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111.
112.
Victor Guillemin Eva Miranda Ana Rita Pires 《Bulletin of the Brazilian Mathematical Society》2011,42(4):607-623
In this short note we give a complete characterization of a certain class of compact corank one Poisson manifolds, those equipped with a closed one-form defining the symplectic foliation and a closed two-form extending the symplectic form on each leaf. If such a manifold has a compact leaf, then all the leaves are compact, and furthermore the manifold is a mapping torus of a compact leaf. These manifolds and their regular Poisson structures admit an extension as the critical hypersurface of a b-Poisson manifold as we will see in [9]. 相似文献
113.
In this paper the complementary hyperstructure obtained from a multiplicative hyperring is considered. Furthermore a characterization for such hyperstructures obtained starting from a strongly distributive multiplicative hyperring is given. 相似文献
114.
Antonio Boccuto Anna Rita Sambucini 《Rendiconti del Circolo Matematico di Palermo》1925,49(2):395-396
In [3] we did not give explicitly the definition of measurability for realvalued functions, with respect to finitely additive measures with values in a Dedekind complete Riesz space. We note that, in [3], all involved functions are intended to be measurable. We now report the definition of measurability, which we gave in [2] (Definition 3.2). 相似文献
115.
Rita Giuliano Antonini Yuriy Kozachenko Andrei Volodin 《Journal of Mathematical Analysis and Applications》2008,338(2):1188-1203
The almost sure convergence of weighted sums of φ-subgaussian m-acceptable random variables is investigated. As corollaries, the main results are applied to the case of negatively dependent and m-dependent subgaussian random variables. Finally, an application to random Fourier series is presented. 相似文献
116.
Since the permutation decoding algorithm is more efficient the smaller the size of the PD-set, it is important for the applications to find small PD-sets. A lower bound on the size of a PD-set is given by Gordon. There are examples for PD-sets, but up to now there is no method known to find PD-sets. The question arises whether the Gordon bound is sharp. To handle this problem we introduce the notion of antiblocking system and we show that there are examples where the Gordon bound is not sharp. 相似文献
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119.
José Craveirinha Rita Girão-Silva João Clímaco 《Central European Journal of Operations Research》2008,16(1):79-105
MPLS (Multiprotocol Label Switching) enables the utilisation of explicit routes and other advanced routing mechanisms in multiservice
packet networks, capable of dealing with multiple and heterogeneous QoS (Quality of Service) parameters. Firstly the paper
presents a discussion of conceptual and methodological issues raised by multiobjective routing optimisation models for MPLS
networks. The major contribution is the proposal of a multiobjective routing optimisation framework for MPLS networks. The
major features of this modelling framework are: the formulation of a three-level hierarchical routing optimisation problem
including network and service performance objectives, the inclusion of fairness objectives in the different levels of optimisation
and a two-level stochastic representation of the traffic in the network (traffic flow and packet stream levels). A variant
of the general model for two classes of traffic flows, QoS traffic and Best Effort traffic, is also presented. Finally a stochastic
teletraffic modelling approach, underlying the optimisation model, is fully described.
Work partially supported by programme POSI of the III EC programme cosponsored by FEDER and national funds. 相似文献
120.
Torres MF Sales PS de Rossi RH Fernández MA 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):17858-17866
The mixed system of a nonionic hydrocarbon surfactant, polyoxyethylene (23) lauryl ether (Brij-35), and a perfluorinated surfactant, perfluorononanoic acid, was investigated by a combination of methods. The critical micelle concentrations (cmc's) have been determined over a wide range of sample compositions by fluorescence and UV-visible spectrophotometry using pyrene and N-(4-nitrophenyl) perfluorononanamide, respectively, as molecular probes. The values of the cmc's obtained were considerably different with the two techniques employed. Measurements of the (19)F nuclear magnetic resonance chemical shift of the same mixtures showed two breaks in the plots of Δδ(f) versus molar fraction of the perfluorinated surfactant. Conductivity and surface tension measurements also showed two breaks. The behavior is attributed to the formation of mixed micelles that change their composition when the fraction of the fluorinated compound increases and some segregation of the fluorinated compound takes place at a high total surfactant concentration. 相似文献