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
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
Aiming at the problem that the distance between the main roadway and the working face in Hudi Coal Industry Panel was more than 100 m,which was still affected by mining,high stress concentration of the roadway,and dif...Aiming at the problem that the distance between the main roadway and the working face in Hudi Coal Industry Panel was more than 100 m,which was still affected by mining,high stress concentration of the roadway,and difficulty of supporting overall convergence of the section,the mechanical characteristics of the core bearing strata of the overlying rock caving in the working face were studied.The correlation mechanism between the overlying rock caving and the deformation and failure of the roadway was analyzed,and the quantitative evaluation index was established to comprehensively analyze different influencing factors.Based on the key strata theory,the mechanical difference transfer model of working face mining and panel roadway deformation and failure was established.It was considered that the difference in fracture morphology was the key to the far-field stress disturbance.The regional stress control technology was proposed to block or reduce the stress transfer,so that the peak stress of the panel main roadway was reduced,and the deformation of the surrounding rock was significantly reduced,which provides a reference value for the roadway support with serious influence of mining roadway.展开更多
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(2024B03017)supported by the Key Research and Development Program Projects of Xinjiang Uygur Autonomous Region,ChinaProjects(52225404,52394192)supported by the National Natural Science Foundation of China。
文摘Aiming at the problem that the distance between the main roadway and the working face in Hudi Coal Industry Panel was more than 100 m,which was still affected by mining,high stress concentration of the roadway,and difficulty of supporting overall convergence of the section,the mechanical characteristics of the core bearing strata of the overlying rock caving in the working face were studied.The correlation mechanism between the overlying rock caving and the deformation and failure of the roadway was analyzed,and the quantitative evaluation index was established to comprehensively analyze different influencing factors.Based on the key strata theory,the mechanical difference transfer model of working face mining and panel roadway deformation and failure was established.It was considered that the difference in fracture morphology was the key to the far-field stress disturbance.The regional stress control technology was proposed to block or reduce the stress transfer,so that the peak stress of the panel main roadway was reduced,and the deformation of the surrounding rock was significantly reduced,which provides a reference value for the roadway support with serious influence of mining roadway.
