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161.
A new local linear prediction model is proposed to predict chaotic time series in this Letter. We propose that the parameters—the embedding dimension and the time delay of the local linear prediction model—can take values which are different to those of the state space reconstruction in the procedure of finding the nearest neighbor points. We propose a criterion based on prediction power to determine the optimal parameters of the new local linear prediction model. Simulation results show that the new local linear prediction model can effectively predict chaotic time series and the prediction performance of the new local linear prediction model is superior to that of the local linear prediction. 相似文献
162.
A unique method of coupling computational fluid dynamics (CFD) to model predictive control (MPC) for controlling melt temperature in plastic injection molding is presented. The methodology is based on using CFD to generate, via open-loop testing, a temperature and input dependent system model for multi-variable control of a three-heater barrel on an injection molding machine. Results clearly show the benefit of temperature and input dependent system models for MPC control, and that CFD can be used to dramatically reduce the time associated with open-loop testing through physical experiments. 相似文献
163.
本文利用拓扑学方法研究了ω-范畴理论的性质,并对模型个数问题进行了讨论,获得了ω-范畴的新结果,并得到了关于模型个数的几个结果. 相似文献
164.
受有序样本聚类思想的启发,本文针对期权定价模型中的非对称Possion跳———扩散模型,提出了一种基于标的资产价格历史数据的参数估计方法,并得到了较好的结果。 相似文献
165.
在A≈80区奇-奇核旋称反转问题上已提出几种机制,但没有一种理论推断是结论性的.在本工作中将角动量投影壳模型应用到80,82Rb核,对组态为πg9/2⊙νg9/2的正宇称晕带和组态为π(p1/2,p3/2,f5/2)⊙νg9/2 的负宇称晕带理论计算和实验结果进行了比较,特别是对正宇称晕带中的signature反转机制进行了探讨.角动量投影壳模型计算显示正宇称晕带中的signature反转是原子核随自旋增加形状发生变化的信号,其间原子核从低自旋的长椭球变到高自旋的扁椭球.此外,还确定了此两带的原子核形状 相似文献
166.
167.
Hiroaki Koga Takeyuki Arai Taisuke Hamada Shigeyoshi Sakaki 《Journal of molecular catalysis. A, Chemical》2003,200(1-2):223-228
In the two-electron reduction of diphenylsulfoxide to diphenylsulfide, which is considered a model reaction of sulfite reduction catalyzed by sulfite reductase, methylviologen-pendent iron(III) porphyrin exhibits much higher catalytic activity than usual iron(III) and manganese(III) tetraphenylporphyrins, while cobalt(II) tetraphenylporphyrin exhibits much less catalytic activity than the others. Discussion about the active species and the reason of the acceleration by methylviologen-pendent is presented. 相似文献
168.
O. T. Bruhns N. K. Gupta A. T. M. Meyers H. Xiao 《Archive of Applied Mechanics (Ingenieur Archiv)》2003,72(10):759-778
Summary We propose an exact analysis for finite bending of a compressible elastoplastic strip with combined hardening at a given
stretch normal to the bending plane. We apply the self-consistent eulerian rate-type elastoplastic model based on the logarithmic
rate, in conjunction with a Tresca-type loading function. Utilizing the maximum circumferential stretch at the outer surface
as an independent parameter, we derive exact analytic expressions for the bending angle, the bending moment, the outer and
inner radii, the radii of the two elastic-plastic interfaces and the circumferential stretches at these two interfaces, as
well as the stress distributions in every current cross section. In particular, we establish an explicit relation between
the two circumferential stretches at the two elastic-plastic interfaces, and we show that this relation is universal for all
cases of hardening. We show also that the maximum and minimum circumferential stretches at the outer and inner surfaces obey
a reciprocal relation in the course of both elastic and elastic-plastic deformations.
Received 4 June 2002; accepted for publication 14 November 2002
This research was carried out under financial support from the German Science Foundation (DFG) (Contract No.: Br. 580/26-2)
and from Alexander von Humboldt Foundation. We wish to express our sincere gratitude to these Foundations. 相似文献
169.
崔文善,闫培生,张金政.木耳高产栽培配方的数学模型及优化研究.数理统计与管理,1997,16(4),8~11.本文采用回归正交设计方法,研究了泡桐木屑栽培木耳的配方组合与产量之间关系,并建立了数学模型。结果表明,以泡桐木屑为主料,各组分的适宜用量,以及它们之间合理组合,可显著提高木耳产量,降低生产成本,并具有较好的稳定性;其配方的优化方案为:泡桐木屑77.6~80.2%,麦夫12.5~14.8%,石灰2.4~2.7%,MgSO41.3%,KH2PO42.6%,糖1.0%。 相似文献
170.
Georgios M. Kontogeorgis Iakovos V. Yakoumis Philippos Coutsikos Dimitrios P. Tassios 《Fluid Phase Equilibria》1997,140(1-2):145-156
Using an extensive database of experimental critical properties for heavy compounds, which have been compiled mostly from recent literature sources, it is shown that the ratio Tc: Pc (critical temperature over critical pressure) can be expressed in terms of the van der Waals surface area (Qw), which is readily available for any compound from the group contributions of Bondi (given also in UNIFAC tables). The proposed correlation is based on the hole theory of Kurata and Isida for n-paraffin liquids, which is mathematically equivalent to Flory's theory of polymer solutions. The method is suitable for medium to high molecular weight compounds with unknown critical constants. For example, if only one of the two critical constants is available, then the proposed generalized equation offers a useful rapid procedure for the estimation of the other critical property for use in corresponding states, and other relevant applications where knowledge of the critical properties is required. Furthermore, the Tc: Pc method can be used in many cases for identifying the most suitable among the existing group contribution methods for estimating the critical properties of heavy and complex compounds for which experimental values are, very often, not available. 相似文献