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The primary goal of the current gravity gradiometer research at Stanford has been to establish the feasibility of using a gravity gradiometer with 1 E accuracy, as the primary sensor in various applications. The two applications considered here in detail are geodesy missions and inertial navigation systems. Preliminary sections on gravity models and gravity gradiometer bias estimation are also included. (Author).

The application of the linearized theorized of Robotnov and Shesterikov and of Onat and Wang to creep buckling is examined and an investigation of the associated disturbance-response behavior is made. It is shown that a precise and consistent criterion for stability that has both theoretical and experimental support is possible within the scope of linearized theory. The linearization procedure of Onat and wang is extended to multiaxial stress states and the problem of a compressively loaded rectangular plate subject to creep is analyzed. (Author).

An analysis of creep rupture of ductile materials subjected to strain hardening creep is presented. The analysis is similar to an earlier one by Hoff, but is based on a different generalization of the primary creep rate relation. Both approaches are then extended to time hardening creep. Simple approximate formulae for critical times are presented and the results of both approaches for the two types of creep are compared. Correlation with experimental data for some aluminum-copper, aluminum-magnesium and aluminum-zinc alloys shows fairly good agreement of rupture times for these very ductile materials. However, attempted correlation with data for other materials which do not exhibit such prominent ductility indicates that the basic assumption of the analysis, that creep rupture is caused primarily by a process of reduction of area, holds only for very ductile materials.