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991.
M. Van Barel E. Van Camp N. Mastronardi 《Numerical Linear Algebra with Applications》2005,12(10):981-1000
Very recently, an algorithm, which reduces any symmetric matrix into a semiseparable one of semi‐ separability rank 1 by similar orthogonality transformations, has been proposed by Vandebril, Van Barel and Mastronardi. Partial execution of this algorithm computes a semiseparable matrix whose eigenvalues are the Ritz‐values obtained by the Lanczos' process applied to the original matrix. Also a kind of nested subspace iteration is performed at each step. In this paper, we generalize the above results and propose an algorithm to reduce any symmetric matrix into a similar block‐semiseparable one of semiseparability rank k, with k ∈ ?, by orthogonal similarity transformations. Also in this case partial execution of the algorithm computes a block‐semiseparable matrix whose eigenvalues are the Ritz‐values obtained by the block‐Lanczos' process with k starting vectors, applied to the original matrix. Subspace iteration is performed at each step as well. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
992.
Joeri Van der Veken 《Results in Mathematics》2008,51(3-4):339-359
We give a full classification of higher order parallel surfaces in three-dimensional homogeneous spaces with four-dimensional
isometry group, i.e., in the so-called Bianchi–Cartan–Vranceanu family. This gives a positive answer to a conjecture formulated
in [2]. As a partial result, we prove that totally umbilical surfaces only exist if the ambient Bianchi–Cartan–Vranceanu space
is a Riemannian product of a surface of constant Gaussian curvature and the real line, and we give a local parametrization
of all totally umbilical surfaces.
Received: December 20, 2006. Revised: March 15, 2007. 相似文献
993.
994.
995.
Phan Van Tuoc 《Journal of Mathematical Analysis and Applications》2008,343(2):826-834
We consider a strongly coupled nonlinear parabolic system which arises in population dynamics in n-dimensional domains (n?1). We prove the global existence of classical solutions to the system for n<10. 相似文献
996.
Karolien De Wael Sandra Van Vlierberghe Hans Buschop Peter Dubruel Bart Vekemans Etienne Schacht Laszlo Vincze Annemie Adriaens 《Surface and interface analysis : SIA》2009,41(5):389-393
The aim of the present paper is to characterize a cross‐linked horse heart cytochrome c (HHC) film on cysteamine‐modified gold electrodes. The HHC film was deposited using 1‐ethyl‐3‐(3‐dimethylaminopropyl)‐carbodiimide (EDC) as a coupling agent. Attenuated total reflection infrared (ATR‐IR) spectroscopic analyses were performed to characterize the newly formed surface on a qualitative and conformational level. The film thickness was measured using a noncontact optical surface profiler, while quantitative data and information on the heterogeneity of the film were obtained by means of synchrotron radiation X‐ray micro fluorescence (SR micro‐XRF). Results indicate that, in addition to electrochemical studies, spectroscopic analysis methods are essential to gain insight in the effect of immobilization strategies on protein conformations. The latter is of relevance in the development and optimization of biosensors. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
997.
Elke Debie Lize Jaspers Patrick Bultinck Wouter Herrebout Benjamin Van Der Veken 《Chemical physics letters》2008,450(4-6):426-430
It is shown how the presence of a chiral compound in solution induces chirality in the surrounding solvent molecules. Using Vibrational Circular Dichroism on camphor dissolved in deuterated chloroform, it is found that the C–D stretch in the latter indeed becomes VCD active. The experimental results agree with ab initio computed spectra for 1:1 associations between the solvent and solute. 相似文献
998.
999.
M. Caymax M. Houssa G. Pourtois F. Bellenger K. Martens A. Delabie S. Van Elshocht 《Applied Surface Science》2008,254(19):6094-6099
Important progress has been made in the passivation of Ge/gate dielectric interfaces. One important approach is by thermally oxidized GeO2 interface and ALD high-k layers, with an interface state density Dit ∼ 2 × 1011 cm−2 eV−1. Another approach is with an epi-Si/SiO2 interface, resulting in similar Dit. Hysteresis and Vth shift, however, are still not optimal. Extensive material characterization and theoretical insights help us understanding the root cause of these remaining issues and show the way to improved interface control. 相似文献
1000.
To document the details of flow characteristics around modern commercial ships, global force, wave pattern, and local mean
velocity components were measured in the towing tank. Three modern commercial hull models of a container ship (KRISO container
ship = KCS) and of two very large crude-oil carriers (VLCCs) with the same forebody and slightly different afterbody (KVLCC
and KVLCC2) having bow and stern bulbs were selected for the test. Uncertainty analysis was performed for the measured data
using the procedure recommended by the ITTC. Obtained experimental data will provide a good opportunity to explore integrated
flow phenomena around practical hull forms of today. Those can be also used as the validation data for the computational fluid
dynamics (CFD) code of both inviscid and viscous flow calculations.
Received: 26 September 2000/Accepted: 22 May 2001 相似文献