2003 Sep 05

Kentucky GIS Forum, Sep 16, 2003

GIS Quality Enhancement by Professional Surveyors

The Survey Analyst and Spatial Management for the Enterprise GIS

Building on the GeoDataBase, Survey Analyst provides a new layer type in the GIS, adding to Vector, Raster, Annotation, and Graphic. We consider the Measurement Layer, for the Surveyor and for the GIS. It is the only layer provided with an explicit lock. Previously, the work of the Surveyor has been disconnected from the GIS, handed over like orphaned eggs in the form of points, from which features may be fostered.

Today, the gathering of data from field observations, with a growing variety of tools and methods, is managed by the Surveyor with varying software that ultimately transforms observational measurements into more or less attributed doubles or triples: X,Y or X,Y,Z. From each measuring device, flows information, supplemented by the Surveyor, typically passing through a variety of data formats, and includes substantial information, characterizing the context of the point, the attributes of measurement, and the attributes of the computed result, generally in terms of Quality, i.e. accuracy, fidelity. Today, most of that information is outside the eggshell and lost to the GIS.

That information (type of metadata) is the basis for Quality -- the payoff to the GIS for these survey layers. Until now, the quality of a GIS can only roughly be stated, and typically cannot be verified. Successful implementation of the Survey Analyst into the enterprise GIS will provide for more complete characterization and validation of accuracy on the feature layer in the GIS generally named Control, the foundation of the GIS.

Moreover, the previously irregular, multi-step workflow from field measurement to Control point is now collapsed into a 2-step flow from the measurement device, to the collector, to ArcGIS software. All related information has a home in the GeoDataBase, and is available to built-in computations reducing the data to coordinate results while retaining and providing the basis for Quality.

We may consider a strategy for implementing methods of communication between the surveyor and the GIS, for example as maintained by the PVA, providing the citizens of the county optimum benefit of technology now available.

John R. Schmidt, Master of Science

President, NCAD Corporation

Authorized Softdesk Dealer 1988 - 1996

Instructor, ESRI Authorized Training Program

ESRI Business Partner since 1989

463 Erlanger Rd

Erlanger, KY 41018-1427

859 727-9999

fax 727-6789

john@ncad.net

 

John Schmidt is a 1968 graduate of Beechwood High School in Northern Kentucky, and Williams College, Massachusetts in 1972 majoring in the study of the phenomenology of religion. After additional premedical coursework, he attended U. Cincinnati College of Medicine from 1973-76 scoring 60 points above class average on National Medical Board of Examinations Part 1. He was oddly dismissed "for poor scholarship" near the end of Year 3. During 1977 - 1981 he operated as a general contractor, learning from tradesmen, inspectors, and at the library.

In 1985 he completed the 4-year, full-time program earning the Master of Science from the Department of Electrical and Computer Engineering at the U. Cincinnati College of Engineering. During a 17-month period with ComputerLand he became focused on AutoCAD as a platform supporting applications in Survey and Civil Engineering, committing to (DCA Engineering Software, which became Softdesk, acquired by Autodesk in 1996, continuing now as Land Development Desktop) as he started NCAD in 1988.

In 1989, he attended the first ESRI Business Partner meeting and trained on PC Arc/Info; in 1991 on ArcCAD; and 1992 on ArcView. He continues the strategy of complete familiarity with all ESRI technology, most recently completing training on the GeoDataBase. He is Authorized Instructor for ArcView, ArcGIS I, and ArcGIS II.

In 1995, he began research on the Global Positioning System culminating in the Microsoft Excel - based Normalized Summary of the 1995 UNAVCO GPS Receiver/Antenna Test Report, distributed at the ACSM Conference in 1996.

This represents the first clarification of differences between high-end GPS receivers. Based on that result he configured a GPS Reference Station at a summit in Erlanger, KY, the continuing home of NCAD Corporation. CORS Erla, the first privately operated Continuously Operating Reference Station filled a gap, in 1996, within the triangle of: St. Louis, Detroit, and Gaithersburg, MD. After 16 months of operation the NGS director of CORS documented that "The vertical repeatability of this CORS site (sigma = 0.55cm) is more than two times smaller than that found for essentially all of the other CORS sites."

NCAD provides complete computer solutions based on Intel, Microsoft, and Cisco technology, with particular focus on application support for CAD and GIS. Other publications are cataloged at http://NCAD.Net, including: