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1 Introduction Ahugeamountofliteratureexistsonthestudyofi dentifyingtracemetalionsbymeansofspectropho tometry[1 3] ,fluorimetry[4 6 ] aswellas polarogra phy[7 9] ,whichhaveactiononlocatingtheendpointoftheindicatingreaction .Howeverbothspectropho tometryandfluorimetryareeasytobeinterferedbycolororprecipitation ,whilepolarographyhasanissueofmercurypollution .Thecatalyzingkineticanalysishasthecharacteristicsofhighsensitivityandspeedi ness.Oscillographicpotentiometryisasimpleintu itionisticanal… 相似文献
994.
蒋尔雄 《上海大学学报(英文版)》2004,8(4):369-377
QL(QR) method is an efficient method to find eigenvalues of a matrix. Especially we use QL(QR) method to find eigenvalues of a symmetric tridiagonal matrix. In this case it only costs O( n^2) flops, to find all eigenvalues. So it is one of the most efficient method for symmetric tridiagonal matrices. Many experts have researched it. Even the method is mature, it still has many problems need to be researched. We put forward five problems here. They are: (1) Convergence and convergence rate; (2) The convergence of diagonal elements; (3) Shift designed to produce the eigenvalues in monotone order; (4) QL algorithm with multi-shift; (5) Error bound. We intoduce our works on these problems, some of them were published and some are new. 相似文献
995.
This paper is intended to study the volume-preserving procrustes problem arising from practical areas. The correspondingsolution should satisfy a matrix equation which is solved by the singular value decomposition method. Some further results are also given to characterize the solution. Using these results, a numerical algorithm is introduced and some numerical results are provided to illustrate the effectiveness of the algorithm. 相似文献
996.
Probability density function (PDF) method is proposed for analysing the structure of the reconstructed attractor in computing the correlation dimensions of RR intervals of ten normal old men. PDF contains important information about the spatial distribution of the phase points in the reconstructed attractor. To the best of our knowledge, it is the first time that the PDF method is put forward for the analysis of the reconstructed attractor structure. Numerical simulations demonstrate that the cardiac systems of healthy old men are about 6 - 6.5 dimensional complex dynamical systems. It is found that PDF is not symmetrically distributed when time delay is small, while PDF satisfies Gaussian distribution when time delay is big enough. A cluster effect mechanism is presented to explain this phenomenon. By studying the shape of PDFs, that the roles played by time delay are more important than embedding dimension in the reconstruction is clearly indicated. Results have demonstrated that the PDF method represents a promising numerical approach for the observation of the reconstructed attractor structure and may provide more information and new diagnostic potential of the analyzed cardiac system. 相似文献
997.
Using an example,it was analytically proved that the dynamical systems constructed on a star coupled network is more easy to be synchronized than that in coupled map lattices(CML).The result shows that the synchronization in small-world networks may be realized more easily. 相似文献
998.
Propagation stability of non-paraxial beam in nonlinear Kerr media is investigated with a linear stability method.Both theoretical analysis and numerical simulation show that modulation instability(MI) gain spectrum has three different distribution features determined by the times of incident power P0 and the non-paraxial parameter a. Furthermore,the corresponding criterion is put forward to distinguish the three different distributions. 相似文献
999.
Mobile agent technology has drawn a tremendous amount of attention from researchers in distributed computing recently as it promises to provied an elegant and efficient way of solving complex distributed problems,as well as offering a new approach to human-computer-interaction.In mobile agent systems,the mobile agent travels autonomously from one computer to another within the agent enabled networks,executes itself in the agent execution environment,collects useful information and makes its own decision on behalf of its owner.This mobility nature of mobile agent demands its unique name in the whole network otherwise it gets lost or conflicts with other mobile agent having same name.This paper proposes a naming scheme which promises a unique name for a mobile agent within that network. 相似文献
1000.
一种新型高功率密度的正弦波永磁电机 总被引:1,自引:0,他引:1
A novel high power-density PMSM (permanent magnetic synchronous motor) with independent magnetic flux path for each phase is proposed in the paper.The complex mathematic model of PMSM is simplified by decoupling of magnetic flux paths between motor phases.In addition,harmonic compoments are lowered through optimum design of EMF (electric motive force) wave.Thus the ripple torque caused by EMF wave distortion is suppressed. 相似文献