3,047 research outputs found
A continuous mapping theorem for the smallest argmax functional
This paper introduces a version of the argmax continuous mapping theorem that
applies to M-estimation problems in which the objective functions converge to a
limiting process with multiple maximizers. The concept of the smallest
maximizer of a function in the d-dimensional Skorohod space is introduced and
its main properties are studied. The resulting continuous mapping theorem is
applied to three problems arising in change-point regression analysis. Some of
the results proved in connection to the d-dimensional Skorohod space are also
of independent interest
Individual Transferable Grounds in a Community Managed Artisanal Fishery
Environmental Economics and Policy, Production Economics,
Special Section Introduction: The Role of Economics in Mitigating Unsustainability of Fisheries: Dealing with Ecosystems, Governance, and Environmental Fluctuations
Environmental Economics and Policy,
Direct evidence of intervalence charge-transfer states of Eu-doped luminescent materials
Direct evidence is given for the existence of intervalence charge transfer (IVCT) states of Eu2+/Eu3+ pairs in Eu-doped CaF2 , SrF2, and BaF2 . They are detected in diffuse reflectance spectra. In doped materials, IVCT states, in which an electron transfer occurs between two metal sites differing only in oxidation state, are rather difficult to observe because the absorption bands are extremely broad and flat, their intensity is low, and no emission follows the IVCT absorptions. Their assignment as IVCT states is provided by state-of-the-art multiconfigurational ab initio calculations. Although IVCT states of lanthanide-doped materials have largely been overlooked so far, they can cause luminescence quenching and even complete luminescence excitation loss. Their direct observation and independent assignment in classical dopant (Eu) and hosts (CaF2, SrF2, BaF2) are very significant: They suggest that the occurrence of IVCT states in other lanthanide-activated materials is very likely overlooked and their impact is ignored
Parallel, linear-scaling building-block and embedding method based on localized orbitals and orbital-specific basis sets
We present a new linear scaling method for the energy minimization step of
semiempirical and first-principles Hartree-Fock and Kohn-Sham calculations. It
is based on the self-consistent calculation of the optimum localized orbitals
of any localization method of choice and on the use of orbital-specific basis
sets. The full set of localized orbitals of a large molecule is seen as an
orbital mosaic where each tessera is made of only a few of them. The orbital
tesserae are computed out of a set of embedded cluster pseudoeigenvalue coupled
equations which are solved in a building-block self-consistent fashion. In each
iteration, the embedded cluster equations are solved independently of each
other and, as a result, the method is parallel at a high level of the
calculation. In addition to full system calculations, the method enables to
perform simpler, much less demanding embedded cluster calculations, where only
a fraction of the localized molecular orbitals are variational while the rest
are frozen, taking advantage of the transferability of the localized orbitals
of a given localization method between similar molecules. Monitoring single
point energy calculations of large poly(ethylene oxide) molecules and three
dimensional carbon monoxide clusters using an extended Huckel Hamiltonian are
presented.Comment: latex, 15 pages, 10 figures, accepted for publication in J.Chem.Phy
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