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161.
Jürgen Kurths M. Carmen Romano Marco Thiel Grigory V. Osipov Mikhail V. Ivanchenko István Z. Kiss John L. Hudson 《Nonlinear dynamics》2006,44(1-4):135-149
We present two different approaches to detect and quantify phase synchronization in the case of coupled non-phase coherent
oscillators. The first one is based on the general idea of curvature of an arbitrary curve. The second one is based on recurrences
of the trajectory in phase space. We illustrate both methods in the paradigmatic example of the R?ssler system in the funnel
regime. We show that the second method is applicable even in the case of noisy data. Furthermore, we extend the second approach
to the application of chains of coupled systems, which allows us to detect easily clusters of synchronized oscillators. In
order to illustrate the applicability of this approach, we show the results of the algorithm applied to experimental data
from a population of 64 electrochemical oscillators. 相似文献
162.
163.
N. M. Zoumakis 《Il Nuovo Cimento C》1992,15(2):247-250
Summary An approximate relationship between the gradient, Ri, and the bulk Richardson number, Rib, for unstable atmospheric conditions, is suggested. The proposed relation shows much better agreement with the estimation
provided by a numerical iterative method than the usual approximations suggested by Louis and Byun. 相似文献
164.
M.N. Kotby S.R. El-Sady S.E. Basiouny Y.A. Abou-Rass M.A. Hegazi 《Journal of voice》1991,5(4):316-320
The management of voice disorders may follow one of four approaches: surgical, pharmacological, technical aid, and/or voice therapy. The latter approach offers a wide variety of techniques, each based on certain theoretical beliefs. One of these techniques is the Smith Accent Method. The principles and goals of the Accent Method are presented. The results of its application are discussed. This technique proved effective for cases of functional voice disorders, vocal nodules, and some degrees of vocal fold paralysis. 相似文献
165.
V.I. Marakhonov N.A. Rogachev E.I. Terukov J.T. Ishkalov I.N. Trapeznikova 《Physica B: Condensed Matter》1991,170(1-4):571-573
Magnetron assisted silane decomposition (MASD) is proposed as a method for deposition of a-Si:H and its alloys. In this method a silane containing gas mixture is passed through the magnetron plasma near a target and decomposed there. The deposition rate in the case of the c-Si target is increased 3 times compared to magnetron sputtering and film properties are changed. a-SiSn:H is obtained with a Sn target. 相似文献
166.
A 480 L evacuable reaction chamber, equipped with FT-IR spectroscopy on-line and ion chromatography off-line, has been used to study the gas phase reaction between the nitrate radical, NO3, and the reduced organic sulphur compounds CH3CH2SH, (CH3CH2)2S, (CH3CH2)2S2, and CH3CH2SCH3 in air. The products CH3CH2SO3H, SO2, H2SO4, CH3CHO, and CH3CH2ONO2 were identified and quantified in the reactions of the first three compounds, CH3CH2SH, (CH3CH2)2S, and (CH3CH2)2S2. The reaction products were CH3CH2SO3H, CH3SO3H, SO2, H2SO4, CH3CHO, and CH2O in the reaction of CH3CH2SCH3. On the basis of identified reaction products and intermediates observed in the infrared spectra, mechanisms are proposed for the reactions between the NO3 radical and the four reduced organic sulphur compounds. The results of this study, together with those from previous experiments performed in this laboratory on CH3SCH3, CH3SH, and CH3SSCH3 lead to the conclusion that all these species, in the reaction with the NO3 radical, follow a similar degradation mechanism producing SO2, H2SO4, R? SO3H, R? CHO, and R? CH2ONO2, as the main reaction products. The inital step of the reaction of NO3 with R? S? R and R? S? H type (R = CH3, CH2CH3) reduced organic sulphur compounds was found to be H-atom abstraction, probably after the formation of an initial adduct. For the reaction between NO3 and R? S? S? R type compounds, evidence for an addition-decomposition reaction, as the initial steps, was obtained. R? S·, R? S(O)·, and R? S(O)2· appear to be formed as intermediates in all the reactions. © John Wiley & Sons, Inc. 相似文献
167.
V. N. Shander 《Functional Analysis and Its Applications》1992,26(1):55-56
Scientific Research Institute for Systems Studies, Academy of Sciences of the USSR. Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 26, No. 1, pp. 69–71, January–March, 1992. 相似文献
168.
We generalize a method for determination of time scales of nonstationary diffusion in a one-dimensional medium. The time of relaxation to a stationary non-equilibrium density of substance in a system with a source, a sink, and an arbitrary potential profile are obtained and studied in detail. A few specific examples are considered. 相似文献
169.
170.