18-Geom-A7 Geospatial Information Systems · May 2014
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
National Exams — May 2014 — 04-Geom-A7 Geospatial Information Systems. Closed-book; no calculator permitted. Format: twenty-three short-answer questions of equal value (5 marks each); a candidate answers any twenty, but all twenty-three are solved in full below. Datum and coordinate conventions follow the Canadian spatial reference framework — NAD83(CSRS) horizontally and CGVD2013 vertically.
Reference texts: P. A. Longley, M. F. Goodchild, D. J. Maguire & D. W. Rhind, Geographic Information Systems and Science (4th ed., Wiley, 2015); P. Bolstad, GIS Fundamentals: A First Text on Geographic Information Systems (6th ed., XanEdu, 2019); P. A. Burrough, R. A. McDonnell & C. D. Lloyd, Principles of Geographical Information Systems (3rd ed., Oxford, 2015); M. Worboys & M. Duckham, GIS: A Computing Perspective (2nd ed., CRC, 2004); ISO 19115 Geographic information — Metadata.
Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.
All three handle graphic spatial information, but they differ in purpose, data structure and analytical capability. Automated (computer-assisted) cartography is oriented to map production and display: it manages symbology, generalization, labelling and plotting to make cartographically correct output, but it stores little attribute information and offers essentially no spatial query or analysis — its goal is a good-looking map. CAD (computer-aided design/drafting) is oriented to precise geometric drafting and design: it excels at accurate coordinate geometry, layers and drawing entities, and is ideal for engineering plans, but traditional CAD lacks a georeferenced coordinate system, has weak or no topology, and links only limited attributes to entities, so it cannot readily answer spatial questions across features. GIS integrates georeferenced spatial data and a linked attribute database, maintains topology, and — the decisive difference — supports spatial query and analysis (overlay, buffering, network and proximity analysis, interpolation) to support decision-making, in addition to producing maps. In short: automated cartography makes maps, CAD draws precise geometry, and GIS additionally models spatial relationships and analyses them; only GIS ties geometry, topology and attributes together for analysis.
