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排序方式: 共有223条查询结果,搜索用时 31 毫秒
21.
Betuel?CanhangaEmail author Anatoliy?Malyarenko Jean-Paul?Murara Ying?Ni Sergei?Silvestrov 《Methodology and Computing in Applied Probability》2017,19(4):1075-1087
Multiscale stochastic volatilities models relax the constant volatility assumption from Black-Scholes option pricing model. Such models can capture the smile and skew of volatilities and therefore describe more accurately the movements of the trading prices. Christoffersen et al. Manag Sci 55(2):1914–1932 (2009) presented a model where the underlying price is governed by two volatility components, one changing fast and another changing slowly. Chiarella and Ziveyi Appl Math Comput 224:283–310 (2013) transformed Christoffersen’s model and computed an approximate formula for pricing American options. They used Duhamel’s principle to derive an integral form solution of the boundary value problem associated to the option price. Using method of characteristics, Fourier and Laplace transforms, they obtained with good accuracy the American option prices. In a previous research of the authors (Canhanga et al. 2014), a particular case of Chiarella and Ziveyi Appl Math Comput 224:283–310 (2013) model is used for pricing of European options. The novelty of this earlier work is to present an asymptotic expansion for the option price. The present paper provides experimental and numerical studies on investigating the accuracy of the approximation formulae given by this asymptotic expansion. We present also a procedure for calibrating the parameters produced by our first-order asymptotic approximation formulae. Our approximated option prices will be compared to the approximation obtained by Chiarella and Ziveyi Appl Math Comput 224:283–310 (2013). 相似文献
22.
Mole RA Stride JA Henry PF Hoelzel M Senyshyn A Alberola A Gómez Garcia CJ Raithby PR Wood PT 《Inorganic chemistry》2011,50(6):2246-2251
We report the magnetic structure of two of the magnetically ordered phases of Co(3)(OH)(2)(C(4)O(4))(2)·3H(2)O, a coordination polymer that consists of a triangular framework decorated with anisotropic Co(II) ions. The combination of neutron diffraction experiments and magnetic susceptibility data allows us to identify one phase as displaying spin idle behavior, where only a fraction of the moments order at intermediate temperatures, while at the lowest temperatures the system orders fully. This novel magnetic behavior is discussed within the framework of a simple Hamiltonian and representational analysis and rationalizes this multiphase behavior by considering the combination of frustration and anisotropy. 相似文献
23.
Buschmann H Dölle J Berendts S Kuhn A Bottke P Wilkening M Heitjans P Senyshyn A Ehrenberg H Lotnyk A Duppel V Kienle L Janek J 《Physical chemistry chemical physics : PCCP》2011,13(43):19378-19392
The solid lithium-ion electrolyte "Li(7)La(3)Zr(2)O(12)" (LLZO) with a garnet-type structure has been prepared in the cubic and tetragonal modification following conventional ceramic syntheses routes. Without aluminium doping tetragonal LLZO was obtained, which shows a two orders of magnitude lower room temperature conductivity than the cubic modification. Small concentrations of Al in the order of 1 wt% were sufficient to stabilize the cubic phase, which is known as a fast lithium-ion conductor. The structure and ion dynamics of Al-doped cubic LLZO were studied by impedance spectroscopy, dc conductivity measurements, (6)Li and (7)Li NMR, XRD, neutron powder diffraction, and TEM precession electron diffraction. From the results we conclude that aluminium is incorporated in the garnet lattice on the tetrahedral 24d Li site, thus stabilizing the cubic LLZO modification. Simulations based on diffraction data show that even at the low temperature of 4 K the Li ions are blurred over various crystallographic sites. This strong Li ion disorder in cubic Al-stabilized LLZO contributes to the high conductivity observed. The Li jump rates and the activation energy probed by NMR are in very good agreement with the transport parameters obtained from electrical conductivity measurements. The activation energy E(a) characterizing long-range ion transport in the Al-stabilized cubic LLZO amounts to 0.34 eV. Total electric conductivities determined by ac impedance and a four point dc technique also agree very well and range from 1 × 10(-4) Scm(-1) to 4 × 10(-4) Scm(-1) depending on the Al content of the samples. The room temperature conductivity of Al-free tetragonal LLZO is about two orders of magnitude lower (2 × 10(-6) Scm(-1), E(a) = 0.49 eV activation energy). The electronic partial conductivity of cubic LLZO was measured using the Hebb-Wagner polarization technique. The electronic transference number t(e-) is of the order of 10(-7). Thus, cubic LLZO is an almost exclusive lithium ion conductor at ambient temperature. 相似文献
24.
Virgil Percec Anatoliy V. Popov Ernesto Ramirez‐Castillo Oliver Weichold 《Journal of polymer science. Part A, Polymer chemistry》2003,41(21):3283-3299
The first example of living radical polymerization of vinyl chloride carried out in water at 25 °C is reported. This polymerization was initiated by iodoform and catalyzed by nascent Cu0 produced by the disproportionation of CuI in the presence of strongly CuII binding ligands such as tris(2‐aminoethyl)amine or polyethyleneimine. The resulting poly(vinyl chloride) was free of structural defects, had controlled molecular weight and narrow molecular weight distribution, contained two ~CHClI active chain ends, and had a higher syndiotacticity (62%) than the one obtained by conventional free‐radical polymerization at the same temperature (56%). This novel polymerization proceeds, most probably, by a combination of competitive pathways that involves activation by single electron transfer mediated by nascent Cu0 and degenerative chain transfer. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3283–3299, 2003 相似文献
25.
Anatoliy D. Rikun 《Journal of Global Optimization》1997,10(4):425-437
Convex envelopes of multilinear functions on a unit hypercube arepolyhedral. This well-known fact makes the convex envelopeapproximation very useful in the linearization of non-linear 0–1programming problems and in global bilinear optimization. This paperpresents necessary and sufficient conditions for a convex envelope to be apolyhedral function and illustrates how these conditions may be used inconstructing of convex envelopes. The main result of the paper is a simpleanalytical formula, which defines some faces of the convex envelope of amultilinear function. This formula proves to be a generalization of the wellknown convex envelope formula for multilinear monomial functions. 相似文献
26.
Oleg I. Belous Anatoliy I. Fisun Anatoliy A. Kirilenko Viktor K. Korneenkov Vladimir S. Miroshnichenko 《International Journal of Infrared and Millimeter Waves》1997,18(2):445-461
Theoretical and experimental results of an investigation into a new resonant system have been obtained. This system is named
the sphere-corner-echelette open resonator (SCEOR) due to the employment of a mirror that was formed by two echelettes at
the angles of 45° to the resonator axis. It turns ont that this resonator is excited on the specific modes not unique to others
oscillating systems.
There are presented the results of the experimental research of the orotron oscillator with the SCEOR. The spectrum of this
device contains only the fundamental modes such as theT E M
006,T E M
007,T E M
008. The efficiency of the orotron is improved, when all other factors are the same the orotron with a much used sphere-cylindrical
open resonator. 相似文献
27.
Anatoliy Malyarenko 《Journal of Theoretical Probability》2008,21(2):459-475
We derive a series expansion for the multiparameter fractional Brownian motion. The derived expansion is proven to be rate
optimal.
This work is supported in part by the Foundation for Knowledge and Competence Development and Sparbanksstiftelsen Nya. 相似文献
28.
Petr A. Obraztsov Anatoliy. A. Sirotkin Elena D. Obraztsova Yuri P. Svirko Sergey V. Garnov 《Optical Review》2010,17(3):290-293
We demonstrate the passive mode-locking of a diode-pumped Nd+3:YAG (central wavelength: 1.32 μm; pulse duration: 50 ps; output energy: up to 70 μJ) laser using a polymer film containing
single-wall carbon nanotubes. The mode-locking regime is stable at a pump repetition rate of up to 1 kHz. We also investigate
the temporal evolution of the light-induced absorption change of the polymer film containing carbon nanotubes in the spectral
range of 1.3–1.5 μm by femtosecond time-resolved pump-probe measurements. The measurements reveal that light-induced transmission
exhibits fast and slow components that last 280 fs and more than 10 ps, respectively. The third-order susceptibility of the
polymer film containing single wall carbon nanotubes is as high as 10−11 esu. 相似文献
29.
Li F Buchnev O Cheon CI Glushchenko A Reshetnyak V Reznikov Y Sluckin TJ West JL 《Physical review letters》2006,97(14):147801
We investigated the physical properties of low concentration ferroelectric nematic colloids, using calorimetry, optical methods, infrared spectroscopy, and capacitance studies. The resulting homogeneous colloids possess a significantly amplified nematic orientational coupling. We find that the nematic orientation coupling increases by approximately 10% for particle concentrations of 0.2%. A manifestation of the increased orientational order is that the clearing temperature of a nematic colloid increases by up to 40 degrees C compared to the pure liquid crystal host. A theoretical model is proposed in which the ferroelectric particles induce local dipoles whose effective interaction is proportional to the square of the orientational order parameter. 相似文献
30.
The Lagrangian and Hamiltonian properties of classical electrodynamics models and their associated Dirac quantizations are
studied. Using the vacuum field theory approach developed in (Prykarpatsky et al. Theor. Math. Phys. 160(2): 1079–1095, 2009 and The field structure of a vacuum, Maxwell equations and relativity theory aspects. Preprint ICTP) consistent canonical
Hamiltonian reformulations of some alternative classical electrodynamics models are devised, and these formulations include
the Lorentz condition in a natural way. The Dirac quantization procedure corresponding to the Hamiltonian formulations is
developed. The crucial importance of the rest reference systems, with respect to which the dynamics of charged point particles
is framed, is explained and emphasized. A concise expression for the Lorentz force is derived by suitably taking into account
the duality of electromagnetic field and charged particle interactions. Finally, a physical explanation of the vacuum field
medium and its relativistic properties fitting the mathematical framework developed is formulated and discussed. 相似文献