Table of Content

25 December 2020, Volume 0 Issue 12

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A CUDA-based parallel accelerating geographically weighted regression algorithm for big data

LIU Zhentao, YANG Yi, WANG Dongchao, XIE Xiaoyao

2020, 0(12):  1-5.  doi:10.13474/j.cnki.11-2246.2020.0379

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In order to improve calculation speed and reduce memory consumption in traditional GWR, this paper proposes a fast parallel geographically weighted regression (FPGWR) algorithm, which bases on the NVIDIA computed unified device architecture (CUDA) to achieve parallel acceleration of GWR. The FPGWR algorithm finely decomposes the serial process into parallel independent computing modules and optimizes the memory usage model to increase the speed of GWR algorithm. This paper compares the calculation speed of FPGWR and traditional GWR towards simulated and real data. Results show that FPGWR can support a larger sample calculation and effectively increase the calculation speed. In addition, the larger the amount of data, the faster the algorithm presents.

Phase unwrapping method based on discontinuity adaptive markov random fields

ZHOU Lifan, ZHANG Shiqi, XIA Yu, ZHONG Shan, GONG Shengrong

2020, 0(12):  6-10,26.  doi:10.13474/j.cnki.11-2246.2020.0380

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Interferometric synthetic aperture radar (InSAR) technology has been widely applied to digital elevation model (DEM) generation. Phase unwrapping, as one of key procedures in InSAR technique is related directly to the accuracy of DEM reconstruction. However, phase unwrapping method can not estimate the discontinuous phase due to the limitation of the phase continuity assumption, which reduces the accuracy of DEM generation in the mountainous area. To solve this problem, a phase unwrapping method based on discontinuity adaptive MRF (DA-MRF) is proposed in this paper, which can deal with discontinuous phase. Firstly, the energy function of DA-MRF is established which can keep the pixel pairs connected for the continuous phase while make the pixel pairs disconnected for the discontinuous phase adaptively. Then, the graph cuts method is used to optimize the energy function of DA-MRF to obtain the final result. The simulated and real data experiments both demonstrate that the proposed method has more powerful discontinuity persevering ability and is more applicable in DEM generation in the mountainous area, compared with other phase unwrapping methods.

A fusion method of mobile video and geographic scene

ZHAO Weisong, QIAN Jianguo, TANG Shengjun, WANG Weixi, LI Xiaoming, GUO Han

2020, 0(12):  11-16.  doi:10.13474/j.cnki.11-2246.2020.0381

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Quick and accurate understanding of the disaster scene situation is the top priority in the disaster relief process. Usually, drones are used for site surveys when disasters occur, but it is difficult to associate the drone video with the actual geographic scene. To this end, this paper proposes a fusion method of mobile video and geographic scene. This method first uses ASift algorithm with affine invariance to detect feature points, and uses the RANSAC algorithm to iteratively remove noise points to calculate video and geography, optimal scene transformation matrix model parameters. Then the calculated perspective transformation parameters are then applied to the video data to restore the coordinates of the corners of the video. Finally, the corner coordinates of all video frames are obtained by interpolation to achieve an accurate fusion of video and DOM. The experimental results show that the shorter the interval frame that matches the video data, the higher the overall fusion accuracy, the standard deviation of the video and geographic scene fusion by this method is less than 10 m.

Extraction of urban green space with high resolution remote sensing image segmentation

CHEN Zhou, FEI Xianyun, GAO Xiangwei, WANG Xiaoxue, ZHAO Huimin

2020, 0(12):  17-20.  doi:10.13474/j.cnki.11-2246.2020.0382

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Urban green space is an important part of ecological civilization construction, and the extraction of green space information is the basis and premise of urban green space planning and construction. Remote sensing image segmentation is the key step of green space information classification. Selecting appropriate image segmentation method can effectively improve the accuracy of urban green space extraction. The traditional remote sensing segmentation method results in a serious edge jagged phenomenon, which is quite different from the green field boundary, and does not meet the requirements of green space information extraction. In this paper, the high-resolution Worldview image is used as the data source, and the urban green space information is extracted based on the deep learning network DeepLab-v3+. At the same time, the classification accuracy of the proposed algorithm is compared with that of Ostu, MeanShift and FNEA. The results show that: DeepLab-v3 + has the best segmentation performance, its segmentation edge is smooth, and it has a high degree of coincidence with the green field boundary, which can effectively solve the edge jagged problem of traditional segmentation algorithm. Because of the good segmentation effect, it also effectively improves the classification accuracy. Among various segmentation and classification algorithms, the accuracy of DeepLab-v3 + is the highest, reaching 98.01%.

High-precision 3D reconstruction of complex stadium under the laser scanning and UAV integrated control

YANG Jun, WANG Zhipeng, ZHU Kai, LI Shuhong, YAN Shi, HU Chunmei

2020, 0(12):  21-26.  doi:10.13474/j.cnki.11-2246.2020.0383

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In view of the problems in the integrity and accuracy of the external fine modeling of complex stadium, this paper proposes a high-precision modeling method which integrates ground control, ground laser scanning and UAV modeling control. Firstly, a high-precision integrated coordinate system of control, scanning and UAV in the area is established by using special signs. Secondly, the whole adjustment and registration of the area is carried out by combining the control coordinates of the multi station laser scanning point cloud on the ground to generate the high-precision ground point cloud model under the integrated coordinate system. Thirdly, the high-precision top data under the integrated coordinate system is generated by using the UAV data and control points. Finally, fusion of two kinds of data to generate a complete, high-precision and fine model of the object. The experiment shows that the whole adjustment method can achieve high-precision registration of multi-site cloud, and the integrated control can achieve high-precision fusion of heterogeneous data, which solves the problem of high-precision modeling of complex building objects, and has great practical value.

Application of UAV photogrammetry technology in deformation monitoring and storage capacity analysis of landfill site

BAI Jun, DONG Xiujun, CHEN Lijian, ZHANG Xu, XIE Mengyang, YANG Junyu

2020, 0(12):  27-31,117.  doi:10.13474/j.cnki.11-2246.2020.0384

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The rapid monitoring of the spatial change of solid material storage in landfill and the accurate evaluation of the effective storage capacity can provide an important basis for city managers to make scientific decisions and rationally arrange social resources. The photogrammetry technology of UAV has the advantages of flexibility, fast data acquisition and high precision, and has been widely applied in many fields. Taking Changan landfill site in Chengdu in Sichuan province as an example, the researchers use the low-altitude UAV photogrammetry technology to obtain the landfill area image data for one year in a row. The volume variation and deformation characteristics of each area in the landfill reservoir area are analyzed based on the model difference. A storage capacity prediction model is established to study the relationship between the variation value of the storage capacity and the mass of the admission objects, and to predict the actual weight of the solid objects that can be admitted into the landfill area.

Registration for indoor RGB-D point clouds assisted by a quad- configuration target

YANG Haijian, XU Ershuai, CHEN Wenjia, XU Zhihua

2020, 0(12):  32-36.  doi:10.13474/j.cnki.11-2246.2020.0385

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For 3D reconstruction of textureless indoor scenarios, we designed a quad-configuration target to assist pair-wise registration of indoor RGB-D point clouds. In detail, we first detected the quad-configuration target by filtering large curvature points with threshold. Then the target parameters and centers in adjacent point clouds were fitted by the random sample consensus (RANSAC) algorithm, matching the centers of the targets by fitting parameters, and achieving rough registration via rigid transformation with 4 points congruent sets. Next, we iteratively identified the overlapping areas between adjacent point clouds. Finally, we used the optimized overlapping area to fine-tune the rigid parameters between adjacent point clouds. In order to test the usability of our method, we used a Kinect camera to acquire 12 station point clouds for two different indoor scenes, respectively. Experimental results indicated that the root mean square error between adjacent point clouds is less than one point sampling interval, which demonstrated the robustness of the proposed method in indoor scene reconstruction with less texture.

Overall calibration of mobile lidar measurement system based on IGS station networking

GUO Ming, ZHOU Tengfei, WANG Guoli, YAN Bingnan, HUANG Ming

2020, 0(12):  37-41.  doi:10.13474/j.cnki.11-2246.2020.0386

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Aiming at the position and attitude deviations between the laser scanner and the carrier coordinate system in the vehicle-mounted mobile measurement system, a position and attitude calibration method with error correction numbers is proposed based on the combination of conventional feature points and feature surface calibration methods. Use TLS to obtain the overall point cloud model of the vehicle system and the sensor’s inherent geometric properties to obtain the initial value of the relative relationship between the sensors. Based on this, an error correction number is introduced to construct the error correction model. Spherical target and plane reflection mark, the least square method iterative method is used to calculate the optimal solution of the error correction number, so as to achieve rapid sensor calibration. The experimental results show that the method is feasible. After calibration, the absolute accuracy of the point cloud plane and absolute elevation are 0.043 m and 0.072 m, respectively, and the relative accuracy is 0.018 m, which meets the accuracy requirements for data acquisition of mobile measurement systems. Development and application are of great significance.

Rapid determination of BDS inter-satellite-type bias

JIA Chun, CUI Peng, LI Hui, ZHAO Lin, LI Liang

2020, 0(12):  42-45.  doi:10.13474/j.cnki.11-2246.2020.0387

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Owing to inter-satellite-type bias (ISTB) that affects integer ambiguity resolution of BDS real-time kinematic (RTK), rapid ISTB determination method is proposed. This proposed method employs only one carrier phase differential observation between different satellite types to achieve ISTB estimation and calibration, so that it is more universal and simpler for practical applications than the traditional method. The tested results show that the ISTB is relevant to the NH code modulation and the ISTBs of different BDS frequencies are inconsistent. Besides, by comparing performances of BDS-RTK with and without ISTB calibration, the results reflect that ISTB will seriously reduce BDS-RTK positioning accuracy and integer ambiguity resolution performances. Therefore, the rapid and accurate calibration of ISTB can effectively guarantee the high precision and high reliability of the BDS-RTK at the present stage of BDS receiver update.

Multi-source data fusion analysis of land subsidence monitoring

LIU Shengnan, TAO Jun, LU Yinhong

2020, 0(12):  46-49.  doi:10.13474/j.cnki.11-2246.2020.0388

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Land subsidence generally refers to a environmental geological phenomenon of a decline in regional ground elevation, which is caused by the soil compression in the joint action of natural and human factors. At the present, we find both advantages and disadvantages among the different monitoring methods of land subsidence. Changzhou-Wujin area is located in the sedimentation section of Yangtze River Delta. This paper explores the case of Wujin central city land subsidence monitoring project. With analysis, comparison and integration of the multi-source data from different monitoring methods, the result combines the advantages of different methods. It not only better describes the present situation and forecasts the trend of land subsidence, but also provides the more accurate and extensive data base for future land subsidence monitoring.

Inconsistency detection and correction of spatial data using constraint rules of dependent distribution

YANG Min, JIANG Chenjun, LI Ying, CHEN Huan

2020, 0(12):  50-53,70.  doi:10.13474/j.cnki.11-2246.2020.0389

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As one of the basic aspects of spatial data quality, the maintenance of logical consistency plays an important role in fields such as spatial database construction and updating. By comparing with the topologic conflicts existed between homogeneous objects, the consistency problems between heterogeneous objects, such as spatial pattern mismatching, conflicts of semantic relationship, are difficult to be handled. From the view of Tobler’s first law of geography, this study aims to solve inconsistencies of spatial data by introducing the rules of spatial dependent distribution between differentgeographical entities. Firstly, we identify three different spatial dependency situations (i.e. location-sharing, structure-associating, and area-including)and further to obtain the constraint rules from those spatial knowledge.Then, we propose inconsistency detection and correction methods based on the three types of constraint rules. This study recognizes the quality of spatial data from geographic view and obtains the constraint rules using knowledge engineering theory, which are beneficial for extending classic theory ofspatial data quality.

Design for symbolic visual hierarchy of geographic name map—an example of “the Atlas of Chenghai District,Shantou”

XIA Zhujun, JIANG Wenping, XI Daping, ZHANG Dingrao, WANG Ying

2020, 0(12):  54-57,86.  doi:10.13474/j.cnki.11-2246.2020.0390

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The Atlas of Chenghai District,Shantou is an important content of the transformation of the second national toponymic census results. To find out the best symbolic visualization strategy,this paper organized the whole map symbol library using tree model,and then a symbolic visual hierarchy is built which contains three levels including theme and scale,geometric feature,classification set. Visual variables are organically composed to achieve the best map visual perception. As the conclusion,the tree structure of the symbol library and the visual hierarchy can be effectively applied for the symbolization of the geographic name map.

Application of surveying and mapping geographical information technology and data achievement service for territorial and spatial planning

WANG Wei, JIN Xianfeng

2020, 0(12):  58-64.  doi:10.13474/j.cnki.11-2246.2020.0391

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The top-level design of territorial and spatial planning system in the new era, the construction of “four beams and eight pillars” and the future smart territorial and spatial planning need the support of digital and information technology. Surveying and mapping geographic information is good at spatial data acquisition and analysis, which can provide effective technical services and customized services based on data achievement for the construction, approval, implementation, monitoringand evaluation of territorial and spatial planning. “one map” of territorial and spatial planning through the fusion of current situation data, planning data and management data achieves a unified “base map”, a unified “base number”, a unified “bottom line” and a unified “bottom plate”. “one map” information system for implementation and supervision of territorial and spatial planning supports dynamic monitoring, evaluation and early warning of territorial and spatial planning which is an important guarantee for the development of an intelligent, perceptible and self-adaptive territorial and spatial planning. It is characterized by easy learning and good governance. this paper studies the surveying and mapping geographic information service system for territorial and spatial planning from two aspects of technical system and data achievement customization system, and prospects the application of surveying and mapping geographic information for intelligent territorial and spatial planning.

Construction of “A map” of the national territorial space planning based on planning entity

WANG Furong, XU Jiangang, YAO Rongjing, XU Han, MAO Yanling, DOU Wei

2020, 0(12):  65-70.  doi:10.13474/j.cnki.11-2246.2020.0392

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The “A map” of the national territorial space planning is conducive to unifying space land use control, strengthening planning and implementation supervision, promoting data sharing between government departments and information interaction between government and society. Governments at all levels are vigorously carrying out the construction of “A map” of the national territorial space planning. At present, there are many types of planning data. However, there are problems such as unplanned planning data systems, lack of correlation between data, difficulty in integration, and difficulty in updating linkages. Therefore, the paper first proposes the planning entity. Taking the controlled detailed planning and public utilities special planning in Nanjing as the research object, the research on coding system, attributes design of the planning entity and relationship construction is carried out, and it is verified by examples. The research shows that the planning data system based on the planning entity is more scientific, which can effectively realize the association and dynamic update between data, and provides a new construction idea for the construction of “A map” of the national territorial space planning.

Application of real estate big data in spatial evaluation model of urban renewal potential

WANG Yang, TANG Hua, PAN Jin, LI Yang, CHU Qiao, LIU Yuqing

2020, 0(12):  71-74,82.  doi:10.13474/j.cnki.11-2246.2020.0393

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China’s development in the era of new normalcy and refinement of urban governance lift the demand for more accurate policy-making based on quantitative evaluations. While the process of urban renewal is closely related to the interaction of people, land and buildings, real-estate big data, which contains rich information about the people-land-building relationships, may provide a strong support for the quantitative evaluations related to urban renewal. However, few existing evaluation model has yet addressed the usage of this data. This paper proposes an evaluation model of urban renewal potential based on real estate big data. The model is applied to Nanjing on the Jiedao level, demonstrating the model’s ability in identifying Jiedaos’ suitability and directions for urban renewal, which contributes to more accurate policy-making in the urban development process.

Integration of natural resources government service system and data fusion construction: taking Nanjing as an example

CHEN Bo, CUI Bei, DING Xin

2020, 0(12):  75-78.  doi:10.13474/j.cnki.11-2246.2020.0394

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The general plan of information construction formulated by the Ministry of Natural Resources requires the construction of an application system of “Internet plus natural resources administration service” to achieve “unified standards of service matters, overall linkage, business collaboration, and comprehensive improvement of natural resources government services and sharing and opening capabilities”. As the key construction content of government service application system, how to integrate various kinds of data resources and play a systematic role has become an urgent problem. After analyzing the demand of natural resources business management, this paper puts forward the construction idea of integrated government service system and data fusion.

Research on the application of base map based on the results of the third national land investigation

LI Meixiang, TANG Hua, KE Hongjun

2020, 0(12):  79-82.  doi:10.13474/j.cnki.11-2246.2020.0395

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Under the background of ecological civilization construction, natural resource management is facing new requirements and challenges. Focusing on the realization of the “two unifications” of the Ministry of Natural Resources, a unified base map is the basis and prerequisite for carrying out various tasks of the department. The third land investigation is the latest and most comprehensive land investigation since the establishment of the Ministry of Natural Resources, laid a solid foundation for unifying the base map. This paper proposes to carry out the data integration of “basic investigation and special investigation” and “status and management” step by step based on the results of the third land investigation.So as to form an application base map that supports the management of natural resources.

Data integration analysis of forest land survey in Nanjing city

WU Yangqing, TANG Hua, LI Meixiang

2020, 0(12):  83-86.  doi:10.13474/j.cnki.11-2246.2020.0396

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The analysis and integration of the third nationwide land survey and the special natural resources survey results is an important basis for the natural resources management. Taking the forest land survey data integration in Nanjing city as the breakthrough point, this paper carries out the cross-analysis between the third nationwide land survey and the inventory for forest management planning and design, combs and maps the forest land classification standards, develops rules for space conflict, and explores the integration process of forest land survey data, in order to provide reference for constructing “a base map” of natural resources survey.

Three-dimensional reconstruction of irregular cultural relics based on point cloud data: taking Buddhist stone pilar as an example

XI Wenfei, LI Lingsuo, YANG Yong, LI Guozhu, LI Chunmei, LI Jinping

2020, 0(12):  87-89.  doi:10.13474/j.cnki.11-2246.2020.0397

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Massive point cloud data can build 3D modeling of cultural relics very well. For complex surface structure of cultural relics, traditional algorithms are difficult to achieve fine modeling. In order to solve the problem of spatial triangular mesh, the paper combines the normal vector of spatial triangle to construct triangular mesh. Take Kunming cultural relic——Buddhist stone pilar as an example to carry on the three-dimensional reconstruction, the new method in this paper is suitable for 3D modeling of indoor cultural relics and can achieve better results.

An accurate oblique photography models merging method

CHEN Hansheng, LIU Zhendong, WANG Fei, LI Chengming

2020, 0(12):  90-92,100.  doi:10.13474/j.cnki.11-2246.2020.0398

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Existing 3D models merging methods are mostly implemented by re-triangulation vertices of original triangle face, which causes unpleasant results, like geometric feature losing and texture distortion of original 3D models. In this paper, an accurate oblique photography models merging method is proposed based on the characteristics of the oblique photography models. Fistly, a model is selected as center model, and the fusion area is calculated by the spatial relationship between the center model outline boundary and another model. Then the outline boundary of center model is set as constraint and triangles of raw mesh are subdivided accurately. Finally, Texture coordinates is calculated by interpolation of accurate subdivided trianglular face. At the end of this paper, we verify proposed merge method with actual oblique photography data, and the result shows that the merged mesh model of proposed method is topologically correct, and there have no holes, cracks and misalignments on the fusion boundary, and the texture is transitioned naturally and no obvious differences of color exist.

Massive IGS data concurrent acquisition with real-time thread pool

WANG Jianwei, GUO Chunxi, BAI Mu, CHEN Zhao

2020, 0(12):  93-96,105.  doi:10.13474/j.cnki.11-2246.2020.0399

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With the rapid development of global navigation satellite system (GNSS), the international GNSS service (IGS) released high-precision and massive service data. At present, the IGS data have been widely used in GNSS baseline solution, precise point positioning, satellite precise orbit determination, crustal deformation monitoring, earth-ionosphere and geodynamics research.The traditional IGS data download process is tedious, time-consuming and error-prone. How to obtain IGS data quickly and correctly is an urgent concern of current users. This thesis based on file transfer protocol(FTP), realtime thread pool concurrency model and broken-point continuingly transferring algorithms are designed to conduct one-stop classified acquisition test for massive IGS data. Finally, by analyzing and comparing the test result,the optimal method for massive data is obtained.

Application of spherical wavelet model in GPS elevation fitting

ZHOU Yigang, SUN Luoqing, LI Zhongzhou

2020, 0(12):  97-100.  doi:10.13474/j.cnki.11-2246.2020.0400

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The earth height and normal height of a total of 99 GPS leveling points are used to calculate the elevation anomalies, and DOG spherical wavelet model and polyhedral function are used to fit the elevation anomalies respectively. During the fitting, the points where the residual error of the model is greater than 2 times the median error are eliminated, and the fitting is performed again after the coarse error is eliminated. The accuracy of the model is evaluated by comparing the mean square deviation between the known elevation outliers of the external check points and the spherical wavelet model values and the polyhedral function fitting values. The data results show that the spherical wavelet model has a better fitting precision of 1.65 cm and the multiplanar function of 2.35 cm based on the criterion of minimum mean square error of external check.

Accuracy evaluation of MGEX broadcast ephemeris orbit and clock correction

LI Honghui, LI Jiangang

2020, 0(12):  101-105.  doi:10.13474/j.cnki.11-2246.2020.0401

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In order to evaluate the accuracy of the broadcast ephemeris provided by MGEX, the mathematical model of calculating the position of the satellite in the earth fixed coordinate system is derived, and the basic principle and method of evaluating the broadcast ephemeris by the precise ephemeris are summarized. With the help of the broadcast ephemeris products provided by MGEX system, the mean value and RMS value of orbit and clock error of GPS satellite broadcast ephemeris provided by MGEX system are compared and analyzed. The experimental results show that except the mean value of clock error is greater than 8 ns and the orbit error RMS of individual satellite is more than 4 m, the orbit precision of 7 d and 27 d broadcast ephemeris provided by MGEX is better than 3 m, and the clock error is less than 6.5 ns, which provides reference for users using MGEX broadcast ephemeris.

Analysis of some problems of surveying and mapping accuracy of ownership boundary and spatial control boundary in natural resource management

ZHANG Chengcheng, GUI Dezhu

2020, 0(12):  106-109,137.  doi:10.13474/j.cnki.11-2246.2020.0402

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As an important basis for the natural resource property rights management and the control of land and space use, the boundaries of natural resource ownership and space control are not only technology lines, but also policy lines. Before the establishment of the ministry of natural resources, the boundary surveying and mapping was managed separately. When the boundary was landed, there were problems such as space inaccurate and space cross conflict. In this paper, according to the needs of management space control boundary and ownership boundary management, some suggestions are proposed for improving the accuracy of boundary surveying and mapping and boundary mapping standard.

Design and application of satellite remote sensing emergency monitoring information service framework—a case study of forest fire in Muli, Sichuan Province

TANG Xinming, LIU Kun, WANG Jie, GAN Yuhang, LOU Linjiang

2020, 0(12):  110-113,154.  doi:10.13474/j.cnki.11-2246.2020.0403

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Establishing a timely and effective satellite remote sensing emergency monitoring information service framework is an important part of capacity for carrying out the natural disaster emergency rescue. This article focuses on key technologies such as integrated data management, multi-source data processing, disaster response information analysis, and rapid release of information services.At the same time, a satellite remote sensing emergency monitoring information service framework is constructed, relying on efficient interconnection mechanisms and high-speed data channels.Through the specific application in the emergency remote sensing monitoring of forest fires in Muli, Sichuan, the real-time delivery of disaster data before and after disasters have been realized. Besides, comprehensive information services such as remote sensing interpretation image, three-dimensional topography, rescue accessibility and fire changes in disaster areas have been timely released. This framework will provide scientific guidance for the frontline fire rescue work in Sichuan Province and technical approaches for the construction of national emergency response capacity in the new period.

Design and implementation of differential positioning equipment based on continuously operating reference station

LIU Xingwei, SHI Junbo, PU Dexiang, XU Chaoqian

2020, 0(12):  114-117.  doi:10.13474/j.cnki.11-2246.2020.0404

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Global satellite navigation positioning (GNSS) technology provides an effective means of real-time positioning for industries. Currently widely used real-time GNSS positioning technology can be divided into two types, one is low-cost positioning technology, which uses cheap chips and antennas, mainly used in mobile phones, shared bicycles and bus positioning, etc. The other is high precision GNSS positioning technology, which uses network RTK technology combined with geodesy antennas and receivers to provide real-time centimeter-level services for high-precision survey users. With the development of technologies such as the Internet of things and 5G, the requirements of real-time sub-meter and decimeter-level positioning are gradually increasing. The original low-cost GNSS positioning technology cannot meet this precision requirement, and the high-precision positioning equipment is expensive and cannot be used in the mass-market. Therefore, this paper implements a low-cost differential positioning equipment based on CORS. The equipment consists of two parts: external devices and mobile phone. Experiments show that after accessing the CORS, the positioning precision of the horizontal can reach sub-meter level with the accurate VRS observations of the CORS. This paper has certain significance for promoting the wide application of CORS.

Construction and display of integrated 3D water and underwater scenes

ZHANG Xiaoqing, HU Huihui, WANG Zhizhong, DU Yao, YANG Haibo

2020, 0(12):  118-121.  doi:10.13474/j.cnki.11-2246.2020.0405

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With the development of unmanned aerial vehicle (UAV) and new aerial photography technologies, UAV tilt photography technology has played an important role in the acquisition of large-scale terrain data, and research related to 3D mapping has been greatly promoted. However, there are relatively few studies on the integrated production process of water terrain and underwater terrain required by the water conservancy industry. This paper sets up a unified control point, uses fixed-wing UAV tilt photogrammetry to survey the terrain on the water, and uses RTK in conjunction with a depth sounder to collect three-dimensional terrain data on the river. For river-related buildings, BIM software is used for parameterization mold. Finally, fusion processing is performed on the water terrain data, the underwater river terrain data and the three-dimensional model of the building to obtain the integrated three-dimensional river scene of the water and underwater, and the Cesium platform is built for three-dimensional display. The research results can provide technical assistance for integrated mapping and visualization of water and underwater, and help promoting the evolvement of smart irrigation works applications.

A method of river networks relationship establishing for river chief system application

REN Dongyu, DONG Xianmin, ZHOU Qi, LUO Hao, YANG Jun

2020, 0(12):  122-127.  doi:10.13474/j.cnki.11-2246.2020.0406

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Spatial data is an important foundation for the work of river chief system. Establishing a reasonable river networks relationship is the core issue of geographic information technology for river chief system. Oriented to the needs of basic information management on the river chief system, the paper expounds profoundly the organizational structure and interrelationships of the river networks. Secondly, a new method of establishing river networks relationship is proposed. The relationship between the branches of the river, the hierarchical relationship of the river section, the downstream relationship on the river network and the subordinate relationship of water objects is analyzed. Finally, the structured expression, iterative construction, physical storage and representation of river networks relationship is discussed. And it briefly introduces the application of this river network relationship in the construction of the basic information platform of river chief system in Sichuan Province.

Construction of intelligent geological and mineral business support platform based on big geological data

YU Guangting, CAO Fawei, LIU Tongwen, HU Ziyuan, XU Chuanxin, XUE Liming, HE Zuchen

2020, 0(12):  128-131,163.  doi:10.13474/j.cnki.11-2246.2020.0407

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In order to explore new models of “Internet + geological work” and better serve the construction of ecological civilization, the geological and mining departments actively promote the construction of wisdom geological and mining engineering. Geological big data has been widely used in the city geology, marine geology, agricultural geology, eco-environment geology and other fields. Therefore, it is urgent to built an application support platform based on the wisdom of the large geological data mining business system, for the development of geological mining business system, the whole business online operation and regulation provides the basis of unified technology platform and operating environment, realization of business collaboration between departments and geoscientific information sharing. This paper describes the construction of the platform in details.

Construction of one-stop geographic big data intelligent platform

XU Jiayuan, WEN Xinjian, WANG Simin, PENG Huier

2020, 0(12):  132-137.  doi:10.13474/j.cnki.11-2246.2020.0408

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Based on the geographic big data system, this paper discusses the research idea of “GIS+BI”, and establishes a new geographic information data management and analysis model through the collection, storage, management, sharing, correlation analysis and visual display of geographic big data, meeting the demande of multiple applications such as national conditions monitoring, basic surveying and mapping, cadastral surveys, resource auditing. The paper builds a data ecological model based on the concept of “geographic big data warehouse” to build a “unified standard, comprehensive information, dynamic, on-demand changeable, convenient and easy-to-use” one-stop geographic big data intelligent platform with geographic big data as its core value, and realizes the visualization and dynamic intelligent analysis of geographic big data, responds quickly, and maximizes the value of data, allowing data becomes productivity.

Using Gauss projection to realize band change of AutoCAD topographic map

CHEN Zeyuan

2020, 0(12):  138-143.  doi:10.13474/j.cnki.11-2246.2020.0409

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Gauss projection band changing of topographic map is an important work in the process of surveying and construction of engineering projects. It can be realized with the help of GIS software, but it is unable to solve the problem of projectionon arbitrary elevation plane.Moreover, it is easy to lose graphic information in the transformation of AutoCAD map and GIS map. In this paper, three common ellipsoid expansion Gauss projection band conversion methods are introduced, and DXF file coordinate direct modification method and graphic entity position attribute modification method are implemented on AutoCAD platform.The test results show that the method in this paper is rigorous in theory, the result of gauss projection band change is accurate and the software has strong practicability.

Application of underground pipe network informationization in the construction of smart park

FENG Lin

2020, 0(12):  144-147.  doi:10.13474/j.cnki.11-2246.2020.0410

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Through the research and analysis on the status quo of pipeline construction informatization in smart parks (industrial parks, campuses, factories, residential quarters, etc), this paper visualizes the underground pipeline data in three dimensions aiming at the current problems of underground pipelines in the construction process of different parks (inaccurate data, unupdated etc.). The 3D visualization technology, internet of things technology, data mining technology and component development technology are applied to the construction of the intelligent management system of the underground pipe network information system in the smart park. On the basis of the Internet of Things, the layout of monitoring equipment and the integrated system of 2D and 3D, it has realized the integrated management of underground pipeline monitoring, control and management; it provides services for park long-term planning, infrastructure construction and park management, as well as technical support for pipeline planning, emergency and reconstruction.

The emerging engineering education construction for surveying and mapping specialty

YAN Li, LI Jiancheng

2020, 0(12):  148-154.  doi:10.13474/j.cnki.11-2246.2020.0411

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The construction of emerging engineering education (3E) for surveying and mapping specialty represents the innovation and reform way of the national higher education to support the powerful country in both surveying and mapping science and geographic information industry area. In the article, we analyze the evolution and development opportunities of the specialty in China, propose the idea of 3E construction guided by intelligent surveying and mapping. The paper also puts forward the ability and quality model of 3E talents in the specialty, and the 3E construction route under STEM concept.

The cultivation of mathematical literacy of students majoring in geographic information science

LI Lianying, LIU Ziwen, LIU Peilan, SHEN Yuanchun, HE Zongyi, REN Fu

2020, 0(12):  155-159.  doi:10.13474/j.cnki.11-2246.2020.0412

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Geographic information science involves geography, surveying and mapping, mathematics, computer science and other disciplines. In terms of cultivation, geographic information science emphasizes knowledge learning of geography and surveying and mapping science on the one hand, and it emphasizes quality education represented by mathematical literacy on the other hand. This paper focuses on the relationship between mathematical literacy, core elements and professional course learning, and takes the grades of students majoring in geographic information science of Wuhan University as an example to analyze the correlation between mathematical literacy and professional course learning. The results show that mathematical literacy is helpful to the study and deepening of geographic information science. The teaching of professional courses in geographic information science should stimulate students’ mathematical thinking, which is not only conducive to the improvement of students’ mathematical literacy, but also conducive to the understanding and sublimation of professional courses. At the same time, practice is the best way to test and exercise mathematical literacy, students should constantly improve their mathematical literacy and comprehensive ability in practice.

Detection and application of steel structure disturbance based on 3D laser scanning technology

SONG Yunji, WANG Xiaomin, WANG Zhi

2020, 0(12):  160-163.  doi:10.13474/j.cnki.11-2246.2020.0413

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Under the long-term load and non-uniform force, the steel structure will produce space deformation, among which the disturbance degree is an important measure index. Usually the total station instrument is used to collect some characteristic points on the steel structure axis to analyze and calculate. Because the steel structure characteristic point is difficult to capture, the measurement has the error, and the limited space discrete point is difficult to fully reflect the steel structure spatial deformation. Uses Leica RTC360 3D laser scanning to measure the disturbance of steel structure in the paper. It introduces its operation flow and data processing method. The 3D point cloud of each station is spliced into a whole by using the target, the spatial feature points and axes are extracted by the fitting method, and the spatial model is constructed by using 3D point cloud.

Integrated operation of electric power engineering surveying and mapping based on Trimble GNSS system

LI Bin, MA Chao, CHANG Zengliang, GAO Xingguo, QU Meng

2020, 0(12):  164-166.  doi:10.13474/j.cnki.11-2246.2020.0414

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Due to the particularity of electric power engineering surveying and mapping, the traditional production mode of electric power engineering surveying and mapping is separated from the internal and external work, which has repetitive labor and low efficiency. To solve this problem, this paper is based on Trimble GNSS system puts forward a new solution, develops a set of internal and external integrated operation system, solves technical problems such as data communication at different equipment ends, unified coding of ground object attributes, base map loading and sketch drawing, and can easily collect survey data and ground object attributes in the field, and automatically generate CASS, DH field operation code files and relevant reports. Through field engineering test, the system not only saves a lot of time, manpower and material resources, but also is intuitive and easy to use, not easy to make mistakes.