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31.
Prof. Dr. H. Troger Dipl. Ing. K. Zeman 《Archive of Applied Mechanics (Ingenieur Archiv)》1981,51(1-2):31-43
Übersicht Zur korrekten Modellbildung bei linearen, autonomen, dynamischen Systemen wird für die Ermittlung der richtigen Anzahl von Parametern die Theorie der Verzweigungsdiagramme von Matrizen von V. I. Arnold verwendet. Als Beispiele werden die Doppelpendel mit tangentialer und richtungstreuer Endlast behandelt.
Summary In order to obtain a correct model of a linear, autonomous, dynamical system with the right number of parameters the theory of bifurcation diagrams of matrices developed by V. I. Arnold is used. As examples two double pendula with a follower force respectively with dead loading are considered.相似文献
32.
The saturation magnetization value of the alloy was established as 2.0782 and 2.0148 T (± 0.5 mT), at 4 and 300 K, respectively. Compared with the spin-wave theory the value of the stiffness constant was obtained 2.15 × 1021 eV m2 and 1.9 × 1021 eV m2 at the helium and room temperature, respectively. The influence of the highest-order term on the temperature dependence of magnetization is small and can be neglected. Its value corresponds to the neutron diffraction measurements. 相似文献
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Progress in various fields of microscopy techniques brought up enormous possibilities to study the photosynthesis down to the level of individual pigment-protein complexes. The aim of this review is to present recent developments in the photosynthesis research obtained using such highly advanced techniques. Three areas of microscopy techniques covering optical microscopy, electron microscopy and scanning probe microscopy are reviewed. Whereas the electron microscopy and scanning probe microscopy are used in photosynthesis mainly for structural studies of photosynthetic pigment-protein complexes, the optical microscopy is used also for functional studies. 相似文献
35.
The Kováts retention indices of all 93 acyclic octenes on polydimethylsiloxane and squalane as stationary phases as well as their mass spectra were measured. The means of gas chromatography-mass spectrometry (GC-MS) were used for confirmation of GC identification as well as for mass spectrometric deconvolution of the majority of gas chromatographic unseparated isomeric octene peaks. The distinction between corresponding E and Z acyclic octenes, that is either difficult or even impossible by means of GC-MS, was obtained on the basis of larger temperature coefficients of retention indices for Z isomeric octenes than for corresponding E isomers. The retention data expressed as homomorphy factors were correlated with the degree of branching, position of double bond, and position of alkyl group with respect to the double bond of acyclic octenes, and the structure-retention relationships were formulated. The 81 acyclic octenes were identified in FCC gasoline. 相似文献
36.
Theoretical predictions and experimental observations show that a weak harmonic seed beam can control the process of generating multiple quadratic solitons in periodically poled KTiOPO4 by inputting only a fundamental beam. This all-optical switching does not depend on the relative phase of the input beams, an unusual property for such coherent solitons. 相似文献
37.
Dynamic properties of simple mechanical 1 DOF system containing soft stop is described and analyzed. The proposed general dynamical impact model respects the nonlinearity of the restoring contact force between solid bodies as function of deformation and velocity. It describes the real behavior of impacting system more exact than the piecewise linear model or the Kelvin–Voigt model and even model based on application of constant coefficient of restitution. Free and forced vibrations of system with Hertz's contact are investigated and domains of various types of impact motion, response curves and phase-plane trajectories are presented. 相似文献
38.
We show that every plane graph with maximum face size four in which all faces of size four are vertex‐disjoint is cyclically 5‐colorable. This answers a question of Albertson whether graphs drawn in the plane with all crossings independent are 5‐colorable. © 2009 Wiley Periodicals, Inc. J Graph Theory 64: 184–205, 2010 相似文献
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We address the problem of online route discovery for a class of graphs that can be embedded either in two or in three-dimensional space. In two dimensions we propose the class of quasi-planar graphs and in three dimensions the class of quasi-polyhedral graphs. In the former case such graphs are geometrically embedded in R2 and have an underlying backbone that is planar with convex faces; however within each face arbitrary edges (with arbitrary crossings) are allowed. In the latter case, these graphs are geometrically embedded in R3 and consist of a backbone of convex polyhedra and arbitrary edges within each polyhedron. In both cases we provide a routing algorithm that guarantees delivery. Our algorithms need only “remember” the source and destination nodes and one (respectively, two) reference nodes used to store information about the underlying face (respectively, polyhedron) currently being traversed. The existence of the backbone is used only in proofs of correctness of the routing algorithm; the particular choice is irrelevant and does not affect the behaviour of the algorithm. 相似文献