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81.
Multivariate Refinement Equations and Convergence of Cascade Algorithms in Lp(0〈p〈1)Spaces 总被引:1,自引:0,他引:1
SongLI 《数学学报(英文版)》2003,19(1):97-106
We consider the solutions of refinement equations written in the form
where the vector of functions ϕ = (ϕ
1, ..., ϕ
r
)
T
is unknown, g is a given vector of compactly supported functions on ℝ
s
, a is a finitely supported sequence of r × r matrices called the refinement mask, and M is an s × s dilation matrix with m = |detM|. Inhomogeneous refinement equations appear in the construction of multiwavelets and the constructions of wavelets on a finite
interval. The cascade algorithm with mask a, g, and dilation M generates a sequence ϕ
n
, n = 1, 2, ..., by the iterative process
from a starting vector of function ϕ
0. We characterize the L
p
-convergence (0 < p < 1) of the cascade algorithm in terms of the p-norm joint spectral radius of a collection of linear operators associated with the refinement mask. We also obtain a smoothness
property of the solutions of the refinement equations associated with the homogeneous refinement equation.
This project is supported by the NSF of China under Grant No. 10071071 相似文献
82.
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提出了一种新型栅耦合型静电泄放(ESD)保护器件——压焊块电容栅耦合型保护管.该结构不仅解决了原有栅耦合型结构对特定ESD冲击不能及时响应的问题,而且节省了版图面积,提高了ESD失效电压.0.5 μm标准互补型金属氧化物半导体工艺流片测试结果表明,该结构人体模型ESD失效电压超过8 kV.给出了栅耦合型ESD保护结构中ESD检测结构的设计方法,能够精确计算检测结构中电容和电阻的取值.
关键词:
静电泄放
栅耦合
金属氧化物半导体场效应管
压焊块电容 相似文献
84.
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New Power Lateral Double Diffused Metal-Oxide-Semiconductor Transistor with a Folded Accumulation Layer 下载免费PDF全文
A new lateral double diffused metal oxide semiconductor field effect transistor with a double-charge accumulation layer using a folded silicon substrate is proposed to improve the performance of the breakdown voltage and specific on-resistance. Three kinds of technologies, which are the additional electric field modulation effect, majority carrier accumulation and increasing the effective conduction area, are applied simultaneously by a semi- insulating polycrystalline silicon layer deposited over the top of thin oxide covering the drift region. It is indicated that by the simulator, the ideal silicon limits of the breakdown voltage and specific on-resistance have been broken due to the complete three-dimensional reduced surface field effect and the doubled majority carrier accumulation layer. 相似文献
86.
In this paper an asymptotic formula of Voronovskaja type for a multivariate extension of the Kantorovich generalized sampling
series is given. Moreover a quantitative version in terms of some moduli of smoothness is established. Finally some particular
examples of kernels are discussed, as the Bochner-Riesz kernel and the multivariate splines. 相似文献
87.
1 INTRUDUCTION During the last few years, there has been much effort paid to the synthesis of new transition-metal oxides that might be active hosts for intercalation reactions. Vanadium and molybdenum in higher oxidation states with higher reacting ability tend to form polynuclear, anionic metal-oxygen clusters with an extraordinary variety of the relevant topology and electronic structures[1~3]. The preparation of the corresponding clusters is of special interest for different aspects … 相似文献
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