Table of Content

25 June 2019, Volume 0 Issue 6

Previous Issue    Next Issue

Indoor multipath propagation characteristics of BeiDou pseudolite signal

WANG Xinyi, PAN Shuguo, YU Baoguo, WANG Yanheng, GAN Xingli

2019, 0(6):  1-4,10.  doi:10.13474/j.cnki.11-2246.2019.0173

Asbtract ( )   HTML  

References | Related Articles | Metrics

BeiDou pseudolite system can be applied to indoor location service because of its strong anti-interference ability and flexible networking capabilities. Multipath effect is the main factor affecting the accuracy of pseudolite positioning. Therefore, mastering the indoor multipath propagation characteristics of BeiDou pseudolite is the premise of suppressing multipath and improving positioning accuracy. In this paper, based on the unique signal system of BeiDou pseudolite, the multipath characteristic parameters such as path loss and power angle distribution of pseudolite signals in indoor environment are studied by ray tracing method. The three-dimensional model of large-scale shopping mall is constructed by Wireless Insite software. The simulation results show that the pseudolite multipath components will decrease sharply under non-line-of-sight conditions and will be distributed in a certain range of horizontal direction angles with similar power values, while the fading channel model obeys the small-scale fading in accordance with the Rayleigh-lognormal distribution, and the large-scale fading coincides with the log-distance path loss model.

Comparison of diffirent fusion methods and their performance evaluation to high spatial resolution remote sensing data of GF

SHAO Yakui, ZHU Changming, ZHANG Xin, SHEN Qian

2019, 0(6):  5-10.  doi:10.13474/j.cnki.11-2246.2019.0174

Asbtract ( )   HTML  

References | Related Articles | Metrics

Choosing an appropriate fusion method is conducive to better serving the practice and scientific research of remote sensing image. This paper tries to find the best fusion method for high resolution remote sensing images of China satellite at the basis of summarizing the existing image pixel-level fusion algorithms. Pansharp, Gram-Schmidt, HPF, Ehlers, Subtractive, Modified IHS transform, Brovey, PCA, NND and etc. methods were selected to fuse the panchromatic and multispectral data of high-resolution images of China satellites, and then 9 fusion results were evaluated qualitatively and quantitatively. The results show that Pansharping algorithm are the best both in the visual effect and the quantitative indicators of image quality evaluation. The results of Gram-Schmidt, NNDiffuse, Subtractive and HPF have the clearest boundary. Moreover, the result of Modified IHS, PCA and Brovey have obvious color distortion. The result of NND is more prominent in the visible band and Gram-Schmidt performs best in near infrared band. The information presented in this paper can provide technical reference for the application and research of GF-1 satellite data in the future.

Remote sensing image water body extraction based on improved watershed

FENG Zhaohui, LI Qin, HAN Liusheng, XUE Guochao, ZHAO Hongying

2019, 0(6):  11-15.  doi:10.13474/j.cnki.11-2246.2019.0175

Asbtract ( )   HTML  

References | Related Articles | Metrics

In view of the incomplete and the misidentification of surrounding objects of water extraction in the current global water environment monitoring, this paper takes the Shandong Weihe River as the research object, and the improved watershed segmentation method designed by this paper is adopted. Firstly, the spectral information component of the target water body is extracted as the foreground image, then use the expanded water object as the background image. And the foreground image and the background image are superimposed to generate a marker image. The marker image is used by the watershed transformation to realize the automatic extraction of the water body information. The results of this paper are compared with the watershed algorithm of manual marker seed point in OpenCV, the watershed algorithm based on Canny edge, the watershed segmentation method combined with morphological filtering and labeling. The experimental results show that the algorithm designed in this paper is more automated than the seed point watershed algorithm in OpenCV. And the extracted water body is more complete and accurate. The method in this paper avoids the over-segmentation compared to the Canny edge method. Compared with the method of combining morphological filtering markers, the method is more complete and accurate in extracting the target water body. In conclusion, this paper's method is an automatic and effective method for water body extraction.

Extraction of remote sensing abundance information of typical vegetation in southern China

GUO Yunkai, LIU Haiyang, JIANG Ming, ZHU Jiaming

2019, 0(6):  16-18,28.  doi:10.13474/j.cnki.11-2246.2019.0176

Asbtract ( )   HTML  

References | Related Articles | Metrics

Aiming at the problem of a large number of mixed pixels in the extraction of typical vegetation abundance in the southern hilly region of remote sensing images, in order to further improve the precision of linear unmixing, the EVI time series curves of typical vegetation (endmember) and mixed pixels in the south of Landsat 8 time series images are constructed by calculating the EVI value of pixels. The vegetation index change curves of various feature types in different growth periods are analyzed, and it is found that different features have their own independent fluctuation rules in the vegetation index time series.By selecting multiple endmembers and their EVI time series curves, the spectral matching method is used to match the EVI time series curve and multiple endmembers, and the purpose of spectral unmixing using different endmember combinations is achieved. The test results show that compared with the traditional method, the precision of broad-leaf forest unmixing is obviously improved, and the precision of coniferous forest unmixing is also improved. The research results can provide strong support for the study of vegetation environment in the southern hilly region.

Remote sensing image aircraft detection supported by deep convolutional neural network

XIE Meng, LIU Wei, YANG Mengyuan, CHAI Qi, JI Li

2019, 0(6):  19-23.  doi:10.13474/j.cnki.11-2246.2019.0177

Asbtract ( )   HTML  

References | Related Articles | Metrics

Aiming at the problem that YOLOv3 (You look only once) algorithm has poor detection of small targets and many missed detection, this paper proposes an optimized YOLOv3 algorithm. Firstly, K-means algorithm is used to calculate the anchor frame suitable for the data set in this paper. Then, extended convolution is introduced into YOLOv3 network to enhance the high-level perception field of the network, improve the detection effect of small targets, and secondly, depthwise separable convolution is used. It replaces the ordinary convolution in YOLOv3 network residual module, reduces the calculation parameters, and thus obtains a new convolution neural network structure. Then the comparative experiments are carried out on the data set in this paper. The experimental results show that the optimized YOLOv3 algorithm can detect more targets and reduce the missed detection rate. Compared with YOLOv3 algorithm, its recall rate is increased by 11.86% and F1-score by 2.99%.

Hyperspectral image classification based on local and structural feature with sparse multinomial logistic regression

SHEN Yuzhen, GUAN Yunlan, YANG Lu, LIU Chengcheng, YAN Xiaofang

2019, 0(6):  24-28.  doi:10.13474/j.cnki.11-2246.2019.0178

Asbtract ( )   HTML  

References | Related Articles | Metrics

Sparse multinomial logistic regression only uses spectral information in image classification.Therefore,the classification effect is poor. In this paper,a hyperspectral image classification method based on local and structural feature with sparse multinomial logistic regression is proposed. Firstly, weighted mean filter and extended multi attribute profiles are used to extract local and structural features of the original hyperspectral images. Then the weighted average feature level fusion is carried out to obtain more unique pixel feat ures.Finally,the fusion results are classified by sparse multinomial logistic regression.The results show that the proposed method has well classification effect and robustness.

The classification by medium resolution remote sensing images based on deep learning algorithm of GoogleNet model

CHEN Bin, WANG Hongzhi, XU Xinliang, WANG Shoutai, ZHANG Yaqing

2019, 0(6):  29-33,40.  doi:10.13474/j.cnki.11-2246.2019.0179

Asbtract ( )   HTML  

References | Related Articles | Metrics

We proposed a remote sensing classification method based on deep learning technology, which can effectively solve the problem of pixel mixing in the medium resolution images classification. The research selected the Landsat 7 ETM+ remote sensing image of Wuhan City on May 12, 2016. Based on the Inception V3 network structure in the GoogleNet model, the remote sensing image classification model was constructed by means of migration learning method, and four typical features of the main urban area of Wuhan were realized. Automatic classification of permeable layers, vegetation, water bodies and other land uses, and the classification results were compared with traditional maximum likelihood classification (ML) results. The research shows that the overall classification accuracy of remote sensing image based on deep learning method is as high as 88.33%, and the Kappa coefficient is 0.834 2, which is obviously better than the traditional classification accuracy of 83% and Kappa coefficient of 0.755 0, and it effectively suppresses the phenomenon of pixel mis-or leakage in the classification process.

Multi-Renyi entropy image segmentation algorithm based on improved fractional Darwin particle swarm optimization

YUAN Yuzhu

2019, 0(6):  34-40.  doi:10.13474/j.cnki.11-2246.2019.0180

Asbtract ( )   HTML  

References | Related Articles | Metrics

In view of the problem that intelligent optimization image segmentation algorithm is easy to fall into local optimal and low segmentation precision, this paper presents a new multi-threshold remote sensing image segmentation algorithm, which combines the improved fractional Darwin particle swarm optimization and the two-dimensional Renyi entropy multi-threshold. The algorithm uses the particle evolution information to define the evolution factor, combines the evolutionary factor and adjusts the fractional coefficients α by using the Gauss graph function to achieve accurate calculation and fast convergence.According to the local optimal probability factor, the Levy flight random disturbance is carried out to improve the ability of the algorithm to jump out of the local optimal. At the same time, the two-dimensional Renyi entropy single threshold is extended to the multi-threshold segmentation, and the improved fractional Darwin particle swarm optimization is used to apply the two-dimensional Renyi entropy multi-threshold to the remote sensing image segmentation.The simulation results show that, compared with the other two intelligent segmentation algorithms, the segmentation algorithm has obvious advantages in detail processing and segmentation accuracy, at least 7.27% increase in PRI, 6.5% decrease in VOI, and decrease in GCE by at least 10.4%.

Research on bridge deformation monitoring based on chaos theory

XU Zhangping, LUAN Yuanzhong, LIU Zhonghua, CUI Tengfei, XIANG Tao

2019, 0(6):  41-46.  doi:10.13474/j.cnki.11-2246.2019.0181

Asbtract ( )   HTML  

References | Related Articles | Metrics

Aiming at the problem of pier nonlinear sinking, chaos theory is introduced. The reconstructed by the improved C-C and the G-P algorithm of time series, compared with traditional algorithms,the anti-interference and computational efficiency are improved. The maximum Lvyapunov exponent is obtained to determine whether there is chaos in time series. Finally,a weighted first-order local prediction model and a RBF neural network chaotic prediction model are established according to the obtained parameters to respectively predict and analyze the observed data. The chaotic time prediction results are compared with those of exponential smoothing method. The prediction precision of chaotic time is higher than that of exponential smooth method,and the predicted precision of chaotic model of RBF neural network is the highest, which proves that the predicted precision of chaotic time series is reliable, and can monitor the deformation of the bridge body in real time to avoid disasters.

Matching algorithms for heterogenous multi-resolution satellite images

HUO Menjie, FAN Dazhao, DONG Yang

2019, 0(6):  47-51.  doi:10.13474/j.cnki.11-2246.2019.0182

Asbtract ( )   HTML  

References | Related Articles | Metrics

In this paper, the image feature extraction, feature description, feature matching and the matching purification algorithm are studied by taking the satellite image of heterogeneous and multi-resolution remote sensing as the research object. Different feature extraction and matching algorithms are combined and the applicability of each algorithm is obtained through experimental comparison. Based on this, a set of matching process for multi-resolution satellite images is designed.

3D measurement method of single oblique aerial image supported by DEM

XIONG Changxi, SONG Bibo

2019, 0(6):  52-56.  doi:10.13474/j.cnki.11-2246.2019.0183

Asbtract ( )   HTML  

References | Related Articles | Metrics

This paper improved a fast measurement method of single oblique aerial photograph supported by DEM. According to the difference of position and attitude between images and buildings, the measurement method of single image is studied, and the calculation formulas are deduced. Then verify the accuracy of the algorithm, and analyze the specific impact factors by selecting test area. The experimental result shows that the horizontal and vertical accuracy of the study area is satisfying, which can meet the application needs of fields such as urban planning and management, and will provide experience and reference for urban 3D data acquisition.

Seamline network generation and optimization for orthoimage mosaicking based on Voronoi diagrams

CHEN Song, ZHOU Ping, LI Xianju, CHEN Gang

2019, 0(6):  57-60,84.  doi:10.13474/j.cnki.11-2246.2019.0184

Asbtract ( )   HTML  

References | Related Articles | Metrics

In this study, a global seamline network generation and optimization method based on Voronoi diagrams is proposed for orthoimage mosaicking. First, from the centers of valid areas for each orthoimage, the Voronoi diagrams algorithm is applied to generate a globally consistent seamline network, determining the mosaic polygon of each orthoimage. Then, vertices of the mosaic polygon are relocated with the use of DSM to avoid holes in the final photomosaic and ensure those vertices are located on the ground area. So that the seamline can avoid crossing objects with large projection difference such as buildings and trees after being further optimized. Experiment results demonstrate that the proposed method is feasible and has good adaptability.

Travel time estimation method of complex route based on geographic grid

WU Yinghao, LI Chengming, WU Zheng, WU Pengda

2019, 0(6):  61-65.  doi:10.13474/j.cnki.11-2246.2019.0185

Asbtract ( )   HTML  

References | Related Articles | Metrics

The travel time of a path implies the traffic condition in period of time. How to calculate this time accurately is of great significance in traffic monitoring and route planning. The existing studies usually use the taxi historical trajectories to estimate the travel time of a path. However, when the path is long, it's difficute to find a historical trajectory pass through the specified path completely, so that we can't estimate the travel time accurately. On the other hand, massive historical trajectories generate huge data management and computational pressure on path travel time estimation. For this reason, we introduce the geographic grid(Cell). First, we construct a unified spatio-temporal index, divide the trajectory data into a series of trajectory segments that fall in the geographic grid (Cell) and split the road network into a series of road patterns that fall in Cell. Then, the travel time of vehicle in current road pattern is represented as the residence time of a series of frequent shared trajectories in Cell. Finaly, we estimate the travel time of vehicles on longer routes using the passage time of a set of similar road patterns in historical periods. At the end of this paper, we verify the effectiveness of our method in dealing with massive historical trajectories and verify the superiority in estimating vehicle travel time on longer paths based on the GPS trajectories of 10 000 taxicabs over a period of one week.

Semantic annotation of travel trail stay points considering geographical context

FAN Hailin, LIANG Ming, LI Jia, DUAN Ping, WANG Shanshan, WANG Tong

2019, 0(6):  66-70.  doi:10.13474/j.cnki.11-2246.2019.0186

Asbtract ( )   HTML  

References | Related Articles | Metrics

As a typical space-time big data, trajectory data has high research and application value. However, the existing trajectory data mining mainly focuses on the spatial features of the trajectory, and less on the depth analysis of the trajectory data semantics. This paper is oriented to the demand of smart travel service, aiming at the semantic annotation of the track stop point, focusing on the automatic labeling problem of the track stay point semantics of the travel track. Firstly, aiming at the characteristics of short text of POI, this paper proposes a method of semantic extension of short text based on "synonym word forest" to extend the feature of POI short text. At the same time, it takes into account the feature set of POI short text and the distribution of category words. In this paper, the POI automatic classification method for improving TF-IDF is proposed. Secondly, based on the POI classification, the Native Bayes method is used to semantically mark the track stay points. The results show that the automatic classification of POI based on the improved TF-IDF method can achieve about 83% accuracy, which can better realize the classification of POI. On the basis of automatic classification of POI, the trajectory semantic annotation based on Native Bayes can reach 74%. The accuracy of the target is automatically achieved by the automatic semantic annotation of the travel track stay point.

Design and implementation of mobile measurement method for smartphone

JIANG Hemin, ZHONG Ruofei, XIE Donghai

2019, 0(6):  71-76.  doi:10.13474/j.cnki.11-2246.2019.0187

Asbtract ( )   HTML  

References | Related Articles | Metrics

In recent years, smartphones have gradually integrated a variety of sensors in the rapid development process, including position sensors, attitude sensors such as magnetometers, accelerometers and digital cameras. At the same time, the advantages of small size and low cost provide the possibility to realize mobile image measurement. A new type of smartphone image measurement method is proposed through the platform of Android system and multi-sensor integrated by smartphones. The method firstly calibrates the smartphone camera to obtain the inner orientation elements, and develops the Android application program which can obtain the position and posture data of the mobile phone while acquiring the image data. Secondly, extraction, matching of feature points and error point deletion are performed on the image data. According to the position and attitude data and the image coordinates of the homonymous points, the three-dimensional coordinates of the target point are calculated by space intersection. Finally, the results of space intersection is taken as the initial value and are overall optimized by the bundle adjustment. The experimental results show that the position information obtained by this method can achieve higher precision.

A fast registration method for UAV video frames

SUN Xinbo, LI Yingcheng, WANG Enquan, GENG Zhongyuan, WANG Sixue

2019, 0(6):  77-80.  doi:10.13474/j.cnki.11-2246.2019.0188

Asbtract ( )   HTML  

References | Related Articles | Metrics

A fast registration method for unmanned aerial vehicle (UAV) video frames was proposed in the paper, according to the need of rapid acquisition and processing of UAV video data in maritime surveys. Firstly,the time synchronization between the video frames and UAV positions and attitude information was realized using the method of time index and linear/spherical interpolation. Then the rough registration of video frames was obtained after geocoding video frames with digital differential rectification algorithm. Finally, the precise registration was obtained by controlling the zoom factor in affine transformation model to adjust geographic coordinates of the processed frames. The results show that this method is qualified for obtaining precise registration of video frames within route.

A novel map matching method of urban road

WANG Jianpei, LI Bijun, ZHANG Hongjuan, ZHANG Ping

2019, 0(6):  81-84.  doi:10.13474/j.cnki.11-2246.2019.0189

Asbtract ( )   HTML  

References | Related Articles | Metrics

The existing map matching method using vertical projection is often difficult to correct the longitudinal error, and the matching effect in the intersection is not good. In this paper, a map matching algorithm is proposed which makes full use of the road constraints at the intersections. We collect the location data of autonomous cars using low-cost integrated navigation method with IMU and odometer,and combine with open source OpenStreetMap for map matching, which breaks the dilemma that the autonomous driving industry is highly dependent on GPS. Experimental results show that the average time of a single point is 0.11 ms, and the proposed method is suitable for urban driving environment and meets the requirement of real-time calculation, and the matching accuracy can reach 100% while the recall rate is 89%.

Detection of flatness and verticality of buildings based on 3D laser scanning technology

WANG Ermin, GUO Jiming, YANG Fei, SONG Shengdeng, YU Xuyang

2019, 0(6):  85-88.  doi:10.13474/j.cnki.11-2246.2019.0190

Asbtract ( )   HTML  

References | Related Articles | Metrics

The point clouds information of the target building is obtained by using terrestrial laser scanner which embodies characteristics such as full automation, high precision, panoramic sweeps. After the analysis and research work, a method of extracting central axis of buildings based on point clouds is proposed. The random sample consensus (RANSAC) is used to fit the straight line. The fitting plane of point clouds adopt a method based on total least squares. The wall flatness and verticality of buildings are detected by analyzing the geometric characteristics of fitting planes and fitting straight lines. The result shows high feasibility and applicability in the detection of the wall flatness and verticality by using 3D laser scanning.

Object-oriented land use/cover classification in coastal area

YANG Xiaoyan, LIU Wenlu, LI Long, CHEN Longqian, CHEN Longgao

2019, 0(6):  89-91,95.  doi:10.13474/j.cnki.11-2246.2019.0191

Asbtract ( )   HTML  

References | Related Articles | Metrics

Land use/cover (LUC) information is a very essential dataset in supporting the related research and application. To extract the LUC information in the coastal area, an object-oriented based classification method is proposed and applied to Lianyungang city using Landsat 8 imagery. The results indicate that the accuracy of the classification exceeded the minimum allowed discriminant accuracy 0.7 with the overall accuracy 85.06% and the overall Kappa coefficient is 0.83. The methodology can reduce the misclassification of arable land due to the vegetation coverage between the southern plains and northern hills, and can be used to extract the tideland and salt-field in the area. The methodology can provide the LUC data with agreed accuracy for the land related research for Lianyungang city, and support the extraction of LUC information in other similar coastal areas.

Key technologies analysis of airborne LiDAR in high accuracy tidal flats DEM production

WEN Xuedong, LI Junfeng, LIN Yun

2019, 0(6):  92-95.  doi:10.13474/j.cnki.11-2246.2019.0192

Asbtract ( )   HTML  

References | Related Articles | Metrics

LiDAR can quickly obtain three-dimensional geometric information of the surface directly. Meanwhile, LiDAR has the great advantages of all-weather, active observing and certain penetration between the surface features gap. In this paper, LiDAR surveying and mapping work experience of Ningbo tidal flats is summarized. Firstly, the superiority of airborne LiDAR technology in tidal flats surveying and mapping is introduced. Then, on the basis of the data processing flow of LiDAR point, the emphasis is focused on key technologies of high precision DEM production. Finally, the accuracy evaluation of DEM products is carried out.

The key technology of disaster geographic information acquisition in UAV cluster and major applications

HUANG Ruijin, SHEN Fuqiang, ZHOU Xingxia, HUANG Qinglun, CHENG Duoxiang

2019, 0(6):  96-99,104.  doi:10.13474/j.cnki.11-2246.2019.0193

Asbtract ( )   HTML  

References | Related Articles | Metrics

The low-altitude remote sensing technology of UAV has been widely used in the fields of emergency surveying and mapping due to its characteristics of flexible maneuverability, high efficiency, accuracy, and little constraint of climatic and airspace conditions. However, due to the complicated and harsh environment, high altitude and cold in the western mountainous area, single machine and single sensor acquisition technology failure to provide timely and efficient protection for emergency rescue, so it is urgent to upgrade the low-altitude remote sensing technology of UAV. Based on the surveying and mapping emergency practice of Sichuan province's, this paper has carried out a lot of research work on the plateau stability operation, single platform multi-sensor, high-speed transmission and other aspects. The achievements played an important role in the emergency surveying and mapping support work of Jiuzhaigou earthquake.

Application of 3D laser point cloud data in the reconstruction of BIM model in existing underground civil defense engineering

MIAO Yazhe, LI Shengbo, DENG Anzhong, LE Guan, DAI Zuoqiu

2019, 0(6):  100-104.  doi:10.13474/j.cnki.11-2246.2019.0194

Asbtract ( )   HTML  

References | Related Articles | Metrics

The creation of BIM model is the first step to the application of the BIM technology. The common method of BIM model creation based on CAD drawing has the disadvantages of low modeling efficiency and terrible spatial performance. Taking the reconstruction of BIM model of an underground civil defense engineering as an example, and combining with 3D laser scanning technology, the BIM model reconstruction process based on 3D laser point cloud data is elaborated, mainly through the following steps. First using FARO Focus^3DX330 to obtain massive point cloud data. Then using FARO SCENE software to complete registration and splicing, filtering and denoising, texture and output. At last according to the differences in the geometric shapes and the functional characteristics of target objects, completing the BIM model reconstruction of linear class, component connection class, and single target class respectively by using Autodesk Revit. The research shows that the reconstruction of BIM model can be completed well by using 3D laser scanning technology, which has the prominent advantages of high modeling accuracy and good field reduction.

Research on the method of point cloud denoising based on curvature characteristics and quantitative evaluation

ZHU Guangtang, YE Minlü

2019, 0(6):  105-108.  doi:10.13474/j.cnki.11-2246.2019.0195

Asbtract ( )   HTML  

References | Related Articles | Metrics

Due to the errors of instrument ranging, angle measurement, reflectivity of objects, artificial operation, occlusion and environmental changes, there are a lot of noise in the point cloud data. In order to remove noise efficiently and keep the feature information of original point cloud data, the thesis proposes a new method of point cloud denoising based on moving least square curvature feature. Firstly, the curvature information of point cloud is accurately calculated by moving least squares method, and then the point cloud is denoised according to the curvature information. Finally, the feasibility of this method is verified by the quantitative evaluation method based on information entropy theory.

Application of vehicle-borne mobile surveying system in the mathematical precision detection of large scale topographic map

LU Yuxiang, WAN Xiaoli, CHANG Cen, ZHU Tingting

2019, 0(6):  109-111,125.  doi:10.13474/j.cnki.11-2246.2019.0196

Asbtract ( )   HTML  

References | Related Articles | Metrics

In order to use vehicle-borne mobile surveying system to detect large scale topographic maps, the relevant experiment is carried out in a small range. When its validity is proved, large scale topographic maps of a whole city is carried out by this method. The vehicle-borne mobile surveying system and the conventional method are compared in the data collection, internal data processing and storage. The paper analyzed the advantages and disadvantages of the method. The results of this experiment provide a new scheme for improving the quality inspection efficiency of surveying and mapping.

Slope deformation analysis and forecast based on ARIMA model

HU Bo, TAN Han

2019, 0(6):  112-116.  doi:10.13474/j.cnki.11-2246.2019.0197

Asbtract ( )   HTML  

References | Related Articles | Metrics

In this paper, the process of stability analysis, model recognition, model evaluation and model prediction in time series analysis is discussed in details. The ARIMA model is established to analyze and forecast the 461 days slope monitoring data from June 29, 2016 to October 4, 2017. The analysis shows that it is feasible to use ARIMA model to analyze the time series of slope observation data and can get a reliable results. The study provides a reference for engineering construction and disaster prevention and mitigation.

Research and application of T-shaped groove smoothness detection method for evacuated tube maglev train

HE Yong, LIU Chenglong, YANG Xuefeng, DUAN Bokai

2019, 0(6):  117-120.  doi:10.13474/j.cnki.11-2246.2019.0198

Asbtract ( )   HTML  

References | Related Articles | Metrics

This paper does some research works of the measurement, analysis and adjustment methods based on T-shaped grooved rail smoothness, aiming at solving the problem that it is difficult to detect and analyze the smoothness of T-shaped grooved rail under construction. The high-precision three-dimensional control network is built in the tube by using the free station measurement technology, which solves the problem that it is difficult to establish the measurement reference due to the limitation of the environmental conditions in the tube. Based on the control network, the three-dimensional coordinates of each measuring point on the grooved rail are measured by using the technique of free station measurement and polar coordinate measurement, which provides the basic data for the analysis of T-shaped grooved rail smoothness. In order to determine the smoothness quality of the grooved rail, the deviation of each measuring point on the grooved rail is quantified into four statistical indexes by statistical analysis method. The results show that the selected four indexes can quantitatively and comprehensively reflect the smoothness quality of the grooved rail. In order to improve the smoothness of the grooved rail, a method is proposed to calculate the adjustment amount based on the deviation of each measuring point on the grooved rail and to fine adjustment. The results show that the method can significantly improve the smoothness of the grooved rail.

Research on non-contact rapid inspection method of high pier bridge verticality and its precision analysis

DING Keliang, LIU Mingliang, LIU Yajie, BAO Dongdong, DONG Jun

2019, 0(6):  121-125.  doi:10.13474/j.cnki.11-2246.2019.0199

Asbtract ( )   HTML  

References | Related Articles | Metrics

This paper proposes a non-contact measurement method which can quickly collect the bridge perpendicularity observation data and solve the problem of verticality detection of high-rise bridges in highways based on the total station free station. This method uses robust least squares method to calculate the bridge verticality parameters to improve the accuracy of the calculation results. The practical application case shows that the new method has advantages of fast speed, high detection precision and good reliability, compared with the traditional methods, which provides a new idea and method for quickly solving the verticality detection of high pier bridge.

Research and application of measuring method for straightness of pressure pipeline in maglev traffic test line

HAN Bing, LIU Chenglong, YANG Xuefeng

2019, 0(6):  126-130,135.  doi:10.13474/j.cnki.11-2246.2019.0200

Asbtract ( )   HTML  

References | Related Articles | Metrics

At present, there are few studies on the straightness measurement of vacuum magnetic levitation pressure pipelines at home and abroad. Combining with the vacuum magnetic levitation high-speed train test device under construction of Southwest Jiaotong University, this paper puts forward a method for measuring the straightness of vacuum pipeline and introduces how to establish a high-precision three-dimensional control network in the pipeline, how to determine the coordinates of the center of each section of the pipe according to the three-dimensional control network and the method of circular curve fitting, and how to do the straight line fitting to analyze the straightness of the whole pipeline. Finally, according to the aboved method, a programis is compiled to process and analyze the measured data, which verifies the correctness and feasibility of the method, and provides reference for the construction of vacuum magnetic levitation pressure pipeline in the future.

The construction of an intelligent platform for all-for-one tourism——taking Guiping as an example

XUAN Qingdong, LUO Qisi

2019, 0(6):  131-135.  doi:10.13474/j.cnki.11-2246.2019.0201

Asbtract ( )   HTML  

References | Related Articles | Metrics

The traditional tourism service model cannot follow the new tourism development trend. Based on mobile augmented reality, hand-drawn map intelligent tour guide, panoramic virtual tour, unmanned aerial photography and other technologies, an integrated, information-based and intelligent solution that integrates tourism information release, system development, operation management and market promotion is proposed. Taking Guiping as an example, the construction mode of all-for-one tourism wisdom platform is put forward. The achievements include a tourism portal website, a tourism WeChat official account, a tourism WAP mall, APP, and an intelligent information release system, etc., which can meet the tourism public service needs of tourists and has positive significance to the development of Guiping's tourism.

Technology of public welfare map adaptively and quickly producting

ZHU Xiuli, LIU Wanzeng, WU Chenchen, ZHAO Tingting

2019, 0(6):  136-139.  doi:10.13474/j.cnki.11-2246.2019.0202

Asbtract ( )   HTML  

References | Related Articles | Metrics

In recent years, the state has become more and more demanding for the rapid guarantee service work of public welfare maps of surveying and mapping product. It shows that the demand for high-potential, high-quality geographic information high-efficiency and spiritual services is becoming more and more urgent. Therefore, research rapid production technology of public welfare maps has also become an urgent requirement. In response to this demand, based on key process, this paper studies the key issues of rapid map production, accordding mapping area and size and so on, deciding scale, map projection, layout, map decoration and data.

CDIO-OBE mode reformation of remote sensing experiment teaching under the background of emerging engineering

LI Gang, QIN Kun, WAN Youchuan

2019, 0(6):  140-145,151.  doi:10.13474/j.cnki.11-2246.2019.0203

Asbtract ( )   HTML  

References | Related Articles | Metrics

Emerging engineering construction is an important deployment of China's talent planning strategy under the situation of new technology, new industry and new economy, which has opened up a new path for engineering education reformation. This paper introduces the new mode reformation of talents training according to the requirements of the emerging engineering construction through the docking of remote sensing experiment teaching with emerging engineering education idea. Using for reference CDIO-the latest mode of international engineering education and OBE-the general mode of American engineering education, the CDIO-OBE mode has been implemented in remote sensing experiment teaching. The CDIO-OBE mode of remote sensing experiment teaching includes the following aspects. Firstly, drawing on the experience of the Washington Agreement System, the EUR-ACE system of the European Union and the standards of engineering education certification of China, the overall outcome of experiment teaching is developed. Secondly, the experiment curriculum system based on the matching matrix between curriculum and learning outcome is optimized. Thirdly, according to the learning outcome of the courses, the teaching content is designed. Fourthly, the course teaching is organized according to CDIO, and the outcome of learning is achieved. The CDIO-OBE mode carries out the overall training of the project and team to realize the learning outcome, and promotes the remote sensing engineering talents' cultivation under the background of the emerging engineering.

Research of innovation entrepreneurship education mode based on engineering technology research center

WANG Yanxia, LI Peng, WU Jian, LIU Yuchan, XU Jianhui, DENG Yuechuan, YANG Haiyan

2019, 0(6):  146-151.  doi:10.13474/j.cnki.11-2246.2019.0204

Asbtract ( )   HTML  

References | Related Articles | Metrics

Under the new situation, innovation entrepreneurship education is an important education idea and mode of training applied talents with high quality in colleges and universities.Due to many problems appeared in innovation entrepreneurship education, this paper proposes a new talent training model of innovation and entrepreneurship. In this paper, the connotation of the engineering technology research center and advantage is introduced, specific implementation plan and implementation effect of entrepreneurship and innovation personnel training based on engineering technology research center are emphatically expounded,taking geographical information and tourism department of Chuzhou University as an example.The results have important reference value,and results indicate that the new innovation entrepreneurship education mode and traditional mode can be effectively complemented and integrated.

Application of 3D laser scanning technology in subway tunnel

JIANG Jiqiang, ZHANG Huijuan, CAO Qianhong

2019, 0(6):  152-154.  doi:10.13474/j.cnki.11-2246.2019.0205

Asbtract ( )   HTML  

References | Related Articles | Metrics

Trimble SX10 scanning total station has the effective scanning distance of 200 m in a single station in the tunnel. It has the characteristics of single operation, custom irregular area scanning, internal data free splicing, tunnel completion report fully automatic generation. Because of its simple operation mode, efficient scanning rate, and convenient internal processing, it is well recognized by the construction companies.

An innovation exploration of big data technology integration for the implementation evaluation of urban comprehensive planning: a case study of Zhuhai

PANG Qiancong, JIANG Wenya, LUO Yong, MAN Deru, CHEN Jiaxun

2019, 0(6):  155-159,162.  doi:10.13474/j.cnki.11-2246.2019.0206

Asbtract ( )   HTML  

References | Related Articles | Metrics

Based on the big data integration application in implementation evaluation of Zhuhai urban comprehensive planning, the paper summarizes the implementation evaluation of the five big data key technologies, combs the related to land use, population, spatial pattern and transportation system, public service, the green space system, and other special big data analysis module, explores a set of big data method to support the implementation evaluation of urban comprehensive planning.

Application of tilt photogrammetry in surveying and mapping of water conservancy projects

WANG Jie, MENG Gaoyuan

2019, 0(6):  160-162.  doi:10.13474/j.cnki.11-2246.2019.0207

Asbtract ( )   HTML  

References | Related Articles | Metrics

Tilt photogrammetry technology has the characteristics of high precision and wide range, and it can realize high-performance data processing in complex scenes. In this paper, the technology of tilt photogrammetry is explained, the working principle and process of tilt photogrammetry are explained, and the application and advantages of tilt photogrammetry to generate real scene three-dimensional model in practical work are analyzed in combination with water conservancy engineering surveying and mapping project.