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1.
Multi-resolution spatial data always contain the inconsistencies of topological, directional, and metric relations due to measurement methods, data acquisition approaches, and map generalization algorithms. Therefore, checking these inconsistencies is critical for maintaining the integrity of multi-resolution or multi-source spatial data. To date, research has focused on the topological consistency, while the directional consistency at different resolutions has been largely overlooked. In this study we developed computation methods to derive the direction relations between coarse spatial objects from the relations between detailed objects. Then, the consistency of direction relations at different resolutions can be evaluated by checking whether the derived relations are compatible with the relations computed from the coarse objects in multi-resolution spatial data. The methods in this study modeled explicitly the scale effects of direction relations induced by the map generalization operator – merging, thus they are efficient for evaluating consistency. The directional consistency is an essential complement to topological and object-based consistencies.  相似文献   

2.
Qualitative knowledge representation of spatial locations and relations is popular in many text-based media, for example, postings on social networks, news reports, and encyclopedia, as representing qualitative spatial locations is indispensable to infer spatial knowledge from them. However, an integrative model capable of handling direction-based locations of various spatial objects is missing. This study presents an integrative representation and inference framework about direction-based qualitative locations for points, lines, and polygons. In the framework, direction partitions of different types of reference objects are first unified to create a partition consisting of cells, segments, and corners. They serve as a frame of reference to locate spatial objects (e.g., points, lines, and polygons). Qualitative relations are then defined to relate spatial objects to the elements in a cell partition, and to form the model of qualitative locations. Last, based on the integrative representation, location-based reasoning mechanism is presented to derive topological relations between objects from their locations, such as point–point, line–line, point–line, point–polygon, line–polygon, and polygon–polygon relations. The presented model can locate any type of spatial objects in a frame of reference composed of points, lines, and polygons, and derive topological relations between any pairs of objects from the locations in a unified method.  相似文献   

3.
多尺度地图空间相似关系基本问题研究   总被引:8,自引:0,他引:8  
基于多尺度地图数据库建设中地图自动综合的终止判断条件,引出多尺度地图空间相似关系问题。基于集合论给出空间相似关系的定义,论述空间相似关系的5个性质,即反身性、对称性、非传递性、多尺度自相似性与尺度依赖性;并从图形相似和属性相似的角度论述多尺度地图空间相似关系的分类体系。该成果是研究地图自动综合和地图空间相似查询等的基础。  相似文献   

4.
The spatial structures of China’s Major Function Zoning are important constraining indicators in all types of spatial planning and key parameters for accurately downscaling major functions.Taking the proportion of urbanization zones,agricultural development zones and ecological security zones as the basic parameter,this paper explores the spatial structures of major function zoning at different scales using spatial statistics,spatial modeling and landscape metrics methods.The results show:First,major function zones have spatial gradient structures,which are prominently represented by latitudinal and longitudinal gradients,a coastal distance gradient,and an eastern-central-western gradient.Second,the pole-axis system structure and core-periphery structure exist at provincial scales.The general principle of the pole-axis structure is that as one moves along the distance axis,the proportion of urbanization zones decreases and the proportion of ecological security zones increases.This also means that the proportion of different function zones has a ring-shaped spatial differentiation principle with distance from the core.Third,there is a spatial mosaic structure at the city and county scale.This spatial mosaic structure has features of both spatial heterogeneity,such as agglomeration and dispersion,as well as of mutual,adjacent topological correlation and spatial proximity.The results of this study contribute to scientific knowledge on major function zones and the principles of spatial organization,and it acts as an important reference for China’s integrated geographical zoning.  相似文献   

5.
旅游景区合理布局是实现黄河流域旅游业高质量发展的内在要求与根本保障,识别景区空间格局及其影响因素如何随尺度发生变化,对黄河流域的景区多层级统筹管理具有重要现实意义。基于地理因素的空间尺度效应,从县域、市域、集聚区3个尺度构建了分析框架,利用统计与GIS技术揭示黄河流域A级景区多尺度空间格局,运用地理探测器、空间叠加分析等揭示各尺度影响因素及其差异特征。结果表明:(1)黄河流域A级景区整体呈东部和南部密集、西部和北部稀疏的空间格局,流域南部形成一个中高密度弧形带。随着研究尺度增大,景区集聚范围逐渐扩大,集聚程度逐渐降低;(2)县域尺度上,全国重点文物保护单位密度对景区格局影响程度最大,其次是植被覆盖度、年降水量、到最近河流距离、国家湿地公园密度。人口密度是市域尺度影响程度最大的主导因素,非主导因素在与各主导因素交互后形成强烈的增强效应。集聚区尺度景区格局主要受年降水量、植被覆盖度等自然环境因素的刚性约束;(3)3个尺度的影响因素明显不同,不同尺度景区格局并不是主导因子简单组合或累积的结果,而是自然环境、旅游资源、社会经济及区位复杂交互后的产物。  相似文献   

6.
Abstract

Growth in the available quantities of digital geographical data has led to major problems in maintaining and integrating data from multiple sources, required by users at differing levels of generalization. Existing GIS and associated database management systems provide few facilities specifically intended for handling spatial data at multiple scales and require time consuming manual intervention to control update and retain consistency between representations. In this paper the GEODYSSEY conceptual design for a multi-scale, multiple representation spatial database is presented and the results of experimental implementation of several aspects of the design are described. Object-oriented, deductive and procedural programming techniques have been applied in several contexts: automated update software, using probabilistic reasoning; deductive query processing using explicit stored semantic and spatial relations combined with geometric data; multiresolution spatial data access methods combining poini, line, area and surface geometry; and triangulation-based generalization software that detects and resolves topological inconsistency.  相似文献   

7.
Scale variance is highly sensitive to multi-scale patterns of variables, which is advantageous in identifying spatial hierarchy and characteristic scale(s). However, the significance of peak(s) in scale variance cannot be statistically tested, and different spatial patterns may be obtained when different zoning systems are used to calculate scale variance. To address these two problems, this study compared the scale levels with peaks in scale variance and the scale levels at which there were breaks in the nature of spatial autocorrelation as identified by shifts in Moran's I scalogram. The estimates for three simulated landscapes showed that accordance between scale levels identified employing the two methods can be used to evaluate the significance of peaks in scale variance and choose a more reasonable zoning system. The approach of scale variance analysis coupled with Moran's I scalogram was also applied to the Xilin River Basin of Inner Mongolia, China. The most vital characteristic scale (64 × 32 km) identified for the growing-season net ecosystem productivity (NEP) of the basin was validated by other spatial pattern analysis methods such as semi-variogram, Moran's I correlogram, and wavelet variance analyses, and the directionality of the chosen zoning systems was found to be similar to the orientation of actual dominant vegetation type patches. The results demonstrate that Moran's I scalogram can be used to improve the interpretation of the results of scale variance analysis and increase the reliability of scale variance analysis for landscapes having a repetitive patch pattern or gradient variation and that the proposed approach is suitable for identifying the hierarchy and the characteristic scales of patterns or processes. In summary, this study used a simple approach to solve two problems in scale variance analysis, thereby improving the methodology and enhancing the theoretical basis of multi-scale analysis.  相似文献   

8.
土地利用类型结构的多尺度转换特征   总被引:10,自引:4,他引:6  
朱晓华  李亚云 《地理研究》2008,27(6):1235-1242
尺度一直是LUCC到GLP研究所关注的重要问题。以不同比例尺的辽宁省土地利用数据为例,以贵州省土地利用数据进行验证,系统探讨了土地利用类型结构在不同尺度间可能存在的转换特征。结论如下:(1)辽宁省土地利用的分形结构跨1 ∶ 10万、1 ∶ 50万、1 ∶ 100万这3个比例尺客观存在;(2)对不同比例尺的同一区域不同土地利用类型而言,各土地利用类型分维在不同比例尺之间存在的响应关系并不一致,某些土地利用类型的分维随着比例尺由1 ∶ 10万向1 ∶ 50万再向1 ∶ 100万的变小,分维呈现变大趋势,而某些土地利用类型的分维随比例尺的变化并不如此,所以,对于不同的土地利用类型而言存在一定的差别,不可一概而论;(3)不同尺度间的土地利用类型结构只能够在两两连续间隔的两种比例尺土地分维之间建立起关系显著的定量关系模型。所得结论对科学认知土地结构空间配置的多尺度特征以及建立相应尺度转换模型具有积极的参考意义。  相似文献   

9.
The purpose of this paper is to propose a new notion on prominent areas of a city defined by two types of comprehensive prominence for identifying urban spatial structure. Not only geometric attributes and topological attributes but also thematic attributes of irregular areas (e.g. districts of a city) are used to define these indices. In the paper, first the topological prominence related to geometric attributes such as size, location, and shape of areas is constructed by spatial weight matrix. Second, for finding comprehensive prominences, the principle axis factor model is adopted, and the first factor score is defined as the comprehensive prominence 1. Then, the proportion of thematic attributes of each area occupied in across the city is used to define the comprehensive prominence 2. Finally, we use these comprehensive prominences to extract some important regions in Matsudo City of Chiba Prefecture in Japan. The areas composing those regions show a high topological prominence, have a large population, have many offices, and are located around the train station.  相似文献   

10.
家庭选择居住地的行为天然具有空间性, 因而空间异质性效应是家庭居住地选址建模不可忽视的因素。传统的居住地选址模型基于空间一致性假设, 即假设影响因素对家庭的居住地选择行为的影响在空间上一致, 因而忽略了空间异质性效应。基于多项Logit 模型构建了居住地选址模型, 并在两个空间尺度和5 个子区域中分别应用该模型, 来反映影响因素的影响作用在空间上的变化。以美国佛罗里达州橙县家庭选址为例进行实证研究, 结果表明:家庭居住地选址行为的影响因素在不同的空间位置和空间尺度上具有不同的作用, 因而存在显著的空间异质性。尽管以美国地区为例, 但所得结论对国内案例区研究同样具有借鉴意义。  相似文献   

11.
基于区域合并影像分割技术的多尺度地表景观分析   总被引:6,自引:1,他引:5  
分割是面向对象影像分析的前提,景观空间异质性特征给遥感信息获取提出了多尺度的要求。影像分割的多尺度分析以尺度效应与对象异质性最小原则为前提,描述多尺度效应分析的必要性与可行性。基于区域合并的分割原理与方法,为多尺度影像分析提供理论与技术支持,在两个样区进行多尺度影像分割技术的应用实践,分析基于区域合并的多尺度分割数据的几何丰富度与语义丰富度。  相似文献   

12.
Spatial data can be represented at different scales, and this leads to the issue of multi-scale spatial representation. Multi-scale spatial representation has been widely applied to online mapping products (e.g., Google Maps and Yahoo Maps). However, in most current products, multi-scale representation can only be achieved through a series of maps at fixed scales, resulting in a discontinuity (i.e., with jumps) in the transformation between scales and a mismatch between the available scales and users' desired scales. Therefore, it is very desirable to achieve smoothly continuous multi-scale spatial representations. This article describes an integrated approach to build a hierarchical structure of a road network for continuous multi-scale representation purposes, especially continuous selective omission of roads in a network. In this hierarchical structure, the linear and areal hierarchies are constructed, respectively, using two existing approaches for the linear and areal patterns in a road network. Continuous multi-scale representation of a road network can be achieved by searching in these hierarchies. This approach is validated by applying it to two study areas, and the results are evaluated by both quantitative analysis with two measures (i.e., similarity and average connectivity) and visual inspection. Experimental results show that this integrated approach performs better than existing approaches, especially in terms of preservation of connectivity and patterns of a road network. With this approach, efficient and continuous multi-scale selective omission of road networks becomes feasible.  相似文献   

13.
国土空间治理是新时期中国国土资源开发、利用、保护、整治及修复的重要战略手段。当前国土空间治理体系在空间尺度上存在主导功能衔接失配,亟待统一不同尺度空间单元以统筹治理边界、提高治理效率。据此,面向传统治理单元管制边界的针对性问题导向,提出“通过不同理念或方式界定的国土空间单元具有不同的功能导向”等研究假设,并构建土地利用冲突、生态系统障碍、社会发展状态等指数在行政区划单元、自然生态单元、社会发展单元等治理单元上以成都市为例进行验证。结果表明,研究区国土空间治理问题属性的空间格局特征差异化显著,人类活动范围与自然环境限制之间的矛盾是导致区域内治理问题发生的核心因素。在空间相关性分析方面,所有治理问题类型在不同空间单元上均呈现显著自相关性,且均通过0.05显著性检验,但不同空间单元具有理论指向性特点。其中,社会发展单元更适合解决经济发展动力差距问题,自然生态单元更适合解决生态系统连通阻力问题,行政区划单元则更适合解决事权管理冲突问题。在此基础上,利用景观单元协调不同尺度空间单元的问题属性,将研究区划分为高山地带发展动力衰弱型(22.98%)、丘陵地带治理属性均衡型(11.55%)、乡村地区管理冲突加剧型(44.57%)、城乡边缘区发展主导复合型(9.44%)、核心建成区连通阻力增强型(11.46%)5类空间,进而实现多尺度空间单元的跨行政区融合路径。综合而言,有必要建立管理-保护-发展功能嵌套的空间单元集成体系,通过细化景观尺度将权力和责任从政府机构拓展至更广泛的行动参与者,系统地提升国土空间治理效能。  相似文献   

14.
An inconsistency measure can be used to compare the quality of different data sets and to quantify the cost of data cleaning. In traditional relational databases, inconsistency is defined in terms of constraints that use comparison operators between attributes. Inconsistency measures for traditional databases cannot be applied to spatial data sets because spatial objects are complex and the constraints are typically defined using spatial relations. This paper proposes an inconsistency measure to evaluate how dirty a spatial data set is with respect to a set of integrity constraints that define the topological relations that should hold between objects in the data set. The paper starts by reviewing different approaches to quantify the degree of inconsistency and showing that they are not suitable for the problem. Then, the inconsistency measure of a data set is defined in terms of the degree in which each spatial object in the data set violates topological constraints, and the possible representations of spatial objects are points, curves, and surfaces. Finally, an experimental evaluation demonstrates the applicability of the proposed inconsistency measure and compares it with previously existing approaches.  相似文献   

15.
东北三省区域经济差异的多尺度与多机制研究   总被引:1,自引:2,他引:1  
江孝君  杨青山  刘杰  沈方  刘鉴 《地理科学》2020,40(3):383-392
基于多尺度与多机制分析框架,采用差异测度及尺度分解指数、ESDA及回归分析等方法,从省级、地级、县级3个尺度分析了2003-2016年东北三省经济差异的时空特征及驱动机制。研究表明:各尺度区域经济绝对和相对差异均较为明显,呈县级>地级>省级的尺度格局;经济差异总体呈下降趋势,各尺度差异及对总差异贡献率呈市间差异>市内差异>省间差异。各尺度区域经济发展呈显著空间集聚特征,关联类型以正相关为主且低-低(LL)型占主导地位,越小的尺度空间依赖性和异质性越明显。区域经济发展空间上呈现“两核两带”的格局,即以辽中南和哈长城市群为核心,以哈大轴和东部沿边轴为发展轴带。地理区位与要素禀赋、战略政策与财政扶持、行政分割与等级体制、开放带动与空间优化等诸多要素综合作用于区域经济差异时空格局的演化。  相似文献   

16.
多尺度地理空间点群目标相似关系的计算研究   总被引:1,自引:0,他引:1  
研究多尺度地理空间点群目标相似关系的计算问题.基于4类点群信息,将点群目标包含的信息重新分成统计信息、专题信息、拓扑信息、几何信息和度量信息,这5类信息是影响点群相似性程度的主要因子.根据这5类信息描述参数的特点,给出了各个因子的相似度计算公式,建立了多尺度地理空间点群目标相似关系的计算模型,并通过算例验证了该模型的可行性与有效性,为地图综合质量的评价提供了一种新方法.  相似文献   

17.
空间关系理论研究是当前GIS界重点研究的前沿课题之一,但就目前研究成果看,空间关系理论中的拓扑关系和方向关系的理论研究多采用独立的描述模型,影响了空间推理和空间表达的精度。该文在分析拓扑关系和方向关系描述模型的基础上,提出将拓扑关系和方向关系定性表示相结合的TD模型,并用实例说明该模型能较全面地描述空间对象的空间关系。  相似文献   

18.
基于空间关系和空间推理理论,结合MGIS领域的需求建立巷道三维拓扑网络模型,研究巷道三维空间关系推理的算法及业务逻辑实现;开发巷道三维拓扑自动生成系统,实现了巷道空间与属性数据管理、三维拓扑自动处理、多尺度成果输出及基于三维拓扑的路径查询,为基于巷道的通风、运输、避灾、多尺度变换等应用奠定了基础。  相似文献   

19.
针对现有空间数据划分方法普遍存在的不考虑空间对象自身大小和相邻对象空间关系对数据划分的影响等问题,提出一种基于Hilbert空间填充曲线层次分解的空间数据划分方法。该方法使用Hilbert曲线保持划分后空间数据之间的邻近性,利用少数子网格的层次分解避免对整个空间范围的密集划分,减少空间对象的Hilbert编码计算和排序时间;通过计算划分区域平均数据量和子网格内空间对象大小,确定合适的层次分解参数,实现各划分区域内空间数据量均衡。实验表明,该方法提高了空间数据的划分效率,能够保持划分后空间数据之间的邻近性和各个分区数据量的平衡。  相似文献   

20.
黄河三角洲多尺度土壤盐分的空间分异   总被引:20,自引:5,他引:15  
王红  宫鹏  刘高焕 《地理研究》2006,25(4):649-658
本文利用多尺度采样数据,探索了两个深度土壤盐分的空间分异,分析了不同尺度、深度土壤盐分的变异系数和空间相关性(结构方差与基台值之比)的变化,揭示了形成这种空间变异的地貌因素,最后利用普通克立格(ordinary kriging)方法对土壤盐分的分布进行了估测。分析发现,研究区土壤盐分的空间变异具有三个尺度。随着采样间隔的增加和区域的扩大,盐分分布空间相关性增强,且下层比上层具有更高的空间相关性。地貌因素(微地貌类型、坡度和高程)均具有较高的空间相关性,当与地貌因素关系密切时,该尺度及深度的土壤盐分空间相关性就大;反之,则小,这时可能主要受具有较小空间相关性其他因子的影响(如人为活动)。最后对合理的土壤采样提出了建议。  相似文献   

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