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991.
The concept of super value nodes was established to allow dynamic programming to be performed within the theory of influence diagrams and to reduce the computational complexity in solving problems by means of influence diagrams. This paper is focused on how influence diagrams with super value nodes are affected by the presence of imprecise information. We analyze how to reduce the complexity when evaluating an influence diagram in this framework by modelling these kinds of nodes and random magnitudes in terms of fuzzy random variables. Finally, an applied example of the theoretical results is developed. 相似文献
992.
José Luis Palacios Nancy Lopes Garcia 《Journal of Mathematical Analysis and Applications》2003,286(1):230-236
Using the electric approach, we derive exact and asymptotic closed form formulas for hitting times in symmetric cases of the Moran's genetics model. 相似文献
993.
Alberto Sturaro Giorgio Parvoli Lucio Doretti Sergio Daolio 《Journal of mass spectrometry : JMS》1991,26(11):967-971
Air and waste samples coming from poultry breeding farms have been analysed by means of thermal desorption coupled to the gas chromatographic/mass spectrometric technique. The solid samples not only showed the presence of organic compounds such as acids, sulphides, benzopyrroles and phenols originated by anaerobic biotransfor-mation of the natural products, but also the occurrence of anti-oxidant substances: 2,6-di-tert-butylcresol, 2,6-di-tert-butylphenol and two of their oxidation derivatives. In the air, four artificial benzoquinones were detected, two of which had already been identified in the solid waste. In this work, the mechanism by which oxidized compounds are formed, is suggested. 相似文献
994.
The Direction of Time: From the Global Arrow to the Local Arrow 总被引:1,自引:0,他引:1
Mario Castagnino Luis Lara Olimpia Lombardi 《International Journal of Theoretical Physics》2003,42(10):2487-2504
In this paper we discuss the traditional approaches to the problem of the arrow of time. On the basis of this discussion we adopt a global and nonentropic approach, according to which the arrow of time has a global origin and is an intrinsic, geometrical feature of space-time. Finally, we show how the global arrow is translated into local terms as a local time-asymmetric flux of energy. 相似文献
995.
Miguel Carda Florenci Gonz lez Santiago Rodrí guez J. Alberto Marco 《Tetrahedron: Asymmetry》1992,3(12):1511-1514
The diastereoselectivity of the addition of several organometallic reagents to the carbonyl group of protected
- and
-erythrulose derivatives has been investigated. Tertiary alcohols are stereoselectively formed, the diastereomeric ratio being markedly dependent on the reagent type, solvent and temperature. 相似文献
996.
Luis M. Murillo-Mora Katsuyuki Okada Toshio Honda Jumpei Tsujiuchi 《Optical Review》1994,1(2):195-197
An image processing technique to display a distortion-free reconstructed image from a rainbow type conical holographic stereogram is proposed. The method consists of forming a new set of 2D images from the original set by applying an image process. The image processing method is made through ray tracing equations. The results show that the performance of the proposed method is good as it removes distortion of the image. 相似文献
997.
partially supported by DGICYT 相似文献
998.
999.
Alberto Calabri 《Annali di Matematica Pura ed Applicata》2002,181(4):365-387
Following the ideas of Castelnuovo and Enriques, we classify the birational equivalence classes of double planes which are
rational or ruled surfaces. In order to do this, we prove that the vanishing of the m-adjoint linear system to the branch curve of the canonical resolution of a double plane, for m≥2, is a necessary and sufficient condition for the ruledness of the double plane.
Received: May 18, 2000?Published online: October 30, 2002
Partially supported by E.C. project EAGER, contract n. HPRN-CT-2000-00099 相似文献
1000.
A new methodology for the determination of the fluorescence quantum yield of dyes adsorbed onto microcrystalline cellulose is presented and applied to rhodamine 101, cresyl violet and auramine O. It is based on a previously reported method by Ruetten and Thomas (J. Phys. Chem., 1998, 102, 598-606), which is not applicable to the dyes used in the present study. It uses ground-state diffuse reflectance spectra obtained with and without filters, which prevents the luminescence of the dye from reaching the integrating sphere and the photodetector. New equations are presented here, correcting for the fluorescence emission of the dye, which depends on the detector sensitivity. Cut-on filters, which have a transmittance close to unity in the absorption region, and close to zero in the emission region, of the dye are used to obtain corrected reflectance spectra. The influence of the substrate was also taken into account. This methodology may be applied to other probes and surfaces or emissions of a different nature (i.e., phosphorescence or delayed fluorescence), and constitutes a very simple and general procedure to solve the important problem of luminescence quantum yield determination of probes adsorbed onto solid powdered surfaces. 相似文献