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101.
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Ralf T. Münnich Ekkehard W. Sachs Matthias Wagner 《Journal of Global Optimization》2012,52(3):471-485
Weighting is a common methodology in survey statistics to increase accuracy of estimates or to compensate for non-response.
One standard approach for weighting is calibration estimation which represents a common numerical problem. There are various
approaches in the literature available, but quite a number of distance-based approaches lack a mathematical justification
or are numerically unstable. In this paper we reformulate the calibration problem as a system of nonlinear equations. Although
the equations are lacking differentiability properties, one can show that they are semismooth and the corresponding extension
of Newton’s method is applicable. This is a mathematically rigorous approach and the numerical results show the applicability
of this method. 相似文献
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Alexander Higelin Ulf Sachs Sarah Keller Prof. Dr. Ingo Krossing 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(32):10029-10034
In a new oxidative route, Ag+[Al(ORF)4]? (RF=C(CF3)3) and metallic indium were sonicated in aromatic solvents, such as fluorobenzene (PhF), to give a precipitate of silver metal and highly soluble [In(PhF)n]+ salts (n=2, 3) with the weakly coordinating [Al(ORF)4]? anion in quantitative yield. The In+ salt and the known analogous Ga+[Al(ORF)4]? were used to synthesize a series of homoleptic PR3 phosphane complexes [M(PR3)n]+, that is, the weakly PPh3‐bridged [(Ph3P)3In–(PPh3)–In(PPh3)3]2+ that essentially contains two independent [In(PPh3)3]+ cations or, with increasing bulk of the phosphane, the carbene‐analogous [M(PtBu3)2]+ (M=Ga, In) cations. The MI? P distances are 27 to 29 pm longer for indium, and thus considerably longer than the difference between their tabulated radii (18 pm). The structure, formation, and frontier orbitals of these complexes were investigated by calculations at the BP86/SV(P), B3LYP/def2‐TZVPP, MP2/def2‐TZVPP, and SCS‐MP2/def2‐TZVPP levels. 相似文献
109.
M. K. Sachs M. R. Yoder D. L. Turcotte J. B. Rundle B. D. Malamud 《The European physical journal. Special topics》2012,205(1):167-182
Extreme events that change global society have been characterized as black swans. The frequency-size distributions of many
natural phenomena are often well approximated by power-law (fractal) distributions. An important question is whether the probability
of extreme events can be estimated by extrapolating the power-law distributions. Events that exceed these extrapolations have
been characterized as dragon-kings. In this paper we consider extreme events for earthquakes, volcanic eruptions, wildfires,
landslides and floods. We also consider the extreme event behavior of three models that exhibit self-organized criticality
(SOC): the slider-block, forest-fire, and sand-pile models. Since extrapolations using power-laws are widely used in probabilistic
hazard assessment, the occurrence of dragon-king events have important practical implications. 相似文献
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