Table of Content

25 September 2018, Volume 0 Issue 9

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Multipath Error Analysis of Single Frequency Navigation GNSS Receiver in Typical Urban Environment

SHAO Mengyang, GUO Lei, WANG Fuhong

2018, 0(9):  1-7.  doi:10.13474/j.cnki.11-2246.2018.0269

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In the complex urban environment such as tall buildings and trees,multipath error and non-line-of-sight(NLOS) signal error can't be modeled accurately,which badly affect the accuracy and usability of pedestrian GNSS navigation and positioning.This paper comparatively analyses the characteristics of multipath error and NLOS signal error at first,and then separates multipath error and NLOS signal error using double difference observation equation to analyze the influence on pseudo range,carrier phase and doppler of two kind error.By analysing the data measured by UBLOX-NEO-M8T single frequency navigation GNSS receiver beside tall buildings or trees,the results show that Doppler noise is significantly larger when C/N0 is small.For M8T navigation receiver,Doppler noise becomes larger when C/N0 is lower than 30 dBHz under Multi-path seriously affected environment.The relationship between Doppler noise and C/N0 is not obvious under NLOS seriously affected environment.Doppler noise is still significant when C/N0 is larger.Satellite signal is mainly affected by the multipath effect when the trees are obscured,which causes pseudo range error is between 10~150 m,and the impact on phase and Doppler is not obvious.Satellite signal is mainly affected by NLOS when tall buildings are obscured,which causes the same effect on pseudorange and carrier phase observations.The amount of the delay depends on the distance between the reflection point and the receiver,sometimes can reach a few hundred meters.Doppler observations also have a significant impact.

Research on Underground Positioning Algorithm Based on Inertial Sensors

YUAN Debao, ZHANG Fanyuyang, ZHOU Zhenqing, LIANG Chen

2018, 0(9):  8-12.  doi:10.13474/j.cnki.11-2246.2018.0270

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Positioning signals in the underground environment without navigation satellite system leads to common ground location methods which can not be used in underground space.Traditional dead reckoning by cell phone usually requires fixed its attitude or combined with other wireless location methods to correct gait and positioning error.In order to facilitate people to use,reduce the extra hardware layout and avoid interference between wireless signals,this paper improves the gait detection algorithm to eliminate the influence of cell attitude on gait information and takes advantage of the characteristics of people walking path in underground space.The cumulative error is corrected based on the direction of the path,and good results are achieved.This paper selects the ground floor of the teaching building as the experimentation area.When the sampling frequency is 50 Hz,the average positioning error is less than 2 m.

Stability and Precision Analysis of BeiDou+GLONASS+Galileo Multi-system Combined SPP

BU Jinwei, ZUO Xiaoqing, JIN Lixin, LI Haiqiang, ZHOU Yujia, CHANG Jun

2018, 0(9):  13-18,23.  doi:10.13474/j.cnki.11-2246.2018.0271

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Based on the indirect adjustment method and the principle of least squares,the mathematical model of the combined standard single point positioning (SPP) of BeiDou+GLONASS+Galileo system is deduced.Then,using the observation data from some stations of the MGEX station,authors comprehensively analyze the number of visible satellites,DOP values,positioning stability,and positioning accuracy from different combinations of BeiDou,GLONASS or Galileo.The experimental results show that the DOP values of the BeiDou+GLONASS+Galileo three-system combination is reduced by 30%~55% and 10%~50% respectively compared to the single system (BeiDou,GLONASS,Galileo) and the dual system (BeiDou+GLONASS,BeiDou+Galileo,GLONASS+Galileo). Visible satellites increased by 60%~120% and 10%~110% respectively.In addition,with a cut-off elevation angle greater than 30°,the DOP values of single-system and dual-system are large and fluctuating.The positioning reliability and epoch availability are significantly reduced,while the BeiDou+GLONASS+Galileo combination can still get better positioning results.This has practical application value under the harsh conditions of building-intensive areas,mountains and satellite shelters.

Automatic Road Extraction from High Resolution Remote Sensing Images Based on Vector Data Guidance

CHENG Xiaomeng, ZHENG Hao, SUI Haigang, FENG Wenqing

2018, 0(9):  19-23.  doi:10.13474/j.cnki.11-2246.2018.0272

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It is of great practical significance to extract road information from high-resolution remote sensing images.In view of the fact that the existing image classification methods can not directly obtain the high-precision road network information and the degree of automation is low,this paper presents a road extraction method based on the OSM (OpenStreetMap) vector road network guidance to achieve fast and accurate automatic road extraction of high resolution remote sensing images.Firstly,remote sensing images are preprocessed by the gray morphological corrosion,expansion and opening and closing operations.Through the prior information provided by the OSM network,the fuzzy C-means algorithm is improved and the input remote sensing images are roughly divided into three categories.Then the rough classification results are taken as the classification features,and the road samples are automatically selected by the OSM vector network.Using support vector machines for fine classification,and the optimal classification parameters are selected by means of the particle swarm optimization.Finally,we post-process the classification results to get a complete road network.Experiments using two groups of Google Earth images show that the proposed algorithm outperforms the comparison algorithm in the accuracy of road network extraction.

Review of Remote Sensing Monitoring of Crop Pests and Diseases

JIAN Junfan, HE Hongchang, WANG Xiaofei, LI Yue

2018, 0(9):  24-28.  doi:10.13474/j.cnki.11-2246.2018.0273

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Monitoring and early warning of pests and diseases in crops is an important direction in precision agriculture,which can effectively improve grain yield and quality.From the principle and technical route of monitoring crop pests and diseases with hyperspectral remote sensing,this paper first expounds four spectral feature extraction and transformation methods,including the derivative transformation and logarithmic transformation of original spectra,the characteristic parameters based on spectral position and area,the feature parameters of continuum removal,and the vegetation indexes.Then this paper discusses three inversion methods,including the statistical analysis,the machine learning and the physical model,by which the regression relationship between spectral reflectance and pest monitoring parameters is established.Finally this paper analyzes the advantages and problems of using hyperspectral remote sensing technology for crop pests and diseases monitoring.

Remote Sensing Image Change Detection Based on PLS and EM Algorithm

ZHENG Zhifeng, CAO Jiannong, ZHANG Wenjiao

2018, 0(9):  29-33.  doi:10.13474/j.cnki.11-2246.2018.0274

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In high resolution remote sensing images,there are lots of data redundancy and the small scale change threshold is difficult to accurately determine.To solve that problem,a high resolution image change detection algorithm based on partial least squares (PLS) and local maximum expectation (EM) is proposed.First,the remote sensing images of the multi band of the front and back phase are two sets of multivariate variables.Through multivariate statistical analysis of PLS transformation model,effective components are extracted and differential images are constructed by difference method.Then,the regions with relatively large local variations are used to propose the threshold of change detection for different images by EM algorithm.Finally,using the threshold determined by the local image,the whole difference image is divided into two categories:change and non change.And the filtering operator is applied to deal with the detection results.The experiment of high resolution remote sensing image data shows that the method can extract the change information of surface cover better by using multi spectral image,and it has certain application value for dynamic monitoring of geographical conditions.

Remote Sensing Image Registration Based on Non-subsampled Contourlet Transform and Improved SIFT Matching Algorithm

SONG Jiaqian, WANG Xiyuan

2018, 0(9):  34-38.  doi:10.13474/j.cnki.11-2246.2018.0275

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Based on the advantage of non-subsampling contourlet transform (NSCT) in image decomposition and improved SIFT algorithm,a new method of registering remote sensing images is proposed in this paper.First,the remote sensing image to be matched and the reference image are decomposed by NSCT.Two low-frequency images of remote sensing images are acquired.Secondly,the Canny edge detection is used to require the edge coordinates of image,this points is contrasted with the coordinates of the key points detect by SIFT which can remove some unstable response points.Finally,use the RANSAC algorithm to remove the wrong point,the rest of the points are used to match remote sensing images.The experimental Results show that the new method can efficiently decrease remote sensing image matching time by only use SIFT algorithm and increase the accuracy of remote sensing image matching.

Analysis of the Expression Accuracy about Topographical Factors in Multi-sources DEM Data

WANG Ning, LIU Wanqing, YAO Zhihong, LIU Chunchun

2018, 0(9):  39-44.  doi:10.13474/j.cnki.11-2246.2018.0276

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In this paper,under the different grouping conditions,DEMs constructed by ZY-3 stereo images,containing SRTM and ASTER GDEM,compare their slope and slope length to the reference DEM which is constructed by 1:10 000 digital topographic maps. The results show that the 10 mresolution DEM constructed by ZY-3 data shows the highest quality. Increasing the number of control points and the resolution of DEM production don't improve the quality of the data. The 30 m resolution SRTM and the ASTER GDEM_v2 show the absolute advantages at altitudes of 1000~1100 m,but the 10 m resolution DEM constructed by ZY-3 data does well at altitudes of 1100~1300 m and in different land use groups. Established the similarity evaluation index——SI which is based on multiple sets of sample data. SI could evaluate the similarity quantitatively between the reference sample data and the experimental sample data by synthesize the Mean and SD. SI is an important indicator that quantitatively reflects the similarity between data sets.

A Model Point Cloud Compression Algorithm Using Vector-angle Method

LIU Jigeng, WANG Xiaohong, WANG Dongdong, DENG Shixiong, YAN Xingguang

2018, 0(9):  45-49,73.  doi:10.13474/j.cnki.11-2246.2018.0277

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Aiming at the problem of overdense and redundant information of scattered point cloud data,this paper proposes a fast compression algorithm of scattered point cloud based on adaptive slice and vector angle method,which uses slicing technique to stratify point cloud into a slice point cloud.Then,the vector angle method is used to simplify the data for each point cloud.This paper uses this algorithm to carry out experimental research,discusses the influence of the shortest distance and angle parameters on the compression result,and verifies the compression effect by constructing the mesh model.The result shows the algorithm has better compression effect on complex target features realizing fast compression of point cloud. In the meantime,there is no distortion due to excessive compression.The algorithm can adapt the adaptive reservation to reflect the target feature and the detail point,and realize the rapid compression of point cloud.

Land Use/Land Cover Classification Based on Transfer Learning

LI Hailei, HU Xiaojuan, GUO Hang, WU Wenjin

2018, 0(9):  50-54,73.  doi:10.13474/j.cnki.11-2246.2018.0278

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Land use/land cover classification of small sized datasets cannot be accurately and automatically classified by deep learning method.In order to solve this problem,a land ues/land cover automatic classification algorithm applying the reduced-modified deep residual neural network(Resnet-50) for the transfer learning is proposed.Firstly,use the original remote sensing data provided by Sentinel-1 satellite to create dataset.Secondly,compress convolution template numbers of per convolution layer in Resnet-50 and cascade the adaptive networks behind to the obtained reduced residual network.Finally,pre-training the network with ImageNet dataset and transferthe trained model to the Sentinel-1 dataset to fine-tune the parameter of the network.And the high-precision automatic classification of land use/land cover employing deep learning on small datasets is finally achieved.Experimental results show that the classification accuracy of this algorithm on SAR data set is 95.15%,which verifies the feasibility of the proposedalgorithm.

Sentiment Analysis and Recommendation Algorithm under Deep Learning

GUO Hui, LIU Lin, LIU Xiao, CHENG Peng

2018, 0(9):  55-58.  doi:10.13474/j.cnki.11-2246.2018.0279

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With the popularity of online food trading,rapid increase in user evaluation data,it is more and more necessary to make full use of evaluation information and analysis the potential value in a large number of comments.Traditional sentiment analysis can only identify the overall praise or poor evaluation,can not understand the deep demand of users to make accurate recommendations.In order to solve this problem,a recursive neural network for multiple attribute clustering weighting output model is proposed in this paper.According to attribute words,the model excavates characteristics of the user's interest points.A recommendation algorithm based on user interest points and shop's characteristics.The test results show that the proposed model has a high precision and recall for emotional classification,can accurately capture interest point,can improve the effect of personalized recommendation.

Edge Detection Method for SAR Image Based on Improved Ball Tensor Voting

ZHANG Ying, LI Aixia, ZHAO Hong

2018, 0(9):  59-63.  doi:10.13474/j.cnki.11-2246.2018.0280

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Tensor voting is a robust method for feature extraction,which collects the tensor information in neighborhood based on the principles of smoothness,proximity and connecting,and then detects the geometric structures.According to the results of ball tensor voting,we propose an edge detection method for SAR image based on the iterative ball tensor voting in the paper.The edge detection method votes for the iterative ball tensor on the basis of a certain scale range.Using a generalized nonlinear mapping function,the eigenvalues of each pixel were enhanced in the process of iteration,which increased the accuracy of the edge detection.The proposed method has been tested by the real SAR images,and the results of the experiments demonstrate its effectiveness and superiority in terms of the accuracy and integrity of the edge location.

Singular Spectrum Analysis for Dam Deformation Time Series

LI Shiyou, WANG Fengwei, SHEN Yunzhong

2018, 0(9):  64-68.  doi:10.13474/j.cnki.11-2246.2018.0281

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In order to study the properties of dam deformation and corrsponding influence factors,we extract the trend and periodic components of deformation series by singular spectrum analysis(SSA).The correlation coefficient between the components and the aging,temperature and water level factors are calculated.Experimental results show that the dam has creep and periodic elastic deformation.Among them,the creep is mainly related to the time efficiency factor.The periodic elastic deformation is mainly related to the period of temperature and water level factors.Besides,the contribution of the temperature factor to the elastic deformation is greater than the water level factor.The deformation series of the dam are fitted and predicted by the trend and period of extraction.The fitting and prediction errors are 0.52 and 0.24 mm.The traditional multiple regression model is used to fit and predict,the errors are 0.81 and 0.57 mm,respectively.The results show that in this study the singular spectrum analysis can predict the dam deformation more accurately than traditional multiple linear regression method.

Design and Implementation of Space-time Coverage Capability Evaluation and Optimum Combination Observation System for Satellite Sensor

CHEN Nengcheng, LIU Xiaolin, GONG Jianya

2018, 0(9):  69-73.  doi:10.13474/j.cnki.11-2246.2018.0282

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Satellite sensor is one of the most important means of earth observation.To effectively select and combine multi-satellite sensors to meet the needs of specific observation tasks,a satellite sensor coverage assessment method based on the principle of maximizing spatio-temporal coverage is proposed.This method selects the sensor with the largest spatial coverage in each observation period to complete the optimum combination of sensors.The satellite sensor coverage evaluation and optimal combination observation system is designed and implemented.The satellite sensor modeling,the definition of the observation subject,the evaluation of the sensor coverage ability and the sensor optimal combination were achieved.Finally,with an experiment of emergency rainfall observation in the lower reaches of the Jinsha River Basin,the practicability of the system was verified.

Design and Performance Test of BDS Ground-based Augmentation System Based on Symbiotic FM Data Broadcasting

ZHANG Guanghua, ZHANG Quande, MEN Aidong

2018, 0(9):  74-78.  doi:10.13474/j.cnki.11-2246.2018.0283

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This paper explores the Kinhood System (BDS-CDRadio) generated by a cross-domain technical innovation of the symbiotic FM data broadcasting technology (CDRadio) and BeiDou Satellite Navigation System (BDS).The system uses CDRadio broadcast technology to transmit differential correction data of GNSS.With a typical information sharing nature,it has no user scale limits,no concurrency constraints that normally happened in a communication system,and makes a short time-delay which is stable and reliable.The Kinhood transmitting section basically shares original radio broadcast facilities with a small input but wide coverage,which provides extremely low cost,high precision and real-time services of GNSS for massive numbers of receivers.The top third-party authorized tests by Academy of Broadcasting Planning and National Geomatics Center of China prove that:the Kinhood symbiotic digital broadcast keeps the analog FM signal quality in line with the national FM standard,and the digital signal coverage is same as that of analog FM signal at the digital-analog power ratio of -20 dB.The Kinhood System has ideal ground-based augmentation results,especially in the high dynamic scenarios,differential correction data receptions from the radio broadcast enjoy higher stability than the mobile communication transmission.

Function Model of Near Time Estimation of BDS Clock Difference and Its Implementation

NING Wei, TANG Longjiang, JIAO Minglian

2018, 0(9):  79-81,125.  doi:10.13474/j.cnki.11-2246.2018.0284

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In order to obtain high reliability and accuracy of zenith tropospheric delay more quickly,the paper proposes a parameter estimation method.The method chooses epoch-differenced and undifferenced function model and estimates BDS/GPS satellites clock difference using the near time way.45 MGEX tracking stations distributed globally are selected.Initial orbit information of clock difference estimation used the ultra rapid orbit products released by GFZ and used post products as reference values.The experimental results show that the accuracy of GPS satellite clock difference is better than 0.06 ns,and three kinds of BDS satellites clock difference are between 0.04~0.08 ns,which is a little worse than Global Positioning System (GPS).Apparently,the estimated BDS clock difference meets the demands of computing quasi real-time zenith troposphere delay.

Inversion of Leaf Area Index Based on Extreme Learning Machine Regression in Road Vegetation

LEI Yubin, ZHU Shankuan, GUO Yunkai, LI Danna, LIU Lei, LIU Ning

2018, 0(9):  82-86.  doi:10.13474/j.cnki.11-2246.2018.0285

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The acquisition of LAI of road vegetation has an important implication for the monitoring of road vegetation growth and health status.Based on the GF-1 image data and the ground synchronous measured LAI data,the technology of extreme learning machine (ELM) was introduced to inversion modeling in the high-speed road area of Hunan Province.Compared with the traditional empirical regression and support vector machine (SVM) methods,the extreme learning machine is higher,RMSE is 0.501,and the prediction accuracy is 86.26%.The study can provide a reference for road vegetation health assessment.

Application of Unmanned Aerial Vehicle Aerial Photogrammetry in Island

ZHANG Kai, ZHANG Haoyun, LU Xusheng, YOU Hua, XUE Bin, ZHAI Jingsheng

2018, 0(9):  87-90.  doi:10.13474/j.cnki.11-2246.2018.0286

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In order to improve the efficiency of island topographic measurement,this paper presents an unmanned aerial vehicle (UAV) aerial photogrammetry application in island.Based on the principle of three-dimensional (3D) reconstruction,UAV aerial photogrammetry constructs a 3D island model by analyzing massive photographic images acquired via UAV.Compared with the traditional means of island measurement,it has more excellent performance in automatization,accuracy,cost and operation.To begin with,the technical principle is discussed in this paper.Besides,we described its operation process and application in island measurement.The quality of the island 3D model was also evaluated.

Application of Backpack-mounted 3D Mobile Scanning Systems

YANG Ming

2018, 0(9):  91-95.  doi:10.13474/j.cnki.11-2246.2018.0287

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In this paper,we study three current representative Backpack-mounted 3D mobile scanning systems and analyze the key technics used in these devices. Then we verify the precision and efficiency of such devices through the data acquisition test methods. The results show that these devices can achieve the requirements of general surveying and mapping projects such as the standard of large scale topographic surveying and mapping, on which the precision is better than 5 cm in the positional and spacing domain. Nevertheless the elevation precision of these devices doesn't achieve the requirements. In addition,compared with the traditional methods,there are obvious advantages in the operation efficiency. In the future,the integration of multi-sensor and multi-location algorithms is one of the key trends for the application of such devices.

Key Issues of Conceptual Framework for Urban Address Model in China

ZHANG Zhijun, QIU Junwu, KANG Mengjun, MAO Haichen

2018, 0(9):  96-102.  doi:10.13474/j.cnki.11-2246.2018.0288

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As a natural language form of place location,address plays an important role in spatial data infrastructure.In China,large amount of non-standard address data is collected and stored into spatial database to provide data services to organizations result from the relative backwardness of urban planning.These address data reduce the data quality of spatial data infrastructure severely.In this paper,some key issues of conceptual framework for urban address model is discussed,such as the definition of address,the relationship between addresses and geographical features,the better choice of organization who can charge address management and the development situation of address standardization in China.Some new ideas are expected to provide for further research on urban address based on the results of this paper.

The Real Solution of Length Ratio and Meridians Convergence Based on Complex Function

JIN Lixin, WEI Guihua, XU Changwen

2018, 0(9):  103-107,147.  doi:10.13474/j.cnki.11-2246.2018.0289

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On the basis complex function representation of Gauss projection,the definition and formula is given based on the complex reduced latitude.Secondly,based on the complex reduced latitude,the complex function representation is deduced about the length ratio and meridian convergence angle.Finally,the calculation formula is given about Gauss projection,get the real solution of length ratio and meridians convergence.Based on the complex function latitude,Gauss projection calculation accuracy is not limited by the projection zonewidth and has a certain improvement for Gauss projection theory.

Study on the Uneven Settlement of Beijing Plain Area

ZHENG Jiarong, GONG Huili, LI Qingyuan, CHEN Beibei

2018, 0(9):  108-111.  doi:10.13474/j.cnki.11-2246.2018.0290

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In this paper,the results of PS-InSAR monitoring in Beijing plain (2003—2009) combined with GIS spatial analysis is used to analyze the differential settlement.Based on the comprehensive analysis of geological structure data,water source data,road network data and uneven settlement data,this paper studies the factors of uneven settlement in Beijing plain.The study shows that the uneven settlement mainly caused by geological structure,especially the difference in thickness and lithology of the Quaternary sediments.A large amount of continuous extraction of groundwater and the increase of the ground dynamic load make the water level of the compressible layer decrease passively,which leads to persistent stress transfer and large area of uneven settlement.

Discussion on the Method of Ecotope Comprehensive Evaluation for Tibet Plateau Ecological Shelter Zone

WANG Tiejun, ZHAO Lijian, ZHANG Xi

2018, 0(9):  112-116.  doi:10.13474/j.cnki.11-2246.2018.0291

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Starting from the connotation of ecological environment evaluation,and according to the characteristics of natural ecological environment of Tibet Plateau ecological shelter zone,this paper discusses the methods of ecotope comprehensive evaluation for Tibet Plateau ecological shelter zone,which include evaluation index system establishment and index weight determination,evaluation unit selection,evaluation mathematical model research,etc.Then,the ecological environment quality of Tibet Plateau ecological shelter zone is evaluated objectively by using the general survey results of first national geographic conditions and various thematic data.Finally,the evaluation results are analyzed,and some ecological environment problems of Tibet Plateau ecological shelter zone and its protection are pointed out.

Research on Chang Analysis in Urban Spatial Pattern Based on the Result of Geographical Condition Census

XIONG Changxi, DOU Xiaonan

2018, 0(9):  117-120.  doi:10.13474/j.cnki.11-2246.2018.0292

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Taking the city of Zhengzhou as an example,combined with the China geographical condition census and monitoring result,this paper extracted the boundary of urban built-up areas by using the category,location and range of humanity and geographic element,as well as the contemporaneous urban economic and population statistics data.Subsequently,this paper analysed from four sections including the urban area expansion,urban land use efficiency,urban spatial expansion coordination and urban spatial structure and morphological change.The urban spatial pattern expansion and its change rule of Zhengzhou during the year of 2000—2016 was revealed,and the change trend of monitoring element for the central urban area was forecasted.It can be seen from this article that this research result can provide decision-making basis for the scientific regulation and sustainable development of Zhengzhou.

Assessment of the Value of Vegetation Carbon Fixation and Oxygen Release Services in Tiaoxi River Basin Based on the Results of Geography Census

WANG Yu, JIN Shanshan, FENG Cunjun

2018, 0(9):  121-125.  doi:10.13474/j.cnki.11-2246.2018.0293

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Zhejiang's first census of national geographic condition has comprehensively checked the characteristics of the province's natural and human geographical elements, which can provide powerful data support for the management of resources and environment and the construction of ecological civilization. In this paper, the value of carbon fixation and oxygen release in ecological system of Tiaoxi river basin in Zhejiang province was evaluated using Zhejiang national geographic condition census result, combined with GIS and RS technology. The results showed that the average NPP in Tiaoxi basin was 576.83 gC/m², and the total value of carbon fixation and oxygen release in a year was 4.526 billion yuan.

Research and Implementation of Fuzzy Matching for K-tree Address

LI Xinfang, SONG Zhuanling, CHEN Xueye, HE Biao, LIU Haixing

2018, 0(9):  126-129,155.  doi:10.13474/j.cnki.11-2246.2018.0294

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In the integration of digital city information resources,the address matching is a very crucial basic technology.Due to the complexity of description of Chinese semantics and address,the matching of Chinese addresses is much more complicated than that of English.How to accurately segment words based on mass data of Chinese address and realize fast and efficient address matching is an urgent problem to be solved.Based on the research of existing address coding and word segmentation technology,this paper proposes a combination method based on rules and statistics to implement Chinese address segmentation,and uses K-tree to store the Chinese address and improves the Chinese address matching query Accuracy and efficiency.The method was tested by the prototype system based on 10,000 address data after pretreatment in Shenzhen City to verify the effectiveness of the method.

Research on Decision Support System for Urban Planning Based on 2D GIS and 3D GIS

ZHANG Ping

2018, 0(9):  130-134.  doi:10.13474/j.cnki.11-2246.2018.0295

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Traditional urban planning and management methods can not satisfy the requirements of urban integrated management and delicacy management brought by the rapid urbanization and modernization.The construction achievements of smart city provide a solution for these problems.This paper studies an urban planning decision support system based on 2D GIS and 3D GIS,on the basis of basic geographic information data of smart city spatiotemporal information cloud platform.Then it introduces the overall frame design and database design of this system.Furthermore,the main functions and their application scenarios are discussed in the next section.This system may change the urban planning management mode from traditional management of single project to the modern management of overall layout of urban space form and landscape.

Design and Implementation of Real Estate Cadastral Information Collection Platform in Guangzhou

CHEN Liyan, LIN Hong, SONG Yongxin, ZHOU Hao

2018, 0(9):  135-138.  doi:10.13474/j.cnki.11-2246.2018.0296

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Data standardization and completeness are very import to real estate unified registration.The cadastral surveying and mapping production is the basic data for registration,so how to unified manage is becoming a key issue.Data standard,platform construction and working flow of surveying and mapping production collection are discussed in the paper.The real estate cadastral information collection platform realizes data sharing among government departments and enhances the quality of the service.

Reflections on Higher Education of Surveying and Mapping during Intelligence Age

GAO Jingxiang

2018, 0(9):  139-143.  doi:10.13474/j.cnki.11-2246.2018.0297

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The rapid development of artificial intelligence is bound to promote the transformation of higher education in surveying and mapping.Teaching methods and means will be thoroughly changed and the content and extension of teaching content of surveying and mapping higher education will greatly enriched with the development of technologies,such as navigation and positioning,image measurement,big data and cloud services.In this paper,we think deeply about the teaching relationship,teaching model,the quality of teachers and other basic issues about surveying and mapping.Firstly,we expound the basic understanding about the transformation of teaching relationship and put forward the "Center of Gravity Balance" teacher-student relationship in the intelligent age.Secondly,three aspects of the innovation of surveying and mapping teaching mode are analyzed,including individualized classroom teaching,virtual reality teaching and full time and space intelligent teaching mode.Finally,the paper discussed the requirements of intelligent education on surveying and mapping request to teachers from three aspects:the role of educators,teacher differentiation and countermeasures.In general,artificial intelligence will change the view of time and space,the relationship between students and teachers,the teaching mode of traditional education,and brought new opportunities and challenges to surveying and mapping higher education at the same time.

Teaching Reform of “Internet+Engineering Specialized Course” in Universities

CHENG Xiaoqian, WANG Shuangting, LIU Pei

2018, 0(9):  144-147.  doi:10.13474/j.cnki.11-2246.2018.0298

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With the advent of the "Internet+" era,the emergence of smart phones,the popularity of the network and the rising of big data have brought a great impact on the education of university.Most engineering specialized courses have the characteristics of fast update,wide knowledge,plentiful formulas,dull content and close connection to mathematics.How to complete the crossover of the Internet to the teaching of engineering courses,to enhance the interest of the subject,to improve the students' interest in learning and to improve the quality of teaching,should be considered by the most educators of university.Therefore,this paper analyzes the drawbacks of the current "Internet+Education",taking "photography course" as an example,describes the teaching reform in class teaching,process evaluation,practices.As a good example for the engineering educators in university,it has a certain theoretical significance and practical value.

Case Auxiliary Teaching Method of Error Theory and Surveying Adjustment Course Based on the Project of Multi-source Data

YANG Cancan, DENG Kai, ZHANG Xianxian, LI Deliang, QIAN Ruyou

2018, 0(9):  148-151,159.  doi:10.13474/j.cnki.11-2246.2018.0299

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After discussing the problems which existed in the course content and teaching methods of the theory of error and the measurement adjustment course,this paper puts forward a case auxiliary teaching method based on the project of multi-source data,and expounds the process of implementation.At the last part,the teaching reform effects are analyzed from the survey and mapping ability,multi-source data integration ability and data processing and application ability.The results show that the case auxiliary teaching method can deepen students' understanding of knowledge points,exercise its engineering application ability,and improve their professional level.It's expected to provide references for applied talents training and professional development of surveying and mapping.

Mobile Laser Scanning Technology Combined with Trimble Realworks Application in Highway Survey

WU Shaofeng, DU Hongtao

2018, 0(9):  152-155.  doi:10.13474/j.cnki.11-2246.2018.0300

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The traditional way of road surveying and mapping mainly uses GNSS, total station and level. The data format can only be a single point of coordinate or elevation, and there is a certain general error. In order to improve the data integrity, process simplicity and operational safety of road mapping, we tested the practice and application of ground static 3D laser technology. This paper mainly introduces the application of Trimble Realworks point cloud processing software, TBC advanced version software combined with SLAM mobile scanner in road surveying and mapping, and probes into its external measurement workflow method and precision control means. Through processing and analyzing the point cloud, the road survey, DEM modeling, contour drawing, vertical and horizontal section generation and other surveying and mapping production are carried out. In the later period, the accuracy of the data results is checked. The results show that Trimble Realworks point cloud processing software, combined with SLAM mobile scanner and TBC data processing software, can meet the needs of external data collection, internal data processing and external road layout in highway surveying and setting. It is worth popularizing and applying in highway survey.

Quantitative Assessment of the Growth of Populus Diversifolia by High Resolution Aerial Image

YANG Qingshan, FAN Binbin

2018, 0(9):  156-159.  doi:10.13474/j.cnki.11-2246.2018.0301

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Taking Peacock River bed with serious Populus euphratica decline as the study area, we interpreted aerial images (0.2 m resolution) acquired in July 2016 and UAV aerial images (0.07 m resolution) acquired in August 2017 combining field investigation and plotting. According to the growth state, we divided Populus euphratica into growing well, decay and wither. The results showed that the distribution of Populus euphratica is intensive but serious decline in the study area and the growth trend of Populus euphratica has little change between 2016 and 2017. Secondly, Populus euphratica with well growing state account for 15.87% in the study area, and distribute in the near region of human activities, such as periphery of cultivated land. In addition, the mortality rate of Populus euphratica is 61.63%, and 22.46% of Populus euphratica is endangered, which can be turned into well growth state with timely water recovery.

Application of Airborne LiDAR System in Geological Disaster and Emergency

PENG Jinsong, XU Jun, LI Juan, ZHOU Guangming

2018, 0(9):  160-162.  doi:10.13474/j.cnki.11-2246.2018.0302

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Airborne LiDAR technology, as a new type of active ground measurement method, is able to obtain high-precision Earth's 3D data and characterize the real landform, thus helps to provide observation data directly for landform analysis in the geological field. The paper gives a brief introduction of the composition and principle of the airborne LiDAR system. It deals with the measurement of the Xianshuihe Fault and analyzes the advantages and development prospect of the technology in alpine surveying projects.