Getting insight into the spatiotemporal distribution patterns of knowledge innovation is receiving increasing attention from policymakers and economic research organizations.Many studies use bibliometric data to analy...Getting insight into the spatiotemporal distribution patterns of knowledge innovation is receiving increasing attention from policymakers and economic research organizations.Many studies use bibliometric data to analyze the popularity of certain research topics,well-adopted methodologies,influential authors,and the interrelationships among research disciplines.However,the visual exploration of the patterns of research topics with an emphasis on their spatial and temporal distribution remains challenging.This study combined a Space-Time Cube(STC)and a 3D glyph to represent the complex multivariate bibliographic data.We further implemented a visual design by developing an interactive interface.The effectiveness,understandability,and engagement of ST-Map are evaluated by seven experts in geovisualization.The results suggest that it is promising to use three-dimensional visualization to show the overview and on-demand details on a single screen.展开更多
Reliable and up-to-date geospatial data plays a fundamental role in Sustainable Development Goals(SDGs)monitoring.Aiming to providing such geospa-tial data,numerous algorithms,solutions and frame-works have been devel...Reliable and up-to-date geospatial data plays a fundamental role in Sustainable Development Goals(SDGs)monitoring.Aiming to providing such geospa-tial data,numerous algorithms,solutions and frame-works have been developed in recent years.A mong oth-ers,A rtificial Intelligence(AI)based techniques have been widely used for the tasks of processing geospatial data.Nowadays,this topic is blooming so fast and to a vast extent in the field of Geomatics that a new subdo-main seems to arise,namely GeoAI[1-2].Even for a very quick and brief glance inthe Internet,people can find a lot of applications,projects,blogs and research articles about GeoAI,w hereas new approaches to GeoAI have been proposed and tested.展开更多
The OGC standard for 3D city modeling is widely used in an increasing number of applications. It defines five consecutive Levels of Detail （LoD0 to LoD4 with increasing accuracy and structural complexity）, in which ...The OGC standard for 3D city modeling is widely used in an increasing number of applications. It defines five consecutive Levels of Detail （LoD0 to LoD4 with increasing accuracy and structural complexity）, in which LoD3 includes all exterior appearances and geometrical details and subsequently requires much storage space. A new LoD is introduced as shell model with the exterior shell of the LoD3 model and the opening objects like windows, doors as well as smaller facade objects are projected onto walls. In this paper, a user survey is presented. The results of this survey show that the shell model can give users almost the same visual impression as the LoD3 model. Furthermroe, algorithms are developed to extract the shell model from LoD3 model. Experiments show that this shell model can reduce up to 90% storage of the original LoD3 model. Therefore, on one hand it can be used as a substitute for a LoD3 model for the visualization on small displays. On the other hand, it can be treated as a sub-level of detail （SLoD3） in CityGML, since it retains almost the same amount of information but requires much less storage space.展开更多
文摘Getting insight into the spatiotemporal distribution patterns of knowledge innovation is receiving increasing attention from policymakers and economic research organizations.Many studies use bibliometric data to analyze the popularity of certain research topics,well-adopted methodologies,influential authors,and the interrelationships among research disciplines.However,the visual exploration of the patterns of research topics with an emphasis on their spatial and temporal distribution remains challenging.This study combined a Space-Time Cube(STC)and a 3D glyph to represent the complex multivariate bibliographic data.We further implemented a visual design by developing an interactive interface.The effectiveness,understandability,and engagement of ST-Map are evaluated by seven experts in geovisualization.The results suggest that it is promising to use three-dimensional visualization to show the overview and on-demand details on a single screen.
文摘Reliable and up-to-date geospatial data plays a fundamental role in Sustainable Development Goals(SDGs)monitoring.Aiming to providing such geospa-tial data,numerous algorithms,solutions and frame-works have been developed in recent years.A mong oth-ers,A rtificial Intelligence(AI)based techniques have been widely used for the tasks of processing geospatial data.Nowadays,this topic is blooming so fast and to a vast extent in the field of Geomatics that a new subdo-main seems to arise,namely GeoAI[1-2].Even for a very quick and brief glance inthe Internet,people can find a lot of applications,projects,blogs and research articles about GeoAI,w hereas new approaches to GeoAI have been proposed and tested.
基金the National Natural Science Foundation of China(No. 41071288)
文摘The OGC standard for 3D city modeling is widely used in an increasing number of applications. It defines five consecutive Levels of Detail （LoD0 to LoD4 with increasing accuracy and structural complexity）, in which LoD3 includes all exterior appearances and geometrical details and subsequently requires much storage space. A new LoD is introduced as shell model with the exterior shell of the LoD3 model and the opening objects like windows, doors as well as smaller facade objects are projected onto walls. In this paper, a user survey is presented. The results of this survey show that the shell model can give users almost the same visual impression as the LoD3 model. Furthermroe, algorithms are developed to extract the shell model from LoD3 model. Experiments show that this shell model can reduce up to 90% storage of the original LoD3 model. Therefore, on one hand it can be used as a substitute for a LoD3 model for the visualization on small displays. On the other hand, it can be treated as a sub-level of detail （SLoD3） in CityGML, since it retains almost the same amount of information but requires much less storage space.
