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Many surveyors use the network of global positioning system (GPS) Continuously Operating Reference Stations (CORS) as accurate 'free' control monuments in their projects. The National Geodetic Survey (NGS) publishes and maintains coordinates for these stations in terms of X, Y, Z, and latitude, longitude, and ellipsoidal heights. This information is very useful for horizontal positioning but not for vertical positioning. Establishing the orthometric heights of a CORS station will enhance its usefulness to surveyors and geodesists. In this paper, a method for determining orthometric heights for CORS is described and evaluated. The implementation of the proposed procedure at the NJI2 CORS station produced an orthometric height with a standard deviation of [+ or -] 1 mm. DOI: 10.1061/(ASCE)0733-9453(2003)129:3(110) CE Database subject headings: Surveys; Height; Methodology.

In areas that are subject to tidal waters, projects such as bridge construction and property boundary location require the determination of the water level or water datum. Of the different water data that can be established, the mean high water (MHW) is of prime importance. To establish the MHW line at a project site, it is necessary to either make long-term (19 years) continuous tide observations or to perform simultaneous short-term tide observations at points in the vicinity of the project and at a tidal control station. Of the three short-term observation and computation methods for determining the MHW, the amplitude ratio method is applicable in most general circumstances. The current computation procedure of the amplitude ratio method utilizes graphic means to determine the tide amplitude. A new analytical solution for this method was developed using least squares principles. The advantages of the proposed solution are simplicity of computation, suitability for automatic data processing, and usability even with incomplete observation data sets. CE Database keywords: Tidal water; Water levels; Analytical techniques; Amplitude.

Coordinate transformation is the process of determining and applying the relationship between two sets of coordinates. It answers the following question: 'I know the coordinates of a point on one data source, what are the coordinate values for this point on another data source?' In most cases, points do not have homogeneous accuracies; thus, they must be weighted according to their relative values. An important objective of this procedure is to keep it as simple as possible so that it can be easily adopted by professional land surveyors or geographic information system (GIS) technical staff. Another important objective of the coordinate transformation process is to make it statistically sound. A weighted least squares is probably one of the better solutions for the transformation problem. Weighted least squares-based coordinate transformation has many applications in surveying practice. One application is to compute NAD83 coordinate values for points with known coordinate values in another plane coordinate system such as NAD27, UTM or NAD83 (19xx), where 'xx' is the year in which the adjustment was computed. Another application is to combine maps from different sources or to register a map to an orthophoto when building a GIS. A third example of an application is to sort out evidence in boundary surveys.

The trip making process using transit versus private automobile differs in the use of time schedules, walking paths, transfer stops, plus issues such as fare and safety. Due to these factors, many of the standard shortest path algorithms do not apply. The purpose of this study is to develop an algorithm and strategy for transit providers to find best alternatives for the user, and to demonstrate how a geographic information system can be used in the development of transit advanced traveler information system (TATIS) to meet these needs. This paper presents a short introduction to TATIS systems, some commonly used algorithms in determining the shortest and multiple paths, and a new strategy that was developed in this study which differs from standard network algorithms. The major features of this proposed algorithm are: (1) Capability of handling multiple modes of transit; (2) providing paths that include walking distances from and to the transit path as well as between transfer points; and (3) provision of multiple optimal paths to allow the user flexibility in choosing a path.

The article discusses the relationship between geographic information systems (GIS) and surveying. An overview of the Association of American Geographers (AAG)/ University Consortium for Geographic Information Science (UCGIS) GIS body of knowledge is presented. It also provides a detailed description of the GIS body of knowledge specifically formulated for surveying.

A profession is founded on knowledge, skills, and education. The knowledge, skills, and education required to practice within a profession should be defined in a body of knowledge of that profession. This is the first edition or the first comprehensive attempt to define the surveying body of knowledge. This work was initiated about three years ago, by the American Congress on Surveying and Mapping and the North American Surveying Educators organization. A special body of knowledge committee was established to carry out this task. The committee decided to develop a six part surveying body of knowledge. The first is a general body of knowledge, termed as the macro level body of knowledge which is presented in this paper. The other five specific detailed subset (micro level) bodies of knowledge in the areas of positioning, imagery, geographic information systems, law, and land development. The paper introduces the philosophical and conceptual considerations on which the body of knowledge was founded and provides details on the macro level body of knowledge. [ABSTRACT FROM AUTHOR]

The evolution of new positioning and information technologies fundamentally challenges the way surveying is practiced. These innovative developments require new skills and knowledge that a professional surveyor must possess in order to become productive, effective, and successful. Therefore, it is necessary to revisit the current educational and professional paradigms necessary to prepare competent future professional surveyors. Some of the important professional and educational issues to be addressed are: What should be taught and learned? How should it be taught and learned? and Who should teach it and learn it? The objective of this paper is to address educational and professional challenges of the surveying profession and suggest an outline for the body of knowledge needed to prepare competent professional surveyors for the 21st Century. [ABSTRACT FROM AUTHOR]

The U.S. Bureau of Labor Statistics (USDL 2006) predicts job openings for surveyors at nearly 3000 a year over the next ten years. An active vigorous effort aimed at successfully recruiting matriculated students to pursue a course of study in surveying may ensure adequate supply of highly skilled and qualified surveyors. Despite recent commendable efforts by the National Society of Professional Surveyors (NSPS) to give public exposure to the surveying profession, the general public remains largely uninformed about the work and skills of professional surveyors and their vital role in protecting the public good, which, in turn, constricts student recruitment. We report the results of several pilot studies conducted in the State of New Jersey of student enrolment in the Surveying Engineering Technology (SET) Program at the New Jersey Institute of Technology (NJIT). In addition, we report a sample response of national perceptions on surveying careers from interviews conducted in northern New Jersey. This study examines how and why students chose surveying as a career path and then identify key elements of a recruitment model within the framework of vocational planning theory. A skeletal recruiting model is proposed, which takes into account factors shaping recruitment messages targeted at specific audiences, support for behavioral control, reinforcement of positive attitude, and stimuli in the student milieu. We recommend that the recruitment message include features of role models and effective communication style, and its language should be devoid of gender mainstreaming. High-tech surveying imagery should be used to further erode antiquated visions of mediocre surveying education and careers. [ABSTRACT FROM AUTHOR]

The Geographic and Land Information Society (GLIS) is the youngest and the smallest member organization of the American Congress on Surveying and Mapping (ACSM). The main goal of GLIS is to bridge the gap between traditional surveying and mapping professionals and the GIS community. In spite of its modest size, GLIS has had a considerable impact on both professional communities. The society was instrumental in bringing about the realization of the importance of surveying within the GIS community. The GIS community is becoming more aware of the importance of surveying to GIS, and of the importance of the surveyor's participation in GIS activities. One example of this recognition was the inclusion of surveying activities (spatial data compilation) as GIS professional experience in the Urban and Regional Information Systems Association's GIS certification criteria. The Geographic and Land Information Society is also making headway in making the surveying community more aware of the need to become involved in GIS, by promoting GIS activities in State Surveying Societies and by providing educational opportunities for surveyors at ACSM and other surveyors' conferences. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editor discusses various reports within the issue on topics including the educational requirements needed to acquire surveying knowledge, the level of competency required in the various surveying specialties, and details of GIS and land development bodies of knowledge regarding surveying.

A crucial component in developing an effective GIS based on digital parcel base maps is the acquisition of accurate digital land base data. Accurate land base data make spatial analysis less troublesome andenables better decision making. However, acquisition of accurate spatial data from traditional data compilation techniques could come with a hefty price tag. A popular solution for the accuracy versus cost dilemma is the use of USGS Digital Orthophoto Quadrangles (DOQ). DOQsprovide very inexpensive continuous land coverage that could be converted with relatively modest means and expense into a digital parcel map. Given that DOQs are becoming a common solution for establishing digital parcel coverages, it is prudent to evaluate their accuracy. DOQs are considered to comply with the National Mapping Accuracy Standards (NMAS), but that statement does not render a constructive measure for the accuracy of the data because of the way (or lack of) a dataset is certified as being in compliance with the NMAS. A better approach for evaluating the accuracy of DOQs is to follow the National Standard for Spatial Data Accuracy (NSSDA) guidelines. In this paper a DOQ was evaluated with the NSSDA standards in order to establish the positional accuracy of the data. The accuracy was found to be within 25 feet (7.6 m) at the 95 percent confidence level. The DOQ was also evaluated for its geometric, radiometric, and mosaicking accuracies. This aspect of the DOQ was found to be satisfactory. Finally, the appropriateness of DOQs in the context of a parcel-based GIS was addressed. [ABSTRACT FROM AUTHOR]