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961.
Vakarchuk  S. B. 《Mathematical Notes》2002,72(5-6):615-619
In the Hardy space H p, (p1, 0< 1, H p,1 H p) we develop best linear approximation methods (previously studied by Taikov and Ainulloev) for the classes W(r,,) of analytic functions on the unit disk and calculate the exact values of linear, Gelfand, and informational n-widths of these classes.  相似文献   
962.
The notion of 3 0 -categoricity in linear orderings and Boolean algebras is examined. We provide a proof for the fact that there are uncountably many relatively 3 0 -categorical linear orderings, and furnish a proof of another fact which suggests that the (unrelatively) 3 0 -categorical linear orderings may be very difficult to classify. In stark contrast to these results for linear orderings, a complete classification of the relatively 3 0 -categorical Boolean algebras is given.  相似文献   
963.
A new nonlinear three-wave equation of the sixth order for pressure in a polydisperse gas-liquid mixture with bubbles of two sizes is obtained, and its stationary solutions are analyzed. The equation includes two nonlinear quadratic terms of different derivative orders. These terms are of fundamental importance for obtaining good correspondence between the solutions to this equation and the experimentally observed solitary waves in the form of two coupled solitons.  相似文献   
964.
We report an LD-end-pumped linearly-polarized continuous-wave (CW) Nd:YAP laser operating at 1341.4 nm. Making use of the plane-concave resonator (T = 2.4%) and the plane-plane resonator (T = 2.6%), we obtain linearly-polarized laser radiation at 1341.4 nm with a power of 3.15 and 2.86 W and corresponding optical slope efficiency of 18.4 and 17.5%, respectively. The effect of the laser oscillation mode on the output is analyzed. An experiment on the intra-cavity frequency doubling with an LBO crystal has been performed, and a laser power of 431 mW in one direction at 670.7 nm was obtained.  相似文献   
965.
The paper is mainly the review and generalization of the previous publications of the authors. It demonstrates that solution calorimetry method gives the opportunities of more detailed understanding of various aspects of intermolecular interactions in solution. We are assured that prerequisite to such an understanding is the successive analysis of various solute–solvent systems from the simplest ones which include alkanes as a solute or as a solvent to the most complex systems with solvent self‐association via hydrogen bonding. Particular findings discussed in this paper are (i) an inconspicuous contribution of electrostatic solute–solvent interaction to the solvation enthalpy and, accordingly, the dominating contribution of dispersion interactions for nonspecifically solvated solutes; (ii) new, very general method for the extraction of specific interaction enthalpy from the enthalpy of solvation; (iii) new method of determination of self‐association enthalpies for the solvents associated via hydrogen bonding; (iv) new method for determination of cooperative hydrogen bonding enthalpies of proton acceptors with associated species of alcohols; (v) the unique method of experimental determination of the hydrophobic effect enthalpy. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
966.
开挖过程的非线性理论分析   总被引:4,自引:2,他引:2  
本文从岩土介质力学非线性和变形破坏过程自组织非线性的角度对开挖过程岩土体非线性行为进行了探讨。以此为依据,分析了岩土从微观破坏、滑移面形成、直至整体变形破坏全过程的自组织发生机理,在此基础上,建立了伴随开挖过程岩土体变形破坏的非线性动力学描述方程。  相似文献   
967.
The main result of the paper is as follows.Theorem. Suppose that G(z) is an entire function satisfying the following conditions: 1) the Taylor coefficients of the function G(z) are nonnegative: 2) for some fixed C>0 and A>0 and for |z|>R0, the following inequality holds:
Further, suppose that for some fixed α>0 the deviation DN of the sequence xn={αn}, n=1, 2, ..., as N→∞ has the estimate DN=0(lnB N/N). Then if the function G(z) is not an identical constant and the inequality B+1<A holds, then the power series converging in the disk |z|<1 cannot be analytically continued to the region |z|>1 across any arc of the circle |z|=1. Translated fromMatematicheskie Zametki, Vol. 66, No. 4, pp. 540–550, October, 1999.  相似文献   
968.
The structure preserving rank reduction problem arises in many important applications. The singular value decomposition (SVD), while giving the closest low rank approximation to a given matrix in matrix L 2 norm and Frobenius norm, may not be appropriate for these applications since it does not preserve the given structure. We present a new method for structure preserving low rank approximation of a matrix, which is based on Structured Total Least Norm (STLN). The STLN is an efficient method for obtaining an approximate solution to an overdetermined linear system AX B, preserving the given linear structure in the perturbation [E F] such that (A + E)X = B + F. The approximate solution can be obtained to minimize the perturbation [E F] in the L p norm, where p = 1, 2, or . An algorithm is described for Hankel structure preserving low rank approximation using STLN with L p norm. Computational results are presented, which show performances of the STLN based method for L 1 and L 2 norms for reduced rank approximation for Hankel matrices.  相似文献   
969.
Real valued M-estimators in a statistical model 1 with observations are replaced by -valued M-estimators in a new model with observations where are regressors, is a structural parameter and a structural function of the new model. Sufficient conditions for the consistency of are derived, motivated by the sufficiency conditions for the simpler parent estimator The result is a general method of consistent estimation in a class of nonlinear (pseudolinear) statistical problems. If F has a natural exponential density exb( x ) then our pseudolinear model with u = (g o )–1 reduces to the well known generalized linear model, provided () = db()/d and g is the so-called link function of the generalized linear model. General results are illustrated for special pairs and leading to some classical M-estimators of mathematical statistics, as well as to a new class of generalized -quantile estimators.  相似文献   
970.
New oscillation and nonoscillation criteria are established for the equation
,where p :]1,+[ R is the locally integrable function. These criteria generalize and complement the well known criteria of E. Hille, Z. Nehari, A. Wintner, and P. Hartman.  相似文献   
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