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1.
魏为兴 《福建地质》2013,32(1):44-51
三维地理信息技术是目前GIS科学发展的新趋势之一.它以三维虚拟可视化技术给用户展现地理空间现象,不仅能表达空间对象间的平面关系,而且能描述和表达他们之间的立体关系.3D GIS平台仿真展示地形(地貌)、地质体的三维场景,地质三维可视化应用,能便于地学工作者深入分析地质体的空间展布规律,尤其是通过视点的变化,拓宽观察地质体空间展布的视野.  相似文献   

2.
大规模地上、地下三维实体建模与空间分析应用中,由于三维模型的多样性和对象空间分布的不均衡性,如何高效地一体化组织和管理海量三维空间数据成为当前三维GIS的核心问题之一.提出了一种兼顾空间关系与语义关系的三维空间数据库模型,给出了相应的概念模型、逻辑模型和物理模型.特别针对地质体的复杂性,给出了顾及语义的多尺度地下空间目标概念模型和多层次三维空间索引机制.用武汉市和南京市三维数字城市示范区模型数据进行了应用试验分析,验证了该模型的有效性.   相似文献   

3.
一种面向对象的三维地下空间矢量数据模型   总被引:1,自引:0,他引:1  
针对地下空间的真三维连续特性以及建模过程的动态交互编辑与分析要求,提出了一种新的三维地下空间矢量数据模型。该模型采用面向对象思想对地下各种空间对象进行抽象描述;利用模型中的线段要素增强几何元素之间拓扑连接关系的维持,为地质体的切割和地下工程体的开挖等分析提供了算法上的便利;引入拓扑面更好地表达了地下空间对象之间的拓扑邻接关系。该模型在三维地下空间数据的存储管理、查询分析以及实时逼真绘制等方面都表现出较好的性能,适用于地下勘探工程的建模与分析。  相似文献   

4.
在GIS技术环境下开展资源定量评价, 实现资源评价工作的自动化、数字化、智能化是矿产资源勘查与预测的重要发展趋势.为了给地质勘查与预测人员、定量建模人员、GIS分析与操作人员提供共同研究和技术讨论平台, 提出了在矿产资源预测全过程使用的建模技术.介绍了建模技术的基本概念、空间模型建立、图形建模技术以及建模技术在矿产资源定量预测中的应用, 介绍了GeoDAS GIS中的建模技术基本功能以及建模技术在空间对象相关分析、证据(信息) 图层提取、不规则地质单元划分、预测后验概率绘制等矿产资源预测工作中的应用实例.应用结果表明, 建模技术为地质预测人员、定量建模人员、GIS操作人员开展综合研究和空间决策提供了公共的平台, 有助于实现模型的共享和操作过程的自动化.   相似文献   

5.
成矿环境空间结构的模糊建模   总被引:3,自引:0,他引:3  
张振飞  夏庆霖 《地球科学》2005,30(1):109-113
为了提高矿产预测的精度和可靠性, 必须分析和利用与矿床有关的空间结构信息.提出了一种用模糊集建立成矿环境空间结构模型的方法.成矿环境空间结构是地质变量在矿床周围的分布, 可用变量与空间点之间的模糊关系来描述.同一地区的同类矿床, 其空间结构具有一定相似性, 通过这种相似性的极大化可对结构模型进行优化.优化的结构模型是一种包含了方向和距离关系的特殊的空间关联规则集, 也是模糊推理矿产预测的推理规则库.通过模糊推理进行结构相似性的比较, 可对任意点上的找矿有利性进行预测.以云南东川地区铜矿预测的实例说明了该方法具有良好的应用效果.   相似文献   

6.
通过对目标知识库、目标数据库、地理信息系统(GIS)、形状分析和模式识别等技术的研究,提出了一种基于知识的目标识别方法.该方法提取目标遥感图像的空间特征和光谱特征,结合GIS空间分析功能,根据知识库中的先验知识进行推理,实现了典型目标的判别和提取.  相似文献   

7.
李振华 《地球科学》2002,27(3):333-337
传统的关系数据库在GIS的应用中主要存在以下问题: 除数据类型简单, 不能很好地表达非结构化数据外, 也难以表示GIS中具有复杂结构的数据; 关系模型简单, 不能表达数据之间的层次, 继承、聚合、泛化或特化等在GIS广泛使用的关系; 与数据操纵语言如SQL和通用程序设计语言, 特别是目前流行的面向对象设计语言之间失配.采用面向对象技术可以较好地解决上述问题.ORACLE的空间数据库在传统的关系数据库上进行了面向对象的扩展, 即所谓对象-关系模式, 其核心在于增加了名为SDO-GEOMETRY的对象数据类型, 用于存储几何实体.ORACLE的空间数据库的应用示例表明: 以面向对象的形式表示空间数据比之于关系数据库中存放大量无意义的坐标有着很大的优势, 同时, 它在复合对象的表达方面, 在对于空间关系的处理方面都非常有效   相似文献   

8.
面向对象的GIS水文水资源数据模型设计与实现   总被引:15,自引:0,他引:15       下载免费PDF全文
分析和总结了地理信息系统(GIS)在水文水资源应用中存在的问题与挑战。在ArcHydro数据模型框架的基础上,对面向对象的GIS水文水资源数据模型的结构与实现进行了深入研究与探讨。面向对象的GIS水文水资源数据模型能够很好地表达水文对象的空间位置、特征属性、时间属性以及对象间的拓扑关系,能完整地描述水文现象在地理空间的运动过程,并在江西省中部清丰山流域地理信息系统建设中应用。应用结果表明,面向对象的GIS水文水资源数据模型为设计水文空间数据库提供了一个通用的结构框架,有助于推动GIS在水文学研究与水资源管理的深入应用。  相似文献   

9.
三维地质模型构建方法的研究及应用   总被引:25,自引:3,他引:22  
地质体三维建模是地学信息系统的核心问题之一.对三维GIS及地学领域的空间构模方法的现状进行分析,结合地质体工程特点,提出一种三维地学空间构模方法--似三棱柱(STP)法.该方法以似三棱柱体作为三维地质体建模的基本体元,并采用5类基本元素和6组拓扑关系对似三棱柱体的数据结构进行描述.它能有效地表达各种三维地质现象,也可以更好地与传统的多层TIN模型结合,维护好空间实体的拓扑关系.基于本文的建模方法开发了一个适合地质领域的三维GIS初步原型,并用实际钻孔数据进行了验证.  相似文献   

10.
徐世武  刘秀珍 《地球科学》2010,35(3):338-344
为了突破面向业务系统及面向问题的建模技术,提高地理信息系统(geographic information system,GIS)应用系统适应需求不断变化及复用的能力,采用工作流技术结合形式语言实现应用模型精确定量数学化的有效转换,利用重载方式对空间算子的抽象与扩展来简化异构大型分析建模与应用系统构建中逻辑模型过于繁琐复杂的技术,实现空间分析建模的可视化、精确化和简单化.在此基础上,结合可视化界面搭建、功能仓库和空间资源管理,实现支持跨GIS平台的应用系统快速构建集成环境,为多领域应用系统的集成及功能复用提供手段,降低GIS应用系统的开发难度,为GIS应用不断深入和全面推广提供技术支撑.   相似文献   

11.
Spatial ability is required by practitioners and students of structural geology and so, considering spatial skills in the context of cognitive science has the potential to improve structural geology teaching and practice. Spatial thinking skills may be organized using three dichotomies, which can be linked to structural geology practice. First, a distinction is made between separating (attending to part of a whole) and combining (linking together aspects of the whole). While everyone has a basic ability to separate and combine, experts attend to differences guided by experiences of rock properties in context. Second, a distinction is made between seeing the relations among multiple objects as separate items or the relations within a single object with multiple parts. Experts can flexibly consider relations among or between objects to optimally reason about different types of spatial problems. Third, a distinction is made between reasoning about stationary and moving objects. Experts recognize static configurations that encode a movement history, and create mental models of the processes that led to the static state. The observations and inferences made by a geologist leading a field trip are compared with the corresponding observations and inferences made by a cognitive psychologist interested in spatial learning. The presented framework provides a vocabulary for discussing spatial skills both within and between the fields of structural geology and cognitive psychology.  相似文献   

12.
Development of a 3D GIS and its application to karst areas   总被引:1,自引:0,他引:1  
There is a growing interest in modeling and analyzing karst phenomena in three dimensions. This paper integrates geology, groundwater hydrology, geographic information system (GIS), database management system (DBMS), visualization and data mining to study karst features in Huaibei, China. The 3D geo-objects retrieved from the karst area are analyzed and mapped into different abstract levels. The spatial relationships among the objects are constructed by a dual-linker. The shapes of the 3D objects and the topological models with attributes are stored and maintained in the DBMS. Spatial analysis was then used to integrate the data in the DBMS and the 3D model to form a virtual reality (VR) to provide analytical functions such as distribution analysis, correlation query, and probability assessment. The research successfully implements 3D modeling and analyses in the karst area, and meanwhile provides an efficient tool for government policy-makers to set out restrictions on water resource development in the area.  相似文献   

13.
Spatially distributed and varying natural phenomena encountered in geoscience and engineering problem solving are typically incompatible with Gaussian models, exhibiting nonlinear spatial patterns and complex, multiple-point connectivity of extreme values. Stochastic simulation of such phenomena is historically founded on second-order spatial statistical approaches, which are limited in their capacity to model complex spatial uncertainty. The newer multiple-point (MP) simulation framework addresses past limits by establishing the concept of a training image, and, arguably, has its own drawbacks. An alternative to current MP approaches is founded upon new high-order measures of spatial complexity, termed “high-order spatial cumulants.” These are combinations of moments of statistical parameters that characterize non-Gaussian random fields and can describe complex spatial information. Stochastic simulation of complex spatial processes is developed based on high-order spatial cumulants in the high-dimensional space of Legendre polynomials. Starting with discrete Legendre polynomials, a set of discrete orthogonal cumulants is introduced as a tool to characterize spatial shapes. Weighted orthonormal Legendre polynomials define the so-called Legendre cumulants that are high-order conditional spatial cumulants inferred from training images and are combined with available sparse data sets. Advantages of the high-order sequential simulation approach developed herein include the absence of any distribution-related assumptions and pre- or post-processing steps. The method is shown to generate realizations of complex spatial patterns, reproduce bimodal data distributions, data variograms, and high-order spatial cumulants of the data. In addition, it is shown that the available hard data dominate the simulation process and have a definitive effect on the simulated realizations, whereas the training images are only used to fill in high-order relations that cannot be inferred from data. Compared to the MP framework, the proposed approach is data-driven and consistently reconstructs the lower-order spatial complexity in the data used, in addition to high order.  相似文献   

14.
基于Voronoi图的空间信息多尺度表达   总被引:4,自引:0,他引:4  
空间信息多尺度表达是地理信息系统和遥感信息科学的重要研究内容之一。Voronoi图有效的几何规则和算法,为地图目标间的复杂空间关系提供了强大的描述和分析依据。讨论了在进行空间多尺度表达时,地物要素概括和符号化带来的取舍、相交、拥挤等空间冲突问题。根据计算几何的Voronoi、Delaunay原理,探讨了点群要素选取、线要素的相交、面要素的聚合和一致性简化,使其在视觉表达上更适合于人的视觉和认知心理学特点,更有利于空间数据进行分析、处理和可视化。  相似文献   

15.
利用空间统计分析方法能够扩展和加强GIS的空间分析功能,从而更深入地探索、分析、处理和解释经济发展的空间模式与空间关联。将空间统计分析与GIS相结合,探索了江西省各县域经济的空间分布格局与规律。结果表明,江西省各县域经济存在显著的空间自相关和聚集模式,经济发展在空间上具有明显的规律。  相似文献   

16.
17.
To-date geographical research on encounters has primarily comprised observation of naturalistic settings (both micro publics and everyday public spaces) or narrative accounts of encounters generated by conventional methods, this paper focuses on a contrived spatial experiment to create meaningful contact across difference. Inspired by, and drawing on insights from, Architecture – a discipline relatively neglected by geographers in recent times – we use a creative form of spatial play to stimulate groups of people to explore their differences and to develop shared understandings. Whereas previous studies have identified the importance of material objects in art projects and home spaces in mediating relations between people, surprisingly little attention has been paid to the physical configuration of space in work on encounters, despite the fact that geography is a spatial discipline. Here, we engage directly with the role of the form and function of space. Our spatial experiments demonstrate how paying attention to the materiality of micro-spaces rather than social relations alone, can provide insights into the generation of positive interactions by contributing to a greater understanding of how meaningful encounters happen, and what can be done to facilitate them. Specifically, by exploring the size and configuration of space, issues of ownership and surveillance, the relationship between primary and secondary space, and aural architecture this research identifies how working together to create a shared private or intimate space – might facilitate a sense of empowerment and the production of social relations characterised by democracy and inclusion.  相似文献   

18.
The spatial distributions of earth science and engineering phenomena under study are currently predicted from finite measurements and second-order geostatistical models. The latter models can be limiting, as geological systems are highly complex, non-Gaussian, and exhibit non-linear patterns of spatial connectivity. Non-linear and non-Gaussian high-order geostatistics based on spatial connectivity measures, namely spatial cumulants, are proposed as a new alternative modeling framework for spatial data. This framework has two parts. The first part is the definition, properties, and inference of spatial cumulants—including understanding the interrelation of cumulant characteristics with the in-situ behavior of geological entities or processes, as examined in this paper. The second part is the research on a random field model for simulation based on its high-order spatial cumulants. Mathematical definitions of non-Gaussian spatial random functions and their high-order spatial statistics are presented herein, stressing the notion of spatial cumulants. The calculation of spatial cumulants with spatial templates follows, including anisotropic experimental cumulants. Several examples of two- and three-dimensional images, including a diamond bearing kimberlite pipe from the Ekati Mine in Canada, are analyzed to assess the relations between cumulants and the spatial behavior of geological processes. Spatial cumulants of orders three to five are shown to capture directional multiple-point periodicity, connectivity including connectivity of extreme values, and spatial architecture. In addition, they provide substantial information on geometric characteristics and anisotropy of geological patterns. It is further shown that effects of complex spatial patterns are seen even if only subsets of all cumulant templates are computed. Compared to second-order statistics, cumulant maps are found to include a wealth of additional information from underlying geological patterns. Further work seeks to integrate this information in the predictive capabilities of a random field model.  相似文献   

19.
生态空间理论及其在生物入侵研究中的应用   总被引:5,自引:1,他引:5  
生态空间理论(theoryofspat ialecology)是对生态系统空间关系进行研究的一种理论,主要包括尺度、空间格局和镶嵌动态等。模型是研究空间关系的重要手段,其中莱文斯(Levins)模型、细胞自动机(cel lularautomata)模型和反应-扩散(React ion Di f fusion)模型是 3个基本的模型。尺度是生态学研究中的核心问题,对于不同的研究对象,应在相应的尺度上进行思考。空间异质性是不同尺度上的生态学过程的结果,同时它也影响各种生态学过程。随着人们对生物入侵的日益关注,空间生态学理论尤其是一些空间模型越来越多的应用于入侵和竞争的研究中。  相似文献   

20.
The spatial arrangement of sedimentary rock components is a fundamental property of sedimentary rocks. If we assume that the size, shape, and composition of sedimentary rock components (mineral grains, pores) carry useful petrologic information, there is no reason to assume that their spatial arrangement does not. Spatial arrangement has been discussed in terms of texture and fabric, but it has had little objective measurement or classification. This deficiency is primarily due to the difficulties associated with the quantification of spatial phenomena. However, using digital-imaging techniques it is possible to generate petrographic images from thin-sections and quantify the spatial arrangement of selected rock components using a two-dimensional (2D) Fourier transform. A Fourier transform creates a spectral representation of the image similar to an x-ray diffraction pattern. This paper presents the fundamental framework of 2D Fourier analysis in petrology. This type of analysis provides a means to quantify and analyze the spatial arrangement of rock components in an objective, mathematical framework. 2D Fourier power spectra can be used to characterize the type and degree of spatial order in an image, both in terms of the classical concepts of long-range and short-range order and in terms of spatial patterns characteristic of sedimentary rock. The clearly defined mathematical relationship between an image and its Fourier power spectrum provide the opportunity to define the 2D structure of an image in the same manner that x-ray diffraction patterns are used to map 3D structure in minerals. In addition, a 2D Fourier power spectrum is easily transformed into a radial power spectrum. Radial power spectra can be used to characterize the density of objects in an image. They also provide a valid means to compare and contrast images in a multivariate framework, regardless of the type of order. One of the most desirable properties of a Fourier transform is its reversibility. Using selected components of the power spectrum, the inverse transform can be used to build synthetic images, which highlight those petrologic components that most affect the power spectrum. The inverse transform provides the means to translate the results of analysis into meaningful petrologic characteristics.  相似文献   

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