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931.
Jules Sadefo Kamdem 《Computing and Visualization in Science》2007,10(4):197-210
In this paper, we generalize the Linear VaR method from portfolios with normally distributed risk factors to portfolios with
mixture of elliptically distributed ones. We treat both the Expected Shortfall and the Value-at-Risk of such portfolios. Special
attention is given to the particular case of a mixture of multivariate t-distributions.
This is a part of J. SADEFO-KAMDEM PhD Thesis[12] of the Université de Reims, France . It has been presented at the workshop
on modelling and computation in Financial Engineering at Bad Herrenalb, Germany May 6-8, 2003. The author is an associate
professor at the Department of mathematics, université d’Evry Val d’Essonne. 相似文献
932.
Trust on a Nationwide Scale 总被引:1,自引:0,他引:1
Singapore is a small island nation with roughly 4.5 million inhabitants, but it has a highly developed international economy based on trade, services, and knowledge management. Singapore launched its lofty goals by defining the nationpsilas e-security. Current research in the Singaporean telecommunications and IT security community attempts to model such peer-to-peer ad hoc transactions and leverage the existing standard infrastructure described in this article. 相似文献
933.
934.
Compared to other fields of engineering, in mechanical engineering, the Discrete Element Method (DEM) is not yet a well known
method. Nevertheless, there is a variety of simulation problems where the method has obvious advantages due to its meshless
nature. For problems where several free bodies can collide and break after having been largely deformed, the DEM is the method
of choice. Neighborhood search and collision detection between bodies as well as the separation of large solids into smaller
particles are naturally incorporated in the method. The main DEM algorithm consists of a relatively simple loop that basically
contains the three substeps contact detection, force computation and integration. However, there exists a large variety of
different algorithms to choose the substeps to compose the optimal method for a given problem. In this contribution, we describe
the dynamics of particle systems together with appropriate numerical integration schemes and give an overview over different
types of particle interactions that can be composed to adapt the method to fit to a given simulation problem. Surface triangulations
are used to model complicated, non-convex bodies in contact with particle systems. The capabilities of the method are finally
demonstrated by means of application examples.
Commemorative Contribution. 相似文献
935.
936.
937.
938.
E. M. Gavrishchuk E. Yu. Vilkova O. V. Timofeev U. P. Borovskikh E. L. Tikhonova 《Inorganic Materials》2007,43(6):579-583
Chemical interaction between polished surfaces of polycrystalline zinc selenide and inorganic acid solutions of various concentrations has been studied. 相似文献
939.
V. V. Ustinov A. B. Rinkevich L. N. Romashev E. A. Kuznetsov 《Technical Physics Letters》2007,33(9):771-774
The reflection of electromagnetic waves in the millimeter wave band from Fe/Cr nanostructures has been studied. It is established that the giant magnetoresistance (GMR) in the nanostructure leads to an increase in the reflection and a decrease in the transmission of microwaves, while the magnetic resonance leads to a decrease in both the reflection and transmission coefficients. 相似文献
940.
I. V. Oryshich N. E. Poryadchenko N. P. Brodnikovskii 《Powder Metallurgy and Metal Ceramics》2004,43(9-10):497-503
We have studied the oxidation resistance of chromium intermetallics: TiCr2, HfCr2, and ZrCr2, in the temperature interval 873–1473 K with isothermal holding of the specimens for up to 20 h. We have shown that the intermetallics TiCr2 and HfCr2 are oxidized 2–3 times more slowly than pure titanium and hafnium, but more than 1–2 orders of magnitude faster than chromium at T≤1273 K and 4–6 times faster at 1473 K. In this temperature interval, the intermetallic ZrCr2 is rapidly oxidized at an increasing rate as the heating temperature rises. The scaling resistance of intermetallics of Group IV d metals with chromium is determined by formation of scales in which the major role is played by the oxides TiO2, HfO2, and ZrO2, with weak protective properties. 相似文献