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Psychological suggestion is an educational approach that exerts influnce on the educated people's psychology and behavior in teaching. This paper analyzes the problems that exist in GIS teaching, such as difficult understanded teaching contents, poor interactive teaching, dry class atmosphere, and takes the cartography knowledge as the breakthrough point and applys the positive psychological suggestion...
It is well known that a minimum of four GPS satellites is required to obtain a 3D position fix. However, due to the obstructions, satellites visibility can become very low in certain areas. In recent years, newly acquired LiDAR Digital Elevation Models (DEMs) at 1m or even higher resolution have become more accessible and thus can be used to aid GPS navigation. The interpolated height from a highly...
With the development of informationization in our country, it becomes very imperative to informationize in the field of historical relics management. Historical relics have the great value in history science and art. In order to improve the ways and means of the survey and management of cultural relics, this paper discusses the Construction of Immovable Historical Relics Survey and Management Information...
InSAR (Synthetic Aperture Radar Interferometry) and D-InSAR technique is a more speedy deveolpping microwave remote sensing technique in recent years. The key problem that makes use of an InSAR data to carry on monitoring surface is: the biggest deformation monitor gradient of object is bigger than the biggest deformation gradient that InSAR can monitor, result in a serious decoherence phenomemon,...
The measurements in geospatial surveys always contain random errors. In this paper, the Total Least Squares (TLS) method, which accounts for the errors both in the observation vector and design matrix, is applied in the triangulation geospatial surveying adjustment. Two frequently used TLS algorithms, which are the singular value decomposition (SVD) based TLS algorithm and the iterative TLS algorithm...
Sobol algorithm is one of the most representative global sensitivity analysis methods. Parameters sensitivity analysis is a necessary step for crop model localization and regionalization. We used Sobol algorithm to analyze the parameters sensitivity of ALMANAC model, including crop parameters, soil parameters, meteorological parameters and field operating parameters. The result of the study showed...
Terrain visibility analysis is widely used in many areas, but the existing methods still have some unsolved problems, such as complexity in computation and bad applicability. In this paper, a depth mapping based method is given to solve the problem. First, the terrain was rendered with perspective projection from the observation point, and the depth of the terrain surface was saved into a depth map...
Crop planting area is significant to agricultural structure adjustment and regional food balance policy. Based on field investigation and spectral property analysis of corn in HJ1-CCD images, different threshold configurations are set to build decision trees and corn planting area is precisely extracted utilizing multi-temporal HJ-1 CCD images in Zhecheng county, Henan Province of China. Both statistical...
Lacking of ability for managing and analyzing Ecology data, the currently available reservoir information system can not satisfy the demand of ecological operation. Based on the analysis of ecological environment and its influencing factors, this paper organizes and classifies the reservoir information, and builds the relationship between multiple data with contrastive analysis methods. A reservoir...
Guam, USA has been facing drastic landscape change since World War II, especially when President John F. Kennedy lifted the Naval Clearing Act which opened Guam's ports to domestic and foreign visitors in 1962. Extensive construction activities in 1970s and 1980s changed the land cover in Guam, particularly the central and northern parts of Guam a lot. This research is focused on determination of...
This paper presents a method that apply shape context features to identify building from high remote sensing image automatically. This method use adaptive algorithm of key point detection to detect the key point of building boundary rapidly. By eliminating the unstable points, the stability of detected edge points can be improved. We apply the selected points for log-polar coordinate's transformation...
The Liaodong Bay is the northernmost part of China's seas, and sea ices are often seen there in cold winter, which strongly affect the development of marine economy, maritime transportation, and offshore fishery. The temporal and spatial changing patterns of sea ices in the Liaodong Bay were primarily examined with Landsat remote sensing images totaling 20 scenes. The results show that sea ices in...
Clouds are integral part in 3D-GIS visualization, without them 3D scene seem unrealistic. The paper presents a technical framework to simulate clouds from macroscopic to microcosmic scale in Global 3D-GIS. In the case of the macroscopic scale, which means the viewpoint is far away from the 3D scene in 3D-GIS, cloud was expressed with semi-transparent planar texture. In other case, we consider the...
Land use/cover change which is one of the most sensitive indicators that echo the interactions between human activities and natural environment, has become a core issue in the global environmental change and sustainable development disciplines. In this study, we applied temporal trajectory analysis method to detect land use/cover changes in Baishan city. The available satellite imageries are Landsat...
Make full use of the characteristics of GIS spatial data, according to the actual situation of the shortest path between any two Distribution Points, achieve optimal path selection in GIS platform. In this paper, MapInfo software as the design platform and MapBasic as the development of language, the system design has modules: User management module, the delivery information management module, the...
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