| Popis: |
GPS is actually becoming a standard tool for determining discrete point-configurations within geodetic networks, and the combination of GPS with usual terrestrial measurements is presently coming to be a typical kind of geodetic network. For such GPS—terrestrial as well as for free engineering networks which are to be linked to some fix points e.g. of a superior network, there arises the question of selecting the best point—positions for their fixing with respect to a given discrete number of supporting-points in the sense of an optimality criterion. In this context JAGER and DRIXLER, 1989 show that the optimum positions for fix—points are not receivable and identical, respectively to those points which get the number of maximum weights in the weight—hierarchy of an ‘all—point Third Order Design aproach’. The following recently developped optimization method (JAGER and DRIXLER, 1989) for optimum supporting point—positions is founded in the concept of spectral network—analysis (JAGER, 1988; WIESER, 1988) and spectral optimization of geodetic networks (JAGER, 1988), both referring to spectral criterions and target functions respectively. The decisive spectral target function of a maximum contraction of the eigenvalue—spectrum of the covariance-matrix of network—coordinates provides for the best possible homogenization of the error situation and the best possible stability or strength respectively of the regarding network. The latter criterion is similar to an optimum stiffness of the network in the sense of valuable mechanical analogies (JAGER, 1988). |
