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71.
This paper proves the strong consistence and the central limit theorems for empirical right tail deviations. 相似文献
72.
G. Grätzer and F. Wehrung introduced the lattice tensor product, A?B, of the lattices Aand B. In Part I of this paper, we showed that for any finite lattice A, we can "coordinatize" A?B, that is, represent A?,B as a subset A of B A, and provide an effective criteria to recognize the A-tuples of elements of B that occur in this representation. To show the utility of this coordinatization, we prove, for a finite lattice A and a bounded lattice B, the isomorphism Con A ≌ (Con A)B>, which is a special case of a recent result of G. Grätzer and F. Wehrung and a generalization of a 1981 result of G. Grätzer, H. Lakser, and R.W. Quackenbush. 相似文献
73.
Michel Sebille 《Designs, Codes and Cryptography》2001,22(3):215-219
In 1987, Teirlinckproved that if t and are two integers such that v t(mod(t + 1)!(2t+1) and v t + 1 >0, then there exists a t - (v, t + 1, (t + 1)!(2t+1)) design. We prove that if there exists a (t+1)-(v,k,)design and a t-(v-1,k-2, (k-t-1)/(v-k+1))design with t 2, then there exists a t-(v+1,k, (v-t+1)(v-t)/
(v-k+1)(k-t))design. Using this recursive construction, we prove that forany pair (t,n) of integers (t 2and n 0), there exists a simple non trivial t-(v,k,) design having an automorphism groupisomorphic to n
2. 相似文献
74.
光信息科学与技术专业的建设 总被引:1,自引:0,他引:1
就光信息科学与技术专业建设的专业定位、课程设置、学生毕业后的去向等问题发表了个人的看法。介绍了在这方面的一些做法,提供了有关数据,可供同类专业的建设参考。 相似文献
75.
利用直流电源对发光二极管(LED)的结电容充电,切断直流电源后对LED的电压-时间特性进行测量。当充电电压低于LED复合发光的门槛电压,LED的电压-时间特性与普通二极管的相似。当充电电压高于LED复合发光的门槛电压,首次观察到:开始放电的瞬间会出现一个快速下降过程,快速下降到门槛电压以下;LED上的电压越高,快速下降到的电压越低。对该现象进行分析,得到一些新的结论。当LED的正偏电压高于复合发光的门槛电压后,出现了注入到扩散区的非平衡载流子随正偏电压的提高而减小的现象,即dQ/du<0。 相似文献
76.
Y chromosome kits are successfully applied in cases where human biological material exists. With the development of genotyping ability, more Y chromosomal markers are needed for finer identification of male individuals and lineages. In this study, a developmental validation of a newly emerged Y chromosome kit that combines two different kinds of markers: 38 Y-STRs and 3 Y-indels are conducted. The results show that this kit has high sensitivity when there is a small amount of DNA (125 pg), more than one male (minor:major = 1:7), or a mixture of males and females (male:female = 125pg:1875pg), inhibited substances (800 μM hematin and more than 1600 ng/μL humic acid). The kit exhibits high precision level with a standard deviation of allele size no more than 0.14 nt. Locus DYS481 shows the largest stutter rate, with three stutters per true allele. Population samples are well identified (MP of 0.001106), and mutations can be observed in father–son pairs (46 mutations in 70 pairs, 10 in locus DYS627). Out of all the population samples, 13.2% belong to haplogroup M117-O2a2b1a1, with their ethnic group being Han Chinese. The results show that this kit can improve the performance of identifying male individuals, obtaining more unique haplotypes (increasing from 894 to 918 of 1000 male samples) and higher discrimination capacity (increasing from 0.942 to 0.955) in this study compared to previous widely used Yfiler Plus kit. Besides, it gives information about their paternal lineages in forensic genetic casework and genealogical database construction. 相似文献
77.
宇德明 《数学的实践与认识》2008,38(6):73-79
为了编制和优化施工进度计划,计算构成施工项目的各项工作最早开始时间、最迟开始时间、最早完成时间、最迟完成时间、总时差和自由时差等时间参数十分重要.提出了一种计算工作时间参数新方法.该方法以工作完成时间为决策变量,通过建立和求解线性规划模型来得到各种工作时间参数.其建模思路清晰,不需绘制网络图,能用通用办公软件EXCEL求解.模拟计算表明,用该方法与用标准网络计划技术计算出的工作时间参数完全一致. 相似文献
78.
Self-Affine Sets and Graph-Directed Systems 总被引:1,自引:0,他引:1
Abstract. A self-affine set in R
n
is a compact set T with A(T)= ∪
d∈ D
(T+d) where A is an expanding n× n matrix with integer entries and D
={d
1
, d
2
,···, d
N
} ⊂ Z
n
is an N -digit set. For the case N = | det(A)| the set T has been studied in great detail in the context of self-affine tiles. Our main interest in this paper is to consider the
case N > | det(A)| , but the theorems and proofs apply to all the N . The self-affine sets arise naturally in fractal geometry and, moreover, they are the support of the scaling functions in
wavelet theory. The main difficulty in studying such sets is that the pieces T+d, d∈ D, overlap and it is harder to trace the iteration. For this we construct a new graph-directed system to determine whether
such a set T will have a nonvoid interior, and to use the system to calculate the dimension of T or its boundary (if T
o
≠ ). By using this setup we also show that the Lebesgue measure of such T is a rational number, in contrast to the case where, for a self-affine tile, it is an integer. 相似文献
79.
80.
This article derives from first principles a definition of equivalence for higher‐dimensional Hadamard matrices and thereby a definition of the automorphism group for higher‐dimensional Hadamard matrices. Our procedure is quite general and could be applied to other kinds of designs for which there are no established definitions for equivalence or automorphism. Given a two‐dimensional Hadamard matrix H of order ν, there is a Product Construction which gives an order ν proper n‐dimensional Hadamard matrix P(n)(H). We apply our ideas to the matrices P(n)(H). We prove that there is a constant c > 1 such that any Hadamard matrix H of order ν > 2 gives rise via the Product Construction to cν inequivalent proper three‐dimensional Hadamard matrices of order ν. This corrects an erroneous assertion made in the literature that ”P(n)(H) is equivalent to “P(n)(H′) whenever H is equivalent to H′.” We also show how the automorphism group of P(n)(H) depends on the structure of the automorphism group of H. As an application of the above ideas, we determine the automorphism group of P(n)(Hk) when Hk is a Sylvester Hadamard matrix of order 2k. For ν = 4, we exhibit three distinct families of inequivalent Product Construction matrices P(n)(H) where H is equivalent to H2. These matrices each have large but non‐isomorphic automorphism groups. © 2008 Wiley Periodicals, Inc. J Combin Designs 16: 507–544, 2008 相似文献