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21.
Andy Buckley Hendrik Hoeth Heiko Lacker Holger Schulz Jan Eike von Seggern 《The European Physical Journal C - Particles and Fields》2010,65(1-2):331-357
In this article we describe Professor, a new program for tuning model parameters of Monte Carlo event generators to experimental data by parameterising the per-bin generator response to parameter variations and numerically optimising the parameterised behaviour. Simulated experimental analysis data is obtained using the Rivet analysis toolkit. This paper presents the Professor procedure and implementation, illustrated with the application of the method to tunes of the Pythia 6 event generator to data from the LEP/SLD and Tevatron experiments. These tunes are substantial improvements on existing standard choices, and are recommended as base tunes for LHC experiments, to be themselves systematically improved upon when early LHC data is available. 相似文献
22.
We study a central bank intervention (CBI) problem in the foreign exchange market when the exchange rate follows a jump-diffusion process and show that the optimal CBI policy is a control-band policy. Our main contribution is a rigorous proof of the existence and uniqueness of the optimal CBI policy. 相似文献
23.
24.
Ice structuring proteins - a new name for antifreeze proteins 总被引:1,自引:0,他引:1
Antifreeze proteins (AFPs) have been reported in the academic literature for many years, and are increasingly arousing interest in the technical and popular media, particularly because of their potential applications. However, the term "antifreeze" does not always accurately describe their natural function, or their application in frozen systems, where they do not prevent freezing, but control the size, shape and aggregation of ice crystals. We survey the properties and applications of AFPs and propose a more generally applicable name based on the fact that all AFPs bind to ice and consequently influence crystal growth and interactions: "Ice Structuring Proteins". 相似文献
25.
Richard F. Smith Allen S. Craig Lorrene A. Buckley Richard R. Soelch 《Tetrahedron letters》1979,20(43):4193-4196
Thermolysis of 1,1-dimethyl-1-benzyl-2-(iminophenylmethyl)hydrazinium hydroxide inner salt gave dimethylamine, 2,4,6-triphenyl-s-triazine and 2,4,6-triphenyl-1,2-dihydro-s-triazine. 相似文献
26.
Joseph D. Tanzer Buckley Crist William W. Graessley 《Journal of Polymer Science.Polymer Physics》1989,27(4):859-874
The effect of plastic deformation on the chain dimensions of polymers in the semicrystalline state was investigated using linear hydrogenated polybutadiene (HPB), a model ethylene/butene-1 copolymer having about 40% crystallinity at room temperature. Dilute blends of deuterium-labeled chains with various molecular weights (20,000 ≤ M ≤ 214,000) in the same unlabeled matrix (M = 95,000) were uniaxially stretched at 25°C to extension ratios of α = 2.4 and 4.4. Radius of gyration normal to the stretch direction R⊥ was measured for the labeled chains by small-angle neutron scattering. The molecular extension ratio inferred from these data αm = R/R was significantly smaller than α for short chains (M < 50,000) but increased to the affine range αm = α for M > 100,000. This variation in αm/α closely parallels the molecular weight dependence of mechanical strength and ductility in HPB over the same range. 相似文献
27.
R.G. Buckley 《Journal of Non》1980,37(2):231-240
The paper extends an earlier study of the far infrared properties of a series of evaporated amorphous GeGa alloys. The results of temperature dependent dc resistivity and near infrared and visible optical experiments are presented. Since the properties of amorphous films are dependent on the preparation conditions, a technique has been developed in which four samples of varying composition are prepared in the same evaporation. The far infrared data indicate that a significant fraction of Ga atoms dissolve in a-Ge with four-fold coordination. However, there is also indirect evidence of mixed valence. 相似文献
28.
[reaction: see text] A range of cis-substituted olefins has been epoxidized with a new dihydroisoquinolinium salt catalyst, using tetraphenylphosphonium monoperoxysulfate as the stoichiometric oxidant, giving ee's of up to 97%. The reaction has been used as the key step in an enantioselective synthesis of the antihypertensive agent levcromakalim. 相似文献
29.
Self-similar evolution of parabolic pulses in a laser 总被引:1,自引:0,他引:1
Self-similar propagation of ultrashort, parabolic pulses in a laser resonator is observed theoretically and experimentally. This constitutes a new type of pulse shaping in mode-locked lasers: in contrast to the well-known static (solitonlike) and breathing (dispersion-managed soliton) pulse evolutions, asymptotic solutions to the nonlinear wave equation that governs pulse propagation in most of the laser cavity are observed. Stable self-similar pulses exist with energies much greater than can be tolerated in solitonlike pulse shaping, and this has implications for practical lasers. 相似文献
30.
Bragg gratings in air-silica structured fibers 总被引:1,自引:0,他引:1
We report on grating writing in air-silica structured optical fibers with pure silica cores by use of two-photon absorption at 193 nm. A decrease in propagation loss with irradiation was observed. The characteristic growth curves were obtained. 相似文献