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31.
32.
Reiner Horst 《The Journal of the Operational Research Society》1984,35(4):327-335
The relationships between multiple optimal dual solutions of a convex programming problem and the corresponding primal optimal value function are established by straightforward arguments on known results in duality theory. The subsequent discussion includes a demonstration that one-sided shadow prices can be found by solving a linear programming problem, conditions for the uniqueness and validity of the classical shadow price interpretation and a specialization of the results to the linear programming case. 相似文献
33.
We study a combinatorially defined double complex structure on the ordered chains of any simplicial complex. Its columns are related to the cell complex Kn whose face poset is isomorphic to the subword ordering on words without repetition from an alphabet of size n. This complex is shellable and as an application we give a representation theoretic interpretation for derangement numbers and a related symmetric function considered by Désarménien and Wachs [11].
We analyze the two spectral sequences arising from the double complex in the case of the bar resolution for a group. This spectral sequence converges to the cohomology of the group and provides a method for computing group cohomology in terms of the cohomology of subgroups. Its behavior is influenced by the complex of oriented chains of the simplicial complex of finite subsets of the group, and we examine the Ext class of this complex. 相似文献
34.
In this note we show that various branch and bound methods for solving continuous global optimization problems can be readily adapted to the discrete case. As an illustration, we present an algorithm for minimizing a concave function over the integers contained in a compact polyhedron. Computational experience with this algorithm is reported. 相似文献
35.
CFD-simulation of a circulating fluidized bed riser 总被引:1,自引:0,他引:1
In the current work,a model of the fluid mechanics in the riser of a circulating fluidized bed(CFB)has been implemented using computational fluid dynamics(CFD).The model developed shall be used in future as the basis of 3D-reactor model for the simulation of large scale CFB combustors.The two-fluid model(TFM)approach is used to represent the fluid mechanics involved in the flow.The computational implementation is accomplished by the commercial software FLUENT.Different closure formulations are tested on a simplified geometry.Two different turbulence formulations,namely the swirl modified RNG k–εmodel and the Realizable k–εmodel,are tested in combination with two different approaches to solid phase turbulence,namely the dispersion and per phase approach.One focus of the current work is put on the study of different drag correlations.Besides the drag correlations by Syamlal et al.[Syamlal,M.,Rogers, W.,O’Brien,T.J.(1993).MFIX documentation theory guide.Technical Report DOE/METC-94/1004,U.S. Department of Energy(DOE).Morgantown Energy Technology Center:Morgantown,WV]and Gidaspow [Gidaspow,D.(1994).Multiphase flow and fluidization.New York:Academic Press]the EMMS model has been used to determine the momentum exchange between the two phases.The resulting formulation is then used to simulate a 1-m×0.3-m cold CFB setup and is validated by experimental results[Schlichthrle, P.(2000).Fluid dynamics and mixing of solids and gas in the bottom zone of circulating fluidized beds. Unpublished doctoral dissertation,Technische Universitaet Hamburg-Harburg,Shaker Verlag:Aachen]. 相似文献
36.
Detection of a single photon escaping an optical cavity QED system prepares a nonclassical state of the electromagnetic field. The evolution of the state can be modified by changing the drive of the cavity. For the appropriate feedback, the conditional state can be captured (stabilized) and then released. This is observed by a conditional intensity measurement that shows suppression of vacuum Rabi oscillations for the length of the feedback pulse and their subsequent return. 相似文献
37.
D. Hildebrandt H. Grote A. Herrmann M. Laux P. Pech H.-D. Reiner H. Wolff 《等离子体物理论文集》1988,28(1):85-95
It is shown that the efflux of impurities injected into the core plasma can be detected by collector probes in the scrape-off plasma. The time evolution, orientation and radial dependences of these effluxes allow to conclude on the impurity confinement in the core plasma and the scrape-off plasma. Moreover, recycling effects can also be measured. 相似文献
38.
Rudolf Taube Jörg-Peter Gehrke Reiner Radeglia 《Journal of organometallic chemistry》1985,291(1):101-115
The reaction of the η3-allylbis(triarylphosphite)nickel(II) complexes with butadiene under chain propagation to give the polybutadienyl complex, [3-RC3H4Ni(P(OAr)3)2]PF6, was monitored by 31P NMR spectroscopy. In the case of the triphenylphosphite complex both the anti- and the syn-configuration could be identified by means of their different AB spectra. The anti-syn isomerization, the higher reactivity of the thermodynamically more stable syn-form, and the formation of the anti-structure as a result of each individual butadiene insertion step was also proved. From these observations an experimentally well-grounded mechanism of the trans regulation with the anti-syn isomerization as the rate-determining step could be derived for the first time. 相似文献
39.
The title compound 1 has been isolated from and its structure deduced; 1 was synthesised from shanzhiside methyl ester. 相似文献
40.