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441.
In this paper, the exact order of simultaneous approximation and Voronovskaja kind results with quantitative estimate for a new type of complex Durrmeyer polynomials, attached to analytic functions in compact disks are obtained. In this way, we put in evidence the overconvergence phenomenon for this kind of Durrmeyer polynomials, namely the extensions of approximation properties with exact quantitative estimates, from the real interval [0, 1] to compact disks in the complex plane. 相似文献
442.
We construct the matrix generalization of the N=2 supersymmetric GNLS hierarchies. This is done by exhibiting the corresponding matrix super Lax operators in terms of N=2 superfields in two different superfield bases. We present the second Hamiltonian structure and discrete symmetries. We then extend our discussion by conjecturing the Lax operators of different reductions of the N=2 supersymmetric matrix KP hierarchy and discuss the simplest examples. 相似文献
443.
Sorin G. Gal 《Complex Analysis and Operator Theory》2012,6(2):515-527
Attaching to a compact disk
[`(\mathbbDr)]{\overline{\mathbb{D}_{r}}} in the quaternion field
\mathbbH{\mathbb{H}} and to some analytic function in Weierstrass sense on
[`(\mathbbDr)]{\overline{\mathbb{D}_{r}}} the so-called q-Bernstein operators with q ≥ 1, Voronovskaja-type results with quantitative upper estimates are proved. As applications, the exact orders of approximation
in
[`(\mathbbDr)]{\overline{\mathbb{D}_{r}}} for these operators, namely
\frac1n{\frac{1}{n}} if q = 1 and
\frac1qn{\frac{1}{q^{n}}} if q > 1, are obtained. The results extend those in the case of approximation of analytic functions of a complex variable in disks
by q-Bernstein operators of complex variable in Gal (Mediterr J Math 5(3):253–272, 2008) and complete the upper estimates obtained for q-Bernstein operators of quaternionic variable in Gal (Approximation by Complex Bernstein and Convolution-Type Operators, 2009; Adv Appl Clifford Alg, doi:, 2011). 相似文献
444.
Thomas Ducret Bruno Sorin Anne Marie Vacher Pierre Vacher 《Journal of fluorescence》2002,12(2):253-258
We have examined the spatiotemporal aspects of PRL-induced Ca2+ signals using high-speed fluo-3 confocal imaging. We found that PRL stimulated Ca2+ entry and intracellular Ca2+ mobilization. Ca2+ influx was seen as a peripheral increase in [Ca2+]i without amplification in the nucleus region. Intracellular Ca2+ mobilization was seen as a propagating intracellular calcium wave with a strong amplification in the nuclear region. The amplitude of PRL-induced Ca2+ increases would be sufficient to stimulate cell proliferation. Furthermore, PRL induced an increase in [3H]thymidine incorporation. These data suggest that PRL would be able to induce mitogenesis through a Ca2+-dependent pathway. 相似文献
445.
We study compact complex 3-manifolds M admitting a (locally homogeneous) holomorphic Riemannian metric g. We prove the following: (i) If the Killing Lie algebra of g has a non trivial semi-simple part, then it preserves some holomorphic Riemannian metric on M with constant sectional curvature; (ii) If the Killing Lie algebra of g is solvable, then, up to a finite unramified cover, M is a quotient Γ\G, where Γ is a lattice in G and G is either the complex Heisenberg group, or the complex SOL group.
S. Dumitrescu was partially supported by the ANR Grant BLAN 06-3-137237. 相似文献
446.
Stoica-Guzun A Stroescu M Jinga S Jipa I Dobre T Dobre L 《Ultrasonics sonochemistry》2012,19(4):909-915
The effect of ultrasonic irradiation (40 kHz) on the calcium carbonate deposition on bacterial cellulose membranes was investigated using calcium chloride (CaCl2) and sodium carbonate (Na2CO3) as starting reactants. The composite materials containing bacterial cellulose-calcium carbonate were characterized by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and color measurements. The polymorphs of calcium carbonate that were deposited on bacterial cellulose membranes in the presence or in the absence of ultrasonic irradiation were calcite and vaterite. The morphology of the obtained crystals was influenced by the concentration of starting solutions and by the presence of ultrasonic irradiation. In the presence of ultrasonic irradiation the obtained crystals were bigger and in a larger variety of shapes than in the absence of ultrasounds: from cubes of calcite to spherical and flower-like vaterite particles. Bacterial cellulose could be a good matrix for obtaining different types of calcium carbonate crystals. 相似文献
447.
Dr. S. Sorin 《International Journal of Game Theory》1979,8(4):217-223
We consider repeated two-person zero-sum games with lack of information on both sides. If the one shot game is played sequentially, it is proved that the sequencev n is monotonic,v n being the value of then shot game. Moreover the speed of convergence is bounded byK/n, and this is the best bound. 相似文献
448.
The complex projective space CP2 is a classical example of Einstein metric in Riemannian geometry. Moreover, beside this property, it has other interesting geometrical properties: it is a symmetric space, and a C manifold. We would like to know whether there is an Einstein metric of Randers type on CP2 with similar properties. Based on some the generalization of Zermelo navigation problem for Finsler manifolds we construct such Randers metric on CP2 and study some of its geometrical properties. 相似文献
449.
450.