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891.
两个均匀分布总体标准差比的区间估计 总被引:1,自引:0,他引:1
考虑取两个均匀分布总体样本数不等时,两个均匀分布总体标准差比的估计,给出了两个均匀分布总体标准差比的区间估计. 相似文献
892.
Yu. A. Dabaghian 《Theoretical and Mathematical Physics》2008,156(1):996-1019
We discuss how to obtain exact and approximate distributions for various statistical characteristics of the spectra of quantum
graphs using previously found exact solutions of the spectral problem. We indicate the relation between the appearing spectral
decompositions and the theory of weakly dependent random variables and indicate the relation between the known limit theorems
for trigonometric sums and the universal statistical properties of the spectra of quantum chaotic systems.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 156, No. 1, pp. 38–66, July, 2008. 相似文献
893.
Alexandru V. Asimit 《Insurance: Mathematics and Economics》2008,43(3):407-411
We consider an extension of the classical compound Poisson risk model, where the waiting time between two consecutive claims and the forthcoming claim are no longer independent. Asymptotic tail probabilities of the reinsurance amount under ECOMOR and LCR treaties are obtained. Simulation results are provided in order to illustrate this. 相似文献
894.
Current models for pressure drop prediction of slug flow pneumatic conveying in a horizontal pipeline system assume some type of steady state conditions for prediction,which limits their capability for increased predictive accuracy relative to experimental data.This is partly because of the nature of slug flow pneumatic conveying system,which,as a dynamic system,never becomes stable.By utilising conservation of mass (airflow),a dynamic pressure analysis model is proposed on the basis of the derivative of the upstream pressure behaviour.The rate of air permeation through slug,one of the important factors in the conservation model,is expressed as a function of a slug permeability factor.Other factors such as slug velocity,slug length and the fraction of stationary layer were also considered.Several test materials were conveyed in single-slug tests to verify the proposed pressure drop model,showing good agreement between the model and experimental results. 相似文献
895.
D. Monzon-Hernandez A. N. Starodumov A. R. Boyain y Goitia V. N. Filippov V. P. Minkovich P. Gavrilovic 《Optics Communications》1999,170(4-6):241-246
Modal birefringence and stress distribution measurements in a single-mode double-clad Nd+3-doped fiber are reported. The contribution of different mechanisms, such as stress-induced birefringence, bending and core ellipticity, to the total birefringence is determined for a fiber wound onto a drum. A stress distribution pattern in the cross-section of the fiber is presented. The stresses are shown to be applied to a fiber core along the cladding minor axis. 相似文献
896.
It is applied the interpolation procedure to calculate the stationary probability distribution of colored-gain-noise model of a single-mode dye laser which operates above threshold with correlation time τ covering a very wide rang. By use of Stochastic Runge-Kutta Algorithm, it also has carried out numerical simulations of the steady-state properties. Comparing the results of the interpolation procedure and the unified colored-noise approximation with simulation results, the agreement between the results of the interpolation procedure and simulation results is much better than that of the unified colored-noise approximation when correlation time τ covers range from moderate to large. 相似文献
897.
吴永锋 《数学的实践与认识》2008,38(19)
利用概率方法给出了形如sum from k=1 to n(1/k)>π/4(sum from k=1 to n((-1)k-1Cnk)1/(k~1/2))与sum from k=1 to n(1/k)<2~(1/2)(sum from k=1 to n((-1)k-1Cnk)1/k2)1/2的组合不等式. 相似文献
898.
研究保费收取过程是一个随机过程的双险种风险模型,得出了Lundberg上界、最终破产概率、不破产所满足的微积分方程、索赔服从指数分布的不破产概率、有限时间不破产所满足的微积分方程. 相似文献
899.
900.
Purge-and-trap gas chromatography-mass spectrometry (PT-GC-MS) has become an accepted method for the analysis of trihalomethanes (THMs) in water. The purge-and-trap technique is based on an efficient transfer of volatile organic compounds from the liquid (contained in the purge chamber) to the gaseous phase by bubbling with an inert gas. The aim of this work was to study the purge system's efficiency by means of several consecutive purge cycles lasting 11 min each of the same liquid sample. The concentration range chosen of THMs was very wide [5-200 μg L−1]. The inert gas flow rate was 40 mL min−1, and experiments were performed at temperatures of 25, 35 and 50 °C. Bromoform (CHBr3), the least volatile compound, needed 19 cycles to be purged quantitatively at a concentration of 200 μg L−1 and only 7 cycles at 5 μg L−1 for a 25 mL sample at 25 °C. Chloroform (CHCl3), the most volatile compound, required 4 cycles to be fully extracted at 200 μg L−1 and 2 at 5 μg L−1. Finally, Novak's theoretical model, based on the distribution constant between gas and liquid phases, was used to correlate the THMs purging extraction data. 相似文献