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We briefly review the main developments of Bayesian dynamic models. The emphasis is on marketing applications. Typical examples in this area are discussed. The concepts of monitoring and intervention are carefully explained with illustrative examples and open source computational routines. We avoid algebraic developments and instead use graphical examples to illustrate theoretical aspects. Two real-world problems using Bayesian dynamic models are discussed. Finally, we describe recent developments and alternative proposals to formally address the dependence when dealing with the modeling of multiple time series.  相似文献   
73.
This paper is concerned with the existence and multiplicity of solutions for a class of problems involving the Φ-Laplacian operator with general assumptions on the nonlinearities, which include both semipositone cases and critical concave convex problems. The research is based on the subsupersolution technique combined with a truncation argument and an application of the Mountain Pass Theorem. The results in this paper improve and complement some recent contributions to this field.  相似文献   
74.
Decay studies of very neutron-deficient nuclei ranging from 39Ti to 49Ni have been performed during a projectile fragmentation experiment at the GANIL/LISE3 separator. For all nuclei studied in this work, 39, 40Ti, 42, 43Cr, 46Mn, 45, 46, 47Fe and 49Ni, half-lives and decay spectra have been measured. In a few cases, γ coincidence measurements helped to successfully identify the initial and final states of transitions. In these cases, partial decay scheme are proposed. For the most exotic isotopes, 39Ti, 42Cr, 45Fe and 49Ni, which are candidates for two-proton radioactivity from the ground state, no clear evidence of this process is seen in our spectra and we conclude rather on a delayed particle decay. Received: 26 July 2000 / Accepted: 20 December 2000  相似文献   
75.
We demonstrate that delta doping can be used to create a dimensionally confined region of metallic ferromagnetism in an antiferromagnetic (AFM) manganite host, without introducing any explicit disorder due to dopants or frustration of spins. Theoretical consideration of these additional carriers shows that they cause a local enhancement of ferromagnetic double exchange with respect to AFM superexchange, resulting in local canting of the AFM spins. This leads to a highly modulated magnetization, as measured by polarized neutron reflectometry. The spatial modulation of the canting is related to the spreading of charge from the doped layer and establishes a fundamental length scale for charge transfer, transformation of orbital occupancy, and magnetic order in these manganites. Furthermore, we confirm the existence of the canted, AFM state as was predicted by de Gennes [Phys. Rev. 118, 141 (1960)] but had remained elusive.  相似文献   
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In this work, we study and characterize the cholesteric sequence of phases (ChDr ? ChB ? ChD), where the first ChDr is the reentrant cholesteric discotic phase, ChB is the cholesteric biaxial phase and the second ChD is the cholesteric discotic phase. This sequence of phases is studied through polarized light microscopy and image processing technique, where, for the first time, the domains and borders of these transitions are established and characterized. They are also investigated and optically characterized throughout their textures.  相似文献   
80.
We investigate the matching, across cylindrical surfaces, of static cylindrically symmetric conformally flat spacetimes with a cosmological constant $\Lambda $ , satisfying regularity conditions at the axis, to an exterior Linet–Tian spacetime. We prove that for $\Lambda \le 0$ such matching is impossible. On the other hand, we show through simple examples that the matching is possible for $\Lambda >0$ . We suggest a physical argument that might explain these results.  相似文献   
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