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Table of Content

    22 December 2009, Volume 38 Issue 6
    学术论文
    3D building model reconstruction from multi-view aerial images and LiDAR data
    CHENG Liang 2, 2
    2009, 38(6):  0-501. 
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    An approach by integrating multi-view aerial imagery and LiDAR data is proposed for automatically reconstructing 3D building models with precise geometric position and details. It consists of three main steps: building boundary extraction, 3D boundary determination and 3D building model reconstruction. Two new algorithms are proposed: (1) a method on 3D building boundary determination by integrating multi-view 2D boundaries and LiDAR data; (2) an improved split-merge-shape algorithm based on LiDAR data. The results demonstrated that the complex buildings can be reconstructed well by the proposed approach; comparing the approach only using LiDAR data, the constructed 3D models have higher correctness and completeness and have more accurate geometric position.
    Research on GPS Pre-processing Method for Ionosphere-free Combination Data Using Wavelet
    2009, 38(6):  0-481. 
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    Monitoring Urban Subsidence Based on SAR Interferometric Point Target Analysis
    2009, 38(6):  0-501. 
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    The great potential of Synthetic Aperture Radar Interferometry (INSAR) on topography and deformation mapping has long been recognized. But repeat-pass INSAR usually cannot succeed due to the impacts of spatial decorrelation, temporal decorrelation and atmosphere heterogeneity, which greatly limit the practical applications of this technology. Interferometric Point Target Analysis (IPTA) is one of the latest developments in radar interferometric processing. It is achieved by analysis of the interferometric phases of some individual point targets, which are discrete and present temporarily stable backscattering characteristics, in long temporal series of interferometric SAR images. This paper analyzes the interferometric phase model of point targets, and then addresses two key issues within IPTA process. Firstly, a spatial searching method is proposed to unwrap the interferometric phase difference between two neighboring point targets. The height residual error and line deformation rate of each point target can then be calculated, when a global reference point with known height correction and deformation history is chosen. Secondly, a spatial-temporal filtering scheme is proposed to further separate the atmosphere phase and non-linear deformation phase from the residual interferometric phase. Finally, an experiment of the developed IPTA methodology is conducted over Suzhou urban area. Totally 38 ERS-1/2 SAR scenes are analyzed, and the deformation information over 3546 point targets in the time span of 1992~2002 are generated. The IPTA-derived deformation shows very good agreement with the published result, which demonstrates that the IPTA technique can be developed into an operational tool to map the ground subsidence over urban area.
    An Intelligent Model Supporting Traffic Connectivity Automation for City Road Networks
    2009, 38(6):  0-481. 
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    Fast Algorithm of Power Optimization for Polarimetric Random Mechanisms
    CHEN Qiang
    2009, 38(6):  0-501. 
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    Target optimal polarization state is the basis of the theory of radar polarimetry. Aiming at the large mount of calculation of the traditional algorithms for polarimetric power optimization of random target in arbitrary channel, a fast algorithm is proposed in this article. Firstly, the function of received power in arbitrary channel is unified as the form of copolar power. Then based on the change of polarimetric basis, the copolar power is analyzed theoretically to obtain the minimum interval of target optimal polarization state in plane, which provides theoretic support for anticipating its position. Finally the optimal polarization state is obtained by interval dichotomy. The experiment results of an actual polarimetric data show that the proposed algorithm can save the computation greatly and is more convenient to realize than the Lagrange multiplier method and the method of traversal search.
    Extracting Texture Features from Remotely Sensed Imagery with Fast Gabor Filters Implemented with Kernel Decomposing and Recursive Filtering ReplaceChar1('spanTitle');ReplaceChar('spanTitle');HanderTitle('enTitle','chTitle','enTitle');
    2009, 38(6):  0-481. 
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    A fast remotely sensed image texture feature extracting method is proposed. It firstly decomposes a 2-D Gabor filter along x,y axes into a set of 1-D filters,which avoids the precision and efficiency losing of re-sampling which is necessary when the decomposing is carried out along some inclined orientations of an image plane. Besides,a recursive method is implemented to further improve the efficiency of the decomposed 1-D filtering. A Gaussian filter is used to smooth the filtering outputs,which are then subjected to k-means clustering method for textural image segmentation. A comparison between the method and FFT-based Gabor filtering method is carried out. It demonstrates that our method is a feasible and fast way to extract texture features from remotely sensed imagery,for its higher algorithm efficiency and little precision losing. ReplaceFont('ChDivSummary','设计一种在x、y轴方向上进行2维Gabor滤波器模板分解的可行方法,从而避免模板分解时在倾斜方向上进行重采样所带来的效率、精度损失;接着采用递归方法实现分解后的1维滤波器以进一步提高算法效率。采用高斯滤波对Gabor滤波结果进行校正平滑作为纹理特征输出,并采用k-means算法对其进行聚类以验证方法在提取图像纹理区域时的有效性。和以快速傅里叶变换方式实现的Gabor纹理提取方法进行对比,实验表明,该方法在纹理特征提取上的精度损失很小,但在算法执行效率上则有显著的提高。');ReplaceFont('EnDivSummary','A fast remotely sensed image texture feature extracting method is proposed. It firstly decomposes a 2-D Gabor filter along x,y axes into a set of 1-D filters,which avoids the precision and efficiency losing of re-sampling which is necessary when the decomposing is carried out along some inclined orientations of an image plane. Besides,a recursive method is implemented to further improve the efficiency of the decomposed 1-D filtering. A Gaussian filter is used to smooth the filtering outputs,which are then subjected to k-means clustering method for textural image segmentation. A comparison between the method and FFT-based Gabor filtering method is carried out. It demonstrates that our method is a feasible and fast way to extract texture features from remotely sensed imagery,for its higher algorithm efficiency and little precision losing.');if(document.getElementById('ChDivSummary') != null && document.getElementById('ChDivSummary').innerHTML!=""){CutSpan('ChDivSummary',500);DisplaySpanDiv('ChDivSummary');ClearSummaryOnLoad('SummaryLinkChID','SummaryLinkEnID');} if(document.getElementById('EnDivSummary') != null && document.getElementById('EnDivSummary').innerHTML!=""){CutSpan('EnDivSummary',1000);DisplaySpanDiv('EnDivSummary');ClearSummaryOnLoad('SummaryLinkEnID','SummaryLinkChID');}ReplaceChar1('ChDivSummary');ReplaceChar('ChDivSummary');ReplaceChar1('EnDivSummary');ReplaceChar('EnDivSummary');
    The Subdivision of Partial Grid Based on Discrete Global Grid Systems ReplaceChar1('spanTitle');ReplaceChar('spanTitle');HanderTitle('enTitle','chTitle','enTitle');
    2009, 38(6):  0-481. 
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    The Model of Crustal Horizontal Movement Based on CGCS2000 Frame
    2009, 38(6):  0-481. 
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    Research on Index of Landuse Data Generalization Based on the Influence of Scale and Landscape Pattern
    2009, 38(6):  0-501. 
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    Abstract: This paper studies index system of land parcels generalization which is critical problem in landuse data generalization. The macro and micro indexes of landuse data generalization is probed considering the influence of scales and landscape patterns. The typical sample set of landuse data at different scale and is collected all over China. The macro and micro of control rules of landuse data generalization at different scales and patterns are gotten. Taking a county as an example, the methods for landuse data generalization proposed in the paper are proved to be reasonable.
    Researches on Evaluation for Quality of Active Geospatial Information Service
    2009, 38(6):  0-481. 
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    简讯
    ACTA GEODAETICA et CARTOGRAPHICA SINICA CONTENTS Vol.38 No.1~No.4
    2009, 38(6):  0-481. 
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    学术论文
    Research on the Methods of 3D Virtual City Construction based on CA model
    WANG Hai-Ying 2
    2009, 38(6):  0-501. 
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    This paper unifies the urban cellular automata and the virtual reality technology to generate a three-dimension (3D) virtual city which is composed of the diverse buildings along with time and space variation. To construct an urban CA model that is based on the structure of a cellular entities can produce a layout of the virtual city with the buildings and a group of data about cellular state which is based on time series. We use DEM and DOM data to generate real three-dimensional terrain, load the 3D city model into the virtual scene through the APIs, and lay the city buildings to the corresponding position in the 3D virtual scene with the cellular entity attribute information. The result shows that the method can generate three-dimensional virtual city which is based on the timing changes and posed by diversification buildings.
    A Spatial-query-driven Transformation between Metric Spatial Relations and Natural-Language Spatial Relations:Taking Regions as Example ReplaceChar1('spanTitle');ReplaceChar('spanTitle');HanderTitle('enTitle','chTitle','enTitle');
    2009, 38(6):  0-481. 
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    Lunar Geomorphy 3D Visualization Method
    2009, 38(6):  0-481. 
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    The Changes Accumulation Model for Streaming Map Data Transferring over Web
    2009, 38(6):  0-481. 
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    The streaming transfer method which makes data immediately available application during the progress of transfer becomes a welcome transfer way over Web. The progressive transmission of map data provides the users with a self-adaptive strategy to access remote data. It not only speeds up the Web transfer but also offers an efficient navigation guide in information acquisition. The key technology in this transmission is the efficient multiple representation of spatial data and pre-organization on server site. This paper aims at vector data offering a new multiple representation model called changes accumulation model,which considers the spatial representation from one scale to another scale as an accumulation of set of changes. The difference between two consecutive representations is recorded in a linear index and through gradually addition or subtraction realizes the progressive transmission. As an example,the progressive transmission of area feature based on changes accumulation model is investigated in the paper. The model is built by hierarchical decomposition of polygon into series of convex hulls or bounding rectangles and through component of the decomposed elements to accomplish the progressive transmission.
    Direct and Inverse Transformation of the Perspective Projection
    2009, 38(6):  0-501. 
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    All the satellite images are obtained dynamically. The image which obtained in fast exposal way has the projection characteristic of perspective projection. In this paper, we discuss the elevation images of satellite which is taken dynamically, establish its perspective projection, and also research its direct and inverse transformation and the arithmetic of the ground track coordinates, finally, give a computational case.