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The bio-active components of the Mongolian medicine Horcha-6 and therapeutic mechanism in the rat migraine model
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作者 Ao Qier Naren Mandula +7 位作者 Qiburi Qiburi Manda Manda Tegexi Baiyin Xilinqiqige Bao Huricha Baigued Chang-Shan Wang Temuqile Temuqile De-Zhi Yang 《Traditional Medicine Research》 2024年第2期8-17,共10页
Background:The active components of Horcha-6 were identified using liquid chromatography with tandem mass spectrometry.Also,we investigated the potential mechanisms that explain why Horcha-6 may be effective in treati... Background:The active components of Horcha-6 were identified using liquid chromatography with tandem mass spectrometry.Also,we investigated the potential mechanisms that explain why Horcha-6 may be effective in treating migraines through the use of network pharmacology and a rat migraine model.Methods:After identifying the active components of Horcha-6,the corresponding genes of the active components’target were obtained from the Universal Protein database,and a“compound-target-disease”network was constructed using Cytoscape 3.9.0 software.For the in vivo experiments,nitroglycerin was injected intraperitoneally into rats to create a migraine model.Pre-treatment with Horcha-6 was administered orally for 14 days,and rats were subjected to migraine-related behavior tests.RNA sequencing was performed to identify the gene expression regulated by Horcha-6 in the trigeminal nerve.Results:A total of 903 chemical components of Horcha-6 have been collected in the liquid chromatography with tandem mass spectrometry.We discovered 55 of the Horcha-6 bio-active components that were evaluated based on their Percent Human Oral Absorption(≥30%)and DL values(≥0.185)on the traditional Chinese medicine systems pharmacology database.The“compound-target-disease”network contained 163 intersection targets with the migraine state.Gene Ontology analysis indicated that these components significantly regulated the immune response,vascular function,oxidative stress,etc.When Kyoto Encyclopedia of Genes and Genomes enrichment analysis was performed,we observed that most of the target genes were significantly enriched in the inflammation and neuro-related signaling pathway,toll-like receptor signaling pathway,neuroactive ligand-receptor interaction,etc.These predictions were further demonstrated via in vivo animal model experiments.The RNA sequencing results showed that 41 genes were down-regulated(P<0.05)and 86 genes were up-regulated(P<0.05)in the Horcha-6 treated group compared with the untreated group.Those genes were mainly involved in neuromodulation,vascular function,and hormone metabolism.Conclusion:The 55 bio-active components in Horcha-6 regulate inflammation,hormone metabolism,and neurotransmitters and have potential as a therapy to treat migraines. 展开更多
关键词 Horcha-6 bio-active components rat migraine model inflammation hormone metabolism NEUROTRANSMITTER
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A new production component method for natural gas development planning
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作者 Fanliao Wang Jiangchen Han +4 位作者 Shucheng Liu Yanqing Liu Kun Su Jing Du Liru Wang 《Energy Geoscience》 EI 2024年第1期283-292,共10页
Based on an analysis of the limitations of conventional production component methods for natural gas development planning,this study proposes a new one that uses life cycle models for the trend fitting and prediction ... Based on an analysis of the limitations of conventional production component methods for natural gas development planning,this study proposes a new one that uses life cycle models for the trend fitting and prediction of production.In this new method,the annual production of old and new wells is predicted by year first and then is summed up to yield the production for the planning period.It shows that the changes in the production of old wells in old blocks can be fitted and predicted using the vapor pressure model(VPM),with precision of 80%e95%,which is 6.6%e13.2%higher than that of other life cycle models.Furthermore,a new production prediction process and method for new wells have been established based on this life cycle model to predict the production of medium-to-shallow gas reservoirs in western Sichuan Basin,with predication error of production rate in 2021 and 2022 being 6%and 3%respectively.The new method can be used to guide the medium-and long-term planning or annual scheme preparation for gas development.It is also applicable to planning for large single gas blocks that require continuous infill drilling and adjustment to improve gas recovery. 展开更多
关键词 Production component method Production prediction Life cycle model Gas development planning Western Sichuan Basin
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A blast furnace fault monitoring algorithm with low false alarm rate:Ensemble of greedy dynamic principal component analysis-Gaussian mixture model 被引量:1
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作者 Xiongzhuo Zhu Dali Gao +1 位作者 Chong Yang Chunjie Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期151-161,共11页
The large blast furnace is essential equipment in the process of iron and steel manufacturing. Due to the complex operation process and frequent fluctuations of variables, conventional monitoring methods often bring f... The large blast furnace is essential equipment in the process of iron and steel manufacturing. Due to the complex operation process and frequent fluctuations of variables, conventional monitoring methods often bring false alarms. To address the above problem, an ensemble of greedy dynamic principal component analysis-Gaussian mixture model(EGDPCA-GMM) is proposed in this paper. First, PCA-GMM is introduced to deal with the collinearity and the non-Gaussian distribution of blast furnace data.Second, in order to explain the dynamics of data, the greedy algorithm is used to determine the extended variables and their corresponding time lags, so as to avoid introducing unnecessary noise. Then the bagging ensemble is adopted to cooperate with greedy extension to eliminate the randomness brought by the greedy algorithm and further reduce the false alarm rate(FAR) of monitoring results. Finally, the algorithm is applied to the blast furnace of a large iron and steel group in South China to verify performance.Compared with the basic algorithms, the proposed method achieves lowest FAR, while keeping missed alarm rate(MAR) remain stable. 展开更多
关键词 Chemical processes Principal component analysis Gaussian mixture model Process monitoring ENSEMBLE Process control
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Applications of Computer Aided Modeling Techniques to Complex ICE Components 被引量:1
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作者 左正兴 冯慧华 +1 位作者 廖日东 邹文胜 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期451-458,共8页
Design of internal combustion engine (ICE) components is one of the earliest and also the most active areas in which computer aided modeling techniques are applied. Computer aided modeling techniques could provide req... Design of internal combustion engine (ICE) components is one of the earliest and also the most active areas in which computer aided modeling techniques are applied. Computer aided modeling techniques could provide requisite information for follow up designing segments such as structural analysis, design of technological process and manufacturing etc, and thereby lead to the reduction of product design period and the quality and reliability improvement of ICE components. So the developing situations of ICE components' 2 D drafting, 3 D modeling of ICE, overall CAD of ICE as well as component design expert system etc. are surveyed, which are the typical applications of computer aided modeling techniques in ICE component design process, and some existent problems and tasks are pointed out so as to make some references for the further research work. 展开更多
关键词 internal combustion engine(ICE) components computer aided modeling CAD 3 D model
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Disassemblability Modeling Technology of Configurable Product Based on Disassembly Constraint Relation Weighted Design Structure Matrix(DSM) 被引量:3
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作者 QIU Lemiao LIU Xiaojian +1 位作者 ZHANG Shuyou SUN Liangfeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第3期511-519,共9页
The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disa... The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disassemblability. The disassemblability modeling technology for configurable product based on disassembly constraint relation weighted design structure matrix (DSM) is proposed. Major factors affecting the disassemblability of configurable product are analyzed, and the disassembling degrees between components in configurable product are obtained by calculating disassembly entropies such as joint type, joint quantity, disassembly path, disassembly accessibility and material compatibility. The disassembly constraint relation weighted DSM of configurable product is constructed and configuration modules are formed by matrix decomposition and tearing operations. The disassembly constraint relation in configuration modules is strong coupling, and the disassembly constraint relation between modules is weak coupling, and the disassemblability configuration model is constructed based on configuration module. Finally, taking a hydraulic forging press as an example, the decomposed weak coupling components are used as configuration modules alone, components with a strong coupling are aggregated into configuration modules, and the disassembly sequence of components inside configuration modules is optimized by tearing operation. A disassemblability configuration model of the hydraulic forging press is constructed. By researching the disassemblability modeling technology of product configuration design based on disassembly constraint relation weighted DSM, the disassembly property in maintenance, recycling and reuse of configurable product are optimized. 展开更多
关键词 disassemblability modeling disassembly entropy disassembling degree weighted DSM product configuration model
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EMPIRICAL BAYES TEST PROBLEMS OF VARIANCE COMPONENTS IN RANDOM EFFECTS MODEL 被引量:3
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作者 韦来生 张伟平 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期274-282,共9页
Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that t... Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that the proposed EB decision rules are asymptotically optimal with convergence rates near O(n-1/2). Finally, an example concerning the main result is given. 展开更多
关键词 Empirical Bayes test variance components random effects model convergence rates
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U-Net Models for Representing Wind Stress Anomalies over the Tropical Pacific and Their Integrations with an Intermediate Coupled Model for ENSO Studies 被引量:1
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作者 Shuangying Du Rong-Hua Zhang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1403-1416,共14页
El Niño-Southern Oscillation(ENSO)is the strongest interannual climate mode influencing the coupled ocean-atmosphere system in the tropical Pacific,and numerous dynamical and statistical models have been develope... El Niño-Southern Oscillation(ENSO)is the strongest interannual climate mode influencing the coupled ocean-atmosphere system in the tropical Pacific,and numerous dynamical and statistical models have been developed to simulate and predict it.In some simplified coupled ocean-atmosphere models,the relationship between sea surface temperature(SST)anomalies and wind stress(τ)anomalies can be constructed by statistical methods,such as singular value decomposition(SVD).In recent years,the applications of artificial intelligence(AI)to climate modeling have shown promising prospects,and the integrations of AI-based models with dynamical models are active areas of research.This study constructs U-Net models for representing the relationship between SSTAs andτanomalies in the tropical Pacific;the UNet-derivedτmodel,denoted asτUNet,is then used to replace the original SVD-basedτmodel of an intermediate coupled model(ICM),forming a newly AI-integrated ICM,referred to as ICM-UNet.The simulation results obtained from ICM-UNet demonstrate their ability to represent the spatiotemporal variability of oceanic and atmospheric anomaly fields in the equatorial Pacific.In the ocean-only case study,theτUNet-derived wind stress anomaly fields are used to force the ocean component of the ICM,the results of which also indicate reasonable simulations of typical ENSO events.These results demonstrate the feasibility of integrating an AI-derived model with a physics-based dynamical model for ENSO modeling studies.Furthermore,the successful integration of the dynamical ocean models with the AI-based atmospheric wind model provides a novel approach to ocean-atmosphere interaction modeling studies. 展开更多
关键词 U-Net models wind stress anomalies ICM integration of AI and physical components
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SOFTWARE RELIABILITY MODEL FOR COMPONENT INTERACTION MODE 被引量:2
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作者 Wang Qiang Lu Yang +1 位作者 Xu Zijun Han Jianghong 《Journal of Electronics(China)》 2011年第4期632-642,共11页
With the rapid progress of component technology,the software development methodology of gathering a large number of components for designing complex software systems has matured.But,how to assess the application relia... With the rapid progress of component technology,the software development methodology of gathering a large number of components for designing complex software systems has matured.But,how to assess the application reliability accurately with the information of system architecture and the components reliabilities together has become a knotty problem.In this paper,the defects in formal description of software architecture and the limitations in existed model assumptions are both analyzed.Moreover,a new software reliability model called Component Interaction Mode(CIM) is proposed.With this model,the problem for existed component-based software reliability analysis models that cannot deal with the cases of component interaction with non-failure independent and non-random control transition is resolved.At last,the practice examples are presented to illustrate the effectiveness of this model. 展开更多
关键词 component CONNECTOR Software architecture Reliability model
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Local component based principal component analysis model for multimode process monitoring 被引量:5
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作者 Yuan Li Dongsheng Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第6期116-124,共9页
For plant-wide processes with multiple operating conditions,the multimode feature imposes some challenges to conventional monitoring techniques.Hence,to solve this problem,this paper provides a novel local component b... For plant-wide processes with multiple operating conditions,the multimode feature imposes some challenges to conventional monitoring techniques.Hence,to solve this problem,this paper provides a novel local component based principal component analysis(LCPCA)approach for monitoring the status of a multimode process.In LCPCA,the process prior knowledge of mode division is not required and it purely based on the process data.Firstly,LCPCA divides the processes data into multiple local components using finite Gaussian mixture model mixture(FGMM).Then,calculating the posterior probability is applied to determine each sample belonging to which local component.After that,the local component information(such as mean and standard deviation)is used to standardize each sample of local component.Finally,the standardized samples of each local component are combined to train PCA monitoring model.Based on the PCA monitoring model,two monitoring statistics T^(2) and SPE are used for monitoring multimode processes.Through a numerical example and the Tennessee Eastman(TE)process,the monitoring result demonstrates that LCPCA outperformed conventional PCA and LNS-PCA in the fault detection rate. 展开更多
关键词 Principal component analysis Finite Gaussian mixture model Process monitoring Tennessee Eastman(TE)process
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Leakage Rate Model of Urban Water Supply Networks Using Principal Component Regression Analysis 被引量:1
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作者 Zhiguang Niu Chong Wang +2 位作者 Ying Zhang Xiaoting Wei Xili Gao 《Transactions of Tianjin University》 EI CAS 2018年第2期172-181,共10页
To analyze the factors affecting the leakage rate of water distribution system, we built a macroscopic "leakage rate–leakage factors"(LRLF) model. In this model, we consider the pipe attributes(quality, dia... To analyze the factors affecting the leakage rate of water distribution system, we built a macroscopic "leakage rate–leakage factors"(LRLF) model. In this model, we consider the pipe attributes(quality, diameter,age), maintenance cost, valve replacement cost, and annual average pressure. Based on variable selection and principal component analysis results, we extracted three main principle components—the pipe attribute principal component(PAPC), operation management principal component, and water pressure principal component. Of these, we found PAPC to have the most influence. Using principal component regression, we established an LRLF model with no detectable serial correlations. The adjusted R2 and RMSE values of the model were 0.717 and 2.067, respectively.This model represents a potentially useful tool for controlling leakage rate from the macroscopic viewpoint. 展开更多
关键词 Water DISTRIBUTION system LEAKAGE RATE LEAKAGE influencing FACTOR QUANTITATIVE model Principal component regression
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Evaluation of Component Activities in C-Mn-Fe-Si with Model Self-SReM4 被引量:1
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作者 Zhang Xiaobing Jiang Guochang +1 位作者 Ding Weizhong Xu Kuangdi 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1998年第1期28-33,共6页
A sub-regular solution model SELFSReM4 used to evaluate activities of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Lab of Ferrometallurgy. This paper introduces... A sub-regular solution model SELFSReM4 used to evaluate activities of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Lab of Ferrometallurgy. This paper introduces the application of SELFSReM4 in evaluating activities of the components in C-Mn-Fe-Si system without SiC precipitation. 展开更多
关键词 sub-regular solution model component activity C-Mn-Si-Fe alloy
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Predicting configuration performance of modular product family using principal component analysis and support vector machine 被引量:1
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作者 张萌 李国喜 +1 位作者 龚京忠 吴宝中 《Journal of Central South University》 SCIE EI CAS 2014年第7期2701-2711,共11页
A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a n... A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a newly configured product through soft computing technique instead of practical test experiments,which helps to evaluate whether or not the product variant can satisfy the customers' individual requirements.The PCA technique was used to reduce and orthogonalize the module parameters that affect the product performance.Then,these extracted features were used as new input variables in SVM model to mine knowledge from the limited existing product data.The performance values of a newly configured product can be predicted by means of the trained SVM models.This PCA-SVM method can ensure that the performance prediction is executed rapidly and accurately,even under the small sample conditions.The applicability of the proposed method was verified on a family of plate electrostatic precipitators. 展开更多
关键词 design configuration performance prediction MODULARITY principal component analysis support vector machine
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Evaluation of Component Activity in Molten MnO-SiO_(2)-Al_(2)O_(3)-CaO System with Model SELF-SReM4 被引量:1
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作者 ZHANG Xiao-bing JIANG Guo-chang XU Kuang-di 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2000年第1期6-8,共3页
A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of Ferrometallurgy.The application ... A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of Ferrometallurgy.The application of SELF-SReM4 in C-Mn-Fe-Si system without the SiC formation has been introduced in previous paper.It’s application for molten slag of MnO-SiO2-Al2O3-CaO was introduced in this paper.They provide a basis for the prediction of the metal-slag equilibrium conditions. 展开更多
关键词 sub-regular solution model component activity m olten slag MnO-SiO2-Al2O3-CaO
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Organization-Driven Business Process Configurable Modeling for Spatial Variability 被引量:1
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作者 Guosheng Kang Liqing Yang +2 位作者 Liang Zhang Jianxun Liu Yiping Wen 《China Communications》 SCIE CSCD 2021年第11期229-242,共14页
Nowadays,enterprises need to continually adjust their business processes to adapt to the changes of business environments,especially when one business needs to be deployed in different application scenarios,which is c... Nowadays,enterprises need to continually adjust their business processes to adapt to the changes of business environments,especially when one business needs to be deployed in different application scenarios,which is called spatial variability in this paper.In the field of BPM(Business Process Management),configurable business process models have demonstrated their effectiveness in aspects of process modeling and model reuse.Yet,we found that the existing techniques lead to complex configurable models,and are inadequate for model reuse especially for the spatial variability issue because they neglect the root impact of organizations on control flow.S-BPM(Subject-oriented Business Process Management)models provide a solid foundation for dealing with complex applications and help to bridge the gap between business and IT for process execution.In this paper,we propose an organization-driven business process configurable modeling approach for spatial variability by integrating both restriction and extension operations based on the S-BPM paradigm,in which business objects are also included.Our approach is validated with a general business process developed for the Real Estate Administration(REA)in a certain province of China.The resulting configurable modeling framework can express the heterogeneous activity sequences for one business and has the potential to generate process models for uncertain environments in a new organization structure. 展开更多
关键词 S-BPM configurable modeling organization-driven spatial variability business objects services
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Nonlinear total least-squares variance component estimation for GM(1,1)model 被引量:2
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作者 Leyang Wang Jianqiang Sun Qiwen Wu 《Geodesy and Geodynamics》 CSCD 2021年第3期211-217,共7页
The solution of the grey model(GM(1,1)model)generally involves equal-precision observations,and the(co)variance matrix is established from the prior information.However,the data are generally available with unequal-pr... The solution of the grey model(GM(1,1)model)generally involves equal-precision observations,and the(co)variance matrix is established from the prior information.However,the data are generally available with unequal-precision measurements in reality.To deal with the errors of all observations for GM(1,1)model with errors-in-variables(EIV)structure,we exploit the total least-squares(TLS)algorithm to estimate the parameters of GM(1,1)model in this paper.Ignoring that the effect of the improper prior stochastic model and the homologous observations may degrade the accuracy of parameter estimation,we further present a nonlinear total least-squares variance component estimation approach for GM(1,1)model,which resorts to the minimum norm quadratic unbiased estimation(MINQUE).The practical and simulative experiments indicate that the presented approach has significant merits in improving the predictive accuracy in comparison with control methods. 展开更多
关键词 GM(1 1)model Minimum norm quadratic unbiased estimation(MINQUE) Total least-squares(TLS) Unequal-precision measurement Variance component estimation(VCE)
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Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model 被引量:4
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作者 张伟伟 宋晓琳 张桂香 《Journal of Central South University》 SCIE EI CAS 2014年第4期1633-1642,共10页
A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and... A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning. 展开更多
关键词 lane departure warning system lane detection lane tracking principal component analysis risk evaluation model ARM-based real-time system
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Application of synthetic principal component analysis model to mine area farmland heavy metal pollution assessment 被引量:1
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作者 王从陆 吴超 王卫军 《Journal of Coal Science & Engineering(China)》 2008年第1期109-113,共5页
Referring to GB5618-1995 about heavy metal pollution,and using statistical analysis SPSS,the major pollutants of mine area farmland heavy metal pollution were identified by variable clustering analysis.Assessment and ... Referring to GB5618-1995 about heavy metal pollution,and using statistical analysis SPSS,the major pollutants of mine area farmland heavy metal pollution were identified by variable clustering analysis.Assessment and classification were done to the mine area farmland heavy metal pollution situation by synthetic principal components analysis (PCA).The results show that variable clustering analysis is efficient to identify the principal components of mine area farmland heavy metal pollution.Sort and clustering were done to the synthetic principal components scores of soil sample,which is given by synthetic principal components analysis.Data structure of soil heavy metal contaminations relationships and pollution level of different soil samples are discovered.The results of mine area farmland heavy metal pollution quality assessed and classified with synthetic component scores reflect the influence of both the major and compound heavy metal pol- lutants.Identification and assessment results of mine area farmland heavy metal pollution can provide reference and guide to propose control measures of mine area farmland heavy metal pollution and focus on the key treatment region. 展开更多
关键词 synthetic principal components analysis model heavy metal pollution mineregional soils
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Reconfigurable Modeling Technology of Similar-structure Products Configuration Design
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作者 QIU Lemiao REN Bin +1 位作者 ZHANG Shuyou XU Jian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期189-196,共8页
The product configuration modeling is a key technology to realize configuration design. Most of the researches were mainly conducted focusing on how to establish a product configuration model, but were short of the co... The product configuration modeling is a key technology to realize configuration design. Most of the researches were mainly conducted focusing on how to establish a product configuration model, but were short of the consideration about the application scope and dynamic change features. In this paper, the reconfigurable modeling technology of similar-structure products configuration design is studied to enhance the generality and diversity of product configuration models, and to facilitate the dynamic upgrade of configuration models. The configuration components of products with similar structures are divided into sharable configuration components, essential configuration components and optional configuration components, so the construction of reconfigurable model of configuration design can be converted into the set operation of configuration components. The horizontal adjusting reconstruction of configuration model is carried out through the adding, replacing and deleting of configuration components, the vertical adjusting reconstruction of configuration model is carried out through the parametric deformation of configuration components, and the variable topological configuration model reconstruction can be realized through the transformation of partial structure of configuration components. Finally, NC machine products are used as an example to analyze and verify the reconfigurable modeling technology of products with similar structures. The speed of NC machine configuration design is found to be improved, and the number of NC machine configuration design models is decreased. And the reconfigurable design system of NC machine products is developed. The proposed modeling technology provides references for the processes, methods and steps of model reconstruction. 展开更多
关键词 similar-structure products configuration component product configuration model RECONSTRUCTION
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Configurable Product Design Considering the Transition of Multi-hierarchical Models
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作者 REN Bin QIU Lemiao +2 位作者 ZHANG Shuyou TAN Jianrong CHENG Jin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期217-224,共8页
The current research of configurable product design mainly focuses on how to convert a predefined set of components into a valid set of product structures. With the scale and complexity of configurable products increa... The current research of configurable product design mainly focuses on how to convert a predefined set of components into a valid set of product structures. With the scale and complexity of configurable products increasing, the interdependencies between customer demands and product structures grow up as well. The result is that existing product structures fails to satisfy the individual customer requirements and hence product variants are needed. This paper is aimed to build a bridge between customer demands and product structures in order to make demand-driven fast response design feasible. First of all, multi-hierarchical models of configurable product design are established with customer demand model, technical requirement model and product structure model. Then, the transition of multi-hierarchical models among customer demand model, technical requirement model and product structure model is solved with fuzzy analytic hierarchy process (FAHP) and the algorithm of multi-level matching. Finally, optimal structure according to the customer demands is obtained with the calculation of Euclidean distance and similarity of some cases. In practice, the configuration design of a clamping unit of injection molding machine successfully performs an optimal search strategy for the product variants with reasonable satisfaction to individual customer demands. The proposed method can automatically generate a configuration design with better alternatives for each product structures, and shorten the time of finding the configuration of a product. 展开更多
关键词 configuration design optimal strategy variant design multi-hierarchical models
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Fault diagnosis method for an Aeroengine Based on Independent Component Analysis and the Discrete Hidden Markov Model 被引量:1
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作者 MA Jian-cang ZENG Yuan 《International Journal of Plant Engineering and Management》 2009年第4期193-201,共9页
The vibration signals of an aeroengine are a very important information source for fault diagnosis and condition monitoring. Considering the nonstationarity and low repeatability of the vibration signals, it is necess... The vibration signals of an aeroengine are a very important information source for fault diagnosis and condition monitoring. Considering the nonstationarity and low repeatability of the vibration signals, it is necessary to find a corresponding method for feature extraction and fault recognition. In this paper, based on Independent Component Analysis (ICA) and the Discrete Hidden Markov Model (DHMM), a new fault diagnosis approach named ICA-DHMM is proposed. In this method, ICA separates the source signals from the mixed vibration signals and then extracts features from them, DHMM works as a classifier to recognize the conditions of the aeroengine. Compared with the DHMM, which use the amplitude spectrum of mixed signals as feature parameters, experimental results show this method has higher diagnosis accuracy. 展开更多
关键词 independent component analysis (ICA) feature extraction discrete hidden Markov model DHMM) AEROENGINE fault diagnosis
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