There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because the...There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because their presumptions are that sampled-data should obey the single Gaussian distribution or non-Gaussian distribution. In order to solve these problems, a novel weighted local standardization(WLS) strategy is proposed to standardize the multimodal data, which can eliminate the multi-mode characteristics of the collected data, and normalize them into unimodal data distribution. After detailed analysis of the raised data preprocessing strategy, a new algorithm using WLS strategy with support vector data description(SVDD) is put forward to apply for multi-mode monitoring process. Unlike the strategy of building multiple local models, the developed method only contains a model without the prior knowledge of multi-mode process. To demonstrate the proposed method's validity, it is applied to a numerical example and a Tennessee Eastman(TE) process. Finally, the simulation results show that the WLS strategy is very effective to standardize multimodal data, and the WLS-SVDD monitoring method has great advantages over the traditional SVDD and PCA combined with a local standardization strategy(LNS-PCA) in multi-mode process monitoring.展开更多
Complex industry processes often need multiple operation modes to meet the change of production conditions. In the same mode,there are discrete samples belonging to this mode. Therefore,it is important to consider the...Complex industry processes often need multiple operation modes to meet the change of production conditions. In the same mode,there are discrete samples belonging to this mode. Therefore,it is important to consider the samples which are sparse in the mode.To solve this issue,a new approach called density-based support vector data description( DBSVDD) is proposed. In this article,an algorithm using Gaussian mixture model( GMM) with the DBSVDD technique is proposed for process monitoring. The GMM method is used to obtain the center of each mode and determine the number of the modes. Considering the complexity of the data distribution and discrete samples in monitoring process,the DBSVDD is utilized for process monitoring. Finally,the validity and effectiveness of the DBSVDD method are illustrated through the Tennessee Eastman( TE) process.展开更多
为解决传统航空发动机异常检测方法准确率和泛化性能较低的问题,提出一种混合核最大相关熵的深度支持向量数据描述(mixed kernel maximum correntropy criterion-deep support vector data description,MKMCC-DSVDD)方法。首先,采用合...为解决传统航空发动机异常检测方法准确率和泛化性能较低的问题,提出一种混合核最大相关熵的深度支持向量数据描述(mixed kernel maximum correntropy criterion-deep support vector data description,MKMCC-DSVDD)方法。首先,采用合成少数类过采样技术扩充异常样本规模,提高对非均衡样本的泛化性能;其次,建立基于混合核改进的最大相关熵损失函数,可以在无须数据分布假设的前提下提升准确率;最后,构建基于MKMCC-DSVDD的航空发动机异常检测方法。在航空发动机气路系统和滑油系统异常检测实验中,所提方法平均曲线下的面积(area under curve,AUC)达到98.53%,表明其具有较高的实用性和泛化性能。展开更多
为了进一步提高电动汽车轮毂电机轴承状态识别技术的高效可靠性,提出一种基于双核支持向量数据描述(double kernel based support vector data description,简称DK-SVDD)的轮毂电机轴承状态识别方法。首先,针对轮毂电机轴承样本数据结...为了进一步提高电动汽车轮毂电机轴承状态识别技术的高效可靠性,提出一种基于双核支持向量数据描述(double kernel based support vector data description,简称DK-SVDD)的轮毂电机轴承状态识别方法。首先,针对轮毂电机轴承样本数据结构混杂致使SVDD识别率较低问题,通过一定的比例权重将径向基(radial basis function,简称RBF)核函数和高斯差分(difference of Gaussians,简称DOG)核函数结合构建DK核函数;其次,根据最优二叉树原理逐层设计状态识别分类器,并搭建DK-SVDD轮毂电机轴承状态识别模型,同时使用粒子群优化算法对模型参数寻优以提高DK-SVDD的学习能力和泛化能力;最后,基于轮毂电机轴承台架试验数据,验证所提方法的有效性和优越性。结果表明:针对轮毂电机轴承目标状态识别,DK-SVDD方法平均训练时间为0.0655 s,平均状态识别率为97.06%;与采用RBF或DOG核函数相比,DK-SVDD方法在多种工况下可以有效提高状态识别率并降低训练时间。展开更多
为提升代价敏感分类性能,通过提升较高误分代价类别的学习精度来降低总误分代价,利用支持向量域描述(Support Vector D omain Description,SVDD)实现代价敏感分类,提出一种代价敏感SVDD二类分类方法CS-SVDD。该方法首先将单类SVDD拓展...为提升代价敏感分类性能,通过提升较高误分代价类别的学习精度来降低总误分代价,利用支持向量域描述(Support Vector D omain Description,SVDD)实现代价敏感分类,提出一种代价敏感SVDD二类分类方法CS-SVDD。该方法首先将单类SVDD拓展为二类分类SVDD,对不同类别分别构建SVDD超球体,通过误分类代价调节SVDD分类器对不同类别样本的分类精度,对误分代价高的类别进行更为精确的学习,从而降低总误分代价;对于处于两个超球体之外或覆盖区域的类别属性不明确的样本,以误分代价最小为原则定义代价敏感决策规则。在人工数据集和UCI数据集上与同类方法进行了实验比较,实验结果表明了所提方法的有效性。展开更多
针对支持向量数据描述(Support Vector Data Description,SVDD)在线学习时的支持向量数量随样本规模的扩大呈线性增加,进而导致模型更新时间呈非线性增长的问题,提出一种基于支持向量约减的支持向量数据描述(R-SVDD)在线学习方法。该算...针对支持向量数据描述(Support Vector Data Description,SVDD)在线学习时的支持向量数量随样本规模的扩大呈线性增加,进而导致模型更新时间呈非线性增长的问题,提出一种基于支持向量约减的支持向量数据描述(R-SVDD)在线学习方法。该算法通过执行支持向量约减,控制在线学习时的支持向量数量,从而使其具有比其他SVDD算法更快速且更稳定的模型更新时间,适合大规模数据的分类处理。首先阐述了支持向量约减的原理;进而给出了在线R-SVDD算法。在单分类和多分类数据集上的实验结果表明,R-SVDD算法相较于SVDD算法,能够在保持分类精度的基础上拥有更快的学习速度。展开更多
利用常规方法检测网络数据流异常存在检测效率低的问题,为此提出基于改进支持向量数据描述(Support Vector Data Description,SVDD)算法的网络数据流异常检测方法。首先,选取一对一的构造方法将通信网络异常流量数据分为两个类别;其次,...利用常规方法检测网络数据流异常存在检测效率低的问题,为此提出基于改进支持向量数据描述(Support Vector Data Description,SVDD)算法的网络数据流异常检测方法。首先,选取一对一的构造方法将通信网络异常流量数据分为两个类别;其次,根据数据流的处理标准和需求,采用聚类分析技术构建监测模型;最后,通过改进SVDD流量异常检测模型对经过聚类特征提取的数据进行识别和检测。实验结果表明,该方法的检测准确率均高于97.5%,检测耗时较短,优于对照组。展开更多
基金Project(61374140)supported by the National Natural Science Foundation of China
文摘There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because their presumptions are that sampled-data should obey the single Gaussian distribution or non-Gaussian distribution. In order to solve these problems, a novel weighted local standardization(WLS) strategy is proposed to standardize the multimodal data, which can eliminate the multi-mode characteristics of the collected data, and normalize them into unimodal data distribution. After detailed analysis of the raised data preprocessing strategy, a new algorithm using WLS strategy with support vector data description(SVDD) is put forward to apply for multi-mode monitoring process. Unlike the strategy of building multiple local models, the developed method only contains a model without the prior knowledge of multi-mode process. To demonstrate the proposed method's validity, it is applied to a numerical example and a Tennessee Eastman(TE) process. Finally, the simulation results show that the WLS strategy is very effective to standardize multimodal data, and the WLS-SVDD monitoring method has great advantages over the traditional SVDD and PCA combined with a local standardization strategy(LNS-PCA) in multi-mode process monitoring.
基金National Natural Science Foundation of China(No.61374140)the Youth Foundation of National Natural Science Foundation of China(No.61403072)
文摘Complex industry processes often need multiple operation modes to meet the change of production conditions. In the same mode,there are discrete samples belonging to this mode. Therefore,it is important to consider the samples which are sparse in the mode.To solve this issue,a new approach called density-based support vector data description( DBSVDD) is proposed. In this article,an algorithm using Gaussian mixture model( GMM) with the DBSVDD technique is proposed for process monitoring. The GMM method is used to obtain the center of each mode and determine the number of the modes. Considering the complexity of the data distribution and discrete samples in monitoring process,the DBSVDD is utilized for process monitoring. Finally,the validity and effectiveness of the DBSVDD method are illustrated through the Tennessee Eastman( TE) process.
文摘为解决传统航空发动机异常检测方法准确率和泛化性能较低的问题,提出一种混合核最大相关熵的深度支持向量数据描述(mixed kernel maximum correntropy criterion-deep support vector data description,MKMCC-DSVDD)方法。首先,采用合成少数类过采样技术扩充异常样本规模,提高对非均衡样本的泛化性能;其次,建立基于混合核改进的最大相关熵损失函数,可以在无须数据分布假设的前提下提升准确率;最后,构建基于MKMCC-DSVDD的航空发动机异常检测方法。在航空发动机气路系统和滑油系统异常检测实验中,所提方法平均曲线下的面积(area under curve,AUC)达到98.53%,表明其具有较高的实用性和泛化性能。
文摘由于电网企业不断加快数字化转型,利用北斗定位技术将自动获取区域内光伏计量装置经纬度这一关键技术参数。文章充分利用分布式光伏集群内光伏发电装机位置空间相关性,提出一种在弱监督下基于图滤波与支持向量数据描述(support vector data description,SVDD)的分布式光伏集群发电异常检测方法。首先建立分布式光伏集群发电图数据结构模型,通过加权邻接矩阵描述分布式光伏发电点空间耦合性,其次构造图高通滤波器将时域参数转化为频域参数,然后通过SVDD算法优化图滤波结果,进一步挖掘图高通滤波器阈值与输出功率数据之间的关系。结果表明,采用图滤波器和SVDD算法模型方法在分布式光伏发电异常检测精度上有显著提高。
文摘为了进一步提高电动汽车轮毂电机轴承状态识别技术的高效可靠性,提出一种基于双核支持向量数据描述(double kernel based support vector data description,简称DK-SVDD)的轮毂电机轴承状态识别方法。首先,针对轮毂电机轴承样本数据结构混杂致使SVDD识别率较低问题,通过一定的比例权重将径向基(radial basis function,简称RBF)核函数和高斯差分(difference of Gaussians,简称DOG)核函数结合构建DK核函数;其次,根据最优二叉树原理逐层设计状态识别分类器,并搭建DK-SVDD轮毂电机轴承状态识别模型,同时使用粒子群优化算法对模型参数寻优以提高DK-SVDD的学习能力和泛化能力;最后,基于轮毂电机轴承台架试验数据,验证所提方法的有效性和优越性。结果表明:针对轮毂电机轴承目标状态识别,DK-SVDD方法平均训练时间为0.0655 s,平均状态识别率为97.06%;与采用RBF或DOG核函数相比,DK-SVDD方法在多种工况下可以有效提高状态识别率并降低训练时间。
文摘为提升代价敏感分类性能,通过提升较高误分代价类别的学习精度来降低总误分代价,利用支持向量域描述(Support Vector D omain Description,SVDD)实现代价敏感分类,提出一种代价敏感SVDD二类分类方法CS-SVDD。该方法首先将单类SVDD拓展为二类分类SVDD,对不同类别分别构建SVDD超球体,通过误分类代价调节SVDD分类器对不同类别样本的分类精度,对误分代价高的类别进行更为精确的学习,从而降低总误分代价;对于处于两个超球体之外或覆盖区域的类别属性不明确的样本,以误分代价最小为原则定义代价敏感决策规则。在人工数据集和UCI数据集上与同类方法进行了实验比较,实验结果表明了所提方法的有效性。
文摘针对支持向量数据描述(Support Vector Data Description,SVDD)在线学习时的支持向量数量随样本规模的扩大呈线性增加,进而导致模型更新时间呈非线性增长的问题,提出一种基于支持向量约减的支持向量数据描述(R-SVDD)在线学习方法。该算法通过执行支持向量约减,控制在线学习时的支持向量数量,从而使其具有比其他SVDD算法更快速且更稳定的模型更新时间,适合大规模数据的分类处理。首先阐述了支持向量约减的原理;进而给出了在线R-SVDD算法。在单分类和多分类数据集上的实验结果表明,R-SVDD算法相较于SVDD算法,能够在保持分类精度的基础上拥有更快的学习速度。
文摘利用常规方法检测网络数据流异常存在检测效率低的问题,为此提出基于改进支持向量数据描述(Support Vector Data Description,SVDD)算法的网络数据流异常检测方法。首先,选取一对一的构造方法将通信网络异常流量数据分为两个类别;其次,根据数据流的处理标准和需求,采用聚类分析技术构建监测模型;最后,通过改进SVDD流量异常检测模型对经过聚类特征提取的数据进行识别和检测。实验结果表明,该方法的检测准确率均高于97.5%,检测耗时较短,优于对照组。
