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991.
992.
Stochastic programming problems have very large dimension and characteristic structures which are tractable by decomposition. We review basic ideas of cutting plane methods, augmented Lagrangian and splitting methods, and stochastic decomposition methods for convex polyhedral multi-stage stochastic programming problems.  相似文献   
993.
994.
We consider four models of random directed multigraphs with n labeled vertices of out-degree d. First we establish formal relationships between our models with respect to exact and asymptotic (as n → ∞) probabilities of possessing a graph monotone property. We also study the asymptotic behavior of the strength of connectivity of the underlying simple graphs when d = o(n). © 1993 John Wiley & Sons, Inc.  相似文献   
995.
The program ORTOCARTAN can calculate the curvature tensors (Riemann, Ricci, Einstein and Weyl) from a given orthonormal tetrad representation of the metric tensor. It was first announced in 1981, but since then has undergone several extensions and transplants onto other computers. This article reviews the current status of the program from the point of view of a user. The following topics are discussed: the problems that the program can be applied to, the special features of the algorithms that make the program powerful, the technical requirements to run the program and two simple examples of applications.  相似文献   
996.
997.
Differential cross sections forγ-transitions to 12 states in28Si following nonresonant proton capture in27Al nuclei (E p=1,625 keV) were measured and analysed in terms of the direct-semidirect model. The experimental data are reproduced only when the complex coupling constant with the GDR is enhanced for thef partial wave in the entrance channel.  相似文献   
998.
For the polycrystalline samples of Mn1?xCuxCr2S4 (x = 0.85, 0.90, 0.95) the magnetization was measured in the temperature range between 77 K and the Curie temperature, TC, using a magnetic balance (Faraday's method) and pulsed magnetic fields up to 2.0 T. The magnetic susceptibility was measured between TC and about 600 K. The Curie temperatures were obtained using the kink point method.In the temperature range between 4.2 and 77 K the magnetization was measured in stationary magnetic fields up to 14 T. The data indicate a noncollinear ferrimagnetic structure. The compounds under investigation can be treated as CuCr2S4 slightly doped with Mn, with a valence distribution Mn2+1?xCu1+xCr3+2?xCr4+xS2?4.  相似文献   
999.
The differential cross section dσdt′ for the charge-exchange process π+p → π0 (π+p) at 8, 16 and 23 GeV/c is presented for several regions of the π+p effective mass. It is found that the dip at t′ ≈ 0.6 (GeV/c)2 which is observed in the Δ(1236) mass band becomes a less pronounced structure in the higher mass regions. However, while the slope of the dσdt′ distributions in the near-forward direction decreases strongly with increasing π+p mass, there is no evidence that the observed structure moves to higher values of t′ as the π+p mass increases. These results are consistent with a Regge-exchange picture where the position of the dip is determined by the exchanged trajectory, but are inconsistent with a simple geometrical picture.  相似文献   
1000.
Anion-exchangers loaded with SPADNS or Orange II or SPADNS + Nitroso-R salt are used for selective separation of bismuth and cadmium, which are then determined by AAS.  相似文献   
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