联邦地理资料委员会(FGDC)报告实时的战场地理空间定位精度标准，说明地籍测量和公民空间参照系统之间的联系。
这个就要求地籍项目控制的局部精度应该少于5cm 95%的时间。地籍测量应该有一个相关精度的最大值，该值与5cm项目控制有关。这个导致了如表一所示
的总体精度10cm（95%的置信水平）。
这些价值被利用使得在从遥远地区逆向回馈的方位和距离，结果和常规的调研一样甚至更好。精度区的建立也是为了与FGDC 实时的战场地理空间定位精度标准相协调。这个将会与发展中的联邦准则和元数据发展一致。
项目控制网络对于GPS标准和准则的应用非常关键。这个项目网络可以小到针对小项目的两个要点，也可以针对大型镇区规模多到四个或者更多要点。要点的数量取决于很多因素，如进入通道、地形地貌、可能情况下极小化基准线长度、检测机会，和高效运作的必须间隔。项目控制网络并不是公民空间参照系统（NSRS）的浓缩。但是是好的观测实践，如连结两个或以上的高精度的NSRS站，多种要点的使用，良好的网络设计，和为获得更高质量的控制做出的调整。这点自从项目控制网络成为粘合各项目和进行观测的纲要之后变得十分重要，例如RTK，这个的运行要基于两个接收系统。
GPS测量在FS和BLM中都是基于两个接收系统建立的。最盛行的地籍测量数据收集方法是利用RTK GPS。一个主要的问题在于提供足够的多余的测量在一个边远的地点。传统意义上讲，我们应该将一个要点与两个独立的控制要点连结起来。但是有时候出于要点通道，地形困难，或者其他的考虑，这是不实际的。GPS标准和准则允许多样的测量对应一个单独的控制要点项目作为检测。而对于RTK GPS，无论时间或距离是否分离，测量之间的卫星锁定的丢失和重新初始化是必须的。额外的检测（基于改变的观测环境），如等待一个特别的时期，在不同的地方重新初始化，或改变天线高度可以完善该检测。试验表明，当和一个设计优良的项目控制网络联合使用时，这是一个切实可行的技术。尽管没有一个必须的备份的因素加入到GPS标准和准则中，但使用者还是被鼓励利用不同的控制点的观察值来检测各个要点。
5、概要
全球定位系统标准与准则的目的是提供指导验船师使用GPS来进行地籍边界的调查或其他类型的调查，在很短的时间本文件得到了广泛的流通和验收。草案的副本与最终版本已被其他的联邦机构，州和地方政府团体，在美国或海外的私人测量师还有GPS设备制造商所要求。
6、鸣谢
作者想要感谢合作作家的标准和指导方针为地籍概观使用全球定位方法:卡尔桑普特(地区二，采样频率)，县管家(地区6，采样频率)，县的海湾俄勒冈土地管理局。感谢汤姆安东尼(采样频率)，伊格纳西奥洛佩斯(以前的加利福尼亚土地管理局)，戴夫多伊尔(国民大地测量)为他们的贡献。谢谢戴尔威尔逊，担施克，丹尼斯扩音器查看联系方式为他们的评语，评论。
参考文献
分析实时动态和快速静态运动最派生方坐标使用威斯康星县联合报，保罗和达林汉高，美国威斯康星州交通局，特林布尔用户大会论文集，1998。
定位1.0版精度标准（草案）1996年7月，自然资源加拿大，大地测量部。
几何大地测量精度标准和利用GPS定位技术，版本5.0，1988年5月11日，1989年8月1日改正重印，联邦大地测量管制委员会规范。
地理空间定位精度的标准，FGDC - 007 - 1998，联邦委员会地理数据
新墨西哥州立厅地籍调查，新墨西哥州国办精度标准，美国土地管理局。
地籍管理的标准和使用全球定位系统方法调查，V1.0的标准，2001年5月9日，博莱霉素的IM 2001-186。
利用控制测量，罗纳德伯格，交通局，安大略省特林布尔用户大会论文集，1998年教育部实时动态GPS。
Load and Ultimate Moment of Prestressed Concrete Action Under Overload-Cracking Load It has been shown that a variation in the external load acting on a prestressed beam results in a change in the location of the pressure line for beams in the elastic range.This is a fundamental principle of prestressed construction.In a normal prestressed beam,this shift in the location of the pressure line continues at a relatively uniform rate,as the external load is increased,to the point where cracks develop in the tension fiber.After the cracking load has been exceeded,the rate of movement in the pressure line decreases as additional load is applied,and a significant increase in the stress in the prestressing tendon and the resultant concrete force begins to take place.This change in the action of the internal moment continues until all movement of the pressure line ceases.The moment caused by loads that are applied thereafter is offset entirely by a corresponding and proportional change in the internal forces,just as in reinforced-concrete construction.This fact,that the load in the elastic range and the plastic range is carried by actions that are fundamentally different,is very significant and renders strength computations essential for all designs in order to ensure that adequate safety factors exist.This is true even though the stresses in the elastic range may conform to a recognized elastic design criterion. It should be noted that the load deflection curve is close to a straight line up to the cracking load and that the curve becomes progressively more curved as the load is increased above the cracking load.The curvature of the load-deflection curve for loads over the cracking load is due to the change in the basic internal resisting moment action that counteracts the applied loads,as described above,as well as to plastic strains that begin to take place in the steel and the concrete when stressed to high levels. In some structures it may be essential that the flexural members remain crack free even under significant overloads.This may be due to the structures’being exposed to exceptionally corrosive atmospheres during their useful life.In designing prestressed members to be used in special structures of this type,it may be necessary to compute the load that causes cracking of the tensile flange,in order to ensure that adequate safety against cracking is provided by the design.The computation of the moment that will cause cracking is also necessary to ensure compliance with some design criteria. Many tests have demonstrated that the load-deflection curves of prestressed beams are approximately linear up to and slightly in excess of the load that causes the first cracks in the tensile flange.(The linearity is a function of the rate at which the load is applied.)For this reason,normal elastic-design relationships can be used in computing the cracking load by simply determining the load that results in a net tensile stress in the tensile flange(prestress minus the effects of the applied loads)that is equal to the tensile strength of the concrete.It is customary to assume that the flexural tensile strength of the concrete is equal to the modulus of rupture of the
外文翻译 原文 World Trade and International Trade Material Source:https://www.doczj.com/doc/b72530452.html, Author: Ted Alax In today’s complex economic world, neither individuals nor nations are self-sufficient. Nations have utilized different economic resources; people have developed different skills. This is the foundation of world trade and economic activity. As a result of this trade and activity, international finance and banking have evolved. For example, the United States is a major consumer of coffee, yet it does not have the climate to grow any or its own. Consequently, the United States must import coffee from countries (such as Brazil, Colombia and Guatemala) that grow coffee efficiently. On the other hand, the United States has large industrial plants capable of producing a variety of goods, such as chemicals and airplanes, which can be sold to nations that need them. If nations traded item for item, such as one automobile for 10,000 bags of coffee, foreign trade would be extremely cumbersome and restrictive. So instead of batter, which is trade of goods without an exchange of money, the United State receives money in payment for what it sells. It pays for Brazilian coffee with dollars, which Brazil can then use to buy wool from Australia, which in turn can buy textiles Great Britain, which can then buy tobacco from the United State. Foreign trade, the exchange of goods between nations, takes place for many reasons. The first, as mentioned above is that no nation has all of the commodities that it needs. Raw materials are scattered around the world. Large deposits of copper are mined in Peru and Zaire, diamonds are mined in South Africa and petroleum is recovered in the Middle East. Countries that do not have these resources within their own boundaries must buy from countries that export them. Foreign trade also occurs because a country often does not have enough of a particular item to meet its needs. Although the United States is a major producer of sugar, it consumes more than it can produce internally and thus must import sugar.
E---MARKETING (From:E--Marketing by Judy Strauss,Adel El--Ansary,Raymond Frost---3rd ed.1999 by Pearson Education pp .G4-G25.) As the growth of https://www.doczj.com/doc/b72530452.html, shows, some marketing principles never change.Markets always welcome an innovative new product, even in a crowded field of competitors ,as long as it provides customer value.Also,Google`s success shows that customers trust good brands and that well-crafted marketing mix strategies can be effective in helping newcomers enter crowded markets. Nevertheless, organizations are scrambling to determine how they can use information technology profitably and to understand what technology means for their business strategies. Marketers want to know which of their time-ested concepts will be enhanced by the Internet, databases,wireless mobile devices, and other technologies. The rapid growth of the Internet and subsequent bursting of the dot-com bubble has marketers wondering,"What next?" This article attempts to answer these questions through careful and systematic examination of successful e-mar-keting strategies in light of proven traditional marketing practices. （Sales Promotion;E--Marketing；Internet；Strategic Planning ） 1.What is E--Marketing E--Marketing is the application of a broad range of information technologies for: Transforming marketing strategies to create more customer value through more effective segmentation ,and positioning strategies；More efficiently planning and executing the conception, distribution promotion,and pricing of goods,services,and ideas;andCreating exchanges that satisfy individual consumer and organizational customers` objectives. This definition sounds a lot like the definition of traditional marketing. Another way to view it is that e-marketing is the result of information technology applied to traditional marketing. E-marketing affects traditional marketing in two ways. First,it increases efficiency in traditional marketing strategies.The transformation results in new business models that add customer value and/or increase company profitability.
forced concrete structure reinforced with an overviewRein Since the reform and opening up, with the national economy's rapid and sustained development of a reinforced concrete structure built, reinforced with the development of technology has been great. Therefore, to promote the use of advanced technology reinforced connecting to improve project quality and speed up the pace of construction, improve labor productivity, reduce costs, and is of great significance. Reinforced steel bars connecting technologies can be divided into two broad categories linking welding machinery and steel. There are six types of welding steel welding methods, and some apply to the prefabricated plant, and some apply to the construction site, some of both apply. There are three types of machinery commonly used reinforcement linking method primarily applicable to the construction site. Ways has its own characteristics and different application, and in the continuous development and improvement. In actual production, should be based on specific conditions of work, working environment and technical requirements, the choice of suitable methods to achieve the best overall efficiency. 1、steel mechanical link 1.1 radial squeeze link Will be a steel sleeve in two sets to the highly-reinforced Department with superhigh pressure hydraulic equipment (squeeze tongs) along steel sleeve radial squeeze steel casing, in squeezing out tongs squeeze pressure role of a steel sleeve plasticity deformation closely integrated with reinforced through reinforced steel sleeve and Wang Liang's Position will be two solid steel bars linked Characteristic: Connect intensity to be high, performance reliable, can bear high stress draw and pigeonhole the load and tired load repeatedly.
Journal of Industrial Textiles https://www.doczj.com/doc/b72530452.html,/ Optimization of Parameters for the Production of Needlepunched Nonwoven Geotextiles Amit Rawal, Subhash Anand and Tahir Shah 2008 37: 341Journal of Industrial Textiles DOI: 10.1177/1528083707081594 The online version of this article can be found at: https://www.doczj.com/doc/b72530452.html,/content/37/4/341 Published by: https://www.doczj.com/doc/b72530452.html, can be found at:Journal of Industrial TextilesAdditional services and information for https://www.doczj.com/doc/b72530452.html,/cgi/alertsEmail Alerts: https://www.doczj.com/doc/b72530452.html,/subscriptionsSubscriptions: https://www.doczj.com/doc/b72530452.html,/journalsReprints.navReprints: https://www.doczj.com/doc/b72530452.html,/journalsPermissions.navPermissions: https://www.doczj.com/doc/b72530452.html,/content/37/4/341.refs.htmlCitations: - Mar 28, 2008Version of Record >>
Strategic transformations in Danish and Swedish big business in an era of globalisation, 1973-2008 The Danish and Swedish context In the difficult inter-war period, a state-supported, protected home market orientation had helped stabilise both Denmark’s and Sweden’s economies, but after WorldWar II priorities changed. Gradually and in accordance with the international economic development, restrictions on foreign trade were removed, and Danish and Swedish industry was exposed to international competition. As a consequence, several home market oriented industries –such as the textile and the shoe industry –were more or less outperformed, while in Sweden the engineering industry soon became the dominant leader of Swedish industry, with companies such as V olvo, Ericsson, Electrolux, ASEA and SKF. In the Danish case, the SMEs continued to be dominant but in combination with expanding export oriented industrial manufacturers such as Lego, Danfoss, Carlsberg and the shipping conglomerates ok and A.P. moller-Marsk. In Sweden and Denmark stable economic growth continued into the 1970s, but due to the problems during the oil crises, the economies came into fundamental structural troubles for the first time since World War II. In the beginning this was counteracted by traditional Keynesian policy measures. However, because of large budget deficits, inflation and increasing wages, both the Danish economy from 1974 and the Swedish economy from 1976 encountered severe problems. Towards the late 1970s Denmark’s and Sweden’s economic policies were thus increasingly questioned. It was clear that Keynesian policy could not solve all economic problems. Expansive fiscal policies in terms of continued deficits on the state budget could not compensate for the loss of both national and international markets and step by step the Keynesian economic policy was abandoned. The increased budget deficit also made it difficult for the state to support employment and regional development. These kinds of heavy governmental activities were also hardly acceptable under the more market oriented policy that developed first in Great Britain and the USA, but in the 1980s also in Denmark and Sweden (Iversen & Andersen, 2008, pp. 313–315; Sjo¨ gren, 2008, pp. 46–54). These changes in political priorities were especially noticeable in the financial market. After being the most state regulated and coordinated sector of the economy since the 1950s, then between 1980 and 1985 the Danish and Swedish financial markets underwent an extensive deregulation resulting in increased competition. Lending from banks and other credit institutes was no longer regulated, and neither were interest rates. The bond market was also opened as the issuance of new bond loans was deregulated in Sweden in 1983. When the control of foreign capital flows was liberalised in the late 1980s the last extraordinary restriction was now gone. Together with the establishment of the new money market with options and derivates, this opened up to a much larger credit market and the possibility for companies to finance investments and increase business domestically as well as abroad (Larsson, 1998, pp. 205–207). Another important part of the regulatory changes in the early 1980s were new rules for the Copenhagen and Stockholm stock exchanges. Introduction on the stock exchange was made much
外文文献： Risk Analysis of the International Construction Project By: Paul Stanford Kupakuwana Cost Engineering Vol. 51/No. 9 September 2009 ABSTRACT This analysis used a case study methodology to analyse the issues surrounding the partial collapse of the roof of a building housing the headquarters of the Standards Association of Zimbabwe (SAZ). In particular, it examined the prior roles played by the team of construction professionals. The analysis revealed that the SAZ’s traditional construction project was generally characterized by high risk. There was a clear indication of the failure of a contractor and architects in preventing and/or mitigating potential construction problems as alleged by the plaintiff. It was reasonable to conclude that between them the defects should have been detected earlier and rectified in good time before the partial roof failure. It appeared justified for the plaintiff to have brought a negligence claim against both the contractor and the architects. The risk analysis facilitated, through its multi-dimensional approach to a critical examination of a construction problem, the identification of an effective risk management strategy for future construction projects. It further served to emphasize the point that clients are becoming more demanding, more discerning, and less willing to accept risk without recompense. Clients do not want surprise, and are more likely to engage in litigation when things go wrong. KEY WORDS:Arbitration, claims, construction, contracts, litigation, project and risk The structural design of the reinforced concrete elements was done by consulting engineers Knight Piesold (KP). Quantity surveying services were provided by Hawkins, Leshnick & Bath (HLB). The contract was awarded to Central African Building Corporation (CABCO) who was also responsible for the provision of a specialist roof structure using patented “gang nail” roof
毕业论文外文文献翻译 毕业设计（论文）题目关于企业内部环境绩效审计的研究翻译题目最高审计机关的环境审计活动 学院会计学院 专业会计学 姓名张军芳 班级09020615 学号09027927 指导教师何瑞雄
最高审计机关的环境审计活动 1最高审计机关越来越多的活跃在环境审计领域。特别是1993-1996年期间，工作组已检测到环境审计活动坚定的数量增长。首先，越来越多的最高审计机关已经活跃在这个领域。其次是积极的最高审计机关，甚至变得更加活跃：他们分配较大部分的审计资源给这类工作，同时出版更多环保审计报告。表1显示了平均数字。然而，这里是机构间差异较大。例如，环境报告的数量变化，每个审计机关从1到36份报告不等。 1996-1999年期间，结果是不那么容易诠释。第一，活跃在环境审计领域的最高审计机关数量并没有太大变化。“活性基团”的组成没有保持相同的：一些最高审计机关进入，而其他最高审计机关离开了团队。环境审计花费的时间量略有增加。二，但是，审计报告数量略有下降，1996年和1999年之间。这些数字可能反映了从量到质的转变。这个信号解释了在过去三年从规律性审计到绩效审计的转变（1994-1996年，20％的规律性审计和44％绩效审计;1997-1999：16％规律性审计和绩效审计54％）。在一般情况下，绩效审计需要更多的资源。我们必须认识到审计的范围可能急剧变化。在将来，再将来开发一些其他方式去测算人们工作量而不是计算通过花费的时间和发表的报告会是很有趣的。 在2000年，有62个响应了最高审计机关并向工作组提供了更详细的关于他们自1997年以来公布的工作信息。在1997-1999年，这62个最高审计机关公布的560个环境审计报告。当然，这些报告反映了一个庞大的身躯，可用于其他机构的经验。环境审计报告的参考书目可在网站上的最高审计机关国际组织的工作组看到。这里这个信息是用来给最高审计机关的审计工作的内容更多一些洞察。 自1997年以来，少数环境审计是规律性审计（560篇报告中有87篇，占16％）。大多数审计绩效审计（560篇报告中有304篇，占54％），或组合的规律性和绩效审计（560篇报告中有169篇，占30％）。如前文所述，绩效审计是一个广泛的概念。在实践中，绩效审计往往集中于环保计划的实施（560篇报告中有264篇，占47％），符合国家环保法律，法规的，由政府部门，部委和/或其他机构的任务给访问（560篇报告中有212篇，占38％）。此外，审计经常被列入政府的环境管理系统（560篇报告中有156篇，占28％）。下面的元素得到了关注审计报告：影响或影响现有的国家环境计划非环保项目对环境的影响;环境政策;由政府遵守国际义务和承诺的10％至20％。许多绩效审计包括以上提到的要素之一。 1本文译自：S. Van Leeuwen.(2004).’’Developments in Environmental Auditing by Supreme Audit Institutions’’ Environmental Management Vol. 33, No. 2, pp. 163–1721
外文翻译 原文 Foreign T rade o f China Material Source:W anfang Database Author:Hitomi Iizaka 1.Introduction On December11,2001,China officially joined the World T rade Organization(WTO)and be c a me its143rd member.China’s presence in the worl d economy will continue to grow and deepen.The foreign trade sector plays an important andmultifaceted role in China’s economic development.At the same time, China’s expanded role in the world economy is beneficial t o all its trading partners. Regions that trade with China benefit from cheaper and mor e varieties of imported consumer goods,raw materials and intermediate products.China is also a large and growing export market.While the entry of any major trading nation in the global trading system can create a process of adjustment,the o u t c o me is fundamentally a win-win situation.In this p aper we would like t o provide a survey of the various institutions,laws and characteristics of China’s trade.Among some of the findings, we can highlight thefollowing: ?In2001,total trade to gross domestic pr oduct(GDP)ratio in China is44% ?In2001,47%of Chinese trade is processed trade1 ?In2001,51%of Chinese trade is conduct ed by foreign firms in China2 ?In2001,36%of Chinese exports originate from Gu an gdon g province ?In2001,39%of China’s exports go through Hong Kong to be re-exported elsewhere 2.Evolution of China’s Trade Regime Equally remarkable are the changes in the commodity composition of China’s exports and imports.Table2a shows China’s annu al export volumes of primary goods and manufactured goods over time.In1980,primary goods accounted for 50.3%of China’s exports and manufactured goods accounted for49.7%.Although the share of primary good declines slightly during the first half of1980’s,it remains at50.6%in1985.Since then,exports of manufactured goods have grown at a much