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Just-in-time learning based integrated MPC-ILC control for batch processes 被引量:4
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作者 Li Jia Wendan Tan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第8期1713-1720,共8页
Considering the two-dimension(2 D) characteristic and the unknown optimal trajectory problem of the batch processes, an integrated model predictive control-iterative learning control(MPC-ILC) for batch processes is pr... Considering the two-dimension(2 D) characteristic and the unknown optimal trajectory problem of the batch processes, an integrated model predictive control-iterative learning control(MPC-ILC) for batch processes is proposed in this paper. Firstly, the batch-axis information and time-axis information are combined into one quadratic performance index. It implies the integration of ILC and MPC algorithm idea, which leads to superior tracking performance and better robustness against disturbance and uncertainty. To address the problem of the unknown optimal trajectory, both time-varying prediction horizon and end product quality control are employed. Moreover, an integrated 2 D just-in-time learning(JITL) model is used to improve the predictive accuracy. Furthermore, rigorous description and proof are presented to prove the convergence and tracking performance of the proposed MPC-ILC strategy. The simulation results show the effectiveness of the proposed method. 展开更多
关键词 Model predictive control Batch process just-in-time learning (jitl model
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Online Batch Process Monitoring Based on Just-in-Time Learning and Independent Component Analysis 被引量:1
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作者 WANG Li SHI Hong-bo 《Journal of Donghua University(English Edition)》 EI CAS 2016年第6期944-948,共5页
A new method was developed for batch process monitoring in this paper. In the devdopad method, just-in-time learning ( JITL ) and independent component analysis (ICA) were integrated to build JITL-ICA monitoring s... A new method was developed for batch process monitoring in this paper. In the devdopad method, just-in-time learning ( JITL ) and independent component analysis (ICA) were integrated to build JITL-ICA monitoring scheme. JITL was employed to tackle with the characteristics of batch process such as inherent time- varying dynamics, multiple operating phases, and especially the case of uneven length stage. According to new coming test data, the most correlated segmentation was obtained from batch-wise unfolded training data by JITL. Then, ICA served as the principal components extraction approach. Therefore, the non.Gaussian distributed data can also be addressed under this modeling framework. The effectiveness and superiority of JITL-ICA based monitoring method was demonstrated by fed-batch penicillin fermentation. 展开更多
关键词 batch process monitoring just-in-time learning(jitl) independent component analysis(ICA)
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Supervised local and non-local structure preserving projections with application to just-in-time learning for adaptive soft sensor 被引量:4
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作者 邵伟明 田学民 王平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1925-1934,共10页
In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring... In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring important output information, which may lead to inaccurate construction of relevant sample set. To solve this problem, we propose a novel supervised feature extraction method suitable for the regression problem called supervised local and non-local structure preserving projections(SLNSPP), in which both input and output information can be easily and effectively incorporated through a newly defined similarity index. The SLNSPP can not only retain the virtue of locality preserving projections but also prevent faraway points from nearing after projection,which endues SLNSPP with powerful discriminating ability. Such two good properties of SLNSPP are desirable for JITL as they are expected to enhance the accuracy of similar sample selection. Consequently, we present a SLNSPP-JITL framework for developing adaptive soft sensor, including a sparse learning strategy to limit the scale and update the frequency of database. Finally, two case studies are conducted with benchmark datasets to evaluate the performance of the proposed schemes. The results demonstrate the effectiveness of LNSPP and SLNSPP. 展开更多
关键词 Adaptive soft sensor just-in-time learning Supervised local and non-local structure preserving projections Locality preserving projections Database monitoring
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Implementing Augmented Reality in Learning
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作者 Ajit Singh 《Psychology Research》 2019年第4期172-177,共6页
Technologies are changing and ever growing.One of the newest developing technologies is augmented reality(AR),which can be applied to many different existing technologies,such as computers,tablets,and smartphones.AR t... Technologies are changing and ever growing.One of the newest developing technologies is augmented reality(AR),which can be applied to many different existing technologies,such as computers,tablets,and smartphones.AR technology can also be utilized through wearable components,for example,glasses.Throughout this paper review on AR,the following aspects are discussed at length:research explored,theoretical foundations,applications in education,challenges,reactions,and implications.Several different types of AR devices and applications are discussed at length,and an in-depth analysis is done on several studies that have implemented AR technology in an educational setting. 展开更多
关键词 AUGMENTED REALITY learning and development EDUCATOR flow theory just-in-time learning
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基于非高斯信息的JITL软测量模型 被引量:2
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作者 李元 张新民 《上海交通大学学报》 EI CAS CSCD 北大核心 2015年第6期897-901,共5页
为了有效监控具有非高斯数据特性的工业过程,提出了一种新的基于非高斯信息的JITL(Just-In-Time Learning)软测量模型.首先通过非高斯非相似度测量选择JITL局部建模样本;然后建立局部ICA-PLS回归模型实现工业过程质量变量监控.该方法从... 为了有效监控具有非高斯数据特性的工业过程,提出了一种新的基于非高斯信息的JITL(Just-In-Time Learning)软测量模型.首先通过非高斯非相似度测量选择JITL局部建模样本;然后建立局部ICA-PLS回归模型实现工业过程质量变量监控.该方法从局部建模样本选择到局部回归模型建立能够有效处理工业过程数据的非高斯特性,并且保留了JITL建模的优点,能够有效地处理工业过程时变特性以及非线性.通过硫回收处理过程的应用,验证了方法的有效性. 展开更多
关键词 非高斯非相似度测量 jitl 质量预测 硫回收处理过程
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Local multi-model integrated soft sensor based on just-in-time learning for mechanical properties of hot strip mill process 被引量:1
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作者 Jie Dong Ying-ze Tian Kai-xiang Peng 《Journal of Iron and Steel Research International》 SCIE EI CSCD 2021年第7期830-841,共12页
The mechanical properties of hot rolled strip are the key index of product quality,and the soft sensing of them is an important decision basis for the control and optimization of hot rolling process.To solve the probl... The mechanical properties of hot rolled strip are the key index of product quality,and the soft sensing of them is an important decision basis for the control and optimization of hot rolling process.To solve the problem that it is difficult to measure the mechanical properties of hot rolled strip in time and accurately,a soft sensor based on ensemble local modeling was proposed.Firstly,outliers of process data are removed by local outlier factor.After standardization and transformation,normal data that can be used in the model are obtained.Next,in order to avoid redundant variables participating in modeling and reducing performance of models,feature selection was applied combing the mechanism of hot rolling process and mutual information among variables.Then,features of samples were extracted by supervised local preserving projection,and a prediction model was constructed by Gaussian process regression based on just-in-time learning(JITL).Other JITL-based models,such as support vector regression and gradient boosting regression tree models,keep all variables and make up for the lost information during dimension reduction.Finally,the soft sensor was developed by integrating individual models through stacking method.Superiority and reliability of proposed soft sensors were verified by actual process data from a real hot rolling process. 展开更多
关键词 Soft sensor just-in-time learning MULTI-MODEL Hot rolling
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基于数据的湿法冶金全流程操作量优化设定补偿方法 被引量:8
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作者 李康 王福利 +1 位作者 何大阔 贾润达 《自动化学报》 EI CSCD 北大核心 2017年第6期1047-1055,共9页
湿法冶金过程具有反应机理复杂、工艺流程长、工序众多等特点,由于模型误差等因素,基于模型得到的生产过程最优工作点不是实际生产过程的最优工作点.如何保持湿法冶金生产流程运行在经济效益最优的状态成为生产优化控制的难点.本文提出... 湿法冶金过程具有反应机理复杂、工艺流程长、工序众多等特点,由于模型误差等因素,基于模型得到的生产过程最优工作点不是实际生产过程的最优工作点.如何保持湿法冶金生产流程运行在经济效益最优的状态成为生产优化控制的难点.本文提出了一种基于数据的湿法冶金过程操作量优化设定补偿方法.该方法在基于模型得到的最优工作点基础上,采用即时学习(Just-in-time learning,JITL)的思想,在当前工作点附近利用历史数据建立操作量补偿值和经济效益增量的相关模型,优化求解在当前工作点下,使经济效益增量最大化的操作量补偿值,施加到生产流程,并在新工作点进行迭代补偿.将所提出的方法仿真应用于某精炼厂的湿法冶金生产流程,仿真结果验证了所提出方法的有效性. 展开更多
关键词 湿法冶金 基于数据 优化补偿 即时学习
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时变过程在线辨识的即时递推核学习方法研究 被引量:9
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作者 刘毅 金福江 高增梁 《自动化学报》 EI CSCD 北大核心 2013年第5期602-609,共8页
为了及时跟踪非线性化工过程的时变特性,提出即时递推核学习(Kernel learning,KL)的在线辨识方法.针对待预测的新样本点,采用即时学习(Just-in-time kernel learning,JITL)策略,通过构造累积相似度因子,选择与其相似的样本集建立核学习... 为了及时跟踪非线性化工过程的时变特性,提出即时递推核学习(Kernel learning,KL)的在线辨识方法.针对待预测的新样本点,采用即时学习(Just-in-time kernel learning,JITL)策略,通过构造累积相似度因子,选择与其相似的样本集建立核学习辨识模型.为避免传统即时学习对每个待预测点都重新建模的繁琐,利用两个临近时刻相似样本集的异同点,采用递推方法有效添加新样本,并删减旧模型的样本,以快速建立新即时模型.通过一时变连续搅拌釜式反应过程的在线辨识,表明了所提出方法在保证计算效率的同时,较传统递推核学习方法提高了辨识的准确程度,能更好地辨识时变过程. 展开更多
关键词 过程辨识 即时学习 核学习 最小二乘支持向量回归 递推辨识
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基于时间差分和局部加权偏最小二乘算法的过程自适应软测量建模 被引量:17
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作者 袁小锋 葛志强 宋执环 《化工学报》 EI CAS CSCD 北大核心 2016年第3期724-728,共5页
工业过程软测量模型常常因为过程的变量漂移、非线性和时变等问题而使得预测性能下降。因此,时间差分已被应用于解决过程变量漂移问题。但是,时间差分框架下的全局模型往往不能很好地描述过程非线性和时变等特性。为此,提出了一种融合... 工业过程软测量模型常常因为过程的变量漂移、非线性和时变等问题而使得预测性能下降。因此,时间差分已被应用于解决过程变量漂移问题。但是,时间差分框架下的全局模型往往不能很好地描述过程非线性和时变等特性。为此,提出了一种融合时间差分模型和局部加权偏最小二乘算法的自适应软测量建模方法。时间差分模型可以大大减少过程变量漂移的影响,而局部加权偏最小二乘算法作为一种即时学习方法,可以有效解决过程非线性和时变问题。该方法的有效性在数值例子和工业过程实例中得到了有效验证。 展开更多
关键词 时间差分模型 局部加权偏最小二乘算法 即时学习 软测量建模 质量预测
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基于邻域保持嵌入算法的间歇过程故障检测 被引量:3
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作者 梁秀霞 郑向博 郑晓慧 《自动化与仪表》 2015年第10期1-4,27,共5页
该文针对间歇过程数据的高维非线性特征以及传统数据预处理方法的不足,提出了一种基于即时学习的邻域正交保持嵌入(ONPE)算法。ONPE算法是一种基于几何思想来描述数据特征的维度约简算法,目的在于保持过程数据的局部特性,适用于非线性系... 该文针对间歇过程数据的高维非线性特征以及传统数据预处理方法的不足,提出了一种基于即时学习的邻域正交保持嵌入(ONPE)算法。ONPE算法是一种基于几何思想来描述数据特征的维度约简算法,目的在于保持过程数据的局部特性,适用于非线性系统,能更好地提取数据分布特征和本质信息。另外,针对间歇过程的时变特性和多时段特性,该文将即时学习算法应用其中,通过监控统计量T2和SPE检测故障。最后通过对青霉素生产过程进行仿真证明能够取得良好的监控性能和预测性能。 展开更多
关键词 间歇过程 即时学习 邻域保持嵌入
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基于即时学习的间歇过程复合模型 被引量:2
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作者 付钊 贾立 《上海交通大学学报》 EI CAS CSCD 北大核心 2016年第6期937-942,948,共7页
通过传统的即时学习(JITL)方法建立间歇过程复合的线性化模型,利用一个具有5层结构的神经模糊模型(NFM)对局部模型的输出误差特性进行分析,建立模型输入与输出误差之间的非线性映射关系,并通过对模型的预测输出进行误差补偿来提高模型精... 通过传统的即时学习(JITL)方法建立间歇过程复合的线性化模型,利用一个具有5层结构的神经模糊模型(NFM)对局部模型的输出误差特性进行分析,建立模型输入与输出误差之间的非线性映射关系,并通过对模型的预测输出进行误差补偿来提高模型精度.仿真结果表明,所提出的基于JITL的间歇过程复合模型相对于传统JITL模型具有更高的精度和更强的噪声抑制能力. 展开更多
关键词 间歇过程 即时学习 神经模糊模型 误差补偿 线性化
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基于改进即时学习的海洋碱性蛋白酶菌体浓度广义预测控制
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作者 朱湘临 蔡可 王博 《传感器与微系统》 CSCD 北大核心 2021年第12期81-84,88,共5页
针对微生物发酵过程中普遍存在的时变性、非线性等问题,基于最小二乘回归算法和改进即时学习(JITL)策略设计出一种基质给进速率控制器。首先,通过发酵仪器采集数据形成历史数据库,再使用加权模糊C均值聚类(WFCM)算法对数据进行分类,使... 针对微生物发酵过程中普遍存在的时变性、非线性等问题,基于最小二乘回归算法和改进即时学习(JITL)策略设计出一种基质给进速率控制器。首先,通过发酵仪器采集数据形成历史数据库,再使用加权模糊C均值聚类(WFCM)算法对数据进行分类,使查询值到来时能快速建立基于JITL-LS-SVM的海洋碱性蛋白酶菌体浓度局部预测模型。同时,为了避免预测控制中求解非线性问题,采用泰勒线性化方法,并用广义预测(GPC)算法对海洋碱性蛋白酶菌体浓度进行预测控制。实验仿真表明:基于改进JITL的JITL-LS-SVM模型能够达到较好的控制效果,并且葡萄糖给进速率响应迅速,适合海洋碱性蛋白酶发酵过程中的基质流加补料控制。 展开更多
关键词 最小二乘回归 改进即时学习 广义预测控制 海洋碱性蛋白酶
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基于即时学习的高炉炼铁过程数据驱动自适应预测控制 被引量:18
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作者 易诚明 周平 柴天佑 《控制理论与应用》 EI CAS CSCD 北大核心 2020年第2期295-306,共12页
针对高炉炼铁过程,本文提出一种基于即时学习的高炉铁水质量自适应预测控制方法(JITL–APC).该方法的特点是控制器通过k向量近邻(k–VNN)方法搜索数据库中的输入输出(I/O)数据信息,对非线性系统进行局部建模,并在此基础上计算控制律.而... 针对高炉炼铁过程,本文提出一种基于即时学习的高炉铁水质量自适应预测控制方法(JITL–APC).该方法的特点是控制器通过k向量近邻(k–VNN)方法搜索数据库中的输入输出(I/O)数据信息,对非线性系统进行局部建模,并在此基础上计算控制律.而且,该方法中引入了工业异常数据处理机制,利用JITL学习子集中的平均数据项,对异常数据项进行填补或替换,从而消除异常数据对控制系统的影响.此外,本文提出一种JITL模型保留策略(MRS),避免由于数据库中相似数据样本不足导致的局部模型严重失配,并通过实时收集I/O数据更新数据库,使控制器自适应不同的工况条件,MRS还可以有效抑制噪声干扰的影响,从而提高控制系统的稳定性.最后,基于某大型钢铁厂2#高炉的数值仿真实验,充分验证了该方法的有效性. 展开更多
关键词 高炉 数据驱动 即时学习 线性化 模型预测控制 工业数据异常
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基于改进即时学习算法的镨/钕元素组分含量预测 被引量:11
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作者 陆荣秀 饶运春 +2 位作者 杨辉 朱建勇 杨刚 《控制理论与应用》 EI CAS CSCD 北大核心 2020年第8期1846-1854,共9页
针对镨/钕(Pr/Nd)萃取过程元素组分含量难以在线实时检测的现状,引入加权相似度准则和局部模型更新策略,提出一种基于改进即时学习算法的稀土元素组分含量快速估计方法.首先,为了保证即时学习算法学习集选取的合理性,充分考虑输入输出... 针对镨/钕(Pr/Nd)萃取过程元素组分含量难以在线实时检测的现状,引入加权相似度准则和局部模型更新策略,提出一种基于改进即时学习算法的稀土元素组分含量快速估计方法.首先,为了保证即时学习算法学习集选取的合理性,充分考虑输入输出变量之间的相关程度,采用互信息加权的相似度准则选择建模邻域,以最小二乘支持向量机(LSSVM)作为即时学习算法的局部模型;其次,依据由相似度阈值更新和数据库更新组成的模型更新策略校正LSSVM局部模型,改善组分含量预测模型的精度和实时性;最后,基于镨/钕萃取现场数据进行仿真对比试验,结果表明所建模型具有精度高、实时性好等优点,适用于稀土萃取生产现场元素组分含量的快速预估. 展开更多
关键词 即时学习 萃取过程 组分含量 预测 相似度准则 局部模型更新策略
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Effort-aware cross-project just-in-time defect prediction framework for mobile apps
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作者 Tian CHENG Kunsong ZHAO +2 位作者 Song SUN Muhammad MATEEN Junhao WEN 《Frontiers of Computer Science》 SCIE EI CSCD 2022年第6期15-29,共15页
As the boom of mobile devices,Android mobile apps play an irreplaceable roles in people’s daily life,which have the characteristics of frequent updates involving in many code commits to meet new requirements.Just-in-... As the boom of mobile devices,Android mobile apps play an irreplaceable roles in people’s daily life,which have the characteristics of frequent updates involving in many code commits to meet new requirements.Just-in-Time(JIT)defect prediction aims to identify whether the commit instances will bring defects into the new release of apps and provides immediate feedback to developers,which is more suitable to mobile apps.As the within-app defect prediction needs sufficient historical data to label the commit instances,which is inadequate in practice,one alternative method is to use the cross-project model.In this work,we propose a novel method,called KAL,for cross-project JIT defect prediction task in the context of Android mobile apps.More specifically,KAL first transforms the commit instances into a high-dimensional feature space using kernel-based principal component analysis technique to obtain the representative features.Then,the adversarial learning technique is used to extract the common feature embedding for the model building.We conduct experiments on 14 Android mobile apps and employ four effort-aware indicators for performance evaluation.The results on 182 cross-project pairs demonstrate that our proposed KAL method obtains better performance than 20 comparative methods. 展开更多
关键词 kernel-based principal component analysis adversarial learning just-in-time defect prediction cross-project model
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