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1.
Jose Manuel Corcuera Joao Guerra David Nualart Wim Schoutens 《Applied Mathematics and Optimization》2006,53(3):279-309
In this paper we consider the optimal investment problem in a market where the stock price process is modeled by a geometric
Levy process (taking into account jumps).
Except for the geometric Brownian model and the geometric Poissonian model, the
resulting models are incomplete and there are many equivalent martingale measures.
However, the model can be completed by the so-called power-jump assets. By doing this we allow investment in these new assets
and we can try to maximize the expected utility of these portfolios. As particular cases we obtain the optimal portfolios
based in stocks
and bonds, showing that the new assets are superfluous for certain martingale measures
that depend on the utility function we use. 相似文献
2.
We give a small functorial algebraic model for the 2-stage Postnikov section of the K-theory spectrum of a Waldhausen category and use our presentation to describe the multiplicative structure with respect to biexact functors. 相似文献
3.
4.
Fernando M. Lanas Janete H. Y. Vilegas Srgio Martins Elaine A. F. Gobato 《Journal of separation science》1994,17(4):237-244
An overview is presented of the analytical approaches developed by our research group over the last ten years for analysis of alternative fuel, both biomass and fossil. The alternative fuels are analyzed successively by PLC-8 (preparative liquid chromatography–group-type) fractionation and high resolution gas chromatography. Some of the possibilities for fractionation and characterization of alternative fuels are herein exemplified with sugar cane bagasse pyrolysis products. 相似文献
5.
M. Trinidad Menarguez Fernando Soria 《Rendiconti del Circolo Matematico di Palermo》1992,41(3):342-352
In this paper we study the behavior of the constants which appear in the weak type (1, 1) inequalities for maximal convolution
operators by means of discrete methods.
One of the first applications of these techniques will give us a very simple proof of the ergodic theorem. We also present
partial results in order to investigate the best constant in the weak type (1, 1) inequality for the Hardy-Littlewood centered
maximal operator in dimension one. In dimension bigger than one we also obtain some lower bounds for that constant. 相似文献
6.
Formulas for calculating the spectral characteristics of waveguide arrays, which are incorporated into waveguide spectrum analyzers based on planar waveguides, channel waveguides, and fiber optical waveguides, are derived taking into account the contribution of both the waveguide dispersion and the material dispersion to the dispersion factor. These formulas are used to study the dependence of the dispersion factor on the waveguide-system parameters for specific models of waveguide arrays. It is shown that consideration of contributions of the waveguide dispersion and material dispersion can affect profoundly the spectral characteristics of waveguide arrays. 相似文献
7.
8.
Eleonora Catsigeras Jean-Marc Gambaudo Fernando Moreira 《Proceedings of the American Mathematical Society》1998,126(1):297-304
We show that, among area contracting embeddings of the 2-disk, infinitely renormalizable maps with a bounded geometry either have positive topological entropy or correspond to a cascade of period doubling.
9.
In this paper we address a two-dimensional (2D) orthogonal packing problem, where a fixed set of small rectangles has to be placed on a larger stock rectangle in such a way that the amount of trim loss is minimized. The algorithm we propose hybridizes a placement procedure with a genetic algorithm based on random keys. The approach is tested on a set of instances taken from the literature and compared with other approaches. The computation results validate the quality of the solutions and the effectiveness of the proposed algorithm. 相似文献
10.
Enrique Saldívar‐Guerra Jos Bonilla Gregorio Zacahua Martha Albores‐Velasco 《Journal of polymer science. Part A, Polymer chemistry》2006,44(24):6962-6979
Mechanisms and simulations of the induction period and the initial polymerization stages in the nitroxide‐mediated autopolymerization of styrene are discussed. At 120–125 °C and moderate 2,2,4,4‐tetramethyl‐1‐piperidinyloxy (TEMPO) concentrations (0.02–0.08 M), the main source of radicals is the hydrogen abstraction of the Mayo dimer by TEMPO [with the kinetic constant of hydrogen abstraction (kh)]. At higher TEMPO concentrations ([N?] > 0.1 M), this reaction is still dominant, but radical generation by the direct attack against styrene by TEMPO, with kinetic constant of addition kad, also becomes relevant. From previous experimental data and simulations, initial estimates of kh ≈ 1 and kad ≈ 6 × 10?7 L mol?1 s?1 are obtained at 125 °C. From the induction period to the polymerization regime, there is an abrupt change in the dominant mechanism generating radicals because of the sudden decrease in the nitroxide radicals. Under induction‐period conditions, the simulations confirm the validity of the quasi‐steady‐state assumption (QSSA) for the Mayo dimer in this regime; however, after the induction period, the QSSA for the dimer is not valid, and this brings into question the scientific basis of the well‐known expression kth[M]3 (where [M] is the monomer concentration and kth is the kinetic constant of autoinitiation) for the autoinitiation rate in styrene polymerization. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6962‐6979, 2006 相似文献