共查询到20条相似文献,搜索用时 15 毫秒
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ICA的近红外光谱分析软件的研制 总被引:1,自引:0,他引:1
研制了基于独立分量分析方法的近红外光谱分析软件.该软件包括光谱解析、光谱建模和未知成分含量测定三个模块,使用了小波分析、ICA和BP神经网络等数据处理方法.将这种软件用于实测的玉米近红外光谱分析,所得结果令人满意.使用LabVIEW与MATLAB软件混合编程,充分利用了各软件的优点,不仅程序简单,而且界面友好. 相似文献
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近红外光谱数据处理的独立分量分析方法研究 总被引:2,自引:1,他引:1
从数学的角度分析比较了主成分分析(PCA)与独立分量分析(ICA)的原理和特点,给出光谱矩阵在两种不同分析方法下的不同分解;同时结合线性回归和神经网络回归,提出"两步法"来确定不同成分含量测定的最优模型.进而采用PCA与ICA对实际测得的玉米近红外光谱进行了处理,比较分析了两种不同分解所得矩阵的化学含义,以及PCA与ICA两种不同分解对玉米光谱分析结果的影响.仿真结果表明,ICA从独立性角度对光谱数据矩阵进行分解,所得结果更接近实际光谱.最后,利用"两步法"对玉米三种主要成分水、淀粉、蛋白质分别建立了各自最优含量测定模型.结果表明,所建模型符合快速测定要求,具有一定的实用价值. 相似文献
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We have determined the glucose concentration of whole blood from mid-infrared spectra without sample preparation or use of chemical reagents. We selected 1119-1022 cm(-1) as the optimal wavelength range for our measurement by making a first-loading vector analysis based on partial least-squares regression. We examined the influence of hemoglobin on samples by using different calibration and prediction sets. The accuracy of glucose prediction depended on the hemoglobin level in the calibration model; the sample set should represent the entire range of hemoglobin concentration. We obtained an accuracy of 5.9% in glucose prediction, and this value is well within a clinically acceptable range. 相似文献
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Amneh Al-Mbaideen Mohammed Benaissa 《Chemometrics and Intelligent Laboratory Systems》2011,105(1):131-135
In this paper, a new model based on independent component regression (ICR) is proposed to predict the glucose concentration from near infrared (NIR) spectra. The efficiency of the proposed model is validated using mixtures composed of glucose, urea and triacetin. The whole experiments were carried out in a non-controlled environment or sample conditions to show that the proposed model can suppress effectively most of the experimental variations. The proposed model decreases the standard error of prediction (SEP) from 35.59 mg/dL for Partial Least Square regression (PLS) and from 29.1 mg/dL for ICR to only 24.1 mg/dL. 相似文献
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简要介绍了独立分量分析的基本原理及算法,探讨了结构的正规坐标与独立分量的关系。分析认为,结构自由振动响应的振型分解可以看做是一个ICA问题。因此,可以把独立分量分析发展成为一种利用结构自由振动响应时域信号进行模态参数识别的方法。结合数值仿真算例及振动试验,验证了独立分量分析用于结构模态参数识别的有效性。结果表明,独立分量分析可以准确的从结构自振响应中,分离出各正规坐标,同时估计出各阶模态振型向量,适用于环境激励下的工作模态参数识别。 相似文献
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针对故障分析信号中存在噪声问题,提出一种将相空间重构与独立分量分析相结合的局部独立投影降噪算法。其中相空间重构的目的在于从高维相空间中恢复混沌吸引子,独立分量分析能够找到信号的主流形,选择邻域是为了将特征相近的相点结合在一起。使用该方法对正弦仿真信号和Lorenz仿真信号进行降噪处理,结果表明局部独立投影降噪算法的降噪效果与局部独立分量分析算法降噪效果接近,但优于全局投影降噪算法。运用该方法对低速重载轴承振动信号进行分析,准确判断出轴承故障。 相似文献
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荧光造影图像分析是一种重要的糖尿病眼底病变测试方法,针对荧光造影图像易受噪声污染以及白内障病变影响导致眼底视网膜图像辨识困难等问题,基于盲信号处理理论,运用维纳滤波与独立分量分析进行降噪,并运用FASTICA算法进行源信号提取.测试图像处理结果表明:该方法能够有效地抑制噪声,提高分离图像的信噪比,且较好地恢复原始图像. 相似文献
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结构健康监测中常用声发射信号进行声发射源的定位及特征描述。多个冲击事件发生时,声发射信号是多个信号的混叠,而且混合方式未知,这使利用声发射信号对冲击源进行定位变得非常困难。而近年来兴起的基于独立分量分析的盲源分离技术为解决这一难题提供了可能。本文采用基于信息极大化原理的反馈网络结构对同时作用在铝梁上的两个冲击事件产生的声发射混合信号进行分离,估计出各个源信号到达传感器的时延后,运用两点直线定位公式对两个冲击源进行定位。混合仿真实验验证了基于信息极大化原理的独立分量分析方法估计时延的有效性,铝梁上的两源冲击实验,进一步表明运用独立分量分析方法能较好的解决多冲击源定位问题。 相似文献
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提出一种基于独立分量分析与相关系数的机械故障特征提取方法。首先对不同工况的机械振动信号分别进行独立分量分析,获得各种工况信号的独立分量,这些独立分量中蕴含了该工况的一些内在特征;接着利用样本与不同工况信号提取的独立分量的相关系数绝对值的和作为该样本的特征,与直接利用相关系数作为特征相比鲁棒性与区分程度都得到提高;最后使用支持向量机作为分类器进行识别。分别进行了齿轮故障特征提取与轴承故障特征提取实验,实验结果表明,此方法可以很好地提取机械故障特征信息。本文方法的优点在于直接从振动信号的原始数据中进行特征提取,获取机械故障蕴含的一些特征,应用范围广,具有较高地工程应用价值。 相似文献
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Recently, the independent component analysis (ICA) has been widely used for non-Gaussian multivariate process monitoring. An elliptical type measure is traditionally used for ICA-based process monitoring. However, it will not work appropriately since the extracted ICA components exhibit skewed distribution. Thus, this study aims to develop a novel process monitoring scheme for ICA. The basic idea of the proposed method is to first screen out outliers in order to describe well majority for training dataset. Hereafter, a rectangular type measure is applied to monitor the process. The efficiency of proposed monitoring scheme will be implemented via a five variables simulation example and a case study of Tennessee Eastman process. Results indicate that the proposed method cannot only deal with the contaminated training dataset but also shows superior fault detection ability when compared with alternative methods. 相似文献
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Abstract An independent component analysis (ICA) method for image separation by geometric transformation of a scatter diagram is proposed. Geometric transformation and normalization are used to project mixed image signals to independent component space. This method includes four procedures: data correction, whitening, geometric rotation, and slant compensation. Several synthetic mixed image and real applications are used to evaluate the performance of the proposed method. From experimental results, mixed images are separated accurately by the proposed method. 相似文献
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The effect of the presence of metabolism-induced concentration correlations in the calibration samples on the prediction performance of partial least-squares regression (PLSR) models and mid-infrared spectra from Chinese hamster ovary cell cultures was investigated. Samples collected from batch cultures contained highly correlated metabolite concentrations as a result of metabolic relations. Calibrations based on such samples could only be used to predict concentrations in new samples if a similar correlation structure was present and failed when the new samples were randomly spiked with the analytes. On the other hand, such models were able to predict glucose correctly even if they were based on a spectral range in which glucose does not absorb, provided that the correlations in the calibration and in the new samples were similar. If however, samples from a calibration culture were randomly spiked with the main analytes, much more robust PLSR models resulted. It was possible to predict analyte concentrations in new samples irrespective of whether the correlation structure was maintained or not. Validity of all established models for any given use could be predicted a priori by computing the space inclusion and observer conditions. Predictions from these computations agreed in all cases with the experimental test of model validity. 相似文献