基于LTSA和MICA与PCA联合指标的过程监控方法及应用

独立成分分析(ICA)方法主要被用来对线性非高斯过程进行监控,为了提高对非高斯过程的监控效果,则利用过程数据信息对ICA的监控指标进行了改进,提出了一种改进的独立成分分析(MICA)方法。许多实际工业过程数据都具有非线性、非高斯与高斯混合分布的特点,为此提出了一种基于LTSA和MICA与PCA联合指标的过程监控的方法。首先采用局部切空间排列(LTSA)算法对样本数据进行非线性降维,然后分别用MICA和PCA方法得到非高斯与高斯统计量,对其进行加权得到新的统计量,并被用于过程监控。最后将该方法应用在田纳西-伊斯曼(TE)过程和乙烯裂解炉的过程监控中,证明了该方法的有效性。     

Chemometric analysis of the influence of mechanical activation on the mica quality parameters

The differences in the set of the process parameters measured before and after mica mechanical activation and their influence on the grain size distribution related characteristics have been studied. The modification of the behavior for activated samples has been correlated to the particle size distribution effect produced by activation via an ultra centrifugal mill. The mechanical treatments are energetically and economically unsustainable procedures, therefore the mica activation was optimized on basis of assessment of the process variables effect on the final quality of product parameters. Response surface method, standard score analysis and principal component analysis were used as means of the optimization. Developed models showed r² values in the range of 0.816–0.988 and they were able to accurately predict quality parameters in a wide range of processing parameters. Standard score analysis highlighted that the optimal sample was obtained using sieve mesh of 80 μm set of processing parameters (SS=0.81). Multiple comparison tests revealed that the optimal variation in the processing parameters could reduce the negative effect of mica samples inherent properties on the final score and improve activation procedure energetic and economic sustainability.     

一种基于KICA-GMM的过程故障检测方法

核独立元分析(kernel independent component analysis,KICA)故障检测方法的故障检测时间易受独立元顺序和主导独立元数目经验选取的影响,针对这个问题,提出基于KICA和高斯混合模型(Gaussian mixture model,GMM)的故障检测方法。采用KICA从正常工况测量数据中提取独立元,用GMM拟合各独立元的概率密度函数,建立基于GMM的监控量及其控制限;计算各独立元的监控量均值,以此判断其非高斯性强弱,对每个强非高斯独立元进行单独监控,对弱非高斯部分采用主元分析法进行监控。在Tennessee Eastman过程上的仿真结果说明,相比于KICA故障检测方法,所提方法不需要排序独立元和选取主导独立元数目,避免了其对故障检测时间的影响,能够有效利用过程信息,缩短故障检测的延迟时间。     

黑骨藤化学成分及药理作用研究进展

黑骨藤是苗族地区的常用药,主治风湿关节痛、跌打损伤、月经不调等症。为了更好开发和利用其资源,文章综述了近年来黑骨藤化学成分及药理作用研究方面的进展,并对其发展趋势和前景作了展望。     

电器开关用盖类零件多向抽芯注塑模具设计

分析了电器开关用盖类塑件的使用要求和结构特点,介绍了多向抽芯注塑模具的结构组成及工作原理。该模具采用四板式点浇口,采用外侧三向斜导柱抽芯和内侧弹性元件抽芯两种侧抽芯机构,结构合理,运行可靠。     

随车起重机结构件涂装生产线简介

为提高随车起重机表面质量,涂装前处理采用抛丸清理与化学处理相结合的工艺,彻底去除工件表面锈蚀和油污,并形成一层致密的磷化膜;涂层采用底面合一漆"湿碰湿"涂装工艺,节省投资和运行成本。应用情况表明:生产线工艺流程合理,设备布置紧凑,先进实用。     

浅谈高压管道组成件的设计

比较两种法兰体系标准规范后,简述在高压组成件设计和施工验收中标准规范的选用,并提出相关建议。     

Quantification of valve leakage rates

This article gives an overview of methods concerning the detection and quantification of internal leaks through valves. It also presents comparisons of the methods using new experimental data with emphasis on the spectral information in the signals. The first method utilizes known analytical relationships between acoustic emissions and fluid flow. The second method is a data‐driven comparative approach where an online signal from a leaking valve is compared with a set of saved reference signals from leaking valves. The work presents a new and improved way of leak estimation compared to what is practiced in the industry today, which will ultimately result in safer operations and reduced maintenance related costs. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

Parameters of the Mass-Transfer Through the Reverse Osmosis Polysulphonamid Membrane of the Binary Aquatic Solutions of Salts

Abstract

Experimental data of mass transfer through the reverse osmosis polysulfonmide membrane of binary aqueous solutions of salts are compared with the predictions of phenomenological equations of mass transfer.