Best Tracking Performance under Plant Uncertainty and Control Energy Constraint

This paper has investigated best tracking performance for linear feedback control systems in the case that plant uncertainty and control effort need to be considered simultaneously. Firstly, an average integral square criterion of the tracking error and the plant input energy over a class of additive model errors is defined. Then, utilizing spectral factorization to minimize the performance index, we obtain an optimal controller design method, and furthermore study optimal tracking performance under plant uncertainty and control energy constraint. The results can be used to evaluate optimal average tracking performance and control energy in designing practical control systems.     

非高斯型互相关随机数的发生技术

在用蒙特卡罗法进行仿真研究（例如进行测量不确定度评定）时,常常需要发生多个非高斯型互相关的随机数.就这一问题,给出完整的解决方案：用Hermite展开式生成近似的非高斯变量,借助Cholesky分解建立各变量之间的相关性.方法的关键在于对互相关系数矩阵进行“预变形”,使Cholesky分解也适用于非高斯变量.此外,还利用Cholesky分解式下三角矩阵的特点,对矩调整和建立相关性两个过程进行解耦.给出了详细的算法说明.     

What can we learn from the fifties?

Economists have increasingly elicited probabilistic expectations from survey respondents. Subjective probabilistic expectations show great promise to improve the estimation of structural models of decision making under uncertainty. However, a robust finding in these surveys is an inappropriate heap of responses at “50%,” suggesting that some of these responses are uninformative. The way these 50s are treated in the subsequent analysis is of major importance. Taking the 50s at face value will bias any aggregate statistics. Conversely, deleting them is not appropriate if some of these answers do convey some information. Furthermore, the attention of researchers is so focused on this heap of 50s that they do not consider the possibility that other answers may be uninformative as well. This paper proposes to take a fresh look at these questions using a new method based on weak assumptions to identify the informativeness of an answer. Applying the method to probabilistic expectations of equity returns in three waves of the Survey of Economic Expectations in 1999–2001, I find that: (i) at least 65% of the 50s convey no information at all; (ii) it is the answer most often provided among the answers identified as uninformative; (iii) but even if the 50s are a major contributor to noise, they represent at best 70% of the identified uninformative answers. These findings have various implications for survey design.     

关于电子自旋不是一种经典模型

本文通过两种方法证明电子自旋不是一种经典模型。     

基于系统工程的系统分类法及应用

首先叙述了一般文献中对系统的分类，然后对钱学森为首的一批知名学者关于系统的人和了介绍。详细地讨论了Ｓｈｅｎｈａｒ和Ｂｏｎｅｎ对系统的二维分类法，并同钱学森的系统分类法进行联系，根据２－Ｄ分类法，提出了系统开发的三维结构，最后对其应用实例进行了说明。     

高师心理学教学目标的反思与重建

从理论和实际两种角度反思高师心理学教学目标，存在着偏重陈述性知识、机械训练和社会要求，忽视策略性知识、创造性培养和个人需要等弊端，必须重建心理学教学目标框架，突出策略性知识目标、创业素质形成目标和创造能力培养目标，这样才能适应创业教育的要求，寻回心理学应有的价值和地位。     

万州淹没企业实施兼并的程序瑕疵及对策

万州在淹没搬迁企业实施兼并的操作实务中，其程序性法律问题不少。必须正视这一现实，全面审查外来兼并企业的资产信誉状况和兼并主体资格，正确确定被兼并的淹没企业一方的合同主体，准确把握政府及其职能部门或者企业主管机关的角色定位，从程序制度建设上减少兼并合同纠纷，防范兼并欺诈，确保移民补偿资金安全，实现万州经济的可持续发展。     

加入WTO的大学生素质教育

学校推进素质教育的出发点和归宿 ,就是要为培养和造就方方面面的人才服务。中国加入WTO是机遇更是挑战 ,挑战的焦点是培养高素质的国际型人才。结合“入世”面临的现实情况分析 ,笔者对大学生素质教育的重点及具体做法提出了一些个人想法。     

Best tracking performance for integrator and dead time plant

The optimal tracking performance for integrator and dead time plant in the case where plant uncertainty and control energy constraints axe to be considered jointly is inrestigated.Firstly,an average cost function of the tracking error and the plant input energy over a class of stochastic model errors are defined.Then,we obtain an internal model controller design method that minimizes the average performance and further studies optimal tracking performance for integrator and dead time plant in the simultaneous presence of plant uncertainty and control energy constraint.The results can be used to evaluate optimal tracking performance and control energy in practical designs.     

教师素质在中学英语教学创意设计中的作用

教学是一门艺术,艺术需要创造,创造需要灵感,灵感源于积累。英语教学创意设计的目的在于通过精心巧妙地整合、运用各种教学技巧创造性地进行有效教学,以达到最佳教学效果,进而达到提高教学质量和教学水平的目的。