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151.
本文首次提出完美置换的概念并研究它的代数性质和构造方法,解决了2n+1为素数时n阶完美置换的存在性.我们还利用完美置换给出了循环空间均衡拉丁方和对称空间均衡拉丁方的构造方法,它们在试验设计中有广泛的应用。 相似文献
152.
The problem of arranging N unit length weights on a line segment of length N, given a target center of gravity on this line segment, is examined under the assumption that the only information we have about the weights is their order, i.e., a
1 a
2 ... a
N
. Lower bounds on worst case performance of algorithms for this problem are developed, and algorithms (permutations) which come close to achieving these bounds are provided.This work was partially supported under Natural Sciences and Engineering Research Council (NSERC) of Canada research grant number OGP0002507. 相似文献
153.
Masanobu Taniguchi Madan L. Puri 《Annals of the Institute of Statistical Mathematics》1995,47(3):581-600
Suppose thatX
n
=(X
1,...X
n) is a collection ofm-dimensional random vectorsX
i forming a stochastic process with a parameter . Let
be the MLE of . We assume that a transformationA(
) of
has thek-thorder Edgeworth expansion (k=2,3). IfA extinguishes the terms in the Edgeworth expansion up tok-th-order (k2), then we say thatA is thek-th-order normalizing transformation. In this paper, we elucidate thek-th-order asymptotics of the normalizing transformations. Some conditions forA to be thek-th-order normalizing transformation will be given. Our results are very general, and can be applied to the i.i.d. case, multivariate analysis and time series analysis. Finally, we also study thek-th-order asymptotics of a modified signed log likelihood ratio in terms of the Edgeworth approximation.Research supported by the Office of Naval Research Contract N00014-91-J-1020. 相似文献
154.
Planar functions were introduced by Dembowski and Ostrom [4] to describe projective planes possessing a collineation group with particular properties. Several classes of planar functions over a finite field are described, including a class whose associated affine planes are not translation planes or dual translation planes. This resolves in the negative a question posed in [4]. These planar functions define at least one such affine plane of order 3e for every e 4 and their projective closures are of Lenz-Barlotti type II. All previously known planes of type II are obtained by derivation or lifting. At least when e is odd, the planes described here cannot be obtained in this manner. 相似文献
155.
Dinh Tuan Pham Joachim Möcks Lothar Sroka 《Annals of the Institute of Statistical Mathematics》1989,41(3):415-427
The paper provides sufficient conditions for the asymptotic normality of statistics of the form a
ijbRiRj, wherea
ijandb
ijare real numbers andR
iis a random permutation. 相似文献
156.
Sara C. Billey William Jockusch Richard P. Stanley 《Journal of Algebraic Combinatorics》1993,2(4):345-374
Schubert polynomials were introduced by Bernstein et al. and Demazure, and were extensively developed by Lascoux, Schützenberger, Macdonald, and others. We give an explicit combinatorial interpretation of the Schubert polynomial
in terms of the reduced decompositions of the permutation w. Using this result, a variation of Schensted's correspondence due to Edelman and Greene allows one to associate in a natural way a certain set
of tableaux with w, each tableau contributing a single term to
. This correspondence leads to many problems and conjectures, whose interrelation is investigated. In Section 2 we consider permutations with no decreasing subsequence of length three (or 321-avoiding permutations). We show for such permutations that
is a flag skew Schur function. In Section 3 we use this result to obtain some interesting properties of the rational function
, where
denotes a skew Schur function.Sara C. Billey: Supported by the National Physical Science Consortium. William Jockusch: Supported by an NSF Graduate Fellowship. Richard P. Stanley: Partially supported by NSF grants DMS-8901834 and DMS-9206374 相似文献
157.
Hélène Barcelo 《Journal of Algebraic Combinatorics》1993,2(1):5-23
We describe a straightening algorithm for the action of S
n on a certain graded ring
. The ring
appears in the work of C. de Concini and C. Procesi [2] and T. Tanisaki [8], and more recently in the work of A. Garsia and C. Procesi [4]. This ring is a graded version of the permutation representation resulting from the action of S
n on the left cosets of a Young subgroup. As a corollary of our straightening algorithm we obtain a combinatorial proof of the fact that the top degree component of
affords the irreducible representation of S
n indexed by . 相似文献
158.
Jean Michel Sellier Kristina G. Kapanova Jacob Leygonie Gaetan Marceau Caron 《International journal of quantum chemistry》2019,119(23):e26017
Recently neural networks have been applied in the context of the signed particle formulation of quantum mechanics to rapidly and reliably compute the Wigner kernel of any provided potential. Important advantages were introduced, such as the reduction of the amount of memory required for the simulation of a quantum system by avoiding the storage of the kernel in a multi-dimensional array, as well as attainment of consistent speedup by the ability to realize the computation only on the cells occupied by signed particles. An inherent limitation was the number of hidden neurons to be equal to the number of cells of the discretized real space. In this work, anew network architecture is presented, decreasing the number of neurons in its hidden layer, thereby reducing the complexity of the network and achieving an additional speedup. The approach is validated on a onedimensional quantum system consisting of a Gaussian wave packet interacting with a potential barrier. 相似文献
159.
In this paper we prove that the generalized permutation graph G(n,k) is upper embeddable if it has at most two odd subcycles,and that the maximum genus of G(n,k) is more than[β(G(n,k))/3]in most cases. 相似文献
160.
关于图的团符号控制数 总被引:2,自引:0,他引:2
引入了图的团符号控制的概念,给出了n阶图G的团符号控制数γks(G)的若干下限,确定了几类特殊图的团符号控制数,并提出了若干未解决的问题和猜想. 相似文献