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991.
Marc Prevost 《Journal of Computational and Applied Mathematics》1983,9(4):333-346
The interpolation of the function x → 1/(1 ? xt) generating the series f(t) = ∑∞i = 0citi at the zeros of an orthogonal polynomial with respect to a distribution d α satisfying some conditions will give us a process for accelerating the convergence of fn(t) = ∑ni = 0citi. Then, we shall see that the polynomial of best approximation of x → 1/(1 ? xt) over some interval or its development in Chebyshev polynomials Tn or Un are only particular cases of the main theorem.At last, we shall show that all these processes accelerate linear combinations with positive coefficients of totally monotonic and oscillating sequences. 相似文献
992.
993.
Denote by σ the subspace of Hilbert space {(xi)?l2:xi=0 for all but finitely many i}. Examples of cell-like decompositions of σ are constructed that have decomposition spaces that are not homeomorphic to σ. At one extreme is a cell-like decomposition G of σ produced using ghastly finite dimensional examples such that the decomposition space σ?G contains no embedded 2-cell but (σ?G)× is homeomorphic to σ. At the other extreme is a cell-like decomposition G of σ satisfying: (a) the nondegeneracy set NG={g?G:g≠point} consists of countably many arcs (necessarily tame); (b) the nondegeneracy set NG is a closed subset of the decomposition space σ?G; (c) each map f:B2→σ?G of a 2-cell into σ?G can be approximated arbitrarily closely by an embedding; (d) σ?G is not homeomorphic to σ but (σ?G)× is homeomorphic to σ. The fact that both conditions (a) and (b) can be satisfied (and have (d) hold) is directly attributable to σ’s incompleteness as a topological space. 相似文献
994.
This paper is concerned with large- error estimates concerning convergence in distribution as well as norm convergence for Banach space-valued martingale difference sequences. Indeed, two general limit theorems equipped with rates of convergence for such difference sequences are established. Applications of these lead to the central limit theorem and the weak law of large numbers with rates for Banach space-valued martingales. 相似文献
995.
Yeinzon?RodríguezEmail author Carlos?QuimbayEmail author 《Foundations of Physics Letters》2005,18(7):581-602
No Heading Several works analyzing the new physics contributions from the Left-Right Symmetric Model to the CP violation phenomena in
the neutral B mesons can be found in the literature. These works exhibit interesting and experimentally sensible deviations
from the Standard Model predictions but at the expense of considering a low right scale υR around 1 TeV. However, when we stick to the more conservative estimates for υR, which say that it must be at least 107 GeV, no experimentally sensible deviations from the Standard Model appear for indirect CP violation. This estimate for υR arises when the generation of neutrino masses is considered. In spite of the fact that this scenario is much less interesting
and says nothing new about both the CP violation phenomenon and the structure of the Left-Right Symmetric Model, this possibility
must be taken into account for the sake of completeness and when considering the see-saw mechanism that provides masses to
the neutrino sector.
1 Associate researcher of the Centro Internacional de Física, Ciudad
Universitaria, Bogotá D.C., Colombia. 相似文献
996.
Fawaz?S.?Al-AnziEmail author Ali?Allahverdi 《Journal of Mathematical Modelling and Algorithms》2005,4(4):435-453
This research addresses the scheduling problem of multimedia object requests, which is an important problem in information
systems, in particular, for World Wide Web applications. The performance measure considered is the variance of response time
which is crucial as end users expect fair treatment to their service requests. This problem is known to be NP-hard. The literature
survey indicates that two heuristics have been proposed to solve the problem. In this paper, we present a new heuristic, a
hybrid evolutionary heuristic, which is shown to perform much better than the two existing ones, e.g., the overall average
errors of the existing ones are 1.012 and 2.042 while the error of the proposed hybrid evolutionary heuristic is 0.154. 相似文献
997.
We prove the existence of positive symmetric solutions to the semilinear elliptic problem
in both the radial case N = k ≥ 3 and the cylindrical case N ≥ k + 3 ≥ 6. The potential V is measurable, positive and it is only required to satisfy a mild integrability condition. The nonlinearity is continuous
and has a doublepower behavior, super-critical near the origin and sub-critical at infinity. If f is odd, we show that the radial problem has infinitely many solutions. In proving these results we exploit the compactness
of suitable restrictions of the embedding
Supported by MIUR, project “Variational Methods and Nonlinear Differential Equations”. 相似文献
998.
Laurence A.J. Garvie Huifang Xu Yifeng Wang Robert L. Putnam 《Journal of Physics and Chemistry of Solids》2005,66(5):902-905
Pyrochlore with mixed-valence Ce was synthesized by firing and annealing Ce(NO3)4, TiO2, and Ca(OH)2 with a stoichiometry of CaCeTi2O7 at 1300 °C. The product contains Ce-pyrochlore, Ce-rich perovskite, CeO2 (cerianite), and minor CaO. Electron energy-loss spectroscopy (EELS) revealed both Ce4+ and Ce3+ in the Ce-pyrochlore with a Ce4+ to total Ce (Ce4+/ΣCe) of 0.80 giving . Cerium in the perovskite and cerianite is dominated by Ce3+ and Ce4+, respectively. High-resolution transmission electron microscope (HRTEM) images show that the boundary between Ce-pyrochlore and Ce-rich perovskite is semi-coherently bonded. The orientational relationship between the neighboring Ce-pyrochlore and Ce-rich perovskite is not random. Ce-pyrochlore (CaCeTi2O7) is a chemical analogue for CaPuTi2O7, which is a proposed ceramic waste form for deposition of excess weapons-usable Pu in geological repositories. It is postulated, based on the presence of Ce3+ in the Ce-pyrochlore, that neutron poisons such as Gd can be incorporated into the CaPuTi2O7 phase. 相似文献
999.
The continuous-wave laser properties of an efficient diode-pumped Nd:GdVO4 crystal operating at formed with a simple plane-concave cavity have been studied. With the incident pump power of 21 W, an output power of 6.9 W was obtained, giving an optical conversion efficiency of 32.8% and a slope efficiency of 35.3%. The laser characterization of two different Nd3+-doped concentration of Nd:GdVO4 crystals were studied. 相似文献
1000.
Anna Avallone 《Rendiconti del Circolo Matematico di Palermo》2004,53(2):195-204
We prove a Lyapunov type theorem for modular functions on complemented lattices. 相似文献