Journal of Surveying Engineering

Most activities supported by geodesy are under state jurisdiction. But the main governmental organization that is purely geodetic is federal: the National Geodetic Survey (NGS). NGS (before 1970, as the U.S. Coast & Geodetic Survey) established the fundamental network for the entire country. In the last two decades the field operations of NGS have decreased greatly, as its role has shifted to research and development, prescribing standards and specifications, technology transfer, computations and adjustments, and data base management. These trends are consistent with the policy that the federal government should concentrate on activities that are unique or national. The question is not so much government versus private sector, but rather how much geodetic activity should be transferred from the federal government to the states.

An individual's view on the public‐private division of responsibility depends to a large extent on how he or she earns a living. In other words, where you stand depends on where you sit. Having served in government for twenty years, I can appreciate the public sector's philosophy; however, time has shown that unbridled growth in the public sector cannot be tolerated. In this paper I present a logical argument that clearly defines the public‐private sector involvement in the geodetic surveying area.

The respective roles of government and the private sector in geodetic surveying are relative and whatever they are now, they are about to change. To a major degree existing roles have been established by: (1) National interest and need; (2) economics; and (3) technology. The latter two are intertwined. The extent of the existing National Geodetic Reference System (NGRS), for example, was based partly on the need to provide sufficient density to permit local surveys (private or government) access to the datum within certain economic bounds. These economic bounds are driven, almost exclusively, by the methodologies used. GPS has the potential for changing these economic boundaries and, therefore, revising the nature of geodetic reference systems. A backbone national reference system at 500 km spacing with secondary stations spaced between 50 km and 200 km should suffice in a full GPS environment.

The geodetic system composed of geodetic service providers, geodetic service users, and the American public, is becoming more active and complex as a result of recent technological development in Global Positioning System (GPS) equipment and technique. In order to further land information goals and meet immediate resource management needs, the following are seen as the primary goals to be achieved by the geodetic survey community: (1) Geodetic standards for survey, monumentation, and record‐keeping must be uniform, attainable, and realistic for all users nationwide; (2) the system should provide for the easy submittal of geodetic information at a central record center, maintenance of the information file in an up‐to‐date condition, and easy retrieval of information by all users; (3) the mainframe of high order control should be established, maintained, and the existing network upgraded to accommodate the perpetually improving land management capabilities; and (4) project level geodetic survey services need to be readily available at reasonable costs to make the network a usable tool in improving land management capabilities.

A detailed proposal describing the roles of the federal, state, and local governments, and the private sector, is presented. Functions are classified according to traditional methods, taking into account new technologies, and recognizing that organizations other than the federal government can perform these traditionally governmental functions. Functions in geodetic surveying are classified according to mandates or legislation, although no absolute mandates have been enacted for most of the functions. Techniques are not discussed explicitly since no organization has an exclusive right to perform a particular method. Instead, performance of surveys, management of geodetic data, and computation and adjustment of geodetic observations are covered. The concept of a multipurpose cadastre (MPC) has become a reality in a few areas of the country. The MPC is clearly located within the local government's area of responsibility with the amount of state and federal activity remaining to be determined. Finally, certain functions are identified at the state and local level, including the requirement that surveys be tied to the National Geodetic Reference System.

Counties should be involved with geodetic control surveys and should maintain county‐wide information services. Such involvement should include: (1) Maintaining files of horizontal and vertical control information; (2) supervising, coordinating, and/or documenting local densification efforts; (3) encouraging or requiring local projects to be referenced to the state plane coordinate system; (4) encouraging or requiring local projects to be referenced to national vertical control data; (5) encouraging or requiring major local networks to contribute to the national geodetic networks; and (6) maintaining geodetic surveying monuments and/or reporting monument conditions to the appropriate agency.

The role of federal, state, and local governments in geodetic surveying was studied by the ASCE Geodetic Surveying Committee in the late 1970s and early 1980s. In 1984, the private sector role was also included in the study and a group of invited speakers from federal, state, and local governments as well as the private sector made presentations on it at the 1986 ASCE Spring Convention in Seattle, Washington. Following the presentations, the authors convened as a panel and discussed questions from the audience and other panelists. This paper is a summary of that discussion as recorded by the session moderator.

This paper introduces the surveying engineer to expert systems. Expert systems are computer systems that advise on or help solve real‐world problems requiring an expert's interpretation. They approach real‐world problems using a computer model of expert human reasoning. Facts and rules are part of what is known as the knowledge base. These can be represented using first‐order predicate logic, semantic nets, and frames. Exploitation of the knowledge base is controlled by the strategies of state space search and the use of pattern matching programs. Construction of expert systems is an expensive affair where knowledge acquisition plays a critical role. One of the major limitations in building expert systems is our current lack of understanding of expert human decision‐making. However, such systems provide a powerful vehicle for furthering our understanding of those processes and applying that understanding to the solving of engineering problems.

Expert system efforts of particular importance to the development of Geographic Information Systems are evaluated. Three general problem domains are identified as automated map design and generalization, terrain/feature extraction, and geographic database management/user interface. Within each problem domain we critically assess each of the reported systems. There is a paucity of efforts directed at developing expert systems for land records systems. We review prospective areas for the application of expert systems to problems of land records systems. It is concluded that expert systems for geographic information system applications can be built. However, it is not yet advisable to begin large‐scale projects.