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Multi-pass intermittent local loading process of large-scale rib-web component:Forming characteristics and implementing apparatus 认领 引用 被引量：3
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作者 Dawei ZHANG Peng DONG +2 位作者 Jingxiang LI Zijian YU Shengdun ZHAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第1期601-625,共25页
The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and redu... The multi-pass intermittent local loading process,which features a more flexible processing path,can further enhance the second material distribution during local loading,improve the formability of components,and reduce forming loads.However,the absence of compatible forming equipment makes it difficult to control the constraint in the unloaded zones during the forming process.This difficulty complicates coordination and control of deformation,particularly for asymmetric rib-web components.Additionally,the current implementation involves multi-fire heating,a long process flow,and high energy consumption,which limits the popularization and application of the local loading process.In this study,a new multi-pass local loading hydraulic forming apparatus that can quickly and reliably switch between heavy-load deformation and low-load constraint for different local loading sub-dies was developed.A 10-tonne laboratory prototype was developed,and the forming characteristics during the forming process as well as the response characteristics of the hydraulic system during the multi-pass intermittent local loading of rib-web component were investigated using numerical simulations and physical experiments.Results indicated that,compared to a whole loading process with the same initial geometry of billet,the total forming load(i.e.,the sum of loaded and restrained loads)is reduced by more than 40%with the local loading process,and by nearly 50%with multi-pass local loading.The multi-pass local loading process allows for more effective control of material flow compared to single-pass local loading,leading to improved cavity filling and reduced flow line disturbance.For a large-scale,complex titanium alloy bulkhead,the cavity filling problem was addressed by optimizing the multi-pass local loading path with an unequal thickness billet.The dynamic performance of the multi-pass local loading hydraulic system was found to be robust,with stable pressure transitions during motion and load switching for the sub-die(s).The dynamic characteristic of the hydraulic cylinder when switching from non-moving/unloaded state to a moving/loading state are consistent whether a load is present or not.However,the dynamic characteristics differ when switching from a moving/loading state to non-moving/unloaded state,showing opposite behavior.The developed hydraulic drive mechanism provides a way for implementation of multi-pass local loading without auxiliary operation and extra heating.The results of the study provide a foundation for the industrial production of large-scale,complex components with reduced force requirement and low-energy consumption. 展开更多
关键词 Forming characteristics Hydraulic system Intermittent local loading process Material flow Rib-web component
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Study on dynamic changes and correlations of microbial diversity,key enzyme activity and conventional components in tobacco leaves during the aging process 认领 引用
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作者 Wen Cai Qian-ying Zhang +4 位作者 Peng-cheng Zhu Wanrong Hu Hongyue An Dan-Qun Huo Dongliang Li 《Bioresources and Bioprocessing》 SCIE EI CSCD 2025年第1期2109-2125,共17页
This study focuses on the aging process of strong-flavor flue-cured tobacco leaves(SCTL)and light-flavor flue-cured tobacco leaves(FCTL),and explores the effects of microbial metabolism and enzyme action on tobacco le... This study focuses on the aging process of strong-flavor flue-cured tobacco leaves(SCTL)and light-flavor flue-cured tobacco leaves(FCTL),and explores the effects of microbial metabolism and enzyme action on tobacco leaf components and quality during this process.It employs methods including high-throughput sequencing,functional prediction of microbial communities via the PICRUSt2/MetaCyc database,dynamic analysis of conventional components and enzyme activities,and redundancy analysis.The results showed that under the same aging duration,the microbial community diversity structures of tobacco leaves with different quality grades were similar,and a total of 21 species of differential bacteria and 9 species of differential fungi were screened out;During the aging process,the contents of starch and total phenols in tobacco leaves decreased significantly,reducing sugars and total sugars showed a fluctuating trend,while total nitrogen and total plant alkaloids had no significant changes.Among them,the starch content in SCTL was higher than that in FCTL,while the contents of total phenols,reducing sugars and total sugars in SCTL were lower than those in FCTL;the contents of total nitrogen and total plant alkaloids were comparable between the two types of tobacco leaves.Additionally,the contents of reducing sugars,total sugars and starch in both types of tobacco leaves were positively correlated with tobacco leaf grade,while the contents of total phenols and total nitrogen were negatively correlated with tobacco leaf grade;The enzyme activities in the two types of tobacco leaves showed fluctuating changes during aging,and redundancy analysis(RDA)identified significant correlations between microbial taxa,enzyme activities and tobacco leaf compounds.This study provides a basis for microbial strain selection and precision fermentation strategies in tobacco aging. 展开更多
关键词 Aging process Microbial diversity Enzyme activity Conventional components Correlation analysis
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Effects of different thermal processing methods on bioactive components,phenolic compounds,and antioxidant activities of Qingke(highland hull-less barley) 认领 引用 被引量：10
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作者 Qingyue Hong Guangjing Chen +2 位作者 Zhirong Wang Xuhui Chen Jianquan Kan 《Food Science and Human Wellness》 SCIE CAS CSCD 2023年第1期119-129,共11页
Qingke(highland hull-less barley)is a grain replete with substantial nutrients and bioactive ingredients.In this study,we evaluated the effects of boiling(BO),steaming(ST),microwave baking(MB),far-infrared baking(FB),... Qingke(highland hull-less barley)is a grain replete with substantial nutrients and bioactive ingredients.In this study,we evaluated the effects of boiling(BO),steaming(ST),microwave baking(MB),far-infrared baking(FB),steam explosion(SE),and deep frying(DF)on bioactive components,phenolic compounds,and antioxidant activities of Qingke compared with the effects of traditional roast(TR).Results showed that the soluble dietary fiber,beta-glucan and water-extractable pentosans of Qingke in dry heat processes of TR,SE,MB and FB had a higher content compared with other thermal methods and had a better antioxidant activity of hydroxyl radical scavenging and a better reduction capacity,while those in wet heat processes of BO and ST had a better antioxidant activity of ABTS radical scavenging and a better Fe2+ chelating ability.DF-and SE-Qingke had a higher content of tocopherol,phenolic,and flavonoid.Overall,6 free phenolic compounds and 12 bound phenolic compounds of Qingke were identified,and free phenolic compounds suffered more damage during thermal processing.Principal component analysis showed that SE had more advantages in retaining and improving the main biological active ingredients of Qingke,and it may be the best method for treating Qingke. 展开更多
关键词 Qingke(highland hull-less barley) Thermal processing Antioxidant activity Phenolic compounds Bioactive components
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Fresh-Cut Processing of Mulberry Branches and Assessment of Their Antioxidant Capacity 认领 引用
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作者 Xian CHEN Jing LI +5 位作者 Fujun CHEN Yongqi YE Siru XIE Yuxiang WEI Yulin HE Kaimei ZHU 《Medicinal Plant》 2026年第2期20-24,共5页
[Objectives]To optimize key fresh-cut technologies for mulberry branches by employing multiple evaluation indicators and to compare their antioxidant capacity with that of traditionally processed slices,thereby provid... [Objectives]To optimize key fresh-cut technologies for mulberry branches by employing multiple evaluation indicators and to compare their antioxidant capacity with that of traditionally processed slices,thereby providing guidance for the fresh-cut processing of mulberry branch medicinal materials.[Methods]A single-factor test method was employed to examine the effects of the drying degree of mulberry branches prior to cutting,cutting thickness,drying method,and drying temperature on the quality of slices.Evaluation indicators included appearance characteristics,alcohol extract content,total polysaccharide content,and total flavonol content,which were used to determine the optimal fresh-cut processing conditions.Additionally,the in vitro antioxidant activity of the samples was assessed using the DPPH free radical scavenging assay.[Results]The optimal parameters for fresh-cut processing of mulberry branches were identified as follows:A moisture content of(42±5)%prior to cutting,a slicing thickness of 4 mm,and hot air drying at 70℃.Slices produced under these conditions exhibited a smooth appearance,with relatively high levels of alcohol extract,total polysaccharides,and total flavonoids.Antioxidant activity assessment revealed that the IC 50 value of the fresh-cut processed slices against DPPH free radicals was 5.61 mg/mL,demonstrating superior efficacy compared to traditionally processed slices,which had an IC 50 value of 6.85 mg/mL.[Conclusions]The optimized fresh-cut process for mulberry branches is both reasonable and feasible,demonstrating high repeatability.This process significantly enhances the quality of slices and the retention of active components,and improves antioxidant activity,thereby offering a scientific foundation and practical guidance for the initial processing of mulberry branches at their source. 展开更多
关键词 Mulberry branches Fresh-cut processing Active component Quality evaluation
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Logistics Network Design for Manufacturing Enterprises with Component Processing Workshops 认领 引用
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作者 DING Yizhong 《Wuhan University Journal of Natural Sciences》 CAS 2010年第6期516-520,共5页
Logistics network design influences the efficiency and cost of Logistics directly.Some manufacturing enterprises not only have warehouse hubs,but also build component processing workshops which are usually located in ... Logistics network design influences the efficiency and cost of Logistics directly.Some manufacturing enterprises not only have warehouse hubs,but also build component processing workshops which are usually located in those places where the costs of materials and workforce are lower.This paper establishes a logistics network design model for the manufacturing enterprises with component processing workshops based on 0-1 mixture integer programming.The model optimizes the logistics network in an integrated view,by which the selection of the nodes,the manufacturing plan,and transportation plan can be obtained.An example is given to verify its feasibility.The approach is helpful for designing of the logistics network in manufacturing enterprises. 展开更多
关键词 manufacturing enterprise logistics network component processing 0-1 mixture integer programming
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Research Progress on Composition Changes, Pharmacological Effects and Food Processing Applications of Luo Han Guo Under the Control of Different Drying Technologies 认领 引用
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作者 Yanhong ZHAO Qingxin YU +3 位作者 Hui WEI Xuemei YAO Ke YANG Chunhui ZENG 《Medicinal Plant》 2026年第2期78-86,共9页
This paper summarizes the influence of different drying technologies on the appearance,taste,and chemical composition of Luo Han Guo.Building on its traditional efficacy of moistening the lungs and relieving cough as ... This paper summarizes the influence of different drying technologies on the appearance,taste,and chemical composition of Luo Han Guo.Building on its traditional efficacy of moistening the lungs and relieving cough as a starting point,and delves into the in-depth mechanism of its anti-inflammatory activity.Besides,it explores its antioxidant and hypoglycemic pharmacological properties,revealing the intrinsic correlation between its traditional efficacy and modern bioactivities.Modern drying technologies have enhanced the extraction efficiency of sweet-tasting and functional components in Luo Han Guo,expanding its development and application in modern food products.At present,there is a lack of studies on the differences in the efficacy of Luo Han Guo processed using various drying technology,and a significant gap exists in the research and development of its food-related applications.Therefore,this paper synthesizes the relevant research findings to provide a reference for the innovation of Luo Han Guo processing technologies and its future modern research and applications. 展开更多
关键词 Luo Han Guo(Siraitia grosvenorii(Swingle)C.Jeffrey) Drying technologies Active components Pharmacological action Food processing applications Food and medicine homology
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Polarimetric Meteorological Satellite Data Processing Software Classification Based on Principal Component Analysis and Improved K-Means Algorithm 认领 引用 被引量：2
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作者 Manyun Lin Xiangang Zhao +3 位作者 Cunqun Fan Lizi Xie Lan Wei Peng Guo 《Journal of Geoscience and Environment Protection》 2017年第7期39-48,共10页
With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In th... With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In this paper, a set of software classification method based on software operating characteristics is proposed. The method uses software run-time resource consumption to describe the software running characteristics. Firstly, principal component analysis (PCA) is used to reduce the dimension of software running feature data and to interpret software characteristic information. Then the modified K-means algorithm was used to classify the meteorological data processing software. Finally, it combined with the results of principal component analysis to explain the significance of various types of integrated software operating characteristics. And it is used as the basis for optimizing the allocation of software hardware resources and improving the efficiency of software operation. 展开更多
关键词 Principal Component Analysis Improved K-Mean Algorithm Meteorological Data Processing Feature Analysis Similarity Algorithm
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Multivariate Statistical Process Monitoring of an Industrial Polypropylene Catalyzer Reactor with Component Analysis and Kernel Density Estimation 认领 引用 被引量：16
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作者 熊丽 梁军 钱积新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 2007年第4期524-532,共9页
Abstract Data-driven tools, such as principal component analysis （PCA） and independent component analysis （ICA） have been applied to different benchmarks as process monitoring methods. The difference between the t... Abstract Data-driven tools, such as principal component analysis （PCA） and independent component analysis （ICA） have been applied to different benchmarks as process monitoring methods. The difference between the two methods is that the components of PCA are still dependent while ICA has no orthogonality constraint and its latentvariables are independent. Process monitoring with PCA often supposes that process data or principal components is Gaussian distribution. However, this kind of constraint cannot be satisfied by several practical processes. To ex-tend the use of PCA, a nonparametric method is added to PCA to overcome the difficulty, and kernel density estimation （KDE） is rather a good choice. Though ICA is based on non-Gaussian distribution intormation, .KDE can help in the close monitoring of the data. Methods, such as PCA, ICA, PCA.with .KDE（KPCA）, and ICA with KDE,（KICA）, are demonstrated and. compared by applying them to a practical industnal Spheripol craft polypropylene catalyzer reactor instead of a laboratory emulator. 展开更多
关键词 multivariate statistical process monitoring principal comPonent analysis kermel density estimation polypropylene catalyzer reactor fault detection data-driven tools
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Correlation Analysis of Processing Technology,Physical Parameters and Chemical Components during Plain Stir-baking of Trichosanthis Radix 认领 引用
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作者 Xinhong ZHAO Ruiying LI +3 位作者 Chao SUN Zhenhua LIU Xu XIAO Tianchao CHEN 《Medicinal Plant》 2021年第5期51-55,59,共5页
[Objectives]To explore the correlation of processing technology,physical parameters and chemical components during plain stir-baking of Trichosanthis Radix.[Methods]Based on mixture uniform experiment design,the Trich... [Objectives]To explore the correlation of processing technology,physical parameters and chemical components during plain stir-baking of Trichosanthis Radix.[Methods]Based on mixture uniform experiment design,the Trichosanthis Radix was prepared by plain stir-bake method.Delphi method was used to evaluate and select the highest-scoring processed product for measuring physical parameters.UV spectrophotometry was used to determine the contents of starch and polysaccharide.The correlation and linear regression model of processing technology,physical parameters and chemical components were established with the aid of SPSS 26.0[Results]After processing by plain stir-bake method,the relative density and chromaticity showed a decreasing trend in the processed products of Trichosanthis Radix,the oxidation value,hydroscopic rate and swelling decreased firstly and then increased,and pH increased firstly and then decreased.The content of total starch decreased,the content of polysaccharide increased,and there was a negative correlation between them.There was a significant positive correlation between temperature and oxidation value,swelling and hydroscopic rate,hydroscopic rate and polysaccharide,and there was a significant negative correlation between relative density and hydroscopic rate or polysaccharide,total starch and hydroscopic rate or swelling.The linear relation model between processing technology and physical parameters and chemical components was r2>0.9.[Conclusions]After processing by plain stir-bake method,the physical parameters of Trichosanthis Radix changed,and there may be mutual conversion between total starch and polysaccharides.To a certain extent,physical parameters can be used to evaluate the quality of processed products of Trichosanthis Radix.This study is expected to provide a reference for research on quality evaluation of processed products of traditional Chinese medicine. 展开更多
关键词 Trichosanthis Radix Processing technology Physical parameters Chemical components Correlation
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An Improved Adaptive Multi-way Principal Component Analysis for Monitoring Streptomycin Fermentation Process 认领 引用 被引量：11
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作者 何宁 王树青 谢磊 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 2004年第1期96-101,共6页
Multi-way principal component analysis (MPCA) had been successfully applied to monitoring the batch and semi-batch process in most chemical industry. An improved MPCA approach, step-by-step adaptive MPCA (SAMPCA), usi... Multi-way principal component analysis (MPCA) had been successfully applied to monitoring the batch and semi-batch process in most chemical industry. An improved MPCA approach, step-by-step adaptive MPCA (SAMPCA), using the process variable trajectories to monitoring the batch process is presented in this paper. It does not need to estimate or fill in the unknown part of the process variable trajectory deviation from the current time until the end. The approach is based on a MPCA method that processes the data in a sequential and adaptive manner. The adaptive rate is easily controlled through a forgetting factor that controls the weight of past data in a summation. This algorithm is used to evaluate the industrial streptomycin fermentation process data and is compared with the traditional MPCA. The results show that the method is more advantageous than MPCA, especially when monitoring multi-stage batch process where the latent vector structure can change at several points during the batch. 展开更多
关键词 step-by-step adaptive multi-way principal component analysis batch monitoring streptomycin fermentation static process monitoring
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Study on the Influence of Different Processing Methods on the Vola­tile Components of Alisma Purpurei 认领 引用
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作者 Weiwei Zhou Haiping Guo +2 位作者 Xiaoyu Cao Jie Liu Zhixuan Wang 《Journal of Advances in Medicine Science》 2024年第2期15-18,共4页
Objective:To establish a gas chromatography-mass spectrometry(GC-MS)method for the determination of volatile components in different prepared products of Alisma purpurea.Methods:The volatile components were determined... Objective:To establish a gas chromatography-mass spectrometry(GC-MS)method for the determination of volatile components in different prepared products of Alisma purpurea.Methods:The volatile components were determined by GC-MS,and the types and relative contents of volatile components were compared in 4 kinds of processed products.Result:The main volatile components of 30 kinds of different products from Zelica were analyzed and identified,which were mainly sesquiterpenes,ketones and alcohols,mainly Pogostol,olive,guaiacene,caryophyllene and so on.Conclusion:There are differences in the types and relative contents of volatile components in different products of Alisma platyphylla,in order to provide a basis for improving the quality standards of different products of Alisma platyphylla. 展开更多
关键词 Alisma alisma Processed products Gas chromatography-mass spectrometry Volatile components Relative content
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Statistical Monitoring of Chemical Processes Based on Sensitive Kernel Principal Components 认领 引用 被引量：10
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作者 JIANG Qingchao YAN Xuefeng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第6期633-643,共11页
The kernel principal component analysis(KPCA)method employs the first several kernel principal components(KPCs),which indicate the most variance information of normal observations for process monitoring,but may not re... The kernel principal component analysis(KPCA)method employs the first several kernel principal components(KPCs),which indicate the most variance information of normal observations for process monitoring,but may not reflect the fault information.In this study,sensitive kernel principal component analysis(SKPCA)is proposed to improve process monitoring performance,i.e.,to deal with the discordance of T2 statistic and squared prediction error SVE statistic and reduce missed detection rates.T2 statistic can be used to measure the variation di rectly along each KPC and analyze the detection performance as well as capture the most useful information in a process.With the calculation of the change rate of T2 statistic along each KPC,SKPCA selects the sensitive kernel principal components for process monitoring.A simulated simple system and Tennessee Eastman process are employed to demonstrate the efficiency of SKPCA on online monitoring.The results indicate that the monitoring performance is improved significantly. 展开更多
关键词 statistical process monitoring kernel principal component analysis sensitive kernel principal compo-nent Tennessee Eastman process
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Modified Multivariate Process Capability Index Using Principal Component Analysis 认领 引用 被引量：3
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作者 ZHANG Min WANG G Alan +1 位作者 HE Shuguang HE Zhen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期249-259,共11页
The existing research of process capability indices of multiple quality characteristics mainly focuses on nonconforming of process output,the concept development of tmivariate process capability indices,quality loss f... The existing research of process capability indices of multiple quality characteristics mainly focuses on nonconforming of process output,the concept development of tmivariate process capability indices,quality loss function and various comprehensive evaluation methods.The multivariate complexity increases the computation difficulty of multivariate process capability indices(MPCI),which makes them hard to be used in practice.In this paper,a new PCA-based MPCI approach is proposed to assess the production capability of the processes that involve multiple product quality characteristics.This approach first transforms the original quality variables into standardized normal variables.MPCI measures are then provided based on the Taam index.Moreover,the statistical properties of these MPCIs,such as confidence intervals and lower confidence bound,are given to let the practitioners understand the capability indices as random variables instead of deterministic variables.A real manufacturing data set and a synthetic data set are used to demonstrate the effectiveness of the proposed method.An implementation procedure is also provided for quality engineers to apply our MPCI approach in their manufacturing processes.The case studies demonstrate the effectiveness and feasibility of this new kind of MPCI,which is easier to be used in production practice.The proposed research provides a novel approach of MPCI calculation. 展开更多
关键词 process capability index multivariate specification region principal component analysis confidence interval
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Forming Laws and Processing Designing Methods for Multi-DOF Envelope Forming Process of Brake Pad Baseboard 认领 引用
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作者 Xinghui Han Wei Xiong +3 位作者 Wuhao Zhuang Lin Hua Fangyan Zheng Jingyu Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2025年第6期501-516,共16页
To improve braking performance and achieve lightweight in transport equipment,it is necessary to implement overall plastic forming manufacturing of the brake pad baseboard(BPB),which is the core safety component of th... To improve braking performance and achieve lightweight in transport equipment,it is necessary to implement overall plastic forming manufacturing of the brake pad baseboard(BPB),which is the core safety component of the brake system.This study presents an innovative multi-DOF envelope forming(MDFEF)process to realize the plastic forming of BPB with thin skin and high reinforcing ribs.The MDFEF principle for BPB,and the design methods for the envelope mold are first presented.Through FE simulations,the behavior of metal flow,uneven growth pattern of reinforcing ribs,evolution of equivalent strain and evolution of forming force in MDFEF of BPB are investigated.To realize MDFEF,an innovative MDFEF equipment driven by parallel linkages is exploited.The force states of linkages in MDFEF are calculated,and the reasonable mold position is determined to reduce the maximum force on the linkages and improve the service performance of MDFEF equipment.The MDFEF experiments of BPB are conducted and qualified BPB is obtained,which demonstrates that the presented MDFEF process and equipment are applicable to manufacture BPB with thin skin and high reinforcing ribs. 展开更多
关键词 Multi-DOF envelope forming Component with thin skin and reinforcing ribs Brake pad baseboard Forming laws Processing designing
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Improving the process forming limit considering forming defects in the transitional region in local loading forming of Ti-alloy rib-web components 认领 引用 被引量：5
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作者 Pengfei GAO Xiaodi LI +2 位作者 He YANG Xiaoguang FAN Zhenni LEI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第3期1270-1280,共11页
The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by... The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by forming defects in the transitional region.In this work,the feasibility of controlling forming defects and improving the process forming limit by adjusting die parameters is explored through finite element（FE） simulation.It is found that the common cavum and folding defects in the transitional region are significantly influenced by the fillet radii of left rib and middle rib,respectively.The cavum and folding defects can be effectively controlled by increasing the fillet radii of left rib and middle rib,respectively.The process forming limits considering forming defects in the transitional region are determined by the stepwise searching method under various die parameters.Moreover,the relationship between the process forming limit and die parameters is developed through the response surface methodology（RSM）.The developed RSM models suggest that increasing the fillet radii of left and middle ribs is effective to improve the process forming limit during local loading forming of rib-web components.The results will provide technical basis for the design of die parameters and the reduction amount,which is of great importance to control forming defects and improve the process forming limit in local loading forming of Ti-alloy large-scale rib-web components. 展开更多
关键词 Defect Large-scale rib-web component Local loading forming Process forming limit Transitional region
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A new process monitoring method based on noisy time structure independent component analysis 认领 引用 被引量：4
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作者 蔡连芳 田学民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期162-172,共11页
Conventional process monitoring method based on fast independent component analysis(Fast ICA) cannot take the ubiquitous measurement noises into account and may exhibit degraded monitoring performance under the advers... Conventional process monitoring method based on fast independent component analysis(Fast ICA) cannot take the ubiquitous measurement noises into account and may exhibit degraded monitoring performance under the adverse effects of the measurement noises. In this paper, a new process monitoring approach based on noisy time structure ICA(Noisy TSICA) is proposed to solve such problem. A Noisy TSICA algorithm which can consider the measurement noises explicitly is firstly developed to estimate the mixing matrix and extract the independent components(ICs). Subsequently, a monitoring statistic is built to detect process faults on the basis of the recursive kurtosis estimations of the dominant ICs. Lastly, a contribution plot for the monitoring statistic is constructed to identify the fault variables based on the sensitivity analysis. Simulation studies on the continuous stirred tank reactor system demonstrate that the proposed Noisy TSICA-based monitoring method outperforms the conventional Fast ICA-based monitoring method. 展开更多
关键词 Process monitoring Independent component analysis Measurement noises Kurtosis Mixing matrix Contribution plot Sensitivity analysis
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An aligned mixture probabilistic principal component analysis for fault detection of multimode chemical processes 认领 引用 被引量：8
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作者 杨雅伟 马玉鑫 +1 位作者 宋冰 侍洪波 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第8期1357-1363,共7页
A novel approach named aligned mixture probabilistic principal component analysis(AMPPCA) is proposed in this study for fault detection of multimode chemical processes. In order to exploit within-mode correlations,the... A novel approach named aligned mixture probabilistic principal component analysis(AMPPCA) is proposed in this study for fault detection of multimode chemical processes. In order to exploit within-mode correlations,the AMPPCA algorithm first estimates a statistical description for each operating mode by applying mixture probabilistic principal component analysis(MPPCA). As a comparison, the combined MPPCA is employed where monitoring results are softly integrated according to posterior probabilities of the test sample in each local model. For exploiting the cross-mode correlations, which may be useful but are inadvertently neglected due to separately held monitoring approaches, a global monitoring model is constructed by aligning all local models together. In this way, both within-mode and cross-mode correlations are preserved in this integrated space. Finally, the utility and feasibility of AMPPCA are demonstrated through a non-isothermal continuous stirred tank reactor and the TE benchmark process. 展开更多
关键词 Multimode process monitoring Mixture probabilistic principal component analysis Model alignment Fault detection
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Effects of granulation process variables on the physical properties of dosage forms by combination of experimental design and principal component analysis 认领 引用 被引量：1
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作者 Prakash Thapa Du Hyung Choi +1 位作者 Min Soo Kim Seong Hoon Jeong 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第3期287-304,共18页
The current study was to understand how process variables of high shear wet granulations affect physical properties of granules and tablets. The knowledge gained was intended to be used for Quality-by-Design based pro... The current study was to understand how process variables of high shear wet granulations affect physical properties of granules and tablets. The knowledge gained was intended to be used for Quality-by-Design based process design and optimization. The variables were selected based on the risk assessment as impeller speed, liquid addition rate, and wet massing time. Formulation compositions were kept constant to minimize their influence on granules properties. Multiple linear regression models were built providing understanding of the impact of each variable on granule hardness, Carr’s index, tablet tensile strength, surface mean diameter of granules, and compression behavior. The experimental results showed that the impact of impeller speed was more dominant compared to wet massing time and water addition rate. The results also revealed that quality of granules and tablets could be optimized by adjusting specific process variables(impeller speed 1193 rpm, water spray rate 3.7 ml/min, and wet massing time 2.84 min). Overall desirability was 0.84 suggesting that the response values were closer to the target one. The SEM image of granules showed that spherical and smooth granules produced at higher impeller speed, whereas rough and irregular shape granules at lower speed. Moreover, multivariate data analysis demonstrated that impeller speed and massing time had strong correlation with the granule and tablet properties. In overall, the combined experimental design and principal component analysis approach allowed to better understand the correlation between process variables and granules and tablet attributes. 展开更多
关键词 Experimental design Principal component analysis High shear granulation Process parameter
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Combination Method of Principal Component Analysis and Support Vector Machine for On-line Process Monitoring and Fault Diagnosis 认领 引用 被引量：2
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作者 赵旭 文香军 邵惠鹤 《Journal of Donghua University(English Edition)》 EI CAS 2006年第1期53-58,共6页
On-line monitoring and fault diagnosis of chemical process is extremely important for operation safety and product quality. Principal component analysis (PCA) has been widely used in multivariate statistical process m... On-line monitoring and fault diagnosis of chemical process is extremely important for operation safety and product quality. Principal component analysis (PCA) has been widely used in multivariate statistical process monitoring for its ability to reduce processes dimensions. PCA and other statistical techniques, however, have difficulties in differentiating faults correctly in complex chemical process. Support vector machine (SVM) is a novel approach based on statistical learning theory, which has emerged for feature identification and classification. In this paper, an integrated method is applied for process monitoring and fault diagnosis, which combines PCA for fault feature extraction and multiple SVMs for identification of different fault sources. This approach is verified and illustrated on the Tennessee Eastman benchmark process as a case study. Results show that the proposed PCA-SVMs method has good diagnosis capability and overall diagnosis correctness rate. 展开更多
关键词 principal component analysis multiple support vector machine process monitoring fault detection fault diagnosis.
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Application of Kernel Independent Component Analysis for Multivariate Statistical Process Monitoring 认领 引用 被引量：3
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作者 王丽 侍洪波 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期461-466,共6页
In this research, a new fault detection method based on kernel independent component analysis （kernel ICA） is developed. Kernel ICA is an improvement of independent component analysis （ICA）, and is different from ... In this research, a new fault detection method based on kernel independent component analysis （kernel ICA） is developed. Kernel ICA is an improvement of independent component analysis （ICA）, and is different from kernel principal component analysis （KPCA） proposed for nonlinear process monitoring. The basic idea of our approach is to use the kernel ICA to extract independent components efficiently and to combine the selected essential independent components with process monitoring techniques. 12 （the sum of the squared independent scores） and squared prediction error （SPE） charts are adopted as statistical quantities. The proposed monitoring method is applied to Tennessee Eastman process, and the simulation results clearly show the advantages of kernel ICA monitoring in comparison to ICA monitoring. 展开更多
关键词 process monitoring fault detection kernelindependent component analysis
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