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1.
Mobile Networks and Applications - Aiming at the problems of large data volume, long calculation time, and information feedback speed in traditional virtual augmented reality-based scenes, this...  相似文献   
2.
Local and Parallel Finite Element Algorithms for Eigenvalue Problems   总被引:4,自引:0,他引:4  
Abstract Some new local and parallel finite element algorithms are proposed and analyzed in this paper foreigenvalue problems.With these algorithms, the solution of an eigenvalue problem on a fine grid is reduced tothe solution of an eigenvalue problem on a relatively coarse grid together with solutions of some linear algebraicsystems on fine grid by using some local and parallel procedure.A theoretical tool for analyzing these algorithmsis some local error estimate that is also obtained in this paper for finite element approximations of eigenvectorson general shape-regular grids.  相似文献   
3.
In this paper, a unified approach for analysing finite dimensional approximations to a class of partial differential equations boundary value problems (second‐kind Fredholm differential equations) is introduced. The approach is shown to be general despite of its extremely simple form. In particular, it is expected to be useful in the convergence analysis of finite element methods for solving PDE problems. Three specific examples are presented to illustrate the broad applicability of the approach. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
4.
In this communication, we report a successful synthesis of quasi-monodisperse In2O3 nanocrystals with high crystallinity in a high-temperature organic solution. The average size of nanocrystals can be tuned using a dynamic injection technique. TEM and XRD investigations indicate that each nanocrystal is a single crystal. The optical determination implies that the photoluminescence behavior of these In2O3 nanocrystals is different from that of the bulk, probably due to the combination of weak quantum-confinement-effects and the nature of high crystallinity in nanocrystals.  相似文献   
5.
We present an algorithm for numerically computing an absolutely continuous invariant measure associated with a piecewiseC 2 expanding mappingS: on a bounded region R N. The method is based on the Galerkin projection principle for solving an operator equation in a Banach space. With the help of the modern notion of functions of bounded variation in multidimension, we prove the convergence of the algorithm.  相似文献   
6.
Some two-scale finite element discretizations are introduced for a class of linear partialdifferential equations. Both boundary value and eigenvalue problems are studied. Basedon the two-scale error resolution techniques, several two-scale finite element algorithmsare proposed and analyzed. It is shown that this type of two-scale algorithms not onlysignificantly reduces the number of degrees of freedom but also produces very accurateapproximations.  相似文献   
7.
In pH 1.99 sodium acetate-HCl buffer solutions at 60 °C, Rhodamine B exhibited a strong fluorescence peak at 584 nm using an excitation wavelength of 548 nm. The fluorescence quenching occurred when Fe3O4 nanoparticles catalyzed H2O2 oxidation of Rhodamine B. Under the chosen conditions, the fluorescence intensity at 584 nm decreased when the concentration of H2O2 increased. The fluorescence quenching intensity is linear with the concentration of H2O2 in the range of 10–200 nmol/L. Thus, a new and simple and sensitive nanocatalytic fluorescence method was proposed for the determination of H2O2 in synthetic sample, with satisfactory results.  相似文献   
8.
This paper describes the preparation for the first time of lipobead-based micrometric fluorescence biosensors and the optimization of their analytical properties. The study focused on the well-established urea biosensors as a model system. Fluorescence-sensing lipobeads were prepared by coating carboxyl-functionalized silica microspheres with phospholipids. The enzyme urease and the pH indicator fluorescein-5-thiosemicarbazide were then attached covalently to the phospholipid membrane of the lipobeads. Urease converts urea to ammonia, which results in a pH increase in the analyte solution and to a urea concentration-dependent increase in the fluorescence intensity of the sensing lipobeads. Previous fluorescence-sensing lipobeads were synthesized by coating polystyrene particles with a phospholipid membrane. The membrane was physically attached to the particles and the fluorophores were entrapped in the membrane. In this study, we prepared improved fluorescence-sensing lipobeads by utilizing covalent chemistry to bind the phospholipid membrane to the silica particles and the fluorophores to the membrane. This led to improvement in the stability of the newly developed urea-sensing lipobeads compared to previously developed miniaturized fluorescence biosensors.  相似文献   
9.
We show that the eigenfunctions of Kohn-Sham equations can be decomposed as ■ = F ψ, where F depends on the Coulomb potential only and is locally Lipschitz, while ψ has better regularity than ■.  相似文献   
10.
In this paper, spectral collocation and Nyström methods for integral equations are discussed. Some multilevel correction schemes are presented for infinitely accelerating the covergence even if the exact solution is not so smooth.  相似文献   
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