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101.
Martin Breza 《Czechoslovak Journal of Physics》1992,42(2):201-207
The electronic structure of YBa2Cu3Ox (x=6 and 7) is investigated using the CNDO molecular orbital method. Electronic structures of model clusters [Cu3O10]–15, [Ba8Cu3O10]+1, [Y8Cu3O10]+9 of the non-superconducting (x=6) and [Cu3O12]–17, [Ba8Cu3O12]–1, [Y8Cu3O12]+7 of the superconducting (x=7) phases are compared. Y and Ba layers cause a considerable electron density transfer from the central Cu(1) region. 相似文献
102.
Martin E. V. Pedersen Lars S. Rishøj Henrik Steffensen Sanshui Xiao Niels Asger Mortensen 《Optical and Quantum Electronics》2007,39(10-11):903-911
Slow-light enhanced optical detection in liquid-infiltrated photonic crystals is theoretically studied. Using a scattering-matrix approach and the Wigner–Smith delay time concept, we show that optical absorbance benefits both from slow-light phenomena as well as a high filling factor of the energy residing in the liquid. Utilizing strongly dispersive photonic crystal structures, we numerically demonstrate how liquid-infiltrated photonic crystals facilitate enhanced light–matter interactions, by potentially up to an order of magnitude. The proposed concept provides strong opportunities for improving existing miniaturized absorbance cells for optical detection in lab-on-a-chip systems. 相似文献
103.
Signal classification through multifractal analysis and complex domain neural networks 总被引:1,自引:0,他引:1
W. Kinsner Vincent Cheung K. Cannons J. Pear T. Martin 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2006,36(2):196-203
This paper describes a system capable of classifying stochastic self-affine nonstationary signals produced by nonlinear systems. The classification and the analysis of these signals are important because these are generated by many real-world processes. The first stage of the signal classification process entails the transformation of the signal into the multifractal dimension domain, through the computation of the variance fractal dimension trajectory (VFDT). Features can then be extracted from the VFDT using a Kohonen self-organizing feature map. The second stage involves the use of a complex domain neural network and a probabilistic neural network to determine the class of a signal based on these extracted features. The results of this paper show that these techniques can be successful in creating a classification system which can obtain correct classification rates of about 87% when performing classification of such signals without knowing the number of classes. 相似文献
104.
Martin Traizet 《Commentarii Mathematici Helvetici》2004,79(4):798-825
We prove a balancing condition for weak limits of
families of embedded
minimal surfaces of finite total curvature. We use it to
prove compactness theorems for certain families of minimal
surfaces. 相似文献
105.
106.
107.
Let G be a d‐regular graph G on n vertices. Suppose that the adjacency matrix of G is such that the eigenvalue λ which is second largest in absolute value satisfies λ = o(d). Let Gp with p = α/d be obtained from G by including each edge of G independently with probability p. We show that if α < 1, then whp the maximum component size of Gp is O(log n) and if α > 1, then Gp contains a unique giant component of size Ω(n), with all other components of size O(log n). © 2003 Wiley Periodicals, Inc. Random Struct. Alg., 2004 相似文献
108.
109.
Martin R. Bridson Charles F. Miller III 《Proceedings of the American Mathematical Society》2004,132(1):59-65
We give examples of direct products of three hyperbolic groups in which there cannot exist an algorithm to decide which finitely presented subgroups are isomorphic.
110.
Gaven J. Martin Volker Mayer 《Transactions of the American Mathematical Society》2003,355(11):4349-4363
We consider rigidity phenomena for holomorphic functions and then more generally for uniformly quasiregular maps.