FUZZY概率法在地下水环境质量评价中的应用

概要叙述了FUZZY概率法的原理及其在环境质量评价中的应用方法,就阜新新邱露天煤矿排土场淋溶水对附近于家沟地区地下水环境质量的影响进行了评价研究。采用FUZZY概率法对影响区地下水质量进行了评价,确定出该区域地下水环境质量等级,为于家沟地区地下水的污染治理工作提供了可靠的科学依据。     

一种智能控制算法在智能仪器中的实现

数字PID控制以其算法简单、实用性强而广泛应用于智能仪器控制中，但由于控制系统的非线性和复杂性使得PID的控制精度和鲁棒性较差。这里介绍了一种适用于智能仪器控制中的智能控制算法，它结合了人工智能中的专家系统技术、模糊控制技术及常规的PID控制方法，具有简单、实用性强、控制精度高和鲁棒性好的特点。     

基于变权法的多因素FUZZY决策模型在工程评标中的应用

针对基于变权法的多因素FUZZY决策模型与工程评标的程序、特点,将变权法理论及模糊理论应用于工程评标,建立相应的模糊决策方法,进行定量分析和综合比较,使决策结果更加科学、可靠。     

Application of fuzzy PID self-adaptive controller in pressurisation control system of counter gravity casting

Abstract

Good counter gravity casting process control is very important to the production of high quality light metal parts. However, due to uncertain dynamic properties, large delay and interactive influencing factors, this kind of process control is quite complex and it is hard to build a precise mathematic model to describe its characteristics. PID control dose not depend on mathematic model, but once the parameters are given, it cannot regulate itself and cannot get satisfied control effect. In order to satisfy the higher control performance requirement, fuzzy logic control is introduced, which is used to revise three coefficients of PID controller. It can greatly overcome the defects of conventional parameter fixed PID algorithm and get a good self-adaptive ability. Compared with the commonly used classical PID controller, the proposed fuzzy PID controller shows excellent robustness against system parameter variations and external disturbances in the counter gravity casting machine.     

Numerical analysis of factors influencing Charpy impact properties of TMCR structural steels using fuzzy modelling

Abstract

The influence of chemical composition and thermomechanical processing parameters on the Charpy impact energy of grade 420/460 TMCR (thermomechanically controlled rolled) steels was investigated using fuzzy modelling technology. Fuzzy modelling was applied to develop generic models for the prediction of Charpy impact properties. The fuzzy models obtained, which involved chemical compositions, processing conditions, and Charpy impact energy, were used to reveal correlations between individual influence factors and Charpy impact toughness. Numeric analysis shows that low carbon equivalent value (CEV), low sulphur residual, and low processing temperature are all beneficial to impact toughness, predictions which fit with known metallurgical knowledge thus demonstrating the integrity of the model.     

模糊控制理论在磨矿分级过程自动控制中的应用

模糊控制在生产和生活中得到广泛的应用,其被控对象可以是确定或模糊的、单变量或多变量的、有滞后或无滞后的,定常的或时变的,以及具有耦合和干扰等多种情况.对于那些难以建立精确的数学模型的复杂对象,更适宜采用模糊控制.实践证明,模糊控制对解决磨矿分级系统的自动控制取得了良好的控制效果.     

Fuzzy-differential evolution algorithm for planning time-optimal trajectories of a unicycle mobile robot on a predefined path

An evolutionary technique with a Fuzzy Inference System (FIS) is offered for planning time-optimal trajectories on a predefined Visibility Graph Method Dijkstra (VGM-D) path of a Nomad 200 mobile robot (MR). First of all, the segmented trajectory is generated by the VGM-D algorithm. Line and curve segments are the components of the trajectory. The number of intersections of the segmented VGM-D path determines the curve segments number. It is assumed that, at each curve segment, translation velocity v _t is taken as constant. The Differential Evolution (DE) algorithm finds v _t values of all the curve segments, which minimize the trajectory tracking time. Line segments lengths are used to calculate the constraints of the problem according to the Nomad 200's limitations on the translation velocity and acceleration/deceleration. The structures of the curve segments are modeled by FIS to decrease the DE's execution time. Another FIS model is used to define the upper bound of the translation velocities on the curve segments for the same purpose. Both FIS models are trained by the adapted-network-based fuzzy inference system (ANFIS). Experiments are successfully implemented on the Nomad 200 MR.     

炼油厂常压塔侧线质量实时监测模糊专家系统

通过对炼油厂分馏塔侧线质量进行机理分析，并根据实际流程利用ＡＳＰＥＮ对过程进行模拟得到各控制变量与侧线质量的对应结果，利用数据统计方法，得到带有可信度ＣＦ量度的规则。利用正向推理，构置了一个基于规则在线监测炼油厂分馏塔侧线质量指标的模糊专家系统ＳＱＰＥＳ，并利用工厂采集的实时数据对所建立的专家系统进行了验证。结果表明，这种规则获取手段对建立炼油厂分馏塔质量指标监测的专家系统是适用的，它的建立，即可     

一种自学习模糊智能控制器

本文从智能控制行为的特征变量出发,找出动态过程的特征信息,从而得到产生式规则来构成模糊控制器的自学习算法规则集,最后给出数字仿真的实例。     

基于模糊推理的NURBS曲线直接插补进给速度确定方法

为了提高复杂自由曲线数控加工的效率和精度,采用NURBS曲线拟合加工曲线,建立其曲率半径计算数学模型,针对自由曲线曲率半径变化范围大的特点,提出一种冗余误差控制NURBS曲线插补算法与模糊推理运算相结合的进给速度确定新方法.经MATLAB环境下进给速度插补过程仿真,并与冗余误差控制进给速度插补算法、弓高误差控制自动调节速度插补算法比较,结果表明:该方法可根据自由曲线的曲率半径及其变化率值经模糊推理方法确定出合适的进给速度以提高加工效率,并能使弓高误差不超出最大允许值以保证加工插补精度.