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991.
Suppose that {z(t)} is a non-Gaussian vector stationary process with spectral density matrixf(λ). In this paper we consider the testing problemH: ∫π−π K{f(λ)} dλ=cagainstA: ∫π−π K{f(λ)} dλ≠c, whereK{·} is an appropriate function andcis a given constant. For this problem we propose a testTnbased on ∫π−π K{f(λ)} dλ=c, wheref(λ) is a nonparametric spectral estimator off(λ), and we define an efficacy ofTnunder a sequence of nonparametric contiguous alternatives. The efficacy usually depnds on the fourth-order cumulant spectraf4Zofz(t). If it does not depend onf4Z, we say thatTnis non-Gaussian robust. We will give sufficient conditions forTnto be non-Gaussian robust. Since our test setting is very wide we can apply the result to many problems in time series. We discuss interrelation analysis of the components of {z(t)} and eigenvalue analysis off(λ). The essential point of our approach is that we do not assume the parametric form off(λ). Also some numerical studies are given and they confirm the theoretical results. 相似文献
992.
The spontaneous volume magnetostriction is calculated for Y(Fe1?xCox)2 and Zr(Fe1?xCox)2 in the simple itinerant-electron model. The density of states for various compositions is calculated by the recursion method. The calculated results on the composition dependence of the spontaneous volume magnetostriction are shown to be consistent with the experimental ones. 相似文献
993.
994.
Masao Fukushima 《Journal of Computational and Applied Mathematics》1990,30(3):329-339
This paper presents a conjugate gradient method for solving systems of linear inequalities. The method is of dual optimization type and consists of two phases which can be implemented in a common framework. Phase 1 either finds the minimum-norm solution of the system or detects the inconsistency of the system. In the latter event, the method proceeds to Phase 2 in which an approximate least-squares solution to the system is obtained. The method is particularly suitable to large scale problems because it preserves the sparsity structure of the problem. Its efficiency is shown by computational comparisons with an SOR type method. 相似文献
995.
We will show that a generalization of the well-known Rogers-Ramanujan identities by use of special determinants can be restated as a counting problem of Young diagrams under a cyclic equivalent relation. And we find a very strange observation. 相似文献
996.
997.
998.
A new glass capillary microelectrode for L-glutamate is described using pulled glass capillaries (tip size, approximately 12.5 microm) with a very small volume (approximately 2 microl) of inner solution containing glutamate oxidase (GluOx) and ascorbate oxidase. The operation of the electrode is based on capillary action that samples L-glutamate into the inner solution. The enzyme reaction by GluOx generates hydrogen peroxide that is detected at an Os-gel-HRP polymer modified Pt electrode in a three-electrode configuration. The amperometric response behavior of the electrode was characterized in terms of the capillarity, response time, sensitivity and selectivity for measurements of L-glutamate. The currents at 0 V vs. Ag/AgCl increased linearly with the L-glutamate concentration from 10 to 150 microM for in vitro and in situ calibrations. The response was highly selective to L-glutamate over ascorbate, dopamine, serotonin and other amino acids. The detection of L-glutamate in the extracellular fluids of different regions of mouse hippocampal slices under stimulation of KCl was demonstrated. 相似文献
999.
In the normal phase (where no dynamical fermion mass generation occurs) of the D-dimensional quantum electrodynamics with Nf flavors of fermions, we derive an integral equation which should be satisfied by (the inverse of) the wave function renormalization of the fermion in the Landau gauge. For this we use the inverse Landau-Khalatnikov transformation connecting the nonlocal gauge with the Landau gauge. This leads to a similar equation for the running flavor number in the framework of the 1/Nf resumed Schwinger-Dyson equation. Solving the equation analytically and numerically, we study the infrared behavior and the critical exponent of the 3-dimensional QED (QED3). This confirms that the flavor number in QED3 runs according to the β function which is consistent with the asymptotic freedom as that in 4-dimensional QCD. 相似文献
1000.
T Katsu K Sanchika H Okazaki T Kondo T Kayamoto Y Fujita 《Chemical & pharmaceutical bulletin》1991,39(7):1651-1654
Amphiphile-induced tetraethylammonium ion (TEA+) uptake into human erythrocytes was examined along with cell shape change. A TEA(+)-sensitive electrode was used to determine the amount of uptake. TEA+ was preferentially incorporated into erythrocytes when amphiphiles changed cell shape to an invaginated form. This was contrasted with the release of acetylcholinesterase outside cells which occurred markedly with the amphiphiles, causing the crenated form. It was suggested that the invagination of erythrocyte membrane stimulated the formation of vacuoles, in which TEA+ existing in an external medium was entrapped. 相似文献