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91.
Z.-M. GET.-N. LIN 《Journal of sound and vibration》2002,251(3):519-542
The dynamic behavior of a gyrostat system subjected to external disturbance is studied in this paper. By applying numerical results, phase diagrams, power spectrum, period-T maps, and Lyapunov exponents are presented to observe periodic and choatic motions. The effect of the parameters changed in the system can be found in the bifurcation and parametric diagrams. For global analysis, the basins of attraction of each attractor of the system are located by employing the modified interpolated cell mapping (MICM) method. Several methods, the delayed feedback control, the addition of constant torque, the addition of periodic force, the addition of periodic impulse torque, injection of dither signal control, adaptive control algorithm (ACA) control and bang-bang control are used to control chaos effectively. Finally, synchronization of chaos in the gyrostat system is studied. 相似文献
92.
用光学多通道分析仪系统作高分辨光谱测量的技术 总被引:1,自引:0,他引:1
通常的光多通道分析仪(OMA)存在着同时谱宽与分辨率的矛盾.本文所述方法,在不减小谱宽的前提下,可将该分析仪光谱分辨率提高1~2量级,使之可适用于高分辨率谱研究. 相似文献
93.
塞曼石墨炉原子吸收光谱法测定粉尘降尘中痕量锡 总被引:5,自引:0,他引:5
以KOH熔样,又以KOH作基体改进剂,研究了测定锡的灰化温度、原子化行为和消除干扰及试样前处理的方法,以KOH熔解的粉尘及降尘样液,特别适用于塞曼石墨炉的测定,背景可完全扣除。方法简便、快速、准确,灵敏度和精度高。相对标准偏差为4.0%,回收牢在96.4~110%范围内。 相似文献
94.
95.
在(NH4)3VS4/CuI/Py反应体系中合成了新化合物 [VS4Cu6(Py)8I3]并测定其晶体结构。该化合物(C40H40N8Cu6I3S4V)属正交晶系, 空间群为Fdd2, 晶胞参数为: a = 29.924(6), b = 13.475(3), c = 25.853(5) , V = 10425(4) ?, Dc = 2.006 g/cm3, Mr = 1573.92, Z = 8, (MoK) = 4.546 mm-1, F(000) = 6048。结构由直接法解出, 用全矩阵最小二乘法修正, 最终偏离因子R = 0.023, wR = 0.069。簇合物分子是由6个带端基配体的Cu沿着四面体单元VS4的6条SS边配位而成, 6个Cu排列成了1个八面体, V基本位于八面体的中心, 整个分子具有C2对称性。 相似文献
96.
97.
We analyze the critical length for design purposes of six-dimensional spaces invariant under translations and reflections
containing the functions 1, cos t and sin t. These spaces also contain the first degree polynomials as well as trigonometric and/or hyperbolic functions. We identify
the spaces whose critical length for design purposes is greater than 2π and find its maximum 4π. By a change of variables,
two biparametric families of spaces arise. We call shape preservation region to the set of admissible parameters in order
that the space has shape preserving representations for curves. We describe the shape preserving regions for both families.
To our friend Mariano Gasca on occasion of his 60th birthday
Research partially supported by the Spanish Research Grant MTM2006-03388, by Gobierno de Aragón and Fondo Social Europeo. 相似文献
98.
有限混合Gamma分布的拓扑稠密性证明 总被引:2,自引:0,他引:2
首先给出了有限混合Erlang分布在正实数轴上所有概率分布中稠密的理论证明,进而给出了混合Gamma分布具有稠密性的结论,说明有限混合Gamma分布具有广泛的适用性,可以用来刻画正实数轴上的任意随机变量. 相似文献
99.
Inmaculada García Cuesta José Sánchez-Marín Alfredo M J Sánchez de Merás 《Chemphyschem》2006,7(2):508-513
Investigations into the charge-separated states and electron-transfer transitions in tetracyanoethylene (TCNE) complexes have recently generated much interest. In this work we present theoretical calculations showing that the most stable structure of the dianion TCNE2- has D2d symmetry in vacuum as well as in the solvents dichloromethane and acetonitrile. By means of the coupled cluster linear response, we compute the vertical electronic spectrum in both the gas phase and solution. The theoretical results are compared to the experimental data and good agreement is achieved. 相似文献
100.
It is shown that the presence of mixed-culture growth in batch fermentation processes can be very accurately inferred from total biomass data by means of the wavelet analysis for singularity detection. This is accomplished by considering simple phenomenological models for the mixed growth and the more complicated case of mixed growth on a mixture of substrates. The main quantity provided by the wavelet analysis is the Hölder exponent of the singularity that we determine for our illustrative examples. The numerical results point to the possibility that Hölder exponents can be used to characterize the nature of the mixed-culture growth in batch fermentation processes with potential industrial applications. Moreover, the analysis of the same data affected by the common additive Gaussian noise still lead to the wavelet detection of the singularities although the Hölder exponent is no longer a useful parameter. 相似文献