Discussion on Some Problems of ExpertSystem for Rock Mass Classification

On the basis of discussing present situation for classification of rock masses and necessity of building expert system of rock masses.The intelligent design software for classification of rock masses CRES has been completed. In this paper the CRES is expounded systematically in the following,such as knowledge_base,data_base,reasoning machine,learning machine,and so on.Finally,the CRES is used for verifying 30 engineering examples and is used to classify rock masses of two roadways successfully .The CRES has been connected to SBSDES.     

基于支持向量机的蘑菇毒性判别研究

毒蘑菇和可食用蘑菇在外表上非常相似,依靠传统方法难以判别。为了实现判别上的自动化和增强可靠性,提出了一种基于支持向量机的蘑菇毒性判别方法。首先给出了数据样本和数据预处理的方法,其次建立C-SVM模型并进行训练,同时依照一对一方法实现了支持向量机的多分类,最后使用定步长探索法获得了模型的最优参数。仿真实验对比分析了不同样本量,不同参数下所提方法的准确度,验证了该方法在蘑菇毒性判别上的可行性。同时,使用神经网络、决策树方法进行分类器间的性能对比,发现与神经网络、决策树的判别结果相比,所提方法具有准确率高、操作方便、实用性强等优点。     

基于EFAST的盾构隧道安全指标全局敏感性分析

为了分析地铁隧道健康监测中各个指标之间的相互演化作用关系,提出了一种对监测数据进行分析的数据挖掘思路,将傅里叶幅值灵敏度检验扩展法（EFAST）应用于各项指标的全局敏感性分析中。依据现行隧道安全评价规范,建立反映隧道安全状态的指标体系;通过基于粒子群优化的最小二乘法支持向量机（PSO-LSSVM）,模拟构建了各安全指标函数拟合模型,用以描述隧道各安全指标之间相互作用关系;在此基础上,采用EFAST对该模型的指标进行了全局敏感性分析。结果发现,对隧道安全性影响较大的敏感因素有管片接缝张开宽度、管片接缝接触应力和隧道沉降值;另外,还分析了不同的目标参数、不同的参数取值范围、不同的输入参数的分布形式对参数敏感度值的影响,从不同的角度揭示了盾构地铁隧道中参数的相互作用机理的演化规律。     

Frequency tracking method and simulation for coriolismass flowmter based on a new adaptive notch filter

In order to improve the long-playing frequency tracking ability in the signal processing for coriolis mass flowmeter (CMF) , a new IIR adaptive notch filter (ANF) is developed via steiglitz-mcBride method (SMM) and applied to filter the sensor output signal whose frequency, amplitude and phase are time-varying following the random walk model. The proposed method can detect the signal frequency fleetly and track the frequency variations continuously. The tracking performances of the proposed method and the adaptive lattice notch filter (LANF) method are investigated with computer simulations. Simulations demonstrate the superiority of the proposed method and show it has advantages of fast convergence rate, insensitivity to initial phase variations, and higher long-playing tracking stability and accuracy than LANF method.     

The simulation of conducted EMI in the ignition system for automotives

The ignition system in automobiles is a main source of electromagnetic interference (EMI), because the electromagnetic emission from the system has the characteristics of high-energy and wide-bandwidth. A method for EMI prediction based on its components’ circuit models is presented. First, the characteristics of the components are analyzed and the equivalent circuits are drew; then, the parasitic parameters of the electromagnetic device are extracted from measurement, analytical solution or finite element method (FEM); and finally, the circuit model of the whole ignition system model in high frequency condition is established. This model is verified by the measurement and simulation results in time domain and in frequency domain.