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101.
The aim of this note is to give a direct proof of the fact that the Steinberg formula holds for the Vaserstein symbol and the universal weak Mennicke symbol. We also give an alternate proof of the fact that the Steinberg formula holds for the Vaserstein symbol.  相似文献   
102.
郑晓斌  彭俊彪  韩绍虎 《发光学报》2005,26(1):99-104,i003
无源驱动对高分子发光显示屏质量要求较高,每个像素都应具有完好的二极管特性。为了在选通像素时,消除D.Braun串扰,无源驱动必须断绝选通像素与非选通像素之间的关联,所以需空闲行列上加以反向偏压。但研究表明,对于整流特性比较低的像素,在行扫描的空闲时间内,使驱动IC的VDD与VEE短路,产生相当大的漏电流并在显示屏的电阻网络上形成异常的压降,从而改变空闲行列上的原有电位。这样也就改变了非选通像素的偏置状态,使之正偏导通发光,形成了新的串扰。其表现为两种亮线:一是列串扰。亮度分布与阳极ITO及金属引线电阻有关;二是行串扰。从实验上讨论此两种串扰的产生原因,并提出减缓串扰的可能性。  相似文献   
103.
概念格是根据二元关系提出的一种概念层次结构,它描述了对象和属性的关系,利用矩阵行秩的层次思想提出了一种基于矩阵行秩的概念格生成算法,并用实例描述了对象和属性之间的概念关系.  相似文献   
104.
For analyzing designed high‐dimensional data, no standard methods are currently available. A method that is becoming more and more popular for analyzing such data is ASCA. The mathematics of ASCA are already described elsewhere but a geometrical interpretation is still lacking. The geometry can help practitioners to understand what ASCA does and the more advanced user can get insight into the properties of the method. This paper shows the geometry of ASCA in both the row‐ and column‐space of the matrices involved. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
105.
High resolution photoelectron spectra from transition metal ions in TiO2, V2O5, VO2, V2O3, MnO, Mn2O3, MnO2, Cr2O3, FeO, CoO, NiO, CuO, Cu2O, FeSrO3, and Cu doped CaTiO3 were re-examined using a constrained curve fitting approach. Effective fits of the multiplet splitting present could be attained for the oxides with unfilled 3d bands if multiple final states were assumed. The type of transitions implied, also suggest the classification of these oxides during core level photoelectron emission as either; Mott–Hubbard (V2O5, VO2, V2O3, Cr2O3, and FeO), intermediate (MnO, Mn2O3, and MnO2) or charge transfer type compounds (FeSrO3, CoO, NiO, CuO and Cu doped CaTiO3). These transitions along with relationships defining the splitting energy with respect to the total spin and binding energy are discussed.  相似文献   
106.
For an array {V nk ,k1,n1} of rowwise independent random elements in a real separable Banach space with almost surely convergent row sums , we provide criteria for S n A n to be stochastically bounded or for the weak law of large numbers to hold where {A n ,n1} is a (nonrandom) sequence in .  相似文献   
107.
108.
Let p,qR such that 1<p<2 and . Define
(∗)  相似文献   
109.
The frontal method is a variant of Gaussian elimination that has been widely used since the mid 1970s. In the innermost loop of the computation the method exploits dense linear algebra kernels, which are straightforward to vectorize and parallelize. This makes the method attractive for modern computer architectures. However, unless the matrix can be ordered so that the front is never very large, frontal methods can require many more floating‐point operations for factorization than other approaches. We are interested in matrices that have a highly asymmetric structure. We use the idea of a row graph of an unsymmetric matrix combined with a variant of Sloan's profile reduction algorithm to reorder the rows. We also look at applying the spectral method to the row graph. Numerical experiments performed on a range of practical problems illustrate that our proposed MSRO and hybrid MSRO row ordering algorithms yield substantial reductions in the front sizes and, when used with a frontal solver, significantly enhance its performance both in terms of the factorization time and storage requirements. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
110.
孙玉香  许勇 《大学数学》2008,24(3):57-61
就非负不可约三对角矩阵,给出了一种求最大特征值的方法,关键是求迭代因子g的新方法,且证明了此迭代因子大于文献[2]中的迭代因子(r+3d)/(r+2d),从而减少了迭代次数,节约了运算时间.  相似文献   
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