Appendix 1 - Data Collection and Analysis Methodology

Appendix 1 - Data Collection and Analysis Methodology. Importing the AutoCAD .dwg files, supplied by Facilities Management SFU, and initially resulted in the absence of text and the presence of line coverages. Polygon and annotation coverages were available after opening both the folders and the .dwg files.

       Each layer within the .dwg file was extracted and converted to an ArcView shape file. A poor alignment of the shapefiles and source digital orthophotos was noted. World files for the colour orthophotos were, apparently, not available. ArcView Program Extension files were downloaded to remedy the misalignment but did this poorly. World files for the colour orthophotos were, eventually, located. Facilities Management AutoCAD .dwg files did, then, align correctly.

       New black and white orthophotos and AutoCAD .dwg files were obtained from Facilities Management, SFU.

The new .dwg files, with the supplied world files, lined up perfectly with the supplied orthophotos. Unfortunately, the new .dwg files did not line up with the shape files that were made from the Facilities Management, original .dwg, files - they were offset by over two kilometers. This indicated that one of the data sets was incorrect. A projection error was not anticipated as the location of a graticule theme in each of the data sets exactly matched the UTM coordinates.

       The two datasets represented differing projections: Facilities Management/colour orthophotos in UTM83 Zone 10 and street network file (.snf) from the Federal Canadian 1996 Census in NAD27. The census street network file was subsequently replaced with a more sophisticated road network coverage from Computer Innovations.

       Decimal degree format was the only reprojection option within ArcView. The Projector ArcView extension was installed from C:\temp. All shape files were then converted to decimal degrees. Essential ArcView Avenue scripts could then be employed.

       Additional coverages were heads-up digitized from source documents. Rotational and x,y translation errors were encountered during orientation of the coverages with the digital orthophotos. The program Freehand was used to scale and rotate the coverages and orthophotos. The digitized coverages were cut and pasted into Corel Draw and then exported as .dxf AutoCAD format files, which were importable into ArcView. World files to align the coverages with the digital orthophotos were then employed. The polyline coverages required further conversion to polygon coverages. The ArcView Avenue script View_LineThemes2PolygonTheme.ave was downloaded from the ESRI web site. Polygon coverages were created after running this script.

       Road network analysis was facilitated by Edit Tools 2.0 ArcView extension. This sample extension is only useful for shapefiles containing less than one hundred features. Pseudo-nodes and dangling nodes are identified and polylines are split at intersections.

       Transparent fills, although displayed by ArcView, could not be printed until an additional ESRI technical hint was located and the methods applied to numerous layouts. Vector fills were loaded into the Symbol Palette that changed the solid fill to a vector dot coverage.

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