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排序方式: 共有431条查询结果,搜索用时 15 毫秒
41.
This article uses the shrinking projection method introduced by Takahashi, Kubota and Takeuchi to propose an iteration algorithm for a countable family of Bregman multi-valued quasi-nonexpansive mappings in order to have the strong convergence under a limit condition in the framework of reflexive Banach spaces. We apply our results to a zero point problem of maximal monotone mappings and equilibrium problems in reflexive Banach spaces. The results presented in the article improve and extend the corresponding results of that found in the literature. 相似文献
42.
The paper outlines a procedure to derive the canonical system of equations of the classical theory of thin shells using Reissner’s
variational principle and partial variational principles. The Hamiltonian form of the Reissner functional is obtained using
Lagrange multipliers to include the kinematical conditions that follow from the Kirchhoff-Love hypotheses. It is shown that
the canonical system of equations can be represented in three different forms: one conventional form (five equilibrium equations)
and two forms that are equivalent to it. This can be proved by reducing them to the same system of three equations. For problems
with separable active and passive variables, partial variational principles are formulated
__________
Translated from Prikladnaya Mekhanika, Vol. 43, No. 10, pp. 99–107, October 2007. 相似文献
43.
Fatemeh Shakeri Mehdi Dehghan 《Numerical Methods for Partial Differential Equations》2011,27(5):1055-1071
This article presents a technique based on the hybrid Legendre tau‐finite difference method to solve the fourth order wave equation which arises in the elasto‐plastic‐microstructure models for longitudinal motion of an elasto‐plastic bar. Illustrative examples and numerical results obtained using new technique demonstrate that the proposed approach is efficient in treating longitudinal equation of ealsto‐plastic bar. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 1055–1071, 2011 相似文献
44.
Frédéric Cadet 《光谱学快报》2013,46(5):937-951
Abstract Quantitative determination from infrared spectra still faces problems that are not completely resolved to date. One of these problems is the deformation of baselines. We have tested the Legendre baseline correction method by subtracting from a spectrum the low-degreed terms from a Legendre polynomial function which is obtained by the decomposition of the spectrum. As opposed to the filtered spectra with n=0 which remained very similar to the original spectra, the filtered spectra, as from n=2, exhibit a great amount of distorsion. This result suggests that it is as from n=2, that the terms that are meaningful to the signal (not just to baseline), are to be substracted. Mathematical methods such as Principal Component Analysis and Principal Component Regression are used to analyse quantitatively components from biological samples. The thus predicted sucrose content values for values of n that range between 0 and 8 (n={0, 2, 4, 6, 8}) show that the best results are obtained for n=4. The mean and standard deviation values of the difference between reference and predicted values varies between 8.5 × 10?2 and 6.6 × 10?2 and between 0. 224 and 0. 195 respectively; these values are minimum when the n=4 term is subtracted from the spectra. This processing hence, sensibly improves the quantification of components from Mid-FTIR spectra of biological solutions. This procedure would be interesting in cases where the precision of quantitative measures is essential. 相似文献
45.
We discuss a subtlety involved in the calculation of multifractal spectra when these are expressed as Legendre-Fenchel transforms of functions analogous to free energy functions. We show that the Legendre-Fenchel transform of a free energy function yields the correct multifractal spectrum only when the latter is wholly concave. If the spectrum has no definite concavity, then the transform yields the concave envelope of the spectrum rather than the spectrum itself. Some mathematical and physical examples are given to illustrate this result, which lies at the root of the nonequivalence of the microcanonical and canonical ensembles. On a more positive note, we also show that the impossibility of expressing nonconcave multifractal spectra through Legendre-Fenchel transforms of free energies can be circumvented with the help of a generalized free energy function, which relates to a recently introduced generalized canonical ensemble. Analogies with the calculation of rate functions in large deviation theory are finally discussed.
PACS numbers: 05.45.Df, 64.60.Ak, 65.40.Gr 相似文献
46.
Frank E. Harris 《International journal of quantum chemistry》2004,97(5):908-913
47.
Ahlswede Rudolf Khachatrian Levon H. Mauduit C. Sárközy A. 《Periodica Mathematica Hungarica》2003,46(2):107-118
In earlier papers finite pseudorandom binary sequences were studied, quantitative measures of pseudorandomness of them were
introduced and studied, and large families of “good” pseudorandom sequences were constructed. In certain applications (cryptography)
it is not enough to know that a family of “good” pseudorandom binary sequences is large, it is a more important property if
it has a “rich”, “complex” structure. Correspondingly, the notion of “f-complexity” of a family of binary sequences is introduced. It is shown that the family of “good” pseudorandom binary sequences
constructed earlier is also of high f-complexity. Finally, the cardinality of the smallest family achieving a prescibed f-complexity and multiplicity is estimated.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
48.
D. B. Hunter 《Numerical Algorithms》1995,10(1):41-49
A method of evaluating Legendre functions of the second kind by applying the trapezoidal rule to Heine's integral representation is described. An error analysis is given, and some numerical results are obtained.Dedicated to Professor Luigi Gatteschi 相似文献
49.
Shifted Legendre polynomial functions are employed to solve the linear-quadratic optimal control problem for lumped parameter system. Using the characteristics of the shifted Legendre polynomials, the system equations and the adjoint equations of the optimal control problem are reduced to functional ordinary differential equations. The solution of the functional differential equations are obtained in a series of the shifted Legendre functions. The operational matrix for the integration of the shifted Legendre polynomial functions is also introduced in the simulation step in order to simplify the computational procedure. An illustrative example of an optimal control problem is given, and the computational results are compared with those of the exact solution. The proposed method is effective and accurate. 相似文献
50.
We prove an extension theorem for ultraholomorphic classes defined by so-called Braun–Meise–Taylor weight functions ω and transfer the proofs from the single weight sequence case from V. Thilliez to the weight function setting. We are following a different approach than the results obtained in a recent paper by the authors, more precisely we are working with real methods by applying the ultradifferentiable Whitney-extension theorem. We are treating both the Roumieu and the Beurling case, the latter one is obtained by a reduction from the Roumieu case. 相似文献