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1.
In a topological Riesz space there are two types of bounded subsets: order bounded subsets and topologically bounded subsets. It is natural to ask (1) whether an order bounded subset is topologically bounded and (2) whether a topologically bounded subset is order bounded. A classical result gives a partial answer to (1) by saying that an order bounded subset of a locally solid Riesz space is topologically bounded. This paper attempts to further investigate these two questions. In particular, we show that (i) there exists a non-locally solid topological Riesz space in which every order bounded subset is topologically bounded; (ii) if a topological Riesz space is not locally solid, an order bounded subset need not be topologically bounded; (iii) a topologically bounded subset need not be order bounded even in a locally convex-solid Riesz space. Next, we show that (iv) if a locally solid Riesz space has an order bounded topological neighborhood of zero, then every topologically bounded subset is order bounded; (v) however, a locally convex-solid Riesz space may not possess an order bounded topological neighborhood of zero even if every topologically bounded subset is order bounded; (vi) a pseudometrizable locally solid Riesz space need not have an order bounded topological neighborhood of zero. In addition, we give some results about the relationship between order bounded subsets and positive homogeneous operators.  相似文献   

2.
3.
It is shown that, for any bounded, injective operator C, the class of injective, densely defined operators with dense range and nonempty resolvent that generate bounded holomorphic C-regularized semigroups is closed under inversion, but, for any n ∈ N, the class of injective, densely defined operators with dense range that generate bounded holomorphic n-times integrated semigroups is very far from being closed under inversion: it is shown that, if both A and A-1 generate bounded holomorphic n-times integrated semigroups of sufficiently large angle θ, then they both generate strongly continuous bounded holomorphic semigroups of angle θ.  相似文献   

4.
局部域上的仿交换算子   总被引:1,自引:0,他引:1  
邹进 《数学学报》1997,40(2):296-300
本文的主要结果是:当A(ξ,η)满足A0,A1,A2,A3,A4时,则T_b在L~2(K)中有界的充要条件是b∈BMO(K).并用此结果推出带符号b的分数次积分交换子,奇异积分交换子在L~2(K)中有界的充要条件,和带符号b的乘子交换子在L~2(K)中有界的一个充分条件.  相似文献   

5.
Grätzer asked in 1971 for a characterization of sublattices of Tamari lattices. A natural candidate was coined by McKenzie in 1972 with the notion of a bounded homomorphic image of a free lattice—in short, bounded lattice. Urquhart proved in 1978 that every Tamari lattice is bounded (thus so are its sublattices). Geyer conjectured in 1994 that every finite bounded lattice embeds into some Tamari lattice.  相似文献   

6.
近十年来,非线性系统的反馈镇定问题引起了控制界广泛的兴趣.人们发现,系统的非线性使得反馈镇定问题变得相当复杂.首先,如 H.J.Sussmann 指出的,非线性系统的能控性不能保证系统是反馈可镇定的.于是线性系统的经验无法借鉴,从而寻找可镇定条件成为一个新的课题.其次,对于一般非线性系统的反馈镇定研究还缺乏得  相似文献   

7.
A harmonic function with constant amplitude and random frequency and phase is called bounded noise. In this paper, the effect of bounded noise on the chaotic behavior of the Duffing oscillator under parametric excitation is studied in detail. The random Melnikov process is derived and a mean-square criterion is used to detect the chaotic dynamics in the system. It is found that the threshold of bounded noise amplitude for the onset of chaos in the system increases as the intensity of the noise in frequency increases. The threshold of bounded noise amplitude for the onset of chaos is also determined by the numerical calculation of the largest Lyapunov exponents. The effect of bounded noise on the Poincaré map and power spectra is also investigated. The numerical results qualitatively confirm the conclusion drawn by using the random Melnikov process with mean-square criterion for larger noise intensity.  相似文献   

8.
A geometric condition for the existence of bounded evaluations is given. Using this criterion for sets of finite perimeter, it is shown that P2(wdm2) has analytic bounded point evaluations, when w is of bounded variation with compact support. This theorem is then related to previous work on bounded point evaluations.Partially supported by a grant from the Research Grants Committee of the University of Alabama.  相似文献   

9.
In this paper we give a new approach to the theory of bounded cohomology. The ideas of relative homological algebra, modified so that they are based on a natural seminorm in the bounded cohomology, play a central role in this approach. Moreover, a new proof is given of the vanishing theorem in the bounded cohomology of simply connected spaces, and also an analog of Leray's theorem on coverings in the theory of bounded cohomology.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 143, pp. 69–109, 1985.  相似文献   

10.
This paper studies the singular limit of the non-isentropic Navier-Stokes equations with zero thermal coefficient in a two-dimensional bounded domain as the Mach number goes to zero. A uniform existence result is obtained in a time interval independent of the Mach number, provided that the initial data satisfy the “bounded derivative conditions”, that is, the time derivatives up to order two are bounded initially, and Navier?s slip boundary condition is imposed.  相似文献   

11.
David M. Riley 《代数通讯》2013,41(10):4619-4634
A Lie algebra is said to satisfy the Baer condition provided each of its 1-dimensional subalgebras is a subideal; if the defect is bounded then the Lie algebra is bounded Baer. We first characterise restricted enveloping algebras (of odd characteristic p) that satisfy the bounded Baer condition. Using this characterisation, we are then able to construct a Lie algebra satisfying the bounded Engel condition, in each odd characteristic p, that does not satisfy the Baer condition. Such a bounded Engel Lie algebra must contain a non-nilpotent 1-generated ideal  相似文献   

12.
This paper studies some important properties of the notion generalized exponential dichotomy. A new notion called generalized bounded growth is introduced to describe the characterization of generalized exponential dichotomy. The relations between generalized bounded growth and generalized exponential dichotomy are established.  相似文献   

13.
A bounded curvature path is a continuously differentiable piecewise C2 path with bounded absolute curvature that connects two points in the tangent bundle of a surface. In this note we give necessary and sufficient conditions for two bounded curvature paths, defined in the Euclidean plane, to be in the same connected component while keeping the curvature bounded at every stage of the deformation. Following our work in [3], [2] and [4] this work finishes a program started by Lester Dubins in [6] in 1961.  相似文献   

14.
设K∈C(R+)和B是一个有界线性算子.作者证明如果犃生成一个指数有界的A正则预解算子族,那么BA,AB或A(I+B),(I+B)A也生成一个指数有界的k-正则预解算子族.此外,作者也给出了k正则预解算子族的加法扰动的相应结果.  相似文献   

15.
中心目的是详细廉政论在随机共轭空间理论形成过程中所经历的三个阶段的工作,尤其指出了这三个阶段工作之间的联系及本质差别;给出了强有界、拓扑有界及几乎处处有界随机线性泛函之间的关系;亦指出了在概率赋范空间上线性算子理论研究中目前存在的不足.  相似文献   

16.
对于一类SISO输入时滞已知,状态时滞不确定但有上界的能采用后推设计方法的非线性系统提出一种基于后推设计、自适应模糊控制和滑模控制的控制方案.通过状态变换,把输入时滞系统转化为无输入时滞的系统.用模糊系统来估计系统的未知连续函数,对转化后的新系统设计自适应滑模控制器,使得新系统的状态有界,通过递推证得原系统的状态半全局一致有界.  相似文献   

17.
A proper vertex coloring of a graph is said to be locally identifying if the sets of colors in the closed neighborhood of any two adjacent non-twin vertices are distinct. The lid-chromatic number of a graph is the minimum number of colors used by a locally identifying vertex-coloring. In this paper, we prove that for any graph class of bounded expansion, the lid-chromatic number is bounded. Classes of bounded expansion include minor closed classes of graphs. For these latter classes, we give an alternative proof to show that the lid-chromatic number is bounded. This leads to an explicit upper bound for the lid-chromatic number of planar graphs. This answers in a positive way a question of Esperet et al. [L. Esperet, S. Gravier, M. Montassier, P. Ochem, A. Parreau, Locally identifying coloring of graphs, Electron. J. Combin. 19 (2) (2012)].  相似文献   

18.
Paul A. Cummings 《代数通讯》2013,41(12):5329-5356
Briefly, a feather is a semigroup derivation diagram with the labels on the edges removed. In this paper, we are concerned with possible definitions for the thickness of a feather.

A major open problem is whether the word problem is solvable for semigroup presentations with one defining relation. It is known that word problems for semigroup presentations are solvable if the number of regions in minimal derivation diagrams is bounded. For some definitions for thickness, the number of regions in a derivation diagram over a presentation with one relation will be bounded if the thickness of the diagram is bounded.  相似文献   

19.
A nonlinear dynamical system which describe the time evolution of n-competitors in a Cournot game (Bowley's model) with bounded rationality is analyzed. The existence and stability of the equilibria of this system is studied. The stability conditions of the steady states for two and three players are explicitly computed. Complex behavior such as cycles and chaotic behavior are observed by numerical simulation. Delayed Bowley's with bounded rationality in monopoly is studied. We show that firms using bounded rationality with delay has a higher chance of reaching Nash equilibrium.  相似文献   

20.
A game with precedence constraints is a TU game with restricted cooperation, where the set of feasible coalitions is a distributive lattice, hence generated by a partial order on the set of players. Its core may be unbounded, and the bounded core, which is the union of all bounded faces of the core, proves to be a useful solution concept in the framework of games with precedence constraints. Replacing the inequalities that define the core by equations for a collection of coalitions results in a face of the core. A collection of coalitions is called normal if its resulting face is bounded. The bounded core is the union of all faces corresponding to minimal normal collections. We show that two faces corresponding to distinct normal collections may be distinct. Moreover, we prove that for superadditive games and convex games only intersecting and nested minimal collection, respectively, are necessary. Finally, it is shown that the faces corresponding to pairwise distinct nested normal collections may be pairwise distinct, and we provide a means to generate all such collections.  相似文献   

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