A Gauss-Newton Approach for Nonlinear Optimal Control Problem with Model-Reality Differences

Output measurement for nonlinear optimal control problems is an interesting issue. Because the structure of the real plant is complex, the output channel could give a significant response corresponding to the real plant. In this paper, a least squares scheme, which is based on the Gauss-Newton algorithm, is proposed. The aim is to approximate the output that is measured from the real plant. In doing so, an appropriate output measurement from the model used is suggested. During the computation procedure, the control trajectory is updated iteratively by using the Gauss-Newton recursion scheme. Consequently, the output residual between the original output and the suggested output is minimized. Here, the linear model-based optimal control model is considered, so as the optimal control law is constructed. By feed backing the updated control trajectory into the dynamic system, the iterative solution of the model used could approximate to the correct optimal solution of the original optimal control problem, in spite of model-reality differences. For illustration, current converted and isothermal reaction rector problems are studied and the results are demonstrated. In conclusion, the efficiency of the approach proposed is highly presented.

METHODS FOR IDENTIFYING SUB-REGIONAL MATERIAL PARAMETERS OF CONCRETE DAMS USING MODAL DATA

Methods for identifying sub-regional material parameters of concrete damsusing incomplete rnodal data are presented. With the measurements of the first frequency andincomplete mode shape, identification methods were built by both the output error approach and theminimum deviation approach. The minimum deviation approach was introduced as physical constraints tothe output error approach, allowing the output error-minimum deviation coupled approach to bedeveloped. The simulated annealing-simplex shape algorithm was applied to solve the identificationmodels. Numerical simulations were carried out with noisy incomplete measurements to illustrate therobustness of the methods.

英语弱势学生课堂纠错的效用研究

以Krashen的输入假设和Swain的输出理论为指导,以文山学院两个大学英语新生班为实验对象,研究英语弱势学生课堂纠错的有效方法和策略,并通过对实验数据的比较和分析,提出针对大学英语弱势学生的课堂纠错的重要性、有效性和实用性。

矩阵二阶系统误差反馈调节问题的解

在二阶系统的框架下,考虑了输出与要调节的向量相一致的矩阵二阶系统的输出调节问题,得出了矩阵二阶系统误差反馈调节问题的可解性等价于调节方程MΠS2+DΠS+KΠ=BΓ+P和RΠS+CΠ+Q=0的可解性.通过对调节方程适当的变换,利用求解线性方程组的方法给出了反馈增益矩阵的完全参数化表达,给求解多目标设计问题带来极大便利.数值例子证明了本文的方法简便有效.

误差逐步逼近法在太阳辐射短期预报中的应用

基于武汉市2011年～2012年4个典型月逐时总辐射观测值和中尺度数值天气预报模式（wRF）模拟值。通过以误差逐步逼近方法实现预报效果的提高，即以逐时清晰度指数为因变量，以14个模式输出因子浓缩的4个主分量为自变量，建立清晰度指数MOS预报方程；以预报误差为因变量，分析并遴选预报因子，建立预报方程；重复第二步过程，进一步减少预报误差。结果表明：1）常规MOS方法预报辐射值的年平均绝对百分比误差、相对均方根误差分别为22.1％、27.8％，对常规MOS预报的误差进行2次再预报后，年预报结果的两项误差进一步降至17.4％、22．4％，与常规MOS法相比，预报误差分别下降4.7％、5.4％；2）第一次误差的主要影响因子为清晰度指数，第二次误差的主要影响因子为时角（一天中不同时刻）；3）经过两次误差逐步逼近后，两项误差分别下降3.8％（5月份）～5.4％（8月份）、4.5％（10月份）～6.9％（8月份）。可见，误差逐步逼近法有逐步改善辐射预报效果的作用。