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161.
162.
赵月旭 《数学物理学报(B辑英文版)》2014,(2):301-312
It is well-known that the complete convergence theorem for i.i.d. random variables has been an active topic since the famous work done by Hsu and Robbins [6]. Chow [4]obtained a moment version of Hsu and Robbins series. However, the series tends to infinity whenever ∈ goes to zero, so it is of interest to investigate the asymptotic behavior of the series as ∈ goes to zero. This note gives some limit theorems of the series generated by moments for NA random variables. 相似文献
163.
In this paper, we consider a class of nonlocal stochastic Kuramoto–Sivashinsky equations driven by additive noises. Under some appropriate conditions, we investigate long time behavior, i.e., stability and growth bounds of the solutions to the equation. Finally, several examples are given to illustrate our results. 相似文献
165.
In this paper, we propose a globally hyperbolic regularization to the general Grad's moment system in multidimensional spaces. Systems with moments up to an arbitrary order are studied. The characteristic speeds of the regularized moment system can be analytically given and depend only on the macroscopic velocity and the temperature. The structure of the eigenvalues and eigenvectors of the coefficient matrix is fully clarified. The regularization together with the properties of the resulting moment systems is consistent with the simple one‐dimensional case discussed in 1. In addition, all characteristic waves are proven to be genuinely nonlinear or linearly degenerate, and the studies on the properties of rarefaction waves, contact discontinuities, and shock waves are included. © 2014 Wiley Periodicals, Inc. 相似文献
166.
相协样本半参数回归模型估计的矩相合性 总被引:1,自引:0,他引:1
考虑半参数回归模型Y(j) (xin,tin) =tinβ g(xin) e(j) (xin) ,1 ≤j≤m ,1 ≤i≤n .利用最小二乘法和权函数估计方法 ,定义 β ,g的估计量βm ,n和gm ,n(x) ,在负相依样本及较弱的条件下证明了这些估计的矩相合性 ,这些结论推广和改进了胡舒合 ( 1 997)关于独立情形的相应结论 . 相似文献
167.
Jingrui Zhang 《Acta Mechanica Sinica》2010,26(1):141-146
Studied in this paper are the attitude control law design and the output torque estimation problem of micro control moment gyros (MCMGs) for the agile satellites executing rapid attitude maneuver mission. An algorithm is proposed for estimating the output torques and the gimbal angular rates of MCMGs, which can help engineers to choose reasonable size for actuators so that the cost of satellite can be decreased. According to some special maneuver missions, a numerical example of attitude control system for a small satellite with MCMGs in pyramid configuration is studied, and the simulation results validate the proposed estimation algorithm. 相似文献
168.
Kororbov V. I. Krabs W. Skylar G. M. 《Journal of Optimization Theory and Applications》2000,107(1):51-68
We consider the linear model of a slowly rotating Timoshenko beam in a horizontal plane whose moment is controlled by the angular acceleration of the disk of the driving motor into which the beam is clamped. This work complements our previous results on the controllability of the beam from a position of rest into another position of rest; we give a method of construction of a piecewise constant control solving the problem. 相似文献
169.
S. Raymond J. Flouquet R. Calemczuk L. P. Regnault B. Fk P. Haen S. Kambe P. Lejay T. Fukuhara 《Physica B: Condensed Matter》2000,280(1-4):354-355
Results of neutron scattering and specific heat measurements are reported for two kinds of weak antiferromagnetic compounds corresponding to (i) the situation at the quantum critical point and (ii) the double magnetic transition observed in CeRu2Ge2. 相似文献
170.
Apparent correlations are found between the N-H chemical shifts of congeneric series of compounds and the dipole moments of the molecules, such as lactams and thiolactams, cyclic ureas and thioureas. When there is a high degree of correlation, either the N-H chemical shift or the dipole moment of the molecule can be used as an electronic parameter in correlating the biological activity with the chemical structure. In a series of substituted salicylaldehydes the Hammett σ constant gives better correlation with the biological activity than the O-H chemical shift. This is probably due to the anisotropic effect of the substituent besides the electronic effect. Other factors affecting the N-H chemical shift, e.g. intramolecular hydrogen-bonding of nitrosoureas and the deshielding effect of a benzene ring, in o-phenyleneureas are also presented. In spite of the limitations, the chemical shifts of many compounds can be obtained very easily, therefore, their uses in structure-activity correlations deserve further investigation. 相似文献