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161.
Inversion of a triangular matrix can be accomplished in severalways. The standard methods are characterized by the loop ordering,whether matrix-vector multiplication, solution of a triangularsystem, or a rank-1 update is done inside the outer loop, andwhether the method is blocked or unblocked. The numerical stabilityproperties of these methods are investigated. It is shown thatunblocked methods satisfy pleasing bounds on the left or rightresidual. However, for one of the block methods it is necessaryto convert a matrix multiplication into the solution of a multipleright-hand side triangular system in order to have an acceptableresidual bound. The inversion of a full matrix given a factorizationPA=LU is also considered, including the special cases of symmetricindefinite and symmetric positive definite matrices. Three popularmethods are shown to possess satisfactory residual bounds, subjectto a certain requirement on the implementation, and an attractivenew method is described. This work was motivated by the questionof what inversion methods should be used in LAPACK. 相似文献
162.
常全明 《河北理工学院学报》1994,(1)
论述了冀东金矿集中区绿岩型金矿的矿质来源,并恢复其矿源层的原岩。对构造及中小型岩浆任入体的控矿作用作了论述,并提出了成矿模式。 相似文献
163.
This paper gives sensitivity analyses by two approaches forL andU in the factorizationA=LU for general perturbations inA which are sufficiently small in norm. By the matrix-vector equation approach, we derive the condition numbers for theL andU factors. By the matrix equation approach we derive corresponding condition estimates. We show how partial pivoting and complete
pivoting affect the sensitivity of the LU factorization.
The material presented here is a part of the first author's PhD thesis under the supervision of the second author. This research
was supported by NSERC of Canada Grant OGP0009236. 相似文献
164.
Summary Some stability and convergence theorems of the modified Ishikawa iterative sequences with errors for asymptotically nonexpansive
mapping in the intermediate sense and asymptotically pseudo contractive and uniformly Lipschitzian mappings in Banach spaces
are obtained. 相似文献
165.
166.
167.
设计并制作了一种新型长光程薄层光谱电化学池,其具有光程长、灵敏度高、重现性好等特点,且组装简便,电极容易更换,溶液未补偿电阻小,溶液用量少.易清洗.电解池以石墨为工作电极,分别用循环伏安、交流阻抗技术、光谱恒电位技术对其性能进行测试,得到比较满意的结果. 相似文献
168.
Perfect information two-person zero-sum markov games with imprecise transition probabilities 总被引:1,自引:0,他引:1
Hyeong Soo Chang 《Mathematical Methods of Operations Research》2006,64(2):335-351
Based on an extension of the controlled Markov set-chain model by Kurano et al. (in J Appl Prob 35:293–302, 1998) into competitive two-player game setting, we provide a model of perfect information two-person zero-sum Markov games with imprecise transition probabilities. We define an equilibrium value for the games formulated with the model in terms of a partial order and then establish the existence of an equilibrium policy pair that achieves the equilibrium value. We further analyze finite-approximation error bounds obtained from a value iteration-type algorithm and discuss some applications of the model. 相似文献
169.
Let R be a ring. R is called right AP-injective if, for any a ∈ R, there exists a left ideal of R such that lr(a) = Ra (?) Xa. We extend this notion to modules. A right .R-module M with 5 = End(MR) is called quasi AP-injective if, for any s ∈ S, there exists a left ideal Xs of S such that ls(Ker(s)) = Ss (?) Xs. In this paper, we give some characterizations and properties of quasi AP-injective modules which generalize results of Page and Zhou. 相似文献
170.
Design and Fabrication of 1.06 μm Resonant-Cavity Enhanced Reflective Modulator with GaInAs/GaAs Quantum Wells 下载免费PDF全文
A resonant-cavity enhanced reflective optical modulator is designed and fabricated, with three groups of three highly strained InGaAs/GaAs quantum wells in the cavity, for low voltage and high contrast ratio operation. The quantum wells are positioned in antinodes of the optical standing wave. The modulator is grown in a single growth step in an molecular beam epitaxy system, using GaAs/AlAs distributed Bragg reflectors as both the top and bottom mirrors. Results show that the reflection device has a modulation extinction of 3 dB at -4.5 V bias. 相似文献