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排序方式: 共有355条查询结果,搜索用时 15 毫秒
91.
分块矩阵及矩阵和的秩 总被引:1,自引:0,他引:1
用分块矩阵的广义逆矩阵给出了分块矩阵的秩与子块秩的关系,及三个矩阵和的秩的范围。 相似文献
92.
设A是2n×2n矩阵,根据矩阵的性质,得到了2n×2n矩阵A的k次幂,推广了P.J.Blatz,Kenneth S和Williams的相关结果. 相似文献
93.
称双序集E为双序集F用矩形双序集的余扩张,若存在满双序集态射θ:E→F,使对每个α∈F,αθ-1是E的矩形双序子集.本文讨论了拟正则双序集的这种余扩张的性质,给出了它们的结构.作为应用,证明了拟正则的硬双序集实为正则双序集. 相似文献
94.
G. E. Puninskii 《Mathematical Notes》1999,66(5):608-612
It is proved that the category of modules of finite length over a broad class of generalized Weyl algebras contains no left
almost split morphism starting from a simple module. It is shown that a similar assertion holds for the algebraUsl2(k) over an algebraically closed field k of characteristic 0. As a by-product, a new series of simple modules for such algebras
is constructed.
Translated fromMatematicheskie Zametki, Vol. 66, No. 5 pp. 734–740, November, 1999. 相似文献
95.
Various aspects of the traditional homotopy theory of topological spaces may be developed in an arbitrary 2-category C with zeros. In particular certain secondary composition operations called box brackets recently have been defined for C; these are similar to, but extend, the familiar Toda brackets in the topological case. In this paper we introduce further the notion of a suspension functor in C and explore the ramifications of relativizing the theory in terms of the associated lax morphism category of C, denoted mC. Four operations associated to a 3-box diagram are introduced and relations among them are clarified. The results and insights obtained, while by nature somewhat technical, yield effective and efficient techniques for computing many operations of Toda bracket type. We illustrate by recording some computations from the homotopy groups of spheres. Also the properties of a new operation, the 2-sided matrix Toda bracket, are explored. 相似文献
96.
提出了分组Karhunen-Leove变换(KLT)和整数小波变换(IWT)的高光谱图像数据压缩方法,并采用整数小波变换技术和Set Partitioning in Hierarchical Trees(SPIHT)压缩编码,实现了对分组Karhun-Loeve变换后的数据压缩。该压缩编码方法与现有压缩方法相比,既保留了Karhun-Loeve变换压缩性能和整数小波变换高压缩比的特点,也宜于实时传输。实验结果表明,分组Karhun-Loeve变换/整数小波变换/SPIHT在相同压缩比下,峰值信噪比比Karhun-Loeve变换/小波变换/WSFCVQ、Karhun-Loeve变换/小波变换/改进的对块零树编码压缩和Karhun-Loeve变换/WT/FSVQ分别提高了6 dB,9 dB和8 dB,运算时间减少一半,整体压缩性能有了较大的提高。 相似文献
97.
A Study of the Equivalence of the BLUEs between a Partitioned Singular Linear Model and Its Reduced Singular Linear Models 总被引:6,自引:0,他引:6
Abstract
Consider the partitioned linear regression model
and its four reduced linear models, where y is an n × 1 observable random vector with E(y) = Xβ and dispersion matrix Var(y) = σ2
V, where σ2 is an unknown positive scalar, V is an n × n known symmetric nonnegative definite matrix, X = (X
1 : X
2) is an n×(p+q) known design matrix with rank(X) = r ≤ (p+q), and β = (β′ 1: β′2 )′ with β1 and β2 being p×1 and q×1 vectors of unknown parameters, respectively. In this article the formulae for the differences between the best linear unbiased
estimators of M
2
X
1β1under the model
and its best linear unbiased estimators under the reduced linear models of
are given, where M
2 = I -X
2
X
2
+ . Furthermore, the necessary and sufficient conditions for the equalities between the best linear unbiased estimators of
M
2
X
1β1 under the model
and those under its reduced linear models are established. Lastly, we also study the connections between the model
and its linear transformation model.
*This work is supported by the National Natural Science Foundation of China, Tian Yuan Special Foundation (No. 10226024),
Postdoctoral Foundation of China and Lab. of Math. for Nonlinear Sciences at Fudan University.
This research is supported in part by The International Organizing Committee and The Local Organizing Committee at the University
of Tampere for this Workshop
**The work is supported in part by an NSF grant of China.
Results in this paper were presented by the first author at The Eighth International Workshop on Matrices and Statistics:
Tampere, Finland, August 1999 相似文献
98.
Let A be a locally finite Abelian R-category with Auslander–Reiten sequences and with Auslander–Reiten quiver (A). We give a criterion for Auslander–Reiten components to contain a cone and apply this result to various categories. 相似文献
99.
G. Castellini 《Applied Categorical Structures》2001,9(3):285-302
A notion of connectedness with respect to a closure operator C and a class of monomorphisms N is introduced in an arbitrary category X. It is shown that under appropriate hypotheses, most classical results about topological connectedness can be generalized to this setting. Examples that illustrate this new concept are provided. 相似文献
100.
Taussky定理推广与应用 总被引:3,自引:1,他引:2
本文在Cassini卵形域上推广了Taussky定理。所得结果修正了Brauer定理,作为应用给出不可约双对角占优矩阵非奇异的充要条件,最后把基本结果推广到分块矩阵上。 相似文献