Zur Behandlung von Zufallssehwingungen mechanischer Bauteile infolge mehrfachkorrelierter stochastischer Erregungen

Übersicht Neben der zur Behandlung mechanischer Zufallsschwingungen gebräuchlichen Spektralmethode wird die Kovarianzanalyse mit ihrer vorteilhaften Schwingungsvarianzberechnung vorgestellt. Es wird gezeigt, daß diese Methode auch für mehrfachkorrelierte, in der Natur meßbare Zufallsvorgänge genutzt werden kann. Am Beispiel eines winderregten Turmtragwerks wird ein Vergleich zwischen Spektralmethode und Kovarianzanalyse gezogen.

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On the analysis of random vibrations caused by multi-correlated excitations

Summary In comparison with the wellknown method for calculating variances of random vibrations using spectral densities the method of the covariance analysis is illustrated. The efficiency of this method is demonstrated for multi-correlated random excitations which can be found in nature. An example with windinfluenced vibrations of a televisiontower is discussed for both methods.

     

Zur quantitativen Bestimmung von Blaus?ure in pflanzlichen und tierischen Geweben

Ohne Zusammenfassung     

A note on dominating sets and average distance

We show that the total domination number of a simple connected graph is greater than the average distance of the graph minus one-half, and that this inequality is best possible. In addition, we show that the domination number of the graph is greater than two-thirds of the average distance minus one-third, and that this inequality is best possible. Although the latter inequality is a corollary to a result of P. Dankelmann, we present a short and direct proof.     

Revealing noncovalent interactions in quantum crystallography: Taurine revisited

The charge density distribution in taurine (2‐aminoethane‐sulfonic acid) is further studied with the molecular orbital occupation number refinement scheme. The recently proposed NCIPLOT scheme (Johnson et al., J. Am. Chem. Soc. 2010, 132, 6498) is applied to visualize the noncovalent interactions from experimentally refined charge densities. Herein, we demonstrate the evolution of the reduced density gradient isosurface during the charge density refinement process. © 2012 Wiley Periodicals, Inc.