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51.
Qingkai Han·Lina Hao·Hao Zhang·Bangchun Wen School of Mechanical Engineering Automation Northeastern University Shenyang China 《Acta Mechanica Sinica》2010,(3)
This paper addresses a master-slave synchronization strategy for complex dynamic systems based on feedback control.This strategy is applied to 3-DOF planar manipulators in order to obtain synchronization in such complicated as chaotic motions of end-effectors.A chaotic curve is selected from Duffing equation as the trajectory of master end-effector and a piecewise approximation method is proposed to accurately represent this chaotic trajectory of end-effectors.The dynamical equations of master-slave mani... 相似文献
52.
An application to fuzzy economic systems of the fuzzy multi-valued functions theory elaborated by both of us in our previous papers is presented. First, stationary and dynamic fuzzy economic models are defined. Next the optimality of fuzzy trajectories of these models is introduced and investigated. 相似文献
53.
D. Izzo V. M. Becerra D. R. Myatt S. J. Nasuto J. M. Bishop 《Journal of Global Optimization》2007,38(2):283-296
We introduce and describe the Multiple Gravity Assist problem, a global optimisation problem that is of great interest in
the design of spacecraft and their trajectories. We discuss its formalization and we show, in one particular problem instance,
the performance of selected state of the art heuristic global optimisation algorithms. A deterministic search space pruning
algorithm is then developed and its polynomial time and space complexity derived. The algorithm is shown to achieve search
space reductions of greater than six orders of magnitude, thus reducing significantly the complexity of the subsequent optimisation.
This work was partially funded under the Ariadna scheme of the European Space Agency, contract number 18138/04/NL/MV. 相似文献
54.
ZHAO Wei-Qin 《理论物理通讯》2004,42(7)
A revised iterative method based on Green function defined by quadratures along a single trajectory is proposed to solve the low-lying quantum wave function for Schrodinger equation. Specially a new expression of the perturbed energy is obtained, which is much simpler than the traditional one. The method is applied to solve the unharmonic oscillator potential. The revised iteration procedure gives exactly the same result as those based on the single trajectory quadrature method. A comparison of the revised iteration method to the old one is made using the example of Stark effect. The obtained results are consistent to each other after making power expansion. 相似文献
55.
We consider quasistable multicriteria problems of discrete optimization on systems of subsets (trajectory problems). We single
out the class of problems for which new Pareto optima can appear, while other optima for the problems do not disappear when
the coefficients of the objective functions are slightly perturbed (in the Chebyshev metric). For the case of linear criteria
(MINSUM), we obtain a formula for calculating the quasistability radius of the problem.
Translated fromMatemalicheskie Zametki, Vol. 63, No. 1, pp. 21–27, January, 1998.
This research was supported by the Belarus Foundation for Basic Research under grant No. F95-70. 相似文献
56.
57.
等变集压缩场的零点指标公式 总被引:4,自引:0,他引:4
本文在紧致李群作用下的Banach空间中,讨论了等变严格集压缩场的正则零点轨道的指标计算问题,推广了(1),(2)的结果。 相似文献
58.
59.
Bo Li Haichao Zhang Yuxiao Niu Dechao Ran Bing Xiao 《Mathematical Methods in the Applied Sciences》2023,46(1):1096-1110
This paper investigates the problem of trajectory tracking control for quadrotor unmanned aerial vehicle (UAV) in the presence of dynamic obstacles and external disturbance forces/torques. More specifically, two new sliding mode disturbance observers are firstly designed to estimate the external disturbances, in which the observation errors can converge to zero in finite time. Furthermore, utilizing the observation information, a new sliding mode surface-like variable-based position tracking control scheme and a novel nonsingular terminal sliding mode-based attitude synchronization control scheme are developed to drive the UAV tracking the reference trajectory with obstacle avoiding. Moreover, the tracking errors of the close-loop control system can converge to zero within finite time by the analyses of Lyapunov methodology. Finally, the numerical simulation results are presented to illustrate the effectiveness of the proposed control schemes. 相似文献
60.
Haobin Yang Ziyu Wang Zhifeng Tu Junjie Jiang Danlin Xu Zhenwu Mo Haiqi Huang Dongmei Deng 《Annalen der Physik》2023,535(9):2300167
This paper analytically and numerically proposes the propagation dynamics of the symmetric Pearcey Gaussian vortex beam (SPGVB) in the uniformly moving parabolic potential. The optical vortex located in the initial plane produces a vortex channel in the presence of the uniformly moving parabolic potential, called the vortex trajectory. The vortex trajectory can be manipulated dynamically by configuring different combinations of the parameters, and the optical intensity and the focal position can also be affected. Moreover, the spatial dynamic vortex trajectory is derived analytically, and the 2D on-axis and off-axis vortex scenarios are also presented. Our work expands the methods of the vortex trajectory manipulation and may broaden more practical potential applications in the particle manipulation. 相似文献