- Research Progress of Airborne Laser Bathymetry Technology
- Big Data GIS
- Web GIS Component
- An Improved Cellular Automata Model for Simulating Pedestrian Evacuation
- Big Data in Smart City
- Probability Estimation of Future Earthquakes in China Based on Improved PSHA Model
- Experimental Geography Based on Virtual GeographicEnvironments(VGEs)
- Introduction to Urban Computing
- Detecting “Hot Spots” of Facility POIs Based on Kernel Density Estimation and Spatial Autocorrelation Technique
- Integrated Space-Air-Ground Early Detection, Monitoring and Warning System for Potential Catastrophic Geohazards
- The Spatial-Temporal Pattern Analysis of City Development in Countries along the Belt and Road Initiative Based on Nighttime Light Data
- Review of Change Detection Methods for Multi-temporal Remote Sensing Imagery
- On Construction of China’s Space Information Network
- Oblique Image Based Automatic Aerotriangulation and Its Application in 3D City Model Reconstruction
Download CenterMore >
Our journal now offers three free and easy-to-use services designed to alert users as soon as new Web Edition content is published online. All methods ensure that you are alerted when new content that interests you becomes available.
If you have multiple Email addresses, please repeat the subscription.
Basic Directions and Technological Path for Building 3D Realistic Geospatial Scene in China
Digital development has been vigorously promoted in China to drive a comprehensive and in-depth change in production, life and governance through the construction of digital economy, digital society and digital government. It has put forward new and higher requirements for basic surveying and mapping products and services. Recently, the Ministry of Natural Resources of the People's Republic of China issued a notice to promote the construction of 3D realistic geospatial scene of China, aiming to develop new 3D geo-spatial information products which can describe and represent the real 3D spaces of industrial production, living environment and ecological development. The construction of such 3D realistic geospatial scene of China will lead to a 3D digital space which can be well connected with the real geo-spatial space through real-time inter-connection, and will provide a new generation of spatiotemporal information framework for the development of digital China. It is not only a major task for national and local basic surveying and mapping agencies in the next few decades, but also a challenging scientific and technological initiative where several complex factors and technical problems remain to be solved. This paper analyzes the background and problems, discusses the development directions and general technical logic, and conductes the major technological path.
Multi-source Data Ground Object Extraction Based on Knowledge-Aware and Multi-scale Feature Fusion Network
Thoughts on the Future Development of Geographic Information System
Geographic Information System has made great progress in theory and technology in recent 60 years. The application field of GIS has expanded to all aspects of society, and the social influence is increasable growing. The architecture, development mode and service mode of GIS have undergone profound changes. In order to promote the further development of GISystem, this paper focused on the following three issues based on summarizing the three meanings of "S" in "GIS", namely "System" "Science" and "Service", and the fruitful achievements of "GIS" in recent 60 years. The first issue is how to understand GISystem. This issue should be analyzed from two aspects, and one is to discuss the connotation of geographic information system through analyzing the three key words (namely system, information and geographic) of GIS. The other one is to analyze the relationship between GIS and map, computer mapping and map database. This paper holds the idea that GIS originates from and goes beyond map, computer mapping and map database. It should be considered that GIS has the characteristics of equipment. The second issue is how does GIS evolve. This issue focuses on the social demand background, technical background and discipline background of the development and evolution from "Geographic Information System" to "Geographic Information Service". It also focuses on the main manifestations of the development and evolution of GIS from the aspects of application field, expansion of data resources and functions, architecture, development mode and service mode. The third issue is where will the future development of GIS go. We discussed that the limit application domain expansion of GIS and point out that the future development of GIS must face the urgent needs of national economic construction and national defense construction. Based on the analysis and comparison of three existing GISystem service modes, we consider that the "hybrid" technology system of "grid integration" and "elastic cloud" is the best choice for GISystem service mode. Finally, this paper puts forward six key technical problems that must be solved in the implementation of "hybrid" spatiotemporal big data platform technology based on "grid integration" and "elastic cloud"and designs the application mode of "spatiotemporal big data platform".
Concept of Constructing the Underwater PNT Network with the Abilities of Communication, Navigation and Remote Sensing in the Deep Sea
This paper introduces the current situation of constructing the seafloor geodetic network from design, layout, measurement, and data processing. Based on the requirements of national ocean strategy and the development of marine geodetic technology, the problems of the construction of seafloor geodetic networks at the present stage are analyzed. According to the results, it can be concluded the coverage of the current seafloor geodetic network is limited, and the information sharing is insufficient. In addition, the design and layout principles are not combined with the positioning precision of the network, which are mostly qualitative descriptions and lack operability. The accuracy and resolution of the sound velocity field are low and the measurement and data processing are difficult to meet the requirements of large-scale and high-precision underwater PNT (positioning, navigation and timing) network construction. To solve the mentioned problems, the concept of constructing the underwater PNT network with remote communication, information interconnection and telemetry is put forward. Several key technologies, including the design and layout of the underwater PNT network, the construction of the ocean sound velocity field with high precision and high resolution, the measurement strategy, data processing method and the thought of self-calibration and self-maintenance for underwater control points, the function of target and environment telemetry and sensing services, are discussed to provide support for the new generation of high-performance marine geodetic survey and the construction of underwater PNT network. It is believed that the proposed network system will lead to a revolution in underwater PNT construction when problems such as the optimal design of the large-scale network, enhancing positioning service, the accurate timing and time synchronization, remote communication and the extension of the application are broken through.
The Mission of Geo-spatial Information Science in New Infrastructure Era
On September 16th, 2021, general secretary Xi Jinping pointed out in his congratulatory letter to the first international summit on BeiDou scale application: At present, the development of global digitalization is accelerating, and spatiotemporal information, location and navigation services have become an important new infrastructure. With the advent of the new infrastructure era, people engaged in surveying and mapping should think about what the country wants, be anxious about what the country is anxious about, and devote themselves to the wave of "the second 100 years" and "new infrastructure". Firstly, this paper expounds the definition of new infrastructure, and analyzes the difference between new infrastructure and traditional infrastructure. Secondly, it discusses the mission of geo-spatial information science in the three systems of new infrastructure, including information infrastructure, integration infrastructure and innovation infrastructure. The authors believed that we have walked through the so called traditional surveying and mapping which mainly serves topographic maps, and developed into the so called ubiquitous surveying and mapping which mainly focuses in the services of geo-spatial information. At present, we should seize the opportunity and expand the new mission of geo-spatial informatics science in the new infrastructure era, provide spatiotemporal data with good integrity, strong reality and high accuracy for the new infrastructure, and realize digital industrialization, industry digitization and intelligence.
Scientific Concept and Representation Framework of Maps in the ICT Era
Cartography is a subject whose development was partially restricted due to historical conditions. Compared with the traditional map, driven by new technology and new demands, the mapping objects, representation form, perception channel and user role of maps have all undergone significant changes in the information and communication technology (ICT) era. Therefore, the theoretical framework of cartography needs to be further adapted to the ICT era. This paper firstly analyzes the main characteristics of maps in the ICT era, then discusses the concepts and the scope of representation of modern maps in the new era, and finally tries to build the framework of modern maps including the representation object, information abstraction, map representation and map outcomes. This study is expected to clarify the boundary of extended connotation of cartography research and provide corresponding support for the future development of cartography.
Cartography: From Digital to Intelligent
Firstly, this paper discusses the change in the way of thinking and working of the cartographers and cartographic engineering through data, big data and space-time big data, which promotes cartography to enter a new era of the "fourth scientific paradigm" characterized by "data-intensive computing". Secondly, this paper analyzes the functions and features of the digital transformation results of 4D products, and the progress in diversification and individuation of the map products, and the "design - compilation-publication" integrated digital transformation of mapping, and the feature of the representative atlases published in 2021. Finally, by giving two specific examples, i.e., the intellectualization of map generalization and digital mapping, this paper reviews four evolutionary stages of map generalization in the era of artificial intelligence and summarizes the difficulties and breakthroughs in key technologies, and provides a profound conclusion of the research status and the issues to be further explored in the domain.
Generalized Surveying Data Processing: From Geometric Parameters Calculation to Feature Information Extraction
With the rapid development of technologies in sensor, computer and robotics, the trends of multi-sensor integration and intelligent applications are shown in surveying field. Engineering surveying has developed in the direction of automation, dynamism and intelligence, and is widely used for high-precision measurement of large bridges, water conservancy hubs, high-speed rail subways, highways and other projects, as well as precision industrial measurement in aerospace, aviation, intelligent manufacturing and other fields. The expansion of application fields also puts forward new requirements for surveying tasks.The surveying data processing is no longer limited to the traditional pure geometric parameter estimation, but gradually expands to the generalized measurement data processing with both geometric parameters and feature information. We review the development process from classical measurement data processing to generalized measurement data processing, summarize the processing and analysis logic of multiple types of measurement data, and present the challenges of measurement data processing in the era of big data. The basic ideas and strategies of generalized measurement data processing are elaborated and illustrated with several typical cases.
Coseismic Deformation and Slip Distribution of the 2022 Luding Mw 6.6 Earthquake Revealed by InSAR Observations
Objectives: The 5 September 2022 Mw 6.6 Luding earthquake is the largest earthquake occurring on the Xianshuihe fault, Eastern Tibet in the past 40 years, and is of great significance for investigating the tectonic activity and assessing future seismic hazards in the region. Methods: In this study, we used Sentinel-1 and ALOS-2 synthetic aperture radar (SAR) images to retrieve coseismic surface displacements and then to determine the fault geometry parameters and slip distribution with a dislocation model in an elastic half-space. Results: Our results show that the earthquake is a left-lateral sliding event with a maximum LOS surface displacement of ~15 cm and ~21 cm for the Sentinel-1 and ALOS-2 radar images, respectively. Conclusions: The fault ruptured along an NNW-SSE strike, and westward at a dip of 72°. The slip was concentrated at depths of 0-10 km with a maximum fault slip of 2.23 m occurring at a depth of ~5.8 km. By analyzing the distribution of the coseismic landslides interpreted by optical images, it is found that the coseismic landslides were mainly located on the west side of the fault, which is consistent with the aftershock distribution and can be considered due to hanging wall effects.
Emergency Analysis of the Impact of the Luding Ms 6.8 Earthquake on Hailuogou Glacier
Objectives: An earthquake with the magnitude of Ms 6.8 struck Luding County,Ganzi Prefecture,Sichuan Province on September 5,2022,with the epicenter about 10 km away from Hailuogou Glacier.How Hailuogou Glacier was affected by the earthquake has been widely concerned by the society. Methods: Firstly,the glacier area is monitored based on normalized difference snow index using multi temporal Landsat 8 and Sentinel-2 optical satellite images.Secondly,Sentinel-1 synthetic aperture radar satellite image is used to monitor the displacement before and during the Luding earthquake based on pixel offsettracking technology. Results: The results indicate that the area of Hailuogou Glacier shows a shaking trend from 2016 to 2022,which have a negative correlation with the daily average maximum temperature.While the velocity has a positively correlation with the slope gradient and the daily average maximum temperature.The Luding earthquake did not cause a significant increase in the velocity of Hailuogou Glaciers in a large range,but it significantly disturbed the front area of the ice waterfall. Conclusions: The possibility of direct disaster caused by ice avalanches after the earthquake was low,but which increased the risk of disaster caused by debris flow.
- All visit:
- Today's visit: