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81.
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83.
D. A. Gubaidullin R. G. Zaripov R. G. Galiullin E. R. Galiullina L. A. Tkachenko 《High Temperature》2004,42(5):794-802
Nonlinear oscillation of aerosol in the vicinity of a resonance frequency that is twice lower than the first eigenfrequency (subharmonic resonance) is experimentally investigated in tubes with different conditions at the ends. The time dependence of the number density of aerosol droplets is determined, and the effect of the frequency and intensity of oscillation on the process of coagulation of droplets is studied. The nonmonotonic pattern of the dependence of the time of coagulation of aerosol droplets on the frequency of excitation with a minimal value at resonance is found. Ordered space-time structures (alternation of denser and looser regions of aerosol) are revealed in the visible region in the vicinity of the middle of a closed tube. 相似文献
84.
对称非线性系统的无交互控制 总被引:1,自引:0,他引:1
本文讨论了具有对称性的非线性系统的无交互控制问题。通过定义对称系统的导出分布族的新概念,我们得出了问题可解的条件。我们取得的结果较不具对称性的情况要简单一些。从而说明,对称性不仅使得系统具有较好的结构,而且使得它的其它一些问题的研究得到简化。 相似文献
85.
E. I. Mashinskii 《Journal of Mining Science》2003,39(1):8-14
Using the theory of microplasticity as the base, it is shown that the curvature of graph for the function describing the equation of state of rocks can change its sign depending on the value of the mechanical energy applied. The experiments on dolomites under the strains of order of 10-6 reveal an increase in wave velocities as the amplitude grows. 相似文献
86.
LIU Xiao-wen LI Na PAN Chun-de 《中国矿业大学学报(英文版)》2005,15(4):344-347
An embedded protective device for 35kV power line is worked out based on Philips' LPC2292 ARM MCU. Several aspects such as embedded design technique adopted in the system framework, application of adaptive theory in data acquisition, Board Support Packet (BSP) developing and task dispatching related to operating system are discussed. Both hardware and software framework of the system are given. Advanced hardware platform and software development environment is applied in design of the system, with the advanced co-design technology. 相似文献
87.
After considering the stabilization of a specific class of stochastic nonlinear systems in a companion paper, in this second part, we address the classical question of when is a stabilizing (in probability) controller optimal and show that for every system with a stochastic control Lyapunov function it is possible to construct a controller which is optimal with respect to a meaningful cost functional. Then we return to the problem from Part I and design an optimal backstepping controller whose cost functional includes penalty on control effort and which has an infinite gain margin. 相似文献
88.
89.
A remarkable nonlinearity has been observed for electric transport in K-TCNQ (potassium tetracyanoquinodimethane) quasi-one-dimensional
conductor. The negative differential resistance region appears afterV
m (turn over voltage), beyond which voltage goes down with increase of current. A possible mechanism is discussed in terms
of dynamics of charged solitons and domain walls in one-dimensional molecular stacks of these types of crystals. 相似文献
90.
G. Bartolini A. Ferrara 《International Journal of Adaptive Control and Signal Processing》1992,6(3):237-246
In this paper we pursue a twofold aim. First we want to simplify the complexity of the classical Monopoli's scheme, the so-called ‘Augmented error signal control scheme’. Then we also wish to cope with the realistic situation in which the presence of unmodelled dynamics has to be taken into account. This latter problem has been faced in the literature by suitably modifying the adaptation mechanism in order to avoid undesired phenomena as well as to obtain an attractive stability region for the state trajectories starting from any point in a predefined initial condition set. In our case the necessity of introducing any sort of modification in the adaptation mechanism is completely avoided, but we still obtain asymptotic stability of the output error signal. 相似文献