δ－Al_2O_3纤维／Al－12Si复合材料室温拉伸强度分析

对δ－Ａｌ２Ｏ３纤维／Ａｌ－１２Ｓｉ复合材料室温拉伸强度的分析表明，在实验条件下该复合材料存在δ－Ａｌ２Ｏ３纤维的最小体积分数Ｖｍｉｎ和临界体积分数Ｖｃｒｉｔ，并求出其基体强度σ＇ｍ和室温强度σｃ－δ－Ａｌ２Ｏ３纤维体积分数Ｖｆ直线方程及纤维的临界长度ｌｃ和复合材料的剪切应力τｉ．确定复合材料的ＲＯＭ预测曲线，应首先判断σ＇ｍ是否等于未增强合金的强度σｕｍ才能得出正确的结论     

非饱和土的抗剪强度理论研究

从孔隙水的存在状态出发 ,围绕Bishop抗剪强度公式中存在的几个疑点展开讨论 .认为非饱和土中支配强度和变形的应力之所以不同 ,是因为非饱和土中存在一种性质与有效应力不同的应力———内部应力 ,它不传递 ,仅影响土的塑性变形 .同时还对Bishop ,Fredlund和卢肇钧提出的抗剪强度公式中的参数测试方法进行分析 ,指出 :各种抗剪强度理论在概念上都是相同的 ,其区别仅在于确定由吸力产生的那部分有效应力时采用的参数和测试方法不同     

Kinetics of two-step anionic polymerization

This article deals with the kinetics of two-step anionic polymerization by way of a non-steady state method. Several molecular parameters can be evaluated using the formulae developed. A bimodal molecular weight distribution function for the resulting polymer is derived from the set of kinetic differential equations, which is in agreement with the experimental data reported.     

控制理论的现状及对它的期望

本文首先简述了控制理论的发展过程，侧重叙述促进现代控制理论发展的主要因素，然后叙述了控制理论主要研究方向的进展及有待解决的问题，最后从第十二届ＩＦＡＣ世界大会看人们如何对待控制理论的各个方面。     

基于信息的智能控制理论研究

本文介绍的基于信息的智能控制理论的发展过程，主要分为智能控制的信息指标和智能控制的信息结构分析两部分，文中在最后对这套理论可能的发展方向进行了探讨。     

Quantitative feedback theory with applications in welding

Two different control systems were developed using quantitative feedback theory for weld quality improvement. The first application to be discussed was designed for the resistance pinch welding process and uses electrode displacement and force as feedback parameters. A correlation between weld quality and electrode displacement is established for constant electrode force. The system is capable of producing repeatable welds of consistent quality, with wide variations in weld parameters. This is the first time feedback control has been successfully applied to pinch welding. The second example presented in this paper was developed for penetration control of the gas-tungsten-arc welding process. The feedback signal is obtained by measuring the amount of light emitted from the back side of the weld. Welds of constant penetration have been demonstrated in tests with travel speeds varying from 1.5 to 6 inches per minute and with 200 per cent changes in part thickness.     

Design of minimax robust LQG controllers under parameter and noise uncertainties

The problem of design of minimax robust LQG controllers for linear systems with parameter and noise uncertainties is considered in this paper. Necessary and sufficient conditions for converting this problem to a two-person, zero-sum continuous game problem are presented. A simple procedure for design of a suboptimal minimax robust LQG controller, i.e., the LQG controller for least-favourable model, is proposed. Necessary and sufficient conditions for the existence of a saddle point are established. Under these conditions, the controller obtained is exactly the minimax LQG controller. When there does not exist a saddle point, the worst-case error between the controller obtained and the minimax robust LQG controllers under described uncertainties is bounded.     

Fastmet工艺评述

介绍了Ｆａｓｔｍｅｔ工艺及发展状况，并对工艺特点和指标进行了分析。使用冷固结含碳球团和转底炉使该工艺可直接采用粉矿和提高生产效率，但因硫含量高、铁品位低而产品质量较差。不过投资和生产成本与传统工艺比较却占有较大优势。     

A Topological Implementation for Motion Planning of a Robotic Arm

An efficient path planning algorithm based on topologic method is presented in this paper.The collision free path planning for three-joint robotic arm consists of three parts:partition of C-space,construction of CN and search for a path in CN.We mainly solved the problems of partitioning the C-space and undging the connectivity between connected blocks,etc.For the motion planning of a robotic arm with a gripper,we developed the concepts of global planning and local planning,and discussed the basic factors for constructing the planning system.In the paper,some evaluation and analysis of the complexity and reliability of the algorithm are given,together with some ideas to improve the efficiency and increase the reliability.At last,some experimental results are pesented to show the efficency and accuracy of the algorithm.     

不等波纹函数低通原型的理论及应用

本文提出不等波纹函数低通原型，并对其理论进行初步探讨。切比雪夫函数及最平坦型巴特活兹函数皆为其特例。文中给出不等波纹函数的几个性质，最后给出两个应用实例，消除耦合环自感部分的影响；抑制高次模的微带圆盘腔带通滤波器。