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1.
从“断块”学说的观点看,“板块”是断块的一种特殊类型,它是被巨大的深切整个岩石圈的断裂带所围限的断块,是最大一级的断块,称做“岩石圈断块”. 板块学说主要是在对海洋的研究与地球物理研究的基础上发展起来的,它提出了一些有价值的新论点.但大多数研究板块的人,对大陆地区的地质情况还缺乏深入研究,不能充分利用本世纪以来在大陆地质构造研究方面所获得的科学结论与思想方法,这就使板块学说的进一步发展受到了阻碍。 本文先对断块学说的历史发展与现阶段理论作一简单介绍,然后应用断块构造的力学分析与历史分析方法,对板块构造研究中出现的一些主要问题谈一些看法.作者认为板块边界的力学机制主要是受基底锯齿状断裂的活动方式控制的,板块内部的应力分布也主要与板块内部次一级强度不同的断块的复杂活动有关。关于板块运动的驱动力,不但应考虑地球内部的热运动,而且应考虑到重力作用和地球作为一个旋转天体所具有的各种动力学行为.  相似文献   

2.
With an eye on applications in quantum mechanics and other areas of science, much work has been done to generalize traditional analytic methods to p-adic systems. In 2002 the first paper on p-adic wavelets was published. Since then p-adic wavelet sets, multiresolution analyses, and wavelet frames have all been introduced. However, so far all constructions have involved dilations by p. This paper presents the first construction of a p-adic wavelet system with a more general matrix dilation, laying the foundation for further work in this direction.  相似文献   

3.
We obtain asymptotic equalities for the least upper bounds of approximations by Zygmund sums in the uniform metric on the classes of continuous 2π-periodic functions whose (ψ, β)-derivatives belong to the set H ω in the case where the sequences ψ that generate the classes tend to zero not faster than a power function.  相似文献   

4.
5.
In this paper theI andII regularn-simplices are introduced. We prove that the sufficient and necessary conditions for existence of anI regularn-simplex in ℝ n are that ifn is even thenn = 4m(m + 1), and ifn is odd thenn = 4m + 1 with thatn + 1 can be expressed as a sum of two integral squares orn = 4m - 1, and that the sufficient and necessary condition for existence of aII regularn-simplex in ℝ n isn = 2m 2 - 1 orn = 4m(m + 1)(m ∈ ℕ). The connection between regularn-simplex in ℝ n and combinational design is given.  相似文献   

6.
金风送爽,丹桂飘香。在这收获的季节里,中国珠算心算协会和世界珠算心算联合会相继在天津召开会员大会,组成新一届理事会和新的领导机构,这标志着我国和世界珠算心算事业将开启崭新的一页!  相似文献   

7.
The minimum number of total independent partition sets of VE of graph G(V,E) is called the total chromatic number of G denoted by χ t (G). If the difference of the numbers of any two total independent partition sets of VE is no more than one, then the minimum number of total independent partition sets of VE is called the equitable total chromatic number of G, denoted by χ et (G). In this paper, we obtain the equitable total chromatic number of the join graph of fan and wheel with the same order. Supported by the National Natural Science Foundation of China (No. 10771091).  相似文献   

8.
The problem on the number of precomplete classes in the functional system P κ τ is considered, elements of P κ τ are deterministic S-functions defined on words of length τ composed from letters of an alphabet of cardinality κ. An asymptotics for the number of S-precomplete classes in P κ τ is obtained for arbitrary fixed κ and τ tending to infinity.  相似文献   

9.
We calculate \({\mathcal{S}^{{\it Diff}}(S^p \times S^q)}\), the smooth structure set of S p × S q , for p, q ≥ 2 and p + q ≥ 5. As a consequence we show that in general \({\mathcal{S}^{Diff}(S^{4j-1}\times S^{4k})}\) cannot admit a group structure such that the smooth surgery exact sequence is a long exact sequence of groups. We also show that the image of the forgetful map \({\mathcal{S}^{Diff}(S^{4j}\times S^{4k}) \rightarrow \mathcal{S}^{Top}(S^{4j}\times S^{4k})}\) is not in general a subgroup of the topological structure set.  相似文献   

10.
Crossing numbers of graphs are in general very difficult to compute. There are several known exact results on the crossing number of the Cartesian products of paths, cycles or stars with small graphs. In this paper we study cr(KmPn), the crossing number of the Cartesian product KmPn. We prove that for m ≥ 3,n ≥ 1 and cr(KmPn)≥ (n − 1)cr(Km+2e) + 2cr(Km+1). For m≤ 5, according to Klešč, Jendrol and Ščerbová, the equality holds. In this paper, we also prove that the equality holds for m = 6, i.e., cr(K6Pn) = 15n + 3. Research supported by NFSC (60373096, 60573022).  相似文献   

11.
We prove that if the function determining a linear functional over the Hardy space is analytic on the disk of radius greater than 1 then the extremal function of this functional is analytic on the same disk.  相似文献   

12.
The prime graph of a finite group was introduced by Gruenberg and Kegel. The degree pattern of a finite group G associated to its prime graph was introduced in [1] and denoted by D(G). The group G is called k-fold OD-characterizable if there exist exactly k non-isomorphic groups H satisfying conditions (1) |G| = |H| and (2) D(G) = D(H). Moreover, a 1-fold OD-characterizable group is simply called an OD-characterizable group. Till now a lot of finite simple groups were shown to be OD-characterizable, and also some finite groups especially the automorphism groups of some finite simple groups were shown not being OD-characterizable but k-fold OD-characterizable for some k > 1. In the present paper, the authors continue this topic and show that the automorphism groups of orthogonal groups O 10+(2) and O 10(2) are OD-characterizable.  相似文献   

13.
This paper is concerned with the study of the set P -1(0), when P varies over all orthogonally additive polynomials on p and L p spaces. We apply our results to obtain characterizations of the weak-polynomial topologies associated to this class of polynomials.  相似文献   

14.
Some extensions of the results of the first author related with the Hilbert spaces A ω,0 2 of functions holomorphic in the half–plane are proved. Some new Hilbert spaces A ω 2 of Dirichlet type are introduced, which are included in the Hardy space H2 over the half–plane. Several results on representations, boundary properties, isometry, interpolation, biorthogonal systems and bases are obtained for the spaces A ω 2 ? H2.  相似文献   

15.
A family of sets is union-free if there are no three distinct sets in the family such that the union of two of the sets is equal to the third set. Kleitman proved that every union-free family has size at most (1+o(1))( n/2 n ). Later, Burosch–Demetrovics–Katona–Kleitman–Sapozhenko asked for the number α(n) of such families, and they proved that \({2^{\left( {\begin{array}{*{20}{c}} n \\ {n/2} \end{array}} \right)}} \leqslant \alpha \left( n \right) \leqslant {2^{2\sqrt 2 \left( {\begin{array}{*{20}{c}} n \\ {n/2} \end{array}} \right)\left( {1 + o\left( 1 \right)} \right)}}\) They conjectured that the constant \(2\sqrt 2 \) can be removed in the exponent of the right-hand side. We prove their conjecture by formulating a new container-type theorem for rooted hypergraphs.  相似文献   

16.
在高中数学新教材“直线与平面”中,明确地给出了一般图形距离的定义:两个图形F1内的任一点与图形F2内任一点间的距离中的最小值,称为图形F1与图形F2的距离.因为新材料引入丁空间向量,而由向量基本定理知,平面内任一向量都可用两个基向量来唯一表示,我们根据教材的这一新特点,发掘出求距离的方法:最值法.  相似文献   

17.
Let p 1, p 2, p 3, p 4 be four pairwise distinct points in the boundary of complex hyperbolic 2-space H 2 and any three points do not lie in the same C-circle. We show that we are always able to group the four points into two classes such that each class contains two points, the two complex lines spanned by each class are ultra-parallel or intersect. As an application, we can simplify the discussion in the paper [7], in which Parker and Platis used the global geometry coordinates to describe the Falbel’s cross-ratio variety of the four pairwise distinct points on the ∂H 2.  相似文献   

18.
19.
Let be the Galois ring of characteristic 23 and rank n and let . We give an explicit construction of Hadamard difference sets in .}Research supported by NSA grant MDA 904-02-1-0080.  相似文献   

20.
Let Γ be a distance-regular graph of diameter d ≥ 3 with c 2 > 1. Let m be an integer with 1 ≤ m ≤ d − 1. We consider the following conditions:
  (SC) m : For any pair of vertices at distance m there exists a strongly closed subgraph of diameter m containing them.
  (BB) m : Let (x, y, z) be a triple of vertices with ∂Γ(x, y) = 1 and ∂Γ(x, z) = ∂Γ(y, z) = m. Then B(x, z) = B(y, z).
  (CA) m : Let (x, y, z) be a triple of vertices with and |C(z, x) ∩ C(z, y)| ≥ 2. Then C(x, z) ∪ A(x, z) = C(y, z) ∪ A(y, z).
In [12] we have shown that the condition (SC) m holds if and only if both of the conditions (BB) i and (CA) i hold for i = 1,...,m. In this paper we show that if a 1 = 0 < a 2 and the condition (BB) i holds for i = 1,...,m, then the condition (CA) i holds for i = 1,...,m. In particular, the condition (SC) m holds. Applying this result we prove that a distance-regular graph with classical parameters (d, b, α, β) such that c 2 > 1 and a 1 = 0 < a 2 satisfies the condition (SC) i for i = 1,...,d − 1. In particular, either (b, α, β) = (− 2, −3, −1 − (−2) d ) or holds.  相似文献   

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