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991.
正负系数中立型差分方程的全局吸引性 总被引:1,自引:0,他引:1
A neutral difference equation with positive and negative coefficients△(xn-cnxn-k) pnxn-l-qnxn-r=0,n=0,1,2.…,is considered and a sufficient condition for the global attractivity of the zero solution of this equation is obtained, which improves and extends the all known results in the literature. 相似文献
992.
We consider the determination of portfolio processes yielding the highest worst-case bound for the expected utility from final wealth if the stock price may have uncertain (down) jumps. The optimal portfolios are derived as solutions of non-linear differential equations which itself are consequences of a Bellman principle for worst-case bounds. A particular application of our setting is to model crash scenarios where both the number and the height of the crash are uncertain but bounded. Also the situation of changing market coefficients after a possible crash is analyzed. 相似文献
993.
I. V. Bodnar A. G. Karoza E. A. Kudritskaya A. G. Smirnova 《Journal of Applied Spectroscopy》1997,64(2):279-282
The IR reflection spectra of In2S3, CuIn5S8, AgIn5S8 compounds with a spinel structure are investigated. Using the DA-K-K method, we determined the frequencies of longitudinal
and transverse phonons, attenuation coefficients of phonons, and IR intensities, as well as the dielectric constants ε0 and ε∞.
Belarusian State University of Information Science and Radioelectronics, 6, P. Brovka St., Minsk 220600, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 2, pp. 263–265, March–April, 1997. 相似文献
994.
Aaldert Compagner 《Journal of statistical physics》1991,63(5-6):883-896
The meaning of randomness is studied for the simple case of binary sequences. Ensemble theory is used, together with correlation coefficients of any order. Conservation laws for the total amount of correlation are obtained. They imply that true randomness is an ensemble property and can never be achieved in a single sequence. The relation with entropy is discussed for different ensembles. Well-tempered pseudorandom sequences turn out to be suitable sources of random numbers, and practical recipes to generate them for use in large-scale Monte Carlo simulations are found. 相似文献
995.
提出了一种将任意入射波束因子用矢量波函数展开的方法,根据波束在球坐标系中的展开形式,以及球谐矢量函数与非球坐标系的波矢量函数之间的关系,推导出任意入射波束在相应坐标系中的波束因子的理论表述形式.以椭球坐标系为例,介绍了将离轴的入射波束,用椭球矢量波函数展开的波束因子求解方法,此方法还可应用于柱坐标、椭柱坐标系中波束因子的求解,为研究粒子对任意入射波束的散射打下了基础.
关键词:
波束因子
广义米理论
光散射 相似文献
996.
997.
光学薄膜热膨胀系数的研究 总被引:1,自引:1,他引:0
光热位移偏转技术结合横向光热偏转技术可用于研究薄膜样品的热膨胀系数.本文以SiO_2、TiO_2、ZrO_2、MgF_2、ThF4等单层光学薄膜为例.报道相关的实验方法及实验结果. 相似文献
998.
Derek G. Leaist 《Journal of solution chemistry》1987,16(10):805-812
A modified Harned conductimetric procedure has been used to measure binary diffusion coefficients at 25°C for aqueous sodium and potassium salts of the protein bovine serum albumin (M
n
BSA; M=Na+ or K+; n=2 to 23). The condition of electroneutrality requires that the BSA ions diffuse at the same speed as the relatively mobile sodium or potassium counterions. Consequently, the protein ions diffuse 3 to 8 times more rapidly than the isoionic protein diffuses. An approximate analysis of counterion-accelerated diffusion of high molecular weight solutes is presented which shows that the increase in diffusivity with the number of counterions is a thermodynamic effect brought about by an increase in the free energy gradient of the solutes. 相似文献
999.
T. K. Lim 《Journal of solution chemistry》1987,16(1):11-20
In present work, a new method is developed from which activity coefficients for both electrolytes in admixture can be obtained simultaneously from the fitting of experimental activity coefficients of one of the electrolyte. The calculated results for the system HCl+KCl at 25°C are reported and discussed. 相似文献
1000.
Solubilities of carbon dioxide in aqueous ethanol solutions, determined at 15, 20, 25, 30 and 35°C at atmospheric pressure, show a minimum at each temperature. Thermodynamics functions for the solution process were calculated and compared with the predictions of the Pierotti gas solubility theory. The abnormal behavior of these solutions is demonstrated. 相似文献