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171.
杨启帆 《高校应用数学学报(A辑)》1998,13(2):193-196
此文考察工时依赖于开工时间的排序问题.文章证明:(1)即使准奋时间完全相同,判断工时与开工时间相关的单台机排序问题是否有可行解也是NP完全的.(2)即使只存在两个不同的截止期,判断工时与开工时间相关的单台机排序问题是否有可行解仍然是NP完全的.(3)当所有工件有相同截止期时,问题是否有可行解可在多项式时间内判定. 相似文献
172.
For a complete lattice C, we consider the problem of establishing when the complete lattice of complete congruence relations on C is a complete sublattice of the complete lattices of join- or meet-complete congruence relations on C. We first argue that this problem is not trivial, and then we show that it admits an affirmative answer whenever C is continuous for the join case and, dually, co-continuous for the meet case. As a consequence, we prove that if C is continuous then each principal filter generated by a continuous complete congruence on C is pseudocomplemented.
Received January 6, 1998; accepted in final form July 2, 1998. 相似文献
173.
The completeness of solutions of homogeneous as well as non-homogeneous unsteady Stokes equations are examined. A necessary
and sufficient condition for a divergence-free vector to represent the velocity field of a possible unsteady Stokes flow in
the absence of body forces is derived. 相似文献
174.
Jong-Seon No 《Designs, Codes and Cryptography》2004,33(3):199-213
In this paper, for a prime power q, new cyclic difference sets with Singer para- meters ((q
n
–1/q–1), (q
n–1–1/q–1), (q
n–2–1/q–1)) are constructed by using q-ary sequences (d-homogeneous functions) of period q
n
–1 and the generalization of GMW difference sets is proposed by combining the generation methods of d-form sequences and extended sequences. When q is a power of 3, new cyclic difference sets with Singer parameters ((q
n
–1/q–1), (q
n–1–1/q–1), (q
n–2–1/q–1)) are constructed from the ternary sequences of period q
n
–1 with ideal autocorrelation introduced by Helleseth, Kumar, and Martinsen. 相似文献
175.
独立与NA列部分和的精致渐近性 总被引:8,自引:2,他引:6
令{X,Xi:i≥1)为属于非退化稳定分布一般吸引场的独立同分布随机变量列,Sn=∑i=1nXi.本文对十分广泛的拟权函数和边界函数得到了Sn的精致渐近的结果和正态吸引场强平稳NA列部分和的精致渐近的结果,改进并推广了Wang等的结果,从而使此前关于独立列和NA列部分和精致渐近性方面的许多经典的和最新的结果都可以包括在本文的框架之内. 相似文献
176.
In this paper some decompositions of Cauchy polynomials, Ferrers-Jackson polynomials and polynomials of the form x
2n
+ y
2n
, n ∈ ℕ, are studied. These decompositions are used to generate the identities for powers of Fibonacci and Lucas numbers as well
as for powers of the so called conjugate recurrence sequences. Also, some new identities for Chebyshev polynomials of the
first kind are presented here. 相似文献
177.
We continue the study of the linear complexity of binary sequences, independently introduced by Sidel’nikov and Lempel, Cohn,
and Eastman. These investigations were originated by Helleseth and Yang and extended by Kyureghyan and Pott. We determine
the exact linear complexity of several families of these sequences using well-known results on cyclotomic numbers. Moreover,
we prove a general lower bound on the linear complexity profile for all of these sequences. 相似文献
178.
Andreas Rosenschon 《Topology》2005,44(6):1159-1179
We solve the homotopy limit problem for two-primary algebraic K-theory of fields, that is, the Quillen-Lichtenbaum conjecture at the prime 2. 相似文献
179.
本文讨论了完备李代数的同构问题,并对幂零根基为一些Heisenberg代数及交换李代数之直和的可解和一般完备李代数的结构进行了讨论. 相似文献
180.
冯克勤 《高校应用数学学报(A辑)》1992,(3)
In this paper we present a series of binary sequences which is a generalization of GMW sequences constructed by Scholtz and Welch. Our sequences have optimal autocorrelation values as m -sequences, and nice pseudo-random property. The number of such sequences is counted and the linear span of such sequences is evaluated. 相似文献