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941.
Two non desarguesian flag transitive planes of order 34 whose Kernel is GF(3) are constructed. These planes are distinct from the planes of the same order contained in the class constructed by Narayana Rao M. L. (Proceedings of American Mathematical Society 39 (1973) 51–56) and Ebert, G.L. and Baker, R. (Enumeration of two dimensional Flag-Transitive planes, Algebras, Groups and Geometries 3 (1985) 248–257). The Flag Transitive group modulo the scalar collineations of these planes is generated by two elements and is of order 328. 相似文献
942.
The issue is that of following the path of a Brownian particle by a process of bounded total variation and subject to a reflecting barrier at the origin, in such a way as to minimize expected total cost over a finite horizon. We establish the existence of optimal processes and the dynamic programming equations for this question, and show (by purely probabilistic arguments) its relation to an appropriatefamily of optimal stopping problems with absorption at the origin.Work carried out during a visit by the second author at the University Pierre et Marie Curie (Paris VI), and at INRIA (Institut National de Recherche en Informatique et en Automatique). The hospitality of these institutions is gratefully acknowledged.Research supported in part by the U.S. Air Force Office of Scientific Research, under grant AFOSR-86-0203. 相似文献
943.
The aim of this paper is to describe a new approach to building minimal and perfect hash functions for a predefined set of keys. Several papers have dealt with this problem and proposed various kinds of functions. This study is based on a function whose address depends both on the letter codes and the letter position in the key, and therefore represents an extension of Cichelli's function. The weights associated with the position are considered to be fixed, and letter code computing is considered to be an interpolation problem. As a result, hash building only requires the solution of an algebraic linear system and then the time complexity is polynomialO(n
3). 相似文献
944.
Ernst S. Selmer 《BIT Numerical Mathematics》1989,29(1):37-40
A boundO(N
1+1/k
) for the running time of Shellsort, withO(logN) passes, is proved very simply by application of a Frobenius basis withk elements. 相似文献
945.
For any listL ofn numbers in (0, 1) letL* denote the minimum number of unit capacity bins needed to pack the elements ofL. We prove that, for every positive ε, there exists anO(n)-time algorithmS such that, ifS(L) denotes the number of bins used byS forL, thenS(L)/L*≦1+ε for anyL providedL* is sufficiently large.
The work of this author was supported by NSF Grant MCS 70-04997. 相似文献
946.
Let FX,Y(x,y) be a bivariate distribution function and Pn(x), Qm(y), n, m = 0, 1, 2,…, the orthonormal polynomials of the two marginal distributions FX(x) and FY(y), respectively. Some necessary conditions are derived for the co-efficients cn, n = 0, 1, 2,…, if the conditional expectation E[Pn(X) ∥ Y] = cnQn(Y) holds for n = 0, 1, 2,…. Several examples are given to show the application of these necessary conditions. 相似文献
947.
Error patterns are lost in the data compression process inherent in signature analysis. These however contain useful information about the faults in faulty units. The present paper investigates the possibility to recover the lost error patterns from the signatures obtained at the end of a test run. It is shown that, the recovery is possible if the test outcome sequence is not longer than the signature analyser period and if the number of possible error signatures can be reduced to a subset a priori known. 相似文献
948.
A. W. Davis 《Annals of the Institute of Statistical Mathematics》1981,33(1):297-313
Summary The construction of a class of invariant polynomials in several matrices extending the zonal polynomials is discussed. The
method adopted generalized the orginal group-theoretic approach of James [9]. A table of three-matrix polynomials up to degree
5 is presented.
CSIRO 相似文献
949.
A. C. Albu 《Periodica Mathematica Hungarica》1977,8(2):151-159
Sans résumé
This article is the text of a talk given at the Symposium on Differential Geometry in Debrecen, Hungary, on August 28–September 3, 1975. 相似文献
950.
Richard A Davis 《Journal of multivariate analysis》1983,13(2):273-286
The aim of this paper is to examine the weak limiting behavior of upper and lower extremes from stationary sequences satisfying dependence conditions similar to D and D′ introduced by Leadbetter (Z. Wahrsch. Verw. Gebiete28 (1974), 289–303). By establishing the convergence in distribution of an associated sequence of point processes, the joint limiting distribution of any collection of upper and lower extremes can be determined. Sufficient and, in some cases, necessary conditions for the asymptotic independence of the upper and lower extremes are also given. 相似文献