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941.
On the characterisation of paired monotone metrics 总被引:1,自引:1,他引:0
Paolo Gibilisco Tommaso Isola 《Annals of the Institute of Statistical Mathematics》2004,56(2):369-381
Hasegawa and Petz introduced the notion of paired monotone metrics. They also gave a characterisation theorem showing that
Wigner-Yanase-Dyson metrics are the only members of the paired family. In this paper we show that the characterisation theorem
holds true under hypotheses that are more general than those used in the above quoted references. 相似文献
942.
943.
Let A be a Weil algebra. The bijection between all natural operators lifting vector fields from m-manifolds to the bundle functor K
A
of Weil contact elements and the subalgebra of fixed elements SA of the Weil algebra A is determined and the bijection between all natural affinors on K
A
and SA is deduced. Furthermore, the rigidity of the functor K
A
is proved. Requisite results about the structure of SA are obtained by a purely algebraic approach, namely the existence of nontrivial SA is discussed. 相似文献
944.
945.
Nonlinear processes caused by the propagation of low-frequency and high-frequency acoustic pulses in an unbounded medium and the propagation of continuous waves in a ring resonator are theoretically studied on the basis of two hysteretic equations of state for media with imperfect elasticity. The profiles and parameters of pulses, the resonance curve and the Q factor of the resonator, and the ratio of the nonlinear resonance frequency shift to the nonlinear damping decrement are determined. For nonlinear wave processes in such media, the distinctive features that allow one to choose an appropriate hysteretic equation of state for analytically describing the experimental data are revealed. 相似文献
946.
947.
Richard P. Stanley 《Israel Journal of Mathematics》2004,143(1):317-339
We survey three recent developments in algebraic combinatorics. The first is the theory of cluster algebras and the Laurent
phenomenon of Sergey Fomin and Andrei Zelevinsky. The second is the construction of toric Schur functions and their application
to computing three-point Gromov-Witten invariants, by Alexander Postnikov. The third development is the construction of intersection
cohomology for nonrational fans by Paul Bressler and Valery Lunts and its application by Kalle Karu to the torich-vector of a nonrational polytope. We also briefly discuss the “half hard Lefschetz theorem” of Ed Swartz and its application
to matroid complexes.
Partially supported by NSF grant #DMS-9988459. 相似文献
948.
Composites were prepared from an aerosil and 4-n-alkyl-4'cyanobiphenyls with five to eight carbon atoms in the alkyl chain. Their high silica density of ∼7 g aerosil in 1 cm3 of liquid crystal (LC) allows the observation of the behaviour of a thin cyanobiphenyl layer (having nearly a monolayer structure) on the silica particles. The systems are investigated by dielectric spectroscopy (10-2-109 Hz) in a large temperature range (220-370 K). All the composites show a (main) relaxation process at frequencies much lower than the processes observed for the bulk LC that was assigned to the dynamics of the molecules in the surface layer. The temperature dependence of its characteristic frequencies obeys the Vogel-Fulcher-Tammann law, which is found to be typical for glass-forming liquids. The quasi two-dimensional character of the glass transition in the surface layer is discussed for the first time. At the nematic-to-isotropic transition temperature of the bulk, the composites show a continuous decrease of the characteristic frequencies as a function of the alkyl chain length, while the bulk LCs show the well known odd-even behaviour. The magnitude and temperature dependence of the slow relaxation process in the composites (molecules on an outer surface) agree with those of the same molecules confined to the nanopores of molecular sieves (internal surface). 相似文献
949.
Mieko Tanaka-Yamawaki 《Annals of the Institute of Statistical Mathematics》2003,55(2):437-446
Contrary to the common sense in economics and financial engineering, price fluctuations at very fine level of motion exhibit
various evidences against the efficient market hypothesis. We attempt to investigate this issue by studying extensive amount
of foreign currency exchange data for over five years at the finest level of resolution. We specifically focus on the proposed
stability in binomial conditional probabilities originally found in much smaller examples of financial time series. In order
to handle very large data, we have written an efficient program in C that automatically generates those conditional probabilities.
It is found that the stability is maintained for extremely large time duration that covers almost the entire period. Based
on the length of conditions for which the conditional probabilities are distinguishable each other, we identify the length
of memory being less than 3 movements. 相似文献
950.
Mechanisms of the self-organization of nanosystems at the condensation of the extremely weak steady flows of copper vapors
obtained in magnetron sputtering in an ultrapure argon are studied. It is shown that the free-energy minimization near equilibrium
condensation creates prerequisites for the self-organization of statistically homogeneous layers of nanoclusters and determines
the transition to the formation of nanosystems in the form of fractal networks.
Original Russian Text ? V.I. Perekrestov, A.S. Kornyushchenko, Yu.A. Kosminskaya, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ
i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 12, pp. 879–883. 相似文献