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21.
We propose a minimum mean absolute error linear interpolator (MMAELI), based on theL
1 approach. A linear functional of the observed time series due to non-normal innovations is derived. The solution equation
for the coefficients of this linear functional is established in terms of the innovation series. It is found that information
implied in the innovation series is useful for the interpolation of missing values. The MMAELIs of the AR(1) model with innovations
following mixed normal andt distributions are studied in detail. The MMAELI also approximates the minimum mean squared error linear interpolator (MMSELI)
well in mean squared error but outperforms the MMSELI in mean absolute error. An application to a real series is presented.
Extensions to the general ARMA model and other time series models are discussed.
This research was supported by a CityU Research Grant and Natural Science Foundation of China. 相似文献
22.
Johan van Benthem 《Logica Universalis》2007,1(1):125-138
We prove new Lindstr?m theorems for the basic modal propositional language, and for some related fragments of first-order
logic. We find difficulties with such results for modal languages without a finite-depth property, high-lighting the difference
between abstract model theory for fragments and for extensions of first-order logic. In addition we discuss new connections
with interpolation properties, and the modal invariance theorem.
Mathematics Subject Classification (2000): Primary 03B45; Secondary 03C95 相似文献
23.
介绍了以PIC16F873单片机为控制核心的汽车组合仪表板控制系统的设计,简述了汽车组合仪表板的基本构成,介绍了汽车组合仪表板控制系统的组成和各部分功能,给出了数据采集处理电路、电源电路等部分硬件电路设计方案,并阐述了一些软件设计算法,如分段插补法和用于平滑指针的软件设计算法等。 相似文献
24.
Gašper Jaklič Jernej Kozak Marjeta Krajnc Vito Vitrih Emil Žagar 《Numerical Algorithms》2007,45(1-4):49-60
In this paper, three-pencil lattices on triangulations are studied. The explicit representation of a lattice, based upon barycentric
coordinates, enables us to construct lattice points in a simple and numerically stable way. Further, this representation carries
over to triangulations in a natural way. The construction is based upon group action of S
3 on triangle vertices, and it is shown that the number of degrees of freedom is equal to the number of vertices of the triangulation.
相似文献
25.
V. M. Murzina 《Algebra and Logic》2007,46(6):409-418
We study into the question whether calculi associated with Ershov topological spaces possess Craig’s interpolation property.
Supported by RFBR grant No. 06-01-00358, by INTAS grant No. 04-77-7080, and by the Council for Grants (under RF President)
and State Aid of Fundamental Science Schools, project NSh-4787.2006.1.
__________
Translated from Algebra i Logika, Vol. 46, No. 6, pp. 745–762, November–December, 2007. 相似文献
26.
A Taylor dispersion tube has been used to measure mutual diffusion in aqueous solutions of glycine hydrochloride at 25°C and concentrations from 0.0005 to 0.5 M. Analysis of the dispersion profiles shows that the diffusion of glycine hydrochloride (GlyHCl) produces a subtantial additional flow of hydrochloric acid that is liberated by the dissociation: GlyH+ + Cl- Gly + H+ + Cl-. Diffusion in this system is, therefore, a ternary process described by the equations J
1(GlyHCl) = – D
11C
1 – D
12C
2 and J
2(HCl) = –D
21C
1 – D
22C
2 for the coupled fluxes of total glycine hydrochloride (1) and hydrochloric acid (2) components. The ratio D
21/D
11 of measured diffusion coefficients indicates that up to two moles of HCl are cotransported per mole of GlyHCl. Although protonated glycine diffuses with relatively mobile Cl– counterions, the main diffusion coefficient of glycine hydrochloride, D
11, is lower than or nearly identical to the diffusion coefficient of aqueous glycine. A model for the diffusion of protonated solutes is developed to interpret this result and the large coupled flows of HCl. Diffusion coefficients are also reported for the aqueous hydrochlorides of 3- and 4-aminobenzoic acids. 相似文献
27.
28.
Trigonometric wavelets for Hermite interpolation 总被引:4,自引:0,他引:4
Ewald Quak. 《Mathematics of Computation》1996,65(214):683-722
The aim of this paper is to investigate a multiresolution analysis of nested subspaces of trigonometric polynomials. The pair of scaling functions which span the sample spaces are fundamental functions for Hermite interpolation on a dyadic partition of nodes on the interval . Two wavelet functions that generate the corresponding orthogonal complementary subspaces are constructed so as to possess the same fundamental interpolatory properties as the scaling functions. Together with the corresponding dual functions, these interpolatory properties of the scaling functions and wavelets are used to formulate the specific decomposition and reconstruction sequences. Consequently, this trigonometric multiresolution analysis allows a completely explicit algorithmic treatment.
29.
30.
We consider the problem of interpolating scattered data in 3 by analmost geometrically smoothGC
2 surface, where almostGC
2 meansGC
2 except in a finite number of points (the vertices), where the surface isGC
1. A local method is proposed, based on employing so-called degenerate triangular Bernstein-Bézier patches. We give an analysis of quintic patches forGC
1 and patches of degree eleven for almostGC
2 interpolation. 相似文献