The following information is recorded for observations (whether boundary
or traverse) that have been captured or converted:
| Observation Value |
The actual value (eg. "20.12"). Bearings,
distances, and arcs are each recorded as separate (independent) observations.
The bearing directions have been captured as they appear on the survey
plan, while distances in links have been converted to metres. In the
case of arcs, some information may have been calculated. |
| Observation Type |
The system records whether the value is a bearing, distance,
or arc observation. |
| Observation Class |
Observations may be Measured, Calculated, or Adopted,
as indicated on the survey plan. This affects the accuracy value that
is assigned to each observation. |
| Date |
This is usually the same as the date of the survey,
and affects the accuracy value that is assigned to each observation
(older surveys are generally less accurate). |
| Coordinate System |
This is the same as the coordinate system recorded for
the survey. It is used to enable the application of bearing swings
during the adjustment process. Landonline does not relate
this to any coordinates. |
| Accuracy |
Each observation must be assigned an accuracy value in Landonline.
This is an essential input into the least squares adjustment process.
Landonline and Survey Conversion use a number of parameters
and values to calculate the value. These may include the type, date,
class, and length of the observation, and the type of equipment.
Where observations have been shown to be problematic (mainly historical
observations on Survey Conversion rather than on new surveys), they
may have been down-weighted during the adjustment process.
|
| Boundary Dimension |
Landonline records explicitly that an
observation is a boundary dimension for a specific parcel. This is
recorded through a simple link between the observation and the parcel
to which it relates. This link is used to display the boundary dimensions
for a parcel in the spatial window. A small number of parcel boundaries
(eg balance distances on part parcels) are not linked to the parcel,
as the dimension has not been explicitly defined as such on a survey
plan for that (balance) parcel. |
| Survey Reference |
Landonline records a link between the
observation and its survey. |