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A Modified Principal Component Analysis Method for Honeycomb Sandwich Panel Debonding Recognition Based on Distributed Optical Fiber Sensing Signals
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作者 Shuai Chen Yinwei Ma +5 位作者 Zhongshu Wang Zongmei Xu Song Zhang Jianle Li Hao Xu Zhanjun Wu 《Structural Durability & Health Monitoring》 EI 2024年第2期125-141,共17页
The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scatt... The safety and integrity requirements of aerospace composite structures necessitate real-time health monitoring throughout their service life.To this end,distributed optical fiber sensors utilizing back Rayleigh scattering have been extensively deployed in structural health monitoring due to their advantages,such as lightweight and ease of embedding.However,identifying the precise location of damage from the optical fiber signals remains a critical challenge.In this paper,a novel approach which namely Modified Sliding Window Principal Component Analysis(MSWPCA)was proposed to facilitate automatic damage identification and localization via distributed optical fiber sensors.The proposed method is able to extract signal characteristics interfered by measurement noise to improve the accuracy of damage detection.Specifically,we applied the MSWPCA method to monitor and analyze the debonding propagation process in honeycomb sandwich panel structures.Our findings demonstrate that the training model exhibits high precision in detecting the location and size of honeycomb debonding,thereby facilitating reliable and efficient online assessment of the structural health state. 展开更多
关键词 Structural health monitoring distributed opticalfiber sensor damage identification honeycomb sandwich panel principal component analysis
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DISTRIBUTED SIMULATION SYSTEM BASED ON UNIVERSAL COMPONENTS
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作者 孙知信 王汝传 王绍棣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期69-75,共7页
Based on MATRIXx, a universal real-time visual distributed simulation system is developed. The system can receive different input data from network or local terminal. Application models in the simulation modules can a... Based on MATRIXx, a universal real-time visual distributed simulation system is developed. The system can receive different input data from network or local terminal. Application models in the simulation modules can automatically get such data to be analyzed and calculated, and then produce real-time simulation control information. Meanwhile, this paper designs relevant simulation components to implement the input and output data, which can guarantee the real-time and universal of the data transmission. Result of the experimental system shows that the real-time performance of the simulation is perfect. 展开更多
关键词 distributed simulation data collection universal component
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Distribution, Development and Utilization of Bioactive Components Resources of Russian Melilotus officinalis
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作者 林年丰 梁硕 《Agricultural Science & Technology》 CAS 2017年第12期2312-2316,2319,共6页
To confirm the content and distribution of bioactive components in roots, stems, leaves and grains of Russian Me/i/otus officina/is 'Sligen 1 ", an experiment involving bioactive components detection and field plant... To confirm the content and distribution of bioactive components in roots, stems, leaves and grains of Russian Me/i/otus officina/is 'Sligen 1 ", an experiment involving bioactive components detection and field planting was conducted. Kjeldahl method and high performance gas chromatography were used to detect the protein. The automatic amino acid analyzer was used to detect amino acid. Gas chromatography-mass spectrometry (GC-MS) and molecular distillation apparatus were used to confirm the fatty acid content. Gravimetric method was used to detect saponin and alkaloid contents. High performance liquid chromatography was used to detect the coumarin content. The polyphenol content was determined by forint reagent colorimetric method. Anthracene copper-sulfuric acid colorimetry was used to detect the polysaccharide, and aluminum nitrate-sodium nitrite-sodium hydroxide col- orimetric method was used to confirm flavone. The results showed that protein and amino acid were mainly distributed in leaves and seeds. The fatty acid was mainly distributed in seeds. The saponin was mainly distributed in roots and leave. The polyphenol was mainly distributed in roots, stems and leaves. The alkaloid was mainly distributed in stems, leaves and seeds. Seeds mainly contained coumarin. M. officinalis had little polysaccharide and flavone. The total production of bioactive in- gredients was 3 016.3 kg/hm2. The output of crude protein, amino acids and fatty acids was 1 400.6, 1 246.8, 112.2, respectively. The yields of effective components saponins, alkaloids, polyphenols and coumarin were 97.0, 77.9, 41.7, 40.1 kg/hm2, respectively. After separation, extraction and purification, those components can be used as the natural ingredients to develop medicine, food, chemical and other biotechnological products. 展开更多
关键词 Melilotus officinalis Bioactive component distribution characteristics De-velopment and utilization
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Effects of the Component and Fiber Gradient Distributions on the Strength of Cement-based Composite Materials 被引量:8
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作者 杨久俊 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第2期61-64,共4页
The effects of the component gradient distribution at interface and the fiber gradient distribution on the strength of cement-based materials were studied. The results show that the flexural strength and compressive s... The effects of the component gradient distribution at interface and the fiber gradient distribution on the strength of cement-based materials were studied. The results show that the flexural strength and compressive strength of the mortar and concrete with interface component and fiber gradient distributions are obviously improved. The strengthes of the fiber gradient distributed mortar and concrete (FGDM/C) are higher than those of fiber homogeneously distributed mortar and concrete (FHDM/C). To obtain the same strength, therefore, a smaller fiber volume content in FGDM/C is needed than that in FHDM/C. The results also show that the component gradient distribution of the concrete can be obtained by means of multi-layer vibrating formation. 展开更多
关键词 component gradient distribution fiber gradient distribution cement-based functional materials
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Some phenomena and features of the component distributions in welding arc 被引量:1
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作者 Song Yonglun (South China University of Technology, Guangzhou) 《China Welding》 EI CAS 1995年第1期65-69,共5页
The components and their distributions both in space and in time are observed by spectroscopic method under GMAW and GTAW conditions.It reveals the features of component distributions in the arc as well as their regul... The components and their distributions both in space and in time are observed by spectroscopic method under GMAW and GTAW conditions.It reveals the features of component distributions in the arc as well as their regularities,and may lead to an essential knowledge to understand some physical and chemical phenomena in arc welding processes. 展开更多
关键词 component distribution welding arc SENSOR
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Investigation on the factors influencing the thickness distribution of superplastic-formed components 被引量:1
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作者 高重阳 方攸同 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期711-715,共5页
In the superplastic sheet forming process, the uniformity of the sheet's final thickness distribution is vital for ensuring the good mechanical quality of the formed components. The influences of the component sha... In the superplastic sheet forming process, the uniformity of the sheet's final thickness distribution is vital for ensuring the good mechanical quality of the formed components. The influences of the component shape and the contact friction on the final thickness distribution were investigated in this work by using finite element method on a series of axisymmetric models. It was concluded that shape optimization and friction elimination are required to get uniform thickness distribution, and eventually to improve the mechanical quality of the formed components. The constitutive equation of the Ti-6A1-4V superplastic material was also determined on the basis of experimental data. 展开更多
关键词 Thickness distribution component shape Contact friction SPF TI-6A1-4V
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Binary-component micelle and vesicle:Free energy and asymmetric distributions of amphiphiles between vesicle monolayers
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作者 张启义 向洵 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期517-521,共5页
The real-space two-dimensional self-consistent field theory(SCFT) is employed to study the free energies of micelles and vesicles constituted by binary amphiphilic diblock copolymer AB in homopolymer A.With an incre... The real-space two-dimensional self-consistent field theory(SCFT) is employed to study the free energies of micelles and vesicles constituted by binary amphiphilic diblock copolymer AB in homopolymer A.With an increasing volume fraction of copolymer AB,there are morphological transitions from circle micelles to oblate circle-like micelles,to a compound structure with inverted micelles in the inner center and micelles outer layer,and to vesicles.Special attention is paid to the role of the copolymer AB in controlling the free energies of the micelles and vesicles by examining the effect of the length ratio of A/B with the fixed whole chain length of the AB copolymer,the length effect of A or B block with the corresponding fixed length of B or A block,for one component of copolymer,and the effect of different amphiphile compositions for a binary-component copolymer system.The quantity η is provided to describe the asymmetric density distribution of amphiphiles between the inner and outer monolayers of vesicles,and to quantify the relative asymmetric extent of the density distribution between two species of copolymers in binary component vesicles. 展开更多
关键词 binary components VESICLE MICELLE asymmetry distribution
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Population distribution in China-characteristics,components, determinants since 1949
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作者 MENG Xiang-jing JIA Shao-fen (People’s University of Chin4 Beijing 100872, China, InstitUte of Geography, Chinese Academy of Sciences, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第2期123-134,共12页
Rational population distribution is an important issue in China. In depth analysis on population distribution is valuable for policy making. in this paper, an attempt is made to study changes in population distributio... Rational population distribution is an important issue in China. In depth analysis on population distribution is valuable for policy making. in this paper, an attempt is made to study changes in population distribution by region. province, rural-urban and city size in China. their components and determinants since 1949. 展开更多
关键词 China popultion distribution CHARACTERISTICS components determinants
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The Changing Characteristics of Profile Distribution of Organic Nitrogen Components in Apple-pear Orchard Soil
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作者 Huan LIU Qian GAO +4 位作者 Shiyuan LIU Jie LI Yu WANG Jicheng HAN Yong GUO 《Agricultural Biotechnology》 CAS 2021年第4期130-133,共4页
In order to evaluate the effects of soil depth on the contents of soil organic nitrogen,organic nitrogen forms in apple-pear orchard soil profile were quantified using the method proposed by Bremner in 1965.The result... In order to evaluate the effects of soil depth on the contents of soil organic nitrogen,organic nitrogen forms in apple-pear orchard soil profile were quantified using the method proposed by Bremner in 1965.The results indicated that in addition to the amino sugar-N,all the soil organic N components within the same soil layer in wasteland were more than those in apple-pear orchard soil;with the layer depth increasing,the contents of different organic nitrogen forms in apple-pear orchard soil and wasteland were decreased;and the proportion of each organic N component within total hydrolysable N was different,and the percentages of ammonia N and amino acid-N components within total hydrolysable N were higher,especially the percentage of ammonia N components within total hydrolysable N was the highest. 展开更多
关键词 Organic nitrogen components PROFILE Apple-pear orchard soil distribution characteristics
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Robust Variance Components Estimation in the PERG Mixed Distributions of Empirical Variances—PEROBVC Method
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作者 Perović Gligorije 《Open Journal of Statistics》 2020年第4期640-650,共11页
A mixed distribution of empirical variances, composed of two distributions the basic and contaminating ones, and referred to as PERG mixed distribution of empirical variances, is considered. In the paper a robust inve... A mixed distribution of empirical variances, composed of two distributions the basic and contaminating ones, and referred to as PERG mixed distribution of empirical variances, is considered. In the paper a robust inverse problem solution is given, namely a (new) robust method for estimation of variances of both distributions—PEROBVC Method, as well as the estimates for the numbers of observations for both distributions and, in this way also the estimate of contamination degree. 展开更多
关键词 Non-Homogeneous Sets of Empirical Variances PERG Mixed distribution of Empirical Variances Robust Variance components Estimation—PEROBVC Method
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Analysis of College Students’ Test Scores Based on Two-Component Mixed Generalized Normal Distribution
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作者 Luliang Wen Haiwu Rong Yanjun Qiu 《Journal of Data Analysis and Information Processing》 2023年第1期69-80,共12页
In order to improve the fitting accuracy of college students’ test scores, this paper proposes two-component mixed generalized normal distribution, uses maximum likelihood estimation method and Expectation Conditiona... In order to improve the fitting accuracy of college students’ test scores, this paper proposes two-component mixed generalized normal distribution, uses maximum likelihood estimation method and Expectation Conditional Maxinnization (ECM) algorithm to estimate parameters and conduct numerical simulation, and performs fitting analysis on the test scores of Linear Algebra and Advanced Mathematics of F University. The empirical results show that the two-component mixed generalized normal distribution is better than the commonly used two-component mixed normal distribution in fitting college students’ test data, and has good application value. 展开更多
关键词 Two-component Mixed Generalized Normal distribution Two-component Mixed Normal distribution ECM Algorithm Test Scores
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Spatial differences in soybean bioactive components across China and their influence by weather factors 被引量:3
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作者 Wenwen Song Ruping Yang +10 位作者 Xiushi Yang Shi Sun Srinivasa Rao Mentreddy Bingjun Jiang Tingting Wu Shiyan Tian Enoch Sapey Cunxiang Wu Wensheng Hou Guixing Ren Tianfu Han 《The Crop Journal》 SCIE CAS CSCD 2018年第6期659-668,共10页
Bioactive components are partially responsible for the nutritional and health benefits of soybeans. Four major bioactive components: isoflavones, oligosaccharides, phospholipids,and saponins, were quantified in 763 so... Bioactive components are partially responsible for the nutritional and health benefits of soybeans. Four major bioactive components: isoflavones, oligosaccharides, phospholipids,and saponins, were quantified in 763 soybean samples collected from widely distributed regions across China from 2010 to 2013. A majority of the tested bioactive components showed generally declining trends from the north(high latitude) to the south(low latitude).A positive relationship between total oligosaccharides(TO) and altitude was observed. Total isoflavones(TI), phospholipids(TP) and TO were negatively correlated with cumulative temperature above or equal to 15 °C(AT15) and mean daily temperature(MDT), but positively correlated with diurnal temperature range(DTR) and hours of sunshine(HS).Total saponins(TS) were negatively correlated with MDT but positively correlated with rainfall(RF), whereas TO were negatively correlated with RF. Path-coefficient analysis showed that, besides genotype differences, temperature and HS during the reproductive period influenced TI and TP contents, while temperature and RF influenced TS and TO. The effects of weather factors on soybean bioactive components in diverse regions of China were characterized. These findings will be helpful in promoting soybean production for functional food purposes. 展开更多
关键词 SOYBEAN GEOGRAPHIC distribution Bioactive componentS WEATHER FACTORS
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Component modification of steel slag in air quenching process to improve grindability 被引量:4
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作者 宗燕兵 苍大强 +2 位作者 甄云璞 李宇 白皓 《中国有色金属学会会刊:英文版》 CSCD 2009年第S3期834-839,共6页
A new solution called component modification in-process was introduced to the difficult grinding of air quenching steel slag by a series of experiments. The results show that the fly ash added into the molten steel sl... A new solution called component modification in-process was introduced to the difficult grinding of air quenching steel slag by a series of experiments. The results show that the fly ash added into the molten steel slag before air quenching can more effectively improve the slag's grindability than milltailings, which is the other modification agent tested under the same conditions. The role of fly ash is strengthened as its proportion increases, although the degree of promotion is gradually reduced. As a result of the reaction between fly ash and steel slag at high temperature, some new mineral phases and vitreous bodies with fine grindability promote the slag grinding easily. This work is helpful to making a comprehensive utilization of steel slag and maximize its economic efficiency in China. 展开更多
关键词 steel SLAG component MODIFICATION in-process AIR QUENCHING GRINDABILITY PARTICLE distribution
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Performance of FCC Catalyst Improved with Vanadium Trapping Components 被引量:6
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作者 Ren Fei Liu Qianqian Zhu Yuxia 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第2期8-11,共4页
The vanadium species were contaminated on FCC catalysts by using the Mitchell method. After the hydrothermal deactivation of the FCC catalysts, the cracking reaction was performed on these catalyst samples. The test r... The vanadium species were contaminated on FCC catalysts by using the Mitchell method. After the hydrothermal deactivation of the FCC catalysts, the cracking reaction was performed on these catalyst samples. The test results revealed that the conversion of feedstock and the gasoline yield obtained over the FCC catalysts with vanadium trapping components were obviously higher than those without addition of vanadium trapping components. The results also showed that the dry gas and coke selectivity on the FCC catalysts containing vanadium trapping components was improved. The X-Ray diffraction results proved that the zeolite crystal structure was well protected by the vanadium trapping components during its hydrothermal deactivation step. The results of SEM-EDX mapping disclosed that the vanadium was enriched on the vanadium trapping components which verified the positive function of vanadium trapping components. 展开更多
关键词 catalytic cracking vanadium trapping components distributION vanadium poisoning
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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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Distributed Technology of E-Business and Its Practice
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作者 LIN Qing-yang, ZHOU Sun, JI Guo-li, ZHANG Xiao-bo, SU Qin (Department of Automation, Xiamen University, Xiamen 361005, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期293-294,共2页
With the evolution of application system, there are t wo different system architectures. One is the traditional application system suc h as MIS and Business Software. Along with its extension, the traditional applic a... With the evolution of application system, there are t wo different system architectures. One is the traditional application system suc h as MIS and Business Software. Along with its extension, the traditional applic ation system transforms from file-based structure to C/S and then CSS model. At the same time, following the prevalence of Internet/Intranet, Web application s ystem based on browser comes into being. In early time, Web application only pro vided functions of looking over or querying static data on browser. But with the development of Internet/Intranet widely, it’s expected that more and more trad itional applications can be performed on browser, or even E-Business trades and other complicated application systems such as MIS, ERP and CRM and so on. In or der to satisfy both traditional application and Web application, reduce the cost of developing system repeatedly, increase the repeated use of application syste m and take advantage of the functions of OOA/OOD sufficiently, a new distributed architecture structure (system solution based on repeated components) comes for th. In this article, this distributed architecture structure will be discuss ed in detail. Firstly, the evolution of traditional application system and Web application sys tem will be talked over, especially the advantages and disadvantages of these tw o architectures. Secondly, the distributed architecture (system solution based o n repeated components) will be described particular. Several prevalent technolog y of component, such as COM+, CORBA and EJB, will also be illustrate d in this part. Thirdly, the practice of the technology of repeated component wi ll be discussed by analysing and designing the management system of Science & Te chnology Articles. Lastly, the latest distributed techonlogy of E-business(Web service based on xml/soap) will be discussed. In the end, Based on summing-up o f the distributed technology of E-Business, the future distributed tenchnology of E-Business will be expected. 展开更多
关键词 system architecture structure distributed techno logy of component science & technology articles management Web service
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A distributed software architecture design framework based on attributed grammar
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作者 贾晓琳 覃征 +1 位作者 何坚 虞凡 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第6期513-518,共6页
Software architectures shift the focus of developers from lines-of-code to coarser-grained architectural elements and their overall interconnection structure. There are, however, many features of the distributed softw... Software architectures shift the focus of developers from lines-of-code to coarser-grained architectural elements and their overall interconnection structure. There are, however, many features of the distributed software that make the developing methods of distributed software quite different from the traditional ways. Furthermore, the traditional centralized ways with fixed interfaces cannot adapt to the flexible requirements of distributed software. In this paper, the attributed grammar (AG) is extended to refine the characters of distributed software, and a distributed software architecture description language (DSADL) based on attributed grammar is introduced, and then a model of integrated environment for software architecture design is proposed. It can be demonstrated by the practice that DSADL can help the programmers to analyze and design distributed software effectively, so the efficiency of the development can be improved greatly. 展开更多
关键词 Software architecture Attributed grammar distributed software component
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Application of the Two Nonzero Component Lemma in Resource Allocation
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作者 Morteza Seddighin 《Journal of Applied Mathematics and Physics》 2014年第7期653-661,共9页
In this paper we will generalize the author's two nonzero component lemma to general self-reducing functions and utilize it to find closed from answers for some resource allocation problems.
关键词 TWO Nonzero component LEMMA Resource ALLOCATION The distribution of the Search EFFORT
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Model-based Predictive Control for Spatially-distributed Systems Using Dimensional Reduction Models 被引量:3
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作者 Meng-Ling Wang Ning Li Shao-Yuan Li 《International Journal of Automation and computing》 EI 2011年第1期1-7,共7页
In this paper, a low-dimensional multiple-input and multiple-output (MIMO) model predictive control (MPC) configuration is presented for partial differential equation (PDE) unknown spatially-distributed systems ... In this paper, a low-dimensional multiple-input and multiple-output (MIMO) model predictive control (MPC) configuration is presented for partial differential equation (PDE) unknown spatially-distributed systems (SDSs). First, the dimension reduction with principal component analysis (PCA) is used to transform the high-dimensional spatio-temporal data into a low-dimensional time domain. The MPC strategy is proposed based on the online correction low-dimensional models, where the state of the system at a previous time is used to correct the output of low-dimensional models. Sufficient conditions for closed-loop stability are presented and proven. Simulations demonstrate the accuracy and efficiency of the proposed methodologies. 展开更多
关键词 Spatially-distributed system principal component analysis (PCA) time/space separation dimension reduction model predictive control (MPC).
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Components Admissible Solution of Algebraic Differential Equations Systems
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作者 LI Guo-wang GAO Ling-yun 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期457-461,共5页
Using the Nevanlinna value distribution theory of meromorphic function,we investigate the existence problem of admissible solutions of higher-order algebraic differential equations systems,and obtain a result concerni... Using the Nevanlinna value distribution theory of meromorphic function,we investigate the existence problem of admissible solutions of higher-order algebraic differential equations systems,and obtain a result concerning admissible components of solution. 展开更多
关键词 value distribution differential equation components admissible solution
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