Incremental Feature Selection

Feature selection is a problem of finding relevant features. When the number of features of a dataset is large and its number of patterns is huge, an effective method of feature selection can help in dimensionality reduction. An incremental probabilistic algorithm is designed and implemented as an alternative to the exhaustive and heuristic approaches. Theoretical analysis is given to support the idea of the probabilistic algorithm in finding an optimal or near-optimal subset of features. Experimental results suggest that (1) the probabilistic algorithm is effective in obtaining optimal/suboptimal feature subsets; (2) its incremental version expedites feature selection further when the number of patterns is large and can scale up without sacrificing the quality of selected features.     

Analysis,simulation and verification of a bipolar current source power resonant inverter

A high‐frequency bipolar current source resonant inverter introduced in this paper has dramatic zero‐voltage‐switching (ZVS) characteristic. The analytic expressions of the resonant voltage and current are given. It indicates that the resonant waveform is composed of two parts, i.e. the oscillatory component and the stationary component. In special cases, the resonant waveform degenerates into the mono‐frequency component, as presents the graceful sinusoidal wave with very low total harmonic distortion (THD) value. Based on the closed‐form voltage and current, the component stresses on reactive elements are obtained. The impact of different component values and operating frequencies on ZVS feature is also discussed. It should be noted that the ZVS merit may be lost if the components are carelessly selected. The validity of the theoretical analysis has been proven with Pspice simulations and experimental results. Copyright © 2004 John Wiley Sons, Ltd.     

电子冷冻加工的特点与应用研究

针对采用热电制冷的冷冻加工方式的特点与应用进行了研究,对于特殊工件的加工提出了一种全新的加工方式,它改革了传统的工件夹持方法,为超小、超薄、异形、低强度脆性材料的工件的加工提供了一种可能,同时电子冷冻加工使低温加工成为现实,可解决一般常用材料及某些特殊材料的加工问题,特别适宜于薄片件,韧、粘性材料的加工,结构简单,温度可调,成本低,无粉尘和气味,可应用于各行各业的机械加工中.     

西门子S7-300PLC在胎面联动线控制系统中的应用

本文介绍了SIEMENS公司S7—300PLC在胎面联动生产线控制系统中的应用。对联动线的工艺流程、系统构成、控制方案、程序设计作了比较详细的说明，并且还介绍了PROFIBUS现场总线在本联动生产线中的应用。     

A New Immune Genetic Algorithm and Its Application in Redundant Manipulator Path Planning

In this paper, first the immune system is analyzed in a relatively deeper and all‐sided point of view reflecting the fresh research in biology. Second, based on the previous statements, a new optimization method, the immune genetic algorithm (IGA), is presented by simulating the behavior of the biological immune system and is proved to converge to the global optimum with probability 1. Third, a new method on the multi‐object optimization that is transformed into a single‐object one is proposed based on the joints' best compliance in the redundant robot path planning using IGA. Last, the experiment results show that the method of this article behaves more successfully. © 2004 Wiley Periodicals, Inc.     

硫酸高铈与对二甲苯反应的动力学研究

本工作测定了不同温度下硫酸高铈与对二甲苯反应的速率常数及表观活化能Ｅａ＝ １１１．５ｋＪ·ｍ ｏｌ－ １。在动力学测定的的基础上确定了此反应的速率方程为ｄ［ＰＴＡＬ］／ｄｔ＝ ｋ［ＰＸ］［Ｃｅ（ＩＶ）］     

消失模铸造铸铁件水基涂料的研制

选用石英粉为耐火骨料，酸式磷酸盐为粘结剂，通过正交试验确定了铸铁件消失模水基涂料的最佳配比。经测试和生产验证，其性能良好，能很好地适应生产要求。     

高血压形成与发展的血流动力学分析

根据作者提出的血流动力学参数计算公式,研究了不同年令和不同血压下血流动力学参数的变化从中得出外周阻力的增高是高血压最主要的危险因素。并经理论分析和临床实测证实了这个结论。     

[(t-BuCP)_2NdMe]_2/添加剂体系催化丙烯腈聚合

本文研究了［（t－BuCP）2NdMe］2／添加剂体系对丙烯腈的催化聚合,并考察了添加剂比例、温度、催化剂用量、单体浓度及溶剂对聚合活性的影响．