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31.
Amogh Deshpande Srikanth K. Iyer 《Central European Journal of Operations Research》2009,17(2):219-228
We consider an enhancement of the credit risk+ model to incorporate correlations between sectors. We model the sector default rates as linear combinations of a common set
of independent variables that represent macro-economic variables or risk factors. We also derive the formula for exact VaR contributions at the obligor level. 相似文献
32.
Dispersion compensation up to the third order is experimentally demonstrated by using a dual-fibre stretcher combined with the coma of an imaging lens, in a fibre-based scan-free time domain optical coherence tomography system, leading to an axial resolution of less than 3 μm. 相似文献
33.
Jaya N. Iyer 《Proceedings of the American Mathematical Society》2002,130(4):959-962
We show that polarisations of type on -dimensional abelian varieties are never very ample, if . This disproves a conjecture of Debarre, Hulek and Spandaw. We also give a criterion for non-embeddings of abelian varieties into -dimensional linear systems.
34.
K. R. Krishna Iyer P. Neelakantan T. Radhakrishnan 《Journal of Polymer Science.Polymer Physics》1968,6(10):1747-1758
The Rayleigh-Gans theory of light scattering by a homogeneous cylinder has been applied to the case of scattering by a pad of fibers immersed in a liquid. The theory enables one to locate precisely the matching wavelength at which the mean refractive index of a sample of optically heterogeneous fibers coincides with that of an immersion medium. Thereby it offers a method of determining the mean refractive index. Besides, it facilitates a quantitative estimation of the variability of refractive index. The new technique has been used to study the birefringence of untreated cotton and ramie. The results are presented and discussed. 相似文献
35.
Utility of Zeo-Karb 226 and Dowex A-l for the separation of Tl and In at 5-ppm level from high-purity zinc and zinc-base alloys has been investigated. With Zeo-Karb 226 (NH(4)(+)), T1(+) is conveniently separated from these materials and also from many other cations, with l.0M ammonium nitrate as the eluent. It is subsequently determined with Rhodamine B. This separation principle is also applied to the analysis of Pb-Tl alloys. Both Tl and In (along with Fe) are preconcentrated on Zeo-Karb 226(H(+)) from a solution of the sample at pH 3.0. Suitable methods of subsequent determination of Tl and In are described. In the case of Dowex A-1(H(+)), Tl(+), In(3+), Fe(3+) and Cu(2+) are retained from a solution of the sample at pH 2.0. An o-phenanthroline solution at pH 2.0 elutes all but traces of Cu(2+). In(3+) along with Fe(3+) is eluted with l.0M hydrochloric acid. Finally, Tl is eluted with 2.0M hydrochloric acid containing sulphurous acid. 相似文献
36.
37.
Jaya N. Iyer 《Compositio Mathematica》2003,136(3):317-321
In this paper, we show that the Chern classes c
k
of the de Rham bundle
defined on any good toroidal compactification
of the moduli space of Abelian varieties of dimension g are zero in the rational Chow ring of
, for g=4, 5 and k>0. 相似文献
38.
Jaya N. Iyer 《Transactions of the American Mathematical Society》2003,355(8):3209-3216
We show that ample line bundles on a -dimensional simple abelian variety , satisfying 2^g\cdot g!$">, give projective normal embeddings, for all .
39.
We show that the exact energy eigenvalues and eigenfunctions of the Schrödinger equation for charged particles moving in certain class of non-central potentials can be easily calculated analytically in a simple and elegant manner by using Nikiforov and Uvarov (NU) method. We discuss the generalized Coulomb and harmonic oscillator systems. We study the Hartmann Coulomb and the ring-shaped and compound Coulomb plus Aharanov–Bohm potentials as special cases. The results are in exact agreement with other methods. 相似文献
40.
The synthesis of oligoethylene glycols of defined lengths possessing different end functionalities is described. The utility of these molecules towards the development of a generic membrane anchor is demonstrated. 相似文献