Table of Content

25 October 2017, Volume 0 Issue 10

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A Kind of Gauss Projection Based on the Equidistant Sphere

CHEN Cheng, JIN Lixin, LI Houpu, LIU Qiang

2017, 0(10):  1-6.  doi:10.13474/j.cnki.11-2246.2017.0306

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A kind of Gauss projection based on the equidistant sphere is studied by reason of the problem of the impracticality of calculation by using the spherical coordinates for the traditional Gauss projection based on the horizontal elliptic cylinder. First, the direct and inverse solutions of the Gauss projection based on the equidistant sphere are derived by using the direct and inverse solutions of the rectifying latitude with respect to the geodetic latitude, which help to calculate the distortions of meridians and parallels. Then, the length distortion, angular distortion, area distortion, and convergence of meridians of the Gauss projection based on the equidistant sphere are analyzed. Finally, in comparison with the traditional Gauss projection as regards these distortion parameters, the Gauss projection based on the equidistant sphere is available in practice.

Real Time and Fast Algorithm for Integer Ambiguity of Reference Stations in Large-scale Network RTK

WANG Jianmin, LI Yabo, MA Tianming, ZHU Huizhong

2017, 0(10):  7-11.  doi:10.13474/j.cnki.11-2246.2017.0307

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Network RTK,at present,is one of the important means to realize high precision and real-time dynamic positioning,while the key problem of high precision positioning of network RTK is the real-time, fast and accurate fix of the integer ambiguity between reference stations.For a wide scale network RTK, because the distance between reference stations has increased and the ionospheric delay error、the troposphere delay error and satellite orbit error have a low correlation that leads to integer ambiguity in the reference stations can not solve quickly and accurately,therefore this paper presents a method that integer ambiguity algorithm in a wide scale network RTK reference stations.Firstly,this algorithm takes advantage of L1、L2 carrier phase observations and P1、P2 pseudorange observations to calculate the double difference wide lane ambiguity between reference stations,and then to solve double difference troposphere delay by combining Saastamoinen model with Chao mapping function model,at the same time,the thesis takes the double difference wide lane ambiguity regard as constraint condition of L1、L2 double difference the carrier phase integer ambiguity so as to make sure L1、L2 double difference carrier phase integer ambiguity.The experiment was carried out by using the measured data of CORS,at the same time,the experimental results of this paper are compared with the results of GAMIT software show that the algorithm can achieve single epoch double difference carrier phase fixed integer ambiguity stably and accurately.

Comparison on Mobile Gravity among Different Spatial Interpolation Methods

ZHU Yu, WANG Wei, ZHANG Chuanyin, WANG Qingliang

2017, 0(10):  12-17.  doi:10.13474/j.cnki.11-2246.2017.0308

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The mobile gravity is an important indicator for seismic monitoring,which is essential to obtain the spatial distribution characteristics and makes up for the lack of data obtained by spatial interpolation.In this paper,we used three kinds of interpolation methods which included spherical Kriging,inverse square distance and improved Shepard to interpolate mobile gravity,meanwhile,the results were analyzed from data distribution,the number of interpolation points,interpolation resolution and search radius(search points) and verified.The results showed several meaningful conclusions,which mainly contained three aspects as follows.①Compared with spherical Kriging,inverse square distance and improved Shepard achieved better results for the interpolation of mobile gravity,nevertheless,Kriging produced well-continuity and high-smoothness results when there is less outliers and less difference in sample.②The selecting of an appropriate resolution need to according the distribution of sample points and interpolation range in mobile gravity interpolation process.③It is overwhelmingly significant to comprehensively consider the geophysical tectonic characteristics and spatial correlation and variability in the earth element interpolation.

The Effect of Colored Noise on the Three Dimensional Velocity Estimations of GPS Stations in East Antarctica Region

SONG Aihu, MA Chao, ZHOU Ning

2017, 0(10):  18-21.  doi:10.13474/j.cnki.11-2246.2017.0309

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In recent years, it has been found that there were both white noise and colored noise in the coordinate time series of GPS stations. In order to study the effect of colored noise on the three dimensional velocity estimations in East Antarctica region, the measured data of 6 GPS stations from 2005 to 2014 were used for solution and adjustment by GAMIT/GLOBK10.5 software, and the maximum likelihood method (MLE) was used to estimate the three dimensional velocities and errors of the GPS stations when two noise models were assumed. The results show that when two kinds of colored noise (flicker noise and random walk noise were considered), the 3D velocity estimations of GPS stations in East Antarctica region have small changes, the maximum impact magnitude is 0.3 mm/a in horizontal and 0.8 mm/a in vertical. However if the colored noise was not considered, the parameter estimations of the true uncertainty would be seriously underestimated.

Research on Wetland Sub-classification from GlobeLand30

CHEN Wei, CHEN Lijun, CHEN Jun, CHEN Hao, ZHOU Xiaoguang, XIE Bo

2017, 0(10):  22-28.  doi:10.13474/j.cnki.11-2246.2017.0310

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Wetland data of the Globaland30 have been classified into 8 subclasses by the improved method, which could meet the application requirements of high resolution and detailed global wetland data. This paper proposed the research framework of wetland classification, formulated the classification method, and analyzed the 8 subclasses at a global scale. The framework was composed of the definition of wetland subclass, the hierarchical classification of multiple knowledge and methods of sub date extraction. The data have been classified by the object filtering of prior knowledge, the parity pixel extraction of forest data and mask method of the maximum likelihood algorithm. The method overcomed the shortcomings of the conventional methods, such as long cycle and low efficiency, and realized the fast and accurate mapping of the global high resolution wetland subclass data,the accuracy for general wetland subclass is 82.6%. This research would be useful for monitoring and studying the land cover information in the further.

Spatial Difference Discrimination Technology of Composite Elements in Landuse Update Survey

WU Han, ZENG Jue, XU Shiwu

2017, 0(10):  29-33,38.  doi:10.13474/j.cnki.11-2246.2017.0311

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The precision requirement of landuse updating survey has been greatly enhanced,the scale of survey was also raised to 1:2000 now,it also reinforces the mechanism of checking and updating data,and the process has a specific stringent requirements.This paper studies the technology of spatial matching and discriminant analysis of complex elements in land renewal investigation,a multi-scale vector space data matching method based on buffer expansion is proposed.On the one hand,spatial features inherit the high precision of large-scale topographic cadastral data,the use of attribute feature integration multi-scale and the ownership of current information,to achieve effective integration between the same objects on the scale.On the other hand,comparison of computer differences between variable map spot issued by the state and current map spot in updated land use investigation,ensure that the update process is strict,standardized and highly automated.

An Improved Method for Water Information Extraction Using MSAM

ZHANG Wei, ZHAO Lijun, ZHENG Ke, TANG Ping

2017, 0(10):  34-38.  doi:10.13474/j.cnki.11-2246.2017.0312

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Quickly and accurately obtaining water information from satellite remote sensing imagery has become an important technical means in the field of water resources investigation and monitoring,wetland protection,and flood disaster assessment. In this paper,a new water extraction method of a modified spectral angle mapping (MSAM) is proposed and GF-4's PMS images are used as research data.Two typical study areas are investigated, which are selected from the areas of middle-east of Inner Mongolia and middle-lower reaches of the Yangtze River.To evaluate the efficacy of the proposed MSAM method,four compared methods including single band threshold,NDWI threshold, support vector machine (SVM) and spectral angle mapping (SAM) are used in water extraction.Then accuracy assessments are taken on the water extraction results of the five different methods.The results show that the proposed method can not only extract water information accurately,but also distinguish water and the cloud shadows well and have a good ability in extracting small water bodies.And it obtains the highest accuracy compared with the other four water extraction methods,with the water extracting accuracies of the two study areas reaching 99.86% and 98.37% respectively.To sum up,the proposed method can be effectively used to extract water information of GF-4 remote sensing imagery.

Point Cloud Registration Method Based on 2D Image Feature

ZHAO Fuqun, ZHOU Mingquan

2017, 0(10):  39-42,73.  doi:10.13474/j.cnki.11-2246.2017.0313

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A point cloud registration method is proposed in the paper in order to improve the registration accuracy and convergence rate of low overlapping point clouds.Firstly,a point cloud registration algorithm based on region level is used to complete coarse registration;Secondly,3D point cloud is converted into 2D image,SURF(speeded up robust features)algorithm is used to extract 2D image features,and the matching pixel pairs are solved;Finally,3D corresponding points are gotten according to the 2D matching pixels,and the rigid transformation is solved,then the fast and accurate registration of point cloud are achieved.The experimental results showed that the registration accuracy and convergence rate of proposed point cloud registration method improved about 20% and 60% respectively compared with iterative closest point(ICP)algorithm,it is a high accurate and fast point cloud registration method.

Dynamic Monitoring Method for Mining Area Based on UAV Images

ZHANG Mengxia, ZHENG Xinqi, LIU Bo

2017, 0(10):  43-47.  doi:10.13474/j.cnki.11-2246.2017.0314

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Due to the unreasonable development and utilization of the mining area, the mining area environmental problems are particularly prominent. And the dynamic monitoring of the mining area can effectively reduce the negative impact of mining activities.Traditional mine environmental monitoring adopts field inspection and step-by-step reporting, which requires not only a great deal of manpower, material and time, but also a timely response to problems, so it is necessary to find a way to meet the current mine monitoring required method. In this paper, the unmanned aerial vehicle (UAV) is used to acquire the high spatial resolution image of a mining area for dynamic monitoring of mining area. The images are processed by structure from Motion of Agisoft PhotoScan Pro software, which realize the fast mosaic of images and the rapid generation of digital elevation model and digital orthophoto map. Finally, we use ArcGIS software GIS method to obtain the DEM elevation changes in different periods and the amount of fill and excavation, to achieve dynamic monitoring of mining area. The results of the study are objective,which can provide effective data for the relevant departments of the mining area to manage and plan the exploitation status of the mining area.

Research on RGB-D SLAM Based on Image Feature

XU Xiaodong, CHEN Guoliang, LI Xiaoyuan, ZHOU Wenzhen, DU Shanshan

2017, 0(10):  48-51.  doi:10.13474/j.cnki.11-2246.2017.0315

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Aiming at the requirement of autonomous operation of the mobile robot in complex environment,this paper proposes a RGB-D SLAM based on image feature.Compared with the traditional filter method,the error accumulation during the long time motion of the robot is accumulated,adopt SLAM method based on graph optimization.Proposed algorithm is divided into two parts:frontend and backend.The frontend is responsible for processing the image data and extracting the geometric relationship between the poses of the robot,firstly,the feature points of color RGB image are extracted,high dimensional feature descriptor are created and the location correspondence of feature points is established.The backend is responsible for expressing the position and pose of the robot at each moment and diminishing the drift of the trajectory,constructing a graph of the geometric position relationship and its uncertainty,through the optimization of the graph to get the best trajectory,finally,the sparse point cloud map and trajectory are generated.The experimental results show that the proposed method is practical and robust.

UAV Image Detecting of Single Building's Angular Points Method Based on SVM

LI Lingzhi, LI Baishou, SHEN Yuzhen, XU Rui

2017, 0(10):  52-57,78.  doi:10.13474/j.cnki.11-2246.2017.0502

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In view of the present situation of single building's angular points detection in UAV images, this paper proposes a method that based on support vector machine (SVM) to detect the corner of the building.Firstly,the UAV image with four bands to complete multi-scale segmentation,calculates the NDVI of this image,to eliminate the effect of vegetation by the spectral differences between vegetation and non-vegetation areas;Secondly, using object-oriented classification to extract "building block" from the image,and the edge detection for the "building block" completed by Harris,then it comes into being edge point set of building and extracts some points as samples randomly. The edge sample points are mapped to high-dimensional feature spaces by Gauss RBF and construct the feature vector,the SVM classification model is trained by edge point set.Finally,the correct building corner is detected by the SVM classification model from the rough edge points, and the corner of the single building is extracted.

LiDAR Point Cloud Thinning Algorithm for Road Survey and Design

FANG Chengxi, SUI Lichun, ZHU Haixiong

2017, 0(10):  58-61,88.  doi:10.13474/j.cnki.11-2246.2017.0316

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When the traditional thinning algorithm is applied to data extraction of road point cloud, there are many defects, such as cannot take good account of terrain features, or appear the large area point cloud hole. In this paper, an improved algorithm based on mean curvature is proposed for the extraction of point cloud data in road survey and design. Firstly, the mean curvature of all points is obtained by local quadratic surface fitting. And then according to the mean curvature to determine the terrain features, and as the main criteria for the identification of point cloud data dilution. Finally, the problem of the large area point cloud hole in the flat road surface is solved by using the marking method. Through the experimental results and analysis, the reliability and applicability of the thinning algorithm are proved.

Automatic Processing Method for Different Borderline Symbols Intersecting on the Solid Part

YOU Xixia, LI Chengming, WU Pengda, YIN Yong

2017, 0(10):  62-67.  doi:10.13474/j.cnki.11-2246.2017.0317

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According to the Specifications for Cartographic Symbols, different borderline symbols should intersect on the solid part. However, most of graphics software doesn't consider the problem and few research articles are devoted to finding a complete solution. Based on the principle of cell cycle configuration method to design symbol, this paper provides a new algorithm to realize the intersecting of solid parts in the dashed line and designs an automatic processing method. First, the original cell block is split into two parts. Then, the original data layer is broken up into three new layers. Finally, match the new cell block with the new data layer. Practical data are used to validate the method. The results show that our method is highly reasonable and efficient. This paper provides an automatic processing method to improve the efficiency of map editing which takes into account of different grades and different types of borderlines.

A Heuristic Algorithm for Automatic Classification of River System with Ring

HAO Zhiwei, LI Chengming, YIN Yong, WU Pengda, WU Wei

2017, 0(10):  68-73.  doi:10.13474/j.cnki.11-2246.2017.0318

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The river classification is the key point and the technical difficulty for river expression in the map generalization, and the accuracy and calculation speed are higher requirements. In the previous research on river system classification, the algorithm's efficiency is low, and ring is without consideration in river system. Based on this, we set up the attribute rules, geometric rules and ring rules of river system classification to process different types of ring and use heuristic algorithm to realize the automatic classification of rivers system. The test results show that the river system containing rings can achieve good effect by this algorithm, and reduce the computation time.

The Fast Display Method for 3DCM Based on the Viewpoint Moving in Cluster Environment

LI Chaokui, FANG Jun, FANG Wen, BU Pu

2017, 0(10):  74-78.  doi:10.13474/j.cnki.11-2246.2017.0319

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With the rapid development of digital city construction, as the core content of digital city,3DCM has the characteristics of large amount of data, slow running speed, great calculation pressure and so on in the existing computer's running environment.To solve these problems, combined with the parallel computing, a new fast display method for 3DCM based on the viewpoint move rules is proposed.Using static LOD simplification algorithm to simplify the 3DCM to four resolution level.Based on the viewpoint move rules, the LOD model was selected and gradual loading according to the distance and the eccentricity ratio.The results were parallel displaying in the cluster system, which effectively solves the problems of slow load display and scene jumping for large-scale 3DCM,achieved the fast display of large scale 3DCM.Experimental results show that this method can quickly and effectively deal with large-scale 3DCM rendering, while taking into account the efficiency and showing the details of the model, has a good visual effect, which has important significance for the development of digital city.

Method of City Complex Function Area Division Based on Apportion of Shared Construction Area

ZHAO Haiyun, ZHANG Xinyuan, WU Bin, YU Zhe

2017, 0(10):  79-83.  doi:10.13474/j.cnki.11-2246.2017.0320

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Division of functional area directly affects the results of the allocation which results in the authenticity and reliability of the real estate area. Construction space or the striction, service function, and using objecte of the synthesis increases the complexity of the functional area division. This study puts forth a devision method that puts functional area around and then adds usage by analysing cases of city complex.

Method of Map Zooming and Clipping Used by Neighborhood Relationship of Geographical Multi-factor Voronoi Diagram

LI Jia, DUAN Ping, LIANG Ming, LÜ Haiyang

2017, 0(10):  84-88.  doi:10.13474/j.cnki.11-2246.2017.0321

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Aimed at the problem of information imbalance caused by the amplification of the electronic map with the Euclidean distance as the amplification factor, a method of map zooming and clipping based on multi-factor Voronoi diagram has been proposed in this paper. This method can effectively avoid the problem of the map information imbalance, which is based on the Euclidean distance as the map magnification factor. The geographical elements are abstracted as points, lines, polygons and divided into two categories:point elements and non-point elements. For point elements, construct the Voronoi diagram of point elements. For the non-point elements, namely, line and polygon elements, constructing their approximate Voronoi diagram. When the user amplify the geographical elements of the target which is interested in, only need to extract the multi-factor of the target Voronoi diagram adjacent elements. And then calculate their minimum bounding rectangle (MBR). The MBR area is used in the map clipping region, and it can keep the surrounding geographical information of the users who interest in the geographical elements of the target. The method is adopted of this paper to test some regional electronic map. The result shows that The natural neighbor method based on the multi-factor Voronoi diagram can better take into account the target and its surrounding information when amplify the map. This method can improve the legibility of the map, to avoid the Euclidean distance as the map zoom factor and multiple operations.

A Reversible Decryption Model for Vector and Raster Integration Based on Trigonometric Function

YU Hui, ZHOU Wei, MA Xinnian

2017, 0(10):  89-94.  doi:10.13474/j.cnki.11-2246.2017.0322

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Vector-raster geographic data are important part of basic geographic information data, hence the research on its security is very important. These data are open for share and use only when decrypted in terms of our country's relevant laws and regulations on decrypted geometric precision of public maps. Based on analysis of properties of description by trigonometric function, this paper devised a reversible description model for integrated vector-raster geographic data by trigonometric function with considering of the characteristics of stack use of these data. Experiments show that the model maintains well the topological relations of geographical entities with fast processing speed, high security, controlled error and good data connections.

The Characteristics Analysis of Land-use in Spatial Pattern Change of Shengjin Lake Nature Reserve in Recent Years

ZHAO Leyang

2017, 0(10):  95-99.  doi:10.13474/j.cnki.11-2246.2017.0323

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According to the image of Landsat TM in 1995,2000,2004,2009 and 2013,this paper uses supervised classification (parallelepiped,maximum likelihood,minimum distance,Mahalanobis distance) to interpret it, and makes use of high-resolution image evaluate different interpretation methods, then determines the best method of interpretation. Using the optimal interpretation method obtained the map of land-use and land-cover change in Shengjin Lake reserve by means of 5 times image. And on this basis,use of ArcGIS landscape pattern analysis tool,by analyzing the water area,the number of polygons,fragmentation and other factors,obtain land-use and landscape pattern changes in different periods. Land-use change combined the result of natural factors and human factors,researching the spatial pattern of land-use change analysis for the past 20 years,can provide us the basis for sustainable development of the regional land use and development of resources.

Indoor Positioning Navigation Based on Single Camera and Neural Network Estimation

ZHANG Lina, PENG Li

2017, 0(10):  100-105.  doi:10.13474/j.cnki.11-2246.2017.0324

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Estimating the user's location with a camera requires the establishment of a complex mathematical model because the relationship between 3D scene and a 2D image is non-linear and highly complex. In order to solve this problem,a single camera based on neural network is proposed.The main advantage of the indoor positioning system is that LED can use the visible light communication to send its location information.The proposed method makes full use of LED light projection invariance,and completes the construction of virtual line by means of imaging sensor communication(ISC).Then,neural network estimation is used to extract information from the virtual camera direction lines.Finally,a simple mathematical equation is adopted to estimate the position of the user indoor.Four situations have been considered in the simulation experiments and the results show that the proposed method outperformed state-of-art techniques and its location error is less than 35 mm for most of the space within a room.

Rapid Construction of Mine Line Infrastructure Using Low-altitude Unmanned Aerial Vehicle Photogrammetry

ZHANG Jianyong, ZHAO Yanling, XIAO Wu, CHEN Yongchun, LI Wenshun, TIAN Shuaishuai, WANG Xin

2017, 0(10):  106-110.  doi:10.13474/j.cnki.11-2246.2017.0325

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Mine line infrastructure is an important part of production and construction for mining.It is restricted to effectively monitor by elongated features and limited surveying employees.Low-altitude unmanned aerial vehicle(UAV) photogrammetry has a series of characteristics,such as rapid response,short revisit,high accuracy,easy operation and low cost,which makes it possible to rapid monitoring of mine line infrastructure.This paper takes the line infrastructure from typical high-groundwater area of underground mine as example,including special railway of mine and controlling-flood dam,designs three experiments of flying altitude (above-ground-level:50,75,100 m),rapidly rebuild the model of mine line infrastructure,evaluates both horizontal and vertical accuracy of models,tests the reliability of models,and discusses the trade-off of cost and efficiency for UAV photogrammetry.The results show that low-altitude UAV photogrammetry can effectively construct the terrain of mine line infrastructure for centimeter-level,model accuracy could meet the requirement the large scale of 1:500 in horizontal level and 1:1000 in vertical level,respectively.Vegetation coverage has an evident influence on elevation values of model,and spatial relation of models is reliable.It proposes that 100m of above-ground-level is an ideal choice after trade-off of cost and efficiency.Therefore,it should combine strengths of UAVs with traditional methods to provide a strong guarantee for rapid monitoring of mine line infrastructure.

3D Model Multi-scale Reconstruction Based on Cloud Point and HD Video

ZHU Li, HU Tao, ZHENG Minghui

2017, 0(10):  111-114,119.  doi:10.13474/j.cnki.11-2246.2017.0326

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In this paper, we propose a 3D model reconstruction for different types of cultural heritage based on cloud point and HD video. The three-dimensional reconstruction technology with multi-resolution on the basis of three-dimensional point cloud and high definition image data is described firstly. Then, we describe the method of cultural relics model fusion and display based on location. In this paper, the proposed method is employed to display of Tangya Tusi castle ruins which is the world's cultural heritage. Shiren, shima, arches and other relic's model were rebuilt according to the fine cultural relics virtual reconstruction method. Through model fusion the multi-resolution digital presentation for Tangya Tusi castle ruins was completed.

A Multi-sensor Remote Sensing Image Automatic Matching Method Based on Topological Information and SIFT Features

DU Chunpeng, LI Jingshan

2017, 0(10):  115-119.  doi:10.13474/j.cnki.11-2246.2017.0327

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Based on the question of matching method of single feature matching in multi-source remote sensing images are often not ideal, a matching method for combination of topology information and SIFT automatic feature of multi-source remote sensing image is proposed in this paper. The method first in two images using the SIFT algorithm in scale space to extract feature vectors, then these feature points using the nearest neighbor the extraction of 1:N multiple possible matching points. Secondly, the matching points are eliminated by the combination of location information and topological information, and the double edge matching strategy and the RANSAC method are used to eliminate the coarse tea. The experimental results show that compared with the SIFT algorithm commonly used in the field of computer vision, the proposed method can effectively improve the matching accuracy and obtain more correct points of the same name.

A New Algorithm for Regional Ionosphere Model Based on the Satellite Trajectory

WU Han, WU Yanping, WU Yajun, KONG Jian

2017, 0(10):  120-123.  doi:10.13474/j.cnki.11-2246.2017.0328

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A new algorithm for regional ionosphere model based on the satellite trajectory is proposed in this paper. The algorithm principle is presented in details. In experiment, the IGS SHAO data are used to analyze the accuracy. The satellite-station model could present the abrupt variation of electron density. The model accuracy is within 1~3 TECU.

Research on Finite Element Model for Large Span Steel Truss Bridge Construction Deformation Monitoring

SHI Huasheng, WU Zhaofu

2017, 0(10):  124-127.  doi:10.13474/j.cnki.11-2246.2017.0329

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Bridge is an important part of transport network. At present, China's engineering construction is developing rapidly, with an endless stream of large span bridges, bridge engineering quality level proposed new requirements. In this paper, establishing efficient finite element model for large span steel truss bridge construction monitoring using the finite element method. Deducing steel truss bridge deflection changes in working conditions of off the shelf through theoretical analysis and model calculations. The results show that the model can preferably predict steel truss beam deflection changes on the natural conditions, meet the actual variation, and thus greatly help to ensure construction safety.

A High Precision Measurement Design to Obtain Super Instrument Height

MA Na, LUO Hongbin, LIANG Jing, KE Zhiyong, HE Zhenqiang

2017, 0(10):  128-132.  doi:10.13474/j.cnki.11-2246.2017.0330

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Since the accuracy of centering leveling and instrument height measurement is poor when the permanent point of device area in tunnel of the Chinese spallation neutron source (CSNS) being observing in the conventional GPS tripod observation mode, a high precision measurement scheme is proposed. In the scheme, the fine-tuned roof bracket and the hemisphere plumbing mirror are designed to ensure stable placement and precise alignment. GPS antenna head bracket is modified to be suitable for placing the target ball and use laser tracker to obtain high precision large instrument height. Finally, six permanent points are measured twice individually using laser tracker which result is compared with the measurement result using the ruler. The results show that the scheme can achieve a high accuracy of 0.5 mm in centering and 0.2 mm in height measuring, which avoids the influence of stretching using ruler to measure, and effectively improve the precision of centering and large instrument height measurement of the permanent point of device area of the CSNS. In addition, the new scheme also provides reference for centering and instrument height measurement of similar points.

Design and Development of Foshan Big Data Map System for Tax Source Data

XIE Huirong, QIAN Pei, XIE Gangsheng

2017, 0(10):  133-136.  doi:10.13474/j.cnki.11-2246.2017.0331

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It is an important mission that how to mine the big geography data to build smart cloud platform for space-time big data.Directed against business requirement for Foshan tax office, this paper makes a study for design and development of Foshan big data map system based on GIS big Data with Hadoop and achieve big tax data's storage, calculation and analysis using the Internet cloud platform.

A Fast Modelling Method Based on 3D Laser Scanning Technology

NAN Junxiang, LIANG Shuang, LI Haiquan, ZHOU Lei, ZHOU Xibing, DANG Junyong

2017, 0(10):  137-139,147.  doi:10.13474/j.cnki.11-2246.2017.0332

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According to the fact that traditional cultural relics 3D modeling method causes many problems, such as, long time, big workload and large expenditure. This paper puts forward to use Z+F 5010C 3D laser scanner patch cloud and panoramic photos, through the color point cloud to accrete directly into a method of the model. The experimental results show that the method making model can reflect the texture details, its quality and scanner is inversely proportional to the distance from scanning the theme, and is closely related to panoramic picture quality. Is presented under the premise of guarantee the point cloud density, by raising the panoramic photos of ways to improve the quality of modeling idea, put forward the direction for further research references.

Application of Air Survey in the Surveying Region with Sparse GCPS Based on Domestic SWDC Aerial Camera

ZHANG Jianxia

2017, 0(10):  140-142.  doi:10.13474/j.cnki.11-2246.2017.0333

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The field surveying workload is sharply reduced with sparse control photogrammetry. It is possible for the realization of sparse control photogrammetry with the development of GPS aided by air survey. This paper dwells on the theory, the technology flow of GPS-aided triangulation, and classical photogrammetry test in the surveying region with sparse GCPS based on SWDC digital aerial camera. The test result shows that the surveying precision of SWDC meets the demand of the topographic survey with the scale of 1:10 000. Furthermore, it is testified that the domestic SWDC is able to the application in the surveying region with sparse GCPS.

Design of Large Data Center Construction for Smart City

KONG Lingli

2017, 0(10):  143-147.  doi:10.13474/j.cnki.11-2246.2017.0334

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The paper analyzes the classification and characteristics of big data of smart city, and designs the smart city data model based on distributed storage and cloud computing technology. The model can efficiently organize and store the key data components of smart city such as geographic data, business data and real-time data, and use the model to build a framework of smart city data center.

Investigation on Curriculum Construction of Spatio-temporal Database for Major of National Geographic State Monitoring

ZHANG Penglin, DU Juan, YU Changhui, ZHOU Junqi, AI Mingyao

2017, 0(10):  148-150,154.  doi:10.13474/j.cnki.11-2246.2017.0335

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According to the characteristics of the major of National Geographic State Monitoring, aiming at the plan and objectives of the major of National Geographic State Monitoring, combining the teaching and practice of the spatio-temporal database course, this paper investigates the instructional objectives, characteristics contensts and content construction. Moreover, teaching methodology and practice teaching are also the main content in the paper. The purpose of the paper is to provide some useful suggestions for curriculum construction of spatio-temporal database.

A Quantitative Assessment System for the Whole Processing of Topographic Survey Practice from Competition

LIU Shanwei

2017, 0(10):  151-154.  doi:10.13474/j.cnki.11-2246.2017.0336

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In view of the problems existed in the course assessment of topographic surveying practice, the assessment system is built with the features of proceduring and quantification. Assessment content is set up focusing on students' practical ability. Diversified evaluation methods throughout the whole process of practice is formed and a quantitative performance evaluation standard is developed. The system can guide the students from passive learning to active learning and make the test from summative assessment to formative assessment. As a result, students' ability of practice and solving practical problems is strengthened, and the training mode of Surveying and Mapping Science in engineering education accreditation environment is consummated.