We present a fast algorithm for computing the global crystal basis of the basic
-module. This algorithm is based on combinatorial techniques which have been developed for dealing with modular representations of symmetric groups, and more generally with representations of Hecke algebras of typeA at roots of unity. We conjecture that, upon specializationq1, our algorithm computes the decomposition matrices of all Hecke algebras at anth root of 1.Partially supported by PRC Math-Info and EEC grant n0 ERBCHRXCT930400. 相似文献
Practical solutions to the production scheduling problem must provide two broad capabilities:
i)
an ability to efficiently generate schedules that reflect the actual constraints and objectives of the manufacturing environment, and
ii)
an ability to incrementally revise these schedules over time in response to unexpected executional circumstances. In this paper, we advocate a common view of predictive and reactive scheduling as an incremental problem solving process that is opportunistically focused by characteristics of the current solution constraints.
We describe the architecture of OPIS (opportunistic intelligent scheduler), which defines a general framework for configuring scheduling systems according to this view. We then examine the scheduling knowledge (e.g. analysis and scheduling methods, schedule generation or revision strategies) that is exploited within this architecture by the current OPIS scheduler. Experimental studies with the OPIS scheduler have demonstrated the potential of this constraint-directed scheduling methodology in both predictive and reactive scheduling contexts. 相似文献
Six docking programs (FlexX, GOLD, ICM, LigandFit, the Northwestern University version of DOCK, and QXP) were evaluated in terms of their ability to reproduce experimentally observed binding modes (poses) of small-molecule ligands to macromolecular targets. The accuracy of a pose was assessed in two ways: First, the RMS deviation of the predicted pose from the crystal structure was calculated. Second, the predicted pose was compared to the experimentally observed one regarding the presence of key interactions with the protein. The latter assessment is referred to as interactions-based accuracy classification (IBAC). In a number of cases significant discrepancies were found between IBAC and RMSD-based classifications. Despite being more subjective, the IBAC proved to be a more meaningful measure of docking accuracy in all these cases. 相似文献
The reaction of 7,7a,8,9,10,12-hexahydrobenzo[h]pyrrolo [1,2-b]isoquinoline-7,10-dione 2 with sodium azide in sulfuric acid afforded the unexpected cyano derivative 5 . The proposed structure for 5 is supported by 13C nmr, 1H nmr and HMBC spectra. 相似文献
Six new phenol derivatized hexahydropyrimidines (1,3-bis-(2-hydroxy-3,5-di(X)benzyl) hexahydropyrimidine and 5,5′-dimethyl-1,3-bis-(2-hydroxy-3,5-di(X)benzyl) hexahydropyrimidine where X = Me, t-Bu, and Cl) were synthesized in one-pot in 33-79% yield using Mannich condensations. 相似文献
A series of pilot plant experiments have been conducted to compare the performance of a system utilizing two percolation reactors in series to a single reactor system. Although theoretically capable of producing higher glucose yields or concentrations, the two-reactor system concentrations were approximately the same and the yields were considerably lower than those from the single reactor study. An associated kinetics study found the glucose degradation kinetics to be accelerated by chromium ions, but this effect was greatly reduced in the presence of wood. The presence of metal surfaces also increased the rate of degradation even without large ion concentrations. The poor performance of the reactor system is proposed to be caused by intraparticle glucose diffusion effects and the catalytic effect on glucose degradation reactions of chromium ions from the corrosion of stainless steel by the acid. Strategies for reducing the effects of these phenomena on PBR performance are presented.
[reaction: see text] The synthesis and photonic and liquid-crystalline properties of a novel oligo biphenylene vinylene (OBV) chromophore with an extended pi-electron system are reported; the compound exhibits high fluorescence, a large two-photon absorption cross-section, and two- and three-dimensional liquid-crystalline mesophases. 相似文献
We report (1 + 1) resonance-enhanced multiphoton ionization spectra for clusters of para-fluorotoluene (pFT)n (n = 1–11). After n = 2, the spectra appear to have converged in appearance, suggestive of a dimer chromophore, with weak bonding for subsequent additions of pFT molecules. The spectra also indicate dramatic, vibrational-mode-sensitive changes of oscillator strength between the monomer and the clusters. We also briefly describe the results of probing different parts of the expansion, and varying the laser power. 相似文献