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991.
992.
Function approximation-based sliding mode adaptive control 总被引:1,自引:0,他引:1
For the position tracking in DC motor with unknown bound time-varying dead zone uncertainties, a novel sliding mode adaptive
controller is proposed by means of sliding mode and function approximation technique in this paper. First, control law with
an uncertain term and another compensative term is obtained using sliding mode technique, and then the function approximation
technique is employed to transform the uncertain term into finite combinations of orthonormal basis functions. The concrete
expressions of uncertain term and compensative term can thus be derived based on the Lyapunov design. Actual system control
experiments of the sliding adaptive control proposed are given. 相似文献
993.
孔周弹塑性变形与疲劳循环次数的相关性 总被引:2,自引:1,他引:1
应用白光散斑相关技术研究了孔周弹塑性变形与疲劳循环次数的相关性,以便探索疲劳寿命的预测方法.疲劳实验在单边带缺口的拉伸板状试件上进行,试件由GH4169材料制成,试件表面上喷涂了白光散斑图.疲劳加载采用0→Pmax→0的循环加载方式,加载波形为正弦波,加载频率为10Hz.实验中,按一定的疲劳循环周次在零载及最大载荷两种状态下停机、采图.应用数字图像相关技术求出孔周附近的残余位移场,并应用逐点最小二乘法求出应变场.实验中获得了一些对于疲劳寿命研究很有意义的结果. 相似文献
994.
995.
MENG Xiang-Guo WANG Ji-Suo LIANG Bao-Long 《理论物理通讯》2008,49(6):1457-1460
In this paper, in terms of the technique of integration within an ordered product (IWOP) of operators and the properties of the inverses of q-deformed annihilation and creation operators, normalizable q-analogue of the squeezed one-photon state, which is quite different from one introduced by Song and Fan [Int. 3. Theor. Phys. 41 (2002) 695], is constructed. Moreover, the Wigner function and phase probability distribution of q-analogue of the squeezed one-photon state are examined. 相似文献
996.
We propose two physical schemes, which can teleport unknown atomic entangled states from user A (Alice) to user B (Bob) via GHZ class states as quantum channel The two schemes are both based on cavity QED techniques. In the two schemes, teleportation and distillation procedures can be realized simultaneously. The second teleportation scheme is more advantageous than the first one. 相似文献
997.
SHAO Yu-Chong FAN Hong-Yi 《理论物理通讯》2008,49(4):866-870
For Hermite polynomials of radial coordinate operator in three-dimensional coordinate space we derive its normal ordering expansion, which are new operator identities. This is done by virtue of the technique of integration within an ordered product of operators. Application of the new formulas is briefly discussed. 相似文献
998.
HAO Hong-Hai WANG Guang-Sheng ZHANG Da-Jun 《理论物理通讯》2009,51(6):989-999
Two non-isospectral KdV equations with self-consistent sources are derived. Gauge transformation between the first non-isospectral KdV equation with self-consistent sources (corresponding to λt = -2aA) and its isospectral counterpart is given, from which exact solutions for the first non-isospectral KdV equation with self-consistent sources is easily listed. Besides, the soliton solutions for the two equations are obtained by means of Hirota's method and Wronskian technique, respectively. Meanwhile, the dynamical properties for these solutions are investigated. 相似文献
999.
Based on the Husimi operator in pure state form introduced by Fan et al., which is a squeezed coherent state projector, and the technique ofintegration within an ordered product (IWOP) of operators, as well as theentangled state representations, we obtain the Husimi functions of theexcited squeezed vacuum states (ESVS) and two marginal distributions of theHusimi functions of the ESVS. 相似文献
1000.