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11.
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In this paper we study the optimization issues of ring networks employing novel parallel multi‐granularity hierarchical optical add‐drop multiplexers (OADMs). In particular, we attempt to minimize the number of control elements for the off‐line case. We present an integer linear programming formulation to obtain the lower bound in optimization, and propose an efficient heuristic algorithm called global bandwidth resource assignment that is suitable for the design of large‐scale OADM networks. 相似文献
13.
讨论了输出终端带不等式约束情形的多输入多输出系统,说明了这些约束可以通过修改输入柔化系数而使其得以满足,在柔化系数的选择范围确定过程中,为了避免矩阵求逆,采用利用已知数据辨识参数的方法来确定柔化系数,从而使得问题简化。降低了计算量且加快了收敛速度。 相似文献
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15.
Pnar iviciolu Mustafa Al 《AEUE-International Journal of Electronics and Communications》2004,58(5):311-318
In this paper a new filter, Triangular Interpolant Based Impulsive Noise Suppression Filter (SF), is proposed to restore images corrupted by fixed valued impulsive noise (IN). The proposed filter comprises two main stages: detection of noise and restoration of corrupted pixels. The SF achieves the restoration of the detected noisy pixels by using one of the Triangular Interpolant techniques and leaves the other pixels unaltered. Simulation results reveal that the proposed filter shows better performance than the highly approved IN suppression filters across a wide noise density ranging from 10% to 90%. The proposed filter also perfectly achieves the robustness anddetail preservation with reduced computational complexity. 相似文献
16.
17.
G. Montero L. Gonzlez E. Flrez M. D. García A. Surez 《Numerical Linear Algebra with Applications》2002,9(3):239-247
Parallel preconditioners are presented for the solution of general linear systems of equations. The computation of these preconditioners is achieved by orthogonal projections related to the Frobenius inner product. So, minM∈??∥AM?I∥ F and matrix M0∈?? corresponding to this minimum (?? being any vectorial subspace of ??n(?)) are explicitly computed using accumulative formulae in order to reduce computational cost when subspace ?? is extended to another one containing it. Every step, the computation is carried out taking advantage of the previous one, what considerably reduces the amount of work. These general results are illustrated with the subspace of matrices M such that AM is symmetric. The main application is developed for the subspace of matrices with a given sparsity pattern which may be constructed iteratively by augmenting the set of non‐zero entries in each column. Finally, the effectiveness of the sparse preconditioners is illustrated with some numerical experiments. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
18.
SPECTRUM-PRESERVING ELEMENTARY OPERATORS ON B(X) 总被引:4,自引:0,他引:4
Hou Jinchuan 《数学年刊B辑(英文版)》1998,19(4):511-516
1.IntroductionLetXbeaninfinitedimensionalcomplexBanachspaceandB(X)theBanachalgebraofallboundedlinearoperatorsonX.ForTEB(X),a(T),asusual,willdenotethespectrumofT.Let4bealinearmapfromB(X)intoitself.4isspectrum-preservingifa(di(T))=a(T)forallTEB(X);4isspectrum-compressingifa(4(T))ga(T)forallTEB(X).Itisclearthatif4isunital(i.e.,ac(I)=I),thenacisspectrum-preserving(spectrum-compressing)ifandonlyif4preservesinvertibilityinbothdirections(preservesinvertibility),i.e.,4(T)isinvertibleifando… 相似文献
19.
The theory of tree-growing (RECPAM approach) is developed for outcome variables which are distributed as the canonical exponential family. The general RECPAM approach (consisting of three steps: recursive partition, pruning and amalgamation), is reviewed. This is seen as constructing a partition with maximal information content about a parameter to be predicted, followed by simplification by the elimination of ‘negligible’ information. The measure of information is defined for an exponential family outcome as a deviance difference, and appropriate modifications of pruning and amalgamation rules are discussed. It is further shown how the proposed approach makes it possible to develop tree-growing for situations usually treated by generalized linear models (GLIM). In particular, Poisson and logistic regression can be tree-structured. Moreover, censored survival data can be treated, as in GLIM, by observing a formal equivalence of the likelihood under random censoring and an appropriate Poisson model. Three examples are given of application to Poisson, binary and censored survival data. 相似文献
20.
Zhong Yin Xiao 《International Journal of Infrared and Millimeter Waves》2006,27(6):847-855
A new compact bandpass filter composed of two coupled linear tapered line resonators (LTLRs) is designed. The two resonators
are arranged in different layers. The filter has two transmission zeros on both sides of the passband. It has small size and
steep response below its passband. It is also shown that this filter has 0.6 dB low insertion loss at the centre frequency
and 10.5% 3dB bandwidth.
This work was supported by the Development Foundation of Shanghai Educational Committee (217608) and Shanghai Leading Academic
Discipline Project (T0102). 相似文献