两自由度闭链机器人的神经网络自适应控制

A closed-chain robot has several advantages over an open-chain robot, such as high mechanical rigidity, high payload, high precision. Accurate trajectory control of a robot is essential in practical use. This paper presents an adaptive proportional integral differential (PID) control algorithm based on radial basis function (RBF) neural network for trajectory tracking of a two-degree-of-freedom (2-DOF) closed-chain robot. In this scheme, an RBF neural network is used to approximate the unknown nonlinear dynamics of the robot, at the same time, the PID parameters can be adjusted online and the high precision can be obtained. Simulation results show that the control algorithm accurately tracks a 2-DOF closed-chain robot trajectories. The results also indicate that the system robustness and tracking performance are superior to the classic PID method.     

易经的和谐思想体系

易经和谐思想发韧于天文学,立竿测影,观天测地,窥视天地人和谐一体的隐秘。以象数语言规则体系建立数学模型,捕捉阴遇阳与阳遇阴(生)吉、阳遇阳阴遇阴(克)凶的宇宙人世生存生克制化大道变化之神。易经和谐思想是自然神化的天人合一天人感应心物同一的宇宙观,世界的物质客观实在的本质——性,性是看不见摸不着的阴阳之性——"真无,"从而阴阳相遇,从无生有,创生大千世界。万物一体,天人感应,以心体悟象蕴,探索世界万物阴阳协调、刚柔相济则吉,反之则凶的科学奥妙。     

以科学发展观为指导切实加强高校纪检监察工作

结合多年来保山师专纪委开展纪检监察工作的实践,针对近期中央制定的《建立健全惩治和预防腐败体系2008-2012年工作规划》的精神,提出了在新形势下切实加强高校纪检监察工作的措施与任务,论述了新形势下加强反腐倡廉工作的重要性。     

例谈直觉思维与数学解题

数学教学是数学思维活动的教学,直觉思维在数学思维活动中有着特殊的地位和作用。文章通过对直觉猜想、直觉洞察、直觉类比、数形结合、直觉归纳和审美直觉这六个方面举例论证直觉思维在数学解题活动中的作用。同时也分析了运用直觉思维解题需要注意的问题,并介绍了调控这些问题所必需掌握的知识,如数学观念、学习本质以及逻辑思维与直觉思维的互补作用。     

关于一分段函数求二阶导数的讨论

本文指出了文献中一分段函数求分界点处二阶导数的不足之处,并且给出了正确解决此问题的三种方法:导数定义法、含参量正常积分可微性定理法、导数极限定理法。     

强迫时滞Duffing方程概周期解的存在性

该文结合运用不动点定理研究一类含时滞强迫Duffing方程概周期解的存在性,推广了已有的结果。     

Multi-Objective Optimization of Water-Sedimentation-Power in Reservoir Based on Pareto-Optimal Solution

A multi-objective optimal operation model of water-sedimentation-power in reservoir is established with power-generation, sedimentation and water storage taken into account. Moreover, the inertia weight self-adjusting mechanism and Pareto-optimal archive are introduced into the particle swarm optimization and an improved multi-objective particle swarm optimization (IMOPSO) is proposed. The IMOPSO is employed to solve the optimal model and obtain the Pareto-optimal front. The multi-objective optimal operation of Wanjiazhai Reservoir during the spring breakup was investigated with three typical flood hydrographs. The results show that the former method is able to obtain the Pareto-optimal front with a uniform distribution property. Different regions (A, B, C) of the Pareto-optimal front correspond to the optimized schemes in terms of the objectives of sediment deposition, sediment deposition and power generation, and power generation, respectively. The level hydrographs and outflow hydrographs show the operation of the reservoir in details. Compared with the non-dominated sorting genetic algorithm-II (NSGA-II), IMOPSO has close global optimization capability and is suitable for multi-objective optimization problems. LI Hui, born in 1981, male, doctorate student. Supported by National Science Fund for Distinguished Young Scholars (No.50725929) and National Natural Science Foundation of China (No.50539060,50679052).     

中国传统思维方式的若干特点及变革取向

中国传统思维方式从大的方面看表现为注重一体性、体悟性、政治功利性等不同特点.在这个大框架下,对立统一性、模糊性、意象性、注重内因性、唯神唯圣性、趋同性、唯上性、经验性等特征又程度不同地表现在传统的思维方式中.这种思维方式虽然有不少积极而有价值的内容,但是也有许多落后的东西.变革落后的思维方式是一项长期性的、意义极其深远的工作.变革的途径是:一方面要积极吸收西方先进的思维方式,特别是要注重学习西方的分析思维方式;另一方面也要继承和发扬中国传统思维方式中那些正确、积极、合理的东西.     

含参量非正常积分的局部一致收敛

引入了含参量非正常积分局部一致收敛的定义,利用此定义证明了局部一致收敛与含参量非正常积分连续的等价性．最后讨论了含参量非正常积分一致收敛、局部一致收敛与收敛的关系,它们依次蕴含但其逆均不成立．     

用Lyapunov—Schmidt方法求一类方程的近似解

使用Lyapunov—Schmidt方法求出给定方程的分歧方程,解决了方程初值难取定与奇异性的问题．Newton迭代得到其在分歧点附近的近似非平凡解枝。