Table of Content

25 October 2022, Volume 0 Issue 10

Previous Issue    Next Issue

Landslide deformation monitoring based on the SBAS-InSAR technology and UAV image

XI Wenfei, ZHAO Zilong, LI Guozhu, ZHOU Dingyi, YANG Zhengrong

2022, 0(10):  1-6.  doi:10.13474/j.cnki.11-2246.2022.0286

Asbtract ( )   HTML ( )   PDF (11310KB) ( )  

References | Related Articles | Metrics

Due to the serious impact on human safety from landslide, it is of great significance for preventing landslide disasters to identify the landslide deformation accurately. Spatially continuous surface deformation monitoring can be performed using SBAS-InSAR technology, but the changes in the landslide boundary cannot be accurately obtained. In order to monitor the landslide comprehensively, the study adopts landslide deformation monitoring method combined with SBAS-InSAR technology and UAV image. A total of 80 Sentinel-1A SAR images are used from January 1 January 2018 to 24 December in 2020 for VV polarization and VH polarization data processing. The line of sight (LOS) direction deformation rate of landslide area is obtained by SBAS-InSAR technology, and several deformation points are selected for landslide deformation timing analysis. UAV is used to obtain landslide image and analyze the deformation of landslide boundary. Based on the verification of landslide cases, the experimental results show that the deformation trend of the landslide obtained by SBAS-InSAR technology and the UAV is basically consistent. The comprehensive deformation of landslide can be obtained through this method, which is of great significance for the judgment of landslide activity.

Landslide monitoring in BeiDou and displacement prediction based on GBR

MING Lulu, GAO Pinhong, LIU Yuhang, WANG Peng, TU Liping, KE Fuyang

2022, 0(10):  7-12.  doi:10.13474/j.cnki.11-2246.2022.0287

Asbtract ( )   HTML ( )   PDF (2819KB) ( )  

References | Related Articles | Metrics

The accurate prediction of landslide displacement is mainly affected by the prediction model and parameters. Traditional landslide prediction models, such as regression model and grey prediction model, have the shortcomings of single factor and low accuracy of long-term prediction. However, gradient enhanced multiple regression model can realize long-term prediction of landslide surface displacement on the basis of considering multiple factors, which can effectively make up for the above shortcomings. At last, it will be used in nanshan landslide in xining city as an example, based on the various influence factors of landslide, merit-based landslide induced key factors (precipitation, geological structure, topography). And a variety of methods are used for comparative analysis, including gradient boosting regression, Bayesian ridge, elastic net and support vector regression of four model. Experimental results show that the EV, MSE and MAE of GBR are 0.99 mm², 0.04 mm and 0.15 mm, respectively. In addition, GBR is used to predict the surface displacement in December 2020, and the relative error is found in the range from-0.8% to 0.8%. The prediction accuracy is the highest. Therefore, the gradient enhanced multiple regression prediction model is relatively more accurate and efficient. It can accurately reflect the change state of landslide surface displacement, accurately monitor and warn the landslide body all day long, and ensure the safety of the surrounding environment of the landslide body.

Landslide sensitivity assessment and error correction based on InSAR and random forest method

HUANG Long, SUN Qian, HU Jun

2022, 0(10):  13-20.  doi:10.13474/j.cnki.11-2246.2022.0288

Asbtract ( )   HTML ( )   PDF (18189KB) ( )  

References | Related Articles | Metrics

Landslides not only affect the sustainable development of the social economy but also threaten the safety of human life. A landslide sensitivity map (LSM) is considered to be one of the effective means to predict the spatial location of landslides, but the LSM generated by existing methods is affected by false negative errors, so it is difficult to obtain reliable prediction results. This paper proposes an improved LSM method based on InSAR deformation results to solve this problem. The experimental results in Zhouqu county, Gansu province show that the landslide sensitivity grade within the study area has increased by 2.74%. The comparison results between the original LSM and the improved LSM in two specific regions show that the improved method can make a more reliable landslide sensitivity map in the area affected by landslide creep.

The evaluation of ecological vulnerability of Xilingol based on EVI

LI Maolin, YAN Qingwu, LI Guie

2022, 0(10):  21-27.  doi:10.13474/j.cnki.11-2246.2022.0289

Asbtract ( )  

References | Related Articles | Metrics

Based on the composite index method, this paper constructs an ecological vulnerability model. On this basis, we study spatio-temporal evolution of ecological vulnerability in the past 20 years by means of gravity transfer and trend analysis. What is following is the discussion on the driving influence of natural and social factors on ecological vulnerability and the characteristics of spatio-temporal distribution. Our major findings include:① In terms of time, the overall ecological vulnerability of the study area improves, and the disturbance partition feature is significant. The ecological management of mining and pastoral areas has been effective, while the ecological vulnerability of agricultural areas has been degraded and needs to be controlled further. ② Spatially, the distribution of ecological vulnerability in the study area is in a stepped distribution and the center of gravity of ecological vulnerability gradually shifts to the east. The ecological vulnerability in western Xilingol has been continuously improves, and in the central and eastern regions it has been relatively stable, with degradation occurring in local areas. ③ As far as driving factors is concerned, the dominant characteristics of natural factors are significant on the spatial scale, and the dominant characteristics of social factors are gradually strengthened over time.

A remote sensing image object knowledge association method based on geographic knowledge

HUANG Zihang, JIANG Bingchuan, WANG Ziquan

2022, 0(10):  28-36.  doi:10.13474/j.cnki.11-2246.2022.0290

Asbtract ( )  

References | Related Articles | Metrics

Remote sensing image target recognition technology has been widely used in the field of target dynamic monitoring and positioning. However, the result of image target recognition lacks the link with the target attribute information, which makes it difficult for analysts to carry out more complex target data association analysis and mining. In view of the lack of semantic attribute information in remote sensing image target recognition, the target information of image discrimination is linked to the semantic web by using knowledge graph technology. Firstly, the framework of building remote sensing image target knowledge graph is proposed. Secondly, according to different data types of remote sensing image targets, a remote sensing image target knowledge extraction model is constructed. The method of object entity recognition based on similarity and relationship extraction of predefined patterns are proposed. Then, based on the image object entity linking method considering the multiple features logistic model, the knowledge association between the remote sensing image object entity and the encyclopedia knowledge base is realized. Finally, experiments are carried out in the predetermined experimental area to verify the feasibility of this method.

A lightweight dense connection network for object detection of remote sensing images

LIU Ji, YANG Jun

2022, 0(10):  37-43,55.  doi:10.13474/j.cnki.11-2246.2022.0291

Asbtract ( )  

References | Related Articles | Metrics

Two issues arising out of the small objects, detected within UAV remote sensing images, sometimes happening to be multiple and dense increases in both the misdetection and miss out rates. A lightweight target detection algorithm is proposed based on YOLO v4 with a dense connection network module to realize high precision identification of the small targets. Firstly, feature reuse and feature extraction enhancement are facilitated by adjusting the convolutional layers of CSP Darknet53 (backbone network of YOLO v4) to work in two modes of actions:dense connection and sparse connection; the gradient disappearance problem is also alleviated. Secondly, the proposed module tailors the models to fit into a reduced number of network layers; then the resulting module is redefined as the new densely connected network module. Experiments are carried out on the NWPU-VHR-10 and Vihicle-850 UAV image datasets, a courtesy of our research group. Our model has the upper hand in terms of the number of the accurately detected small targets within the remote sensing images; our implementation is also cost-effective in terms of the network model convergence time and memory consumption. A significant improvement in the speed of detection is gained.

Prediction of PM_2.5 concentration based on optimized BP neural network with improved sparrow search algorithm

ZHAO Kan, SHI Yun, NIU Minjie, WANG Huqin

2022, 0(10):  44-48,104.  doi:10.13474/j.cnki.11-2246.2022.0292

Asbtract ( )  

References | Related Articles | Metrics

Aiming at the problems of slow convergence speed and easy to fall into local extremum of traditional BP neural network model, this paper uses PWLCM(piece wise linear chaotic map)and FA(firefly algorithm)to improve SSA(sparrow search algorithm)and optimize the initial weights and thresholds of the BP neural network model to predict the PM_2.5 concentration in Xi'an. By comparing the evaluation indicators of the prediction results of different models, compared with the better-performing SSA-BP model, the RMSE, MAPE and MAE of the ISSA-BP model prediction results decrease by 3.70, 3.73 and 3.34, respectively. The experimental results show that the improved sparrow search algorithm has efficient global optimal search ability. The optimized ISSA-BP neural network has high prediction stability and accuracy, which is better than BP and SSA-BP neural network models and can be used to predict PM_2.5 concentration.

Research and ground validation based on the visual positioning methods for rover in deep space exploration

CEN Wenguang, XU Xiong, WANG Guojian, XIAO Changjiang

2022, 0(10):  49-55.  doi:10.13474/j.cnki.11-2246.2022.0293

Asbtract ( )   HTML ( )   PDF (4794KB) ( )  

References | Related Articles | Metrics

Rovers are commonly used in deep space exploration missions and it is important to develop the ability for autonomous navigation and positioning of rovers. In this paper, a typical visual simultaneous localization and mapping (SLAM) technique for navigation and positioning is studied. Firstly, the general visual-SLAM framework is summarized and the well-known ORB-SLAM3 method is introduced to evaluate its effectiveness for the deep space exploration missions. In addition to the public datasets, a simulated ground test field for extraterrestrial environment is built and the corresponding datasets are further used to validate the possible application for visual-SLAM methods in Lunar and deep space explorations. This study can help to expand the applications of the state of art SLAM methods and also support the following long-distance rover exploration tasks for China's missions.

Development of a real-time high-precision positioning system based on smartphones and vehicle-mounted application test

WANG Yixin, LIU Hui, QIAN Chuang, FAN Xiaoyun

2022, 0(10):  56-61.  doi:10.13474/j.cnki.11-2246.2022.0294

Asbtract ( )  

References | Related Articles | Metrics

With the development of smartphones with multi-system GNSS observations, the raw GNSS observations of the smartphones are feasible for high-precision positioning, which has become one of the research hotspots. In this paper, we develop a set of real-time high-precision positioning system for smartphones based on reverse RTK, which could reduce the computing pressure of smartphones. Based on Mi 8 smartphone, we perform a large-scale (Shenzhen, Wuhan and Beijing), multi-scenarios (urban open/blocking, highway open/blocking) dynamic vehicle-mounted application test to verify the reliability and usability of the system. The results show that the system can operate stably and effectively in all scenarios. Besides, we can achieve sub-meter real-time dynamic positioning accuracy under the open sky environment, with an optimal accuracy of 0.21 m.

The research status and development trend of UUVs cooperative localization technology

CHAI Hongzhou, DU Zhenqiang, Xiang Minzhi, Huang Ziru

2022, 0(10):  62-67,92.  doi:10.13474/j.cnki.11-2246.2022.0295

Asbtract ( )   HTML ( )   PDF (2275KB) ( )  

References | Related Articles | Metrics

With the growing autonomous, unmanned and intelligent of underwater equipment, it becomes an inevitable direction for unmanned underwater vehicles (UUVs) in the form of clusters. The research status of UUVs equipment and the implementation of related projects are firstly presented in this paper. Then the research progress of UUVs cooperative localization technology is systematically reviewed in configuration designing, observation error correcting, model and solution methods, and underwater acoustic communication. Besides, the development trend of UUVs cooperative localization technology is carefully analyzed, for example, the visualization of UUVs configuration design, the refinement of multi-source sensor error modeling, the intelligence of UUVs cooperative localization algorithm, and the real-time quality control of positioning results. At last, the future development of UUVs cooperative localization technology is prospected.

Assessment of the bathymetry and ability to withstand wind and waves in shallow waters for unmanned surface vessels

CAO Baojie, GAO Zhiqiang, SHANG Weitao

2022, 0(10):  68-72,79.  doi:10.13474/j.cnki.11-2246.2022.0296

Asbtract ( )  

References | Related Articles | Metrics

Traditional survey vessels can not perform bathymetry in shallow waters due to their large draft values. Unmanned surface vessels(USV) with small draft values provide new solutions for bathymetry in shallow waters. Using USV, non-tide sounding and network GNSS RTK technology, the bathymetry experiments in shallow waters are performed under different wind and waves conditions. The ability of USV to withstand wind and waves while working in shallow waters is quantitatively assessed from path tracking precision and bathymetry accuracy. The results show that wave height of 0~0.3 m and wind level of 0~2 are the reasonable threshold for bathymetry in shallow waters using USV. The USV with non-tide sounding technology can achieve high-precision measurement of bathymetry in shallow waters, and the accuracy can meet the requirements of relevant sounding specifications under reasonable wind and waves conditions. USV has broad application prospects in bathymetry and seabed topography survey in shallow waters.

Identification of highway accident black spots based on spatio-temporal density clustering

ZHANG Yunfei, ZHANG Zexu, ZHU Fangqi

2022, 0(10):  73-79.  doi:10.13474/j.cnki.11-2246.2022.0297

Asbtract ( )  

References | Related Articles | Metrics

Due to the characteristics of high driving speed and difficulties of controlling traffic flow, highway traffic accidents are often more serious than that of urban roads. Hence, it is a crucial issue in the traffic engineering field to identify the highway black spots and analyze their spatio-temporal association patterns. Traditional statistical methods may be confronted with the problem of modifiable areal unit problem(MAUP), which means the accuracy of identifying accident black spots directly depends on the basic unit size. Traffic accident is a representative spatio-temporal event, which often contains particular spatio-temporal patterns. The paper proposes a novel method to identify the highway black spots based on spatio-temporal density-based spatial clustering of applications with noise (DBSCAN) clustering. The proposed method considers the time periodicity and accident severity into calculating the spatio-temporal neighboring indicators and then finds various traffic accident black spots of multi-spatio-temporal scales based on the density-connecting rules of DBSCAN. The experimental results of 2012-2016 highway crash datasets in Hunan province illustrate the proposed method can adaptively identify the traffic black spots of different length, efficiently overcome MAUP problem, and meanwhile mine the spatio-temporal aggregative characteristics of traffic accidents to provide auxiliary decision supports for making suitable emergency plans for traffic safety.

Algorithm of regional co-location patterns based on rough set

WU Jing, FU Youjie, CHENG Penggen

2022, 0(10):  80-85,104.  doi:10.13474/j.cnki.11-2246.2022.0298

Asbtract ( )  

References | Related Articles | Metrics

Through co-location pattern mining, we can find the set of events frequently occurring in nearby locations, which provides important decision support for revealing the symbiosis law between geographical phenomena.Due to the spatial heterogeneity of co-location patterns, the existing methods can not detect the distribution of co-location patterns.Therefore, in this paper, we detect the distribution regions of isotopic patterns from the direction of proximity of geographical attributes, and propose a local co-location pattern mining method based on rough sets.Firstly, infrequent co-location patterns are extracted from the global perspective as candidate local co-location patterns. Then, the locations of the candidate co-location patterns are processed, and the attributes of hot spots are used as rough data sets to detect the natural distribution regions of local co-location patterns. Finally, the frequency of these local regions is measured and all frequent local co-location patterns are generated. Through experiments and applications, it is found that this method can not only detect the similarity region of local spatial distribution of the same location pattern, but also reflect the geographical attribute information of the same location pattern distribution region.

Influence of oblique photography equipment selection and image control point layout on high-precision 3D real scene model reconstruction

XI Siyuan, ZHANG Xitong, WANG Ning, ZHANG Zhaojiang, LI Jianming, ZHANG Guodong

2022, 0(10):  86-92.  doi:10.13474/j.cnki.11-2246.2022.0299

Asbtract ( )  

References | Related Articles | Metrics

In the production of high-precision 3D real scene models, the selection of UAV platforms and loads and the laying of image control points are of great importance, which affect the efficiency of aerial photography, model accuracy, and model effects. In this paper, an urban village in north of China is used as a research area, and different UAV oblique photogrammetric equipments are used to obtain oblique images of the same resolution respectively, and combined with different image control point laying schemes to reconstruct the 3D model of the real scene. Through different equipment and image control point laying combinations, and original images of the same resolution, a test group is formed to compare and analyze flight efficiency, model accuracy and model effect. Thus, equipment selection and economical and reasonable image control point layout for meeting high-precision 3D real scene model reconstruction requirements are studied so as to provide guidance for actual production operations.

Large scale topographic map updating method based on tilt model and LiDAR point cloud in urban complex terrain environment

YAN Xiaohong, RONG Yanxiang, SUN Kexin, LI Xumin

2022, 0(10):  93-99.  doi:10.13474/j.cnki.11-2246.2022.0300

Asbtract ( )  

References | Related Articles | Metrics

UAV tilt photography technology is greatly affected by occlusion and is difficult to penetrate the densely vegetated area, this paper proposes a method to update the large-scale digital topographic map of a small area with the tilt model combined with LiDAR point cloud in the urban complex terrain environment. Firstly, the UAV of five lens and six rotor is used to take two full-scale photos of the experimental area in the direction of vertical and parallel to the main buildings, and the unmanned airborne laser radar collects the point cloud in the whole area, and carries out a single lens low altitude make-up flight for the villa area less than 10 m. After aerial triangulation, the inclined image point cloud and airborne laser point cloud are fused for modeling. Comparing three modeling schemes, the inclined 3D model of the fusion modeling is the best in position accuracy and model quality. Finally, the mapping is carried out based on this model. The accuracy evaluation shows that under the condition of reasonable flight scheme and image control point layout in the urban complex terrain environment, the plane and elevation accuracy of the 1:1000 digital topographic map collected by the inclined three-dimensional model fully meets and is better than the accuracy index of the dynamic update of the 1:1000 digital topographic map in Shenzhen.

Multi-beam point cloud denoising and the application for 3D registration of water flow

WANG Min, LIU Chuang, WANG Bin

2022, 0(10):  100-104.  doi:10.13474/j.cnki.11-2246.2022.0301

Asbtract ( )  

References | Related Articles | Metrics

Aiming at the problem that it is difficult to retain fine features and accurately "lock" riverbed morphology in multi-beam point cloud denoising, a multi-beam point cloud denoising algorithm is proposed for 3D registration of water flow of natural resources. On the basis of KD tree search, statistical filtering theory is introduced to classify multi-scale noise and eliminate large scale noise. Based on the principle of minimum information entropy, the optimal neighborhood is determined based on the principal component analysis (PCA) algorithm, and the curvature information entropy is constructed to optimize and improve the bilateral filtering factors, so as to achieve the purpose of denoising and preserving fine features of underwater terrain point cloud. Experiments show that the proposed algorithm is feasible, can effectively ensure the fine features of underwater terrain and applied to the 3D registration of water flow of natural resources.

A StaMPS PSI time series analysis method combined with GACOS and linear atmospheric correction

HE Xishan, ZHOU Ping, CHEN Gang

2022, 0(10):  105-109,128.  doi:10.13474/j.cnki.11-2246.2022.0302

Asbtract ( )  

References | Related Articles | Metrics

The radar signal will get propagation path delay when it through the atmosphere, which will affect the accuracy of InSAR measurement. Although the conventional time series InSAR analysis method based on spatio-temporal filtering can weaken its influence, it still has certain limitations. StaMPS PSI time series analysis method is favored by many scholars because of its many advantages.Therefore, in this paper, taking Hong Kong as an example,a StaMPS PSI time series analysis method combining GACOS and linear atmospheric correction is proposed and compared with conventional StaMPS PSI. Finally, GNSS observation data is used to verify the InSAR results. The results show that the conventional time series analysis method can better overcome the influence of atmospheric delay when the SAR data sets are abundant, but the new method can better reflect the real surface deformation.

Monitoring and analysis of dynamic deformation of offshore platform using GNSS PPP

XIONG Zhinan, YE Zuoan, CHEN Shi, YU Lina

2022, 0(10):  110-113.  doi:10.13474/j.cnki.11-2246.2022.0303

Asbtract ( )  

References | Related Articles | Metrics

It is of great significance to monitor the dynamic deformation of offshore platforms under environmental excitation in real time to ensure their safe operation. GNSS PPP technology can achieve precise single-point positioning only by relying on single-point monitoring stations, which does not need to set up base station, thus GNSS PPP has potential application value in the field of marine platform deformation monitoring. Aiming at the problem of low accuracy of GNSS PPP monitoring signal interfered by background noise, the improved CEEMDAN algorithm is proposed to filter and denoise the monitoring signa and applied to the dynamic deformation monitoring of an offshore platform. The results show that:① The GNSS PPP technology combined with the improved CEEMDAN can effectively monitor the dynamic deformation of the offshore platform structure. ② The improved CEEMDAN can effectively eliminate the interference of background noise of GNSS PPP. ③ The clear 3D displacement trajectory of the monitoring point can be obtained based on the denoised signal, which can provide references for structural safety assessment.

Height conversion method and result analysis based on polynomial surface fitting model

CHEN Anping, LI Hongwei, XIE Gangsheng, YAO Chaolong, XIE Huirong

2022, 0(10):  114-117,157.  doi:10.13474/j.cnki.11-2246.2022.0304

Asbtract ( )  

References | Related Articles | Metrics

Considering the impacts of selection of fitting models and fitting points on the precision of height conversion based on polynomial surface fitting, this study proposed GNSS height fitting methods by integrating different polynomial curved surface models based on the analysis of their features and the information about fitting residuals of fist order polynomial. The effectiveness of the proposed model was evaluated by a case study. The results show that the spatial distribution of fitting residuals of fist order polynomial, which reflects the feature of regional height anomalies, can provide a basis for dividing sub-regions for quadratic polynomial fitting or the selection of fitting points for cubic polynomial, and the fitting precision can be increased from centimeter level to millimeter level.

Detection of underwater block stone in Qiantang River revetment engineering based on unmanned ship measurement system

BI Jixin, LIU Qiang, WU Wenchao, ZHAN Xiaoming

2022, 0(10):  118-123.  doi:10.13474/j.cnki.11-2246.2022.0305

Asbtract ( )  

References | Related Articles | Metrics

As the key link of Qiantang River seawall revetment engineering, the detection and identification of underwater block stone is very important to ensure the construction efficiency of sheet piles. Based on the research on the core technology of shore-based communication and data acquisition of the unmanned ship measurement system, the NORBIT multi-beam sonar resolution estimation model and the maximum beam opening angle, the minimum data update rate and the maximum speed of the additional rock particle size constraints are derived. The relationship and recommended value of,combined with the three-dimensional characteristics of the Qiantang River underwater multi-beam scanning point cloud data, the region growing algorithm is improved to realize the identification and extraction of the boulder point cloud. The engineering practice results show that the optimized multi-beam sonar parameters of the unmanned ship measurement system can achieve accurate detection of small underwater rocks, and can faithfully reflect the real situation of underwater block stone and surrounding micro-topography. The point cloud of underwater block stone is extracted from the point cloud data of many riverbeds to provide accurate distribution of boulders for sheet pile construction, which has good engineering application significance.

Analysis of geographic entity classification method and database construction for city services

WANG Huajuan

2022, 0(10):  124-128.  doi:10.13474/j.cnki.11-2246.2022.0306

Asbtract ( )  

References | Related Articles | Metrics

Geographic entity data is a real 3D structured and semantic product, and it is the standardized product data of real 3D construction. Based on the analysis of the technical guidance documents of the Ministry of Natural Resources and the relevant research and application of the construction of geographical entities in the pilot cities, and based on the practical experience of building the database of entities in the pilot areas of Zhuhai city, this paper proposes a classification method of geographical entities oriented to city level services, and constructs a geographic entity data set oriented to application services. Taking courtyards, buildings, road entities, etc. as examples, the data organization structure is analyzed in depth, and application research oriented to land spatial planning and urban fine governance is explored.

A method of mobile phone user positioning based on geographic information

HE Feng, WANG Meihong, HOU Xiaoyu, ZHOU Junrong

2022, 0(10):  129-132,147.  doi:10.13474/j.cnki.11-2246.2022.0307

Asbtract ( )  

References | Related Articles | Metrics

User trajectory behavior analysis based on mobile phone signaling data has been widely used in many business fields such as traffic monitoring, urban management, and population analysis. Aiming at the shortcomings of mobile phone base station positioning deviation and lack of semantic information, this paper proposes a positioning method based on geographic information. Firstly,we construct the specification of geographic entity data, then establish the weight mapping relationship between geographic entities and base stations by clustering the mobile phone signaling data, and fit the user trajectory to the actual geographic entity using spatio-temporal reasoning and deep learning technology, and finally realize the method.The verification results show that this method improves the accuracy of user positioning and provides reliable data support for the application of subsequent business scenarios.

The problems and resolutions in filing specialized archives in new era: taking the archives of surveying,mapping and geoinformation for example

WANG Xiaoping, ZHAO Yong, LI Jia, ZHU Jie, BAI Ju

2022, 0(10):  133-137.  doi:10.13474/j.cnki.11-2246.2022.0308

Asbtract ( )  

References | Related Articles | Metrics

This paper summaries the current development situation of the regulations and technologies of filing specialized archives. And taking the archives of surveying, mapping and geoinformation for example, this paper points out the problems existing in filing the specialized archives, and puts forward the solutions to strengthening specialized archives filing, so as to achieve the goal of filing specialized archives completely, systematically and normatively. This paper also looks into the future of specialized archives filing in the end, and recommends some technological ways for strengthening the filing.

Multi-dimensional space-time management of remote sensing image archives

LI Ming, WANG Chenzhe, WANG Xiaoping, SONG Hongyun, BI Kai, BAI Ju

2022, 0(10):  138-142.  doi:10.13474/j.cnki.11-2246.2022.0309

Asbtract ( )  

References | Related Articles | Metrics

As an important basic geographic information, remote sensing image archives can provide key decision-making basis for natural resources supervision and monitoring, urban sustainable development planning, etc. In view of the current situation of remote sensing image archives with multi-source, multi-media, multi-scale and multi-specification, this paper analyzes the key problems existing in the current remote sensing image management mode, puts forward and constructs a space-time multi-dimensional management system of "space+time+form+attribute", and realizes the scientific and efficient management and utilization of remote sensing image archives.

Key technology of filing and management of surveying and mapping archives

WANG Haiqing, LIU Yue, LI Tao, HU Bo, WU Wei

2022, 0(10):  143-147.  doi:10.13474/j.cnki.11-2246.2022.0310

Asbtract ( )  

References | Related Articles | Metrics

Since the 12th Five-Year plan, a number of major surveying and mapping projects have been implemented, national-level geomatic data has been updated annually, the output has increased sharply, and all of them is digital. The traditional archives management technology is difficult to meet the needs of the new era. Therefore, this paper analyzes the bottleneck problem, studies the key technologies of filing, storage management and retrieval of large data volume surveying and mapping archives, which have been applied to the archiving of major surveying and mapping projects and the management of national-level archives, and achieve remarkable benefits.

Technology research and implementation on upgrading and migrating the database of the national surveying and mapping archives catalogues

SONG Hongyun, WANG Haiqing, WANG Chenzhe, LI Tao, LIU Yue

2022, 0(10):  148-151,161.  doi:10.13474/j.cnki.11-2246.2022.0311

Asbtract ( )  

References | Related Articles | Metrics

Regarding the problems of various kinds of the catalogue database of national surveying and mapping archives and which lack of the regularity and which have no spatial positional index for traditional reason, in order to improve the management and service efficiency of surveying and mapping archives,through analyzing the characters of the data,choosing test data, normalization processing data, conforming spatial positional index data;using progressive upgrading technical proposal, the work of upgrading and migrating the database of the national surveying and mapping archives catalogues has been realized frequently in the meantime of development of management system of survey and mapping archives, avoid of the bad influence which is the system had been built but the catalogue database had not finished migrating and reforming.

Construction and practice of ideological and political case database in surveying and mapping geographic information course

KONG Weihua, XU Xiaoyu, ZHU Jun, HUANG Weiduo, ZHAO Hong

2022, 0(10):  152-157.  doi:10.13474/j.cnki.11-2246.2022.0312

Asbtract ( )  

References | Related Articles | Metrics

In order to solve the current situation of the lack of material mining ability and ideological and political education resources of relevant professional teachers in the course ideological and political teaching practice, after extensive research, discussion, material collection and system development, a surveying and mapping geographic information course ideological and political case database has been established. The case database is based on the ideological and political matrix map of surveying and mapping geographic information courses, and the tree structure diagram of ideological and political cases-course knowledge modules, and integrates and optimizes course knowledge modules. A multimodal curriculum ideological and political case database has been established. Using the B/S structure, the course ideological and political case database management system is established with SQL Server as the database, which realizes five functional modules including case input, case review, case query, user feedback and system maintenance. Through the application of relevant courses, it has played a great role in promoting the ideological and political realization of professional courses, and provides a strong guarantee for the cultivation of surveying and mapping geographic information talents with national self-confidence, a high sense of social responsibility and good professional core literacy.

Teaching reform of photogrammetry experiment under virtual simulation platform

BIAN Yuxia, WANG Meizhen, LIU Jinbao, ZENG Chenxi

2022, 0(10):  158-161.  doi:10.13474/j.cnki.11-2246.2022.0313

Asbtract ( )  

References | Related Articles | Metrics

With the development of UAV equipment, the application field of UAV aerial survey is constantly expanding. This situation has increased the requirements of the surveying and mapping industry for the practical operation of photogrammetry courses. However, due to the influence of aviation control, site restrictions, and weather conditions, it is difficult for some universities to implement practical teaching of UAV photogrammetry.In order to find an experimental teaching model for photogrammetry courses, the work introduces the virtual simulation UAV aerial survey teaching system, discusses the experimental teaching content of virtual and reality photogrammetry, and constructs an experimental teaching program that combines aerial photography and photogrammetry. This article aims to improve students' practical skills, breaks through the limitations of time and space and provides corresponding reform measures for the experimental teaching of photogrammetry in the post-epidemic era.

Risk source identification in metro protection area based on convolutional neural network

MIN Xing, HUANG Pinwen, TAN Jinxiang

2022, 0(10):  162-165,170.  doi:10.13474/j.cnki.11-2246.2022.0314

Asbtract ( )  

References | Related Articles | Metrics

The identification of risk sources along urban rail transit is an important method to prevent safety accidents caused by illegal operations. In order to solve the problems of low efficiency, high miss rate and high cost of traditional identification methods, this paper takes the UAV metro protection area inspection system as a platform, and uses convolutional neural network to identify the risk source of the image data collected by UAV. Firstly, the process of UAV image acquisition is introduced, and based on the original image data, multi-angle and multi-scale of risk source datasets are produced through data enhancement. Then, a method of convolutional neural network is used to establish risk source identification models to automatically identify and locate the risk source in the images collected by the UAV. Experiments show that the establishment of multi-angle and multi-scale risk source data sets further improves the recognition accuracy of the model, and this method has the advantages of high efficiency and low cost compared with traditional methods.

Acquisition and application of building entity for modernization of governance capability

CHENG Mingyu, WU Yousi

2022, 0(10):  166-170.  doi:10.13474/j.cnki.11-2246.2022.0315

Asbtract ( )  

References | Related Articles | Metrics

The city is a complex and open giant system with the governance problems of unclear chassis and low coordination in investigation, so it is in urgent need of a scientific, accurate and real-time management means. Facing the requirements of governance modernization, this paper studies a non-contact centimeter high-precision and fast urban tilt model acquisition method to improve the chassis inspection efficiency. At the same time, through structured and simplified aggregation, the corresponding logical relationship among elements, building entities and building units are established, and the basic and management attributes are obtained to build a comprehensive management platform for full cycle tracking. The practical application shows that this study provides an effective reference for realizing the fine management of urban construction information.