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991.
Electron pair distribution functions are analyzed for a variety of SCF+CI wavefunctions, for a range of simple molecules. The statistical correlation between electrons of like spin introduced by the antisymmetry requirement on the many-electron wavefunction is contrasted with the manner in which unlike-spin electron correlation is introduced through the inclusion of configuration interaction. 相似文献
992.
Peter Hall 《Stochastic Processes and their Applications》1978,7(3):265-275
Series expansions of moments of order statistics are obtained from expansions of the inverse of the distribution function. They are valid for certain types of distributions with regularly varying tails. We show that the expansions converge quickly when the sample size is moderate to large, and we obtain bounds on the rate of convergence. The special case of the Cauchy distribution is treated in more detail. 相似文献
993.
In the last paper, the geometry of the Sz.-Nagy-Foia
model for contraction operators on Hilbert spaces was used to advantage in several problems of multivariate analysis. The lifting of intertwining operators, one of the basic results from the Sz.-Nagy-Foia
theory, is now recognized as the most adequate operatorial form of the deep classical results of the extrapolation theory. The labeling of the exact intertwining dilations given by [1]Acta Sci. Math. (Szeged) 40 9–32] and the recursive methods used there open a broad perspective for using the Sz.-Nagy-Foia
model in multivariate filtering theory. In this paper, using the notion of correlated action (see [5 and 6] Rev. Roumaine Math. Pures Appl. 23, No. 9 1393–1423]) as a time domain, a linear filtering problem is formulated and its solution in terms of the coefficients of the analytic function which factorizes the spectral distribution of the known data and the coefficients of an analytic function which describes the cross correlations is given. In some special cases it is shown that the filter coefficients can be determined using recursive methods from the intertwining dilation theory, of the autocorrelation function of the known data and an intertwining operator, interpreted as the initial estimator given by the prior statistics. 相似文献
994.
Twenty high energy nuclear interactions produced in the graphite units of an emulsion chamber were recorded. The emulsion
chamber was exposed to cosmic rays at an atmospheric depth of 10 g cm−2 for about 7 hr over Hyderabad, India. Fourteen interactions which radiated energyΣ E
r⩾1000 GeV in the form ofγ-rays were analysed in detail. The median energy 〈Σ E
r〉 of the interactions was 1600 GeV. Results concerning the multiplicity, the transverse and longitudinal momentum distributions,
and the fractional energy distribution ofγ-rays in these interactions are presented. The average transverse momentum ofπ
0—mesons <pt
π
0> is found to increase very slowly with the primary energyE
0 and it can be approximated by the function <pt
π
0>=0·238E
0
0.06
. 相似文献
995.
Hans U. Gerber 《Insurance: Mathematics and Economics》1982,1(1):13-18
The paper develops a method for the numerical evaluation of the distribution of aggregate claims and its stop-loss premiums. 相似文献
996.
Nazakat Ullah 《Pramana》1983,20(2):131-135
An integral which occurs in the new matrix ensembles and the width fluctuation factor is evaluated using a transformation
which changes a Gaussian into an exponential. It is expressed in the form of a series whose terms are found using a simple
recursion relation. It is shown that the series can be summed in closed form for the two-dimensional case. 相似文献
997.
It is proposed in this paper to use the generalized cell mapping to locate strange attractors of dynamical systems and to determine their statistical properties. The cell-to-cell mapping method is based upon the idea of replacing the state space continuum by a large collection of state space cells and of expressing the evolution of the dynamical system in terms of a cell-to-cell mapping. This leads to a Markov chain which in turn allows us to compute all the statistical properties as well as the invariant distribution. After a general discussion, the method is applied in this paper to strange attractors of a variety of systems governed either by point mappings or by differential equations. The results indicate that it is a viable, effective and attractive method. Some comments on this method in comparison with the method of direct iteration will also be made. 相似文献
998.
Fiorella Sgallari 《Applied Mathematical Modelling》1985,9(4):295-301
A weak formulation for ‘direct’ boundary methods for time dependent parabolic problems, deduced from distribution theory, is presented. The present approach seems particularly valuable when dealing with problems with non-integrable singularities and solutions with an exponential growth. Numerical examples are also reported for plane diffusion. 相似文献
999.
Anders Rygh Swensen 《Stochastic Processes and their Applications》1983,15(2):181-191
In this note some problems of asymptotic inference in a class of non-stationary stochastic processes are considered. In particular, it is shown that no criterion based on the existence of uniformly most powerful tests over a local neighborhood can be used in this situation. 相似文献
1000.
Epaminondas Sidiropoulos Christos Tzimopoulos Panagiotis Tolikas 《Applied Mathematical Modelling》1983,7(5):306-310
An indirect boundary element method using dipole distribution is employed in order to model discontinuities inside the flow region. The problem of flow under a dam is treated with a sheet-pile in its foundation. The discontinuity across the sheet-pile is demonstrated, a general boundary element procedure for a mixed problem is outlined and the coefficients of the linear system are given in analytical form. Very good agreement with existing analytical results is obtained. 相似文献