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排序方式: 共有179条查询结果,搜索用时 15 毫秒
1.
横向放大率法确定复合光学系统的基点   总被引:2,自引:0,他引:2  
曹国荣 《物理实验》2002,22(3):13-14,20
介绍了应用测量横向放大率确定两薄透镜组成的复合光学系统基点的方法。由于采用线阵光电耦合器件(CCD)测量物经光学系统成像的横向放大率,提高了测量精度。  相似文献   
2.
We extract some properties of Mahlo’s operation and show that some other very natural operations share these properties. The weakly compact sets form a similar hierarchy as the stationary sets. The height of this hierarchy is a large cardinal property connected to saturation properties of the weakly compact ideal.  相似文献   
3.
We construct models for the level by level equivalence between strong compactness and supercompactness in which for κ the least supercompact cardinal and δκ any cardinal which is either a strong cardinal or a measurable limit of strong cardinals, 2δ > δ + and δ is < 2δ supercompact. In these models, the structure of the class of supercompact cardinals can be arbitrary, and the size of the power set of κ can essentially be made as large as desired. This extends and generalizes [5, Theorem 2] and [4, Theorem 4]. We also sketch how our techniques can be used to establish a weak indestructibility result. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
4.
横向放大率法测定光具组的基点   总被引:1,自引:1,他引:0  
刘竹琴 《大学物理》2006,25(8):40-41
介绍了用横向放大率法确定两薄透镜组成的光具组基点的原理和方法,该方法采用线阵光电耦合器件(CCD)测量物经光学系统成像的横向放大率,进一步提高了测量精度.  相似文献   
5.
Fuzzy集的基数   总被引:6,自引:0,他引:6  
关于Fuzzy集的基数,[1]中曾对有限支集的Fuzzy集以及极苛刻条件下的无限Fuzzy集给出过一种定义。但是,正如本文将要指出的那样,该定义是不合理的。本文将从研究Fuzzy映射入手,给出Fuzzy集基数的一般性定义。基于这一定义,不但得到有关基数的大部分结论,而且有其自身的特殊性。  相似文献   
6.
We introduce the Bounded Axiom A Forcing Axiom (BAAFA). It turns out that it is equiconsistent with the existence of a regular ∑2‐correct cardinal and hence also equiconsistent with BPFA. Furthermore we show that, if consistent, it does not imply the Bounded Proper Forcing Axiom (BPFA) (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
7.
Baur  Lynne 《Order》2000,17(1):1-21
Initial chain algebras on pseudotrees generalize the notion of an interval algebra on a linear order. Many relationships which hold between the various cardinal functions on interval algebras also hold for initial chain algebras. In particular, for initial chain algebras on pseudotrees, depth equals tightness, spread equals hereditary Lindelöf degree, irredundance equals the cardinality of the algebra, and incomparability equals hereditary cofinality. For interval algebras, Rubin showed that any subalgebra of regular uncountable cardinality contains either a chain of size or a pairwise incomparable family of size . This result holds for initial chain algebras as well.  相似文献   
8.
Natasha Flyer Many types of radial basis functions (RBFs) are global in termsof having large magnitude across the entire domain. Yet, incontrast, e.g. with expansions in orthogonal polynomials, RBFexpansions exhibit a strong property of locality with regardto their coefficients. That is, changing a single data valuemainly affects the coefficients of the RBFs which are centredin the immediate vicinity of that data location. This localityfeature can be advantageous in the development of fast and well-conditionediterative RBF algorithms. With this motivation, we employ hereboth analytical and numerical techniques to derive the decayrates of the expansion coefficients for cardinal data, in both1D and 2D. Furthermore, we explore how these rates vary in theinteresting high-accuracy limit of increasingly flat RBFs.  相似文献   
9.
研究一类特殊的可重复排列性质,建立了一般情形下求这类排列数的递推公式,导出了一些特殊情形下的具体计算公式.  相似文献   
10.
We consider the space D(X, Y) of densely continuous forms introduced by Hammer and McCoy [5] and investigated also by Holá [6]. We show some additional properties of D(X, Y) and investigate the subspace D*(X) of locally bounded real-valued densely continuous forms equipped with the topology of pointwise convergence τ- p . The largest part of the paper is devoted to the study of various cardinal functions for (D*(X), τ p ), in particular: character, pseudocharacter, weight, density, cellularity, diagonal degree, π-weight, π-character, netweight etc. This work was supported by Science and Technology Assistance Agency under the contract No. APVT-51-006904. The authors would like to thank Ľubica Holá for suggestions and comments.  相似文献   
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