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201.
E. M. El-Kholy El-Said R. Lashin Salama N. Daoud 《Proceedings Mathematical Sciences》2007,117(3):293-300
In this paper we introduce a new type of folding called equi-Gaussian curvature folding of connected Riemannian 2-manifolds.
We prove that the composition and the cartesian product of such foldings is again an equi-Gaussian curvature folding. In case
of equi-Gaussian curvature foldings, f: M → P
n
, of an orientable surface M onto a polygon P
n
we prove that
and we generalize (iii) for #nT
2. 相似文献
((i)) |
((ii)) |
((iii)) |
202.
203.
We consider the Hankel determinant generated by the Gaussian weight with two jump discontinuities. Utilizing the results of Min and Chen [Math. Methods Appl Sci. 2019;42:301‐321] where a second‐order partial differential equation (PDE) was deduced for the log derivative of the Hankel determinant by using the ladder operators adapted to orthogonal polynomials, we derive the coupled Painlevé IV system which was established in Wu and Xu [arXiv: 2002.11240v2] by a study of the Riemann‐Hilbert problem for orthogonal polynomials. Under double scaling, we show that, as , the log derivative of the Hankel determinant in the scaled variables tends to the Hamiltonian of a coupled Painlevé II system and it satisfies a second‐order PDE. In addition, we obtain the asymptotics for the recurrence coefficients of orthogonal polynomials, which are connected with the solutions of the coupled Painlevé II system. 相似文献
204.
205.
206.
In this paper,we obtain some asymptotic behavior results for solutions to the prescribed Gaussian curvature equation.Moreover,we prove that under a con-formal metric in R2,if the total Gaussian curvature is 4π,the conformal area of R2 is finite and the Gaussian curvature is bounded,then R2 is a compact C1,α surface after completion at ∞,for any α ∈(0,1).If the Gaussian curvature has a Holder decay at in-finity,then the completed surface is C2.For radial solutions,the same regularity holds if the Gaussian curvature has a limit at infinity. 相似文献
207.
A Gaussian distribution model was developed to examine the field-induced performance of anisotropic magnetorheological elastomers. The developed model was based on the assumption that the iron particles in magnetorheological elastomers aggregate into a large number of parallel body-centered tetragonal structure columns whose length obeys the Gaussian distribution. By using multi-pole approximation with local field effect and taking into account the nonlinearity and saturation of particle magnetization, the field-induced shear modulus was calculated as a function of distribution and dimension of the particle structures, the external magnetic field and the dynamic shear strain. Compared with other modes as well as the published experimental results, this model shows a remarkable improvement in accurately predicting the behavior of the magnetorheological elastomers. 相似文献
208.
Estimating the Parameters of a Fractional Brownian Motion by Discrete Variations of its Sample Paths 总被引:1,自引:0,他引:1
This paper develops a class of consistent estimators of the parameters of a fractional Brownian motion based on the asymptotic
behavior of the k-th absolute moment of discrete variations of its sampled paths over a discrete grid of the interval [0,1]. We derive explicit
convergence rates for these types of estimators, valid through the whole range 0 < H < 1 of the self-similarity parameter. We also establish the asymptotic normality of our estimators. The effectiveness of
our procedure is investigated in a simulation study.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
209.
Gaussian elimination with partial pivoting achieved by adding the pivot row to the kth row at step k, was introduced by Onaga and Takechi in 1986 as means for reducing communications in parallel implementations. In this paper it is shown that the growth factor of this partial pivoting algorithm is bounded above by n <#60; 3
n–1, as compared to 2
n–1 for the standard partial pivoting. This bound n, close to 3
n–2, is attainable for class of near-singular matrices. Moreover, for the same matrices the growth factor is small under partial pivoting.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
210.
Gaussian polynomials are used to define bases with good multiplicative properties for the algebra K
*(K) of cooperations in K-theory and for the invariants under conjugation. 相似文献