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1.
引入了FS-偏序集和连续L-偏序集概念,探讨了FS-偏序集和连续L-偏序集的性质.主要结果有(1)每一FS-偏序集都是有限上集生成的,因而是Scott紧的;(2)证明了FS-偏序集(连续L-偏序集)的定向完备化是FS-偏序集(连续L-偏序集);(3)一个偏序集是一个FS-Domain当且仅当它为Lawson紧的FS-偏序集;(4)FS-偏序集(连续L-偏序集)去掉部分极大元后还是FS-偏序集(连续L-偏序集).  相似文献   

2.
In this paper the properties of a Liapunov function and its derivatives are combined in obtaining sufficient conditions for the boundedness and global existence of solutions of the system of differential equations

x=f(t,x) (1)

where f: [0,∞)XRn→ Rn is continuous. The following terms are introduced: (i) a scalar function which is mildly unbounded relative to a subset of Rn,(ii) a scalar function which is radially unbounded relative to a set, (iii) a Liapunov function with mildly negative definite derivative in a set, (iv) a Liapunov function with strongly negative definite derivative in a set, and (v) a set which is unbounded-departing with respect to system (1). As a special case the autonomous system of differential equations which corresponds to (1) is considered and the semi-invariance property of the positive limiting set of a solution is used in the results  相似文献   

3.
In this paper, we investigate a fuzzy version of stability for the additive and quadratic type functional equation $$f(x + y) - f(-x- y) - f(x) + f(- x) -4f(y) + f(2y) = 0,$$ in the sense of Mirmostafaee and Moslehian.  相似文献   

4.
一个六点七边图的填充与覆盖   总被引:2,自引:1,他引:1  
$\lambda{K_v}$为$\lambda$重$v$点完全图, $G$ 为有限简单图. $\lambda {K_v}$ 的一个 $G$-设计 ( $G$-填充设计, $G$-覆盖设计), 记为 ($v,G,\lambda$)-$GD$(($v,G,\lambda$)-$PD$, ($v,G,\lambda$)-$CD$), 是指一个序偶($X,\calB$),其中 $X$ 为 ${K_v}$ 的顶点集, $\cal B$ 为 ${K_v}$ 中同构于 $G$的子图的集合, 称为区组集,使得 ${K_v  相似文献   

5.
BCC-AlgebrasandBCK-AlgebrasZhangXiaohong(张小红);WeiZongli(卫宗礼)(HanzhongTeacher'sCollege,723000)(LuoyangTeacher'sCollege,471022)...  相似文献   

6.
in this paper, new characteristic properties of strongly regular rings are' given.Relations between certain generalizations of duo rings are also considered. The followingconditions are shown to be equivalent: (1) R is a strongly regular ring; (2) R is a left SFring such that every product of two independent closed left ideals of R is zero; (3) R is aright SF-ring such that every product of two independent closed left ideals of R is zero; (4)R is a left SF-ring whose every special left annihilator is a quasi-ideal; (5) R is a right SFring whose every special left annihilator is a quasi-ideal; (6) R is a left SF-ring whose everymaximal left ideal is a quasi-ideal; (7) R is a right SF-ring whose every maximal left ideal isa quasi-ideal; (8) R is a left SF-ring such that the set N(R) of all nilpotent elements of R isa quasi-ideal; (9) R is a right SF-ring such that N(R) is a quasi-ideal.  相似文献   

7.
The SOC-monotone function (respectively, SOC-convex function) is a scalar valued function that induces a map to preserve the monotone order (respectively, the convex order), when imposed on the spectral factorization of vectors associated with second-order cones (SOCs) in general Hilbert spaces. In this paper, we provide the sufficient and necessary characterizations for the two classes of functions, and particularly establish that the set of continuous SOC-monotone (respectively, SOC-convex) functions coincides with that of continuous matrix monotone (respectively, matrix convex) functions of order 2.  相似文献   

8.
In this paper the new concept of B-posets is introduced. Some properties of B-posets and FS-posets are examined. Main results are: (1) Posets obtained from B-posets (FS-posets) by eliminating a proper upper subset, adding two or more finitely many incomparable maximal elements, taking vertical sums w.r.t. a maximal element are also B-posets (FS-posets); (2) A poset is a(n) B-domain (FS-domain) iff it is a Lawson compact B-poset (FS-poset); (3) The directed completions of B-posets (FS-posets) are B-domains (FS-domains); (4) The category B-POS (FS-POS) of B-posets (FS-posets) and Scott continuous maps is cartesian closed and has the category B-DOM (FS-DOM) of B-domains (FS-domains) and Scott continuous maps as a full reflective subcategory.  相似文献   

9.
粘合运算对图的控制参数的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
简单图G的粘合运算G_(uv)指的是重合G的两个顶点{u,v}并且去掉重边和环所得到简单图的运算.本文考虑了粘合运算对图的4个控制参数γ(G),Γ(G),β(G),i(G)的影响.刻画了图G_(uv)与图G的控制参数γ(G),Γ(G),γ(G),i(G)之间的关系.及给出γ(G_(uv))=γ(G)-1和β(G_(uv)=β(G)-1的充要条件.  相似文献   

10.
This paper gives the concepts of finite dimensional irreducible operators((FDI) operators)and infinite dimensional irreducible operators((IDI) operators). Discusses the relationships of(FDI)operators,(IDI) operators and strongly irreducible operators((SI) operators) and illustrates some properties of the three classes of operators. Some sufficient conditions for the finite-dimensional irreducibility of operators which have the forms of upper triangular operator matrices are given. This paper proves that every operator with a singleton spectrum is a small compact perturbation of an(FDI) operator on separable Banach spaces and shows that every bounded linear operator T can be approximated by operators in(Σ FDI)(X) with respect to the strong-operator topology and every compact operator K can be approximated by operators in(Σ FDI)(X) with respect to the norm topology on a Banach space X with a Schauder basis, where(ΣFDI)(X) := {T∈B(X) : T=Σki=1Ti, Ti ∈(FDI), k ∈ N}.  相似文献   

11.
一类二阶非线性微分系统有界性与收敛性的充分必要条件   总被引:4,自引:0,他引:4  
周进 《数学学报》2000,43(3):415-420
本文给出了如下一类二阶非线性微分系统 解的有界性的一些新的充分条件,获得了(S’)的所有解有界或收敛到零的充分必要 条件.所获的结果能够应用于Lienard类型方程 它改进与扩展了[1,2]等文献关于同样问题的一些重要结果.  相似文献   

12.
M. Kano  Gyula Y. Katona   《Discrete Mathematics》2002,250(1-3):265-272
Let G be a graph and f : V(G)→{1,3,5,…}. Then a subgraph H of G is called a (1,f)-odd subgraph if degH(x){1,3,…,f(x)} for all xV(H). If f(x)=1 for all xV(G), then a (1,f)-odd subgraph is nothing but a matching. A (1,f)-odd subgraph H of G is said to be maximum if G has no (1,f)-odd subgraph K such that |K|>|H|. We show that (1,f)-odd subgraphs have some properties similar to those of matchings, in particular, we give a formula for the order of a maximum (1,f)-odd subgraph, which is similar to that for the order of a maximum matching.  相似文献   

13.
The effective elastic material properties of short fiber reinforced polypropylen are determined by means of the self-consistent (SC) method and the interaction direct derivative (IDD) method. In order to account for thermoelastic effective material properties, a Hashin-Shtrikman (HS) based two-step homogenization method with variable reference stiffness is used. The influence of the reference stiffness, dependent on a scalar parameter is investigated. Information on the microstructure are derived by computed tomography scans (µCT) and considered within the homogenization schemes. Thermomechanical properties of a long fiber reinforced polymer (LFRP) and a short fiber reinforced polymer (SFRP) are obtained by means of dynamic mechanical analysis (DMA). Simulation results for SFRP are compared to experimental results. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

14.
Let λ be an irreducible character of Sn corresponding to the partition (r,s) of n. Let A be a positive semidefinite Hermitian n × n matrix. Let dλ(A) and per(A) be the immanants corresponding to λ and to the trivial character of Sn, respectively. A proof of the inequality dλ(A)≤λ(id)per(A) is given.  相似文献   

15.
张圣贵 《数学学报》1998,41(1):137-144
设G是有限群,R是有单位元的G-型分次环,S是包含在R的所有齐次元素组成的集合内的乘法封闭子集,S=x∈Gae(gx,x)a∈S,Deg(a)=g∈G{},S==x∈Gae(gx,xh)a∈S,Deg(a)=g∈G,h∈G{},MG(R)表示以G的元作为行列标的|G|阶矩阵环.本文证明了R关于S满足左Ore条件当且仅当R#G关于S满足左Ore条件当且仅当MG(R)关于S=满足左Ore条件,而且,S-1(R#G)≌(S-1R)#G和S=,-1(MG(R))≌MG(S-1R).  相似文献   

16.
Tubular algebras and affine Kac-Moody algebras   总被引:1,自引:0,他引:1  
The purpose of this paper is to construct quotient algebras L(A)1C/I(A) of complex degenerate composition Lie algebras L(A)1C by some ideals, where L(A)1C is defined via Hall algebras of tubular algebras A, and to prove that the quotient algebras L(A)1C/I(A) are isomorphic to the corresponding affine Kac-Moody algebras. Moreover, it is shown that the Lie algebra Lre(A)1C generated by A-modules with a real root coincides with the degenerate composition Lie algebra L(A)1C generated by simple A-modules.  相似文献   

17.
设${\cal F}$为开平面内的区域$D$上的亚纯函数族, ${\cal F}$中任何函数$f(z)\in{\cal F}$, $f$的零点竽数至少为$k+1$.对于$D$内不等于零的解析函数$a(z)$.若$f(z)$与其微分多项式$D(f)$ IM分担$a(z)$,本文不仅得到${\cal F}$在$D$上正规, 而且得到相应于正规函数的结果.  相似文献   

18.
Forecasting compensatory control, which was first proposed by Wu [ASME J. Eng. Ind. 99 (1977) 708], has been successfully employed to improve the accuracy of workpieces in various machining operations. This low-cost approach is based on on-line stochastic modelling and error compensation. The degree of error improvement depends very much on the accuracy of the modelling technique, which can only be performed on-line in a real-time recursive manner. In this study, the effect of the control input (i.e. the cutting force) is considered in the development of the error models, and the formulation of recursive exogenous autoregressive moving average (ARMAX) models becomes necessary. The nonlinear ARMAX or NARMAX model is also used to represent this nonlinear process. ARMAX and NARMAX models of different autoregressive (AR), moving average (MA) and exogenous (X) orders are proposed and their identifications are based on the recursive extended least square (RELS) method and the neural network (NN) method, respectively. An analysis of the computational results has confirmed that the NARMAX model and the NN method are superior to the ARMAX model and the RELS method in forecasting future machining errors, as indicated by its higher combined coefficient of efficiency.  相似文献   

19.
给出了求函数和分的一种表格式算法.对于函数f(x)g(x),如果f(x)为多项式,而g(x)的高阶和分都能算出,那么f(x)g(x)的和分就可以利用这种表格式算法较快速的算出,它对数列求和有一定的益处.  相似文献   

20.
研究了解析函数与Lipschitz条件,得到了如下两个结果:(i)设D是一平面区域,f(z)在D中解析,00,对任意z∈D有|f′(z)|≤md(z,D)k-1,则f∈Lipk(D)且‖f‖k≤cmk,其中c=c(D)是仅与D有关的常数.  相似文献   

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