Example: Vancouver_2002

• The ORM object

  • The Earth (This case is called an ERM-Earth Reference Model)

• The ORM model

  • A sphere RD of radius 6 377 500m.

• The ORM object binding

  • 1. Pick a spot on the ground in Vancouver (The base of the
    Gastown Steam Clock).
  • 2. Measure the direction of “up” at the spot (The Vancouver
    Normal).
  • 3. Measure the elevation of the star Polaris with respect to the
    Vancouver Normal - This determines the latitude of the
    Vancouver spot.
  • 4. The model binding: There is one and only one sphere in
    space satisfying these conditions:
    • Radius = 6377500m,
    • Axis intercepts Polaris,
    • Vancouver spot is on the surface at latitude = latitude of the Vancouver spot, and
    • The surface normal at the Vancouver spot coincides with the Vancouver Normal.

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