Table of Content

25 March 2017, Volume 0 Issue 3

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Quality Analysis of GNSS Data

LI Xiaoguang, CHENG Pengfei, CHENG Yingyan, WAN Jun

2017, 0(3):  1-4,8.  doi:10.13474/j.cnki.11-2246.2017.0071

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The GNSS carrier phase observation value is affected by noise and the receiver clock jump, the cycle slip test sequence changes over time.To construct robust and sensitive test of cycle slip, satellite data of different system quality need to be analyzed, and the multi-path effect and signal-to-noise ratio are important indexes of the quality about observation data. This paper focuses on the analysis of the multipath effect and the signal-to-noise ratio of GPS and BDS satellites data; and proposed a method of receiver clock jump detection, which uses the O-C about dual frequency phase observation value and performs clock jump detection by using the ionosphere free linear combination.

Two-position Alignment Method for Inertial Navigation System of Rail Tester

ZHANG Xinchun, CUI Ximin

2017, 0(3):  5-8.  doi:10.13474/j.cnki.11-2246.2017.0072

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In order to improve the alignment accuracy of inertial navigation system in rail tester, a two position alignment method for the inertial navigation system is proposed, which is using of u-turn mode, to achieve inertial navigation system accelerometer constant bias compensation. Select 0.1°/h FOG and 200 μg flexible quartz accelerometers making up inertial navigation system, and carry out a test. The results showed that the two position alignment method can effectively remove the orbital parameters detection error causing by inertial devices bias error. Continuous operation for 300 m, the railroad level detection accuracy is significantly improved.

Influence Analysis of Solid Tide on Vertical Crustal Deformation and Gravity Changes in the Three Gorges Area

LI Xingqiao, ZHANG Chuanyin, WANG Wei, YANG Yang, YIN Cai, KE Baogui

2017, 0(3):  9-12.  doi:10.13474/j.cnki.11-2246.2017.0073

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In this paper, using the method of IERS protocol and DE405 ephemeris file, based on the CORS station and gravity station located in the Three Gorges area, the vertical crustal deformation and gravity changes in Three Gorges area from 2011 to June 2015 tide every 2 hours are calculated, and the spring tide tide influence distribution on December 14, 2012 is calculated. The results indicated that the solid tide in Three Gorges area has very strong periodicity,the long period of half month and half year, the short period of one day and half day.There are 2 times spring tide in Three Gorges area before and after the end of the per lunar month, the middle of a month and month at the end of the spring tide range is about 1/4; the annual winter (lunar declination 28 or 36, about November,December and January) and summer (about May,June and July, the solar altitude angle is close to the maximum tide) large tidal range, the spring and autumn small tidal range. High maximum tidal geodetic height 0.346 m and neap high -0.190 m (reference epoch 2000.0); solid tide on gravity and the vertical deformation of heterogeneous, a maximum of 110 μGal, minimum -200 μGal. Regional solid tide is obvious strip distribution, solid tide of vertical deformation and gravity changes influence the increase or decrease in the opposite direction. The research results of this paper can be for CORS, gravity stations of solid tide effect analysis,which provide a reference for related studies of the local solid tide.

Rusting Recognition Algorithm for the Containment of the Nuclear Power Plant Based on Contour Directed Dilation

XU Yaming, SUN Xueyan, WANG Zhen, YU Shuang

2017, 0(3):  13-16.  doi:10.13474/j.cnki.11-2246.2017.0074

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For defective rusting on nuclear containment image, with lots of noise and interference similar in color, in this paper a rusting recognition algorithm of contour directed dilation is proposed. Using the characteristic yellowish orange color, extract basic rusting information through RGB multi-channel threshold segmentation. On the basis of rusting's annulus shape feature, the rusting by multi-direction according to contour's extension direction is divided. Contour fragment is dilated by the self-design eight-direction kernels in order to complement annulus rusting. The real rusting is recognized by roundness calculated according to contour moments. Experiments show that the algorithm can undo amounts of noise and interference similar in color so as to recognize and position the real rusting on the image.

An Organization Method of Vehicle-borne Massive Point Cloud Data Using Tile Indexing

XIE Hong, HU Xiaobin, GONG Xun

2017, 0(3):  17-21,79.  doi:10.13474/j.cnki.11-2246.2017.0075

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To improve the efficiency of visualization and processing for vehicle-borne mobile scanning point cloud data,combined with the global tile indexing, a novel organization and swapping approach is presented.Based on the spatial distribution analysis of concerning data,a novel mechanism is established to manage the massive data effectively,integrating the tile indexing and random sampling octree appropriately. The implemented experiments show it performs well in the process of data swapping,inquiring,dynamic updating for massive urban-block data,as well as the extended post-processing progress including segmentation,classification,et al.

Accuracy Evaluation and Improvement of Volunteer Geographic Information Based on Image Matching

MA Chao, SUN Qun, XU Qing, WANG Zhijian

2017, 0(3):  22-25.  doi:10.13474/j.cnki.11-2246.2017.0076

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Aiming at the question that it is difficult to evaluate the accuracy of the volunteer geographic information under no vector reference data condition, a road accuracy evaluation method based on imaging matching is proposed. Firstly, the road intersections between the image and the volunteer geographic information are extracted as control points, and the corresponding control points are matched,then, the root mean square error of the control points of the same name are taken as road accuracy of the volunteer geographic information; Secondly, Delaunay triangulation network are respectively built by two sets of the control points, and affine translation for each triangulation network are conducted by using the corresponding relationship between these two sets, in order to achieve geometric correction of volunteer geographic information and improve its accuracy. Finally, the road data of Open Street Map in Zhengzhou city are utilized to do an experiment. The result shows the algorithm proposed in this paper is able to improve the road accuracy of the volunteer information effectively.

Application of SBAS Technique in Surface Subsidence Monitoring of Nanjing Hexi Area

GUO Leping, YUE Jianping, YUE Shun

2017, 0(3):  26-28,41.  doi:10.13474/j.cnki.11-2246.2017.0077

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Due to the influence of geological conditions and the accelerating of urbanization progress,land subsidence of Hexi area, Nanjing has become increasingly obvious. In this paper 16 views Japan ALOS PALSAR satellite ascending orbital data from 2007 to 2011 are taken as an example. By using SBAS technology to analyze subsidence trend of Hexi area, the surface deformation field of study area was inversed. Compared with measurement data, the accuracy and timeliness of the SBAS for subsidence monitoring are verified.

Impact and Analysis of Shadow Area Extracting to the Terrain Radiation Correction for High Resolution Image

SONG Liyao, ZHANG Hao, LIN Feng

2017, 0(3):  29-33,66.  doi:10.13474/j.cnki.11-2246.2017.0078

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By using transporting mechanism to correct topographic radiation, we can fully consider direct solar radiance, sky diffuse radiance and near surface reflectance radiance, and get a better result. The key factor that determines topographic correction result is accurate extraction of shadow factor. The article use DEM method and histogram threshold segmentation method to compute shadow factor of the same area of SPOT-5 panchromatic imagery, and then use the same radiation transmission model to correct topographic radiation. By contrast, the result that using the histogram threshold method is better than DEM method when DEM accuracy is not high enough, and these have fully proved its value and advantage.

A Method of Aircraft Recognition in Remote Sensing Images

YIN Wenbin, WANG Chengbo, YUAN Cui, QIAO Yanyou

2017, 0(3):  34-37.  doi:10.13474/j.cnki.11-2246.2017.0079

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High resolution remote sensing images often has the characteristics of huge data amount, complex background and low ground objects proportion. It is inefficient to use RCNN model for object recognition in high resolution remote sensing images directly. The cascade AdaBoost has the advantages of high recall rate and fast calculating speed, while it is likely to detect more false targets. In this article, a coarse to fine aircraft recognition method is proposed by combining RCNN model with cascade AdaBoost. Firstly, a HOG based cascade AdaBoost is applied to extract the candidate aircraft regions quickly. Then we classify the candidate regions with the support vector machine (SVM) classifier using features computed from convolutional neural networks. The results show that this method can ensure the accuracy and improve the computational efficiency.

Study of the Evaluation Index System of the Smart City Spatiotemporal Information Cloud Platform

LIU Xiaoli, LI Chengming, YIN Jie

2017, 0(3):  38-41.  doi:10.13474/j.cnki.11-2246.2017.0080

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For defining evaluation of security level of urban intelligent capability and actual effect brought by the construction during the construction process of smart city spatiotemporal information cloud platform as well as providing the basis for development smart city, this paper has researched and proposed overall framework of evaluation index system and evaluative factors for constructing smart city spatiotemporal information cloud platform construction as well as conducted marking tests in pilot cities according to state smart city evaluation index system and its requirements of setting up sector evaluation index. Index has also been revised and perfected in accordance with the test results, so as to guide and promote cities to construction smart city spatiotemporal information cloud platform in a targeted, planned and methodical way.

Research on Fast Development of 3D Lunar Topography Representation Platform Based on Mobile Devices

ZENG Xingguo, ZUO Wei, MU Lingli, ZHANG Zhoubin, LI Chunlai

2017, 0(3):  42-45.  doi:10.13474/j.cnki.11-2246.2017.0081

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Restricted by the computing capability of the smart mobile devices and the speed for 3D map data transmission through mobile internet, how to display the 3D lunar map on mobile devices smoothly and represent the lunar topography in detail is still a problem. To solve this problem,the state of art for mobile 3D map was investigated, and based on the work, an asynchronous rendering strategy for 3D Lunar Mapping on mobile devices was proposed. With the method and Chang'E lunar data, a 3D lunar map prototype system for mobile devices was developed and successfully implemented in the program for Chang'E lunar topographic data release.

Scale Selecting of Geographic National Conditions Information Statistical Grids with Spatial Autocorrelation——A Case Study of Vegetation Cover Information Statistics

LIAN Shizhong, DING Lin, CHEN Jiangping

2017, 0(3):  46-51,90.  doi:10.13474/j.cnki.11-2246.2017.0082

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The difference in statistical grid scales will bring different statistical results, so it is important to select statistical grids for the geographical conditions information statistics. A method of choosing statistical grids scale of geographical conditions information with spatial autocorrelation being taken into account is proposed. By using geographic conditions census data and taking vegetation cover information statistics as an example, the study gets vegetation cover girds data, under the rule of maximum area and the rule of centric cell in scales of 50 m, 60 m, 70 m, 80 m, 90 m, 100 m, 250 m, 500 m and 1000 m, and meanwhile calculates vegetation cover statistical errors, analyzes changes of spatial autocorrelation of vegetation cover gird data at different scales to make scale selection, and then uses vegetation cover statistical errors to obtain an appropriate statistical grid scale of vegetation cover information statistics. The results show that for vegetation cover information statistics of geographic national conditions, the suitable scale is 250 m in areas with high degree of vegetation coverage, and 100 m in areas with low degree of vegetation coverage.

A Road Plane Geometry Analytical Model Based on Mileage Parameter

TAO Lu, ZHU Dunyao, WANG Junde, ZHANG Pan

2017, 0(3):  52-57,90.  doi:10.13474/j.cnki.11-2246.2017.0083

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With the development of active safety technology and autonomous driving technology, high precision map has been used in many applications. A road geometry analytical model based on mileage parameter was proposed for high precision map. By constructing the orthogonal polynomials based on the data set and using restricted least-square method, the geometric description parameters were dynamically calculated based on maximum fitting error. The model can precisely describe the road geometry, and minimize the data redundancy. It can also ensure the continuity and smoothness of the road geometry. The model was used for high precision map production of 120 km highway. Taking three typical roads as examples, the advantages of proposed model were validated.

Technology of Topographic Map Updating Based on Map Information Volume

MO Zhongxia, ZHANG Xinchang, HE Xianjin

2017, 0(3):  58-61.  doi:10.13474/j.cnki.11-2246.2017.0084

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With the rapid development of urban construction, the management of vector topographic map data and automatic updating have been attached great importance to the land planning department. On one hand, the region-based updating method is easy to implement and of high efficiency, but it may cause the redundancy of historical database because of repeated updating of non-changing elements. On the other hand, the element-based updating method which is not suitable for large changes in the amount of updates because it merely updates the changed elements and needs complex change detections. In order to solve the problem that the updating method cannot be adaptively selected during the process of updating, a map updating method based on map information variation is proposed. Based on the updating cases of 1:2000 topographic maps of residential areas, we found that the proposed method can effectively improve the data updating efficiency. We can also draw the following three conclusions. ① When the rate of change is less than 20%, the element-based updating method is adopted. ② If the rate of change is more than 55%, the region-based updating method can produce higher update efficiency. ③ The update efficiency is not significant when the rate is between 20% and 55%. The experimental results have important reference value for the design of the updating scheme of topographic maps.

A Method for Location-based Information Sharing Based on WiFi Direct

WANG Bingbing, CHEN Gang, ZHANG Jinming

2017, 0(3):  62-66.  doi:10.13474/j.cnki.11-2246.2017.0085

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It is difficult for devices to share location-based information with each other, when they are off-line. A method that builds and tests wireless ad hoc networks for Android devices based on WiFi Direct is tried, by which we implement the location-based information sharing, as well as we take the situation in which some devices in the group have a connection to the server into consideration. The test shows that the method could be a solution to the problem that devices can't share location-based information with each other or request information from the server to some extent, which is caused by network interruption.

Accuracy Analysis for Single Beam Echosounder Interpolations

CHEN Changbo, LIU Xiaoding, ZHU Ziyang, ZHOU Kun

2017, 0(3):  67-70.  doi:10.13474/j.cnki.11-2246.2017.0086

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In the paper the accuracy for single beam echosounder interpolations using error propagation law is analyzed. A mathematical model of medium error expression for interpolation of water depth in single beam is established and the results in three experimental zones of a coastal zone in south China is tested. The inverse distance weighting method, shepard method and linear interpolation triangulation method with adaptive Search Radius Method are used to compute the gross error of water depth interpolations in this test. The results show that the ratio of gross errors is less than 5% and the three methods are superior in efficiency and quality. Also, we get that the interpolations' accuracy is related to the precision of data source, but not to the density of data source. In the case of a given depth measurement limit error, we suggest that the limit value of Grid point water depth value should set to be 0.4m in the digital water depth model standards.

Topographic Mapping Using 3D Laser Scanning Technology Integrated with RTK

WANG Feng

2017, 0(3):  71-75.  doi:10.13474/j.cnki.11-2246.2017.0087

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Due to target scanning and total station aided measuring, the process becomes so complex. Therefore, the topographic mapping solution using 3D laser scanning technology integrated with RTK is introduced in this paper. The position of scanning position is measured synchronously by coaxial network-RTK; two level registration strategies are including coarse registration by corresponding points and ICP registration by polygon search; the peripheral RTK points of survey block is utilized to absolute orientation; the platform is developed for topographic mapping. Topographic Mapping Experiment was made with typical features terrain, the scanning efficiency is improved by about 5 times, and the working efficiency is improved by about 3 times by comparing with traditional digital mapping.

Realization of Mapping System Integrated Both Up-water and Under-water with Multi-sensor Integration and Data Fusion

CHEN Ke, WANG Chong, WEN Ping, WU Jie, GUI Lin

2017, 0(3):  76-79.  doi:10.13474/j.cnki.11-2246.2017.0088

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The mapping system integrated both up-water and under-water provides an efficient and rapid solution for water-related survey works. The study background on multi-sensor integration and data fusion was presented firstly. The primary theory and methodology of mapping system integrated both up-water and under-water was stated detailedly. Based on project test data, the accuracy statistics and analysis on point cloud data were worked out precisely. It was demonstrated that the proposed integrated mapping system would be an efficient solution and could satisfy the specification requirement of water conservancy and hydropower engineering project applications.

Method Research of Vehicle-borne Mobile Surveying Technology in Large-scale Topographic Mapping

WU Bo, YANG Xiaofeng, CHEN Hongqiang, LI Jun, HOU Xingze

2017, 0(3):  80-82,107.  doi:10.13474/j.cnki.11-2246.2017.0089

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Combining the technology of vehicle-borne mobile surveying with surveying area's practical situation, the process for filed scanning and data processing are researched. Then the method of inspection and producing of large-scale topographic map by using point cloud and image is expounded in detail. After that, this paper contrastes the vehicle-borne mobile surveying technology with the traditional ways. Result shows that the vehicle-borne mobile surveying technology can satisfy the accuracy of surveying and mapping of 1:1000 topography map, and the topographic map production will be more efficient by using it. This paper will provide some reference for the application of vehicle-borne mobile surveying technology in large-scale topographic mapping.

A Modeling Technical Scheme Based on 3D Laser Point Cloud

SHI Shaowei, LI Yufu, WANG Ruizhong, LI Zhikuan, HOU Shaocong, LI Yan, JIN Zhenshi

2017, 0(3):  83-85.  doi:10.13474/j.cnki.11-2246.2017.0090

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With the development of digital city construction, large-scale buildings need to build 3D models. The traditional method of total station is very difficult, especially for the complex modeling construction, coal plant, refinery equipments and so on. In this paper, a 3D modeling method of 3D laser point cloud data is proposed, which can greatly shorten the time of data collection and reduce the workload.

Using Micro-UAVs for the Land Consolidation and Rehabilitation Projects Supervision

XU Xiuyun, CHEN Xiang, LIU Baomei

2017, 0(3):  86-90.  doi:10.13474/j.cnki.11-2246.2017.0091

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Combining the demand,application status and development trend for land consolidation and rehabilitation projects supervision in Land Consolidation Center, Ministry of Land and Resources,this paper analyzed the adaptability of the use of micro-UAVs in supervising on land consolidation and rehabilitation projects,and shared it's procedures,methods of the application in land consolidation and rehabilitation projects supervision and problems discovered in remote sensing monitoring,then gave suggestions on improving and promoting the management methods and supervision approachs of land consolidation and rehabilitation projects by using micro-UAVs.

The Updating Methods of the 1: 2000 Topographic Map Database for Cities Based on Feature and Area

GAN Zongping, DENG Shaoping, FANG Jun, LI Chaokui

2017, 0(3):  91-95.  doi:10.13474/j.cnki.11-2246.2017.0092

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Updating of the large-scale topographic map database is an important long-term task.The difficulty of rapid updating of 1:2000 topographic map database is analyzed, a semi-automatic and rapid updating method of large scale topographic map database combining aerial photography, satellite remote sensing, area updating and feature updating is proposed. The changed areas and features are extracted from the satellite images before and after the update by using the change detection method. Then the area-oriented and feature-oriented methods are used to measure the changes from high-resolution aerial images. Finally, semi-automatic spatial entity matching method is used to establish the backtracking association between the status database and the historical database, so as to realize semi-automatic and incremental updating of the topographic database. The method was used to update the 1:2000 topographic map of the eastern area of Zhongshan. The experimental results show that the method of updating the urban large-scale topographic map database using the feature and the area pattern with the satellite image has improved the efficiency by 25% compared with the traditional method.

An Architecture of Public Sentiment Monitoring Based on Geospatial Big Data

YANG Zongliang, ZHANG Yuqian, LI Jianfei

2017, 0(3):  96-100.  doi:10.13474/j.cnki.11-2246.2017.0093

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Several popular software of Internet public sentiment monitoring were compared and their advantages and shortcomings were comprehensively analyzed. A software architecture for Internet public sentiment monitoring based on geospatial big data was proposed. It has been tested with data acquisition, data processing, visualization of thematic networks with public sentiment, geospatial thematic map on public sentiment, geospatial spatio-temporal correlation analysis and other functions. The research has been applied to the actual project. The reslut improved the efficiency of the public sentiment monitoring system. It can be effectively used to monitor network hot events and to make a scientific decision.

A Method of Spatial Data Edge Matching and Storage

LIU Shanlei, WANG Shengyao, SHI Shanqiu, ZHANG Rui

2017, 0(3):  101-103,107.  doi:10.13474/j.cnki.11-2246.2017.0094

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In this paper, a new method of spatial data edge matching and storage is proposed to improve the low efficiency and uncontrollable quality of traditional methods.For increasing the extraction efficiency of elements which should be merged on both sides, the optimum segment of the matching line has been processed according to the total number of elements and the length.At the same time, in order to meet the quality requirements, the network analysis technology has been used to optimize the data and delete the redundant nodes.The practice shows that the proposed method can take the efficiency and quality of spatial data edge matching and storage into account, and save labor, expenses and time. It has played an important role in basic surveying and geography census.

Research on Cross-scale Linkage Updating Rules of Fundamental Geographic Information

DU Xiao, LIU Jianjun, YANG Mei, LIU Jianwei, ZHAO Wenhao, LI Zhao

2017, 0(3):  104-107.  doi:10.13474/j.cnki.11-2246.2017.0095

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This article introduces the rule architecture of key technology in the linkage updating of fundamental geographic information, describes the layer mapping, geometry correspondence, map synthesis, feature selection and spatial relationship coordination, et al, which can realize accurate extraction of change information. Research on constraint rules based on incremental element editing and automatic annotation are also carried out, and does the cross scale based geographic information linkage updating test with 1:10 000 DLG data linkage updating of 1:50 000 DLG data as an example.

Research on Major Project for Surveying, Mapping and Geoinformation Development during the 13th Five-Year Plan Period

RUAN Yuzhou, JIA Dan, XIONG Wei, LIU Fang

2017, 0(3):  108-110,127.  doi:10.13474/j.cnki.11-2246.2017.0096

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The implementation and effects of major project for Surveying,mapping and geoinformation in earlier stage are summarized.Service demand from various aspects of economic society is analysed. Thinking for distributing major project for surveying, mapping and geoinformation during the 13th Five-Year Plan period is presented. And a shipment of major project are condensed, so as to help project management and decision for surveying, mapping and geoinformation.

Design and Application of Quality Information Management in Surveying and Mapping

LIU Manli, CHENG Lijun, XIAO Qian

2017, 0(3):  111-113,123.  doi:10.13474/j.cnki.11-2246.2017.0097

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According to the analysis of the status of the quality information management in surveying and mapping quality inspection business, the design of provincial and national quality information management is put forward in this paper. And through the integration of provincial and national quality information management, the interoperability and unified management of quality information across the country are achieved, so as to provide a way for the quality information management of the information quality inspection.

Research on the Key Technology of a Station Management Platform for Surveying and Mapping Data Archives Information

GUO Haiqing, HUO Liang, CHENG Hongyu, YANG Yaodong, ZHU Wangzhang

2017, 0(3):  114-119.  doi:10.13474/j.cnki.11-2246.2017.0098

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Based on the research of existing surveying and mapping data management methods, a station management scheme of surveying and mapping data archives information is designed according to the requirements of informatization surveying and mapping, and a station management platform for surveying and mapping data archives information is realized. Practice has proved that the program can meet the needs of different departments of surveying and mapping data management, improve data management efficiency and also provide users with more convenient surveying and mapping data services.

A Method of Converting DEM into Contours Based on Slope Division Filtering

ZHAO Xuesong, WU Junfeng

2017, 0(3):  120-123.  doi:10.13474/j.cnki.11-2246.2017.0099

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While converting DEM into contours, the existing methods are incapable to find a good balance between curve smoothness and the loss of topographic accuracy. Thus, the authors thought of the method of converting DEM into contours based on slope division filtering. This method uses different-sized windows to average filter the slope division and control the filtering elevation difference, which better balances the curve smoothness and the loss of topographic accuracy and meanwhile automatically recognizes, interrupts and deletes the narrow intermediate contours between the index contours. The authors made use of the ArcGIS+Python script to develop a tool which could automatically convert DEM into contours. The tool was applied in contours collecting in the program of Digital Guangxi Geo Spatial Framework Construction and had got good results.

A Map Matching Algorithm Based on Meshing and Direction Weighting

LIAO Jia, YU Jianzhong, LI Junfeng

2017, 0(3):  124-127.  doi:10.13474/j.cnki.11-2246.2017.0100

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Map-matching algorithm is to correct the point that deviated from the road to the correct location. The candidate matching road is confired through leading the concept of grid division and the degree of matching about a point to a line is calculated through weighting factors of the direction based on traditional point-to-line map-matching algorithm. The test shows that the improved algorithm can improve the accuracy of the algorithm and the efficiency of the algorithm to a certain extent. This Algorithm has some practical value.

Further Development for AutoDesk Map in Topographic Mapping

GAO Xing'anm, HAO Wenguang, WANG Jiaolong

2017, 0(3):  128-129,136.  doi:10.13474/j.cnki.11-2246.2017.0101

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In the actual production, there is the need to make the topographic map of CAD format by using GIS data, but the loss of attribute information of the traditional conversion method is serious, which brings inconvenience to the later mapping work. Using AutoDesk Map to make format conversion can greatly reduce the loss of attribute information. On the basis of better preservation of attribute information, to a certain extent, the further development of the software can improve the degree of automation of mapping.

Application of Leveling Electric Handbook on Android for Practical Teaching

YUAN Debao, YANG Chunyu, CHEN Yaohui, JIANG Jinbao, SUN Wenbin

2017, 0(3):  130-132.  doi:10.13474/j.cnki.11-2246.2017.0102

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In traditional leveling survey, we usually use the traditional paper to record and calculate data. But it is easy to get wrong and has major limitations. The practice of applying electronic handbook to leveling teaching can break the bottleneck. The paper shows how we designed the electronic handbook using Java language by studying the leveling requirements. The electronic handbook can be easily used on the mobile end and tablet PC. By this way, the measurement efficiency improved greatly and reduced the calculation error in the process of observation. Finally, we took a mining area of leveling data to prove its effect.

Practice on the Diversified Training Mode of Excellent Engineer for Surveying and Mapping Speciality

CHEN Guoliang, WANG Yunjia, ZHANG Shubi, DENG Kazhong, YANG Huachao

2017, 0(3):  133-136.  doi:10.13474/j.cnki.11-2246.2017.0103

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"Education and Training Program for Excellent Engineers of Surveying and Mapping" is an important task of strategic importance in the reform and development of higher education in the "National Medium and Long-term Educational Reform and Development Plan". In this paper, grasping the key elements of talent training mode innovation as breakthrough point, we innovate a set of industry-oriented surveying and mapping engineering professional talents training system, build up the talent cultivation mode of "high engineering quality and strong practical ability", improve the professional course system, strengthen the construction of teachers, strengthening the multi-practice teaching, construct innovative practice platform, and focus on improving the students' engineering awareness, engineering quality and engineering practice ability.

Reforming of the Practice Teaching in the Course of Microwave Remote Sensing Assisted by Open Source Software

WANG Zhiyong

2017, 0(3):  137-140.  doi:10.13474/j.cnki.11-2246.2017.0104

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In view of the problems existing in the teaching of microwave remote sensing, such as the lack of practical ability and the lack of data processing ability training, we reformed the practical teaching for the course of the microwave remote sensing assisted by open source software. Firstly, it analyzed the advantages and disadvantages of open source software in experimental teaching. Then, it introduced the open source software and their main functions in the course of the microwave remote sensing. Then, a set of practical teaching projects of microwave remote sensing assisted by open source software were constructed. The standard experimental data set were established and the guidebook materials for the experiments were compiled. The experimental data and materials were shared through the network, such as the Baidu cloud disk and other ways. Through the teaching reform, it can extend the ways to practical teaching for the students. And it can improve the students' practical ability and data processing ability for the microwave remote sensing.

Research on the Training Mode of GIS Specialty Considering the Characteristics of the School and the Abilities of Students-Taking the GIS Specialty of Beijing University of Civil Engineering and Architecture as an Example

ZHANG Xuedong, WANG Yong, PANG Lei, HE Shuguang

2017, 0(3):  141-144,148.  doi:10.13474/j.cnki.11-2246.2017.0105

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With the rapid development of geographic information science (GIS) expertise, the technology has been applied to all aspects of society, so that people's production and life has undergone tremendous changes, a lot of industries and research fields began to use GIS to solve the practical problems of scientific research, production,economic and social development. Faced with the current social needs of multi-level applications, there is the urgent need for a large number inter-disciplinary talents of both master GIS technology, who also understand the management, and the ability to deepen the application of GIS technology. However, relative new characteristics of social demand, college graduates GIS professional training of our country is facing many limitations and shortcomings, it is difficult to meet the needs of society. This requires reform existing GIS professional training mode of university, from the social multi-level needs, combined with the objective reality of the current social development, set up a GIS Professional Training Model of highlighting school characteristics and student ability.

Thinking about the Teaching Reform of Engineering Surveying under Background of MOOC

GUO Bing, SUN Xiaorong, WU Jie

2017, 0(3):  145-148.  doi:10.13474/j.cnki.11-2246.2017.0106

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"MOOC", as a new form of open online course, has brought about a new reform of teaching philosophy and teaching models. Based on MOOC theories, this paper analyzes the current teaching situation of engineering surveying course. In view of existing problems in the current teaching, it explores reform mentality of teaching, establishes MOOC-oriented composition system of engineering surveying course, and designs a flipped-class teaching mode.