Die Schwerewirkungen eines elliptischen Zylindersegmentes

Summary A method has been derived for computing the gravity effect of a segment of an infinite homogeneous elliptical cylinder. The initial data was represented by formulae expressing the components of the field of gravity of a homogeneous two-dimensional body by means of line integrals. The method is based on the integration of theln R function over the boundary of the cross-section of the attracting body, R being the distance from a fixed point in which the gravity effect is determined. The problem was solved in confocal co-ordinates.     

Schlierenoptische Untersuchungen der kinematischen und dynamischen Parameter von Oberflächenwellen

Summary An attempt was made to apply the Schlieren method for the investigation of kinematic and dynamic parameters of surface waves. The wave field generated by an exploding wire was studied in two-dimesional plexiglas models of a half space. Travel-time curves of the observed wave groups are given. Densitograms of surface waves obtained by microphotometric profiling parallel or perpendicular to the direction of the wave propagation enable to estimate the horizontal or vertical components of compressional stresses forming these waves.     

Beglaubigung der Dimension astronomisch-geodätischer Netze der ČSSR und Udssr aus Messungen mit dem Geodimeter NASM-2A

Summary A method is described, based on the calculus of observations, of testing the transferring of a length dimension by means of invar wires from the national standard via the geodetic comparative base to field geodetic bases, assuming that some of them have been measured electrooptically. The method is demonstrated on Czechoslovak and Soviet bases. In both cases the transfer of the length was proved to be successful. It was also found that, as regards the accuracy, it is immaterial whether the given base is measured electro-optically as a whole or in parts.     

Statistical characteristics of geophysical fields in Hilbert's space

Summary A review of the terms of functional analysis, which can be exploited for statistical treatment of geophysical fields, is given. The procedure for determining the statistical characteristics of the fields, defined by a single realization, which does not require the limiting assumption of homogeneity to be introduced, is outlined.     

Satellite measurements of solar X-ray flux and their use for interpretation of sudden ionospheric disturbances

Summary The apparatus for the reception and evaluation of the real-time telemetry (RTT) data on the X-ray flux, measured by the satellite Solrad-9, is briefly described. A comparison of the RTT data obtained with the data published by the authors of the experiment shows a good correlation of the data compared. The results of the comparison of our RTT data with SID data of the Panská Ves Observatory confirm many known facts concerning the response of the lower ionosphere to solar flares and, moreover, seem to support the idea of a less important role of X-rays in the lower ionosphere under slightly disturbed conditions.     

Analytical expression for fresnel volumes and interface fresnel zones of seismic body waves. Part 1: Direct and unconverted reflected waves

Summary Fresnel volumes, plane-sectional Fresnel zones and interface Fresnel zones of direct and unconverted reflected waves are studied. Exact analytical expressions for various parameters of Fresnel volumes and Fresnel zones are derived and discussed. Among others, these expressions are related to semi-axes of Fresnel zones, to overshooting and penetration distances, and to the off-ray shifts of Fresnel zones.