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151.
Konstantin Volosov Gautam Mitra Fabio Spagnolo Cormac Lucas 《Computational Optimization and Applications》2005,32(1-2):179-207
In this paper we formulate a model for foreign exchange exposure management and (international) cash management taking into consideration random fluctuations of exchange rates. A vector error correction model (VECM) is used to predict the random behaviour of the forward as well as spot rates connecting dollar and sterling. A two-stage stochastic programming (TWOSP) decision model is formulated using these random parameter values. This model computes currency hedging strategies, which provide rolling decisions of how much forward contracts should be bought and how much should be liquidated.The model decisions are investigated through ex post simulation and backtesting in which value at risk (VaR) for alternative decisions are computed. The investigation (a) shows that there is a considerable improvement to “spot only” strategy, (b) provides insight into how these decisions are made and (c) also validates the performance of this model. 相似文献
152.
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154.
Chalcogenide glass fibers have been successfully used for remote spectroscopy, temperature sensing and CO2 laser power delivery. In bulk form, chalcogenide glass is the most promising candidate for replacing the expensive germanium lenses for thermal imaging. 相似文献
155.
K. Lützenkirchen J. V. Kratz G. Wirth W. Brüchle L. Dörr K. Sümmerer R. Lucas J. Poitou C. Grégoire S. Bjørnholm 《Zeitschrift für Physik A Hadrons and Nuclei》1985,322(3):529-530
The integral β?-spectra of235U and239Pu fission products have been measured with a plastic scintillator telescope at an external neutron guide tube at the high flux reactor of the ILL in Grenoble. The highly enriched targets (150 – 800 γg/cm2) were placed in a fission chamber at a distance of approximately 110 m from the reactor core. From the measured beta-spectra absolute counting rates per MeV and fission have been calculated, which are compared with the results of earlier experiments of other authors and with recent theoretical calculations. 相似文献
156.
Sans résuméAvec 3 figures 相似文献
157.
Jorge C.G. Calado Edmundo J.S. Gomes de Azevedo Virgílio A.M. Soares Klaus Lucas Keshawa P. Shukla 《Fluid Phase Equilibria》1984,16(2):171-183
The total vapour pressure of the xenon + methyl chloride system has been measured as a function of composition at 175.44 and 182.32 K. The resulting data have been used to evaluate the excess Gibbs functions GE at the same temperatures. The excess enthalpy and excess molar volume have also been measured at 182.32 K. The system shows large positive deviations from Raoult's law but negative volumes on mixing. These results are compared with theoretical predictions of a recent molecular theory and of standard engineering methods. The calculations show the superiority of the molecular theory over more empirical procedures such as those based on the Redlich-Kwong equation of state or the regular-solution model. 相似文献
158.
Using a molecular perturbation theory based on an equation of state for pure argon, excess properties and vapor-liquid equilibria are predicted for various binary mixtures composed of weakly nonspherical molecules. The results are rather satisfactory and generally much better than obtained using typical empirical methods. It is further demonstrated that a binary parameter in the dispersion energy results in only modest improvement 相似文献
159.
Stability of hypersurfaces with constant mean curvature 总被引:12,自引:0,他引:12
160.
We study immersed prescribed mean curvature compact hypersurfaces with boundary in Hn+1(-1). When the boundary is a convex planar smooth manifold with all principal curvatures greater than 1, we solve a nonparametric Dirichlet problem and use this, together with a general flux formula, to prove a parametric uniqueness result, in the class of all immersed compact hypersurfaces with the same boundary. We specialize this result to a constant mean curvature, obtaining a characterization of totally umbilic hypersurface caps. 相似文献