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101.
本文引入似然比概念作为一般连续型随机变量相对于乘积幂函数分布的偏差的一种随机性度量 ,运用鞅理论及分析方法 [3 - 4 ] ,得到了一种新形式的强大数定理 ,即关于随机变量几何平均 Gn(ω)=∏ni=1Xi1 /n的强极限定理 .  相似文献   
102.
章熙康 《数学学报》1996,39(2):175-183
本文对高阶奇性常微分方程的非退化边值问题建立了非共轭性存在定理和上、下解型存在定理.  相似文献   
103.
S A Gangal  R N Karekar 《Pramana》1981,17(6):453-459
A survey of previous studies on vacuum deposited metal films shows that in high frequency measurements, explicit reference to the effect of air-exposure is not made. The present work on bismuth films (in-situ and air-exposed) at dc and rf frequencies, carried out mainly to study the air-exposure effect, shows that in-situ dc and rf and exposed rf all show nearly the same resistivity for thick continuous films. But air-exposed dc film resistances, when compared to in-situ dc resistances, show that the grain boundary reflection coefficient, R gin Mayadas-Shatzkes model changes from 0·2 to 0·6. This is shown to be due to the grain boundary oxidation. The result is substantiated by rf measurements.  相似文献   
104.
A differential geometric approach to the constrained function maximization problem is presented. The continuous analogue of the Newton-Raphson method due to Branin for solving a system of nonlinear equations is extended to the case where the system is under-determined. The method is combined with the continuous analogue of the gradient-projection method to obtain a constrained maximization method with enforced constraint restoration. Detailed analysis of the global behavior of both methods is provided. It is shown that the conjugate-gradient algorithm can take advantage of the sparse structure of the problem in the computation of a vector field, which constitutes the main computational task in the methods.This is part of a paper issued as Stanford University, Computer Science Department Report No. STAN-CS-77-643 (Ref. 45), which was presented at the Gatlinburg VII Conference, Asilomar, California, 1977. This work was supported in part by NSF Grant No. NAT BUR OF ECON RES/PO No. 4369 and by Department of Energy Contract No. EY-76-C-02-0016.The main part of this work was presented at the Japan-France Seminar on Functional Analysis and Numerical Analysis, Tokyo, Japan, 1976. The paper was prepared in part while the author was a visitor at the Department of Mathematics, North Carolina State University, Raleigh, North Carolina, 1976–77, and was completed while he was a visitor at the Computer Science Department, Stanford University, Stanford, California, 1977. He acknowledges the hospitality and stimulating environment provided by Professor G. H. Golub, Stanford University, and Professors N. J. Rose and C. D. Meyer, North Carolina State University.  相似文献   
105.
It is demonstrated that horizontai sandwich tank with two cover plates can be used to preconcentrate sample solutions. Narrow sharply-defined starting zones are obtained just outside the smaller cover plate when the series of spots of the sample solution are applied on the thin layer and predeveloped with a volatile solvent. After evaporation of the solvent, the whole area of the TLC-plate is covered with two plates and developed with a suitable solvent.  相似文献   
106.
Let = {Ut: t > 0} be a strongly continuous one-parameter group of operators on a Banach space X and Q be any subset of a set (X) of all probability measures on X. By (Q; ) we denote the class of all limit measures of {Utn1 * μ2*…*μn)*δxn}, where {μn}Q, {xn}X and measures Utnμj (j=1, 2,…, n; N=1, 2,…) form an infinitesimal triangular array. We define classes Lm( ) as follows: L0( )= ( (X); ), Lm( )= (Lm−1( ); ) for m=1, 2,… and L( )=m=0Lm( ). These classes are analogous to those defined earlier by Urbanik on the real line. Probability distributions from Lm( ), m=0, 1, 2,…, ∞, are described in terms of their characteristic functionals and their generalized Poisson exponents and Gaussian covariance operators.  相似文献   
107.
We determined photodynamic therapy (PDT) efficacy using a flash wave (FW) and a continuous wave (CW) light, of which the fluence rate was 70 W/cm2, for murine thymic lymphoma cells (EL-4) cultivated in vitro. The irradiation frequency and the pulse width of the FW light were in the range of 1–32 Hz and less than one millisecond, respectively. 5-Aminolevulinic acid-induced protoporphyrin IX (ALA-PpIX) was used as a photosensitizer. When EL-4 with ALA administration was irradiated by the light for 4 h (irradiation fluence: 1.0J/cm2), the survival rate of EL-4 by the FW light was lower than that by the CW light, except for the FW light with irradiation frequency of 32 Hz, and decreased gradually with decreasing irradiation frequency. Moreover, the FW light, especially at lower irradiation frequency, was superior to the CW light for the generation of singlet oxygen in an aqueous PpIX solution. Therefore, thehigher PDT efficacy for EL-4 of the FW light would be caused by the greater generation of singlet oxygen in the cells.  相似文献   
108.
We present a new example of a potential such that the corresponding Schrödinger operator in the halfaxis has singular continuous spectrum embedded in the absolutely continuous spectrum. The singular part is supported in an essentialy dense set. This generalizes a result of C. Remling [3].Mathematics Subject Classification: 34L40, 81Q10.  相似文献   
109.
We study the existence of vector spaces of dimension at least two of continuous functions on (subsets of) , every non-zero element of which admits one and only one absolute maximum.  相似文献   
110.
Klimkin  V. M.  Sribnaya  T. A. 《Mathematical Notes》2003,74(1-2):56-63
Conditions for the uniform continuity of a family of weakly regular set functions defined on an algebra of subsets of a -topological space (T,) and taking values in an arbitrary topological space are found.  相似文献   
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