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1.
We investigate the relation between distributional chaos and minimal sets, and discuss how to obtain various distributionally scrambled sets by using least and simplest minimal sets. We show: i) an uncountable extremal distributionally scrambled set can appear in a system with just one simple minimal set: a periodic orbit with period 2; ii) an uncountable dense invariant distributionally scrambled set can occur in a system with just two minimal sets: a fixed point and an infinite minimal set; iii) infinitely many minimal sets are necessary to generate a uniform invariant distributionally scrambled set, and an uncountable dense extremal invariant distributionally scrambled set can be constructed by using just countably infinitely many periodic orbits.  相似文献   

2.
We prove that the union of a Riesz set and a Lust-Piquard set is a Riesz set. This gives as corollaries known results of Y. Katznelson, R.E. Dressler-L. Pigno, and D. Li. Moreover, we give an example of a Rosenthal set which is dense in Z for the Bohr topology.  相似文献   

3.
In this paper we present a new combinatorial class enumerated by Catalan numbers. More precisely, we establish a bijection between the set of partitions π1π2?πn of [n] such that πi+1πi≤1 for all i=,1,2…,n−1, and the set of Dyck paths of semilength n. Moreover, we find an explicit formula for the generating function for the number of partitions π1π2?πn of [n] such that either πi+?πi≤1 for all i=1,2,…,n?, or πi+1πim for all i=1,2,…,n−1.  相似文献   

4.
This is Part I of a two-part paper; the purpose of this two-part paper is (a) to develop new concepts and techniques in the theory of infinite-dimensional programming, and (b) to obtain fruitful applications in continuous time programming. Part I deals with the development of continuous time analogues to those concepts which are the cornerstones of finite-dimensional programming theory. Specifically, a constraint qualification analogous to that found in finite-dimensional programming and a continuous time version of Farkas' theorem are developed. The latter result, stated in terms of convex and polar cones, is then employed in conjunction with the newly-developed constraint qualification to establish necessary conditions and a duality theory for a class of nonlinear continuous time programming problems. This approach to duality permits the imposition of assumptions that are less stringent than those needed for duality in previous formulations of the nonlinear problem.  相似文献   

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In the power setP(E) of a setE, the sets of a fixed finite cardinalityk form across-cut, that is, a maximal unordered setC such that ifX, Y E satisfyXY, X someX inC, andY someY inC, thenXZY for someZ inC. ForE=, 1, and 2, it is shown with the aid of the continuum hypothesis thatP(E) has cross-cuts consisting of infinite sets with infinite complements, and somewhat stronger results are proved for and 1.The work reported here has been partially supported by NSERC Grant No. A8054.  相似文献   

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First of all the authors introduce the concepts of random sub-self-similar set and random shift set and then construct the random sub-self-similar set by a random shift set and a collection of statistical contraction operators.  相似文献   

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The properties of attractor, chain recurrent set and limit set of the flow on a compact metric space are studied.  相似文献   

12.
We prove that ifX is a Polish space andF a face ofP(X) with the Baire property, thenF is either a meager or a co-meager subset ofP(X). As a consequence we show that for every abelian Polish groupX and every analytic Haar-null set Λ⊆X, the set of test measuresT(Λ) of Λ is either meager or co-meager. We characterize the non-locally-compact groups as the ones for which there exists a closed Haar-null setFX withT(F) meager, Moreover, we answer negatively a question of J. Mycielski by showing that for every non-locally-compact abelian Polish group and every σ-compact subgroupG ofX there exists aG-invariantF σ subset ofX which is neither prevalent nor Haar-null. Research supported by a grant of EPEAEK program “Pythagoras”.  相似文献   

13.
Up to now, these are five methods of ranking n fuzzy numbers in order, but these methods contain some confusions and occasionally conflict with intuition. This paper introduces the concept of maximizing set and minimizing set to decide the ordering value of each fuzzy number and uses these values to determine the order of the n fuzzy numbers. In addition, we give a method for calculating the ordering value of each fuzzy number with triangular, trapezoidal, and two-sided drum-like shaped membership functions.  相似文献   

14.
与多目标规划问题的G恰当有效解相应,引进了集合的G恰当有效点的概念,并互研究了G恰当有效点集和G恰当有效解集的连通性.利用所得的结果,还获得多目标规划问题的Pareto有效解集是连通的一个新的结论。  相似文献   

15.
The paper presents a method for describing a finite partially ordered set by means of permutations. Such an approach is convenient, in particular, in studying variant orderings of the original set.Translated from Matematicheskie Zametki, Vol. 4, No. 5, pp. 511–518, November, 1968.In conclusion, I should like to thank the reviewer whose notes I used in preparing the final version of this paper. In particular, I owe to him the recursion method of computing m(A).  相似文献   

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A τ-partition of a subset of a given p-set X can be extended in many different ways to a τ-partition of X. The Stirling number of the second kind S(p, τ) can be defined as the number of all τ-partitions of X, and can be regarded as the number of all possible extensions of the τ-partitions of all the τ-subsets of X. In this paper we study the number of extensions for a particular choice of τ-partitions of the m-subsets of X, with 1 ? m ? p.  相似文献   

18.
Self-similar sets(SSS) are the most important class of Fractals and play an important role in the studies in Fractal. In this note, we introduce self-similar-like sets(SSLS) which generalize self-similar sets,we will show some properties of SSLS which distinguish essentially that of SSS, and we will give also some applications of SSLS.  相似文献   

19.
The estimate is obtained for the diameter d(Sn(a)) of the set Sn(a) of midpoints of chords of length ≥a(0n, namely $$d(S_n (a)) \leqslant \left\{ \begin{gathered} 1 - a^2 /2, n = 2, \hfill \\ \sqrt {1 - a^2 /2,} n \geqslant 3, \hfill \\ \end{gathered} \right.$$ and it is shown that the inequality cannot be improved.  相似文献   

20.
This paper considers sign test under ranked set sampling with unequal set sizes (RSSU), and proposes weighted sign tests associated with judgment ranks. The optimal weight vector is shown to be distribution-free, and RSSU is shown to be more efficient than ranked set sampling.  相似文献   

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