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121.
Generalizing recent work of P. C. Matthews and A. L. Rukhin (Ann. Appl. Probab.3(1993), 454–466), we obtain the limit law of the largest interpoint Euclidean distance for a spherically symmetric multivariate sample of the Kotz distribution. While going through the proof, some errors in the reasoning given by Matthews and Rukhin are pointed out and corrected. 相似文献
122.
Paul Deheuvels 《Journal of multivariate analysis》1983,13(2):257-272
A new model for point processes is developed which assumes that the interarrival times are exponentially distributed and follow joint multivariate extreme value distributions. It is shown that such processes may arise via natural generating procedures, and that, under very weak assumptions, that they can be approximated as closely as desired by appropriate finite models. 相似文献
123.
Iterative Estimation of the Extreme Value Index 总被引:1,自引:0,他引:1
Samuel?MüllerEmail author Jürg?Hüsler 《Methodology and Computing in Applied Probability》2005,7(2):139-148
Let {Xn, n ≥ 1} be a sequence of independent random variables with common continuous distribution function F having finite and unknown upper endpoint. A new iterative estimation procedure for the extreme value index γ is proposed and one implemented iterative estimator is investigated in detail, which is asymptotically as good as the uniform minimum varianced unbiased estimator in an ideal model. Moreover, the superiority of the iterative estimator over its non iterated counterpart in the non asymptotic case is shown in a simulation study.AMS 2000 Subject Classification: 62G32Supported by Swiss National Science foundation. 相似文献
124.
A procedure for numerical investigation of nonaxisymmetric temperature fields and the elastic stress-strain state of laminated rotational bodies of cylindrically and rectilinearly orthotropic materials under nonisothermal loading is proposed. The deformation of orthotropic materials is described by the equations of anisotropic elasticity theory. The equations of state are written in the form of Hookes law for homogeneous materials, with additional terms which take into account the thermal deformation, changes in the mechanical properties of materials in the circumferential direction, and their dependence on temperature. A semianalytic finite-element method in combination with the method of successive approximations is used. An algorithm for numerical solution of the corresponding nonlinear boundary problem is elaborated, which is realized as a package of applied FORTRAN programs. Some numerical results are presented.Translated from Mekhanika Kompozitnykh Materialov, Vol. 40, No. 6, pp. 731–752, November–December, 2004. 相似文献
125.
Studies on dissociation energies of diatomic molecules using vibrational spectroscopic constants 总被引:4,自引:1,他引:3
New analytical expression and numerical approach are suggested to calculate dissociation energies De of diatomic molecular states using an extreme value method (EVM). Studies on some electronic states of OH, BH, N2, Br2, ClF and CO molecules show that the accuracy of the EVM dissociation energies depends on the number of correct vibrational constants used in the calculations. The convergence qualities of De are suggested to be an alternative physical criterion to measure the qualities of the various sets of vibrational constants from different literature for the same diatomic state. 相似文献
126.
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128.
针对光纤光栅应变传感器接收信号弱且信噪比低这一问题,提出了应用DSP技术来抑制噪声,提高Bragg峰值波长检测精度的方法.实验结果表明所设计的498阶Kaiser窗低通FIR数字滤波器能够显著提高光纤光栅应变传感器的信号检测精度.采用DSP技术可以较好地解决光纤光栅传感器的波长解调这一技术难题. 相似文献
129.
Alena Juríková Kornel Csach Jozef Miškuf Václav Ocelík 《Central European Journal of Physics》2007,5(2):177-187
Creep strain recovery and structural relaxation of the amorphous metallic glass Fe40Ni41B19 after longtime loading at different annealing temperatures below the glass transition temperature have been studied using
anisothermal differential scanning calorimetry (DSC) and dilatometry (TMA). It has been demonstrated that structural relaxation
effects depend on the stress-annealing temperature of the amorphous ribbon. The structural relaxation states of the amorphous
ribbon annealed at different temperatures under and without applied stress have been compared. The activation energy spectra
were calculated from the anisothermal dilatometric measurements using the modern method based on the Fourier transformation
technique. The influence of the annealing temperature on the shape of creep strain recovery spectra has been analyzed.
相似文献
130.