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131.
本文研究了当n趋于无穷大时,关于K2+Tm和完全图Kn的Ramsey数的渐近上界,以及r(K2+Tm,Kn)和r(K1+Tm,Kn)的渐近关系.利用李雨生等人所给出的一个独立数的下界公式,给出了r(K4,Kn)和r(Kk-c,Kn)的渐近上下界,推广了李雨生等人所给出的r(K1+Tm,Kn)的下界. 相似文献
132.
133.
广义正交基是Hilbert 空间中正交基的一个自然推广. 本文首先给出一个广义正交基存在的较弱的充要条件; 然后研究广义正交基的性质, 特别地, 得到广义正交基版本的一些有关正交基的经典性质, 如广义正交基的Bessel 等式和不等式等. 作为广义正交基的一个应用, 本文给出广义Riesz 基的一些新刻画. 最后本文讨论广义框架的冗余问题. 相似文献
134.
We extend in several directions a complete convergence theorem for row sums from an array of rowwise independent random variables obtained by Sung, Volodin, and Hu [8] to an array of rowwise independent random elements taking values in a real separable Rademacher type p Banach space. An example is presented which illustrates that our result extends the Sung, Volodin, and Hu result even for the random variable case. 相似文献
135.
《随机分析与应用》2013,31(4):731-753
For a sequence of independent random elements {V n ,n≥1} in a real separable Banach space X, necessary and, separately, sufficient conditions are provided for the strong law of large numbers ∑ i=1 n (V i ?c i )/b n →0 almost certainly to hold where {c n ,n≥1} and {b n >0,n≥1} are suitable sequences of centering elements in X and norming constants, respectively. The necessity result extends a real line result of Martikainen[14] to a Banach space setting. The sufficiency result assumes that X is of Rademacher type p (1≤p≤2) and is new even when X is the real line. It is general enough to include as special cases a strong law of Adler, Rosalsky, and Taylor[2] for sums of independent and identically distributed random elements and a strong law of Heyde[9] for sums of independent (real-valued) random variables. Illustrative examples are provided showing that the results are sharp and an example is presented satisfying the hypotheses of the sufficiency result but not those of Heyde's[9] theorem. 相似文献
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137.
Pranabendu Ganguly Juran Chandra Biswas Samir Kumar Lahiri 《Fiber and Integrated Optics》2013,32(6):511-520
Integrated optic directional couplers consisting of curved waveguides are simulated analytically by solving the Riccati equation. The coupling coefficient between the curved waveguides with a parabolically varying gap and the condition of total power transfer between the waveguides are derived. In order to compute the overall coupling coefficient and hence the power distribution along the waveguides for Ti:LiNbO 3 curved waveguide directional couplers, the coupling coefficient for straight waveguide couplers is computed for different gaps using the effective-index-based matrix method (EIMM). Finally, the power distribution in the curved waveguides along the length is computed. The method is mostly analytical except the effective-index method and is computationally simple. 相似文献
138.
Victor M. Kruglov 《随机分析与应用》2013,31(4):674-683
Kolmogorov's weak law of large numbers for i.i.d. random variables is generalized to a larger class distributions and to a wide class of normalizing sequences. The result is extended to maximal sums of negatively associated identically distributed random variables. 相似文献
139.
B. Wierzbowska K. Piotrowski J. Koralewska A. Matynia N. Hutnik K. Wawrzyniecki 《Crystal Research and Technology》2008,43(4):381-389
The experimental results concerning continuous mass crystallization process in L(+)‐ascorbic acid – water system are presented and discussed. Influence of L(+)‐ascorbic acid concentration in a feeding solution and mean residence time of suspension in laboratory DT MSMPR crystallizer on product crystal size distribution as well as nucleation and growth kinetics were determined. Kinetic parameter values were evaluated on the basis of size–independent growth (SIG) kinetic model (McCabe's ΔL law). It was observed, that within the examined range of crystallizer productivity (120–1600 kg LAA crystals m–3h–1) crystal product population of mean size Lm from 0.2 to 0.3 mm and CV from 66.6 to 49% is withdrawn. Linear growth rate values present decreasing trend (from ca. 7 · 10–8 to ca. 6 · 10–8 m s–1) with the productivity increase (assuming constant mean residence time of suspension τ = 900 s). Occurrence of secondary nucleation within the circulated and mixed suspension, resulting from crystal attrition and breakage, was observed. The parameter values in design equation connecting linear growth rate and suspension density with nucleation rate were determined. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
140.