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1.
Suppose {X, X
n
;n≥1} is a sequence i.i.d.r.v. withEX=0 andEX
2<∞. Shao (1995) proved a conjecture of Révész (1990); ifP(X=±1)=1/2, then
. Furthermore he conjectured that
. In this paper we prove that if
then this conjecture is ture.
Project (10071072) supported by National Natural Science Foundation of China(NSFC). 相似文献
2.
周士藩 《赣南师范学院学报》1987,(Z1)
众所周知,每一非奇异矩阵A有唯一的逆矩阵,通常记为A~(-1),并且,若A~(-1)=B~(-1),则A=B。类似地,设An{i、j、…、k)是已知矩阵A_n的一个广义逆类(n=1、2),并且若A_1{i,j、…、k}=A_2{i、j、…、k}(i、j、…,k∈{1、2、3、4、5})。那么,A_1=A_2吗? 在这篇文章中,我们解决上述这些问题。 相似文献
3.
陈玉成 《鹭江职业大学学报》2014,(5):98-101
研究序列{Xn},{Xn}满足Xn = Yn（mod 2）,其中Yn∈Z＋, Y0≥2, Yn＋1= Yn ＋[Yn/2],证明了{Xn}为一独立随机变量序列,并且是一时间齐次Markov链。最后,利用该Markov链{Xn}的性质,证明了入圈问题经过有限次插点, Cm 的任意一边上都至少插入一个新点。 相似文献
4.
Researchers have speculated that children find it more difficult to acquire conceptual understanding of the inverse relation
between multiplication and division than that between addition and subtraction. We reviewed research on children and adults’
use of shortcut procedures that make use of the inverse relation on two kinds of problems: inversion problems (e.g., 9 ×24 ?24 {9} \times {24} \div {24} ) and associativity problems (e.g., 9 ×24 ?8 {9} \times {24} \div {8} ). Both can be solved more easily if the division of the second and third numbers is performed before the multiplication of
the first and second numbers. The findings we reviewed suggest that understanding and use of the inverse relation between
multiplication and division develops relatively slowly and is difficult for both children and adults to implement in shortcut
procedures if they are not flexible problem solvers. We use the findings to expand an existing model, highlight some similarities
and differences in solvers’ use of conceptual knowledge across operations, and discuss educational implications of the findings. 相似文献
5.
研究从属的双调和映射序列{fn}的收敛性.首先,讨论满足fn〈fn＋1的双调和映射序列{fn}的收敛性,应用{（fn）z（0）}的收敛性给出了从属序列的收敛性的充分和必要条件.其次,证明了满足fn＋1〈fn的双调和映射序列{fn}是收敛的,极限函数是常数当且仅当limn→∞αn=α=0. 相似文献
6.
从数列{（1＋1/n）^b）（n∈N＊）和{（1＋1/n）^n＋1）（n∈N＊）的单调性出发,探讨了数列{（1＋1/n）^n＋1/2）（n∈N＊）的单调性,进而研究了数列{（1＋1/n）^n＋a）（n∈N＊,a∈R为常数）的单调性,并得出一般性的结论。 相似文献
7.
证明了对任意的统计测度μ∈T,令Iμ={A■N∶μ(A)=0},则Banach空间X中的序列{xn}统计收敛于x等价于{xn}理想Iμ收敛于x。再设I任一严格理想,X1=span{χA∶A∈I}l∞,UI={μ∈F,μ(A)=0,A∈I},则UI≌X⊥I,进而XB≌c0。 相似文献
8.
利用格上t-模T,给出了完备B rouwer格上矩阵的T型{1}-广义逆的概念,研究了格矩阵的T型{1}-广义逆存在的等价条件,并给出它们的计算方法。 相似文献
9.
＂一A就B＂是一种特殊的复句,A与B之间有因果、并列和转折三种关系。从认知层面来对这三种类型进行分析,考察在主观推测层面和客观反映层面中人们对于命题的信赖程度。 相似文献
10.
Sagar Chakraborty 《Resonance》2018,23(5):597-600
In this classroom article, we present a geometrical interpretation of a well-known inequality \(\frac{x}{1+x} < {ln}(1+x) < {x}-\frac{x^2}{2(1+x)}\) for x > 0. 相似文献
11.
宗教改革过程中,路德派重视教会音乐,创造出德语众赞歌和康塔塔等新的音乐形式,会众通过同唱参与到音乐和仪式之中.相比于天主教会封闭的拉丁文音乐和仪式,路德派平信徒能够凭借母语,在音乐中感受和表达信仰,民众参与的过程就是教士权力削减的过程. 相似文献
12.
贾冠军 《洛阳师范学院学报》2006,25(5):38-40
本文我们给出了B{1,3}A{1,3}(AB){1,3}和B{1,4}A{1,4}(AB){1,4}的一个等价性条件,并由此得到了(AB)+=B+A+的一个新的充分必要条件. 相似文献
13.
讨论了完全图Kn分解成四个顶点的星和圈的存在性,给出完全图Kn存在{C4,S4}-强制分解以及完全图Kn存在{C4,S4}-分解的充要条件. 相似文献
14.
用不同于已有文献的方法研究了一类高阶中立型微分方程,本文不需要条件f∞t0Q(s)ds=∞,获得了这类方程振动性的几个新的结果. 相似文献
15.
The purpose of this research is to analyze the relationship between individual, institutional and demographic characteristics
on one hand and the research productivity of agriculture faculty members on the other. The statistical population of the research
comprises 280 academic staff in agricultural faculties all over Tehran Province. The data regarding research productivity
and demographic characteristics were extracted from the faculty members’ profiles. Questionnaires were utilized to collect
information concerning individual and institutional variables. The reliably of the questionnaire was calculated to be between
0.74 and 0.97 using the Cronbach’s Alpha. The regression analysis revealed that from among demographic characteristics two
variables, namely, academic rank and age (
\textR\textAD 2 {\text{R}}_{\text{AD}}^{ 2} = 0.265), among individual characteristics, three variables, namely, working habits, creativity as well as autonomy and commitment
(
\textR\textAD 2 {\text{R}}_{\text{AD}}^{ 2} = 0.097), and among institutional characteristics four variables namely, network of communication with colleagues, resources
of facilities, corporate management and clear research objectives (
\textR\textAD 2 {\text{R}}_{\text{AD}}^{ 2} = 0.151) were significant predictors for agricultural faculty members’ research productivity. 相似文献
16.
龙希庆 《宜宾师范高等专科学校学报》2010,(6):26-27,47
在乘积格蕴涵代数中研究乘积格蕴涵代数的理想,乘积格蕴涵代数的各种理想之间的关系,证明了A×B是L1×L2的理想（素理想）当且仅当A,B分别是L1和L2的理想（素理想）,两条Lukasiew icz链Lm和Ln的直积Lm×Ln只有{a1}×Ln和Lm×{b1}两个素理想. 相似文献
17.
蒋岳祥 《浙江大学学报(A卷英文版)》2005,6(7):769-774
The sequences {Zi,n, 1≤i≤n}, n≥1 are multi-nomial distribution among i.i.d. random variables {X1,i, i≥1}, {X2,i, i≥1},..., {Xm,i, i≥1}. The extreme value distribution Gz(x) of this particular triangular array of i.i.d. random variables Z1,n, Z2,n,..., Zn,n is discussed. A new type of not max-stable extreme value distributions which are Frechet mixture, Gumbel mixture and Weibull mixture has been found if Fj,...,Fm belong to the same MDA. Whether mixtures of different types of extreme value distributions exist or not and the more general case are discussed in this paper. We found that GZ(X) does not exist as mixture forms of the different types of extreme value distributions after we investigated all cases. 相似文献
18.
乔宗敏 《重庆大学学报(英文版)》2005,4(2):121-124
1 Introduction 1 Let X as a compact metric space with the metric d and f :X → Xas a continuous map. For every nonnegative integer n , define f ninductively by f n = f ? f n?1, with f 0as the identity map on X . If there is a positive integer n such that f n( x )= x, the point x of X is called the periodic point of f and the least n is called the periodic point of x . A periodic point is called a fixed point. Denote the fixed points set and the periodic points set of f respectively by F ( f… 相似文献
19.
20.
马乐 《山东教育学院学报》2014,(2):131-136
“即使A,也B”分为实言句和假言句两类,本文探讨了这个句式的认知层面.主观推测层面,“即使A,也B”这个让步转折句所反映的认识是0＜P{B/A}≤0.5,此时,实言句和假言句是一致的;客观反映层面,“即使A,也B”所反映的认识是：P{B}=1,P{B/Amin（B）}=1,此层面又分为两种情况,一为实言,P{A}=1;二是假言,P{A}=0或P{A}=0.5.说话人使用“即使A,也B”让步转折句,其目的是为了反映出大脑思维这两种不同认知层面所具有的不一致关系. 相似文献