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31.
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A framework of region-based spatial relations for non-overlapping features and its application in object based image analysis 总被引:2,自引:0,他引:2
Yu Liu Qinghua Guo Maggi Kelly 《ISPRS Journal of Photogrammetry and Remote Sensing》2008,63(4):461-475
Object based image analysis (OBIA) is an approach increasingly used in classifying high spatial resolution remote sensing images. Object based image classifiers first segment an image into objects (or image segments), and then classify these objects based on their attributes and spatial relations. Numerous algorithms exist for the first step of the OBIA process, i.e. image segmentation. However, less research has been conducted on the object classification part of OBIA, in particular the spatial relations between objects that are commonly used to construct rules for classifying image objects and refining classification results. In this paper, we establish a context where objects are areal (not points or lines) and non-overlapping (we call this “single-valued” space), and propose a framework of binary spatial relations between segmented objects to aid in object classification. In this framework, scale-dependent “line-like objects” and “point-like objects” are identified from areal objects based on their shapes. Generally, disjoint and meet are the only two possible topological relations between two non-overlapping areal objects. However, a number of quasi- topological relations can be defined when the shapes of the objects involved are considered. Some of these relations are fuzzy and thus quantitatively defined. In addition, we define the concepts of line-like objects (e.g. roads) and point-like objects (e.g. wells), and develop the relations between two line-like objects or two point-like objects. For completeness, cardinal direction relations and distance relations are also introduced in the proposed context. Finally, we implement the framework to extract roads and moving vehicles from an aerial photo. The promising results suggest that our methods can be a valuable tool in defining rules for object based image analysis. 相似文献
33.
在城区化过程中,由于人口快速成长且集中,随之而来的建筑物、道路等不透水面密度增加,导致地下水补给减少及破坏水文循环。为了解土地利用方式改变对长期水文量影响,建立一个适宜的城区水循环模式是非常重要的。选定台湾台北的六馆抽水站集水区进行分析,模式参数经过敏感度分析、率定与验证。采用改变不同透水铺面设置比例的方案,评估其对径流量、入渗量、蒸发散量的改变。并分析设置不同比例屋顶雨水贮集系统对地表径流量及供水量的改变。所建立的城区水循环模式是评估土地利用改变造成水文量的改变的一个有效工具,并可提供决策者做为城区土地利用决策的参考。 相似文献
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利用基础测绘数据中房屋数据获取和编辑的方法,探讨1:10 000基础测绘数据中的建筑物在城市地理信息服务和建模中的应用以及目前基础测绘数据与城市建模数据间的差距. 相似文献
37.
抚顺矿区城市下压煤面积6km^2,煤炭储量23901.5万t。通过对矿区地质特征、煤储层特征分析.认为区内煤层气含量高(9.81~24.53m^3/t),煤层中大空隙多,透气性好,渗透率较高(0.24~3.60mD)。煤层直接顶板为厚100m左右的致密油页岩,底板为泥岩、凝灰岩,具有良好的封闭条件。根据矿区多年测试资料,采用容积法得出区内煤层气资源量为30.53亿m^3。综合开发煤层气资源符合东北老矿区的实际,其将为复苏东北重工业基地提供有效的洁净能源。 相似文献
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Patterns of crystallographic preferred orientation are referred to as texture. The specific subject of texture analysis is
the experimental determination and interpretation of the statistical distribution of orientations of crystals within a specimen
of polycrystalline material, which could be metals or rocks. The objective is to relate an observed pattern of preferred orientation
to its generating processes and vice versa. In geosciences, texture of minerals in rocks is used to infer constraints on their
tectono-metamorphic history. Since most physical properties of crystals, such as elastic moduli, the coefficients of thermal
expansion, or chemical resistance to etching depends on crystal symmetry and orientation, the presence of texture imparts
directional properties to the polycrystalline material.
A major issue of mathematical texture analysis is the resolution of the inverse problem to determine a reasonable orientation
density function on SO(3) from measured pole intensities on
, which relates to the inverse of the totally geodesic Radon transform. This communication introduces a wavelet approach into
mathematical texture analysis. Wavelets on the two-dimensional sphere
and on the rotational group SO(3) are discussed, and an algorithms for a wavelet decomposition on both domains following the
ideas of Ta-Hsin Li is given. The relationship of these wavelets on both domains with respect to the totally geodesic Radon
transform is investigated. In particular, it is shown that the Radon transform of these wavelets on SO(3) are again wavelets
on
. A novel algorithm for the inversion of experimental pole intensities to an orientation density function based on this relationship
is developed. 相似文献
40.
试论我国城市发展方针 总被引:6,自引:0,他引:6
在执行重重工业的发展战略和城乡分割体制的计划经济背景下,我国制定了“控制大城市规模,合理发展中等城市,积极发展小城市”的城市建设方针。但是分析表明,这一方针不能适应市场经济和对外开放形势的需要,也不符合我国人多地少、农村剩余劳动力多的国情,必须调整现有的城市发展方针,选择适宜的城市化发展道路。因此,本文就适度发展大中城市,提高城市现代化水平;加速乡村城市化,积极合理发展小城镇;以及根据不同地区的具体情况,因地制宜地指定城市化途径等方面作了探讨。 相似文献