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991.
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?GR 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:B2σ?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?GR 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   
992.
This paper is concerned with large-O 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   
993.
吴晓飞  朱加民  马正义 《中国物理》2005,14(12):2395-2401
By means of a Painlevé-Baicklund transformation and a multi-linear separation-of-variable approach, abundant localized coherent excitations of a modified Broer-Kaup system are derived. There appear possible phase shifts for the interactions of the (2+1)-dimensional novel localized structures, which are discussed in this paper.  相似文献   
994.
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   
995.
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   
996.
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   
997.
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   
998.
We prove a Lyapunov type theorem for modular functions on complemented lattices.  相似文献   
999.
Let be a Hilbert space of functions analytic on a plane domain such that for every in the functional of evaluation at is bounded. Assume further that contains the constants and admits multiplication by the independent variable z, Mz, as a bounded operator. We give sufficient conditions for Mz to be reflexive.Received: 17 February 2004  相似文献   
1000.
We characterize the relation between the geometrical properties of Weyl manifolds and the algebraic properties of the Weyl algebras (§1) and the deformation algebras associated to two conformal Weyl connections (§2). The last section is devoted to the study of the Weyl-Lyra algebras associated to a conformal Weyl connection and a conformal semisymmetric connection.  相似文献   
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