In order to establish the baseline finite element model for structural health monitoring,a new method of model updating was proposed after analyzing the uncertainties of measured data and the error of finite element m...In order to establish the baseline finite element model for structural health monitoring,a new method of model updating was proposed after analyzing the uncertainties of measured data and the error of finite element model.In the new method,the finite element model was replaced by the multi-output support vector regression machine(MSVR).The interval variables of the measured frequency were sampled by Latin hypercube sampling method.The samples of frequency were regarded as the inputs of the trained MSVR.The outputs of MSVR were the target values of design parameters.The steel structure of National Aquatic Center for Beijing Olympic Games was introduced as a case for finite element model updating.The results show that the proposed method can avoid solving the problem of complicated calculation.Both the estimated values and associated uncertainties of the structure parameters can be obtained by the method.The static and dynamic characteristics of the updated finite element model are in good agreement with the measured data.展开更多
Based on the statistical characteristics of remote sensing data, the spatial geometric structure characteristics of spectral data and distribution of background, interference and alteration information in characterist...Based on the statistical characteristics of remote sensing data, the spatial geometric structure characteristics of spectral data and distribution of background, interference and alteration information in characteristic space were researched through the analysis of two-dimensional and three-dimensional scatter diagrams. The results indicate that the hyper-space of remote sensing multi-data aggregation belongs to low-dimensional geometric structure, i.e. hyperplane form, and anomalous point groups including alteration information usually dissociate out of hyperplane. Scatter diagrams of remote sensing data band are mainly presented as two distribution forms of single-ellipse and dual-ellipse. Clarifying the relations of three objects of background, disturbance and alteration information in remote sensing images provides an important technical thought and guidance for accurately detecting and extracting remote sensing alteration information.展开更多
In recent years,regional integration of Chinese cities has gradually developed.Meanwhile,metropolitan areas and urban agglomerations have taken shape.On the one hand,the development of the metropolitan area has brough...In recent years,regional integration of Chinese cities has gradually developed.Meanwhile,metropolitan areas and urban agglomerations have taken shape.On the one hand,the development of the metropolitan area has brought about urban spatial expansion,as well as population and economic growth.On the other hand,it has led to problems such as the urban sprawl and suburbanization,increasing pressure on environmental resources,and the decline of urban central areas.Under this background,the Guangdong-Hong Kong-Macao Greater Bay Area Development Plan Outline proposes to accelerate the integration of Guangzhou-Foshan(Guang Fo)Metropolitan Coordinating Region(MCR),and to construct a networked space pattern driven by urban poles and shafts.Based on the academic research of Metropolitan Coordinating Region(MCR),as well as the theory of urban spatial structure and morphology,this study focus on urban spatial patterns and elements in different scales,from two individual cites(Guangzhou and Foshan),Guang Fo MCR,to Guangdong-Hong Kong-Macao(GHM)Greater Bay Area.With GIS and the mapping method,the spatial elements such as green space,water system,built-up area,road network,rail transit network and main pivot points of the Guang Fo MCR are classified,laid out individually and again overlaid in order to figure out the relationship of these elements.At the same time,through the comparative case study of the Randstad MCR in the Netherlands,the enlightenment of solving the development problem of MCR is hopefully to be obtained.As delta cities,the Guang Fo MCR is cut by the multi-channel water network,while the urban built-up area is concentrated in the middle of the MCR and spread out along the traffic corridor to the suburban district.The traffic structure of the Guang Fo MCR is characterized by the outward radiation of the central area of Guangzhou and Foshan.Simultaneously,the traffic connection between Guangzhou and Foshan is relatively weak.Compared with the polycentric spatial structure,which is called Decentralized Compact pattern of Randstad MCR,the Guang Fo MCR presents a city form with little hierarchy but homogeneity,and its urban space is disorderly spread.The bluegreen system of water and vegetation is fragmented because of the urban invasion in Guang Fo MCR,while the green heart in central Randstad is well preserved.As a result,it is well advised to explore a more resilient and ecological urban development in Guang Fo MCR.展开更多
As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decompos...As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decomposition of the input space by DiPLS,there are false alarms in the actual industrial process during fault detection.To address the above problems,a dynamic modeling method based on autoregressive-dynamic inner total PLS(AR-DiTPLS)is proposed.The method first uses the regression relation matrix to decompose the input space orthogonally,which reduces useless information for the predic-tion output in the quality-related dynamic subspace.Then,a vector autoregressive model(VAR)is constructed for the predic-tion score to separate dynamic information and static informa-tion.Based on the VAR model,appropriate statistical indicators are further constructed for online monitoring,which reduces the occurrence of false alarms.The effectiveness of the method is verified by a Tennessee-Eastman industrial simulation process and a three-phase flow system.展开更多
基金Project(50678052) supported by the National Natural Science Foundation of China
文摘In order to establish the baseline finite element model for structural health monitoring,a new method of model updating was proposed after analyzing the uncertainties of measured data and the error of finite element model.In the new method,the finite element model was replaced by the multi-output support vector regression machine(MSVR).The interval variables of the measured frequency were sampled by Latin hypercube sampling method.The samples of frequency were regarded as the inputs of the trained MSVR.The outputs of MSVR were the target values of design parameters.The steel structure of National Aquatic Center for Beijing Olympic Games was introduced as a case for finite element model updating.The results show that the proposed method can avoid solving the problem of complicated calculation.Both the estimated values and associated uncertainties of the structure parameters can be obtained by the method.The static and dynamic characteristics of the updated finite element model are in good agreement with the measured data.
基金Project(2006BAB01A06) supported by the National Science and Technology Pillar Program Project during the 11th Five-Year Plan PeriodProject(1212010761503) supported by Land and Resources Investigation Project
文摘Based on the statistical characteristics of remote sensing data, the spatial geometric structure characteristics of spectral data and distribution of background, interference and alteration information in characteristic space were researched through the analysis of two-dimensional and three-dimensional scatter diagrams. The results indicate that the hyper-space of remote sensing multi-data aggregation belongs to low-dimensional geometric structure, i.e. hyperplane form, and anomalous point groups including alteration information usually dissociate out of hyperplane. Scatter diagrams of remote sensing data band are mainly presented as two distribution forms of single-ellipse and dual-ellipse. Clarifying the relations of three objects of background, disturbance and alteration information in remote sensing images provides an important technical thought and guidance for accurately detecting and extracting remote sensing alteration information.
基金the financial support given by National Natural Science Foundation Projects of International Cooperation and Exchange of China(No.51761135025)National Natural Science Foundation General Program of China(No.51778233)Science and Technology Program of Guangzhou,China(No.201707020041)
文摘In recent years,regional integration of Chinese cities has gradually developed.Meanwhile,metropolitan areas and urban agglomerations have taken shape.On the one hand,the development of the metropolitan area has brought about urban spatial expansion,as well as population and economic growth.On the other hand,it has led to problems such as the urban sprawl and suburbanization,increasing pressure on environmental resources,and the decline of urban central areas.Under this background,the Guangdong-Hong Kong-Macao Greater Bay Area Development Plan Outline proposes to accelerate the integration of Guangzhou-Foshan(Guang Fo)Metropolitan Coordinating Region(MCR),and to construct a networked space pattern driven by urban poles and shafts.Based on the academic research of Metropolitan Coordinating Region(MCR),as well as the theory of urban spatial structure and morphology,this study focus on urban spatial patterns and elements in different scales,from two individual cites(Guangzhou and Foshan),Guang Fo MCR,to Guangdong-Hong Kong-Macao(GHM)Greater Bay Area.With GIS and the mapping method,the spatial elements such as green space,water system,built-up area,road network,rail transit network and main pivot points of the Guang Fo MCR are classified,laid out individually and again overlaid in order to figure out the relationship of these elements.At the same time,through the comparative case study of the Randstad MCR in the Netherlands,the enlightenment of solving the development problem of MCR is hopefully to be obtained.As delta cities,the Guang Fo MCR is cut by the multi-channel water network,while the urban built-up area is concentrated in the middle of the MCR and spread out along the traffic corridor to the suburban district.The traffic structure of the Guang Fo MCR is characterized by the outward radiation of the central area of Guangzhou and Foshan.Simultaneously,the traffic connection between Guangzhou and Foshan is relatively weak.Compared with the polycentric spatial structure,which is called Decentralized Compact pattern of Randstad MCR,the Guang Fo MCR presents a city form with little hierarchy but homogeneity,and its urban space is disorderly spread.The bluegreen system of water and vegetation is fragmented because of the urban invasion in Guang Fo MCR,while the green heart in central Randstad is well preserved.As a result,it is well advised to explore a more resilient and ecological urban development in Guang Fo MCR.
基金supported by the National Natural Science Foundation of China(62273354,61673387,61833016).
文摘As a dynamic projection to latent structures(PLS)method with a good output prediction ability,dynamic inner PLS(DiPLS)is widely used in the prediction of key performance indi-cators.However,due to the oblique decomposition of the input space by DiPLS,there are false alarms in the actual industrial process during fault detection.To address the above problems,a dynamic modeling method based on autoregressive-dynamic inner total PLS(AR-DiTPLS)is proposed.The method first uses the regression relation matrix to decompose the input space orthogonally,which reduces useless information for the predic-tion output in the quality-related dynamic subspace.Then,a vector autoregressive model(VAR)is constructed for the predic-tion score to separate dynamic information and static informa-tion.Based on the VAR model,appropriate statistical indicators are further constructed for online monitoring,which reduces the occurrence of false alarms.The effectiveness of the method is verified by a Tennessee-Eastman industrial simulation process and a three-phase flow system.
