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    20 October 2017, Volume 46 Issue 10
    From Geomatics to Geospatial Intelligent Service Science
    LI Deren
    2017, 46(10):  1207-1212.  doi:10.11947/j.AGCS.2017.20170263
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    The paper reviews the 60 years of development from traditional surveying and mapping to today's geospatial intelligent service science.The three important stages of surveying and mapping, namely analogue,analytical and digital stage are summarized.The author introduces the integration of GNSS,RS and GIS(3S),which forms the rise of geospatial informatics(Geomatics).The development of geo-spatial information science in digital earth era is analyzed,and the latest progress of geo-spatial information science towards real-time intelligent service in smart earth era is discussed.This paper focuses on the three development levels of "Internet plus" spatial information intelligent service.In the era of big data,the traditional geomatics will surely take advantage of the integration of communication,navigation,remote sensing,artificial intelligence,virtual reality and brain cognition science,and become geospatial intelligent service science,thereby making contributions to national economy,defense and people's livelihood.
    Progresses from Surveying and Mapping to Geomatics
    NING Jinsheng, WANG Zhengtao
    2017, 46(10):  1213-1218.  doi:10.11947/j.AGCS.2017.20170375
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    This paper aims to look back the three-step progresses of the Surveying and Mapping science and technology from traditional surveying and mapping to digital surveying and mapping, and then to informatization surveying and mapping which is also called Geomatics. It mainly discusses the changes and developments of the surveying and mapping science and technology in terms of the concept, theory, technology, method, application service and so on, with the evolution of the national needs and world science and technology developments. Besides, the way from Surveying and Mapping to Geomatics is also presented in detail, together with the changes of the concepts, disciplines and connotations in the Surveying and Mapping. Finally, the basic conceptions and definitions of digital surveying and mapping and Geomatics are given.
    The 60 Anniversary and Prospect of Acta Geodaetica et Cartographica Sinica
    GAO Jun
    2017, 46(10):  1219-1225.  doi:10.11947/j.AGCS.2017.20170503
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    Four areas that should be paid special attention are put forward. Firstly, the field of surveying and mapping services has extended from the surface of the earth to the virtual multi-dimensional space (cyberspace). Secondly, the service direction of surveying and mapping products should be expanded from human to intelligent robot. Thirdly, in order to improve the cultural connotation of the map, it should be initiative to move closer to several aspects of the cultural and social sciences. Fourthly, the supply-side structural reform of surveying and mapping technology and industry has been put on the agenda, breakthrough changes should be taken place in all aspects.
    Cartography in the Age of Spatio-temporal Big Data
    WANG Jiayao
    2017, 46(10):  1226-1237.  doi:10.11947/j.AGCS.2017.20170308
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    Cartography is an ancient science with almost the same long history as the world's oldest culture.Since ancient times,the movement and change of anything and any phenomena,including human activities,have been carried out in a certain time and space.The development of science and technology and the progress of social civilization have made social management and governance more and more dependent on time and space.The information source,theme,content,carrier,form,production methods and application methods of map are different in different historical periods,so that its all-round value is different. With the arrival of the big data age,the scientific paradigm has now entered the era of "data-intensive" paradigm,so is the cartography,with obvious characteristics of big data science.All big data are caused by movement and change of all things and phenomena in the geographic world,so they have space and time characteristics and thus cannot be separated from the spatial reference and time reference.Therefore,big data is big spatio-temporal data essentially.Since the late 1950s and early 1960s,modern cartography,that is,the cartography in the information age,takes spatio-temporal data as the object,and focuses on the processing and expression of spatio-temporal data,but not in the face of the large scale multi-source heterogeneous and multi-dimensional dynamic data flow(or flow data)from sky to the sea.The real-time dynamic nature,the theme pertinence,the content complexity,the carrier diversification,the expression form personalization,the production method modernization,the application ubiquity of the map,is incomparable in the past period,which leads to the great changes of the theory,technology and application system of cartography.And all these changes happen to occur in the 60 years since the late 1950s and early 1960s,so this article was written to commemorate the 60th anniversary of the "Acta Geodaetica et Cartographica Sinica".
    An Overview on “Cloud Control” Photogrammetry in Big Data Era
    ZHANG Zuxun, TAO Pengjie
    2017, 46(10):  1238-1248.  doi:10.11947/j.AGCS.2017.20170337
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    In the present era of big data, photogrammetric image collection modes are characterized with the progressive course of diversity, efficiency and facilitation, which are producing large sets of photogrammetric image data. They further bring the request for advanced processing with higher level of efficiency, automation and intelligence. However, the efficiency of fundamental photogrammetric processing, known as geometric positioning, is still majorly restricted to control points acquired through complex and inefficient field works. In view of this problem, we promote the concept of "cloud control" photogrammetry, which regards geo-encoded data as geometric control instead of field control points, and is achieved via control information extraction with extensive and intensive automatic matching (or registration) technology. Three control modes will be introduced, considered as image-based-control, vector-map-based-control and LiDAR-point-based-control respectively. By the end of the paper, we provide the discussion on the application prospects and foreseeable problems of "cloud control" photogrammetry.
    Micro-PNT and Comprehensive PNT
    YANG Yuanxi, LI Xiaoyan
    2017, 46(10):  1249-1254.  doi:10.11947/j.AGCS.2017.20170249
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    Comprehensive or integrated positioning, navigation and timing is an obvious developing trend following the global navigation satellite system.This paper summarizes the current status of micro-PNT and its developing requirements. The related key technologies are described and the relationship between comprehensive PNT and micro-PNT is analyzed. It is stressed that the comprehensive PNT needs massive infrastructure construction and investment, however, the micro-PNT aims at the integrated applications of high-tech micro sensors. It is different from the current opinions appeared in the literatures, micro-PNT should include multi GNSS integration and micro components of navigation and timing in order to make the PNT outputs refer to a unified coordinate datum and time scale. Micro-PNT focuses on the personalized micro terminal applications. Except for the miniaturization of each PNT component, micro-PNT aims at the deep integration of the micro sensors, adaptive data fusion and self calibration of each component.
    High-precision Geometric Processing Theory and Method of High-resolution Optical Remote Sensing Satellite Imagery without GCP
    GONG Jianya, WANG Mi, YANG Bo
    2017, 46(10):  1255-1261.  doi:10.11947/j.AGCS.2017.20170307
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    Global high-precision geolocation of satellite imagery without GCP is the main goal of satellite photogrammetry,and the fundamental supporting technology of mapping in abroad area.For the developing technology of domestic remote sensing satellite,this paper presents the high-precision geometric processing theory and method of high-resolution optical remote sensing satellite imagery without GCP.Based on rigorous analysis of satellite observation error model,on-orbit geometric calibration method,virtual re-imaging processing method and large-scale block adjustment method are proposed.Experiments were conducted by using ZY-3 imagery.The result fulfills the demand of 1:50 000 mapping,and proves the correctness of proposed theory and method.
    Determination of Vertical Datum Offset between the Regional and the Global Height Datum
    LI Jiancheng, CHU Yonghai, XU Xinyu
    2017, 46(10):  1262-1273.  doi:10.11947/j.AGCS.2017.20170538
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    The unification of the global height datum is a key problem to be solved for geodesy after the unification of global geodetic coordination system and three-dimension spatial datum, and the basis of global spatial information sharing and exchange. In this paper, the theoretical and practical problems of vertical datum offset between the regional height datum and the global height datum are studied. Based on the classical theory of the height system in physical geodesy, the definition of the height datum vertical offset is given, and the rigorous formulas for calculating the vertical offset are derived. The formulas can be used to deduce the three methods of the height datum vertical offset determination. On that basis, the influences of different reference system and reference ellipsoid parameters on the calculation of the vertical offset are analyzed. The results show that the reference system and the ellipsoid parameter conversion are very necessary. At the same time, the height anomaly differences method needs to consider the degree zero correction caused by the inconsistency between gravity potential of the global height datum and the one computed by the model. Based on potential difference approach and the height anomaly difference method, the vertical offset between the China 1985 national height datum and the global height datum corresponding to the normal gravity potential U0 of GRS80, WGS-84 and CGCS2000 reference ellipsoidal from the 152 GPS/leveling points near the origin of Qingdao height origin and the EGM2008, EIGEN-6C4 and SGG-UGM-1 model. The regional datum is 23.1 cm lower than the global datum based on EIGEN-6C4 and WGS-84. When the Gauss-Listing geoid (mean sea surface) is selected as the global height datum, the China 1985 national height datum is 21.0 cm higher than the global height datum. The results also show that there are still large differences among the accuracies of the current gravity field models on these GPS/Levelling points around Qingdao, which will lead to big differences in estimating the vertical datum offset between the China 1985 national height datum and the global height datum with respect to different selected data sets. Therefore, the accuracy and reliability of the current global gravity field models needs to be further improved if they were used for the height datum vertical offset determination. The theoretical and practical results of this paper could be used for the realization of the unification of the regional height datum and the global height datum.
    The Rejuvenation of Cartography in ICT Era
    GUO Renzhong, YING Shen
    2017, 46(10):  1274-1283.  doi:10.11947/j.AGCS.2017.20170335
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    With the impetus of ICT, cartography faces the unprecedented challenges. The paper discusses the problems and changes of cartography facing the digital technology, analyzes the constraints of traditional cartography that are mainly delimited by 2D physical paper map. Diverseness of modern cartography shows various map products, and the paper illustrates the digital freedom in information space of modern cartography from eight aspects, including physical reality VS virtual reality, paper map VS digital map, superficial visualization VS inner visualization and so on. Modern cartography encounters the new development opportunities and fresh demands in digital era, and it's necessary to extend the framework of cartography and to assimilate newly sprouted things to promote the rejuvenation of cartography.
    Innovative Development and Forecast of BeiDou System
    TAN Shusen
    2017, 46(10):  1284-1289.  doi:10.11947/j.AGCS.2017.20170329
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    Due to the strong demand for satellite applications and rapid development of new space technology,the cross-integration of space-based radio systems has become a trend.BeiDou system started from two satellites to build China's first generation satellite navigation and positioning system with the features of fast location reporting(RDSS)and short message communication(MSS)service.Then BeiDou technology frame combined with RNSS continuous navigation and RDSS location report,was constructed in eight years,and the coverage in Asia-Pacific was completed.Through effective satellite radio frequency compatible design and international coordination,BeiDou system is the first radio satellite system which includes RNSS,RDSS,MSS three major services,approved by International Telecommunication Union(ITU)in the world.This paper expounds the development process,technical frame,main features and prospect of BeiDou system with three major services and four key functions,in the concept of innovation and transcendence.
    Research Progress of the Gravity Field Application in Earth's Geodynamics and Interior Structure
    SUN Heping, XU Jianqiao, CUI Xiaoming
    2017, 46(10):  1290-1299.  doi:10.11947/j.AGCS.2017.20170298
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    The exploration of deep internal structure and internal dynamics of the earth has always been a hot topic in the field of basic geoscience research.Traditional approach relies mainly on seismic technology. However, in recent decades, the innovation of modern gravity observation technology (especially the successful application of high-precision superconducting gravity technology) makes it possible to detect the earth's internal dynamics and physical information. In this paper, we summarize the research progress of Chinese group in detecting the earth's free oscillation, free core nutation, inner core translational oscillation, tidal model and polar tide and the internal structure by using modern high-precision gravity technology in recent years.
    Precision Space Observation Technique for Geological Hazard Monitoring and Early Warning
    ZHANG Qin, HUANG Guanwen, YANG Chengsheng
    2017, 46(10):  1300-1307.  doi:10.11947/j.AGCS.2017.20170453
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    Since the 21st century, with the deterioration of the world environment and the intense human activities, geological disasters have been occurred more frequently. Precision space observation technology is an important means for geological disasters monitoring and early warning. In this paper, the characteristics and monitoring methods of common geological disasters are introduced. The technical characteristics and application of InSAR, LiDAR, high resolution remote sensing and GNSS are discussed. The integration of high precision spatial monitoring technology are reviewed and prospected. Finally, the future trends of the geological disaster monitoring and early warning technology are summarized.
    Algorithm Characteristics of Dynamic Approach-based Satellite Gravimetry and Its Improvement Proposals
    SHEN Yunzhong
    2017, 46(10):  1308-1315.  doi:10.11947/j.AGCS.2017.20170380
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    By using the integration equation for computing satellite orbit, this paper derives the observational equation for computing gravity field model linearized with respect to the reference orbit, provides the integration equation of calculating the design matrices of the observational equation, and clarifies that the dynamic approach is in principle the perturbation method relative to the reference orbit, therefore the initial partial derivatives with respect to the force model parameters must be zero. Based on the derived formulae this paper analyzes the main characteristics of dynamic approach-based observational equation, i.e. the linearization error will rapidly increase and the property of observational equation becomes worse as the integration arc extends longer, and the numerical integration error will be the bottle-neck problem for the data processing of next generation of satellite gravity exploration. Then this paper proposes the methods for improving the accuracy of gravity recovery, which can be summarized as that refining the linearization method relative kinematic orbit to reduce the linearization error, modifying parameterization method to improve the property of observational equation, and combined using analytic formula and numerical integration formula to increase the accuracy of orbit computation.
    Indoor Positioning with Smartphones:The State-of-the-art and the Challenges
    CHEN Ruizhi, CHEN Liang
    2017, 46(10):  1316-1326.  doi:10.11947/j.AGCS.2017.20170383
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    Indoor positioning is one of the core technologies of artificial intelligence (AI) in the future and will play a pivotal role in the upcoming era of AI. Currently, indoor positioning is one of the hot research topics in academic and industrial society. Google, as one of the leading information technology (IT) companies, has listed visual positioning service (VPS) as one of the core technologies. Apple has endeavored to prompt iBeacon, the low energy Bluetooth technology for indoor positioning. In cooperation with a Finnish company, IndoorAltas, Baidu launched an indoor positioning program with a magnetic matching approach. All these initiatives and new technologies have shown the significance and necessaries of indoor positioning. However, affected by the complexity of the indoor spaces, it is still challenging to achieve accurate, effective, full coverage and real-time positioning solution indoors. With the popularity of smart phones and the rapid development of MEMS sensors in recent years, many methods have been proposed to use the smartphone built-in sensors and RF radios for indoor positioning. In this paper, we focus on indoor positioning technologies for smartphones and classify the different technologies into two categories, namely the radio frequency (RF) technologies and the sensors technologies. The state-of-the-art of the technologies has been reviewed. The pros and cons of the technologies have been commented in the context of different application scenarios. Moreover, the challenges of indoor positioning have also been pointed out and the directions of the future development of this area have been discussed.
    The Current Status and Tendency of China Millimeter Coordinate Frame Implementation and Maintenance
    CHENG Pengfei, CHENG Yingyan
    2017, 46(10):  1327-1335.  doi:10.11947/j.AGCS.2017.20170336
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    The paper discusses differences between China Geodetic Coordinate System 2000 (CGCS2000) and later updated ITRF versions, such as ITRF2014, in terms of technical implementation and maintenance. With progress of space geodetic technology, also the development of the BeiDou navigation satellite system, especially third generation of BDS with signal global coverage in the future, it is possible for us to establish a global millimeter-level reference frame based on space geodetic technology including BDS. The millimeter reference frame implementation concerns two factors:① The variation of geocenter motion estimation; ② the site nonlinear motion modeling. In this paper, the geocentric inversion methods are discussed and compared among results derived from various technical methods. Our nonlinear site movement modeling focuses on singular spectrum analysis method, which is of apparent advantages over earth physical effect modeling. All presented in the paper expected to provide reference to our future CGCS2000 maintenance.
    Geodetic Method and Application for Monitoring the Stability of Regional Geological Environment
    DANG Yamin, YANG Qiang, WANG Wei
    2017, 46(10):  1336-1345.  doi:10.11947/j.AGCS.2017.20170324
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    Global geodetic observing system (GGOS) has been widely applied to monitoring the global change. This paper systematically introduces the method for monitoring and evaluating the regional geological environment stability by comprehensively utilizing multi-source geodetic observations, geological and seismic data. Circum-Bohai-Sea area and Sichuan-Yunnan area as two typical cases are studied to introduce the latest progresses and applications in monitoring and evaluating the regional geological environment stability, where the geological environment of the former is characterized by the subsidence while that of the latter mainly represents the areas with frequent earthquakes. The typical case studies show that, for different geological environment backgrounds, by combining the multi geodetic monitoring data with geological, seismic, hydrological data, regional geological environment stability can be effectively monitored and evaluated. Monitoring and evaluating the regional geological environment stability has been expanding the geodetic applications in global change monitoring, and this work is of important scientific and practical significance.
    Research Progress of VLBI Global Observing System (VGOS)
    SUN Zhongmiao, FAN Haopeng
    2017, 46(10):  1346-1353.  doi:10.11947/j.AGCS.2017.20170326
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    Known for unique super-high spatial resolution and positioning accuracy, very long baseline interferometry (VLBI) has been a geodetic research hotspot in various countries since late 1970s. The measuring capability of VLBI currently, however, still stays below satisfaction to a number of scientific and engineering fields, which require millimeter-level accuracy. In order to realize the goal of 1 mm positioning accuracy on global scales, the international VLBI service for geodesy and astrometry(IVS)recommended constructing a new generation VLBI observing system, namely VGOS. Starting with subsystems that constitute a VGOS station, this paper introduced the present progress and development trend of VGOS at home and abroad, and finally listed the problems and challenges which still should be faced at present stage.
    Research and Evaluation of BDS Real-time Wide-area Precise Positioning Service System
    SHI Chuang, ZHENG Fu, LOU Yidong
    2017, 46(10):  1354-1363.  doi:10.11947/j.AGCS.2017.20170284
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    By adopting the real-time observations of IGS, multi-GNSS experiment (MGEX) and national BDS augmentation service system (NBASS), BDS real-time wide-area precise positioning service system is developed, which can generate high accuracy BDS real-time orbits, clocks and ionosphere products and provide centimeter-, decimeter-and meter-level positioning service with different positioning modes including BDS dual-and single-frequency precise point positioning (PPP) and single point positioning (SPP). The evaluation results of real-time products show that the user range error (URE) of BDS real-time orbits and clocks is about 2.0 cm and the accuracy of real-time ionosphere products is better than 4.0 TECU. The performance of real-time kinematic positioning at the 95% confidence level is evaluated by real-time stations across China. It reveals that the BDS dual-frequency PPP shows significant regional characteristic, the accuracy in high-latitude and western fringe region is about 0.2 m and 0.3 m in the horizontal and vertical component, respectively, while the horizontal accuracy is better than 0.1 m and the vertical accuracy is better than 0.2 m in the midlands, which is close to the accuracy of GPS real-time PPP. By the combination of BDS and GPS, the BDS/GPS PPP can improve the positioning performance of GPS or BDS PPP, especially improves the PPP convergence time significantly and the convergence time is within 20 min. In addition, except the fringe region, BDS single-frequency PPP can achieve 0.5 m in horizontal component and 1.0 m in vertical component, BDS SPP can achieve 2.0 m and 3.0 m in horizontal and vertical components, respectively.
    Research Progress of Precise Models and Correction for GNSS Ionospheric Delay in China over Recent Years
    YUAN Yunbin, HUO Xingliang, ZHANG Baocheng
    2017, 46(10):  1364-1378.  doi:10.11947/j.AGCS.2017.20170349
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    The ionosphere effects account for one of the most challenging error sources that can severely affect the performance of Global Navigation Satellite System (GNSS) applications. In the past a few decades, owing to the fact that the ground-and space-based GNSS data are rapidly growing, many researchers have developed and presented a series of theories, methods and techniques to weaken or eliminate the impact of ionospheric delay on GNSS user navigation and positioning, and achieved a number of important achievements and progress. In this paper, a brief review is made towards study on GNSS ionospheric delay correction in China over recent years, with special attention focused on accurate extraction of ionospheric delay, modeling TEC and error analysis, and real-time ionospheric delay correction methods.
    Challenges and Opportunities of GNSS Reference Station Network
    JIANG Weiping
    2017, 46(10):  1379-1388.  doi:10.11947/j.AGCS.2017.20170424
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    GNSS(Global Navigation Satellite System) reference station network is not only an important infrastructure to provide national, regional and global high-precision time and space datum, but also is an important support for navigation and location services, precise satellite orbit determination, geological disaster monitoring and other scientific and technological applications. At present, with the increase of reference station network of continuously operating reference system (CORS) and the rapid establishment of BeiDou, the development of the networks is facing many opportunities and challenges. Firstly, this paper gives the definition and classification of the GNSS reference station network, and describes its function and significance. And then the history and present situation of development of the network are analyzed. Finally, we discuss the challenges and opportunities of the network based on its establishment, data processing theory and method, application.
    New Progress and Application Prospects of Global Navigation Satellite System Reflectometry (GNSS+R)
    JIN Shuanggen, ZHANG Qinyun, QIAN Xiaodong
    2017, 46(10):  1389-1398.  doi:10.11947/j.AGCS.2017.20170282
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    The Global Navigation Satellite System (GNSS) has the characteristics with all-weather, near real-time and high precision observations. It can transmit L band signals continuously, which has been widely used in positioning, navigation and timing (PNT). With the development of GNSS technology, recently GNSS reflected signals can be used to detect Earth's surface characteristics, i.e., GNSS reflectometry (GNSS+R). Combined with GNSS receiver antenna position and medium information, surface roughness and characteristics can be determined by using delay measurements. As a hotspot in GNSS and remote sensing field, GNSS+R has achieved a number of progress and results. In this paper, the principles and methods of GNSS+R are presented as well as their latest advances, including various techniques, methods and remote sensing applications in the ocean, land, hydrological, vegetation and ice and snow, especially the latest progresses in BeiDou-R and TDS-1 GNSS+R. Finally, the future applications and prospective of GNSS+R are given, including multi-GNSS system, new GNSS-R receivers, GNSS+R missions and emerging applications.
    Review of GNSS PPP and Its Application
    ZHANG Xiaohong, LI Xingxing, LI Pan
    2017, 46(10):  1399-1407.  doi:10.11947/j.AGCS.2017.20170327
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    In this paper, we summarized the development of precise point positioning (PPP)technologies and its applications. Key technologies and methodologies for PPP float solution, ambiguity-fixing PPP, real-time PPP and multi-GNSS PPP were intensively analyzed and discussed. Typical PPP applications were summarized and demonstrated. Finally, we illustrated the prospect of PPP and pointed out problems to be solved for PPP development and applications in the coming years.
    Research Progress and Prospect of GNSS Space Environment Science
    YAO Yibin, ZHANG Shun, KONG Jian
    2017, 46(10):  1408-1420.  doi:10.11947/j.AGCS.2017.20170333
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    Troposphere and ionosphere are two important components of the near-earth space environment. They are close to the surface of the earth and have great influence on human life. The developments of Global Navigation Satellite System (GNSS) over the past several decades provide a great opportunity for the GNSS-based space environment science. This review summarizes the research progress and prospect of the GNSS-based research of the Earth's troposphere and ionosphere. On the tropospheric perspective, modeling of the key tropospheric parameters and inversion of precipitable water vapor (PWV) are dominant researching fields. On the ionospheric perspective, 2D/3D ionospheric models and regional/global ionospheric monitoring are dominant researching fields.

    Urban Infrastructure Health Monitoring with Spaceborne Multi-temporal Synthetic Aperture Radar Interferometry
    LIN Hui, MA Peifeng, WANG Weixi
    2017, 46(10):  1421-1433.  doi:10.11947/j.AGCS.2017.20170339
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    Synthetic aperture radar interferometry (InSAR) is a well developed earth observation technology in the last two decades. It can measure minute movements and digital elevation model with high accuracy over large areas by inteferometric processing of two SAR images. In particular, multi-temporal InSAR (MT-InSAR) can achieve centimetric to millimetric deformation monitoring by properly removing atmospheric delay using multiple SAR images. This paper gives a review of current cutting-edge MT-InSAR algorithms. The focus is on the key technologies of MT-InSAR and the primary application fields for urban infrastructural health monitoring. Finally, we give some suggestions for the future development of this technology.
    Remote Sensing:From Trained Professionals to General Public
    SHAN Jie
    2017, 46(10):  1434-1446.  doi:10.11947/j.AGCS.2017.20170361
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    Influenced by the growing popularity of smart phones and the rapid development of open science, remote sensing is being developed and applied more by general public than by trained professionals. This trend is mainly embodied in the democratized data collection, democratized data processing and democratized data usage. This paper discusses and analyzes the three aforementioned characteristics, introduces some recent representative work and progress. It also lists numerous international open data processing tools, including photogrammetry processing, laser scanning processing, machine learning, and spatial information management. In addition, the article makes a detailed description of the benefits of open data, and lists a number of global data programs and experimental data sets for scientific research. At the end of this paper, it is pointed out that the democratization of remote sensing will not only produce great economic benefits, but also bring about great social benefits, and finally change the landscape of industry and the life style of people.
    Advance and Future Development of Change Detection for Multi-temporal Remote Sensing Imagery
    ZHANG Liangpei, WU Chen
    2017, 46(10):  1447-1459.  doi:10.11947/j.AGCS.2017.20170340
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    Change detection in multi-temporal remote sensing images can be widely applied in monitoring ecosystem changes,and tracking urban developments,thus is extremely useful to study the interaction between human and natural environment.With the development of new remote sensing technology,change detection has attracted more and more interests in dealing with multi-temporal hyperspectral and high-resolution remote sensing images.In this review,the recent advances are introduced in four aspects:pre-processing,change detection method,thresholding and accuracy assessment.Then,the main applications for change detection are summarized.And finally,the future developments of change detection are discussed.
    Advances and Prospects of Information Extraction from Point Clouds
    ZHANG Jixian, LIN Xiangguo, LIANG Xinlian
    2017, 46(10):  1460-1469.  doi:10.11947/j.AGCS.2017.20170345
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    Point cloud is one type of the widely used data sources in many communities such as photogrammetry, remote sensing, and computer vision etc. Moreover, information extraction is a necessary step in the process of point cloud processing, analysis and applications. As result, the scholars have proposed a great number of methods for point cloud information extraction. According to the three view points of primitive types, extracted features, and methods for feature selection and classification, this review paper summarizes the research status of point cloud information extraction. This paper also point out five main problems and six main trends in point cloud information extraction, especially introduces a new paradigm:fusion of multiple primitives for point cloud information extraction.
    Progress in Analysis to Remote Sensed Thermal Abnormity with Fault Activity and Seismogenic Process
    WU Lixin, QIN Kai, LIU Shanjun
    2017, 46(10):  1470-1481.  doi:10.11947/j.AGCS.2017.20170347
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    Research to the remote sensed thermal abnormity with fault activity and seismogenic process is a vital topic of the Earth observation and remote sensing application. It is presented that a systematic review on the international researches on the topic during the past 30 years, in the respects of remote sensing data applications, anomaly analysis methods, and mechanism understanding. Firstly, the outlines of remote sensing data applications are given including infrared brightness temperature, microwave brightness temperature, outgoing longwave radiation, and assimilated data from multiple earth observations. Secondly, three development phases are summarized as qualitative analysis based on visual interpretation, quantitative analysis based on image processing, and multi-parameter spatio-temporal correlation analysis. Thirdly, the theoretical hypotheses presented for the mechanism understanding are introduced including earth degassing, stress-induced heat, crustal rock battery conversion, latent heat release due to radon decay as well as multi-spheres coupling effect. Finally, three key directions of future research on this topic are proposed:anomaly recognizing by remote sensing monitoring and data analysis for typical tectonic activity areas; anomaly mechanism understanding based on earthquake-related earth system responses; spatio-temporal correlation analysis of air-based, space-based and ground-based stereoscopic observations.
    Technology and Applications of Surveying and Mapping for ZY-3 Satellites
    TANG Xinming, WANG Hongyan, ZHU Xiaoyong
    2017, 46(10):  1482-1491.  doi:10.11947/j.AGCS.2017.20170251
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    This paper systematically summarizes the research and development of technology and product since the launch of the ZY-3 surveying and mapping satellite,as well as the data application.Based on the introduction about satellite system technical parameters,this paper describes the processing methods about radiation correction,attitude post-processing,geometric calibration and imaging geometric model,and introduces the project realization in the past 5 years.The application of the data is summarized and analyzed,and the development prospect of the mapping satellite is briefly expected.
    Research Status and Prospect of Spatiotemporal Fusion of Multi-source Satellite Remote Sensing Imagery
    HUANG Bo, ZHAO Yongquan
    2017, 46(10):  1492-1499.  doi:10.11947/j.AGCS.2017.20170376
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    High spatial resolution monitoring of land surface and atmospheric environment dynamics requires high spatiotemporal resolution satellite remote sensing imagery as data support. However, the efficient, low-cost, and feasible solution is to blend the multi-source images with high-spatial and high-temporal resolution respectively to produce the desired high spatiotemporal resolution imagery required by different research or applications, which is subject to the limitations of satellite sensor' hardware technology and the budget constraints of launching more satellites. Although plenty of spatiotemporal image fusion research has been conducted, they are limited to specific data types, algorithm principles, application purposes, etc. Furthermore, the development of spatiotemporal image fusion algorithm presents a phenomenon of disorder. This study summarizes and generalizes the existing mainstream spatiotemporal fusion methods and classified them into four categories:①spatiotemporal fusion based on land components; ②spatiotemporal fusion based on spatial information; ③spatiotemporal fusion based on temporal changes; ④combined spatiotemporal fusion. Meanwhile, the study analyzes the problems and challenges faced by spatiotemporal fusion; and informs the prospects of the future development of spatiotemporal fusion method.
    Essential Technology and Application of Jitter Detection and Compensation for High Resolution Satellites
    TONG Xiaohua, YE Zhen, LIU Shijie
    2017, 46(10):  1500-1508.  doi:10.11947/j.AGCS.2017.20170384
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    Satellite jitter is a common and complex phenomenon for the on-orbit high resolution satellites, which may affect the mapping accuracy and quality of imagery. A framework of jitter detection and compensation integrating data processing of multiple sensors is proposed in this paper. Jitter detection is performed based on multispectral imagery, three-line-array imagery, dense ground control and attitude measurement data, and jitter compensation is conducted both on image and on attitude with the sensor model. The platform jitter of ZY-3 satellite is processed and analyzed using the proposed technology, and the results demonstrate the feasibility and reliability of jitter detection and compensation. The variation law analysis of jitter indicates that the frequencies of jitter of ZY-3 satellite hold in the range between 0.6 and 0.7 Hz, while the amplitudes of jitter of ZY-3 satellite drop from 1 pixel in the early stage to below 0.4 pixels and tend to remain stable in the following stage.
    Progress, Challenges and Perspectives of 3D LiDAR Point Cloud Processing
    YANG Bisheng, LIANG Fuxun, HUANG Ronggang
    2017, 46(10):  1509-1516.  doi:10.11947/j.AGCS.2017.20170351
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    3D LiDAR can perform an intensive sampling of the earth surface in a direct way, and yield the 3D point cloud that contains numerous and scattered points with the coordinates (X, Y, Z) and attributes (e.g., intensity). As the vital 3D geospatial data for description of the world in the digital era, 3D point cloud plays an important role not only in earth science researches but also in national requirements (e.g., global change analysis, global mapping, and smart city). Inspired by sensor technologies and national requirements, 3D LiDAR has got great progresses in hardware, data processing and applications, and is facing new challenges. Following the history of 3D LiDAR, this paper first reviews the status of 3D LiDAR system, and introduces the development of key technologies in data processing. Then the typical applications of 3D LiDAR in surveying and other related fields are listed, and current challenges in point cloud processing are concluded. Finally, some future perspectives are presented.
    Retrospect and Prospect of the Development of Chinese Cartography
    LIAO Ke
    2017, 46(10):  1517-1525.  doi:10.11947/j.AGCS.2017.20170330
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    This paper is divided into three parts. The first part of the article is a brief review of the developmental history of ancient and modern cartography in China. It shows that China is one of the earliest countries in the world to create maps. China played an important role in the development of cartography in the world, and has made significant contributions to the development of cartography. Up till the Ming Dynasty in 15th Century, China's map and cartography had always been ahead of the Western countries, but fell behind only after the Qing Dynasty. The second part of the article describes the rapid development of China's mapping and cartography after the founding of the "New China", including the tremendous achievements in the areas of mapping and creation of national topographic maps, thematic maps and atlases, remote sensing cartography, computer-aided cartography, multimedia electronic maps, mobile communication maps, online maps, and theoretical research of cartography. China has caught up and reached the world's advanced level in cartography. The third part It proposes the direction and adjusted roles of mapping and cartography in China in the new century, and analyzes the opportunities, challenges and prospects of cartography in the era of big data, internet and artificial intelligence. Via visualization of 3D dynamic mapping, big data can show the spatial pattern and regional differentiation as well as temporal and spatial dynamic change of subjects and phenomena, and then make analysis and evaluation, forecast and early warning, zoning and layout, planning and design, management and regulation. Therefore cartography can play an important role in the era of big data. In the future, internet will become the main platform for map creation and application. Maps will be more popular, personalized, intelligent and practical.
    Research Progress of Global Land Domain Service Computing:Take GlobeLand 30 as an Example
    CHEN Jun, WU Hao, LI Songnian
    2017, 46(10):  1526-1533.  doi:10.11947/j.AGCS.2017.20170411
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    Combining service-computing technology with domain requirements is one of the important development directions of geographic information under Internet+, which provides highly efficient technical means for information sharing and collaborative services. Using GlobeLand 30 as an example, this paper analyzes the basic problems of integrating land cover information processing and service computing, introduces the latest research progress in domain service modeling, online computing method and dynamic service technology, and the GlobeLand 30 information service platform. The paper also discusses the further development directions of GlobeLand 30 domain service computing.
    Towards a Scale-driven Theory for Spatial Clustering
    LI Zhilin, LIU Qiliang, TANG Jianbo
    2017, 46(10):  1534-1548.  doi:10.11947/j.AGCS.2017.20170275
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    Spatial clustering plays a key role in exploratory geographical data analysis. It is important for investigating the distribution of geographical phenomena. Spatial clustering sometimes also serves as an important pre-processing for other geographical data analysis techniques. Although lots of attentions have been paid to spatial clustering, two serious obstacles remain to be tackled:①clusters will always be discovered in any geographical dataset by spatial clustering algorithms, even if the input dataset is a random dataset; ②users feel difficult to interpret the various clustering results obtained by using different parameters. It is hypothesized that scale is not handled well in clustering process. As a result, a scale-driven theory for spatial clustering is introduced in this study, based on the human recognition theory and the natural principle of multi-scale representation. Scale is modeled as parameter of a clustering model, and the scale dependency in spatial clustering is handled by constructing a hypothesis testing, and multi-scale significant clusters can be easily discovered by controlling the scale parameters in an objective manner.
    Surveying and Mapping Geographical Information from the Perspective of Geography
    LÜ Guonian, YUAN Linwang, YU Zhaoyuan
    2017, 46(10):  1549-1556.  doi:10.11947/j.AGCS.2017.20170338
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    It briefly reviewed the history of geographic information content development since the existence of geographic information system. It pointed out that the current definition of geographic information is always the extension from the "spatial+ attributes" basic mapping framework of geographic information. It is increasingly difficult to adapt to the analysis and application of spatial-temporal big data. From the perspective of geography research subject and content, it summarized systematically that the content and extension of the "geographic information" that geography needs. It put forward that a six-element expression model of geographic information, including spatial location, semantic description, attribute characteristics, geometric form, evolution process, and objects relationship.Under the guidance of the laws of geography, for geographical phenomenon of spatial distribution, temporal pattern and evolution process, the interaction mechanism of the integrated expression, system analysis and efficient management, it designed that a unified GIS data model which is expressed by six basic elements, a new GIS data structure driven by geographical rules and interaction, and key technologies of unstructured spatio-temporal data organization and storage. It provided that a theoretical basis and technical support for the shift from the surveying and mapping geographic information to the scientific geographic information, and it can help improving the organization, management, analysis and expression ability of the GIS of the geographical laws such as geographical pattern, evolution process, and interaction between elements.
    Research Progress in Mathematical Analysis of Map Projection by Computer Algebra
    BIAN Shaofeng, LI Houpu, LI Zhongmei
    2017, 46(10):  1557-1569.  doi:10.11947/j.AGCS.2017.20170396
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    Map projection is an important component of modern cartography, and involves many fussy mathematical analysis processes, such as the power series expansions of elliptical functions, differential of complex and implicit functions, elliptical integral and the operation of complex numbers. The derivation of these problems by hand not only consumes much time and energy but also makes mistake easily, and sometimes can not be realized at all because of the impossible complexity. The research achievements in mathematical analysis of map projection by computer algebra are systematically reviewed in five aspects, i.e., the symbolic expressions of forward and inverse solution of ellipsoidal latitudes, the direct transformations between map projections with different distortion properties, expressions of Gauss projection by complex function, mathematical analysis of oblique Mercator projection, polar chart projection with its transformation. Main problems that need to be further solved in this research field are analyzed. It will be helpful to promote the development of map projection.
    Progress of Digital Terrain Analysis on Regional Geomorphology in China
    TANG Guoan, NA Jiaming, CHENG Weiming
    2017, 46(10):  1570-1591.  doi:10.11947/j.AGCS.2017.20170388
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    Regional geomorphological research is an important part of regional geography research. In recent decades, digital terrain analysis has been widely used in regional geomorphology research. However, due to the limitations of the classic neighborhood analysis algorithm, it is hard to realize the quantitative analysis on the macroscopic morphological features. To solve this problem, Chinese scholars had made a lot of explorations and innovations. An overall review was made in this paper on Chinese scholars' contribution to the DTA research on macro terrain morphology analysis, topographic feature analysis, tupu analysis, landform evolution, landform classification and mapping. The research review shows that Chinese scholars' researches are closely followed by international frontier. The digital terrain analysis in the Qinghai-Tibet Plateau, the Loess Plateau and the southwest karst area highlights the regional characteristics and advantages of geomorphology in China, and has had an important impact in the international academic session.

    Mobile Mapping,Geographic Information Update and Urban Management Intelligence
    LU Xiushan, TENG Teng, LIU Rufei
    2017, 46(10):  1592-1597.  doi:10.11947/j.AGCS.2017.20170328
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    The foundation of urban management intelligence is internet,geographic information platform and cloud computing platform.Data updating is the soul of geographic information platform.The rapid updating of urban geographic information involves concepts,funds and techniques.These three factors constitute the historic challenge of urban surveying and mapping,and also the reality bottleneck of the implementation of urban management intelligence.This paper presents a city natural data model(CNDM)that is based on the color laser point cloud.Based on vehicle borne mobile mapping,unmanned aerial vehicle (UAV) aerial photograph,mobile phone taking,HD video surveillance and cloud computing platform,a fast updating system of CNDM is formed.City geographic information platform for city actuality is constructed based on the real-time update of CNDM,which is to establish the base data of urban management intelligence.
    Geographical Simulation and Optimization System (GeoSOS) and Its Application in the Analysis of Geographic National Conditions
    LI Xia, LI Dan, LIU Xiaoping
    2017, 46(10):  1598-1608.  doi:10.11947/j.AGCS.2017.20170355
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    Since the Chinese first survey on geographic national conditions has completed, an urgent need is to analyze these geographical data, such as mining of spatial distribution patterns, land use transition rules, development trends. The analysis is crucial for extracting the knowledge from these big data about geographic national conditions. The remote sensing interpretation data and land use/cover data generated by these geographic national conditions monitoring projects are the basic data sources for a variety of research and applications in terms of land use change detection, urban dynamic analysis, and urban/land use planning. The information can be used for assisting in the coordination of land resource use and decision making for urban and rural development, ecological environment protection and other issues that depends on spatial intelligent decisions. We proposed the theoretical framework of geographical simulation and optimization system (GeoSOS), which coupled geographic process simulation/prediction and spatial optimization, provides powerful theoretical support and practical tools for above researches. This paper develops the extension of GeoSOS software-GeoSOS for ArcGIS, which is an ArcGIS Add-In runs on ArcGIS platform for facilitating the above analyses. We take the urban expansion and ecological protection research in rapid urbanization area as an example, use the software to tackle a series of urbanization issues in the study area. The simulation results show that the predicted land development intensity of Guangdong Province will exceed the constraint index in 2020 according to the national development plan. However, the urbanization expansion based on the constraints of land development intensity and ecological protection can satisfy these constraints, and obtain a more compact landscape pattern. The analysis has shown that GeoSOS can be a useful tool for assisting in the analysis of geographic national conditions information. The paper also provides some useful guidelines for these analysis and the future research directions.
    Research Progresses in Digital Watermarking and Encryption Control for Geographical Data
    ZHU Changqing
    2017, 46(10):  1609-1619.  doi:10.11947/j.AGCS.2017.20170301
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    With the rapid growth in application and requirement for sharing geographical data, the problem of geographical data security arises prominently. The security of geographical data not only affects the healthy development of the geographical information industry, but also has connections construction of national defense and national security. Digital watermarking and encryption control techniques have become frontier techniques and effective solutions for achieving protection of geographical data. Recently, the research and application of digital watermarking techniques have experienced fast development. In this study, the research background and requirements of digital watermarking and encryption control is introduced. In addition, this paper analyzes and evaluates their theories, models and research progresses and discusses the related software development and application status. Finally, the future routes of theoretical research and applications of digital watermarking are prospected based on the developing trend of geographic information industry and information techniques.
    Reliability Analysis in Geographical Conditions Monitoring
    SHI Wenzhong, CHEN Pengfei, ZHANG Xiaokang
    2017, 46(10):  1620-1626.  doi:10.11947/j.AGCS.2017.20170377
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    Reliability is one of the most important theoretical problems in geographical conditions monitoring. In this paper, it presented that the research on the reliability of geographical conditions monitoring was based on the theory of spatial data reliability. First, it reviewed and analyzed the theory of spatial data reliability. The scope of reliability of geographical conditions monitoring data is defined. Secondly, it proposed the framework of the reliability evaluation of the monitoring data, and it identified the contents, indicators, and process of the reliability evaluation correspondingly. Then, it introduced the application of the above theoretical results on overall reliability evaluation of the resultant data from the First National Geographical Survey. Finally, some prospects for future research on the reliability of geospatial data were given.
    Research on the Progress of Multi-sources Geospatial Vector Data Fusion
    SUN Qun
    2017, 46(10):  1627-1636.  doi:10.11947/j.AGCS.2017.20170387
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    Geospatial vector data plays a crucial role in the national economy and the construction of the national defense modernization for it's not only the important component of human social and geographical environment information, but also a key carrier of relevant social information. The technology of the multi-source geospatial vector data fusion is a valid method of solving the inconsistency questions of the multi-source data in geometric position, attribute feature, etc. In recent years, its relevant technology as well as its application also has deeply developed. Based on the analysis of the questions in the application of the two-dimensional geospatial vector data are facing, the research status of the theory, algorithm and technologies of geometric feature fusion and attribute feature fusion of the two-dimensional geospatial vector data are overviewed and evaluated, with the current research status, whose theory and application of the future focus of research are looked forward to in this paper.
    The Constancy and Volatility in Cartography
    MENG Liqiu
    2017, 46(10):  1637-1644.  doi:10.11947/j.AGCS.2017.20170359
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    Being facilitated by a number of scientific and technological revolutions,maps have successively evolved from omnipotent rare treasures to omnipresent daily necessities,but cartography remains a unique mixture of science,art and technology of making and using maps.This paper revisits four persistent research questions in cartography:①what is a map, ②for what is a map worth,③how are maps made, and ④who is making maps, Based on a retrospective analysis of cartographic progresses with regard to the map typology,values of maps,mapmaking workflows and the role of mapmaker,the author exemplifies the constants and variables in the development processes since the introduction of computer in the 1970's and indicates the emerging trend towards a sustainable mapping ecosystem supported by cloud computing platforms.
    Overview of the Research Progress in Automated Map Generalization
    WU Fang, GONG Xianyong, DU Jiawei
    2017, 46(10):  1645-1664.  doi:10.11947/j.AGCS.2017.20170287
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    Spatial information generalization is a major issue in spatial information processing. This paper reviews the research development of cartographic generalization in generalization knowledge category and acquiring, operator and algorithm, quality evaluation and process modeling and controlling. The paper analyzes cartographic generalization in the background of big data, and puts forward that the cartographic generalization should revise the research object, the concept and the method.

    Key Techniques and Project Practice for Establishing National Geo-information Service Platform “Tianditu”
    JIANG Jie, WU Huayi, HUANG Wei
    2017, 46(10):  1665-1671.  doi:10.11947/j.AGCS.2017.20170357
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    Web-based geographic information service is the important manner for public service of geographic information in the information age. In January 2011, the National Administration of Surveying, Mapping and Geoinformation released the National Geo-information Service Platform "Tianditu", which effectively promoted the sharing and extensive application of the distributed geographic information resources around the country. This paper introduced the construction background, key technologies, and application effect of "Tianditu". And further efforts were discussed in the end of the paper.
    The Review of Visual Analysis Methods of Multi-modal Spatio-temporal Big Data
    ZHU Qing, FU Xiao
    2017, 46(10):  1672-1677.  doi:10.11947/j.AGCS.2017.20170286
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    The visual analysis of spatio-temporal big data is not only the state-of-art research direction of both big data analysis and data visualization, but also the core module of pan-spatial information system. This paper reviews existing visual analysis methods at three levels:descriptive visual analysis, explanatory visual analysis and exploratory visual analysis, focusing on spatio-temporal big data's characteristics of multi-source, multi-granularity, multi-modal and complex association.The technical difficulties and development tendencies of multi-modal feature selection, innovative human-computer interaction analysis and exploratory visual reasoning in the visual analysis of spatio-temporal big data were discussed. Research shows that the study of descriptive visual analysis for data visualizationis is relatively mature.The explanatory visual analysis has become the focus of the big data analysis, which is mainly based on interactive data mining in a visual environment to diagnose implicit reason of problem. And the exploratory visual analysis method needs a major break-through.
    Progresses and Prospects in Geospatial Big Data for E-government
    LIU Jiping, ZHANG Fuhao, XU Shenghua
    2017, 46(10):  1678-1687.  doi:10.11947/j.AGCS.2017.20170320
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    In recent years, geospatial big data have attracted great attention from industry, academia, research and government sectors, and even have triggered a lot of industry changes. Geospatial big data for E-government provide new means for government information management and decision making. This paper analyzes the concepts and characteristics of geospatial big data for E-government, mainly reviews the key technologies in geospatial big data for E-government, including data integration, storage and management, data mining and analysis, visualization, and decision support service technologies. Finally, the bottleneck problems and technical challenges of geospatial big data for E-government are discussed.
    Integrated Representation Geographical Model and Self-compensation Method for Entity and Symbol
    LI Chengming, WU Pengda, YIN Jie
    2017, 46(10):  1688-1697.  doi:10.11947/j.AGCS.2017.20170221
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    Since the concept was proposed at the beginning of last century, cartography generalization has been gradually changed from full manual operation mode to computer automation mode after decades of improvement and development. However, the level of map automation is still relatively low until now. So, this paper puts forward an integrated representation of geographical model for entity and symbol on the basic of innovative model units and spatial relation model. Then the automatic methods of topological compensation for model entity and cartography compensation for model symbolization are established, we want to explore a solution to solve the worldwide problem of automatic cartography generalization. Finally, this paper look into the future and developmental direction of automatic cartography generalization.
    Key Technologies and Applications of Satellite and Sensor Web-coupled Real-time Dynamic Web Geographic Information System
    CHEN Nengcheng, XIAO Changjiang, LI Liangxiong
    2017, 46(10):  1698-1704.  doi:10.11947/j.AGCS.2017.20170311
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    The geo-spatial information service has failed to reflect the live status of spot and meet the needs of integrated monitoring and real-time information for a long time. To tackle the problems in observation sharing and integrated management of space-borne, air-borne, and ground-based platforms and efficient service of spatio-temporal information, an observation sharing model was proposed. The key technologies in real-time dynamic geographical information system (GIS) including maximum spatio-temporal coverage-based optimal layout of earth-observation sensor Web, task-driven and feedback-based control, real-time access of streaming observations, dynamic simulation, warning and decision support were detailed. An real-time dynamic Web geographical information system (WebGIS) named GeoSensor and its applications in sensing and management of spatio-temporal information of Yangtze River basin including navigation, flood prevention, and power generation were also introduced.
    Research Progress and Prospect on Ecological Disturbance Monitoring in Mining Area
    WANG Yunjia
    2017, 46(10):  1705-1716.  doi:10.11947/j.AGCS.2017.20170358
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    Due to the exploitation of resources, serious ecological and environment problem had been aroused in the mining area. Monitoring and analyzing various typical signals and anomalies in the ecological environment of the mining area had become an important basis for environmental protection and ecological restoration. The research progress had been reviewed from such aspects as ground deformation and subsidence, underground coal fire and spontaneous combustion of coal gangue and other ecological disturbance factors monitoring. For the particularity, complexity and highly dynamic of mining subsidence and ecological environment change, the single monitoring method is not enough, integrating the aerospace-borne and ground based integrated earth observation sensor Web and mine Internet of Things, to develop multi-source and multi-scale aerospace-borne and ground based cooperative monitoring and intelligent sensing system for ecological disturbance is the future research focus and direction in mining area.
    Research Progress and Methods of InSAR for Deformation Monitoring
    ZHU Jianjun, LI Zhiwei, HU Jun
    2017, 46(10):  1717-1733.  doi:10.11947/j.AGCS.2017.20170350
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    Deformation monitoring is one of the most mature applications of space-borne InSAR technique. Firstly, we introduce the basic principle of InSAR in the monitoring of deformation and the current SAR satellites. The deformation monitoring methods of InSAR are then classified into the groups of D-InSAR, PS-InSAR, SBAS-InSAR, DS-InSAR and MAI, which are analyzed in the aspects of technical features and application scopes. Subsequently, we analyze the research progress and deficiencies of InSAR in the investigation of urban, mining area, earthquake, volcano, infrastructure, glacier, permafrost and landslide. Finally, some advanced academic problems such as deformation monitoring in multi-demension and low coherence area, atmospheric and orbital errors mitigation, and accuracy assessment are concluded.
    Progress on Dynamic and Precise Engineering Surveying for Pavement and Track
    LI Qingquan, MAO Qingzhou
    2017, 46(10):  1734-1741.  doi:10.11947/j.AGCS.2017.20170323
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    The traditional precise engineering surveying is characterized by manual static discrete observation and geometric model solution,which cannot meet the requirements of large-scale infrastructure such as pavement and track,where need of wide-range,continuous,dynamic and high-precision surveying for these infrastructures' and systems' maintenance and management.The dynamic surveying based on multi-sensor integration technology and the cooperative computing based on multi-source spatial-temporal data are the important development directions for precise engineering surveying.First,the paper introduced the uniform and conversion of high-precision spatial-temporal datum,the multi-sensor synchronous control,the fusion of the observed data,the quality improvement of the surveying data and the feature extraction and recognition of the pavement cracks based on the three-dimensional image.Then,the progress of dynamic and precise surveying applications such as pavement roughness,rutting and deflection survey,as well as geometrical parameters of track,fastener status and rail damage detection are described.
    The Development of Precise Engineering Surveying Technology
    LI Guangyun, FAN Baixing
    2017, 46(10):  1742-1751.  doi:10.11947/j.AGCS.2017.20170313
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    With the construction of big science projects in China, the precise engineering surveying technology developed rapidly in the 21th century. Firstly, the paper summarized up the current development situation for the precise engineering surveying instrument and theory. Then the three typical cases of the precise engineering surveying practice such as accelerator alignment, industry measurement and high-speed railway surveying technology are focused.
    The Review of Development of Marine Surveying Technology
    ZHAI Guojun, HUANG Motao
    2017, 46(10):  1752-1759.  doi:10.11947/j.AGCS.2017.20170309
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    The review of marine surveying technology is made in the aspects of the mingling of discipline, bathymetry and coastal topographic surveying, marine gravity surveying and geomagnetic surveying, and the application of marine survey information. The appearance of new branch of study, the establishment of surveying platform, the development of surveying equipment, the application of new theory, new technology, new method and the surveying information are reviewed. The future development trend of marine surveying is briefly presented.
    Technical Progress in Research of Multibeam Synthetic Aperture Sonar
    LI Haisen, WEI Bo, DU Weidong
    2017, 46(10):  1760-1769.  doi:10.11947/j.AGCS.2017.20170410
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    Recently, detailed underwater target detection and imaging sonar technology has become a research hotpot with the urgent need of marine research. Multibeam synthetic aperture sonar technology has been proposed combining the both technological advantages in this paper, owing to the emphatically analyses of the technology trends of multibeam bathymetric sonar and synthetic aperture sonar. The research progress in the key technologies of multibeam synthetic aperture sonar has been discussed in this paper, the effectiveness of multibeam synthetic aperture sonar detection mechanism is preliminary verified by the experiments. The potential that the multibeam synthetic aperture technique can effectively enhance the underwater target resolution has aslo been proved through the contrast experiment.
    Progress and Prospects in Developing Marine Vertical Datum
    ZHOU Xinghua, FU Yanguang, XU Jun
    2017, 46(10):  1770-1777.  doi:10.11947/j.AGCS.2017.20170322
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    Marine vertical datum system construction is the basic work of marine surveying. In the 2009-2012, China has preliminarily constructed the transformation and unification of different height/depth datum model in the China Sea of 80 nautical mile. In recent years, this model has been extended to the South China Sea, the western Pacific and the eastern Indian Ocean, and then a seamless vertical datum model in the south and north pole area to the whole world gradually will be constructed in the near future, this is the foundation of supporting the digital ocean construction in China. This paper mainly discusses the research status of marine vertical datum construction which had been carried out in major coastal countries or regions, analyzes the main work and approaches and key technologies in the process of the marine vertical datum system building, and then expounds the achievements and existing problems in the practice of our country marine vertical datum building.
    Technical Progress and Development Directions of Oceanic Spatial Information Datum
    BAO Jingyang, XU Jun, YU Caixia
    2017, 46(10):  1778-1785.  doi:10.11947/j.AGCS.2017.20170371
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    This paper briefly analyzes the basic development and technical situation of oceanic spatial information datum, reviews the main processes of oceanic vertical datum and correlative oceanic tidal study, such as improvement and perfect methods of determining tidal station vertical datum, realizing form of vertical datum controlled by tidal station, effect on maintaining vertical datum by long-term tidal station, oceanic tidal model establishing, and also construction and transformation of tidal datum, and then forecasts the key development directions of oceanic spatial information datum on high-accuracy marine position service, vertical datum and the transferring model refinement and spatial datum application.
    Status and Development Tendency for Seafloor Terrain Measurement Technology
    ZHAO Jianhu, OUYANG Yongzhong, WANG Aixue
    2017, 46(10):  1786-1794.  doi:10.11947/j.AGCS.2017.20170276
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    This paper briefly reviewed the history of seafloor terrain measuring technology,and then detailed the introduced sonar bathymetry based on vessel,airborne laser bathymetry,integrated measurement for coastal topography and three inversion methods for seafloor terrain.That entirely presents the current situation of stereoscopic,efficient,high-accuracy and high-resolution of seafloor topography acquirement.Finally,combined with the future requirements,this paper summarized the core job and development trend in future seafloor terrain measuring field,which includes developing more portable multi-beam system with ultra-wide coverage,high accuracy and resolution,researching more efficient correction model of sound velocity effects,smoothing of bathymetry data and expression of submarine topography.Meanwhile,automatic ship measurement will be an important task mode.Also airborne laser survey,seafloor topography inversion from sonar image and deep-towing measurement has enormous potential in development.