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81.
In this paper, we present a Quasi-Monte Carlo approach for pricingEuropean-style Asian options, i.e. for options whose pay-offdepends on the average price of the underlying asset where theaverage is extended over a fixed period up to the maturity date.Following a recent development in mathematical finance, we assumethat the log returns of the asset are not normally but hyperbolicallydistributed. This hypothesis is approved by several authorswith different statistic tests on real financial data. The aimof this paper is to advance the hyperbolic model to the pricingof Asian options, since there only exist pricing formulae forplain vanilla options and some types of exotic options (e.g.power call options, barrier options) so far. We show how onecan obtain prices of general Asian options in such incompletemarkets in an efficient way. 相似文献
82.
83.
Jurgen HENNIG 《波谱学杂志》2002,19(1):88-89
MR Tomography has entered clinical practice in the early 1980 s with the introduction of the first commercial scanner. In its twenty years of history it went through several developmental cycles. 相似文献
84.
85.
Semicarbazide is a minor thermal decomposition product of azodicarbonamide used in the gaskets of certain food jars 总被引:1,自引:0,他引:1
Stadler RH Mottier P Guy P Gremaud E Varga N Lalljie S Whitaker R Kintscher J Dudler V Read WA Castle L 《The Analyst》2004,129(3):276-281
Evidence is presented for the first time showing that semicarbazide (SEM) is a minor thermal decomposition product of the blowing agent azodicarbonamide (ADC). A novel direct analytical method based on liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESIMS/MS) has been developed to determine SEM in foamed polyvinyl chloride (PVC) seals of metal lids, as well as in commercially available ADC. The direct LC-MS/MS method for gaskets entails extraction of the gaskets in hot water, addition of ((15)N(2)(13)C)-SEM as internal standard, and injection of an aliquot directly into the LC-MS system, achieving good sensitivity (S/N = 348 for 2 ng injected on-column) and monitoring three characteristic mass transitions (m/z 76-->31; 76 -->44; 76-->59). Semicarbazide can be detected in thermally treated ADC, reaching up to 0.93 mmol mol(-1) at 220 degrees C, as determined by the direct LC-MS/MS method. This new method is also compared to the classical derivatization method using 2-nitrobenzaldehyde (2-NBA) that is routinely employed to determine SEM as an indicator of the usage of the antimicrobial drug nitrofurazone, the use of which is not authorized in the European Union (EU). Both methods revealed proportional results, with approx. 3-fold higher levels recorded by the direct SEM approach, probably due to differences in the extraction procedures used. A limited survey of plastic seals from used press twist and twist-off metal lids on food jars (non-foamed and foamed) revealed levels of SEM ranging from 2 to 8689 microg kg(-1)(average = 1593 microg kg(-1), n= 57 determinations). 相似文献
86.
Pérez M Lombó F Zhu L Gibson M Braña AF Rohr J Salas JA Méndez C 《Chemical communications (Cambridge, England)》2005,(12):1604-1606
L- and D-stereoisomers of amicetose were generated by combining sugar biosynthesis genes from four different antibiotic gene clusters and both sugars were transferred to the elloramycin aglycone by the sugar flexible ElmGT glycosyltransferase. 相似文献
87.
We show that it is possible to make the Rabioscillations of the state of a two-level atomvisible by continuous measurement of theatomic energy. 相似文献
88.
89.
A deterministic model of tuberculosis without and with seasonality is designed and analyzed into its transmission dynamics.
We first present and analyze a tuberculosis model without seasonality, which incorporates the essential biological and epidemiological
features of the disease. The model is shown to exhibit the phenomenon of backward bifurcation, where a stable disease-free
equilibrium coexists with one or more stable endemic equilibria when the associated basic reproduction number is less than
unity. The statistical data of tuberculosis (TB) cases show seasonal fluctuations in many countries. Then, the extension of
our TB model by incorporating seasonality is developed and the basic reproduction ratio is defined. Parameter values of the
model are estimated according to demographic and epidemiological data in Cameroon. The simulation results are in good accordance
with the seasonal variation of the reported cases of active TB in Cameroon. 相似文献
90.
Synchronization processes in populations of locally interacting elements are the focus of intense research in physical, biological, chemical, technological and social systems. The many efforts devoted to understanding synchronization phenomena in natural systems now take advantage of the recent theory of complex networks. In this review, we report the advances in the comprehension of synchronization phenomena when oscillating elements are constrained to interact in a complex network topology. We also take an overview of the new emergent features coming out from the interplay between the structure and the function of the underlying patterns of connections. Extensive numerical work as well as analytical approaches to the problem are presented. Finally, we review several applications of synchronization in complex networks to different disciplines: biological systems and neuroscience, engineering and computer science, and economy and social sciences. 相似文献