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Quality control systems for satellite laser ranging (SLR) observations have been developed at a number of analysis institutes worldwide, using various software packages of precise orbit determination and data analysis. Satellite laser range observations, primarily from the two LAGEOS satellites but also from other satellites in low-Earth orbits and up to GNSS altitude, are being processed on a sub-daily to weekly basis. The generated quality control reports are widely used to detect various kinds of problems and quickly provide anomalous information to laser ranging stations. They have been effective in shortening the time to return to normal operations when anomalous data are detected and in quantifying the performance of laser ranging stations. Consequently, a rapid feedback loop has now been incorporated in the modern SLR operation.

Consistent and homogeneous long-time series of the space geodetic techniquesGlobal Positioning System (GPS), Satellite Laser Ranging (SLR), andVery Long Baseline Interferometry (VLBI) provide the basis for thecombination efforts of GGOS-D. For a consistent combination, thedefinition of common standards for parameterization and modeling isessential. These standards and the technique-specific processingoptions of all individual GPS, SLR, and VLBI solutions as well asthe combined SLR and VLBI solutions are discussed.

This paper presents the results of different methods that have been applied to investigate the strength of SLR observations to realize the scale and origin of the terrestrial reference system. In this context the effect of the network geometry and the satellite altitude has been studied by analysing the covariance matrix of the datum parameters. Furthermore, the time series of the scale and translation parameters of weekly SLR network solutions were analysed from 1993 until 2007 and the effect of range bias estimation has been investigated

A simulation and analysis program system for the design and the analysis of catalytic fixed-bed reactors was selected for parallel implementation. The minimization subroutine of this program system was adapted for parallel computation both at the algorithm level and at the program level. The algorithm follows the Simplex method of Nelder and Mead and allows optimization of the reaction parameters minimizing a least-squares-function. The computation of this minimization problem was prepared for the Erlan-gen-General-Purpose-Array (EGPA) multiprocessor-system.

The most precise space geodetic techniques for the realization of global terrestrial reference systems are VLBI, SLR and GPS. We focus on the contribution of these techniques to the determination of the vertical component. We discuss the strengths and weaknesses of each of the technique regarding the height determination as well as the effect of systematic errors. The quality of the ITRF (especially with respect to the vertical component) is assessed. Finally VLBI, SLR and GPS time series of position estimates are used to discuss the time—dependent stability of the solutions.

This paper deals with the estimation of geocenter variations on the basis of SLR data to LAGEOS 1 and 2. The paper describes the SLR data analysis with the DGFI software DOGS. We computed a combined LAGEOS 1 & 2 solution, and in addition two separate solutions using the data of both satellites independently. For the estimation of geocenter variations we applied a geometric and an analytic method. The results obtained from these different approaches were used to assess the accuracy and consistency of the geocenter determination. Finally we compared our estimates with other space geodetic and geophysically derived results. We found a good agreement for the annual amplitudes and phases, whereas the semiannual signals differ significantly.

Das Rechtsschutzbedurfnis fur eine Klage, fur einen Sachantrag ist klar zu trennen von der Berechtigung des materiellen Klagebegehrens. So stellt z.B. die Sittenwidrigkeit der Anspruchsgrundlage1 oder der Misbrauch eines Anfechtungsrechts2 nur die Begrundetheit der Klage, nicht bereits ihre Zulassigkeit in Frage.

This paper presents the results of the first steps to set up a rigorous adjustment of a European network including GPS, SLR and VLBI data by combining these on the normal equation level. The network consists of about 20 permanently operating GPS stations, of which ten provide colocations with SLR systems, and seven stations are colocated with VLBI.

It is scetched how the inductive assertion method of Floyd/Hoare and the termination proof method of Floyd/Manna can be used for the analysis of reachability sets for arbitrary initial transition systems.

Inorganic sulfur compounds in various reduced stages serve as essential electron donors for a variety of microorganisms. The photosynthetic sulfur bacteria depend on light as their energy source in an anaerobic environment (photolithotrophs). The chemolithotrophs lack chlorophyll and use the inorganic reduced sulfur as the source of energy and electrons under aerobic conditions (Fig. 1).

The net representation of the alternating bit protocol given in newsletter 7 of the special interest group on Petri nets and related system models (Feb. 1981) is proved “correct” by using assertion systems.

Survey on the reachability problem for VAS. Kosaraju's decision procedure with comments on complexity and an example.

The paper presents a high level Petri net (HLPN) specification of an algorithm for global termination detection of a system of parallel processes. The correctness is proved using invariants and an assertion system.

Nachdem die 1912 aufgestellte Debyesche Theorie (11) der molekularen Dipole in ihren Grundlagen geklart war, zeigte sich, das man damit fur das Gebiet der molekularen Strukturforschung ein auserst wirksames Werkzeug in die Hand bekommen hatte. Dielektrische Untersuchungen an Gasen und verdunnten Losungen brachten Aufklarung uber Ladungsverteilung, Symmetrie und Kerngerust von Molekulen. Die Regel von der Additivitat der Partialmomente fuhrte zu Valenzwinkelmessungen. Verfeinerungen der Versuche wiesen auf Induktionseffekte und innermolekulare Wechselwirkungen hin, bestatigten freie und gehemmte Rotation von Atomgruppen (13, 29, 107), und in neuerer Zeit ergaben sich sogar aus Messungen an konzentrierten Losungen und an reinen polaren Flussigkeiten Ausblicke auf Assoziationsmechanismus und Flussigkeitsstruktur, also Aussagen uber zwischenmolekulare Wechselwirkungen (78, 90).