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951.
The set of acoustic signals of White-Sea white whales comprises about 70 types of signals. Six of them occur most often and constitute 75% of the total number of signals produced by these animals. According to behavioral reactions, white whales distinguish each other by acoustic signals, which is also typical of other animal species and humans. To investigate this phenomenon, signals perceived as vowel-like sounds of speech, including sounds perceived as a “bleat,” were chosen A sample of 480 signals recorded in June and July, 2000, in the White Sea within a reproductive assemblage of white whales near the Large Solovetskii Island was studied. Signals were recorded on a digital data carrier (a SONY minidisk) in the frequency range of 0.06–20 kHz. The purpose of the study was to reveal the perceptive and acoustic features specific to individual animals. The study was carried out using the methods of structural analysis of vocal speech that are employed in lingual criminalistics to identify a speaking person. It was demonstrated that this approach allows one to group the signals by coincident perceptive and acoustic parameters with assigning individual attributes to single parameters. This provided an opportunity to separate conditionally about 40 different sources of acoustic signals according to the totality of coincidences, which corresponded to the number of white whales observed visually. Thus, the application of this method proves to be very promising for the acoustic identification of white whales and other marine mammals, this possibility being very important for biology. 相似文献
952.
953.
A. S. Howard 《Physics of Atomic Nuclei》2004,67(11):2032-2040
The current status of direct dark matter searches by the Boulby Dark Matter Collaboration is presented with the latest result from the ZePLiN I liquid xenon detector. An upper limit in the interaction cross section per nucleon of ~1×10?6 pb for a WIMP mass of 100 GeV is found. Details of ZePLiN’s II and III—two future liquid xenon dark matter are presented. Extensive two-phase liquid-gas xenon prototype work has been undertaken and results of characterization studies are presented. The detector response to internal alpha and external gamma and neutron sources is shown. The potential discrimination power of the two-phase technique is displayed. Finally, prospects for the future dark matter search program are discussed. 相似文献
954.
955.
This paper firstly examines the value of optical bypass scheme in packet ring networks. An Integer Linear Program (ILP) formulation is presented and analytical results under different traffic patterns are given. 相似文献
956.
S. V. Zerkal' 《Computational Mathematics and Modeling》2003,14(2):149-159
The article examines the application of the particle method to numerical solution of the Cauchy problem for a quasi-linear system of first-order partial differential equations with discontinuous piecewise-constant initial conditions. A posterior estimate of the particle method error is derived for some shallow-water models. 相似文献
957.
S. P. Gavva 《Optics and Spectroscopy》2003,95(2):208-212
In the context of the theory of molecular vibrations, by applying the direct product operation of matrices, an equation for the vibrations of vibrationally excited molecules at combination and difference frequencies is obtained. From the solution of this equation, elements of vibration patterns and expressions that can be used for the study of changes in the molecular structural parameters and the coefficients of kinematic interactions are determined. The formulas obtained are applied to the calculation of the anharmonic electro-optical parameters of the molecules of water H2O and its two isotopes H2 17O and H2 18O. These calculations are performed in terms of the semiempirical quantum-chemical CNDO/2 method and by numerical differentiation of dipole moment functions by employing a cubic spline approximation. 相似文献
958.
Aminova G. A. Manuiko G. V. Bronskaya V. V. Bronskii S. N. Ismagilova A. I. D'yakonov G. S. 《Kinetics and Catalysis》2004,45(2):288-296
Based on an analysis of experimental results and published data, the main elementary steps of the anionic coordination polymerization of butadiene rubber on a cobalt-containing catalyst in the presence of ethylene were found, and a mathematical model of the periodic process at an optimum water content was developed. The molecular-weight characteristics of the process depending on ethylene concentration were studied with the use of this model. 相似文献
959.
Aleskovskii V. B. Klochev S. G. Misharev A. D. Romanychev A. I. 《Russian Journal of Applied Chemistry》2003,76(6):943-945
Conditions under which various kinds of carbon nanoparticles are obtained by thermal oxidative conversion of methane in chlorine in the temperature range 20-500°C were studied. The influence exerted by conditions of synthesis of nanodispersed carbon on the properties of its samples was analyzed. 相似文献
960.