| dc.description.abstract | In recent years a number of geodesists have
proposed the application of three-dimensional geodesy
in the setting up of terrestrial geodetic control
networks. The relevant formulations have been presented
and actual networks computed to demonstrate the validity
of the method. However, one aspect that appears not to
have been adequately tackled is the optimal design for
such networks. Reported herein is an investigation into
the optimal design problem for three-dimensional terrestrial
geodetic networks with reference to a specific network.
A real network forming a part of the geodetic
network of Kenya was adopted for the study. The
network is basically a triangulation chain and consists
of 36 stations with observational lines ranging from
21 km to 95 km.
The effect of type and number of observations
on the network were systematically investigated with
the aim of eventually arriving at an optimal model
of the network. The types of observations considered
were vertical angles, horizontal-directions, spatial
distances, astronomic ~azimuths, astronomic latitudes, and
astronomic longitudes. The study was conducted entirely
by computer simulation.
From an analysis involving 65 models of the network,
an optimal model is offered. The results indicate,
among other factors, that with all the possible horizontal
directions and vertical angles observed in the network,
astronomic positions need to be determined at about one-half
of the stations in the network; astronomic azimuths at
about one-quarter of the stations; and between one-tenth and
one-eighth of the possible spatial distances. | en |
