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1.
Green's Equivalences on Semigroups of Transformations Preserving Order and an Equivalence Relation 总被引:4,自引:0,他引:4
Let ${\cal T}_X$ be the full transformation semigroup on the set $X$,
\[
T_{E}(X)=\{f\in {\cal T}_X\colon \ \forall(a,b)\in E,(f(a),f(b))\in E\}
\]
be the subsemigroup of ${\cal T}_X$ determined by an equivalence
$E$ on $X$. In this paper the set $X$ under consideration is a
totally ordered set with $mn$ points where $m\geq 2$ and $n\geq
3$. The equivalence $E$ has $m$ classes each of which contains $n$
consecutive points. The set of all order preserving
transformations in $T_{E}(X)$ forms a subsemigroup of $T_E(X)$
denoted by
\[
{\cal O}_{E}(X)=\{f\in T_{E}(X)\colon \ \forall\, x, y\in X, \ x\leq
y \mbox{ implies } f(x)\leq f(y)\}.
\]
The nature of regular elements in ${\cal O}_{E}(X)$ is described
and the Green's equivalences on ${\cal O}_{E}(X)$ are
characterized completely. 相似文献
2.
N. G. Marchuk 《Proceedings of the Steklov Institute of Mathematics》2014,285(1):197-210
In a pseudo-Euclidean space, a field equation (system of equations) is considered that is invariant under orthogonal (from the group O(p, q)) coordinate transformations and invariant under gauge transformations from the spinor group Pin(p, q). The solutions to the field equation are connected with a class of new particular solutions to the Yang-Mills equations. 相似文献
3.
刘宗光 《数学物理学报(B辑英文版)》2000,20(4)
1 IntroductionLgt b E BMO(Rn) and 11 be a fractional integration with 0 < I < n. The commutator[b, II] generated by b and 11 is defined by[b, II]f(x) = b(x)llf(x) ~ II(sf)(x).S.Chanillolz] stated that the operator [b, II] is a bounded operator from LPI (R") on LPZ(R")for 1/Pz = 1/pl -- l/n and 1 < pl < n/l. Recently, Lu Shanzhen and Yang Dachun[9] studiedthe commutator [b,ll] on Herz spaces and a new class of Herz-type Hardy spaces introducedby them and established the correspondi… 相似文献
4.
磁流体方程组弱解在负指标Besov空间中基于旋度和电流的正则性标准 总被引:1,自引:0,他引:1
本文研究了不可压磁流体方程组弱解的正则性准则,设(u(t,x),6(t,x))是不可压磁流体方程组在(O,T)上的光滑解,如果旋度和电流密度满足(▽× u,▽× b) ∈ L 2-a/2 (O, T;B-aa∞, ∞(R3)) ηL1-a/2(O,T;B-∞1,-a∞(R3)),0<α<1,则光滑解(u(t,x),b(t,x))可以连续延拓到(O,T'),T'>T.而且这个条件可以保证满足能量不等式的弱解是(O,T)上的光滑解. 相似文献
5.
Xu Shusheng 《分析论及其应用》1989,5(1):33-45
We denote En(f) and E
k
n
(f) the best uniform approximations to a continuous function f defined on [a,b] by the sets of algebraic polynomials of degree
≤n and algebraic polynomials of degree ≤n with the coefficients of xk (k≤n) being zero. In this paper, in cases of r<k and r≥k while [a, b]=[−1,1] (or r<k,k≤r<2k and r>2k while [a,b]=[0, 1]),
we separately discuss the condtions for r-times continuously differentiable function f which enables
. 相似文献
6.
7.
8.
徐新萍 《数学的实践与认识》2009,39(10)
设G是一个图,G的部分平方图G*满足V(G*)=V(G),E(G*)=E(G)∪{uv:uv■E(G),且J(u,v)≠■},这里J(u,v)={w∈N(u)∩N(v):N(w)■N[u]∪N[v]}.利用插点方法,证明了如下结果:设G是k-连通图(k2),b是整数,0min {k,(2b-1+k)/2}(n(Y)-1),则G是哈密尔顿图.同时给出图是1-哈密尔顿的和哈密尔顿连通的相关结果. 相似文献
9.
Banach空间中的平均非扩张映象:不动点的存在定理 总被引:7,自引:0,他引:7
<正> 设X是Banach空间,E是X中的集合,T是映集合E到自身的映象.若T满足条件(称为平均非扩张条件)其中x,y∈E,a,b,c≥0且a+2b+2c≤1,则称T是平均非扩张映象. 文[1]概括了近年来研究关于平均非扩张映象不动点的一些主要结果.本文进 相似文献
10.
本文研究Banach空间E中非线性奇异边值问题-x'=f(t,x), t∈(0,1), a1x(0)-a2x'(0)=θ, b1x(0)-b2x'(1)=θ.其中θ是E中的零元素, f({t,x})在端点t=0和t=1处具有奇性. 利用不动点定理获得了该问题至少有两个正解的结果. 相似文献
11.
设$1\leq a<b, 0\leq k$是整数. 设$G$是一个含有$k$-因子$Q$且阶为$|G|$的图. 设\delta(G)$表示$G$的最小度, 且$\delta(G)\geq a+k$. 如果$Q$连通, 设$\varepsilon=k$, 否则设$\varepsilon=k+1$.证明:当$b\geq a+\varepsilon-1$时, 如果对$G$的任意两个不相邻的点$x$和$y$都有max$\{d_G(x),d_G(y)\}\geq {\rm max}\{{{a|G|} \over {a+b}},{{(|G|+(a-1)(2a+b+\varepsilon-2))} \over {b+1}}\}+k$, 那么$G$有一个$[a, b]$-因子$F$ 使得 $E(F)\cap E(Q)=\emptyset$. 这个度条件是最佳的, 条件$b\geqa+\varepsilon-1$不能去掉. 进一步,得到图存在含给定$k$-因子的$[a, b]$-因子的度条件. 相似文献
12.
We define a partial order on the set No,c of pairs (O,C), where O is a nilpotent orbit and C is a conjugacy class in A(O), Lusztig’s canonical quotient of A(O). We
then show that there is a unique order-reversing duality map No,c → LNo,c that has certain properties analogous to those of the original Lusztig–Spaltenstein duality map. This generalizes work of
E. Sommers. 相似文献
13.
P.L. Butzer 《Journal of Fourier Analysis and Applications》1994,1(2):113-130
This paper is devoted to a study of the Hausdorff-Young theorems from a historical perspective, beginning with the F. Riesz-Fischer
theorem. Introduced by W. H. Young (1912), these theorems were considered and extended by F. Hausdorff (1923), F. Riesz (1923),
E.C. Titchmarsh (1924), G. H. Hardy and J.E. Littlewood (1926), M. Riesz (1927), and O. Thorin (1939/48). Special emphasis
is placed upon the development of the proofs of the two Hausdorff-Young inequalities and their impact upon Fourier analysis
as a whole, in particular on the M. Riesz-Thorin convexity theoremand on the interpolation of operators. The golden thread
connecting the various extensions and generalizations is the concept of logarithmic convexity, one that goes back to the work
of J. Hadamard (1896), A. Liapounoff (1901), J.L.W.V. Jensen (1906), and O. Blumenthal (1907). 相似文献
14.
A graph G is called a fractional [a, b]-covered graph if for each e ∈ E(G), G contains a fractional[a, b]-factor covering e. A graph G is called a fractional(a, b, k)-critical covered graph if for any W ? V(G) with|W| = k, G-W is fractional [a, b]-covered, which was first defined and investigated by Zhou, Xu and Sun [S.Zhou, Y. Xu, Z. Sun, Degree conditions for fractional(a, b, k)-critical covered graphs, Information Processing Letters 152(2019)105838]. In this work, we proceed to study fraction... 相似文献
15.
<正> 其中x(·)∈R_n,u(·)∈R_r,A,B分别为n×n,n×r阶复常数阵,R_n,R_r分别为n,r维酉空间,有如下熟知结果:任给n个复数λ_1,…,λ_n,恒存在r×n阶复数阵C,使阵的谱集σ(A+BC)={λ_1,…,λ_n}的充要条件为 相似文献
16.
设E是一个A rch im edean R iesz空间,a∈E,Φ≠A E,则有如下的两个结论:1)由a生成的a-拓扑空间E是一个H ausdorff空间;2)若以下条件之一成立,则由A生成的A-拓扑空间E是一个H ausdorff空间:(a)子集{a:a∈A}有上界;(b)E具有强单位元;(c)若E=C(X),其中X是一个局部紧H ausdorff空间. 相似文献
17.
18.
Krzysztof Piejko Janusz Sokó? 《Journal of Mathematical Analysis and Applications》2008,337(2):1261-1266
We consider a multiplier transformation and some subclasses of the class of meromorphic functions which was defined by means of the Hadamard product by N.E. Cho, O.S. Kwon and H.M. Srivastava in [N.E. Cho, O.S. Kwon, H.M. Srivastava, Inclusion and argument properties for certain subclasses of meromorphic functions associated with a family of multiplier transformations, J. Math. Anal. Appl. 300 (2004) 505-520]. 相似文献
19.
利用 Tchebycheff积分不等式和积分形式的 Cauchy中值定理证明了下列结论 :设 f(x)是 [a,b]上的正连续函数 ,且在 (a,b)内可微 ,若 f′(x)单调递增 ,则对任意的 p,q,有 Mp,q(f) 相似文献
20.
本文研究了连续时间下非参数回归的误差官度估计的收敛速度,给出了一定条件下误差密度的估计量^fT(x)的均方收敛速度,详细说明了以下重要结果:E[^fT(x)-f(x)]^2=O(T^-1/4)其中f(x)表示误差过程{et,t≥0}的未知密度。 相似文献