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991.
Multi body system contains finite number of rigid bodies that are placed on each axis, which do not intersect each other. Derivatives of the linear momentum and angular momentum with respect to time by use mass moment vectors and vector rotators for pole and axis, are determined. A number of theorems are defined. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
992.
We consider a mixture of N ideal, polytropic gases. Each species is described by a distribution function fi(t, x, v, I) ≥ 0, 1 ≤ i ≤ N, defined on , and its evolution is governed by a Boltzmann-type equation. In order to recover the energy law of polytropic gases, the authors of [4] proposed a kinetic model in the framework of a weighted L1 space. Another approach has been developed in [3] in the context of polyatomic gases. Following this previous lead, our model provides a L2 framework in both variables v and I, to eventually perform a mathematical study of the diffusion asymptotics, as it was done in [2] for a model without energy exchange. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
993.
Aleksandra Delić 《PAMM》2013,13(1):349-350
We investigate the convergence of difference scheme for the time-fractional differential equation with fractional derivative of an order with the coefficient at the time derivative containing Dirac delta distribution. Convergence order of is proved. A numerical example demonstrates the theoretical results. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
994.
In the setting of generalized metric spaces, so called G-metric spaced introduced by Z. Mustafa and B. Sims in 2006, some fixed point results for mappings with contractive iterate at a point and common fixed point results for infinite family of self mappings will be presented. The results are generalizations of well known results in the metric space. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
995.
Derivative free methods for solving nonlinear equations of Steffensen’s type are presented. Using two self-correcting parameters, calculated by Newton’s interpolatory polynomials of second and third degree, the order of convergence is increased from 2 to 3.56. This method is used as a corrector for a family of biparametric two-step derivative free methods with and without memory with the accelerated convergence rate up to order 7. Significant acceleration of convergence is attained without any additional function calculations, which provides very high computational efficiency of the proposed methods. Another advantage is a convenient fact that the proposed methods do not use derivatives. Numerical examples are given to demonstrate excellent convergence behavior of the proposed methods and good coincidence with theoretical results.  相似文献   
996.
Let T be a complete, superstable theory with fewer than ${2^{\aleph_{0}}}$ countable models. Assuming that generic types of infinite, simple groups definable in T eq are sufficiently non-isolated we prove that ω ω is the strict upper bound for the Lascar rank of T.  相似文献   
997.
Despite of widely application of multivariate analysis in chemometrics, problem of resolving closely positioned components in the fluorescence spectra remained unsolved, thus limiting the usage of fluorescence spectroscopy in analytical purpose. In this paper we have described a novel procedure, adapted especially for the analysis of complex fluorescence spectra with multiple, closely positioned components’ maxima. The method was first tested on the simulated spectra and then applied on the spectra of proteins whose fluorophores have similar properties of both the excitation and the emission spectra. In this paper, simple but efficient modification of the method was applied. Instead of analyzing full size emission matrix (12 spectra), 9 spectra wide windows were analyzed, and 4 factors (greatest possible number of factors with physical meaning both for actin and simulated spectra) were extracted in each pass. Obtained factor scores were grouped by using the K-means algorithm. Groups of factor scores obtained from K-means algorithm were passed through the one more factor analysis (FA) in order to find one factor that represents each group. Our approach provides resolution of extremely closed spectral components, which is a vital data for protein conformation analysis based on fluorescence spectroscopy.  相似文献   
998.
The electronic bands appearing in the region 300–330 nm were produced in a low-pressure DC are with beryllium electrodes. The bands were obtained in the atmosphere of ordinary water vapour and heavy water vapour. From isotope shift studies, experimental conditions and the similarity with the bands of isoelectronic BeF, the emitting molecules were identified as BeOH and BeOD, respectively.  相似文献   
999.
High-resolution data of online chats are studied as a physical system in the laboratory in order to quantify collective behavior of users. Our analysis reveals strong regularities characteristic of natural systems with additional features. In particular, we find self-organized dynamics with long-range correlations in user actions and persistent associations among users that have the properties of a social network. Furthermore, the evolution of the graph and its architecture with specific kk-core structure are shown to be related with the type and the emotion arousal of exchanged messages. Partitioning of the graph by deletion of the links which carry high arousal messages exhibits critical fluctuations at the percolation threshold.  相似文献   
1000.
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