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1.
The integration of GIS and spatial statistical analysis can occur in two different ways: embedding spatial statistical analysis into a GIS environment, or embedding selected GIS functions into a spatial statistical analysis environment. Attention has been given almost exclusively to the former in the past. This paper argues that the latter deserves more attention, especially with the rapid development of embeddable GIS component technology. However, because current statistical software packages have not yet provided the environment into which GIS components can be embedded, we explore the possibility of integrating GIS components and spatial statistical analysis in a current proprietary Database Management System (DBMS: Microsoft Access), which can be easily extended to incorporate statistical analysis capabilities. A conceptual framework for this integration is outlined, an interactive spatial statistical analysis module is presented, and an example is used to illustrate the advantage of this module.  相似文献   

2.
GIS elemental unit representations of spatial data are often defined in terms of points, lines and areas. However, another type of spatial data that is becoming frequently captured, but as yet is largely ignored in GIS, is that of video. While digital video recording is a commonly encountered medium in modern society and encompasses many forms, from simple personal camcorders through to sophisticated survey and surveillance systems, its geographical representation in a GIS has not been fully examined or realised. In the majority of cases the video footage is usually captured while the device and/or the objects being viewed are in motion. What is of particular interest is when video streams can be, or have been, associated with spatial data such as location and orientation to create geographically referenced videographic data, which, for simplicity, will be defined as spatial video. Fundamentally, the nature of video is to record space, so when spatial properties can be accurately acquired and associated with this footage, an important geographical element can be considered for integration and analysis within a GIS.

Existing spatial video systems, both commercial and research, are predominantly used in survey or LBS roles and are usually bespoke and application specific. These systems do not model spatial video to any recognised standards that is generalised to be both data and platform independent. They do not support GIS integration and/or analysis from a purely spatial content perspective. A video-image/remote-sensing centric approach prevails where usage options range from simple visualisation interfaces to interactive computer vision systems. What has been largely overlooked is a spatial approach where the inherent geographical extent recorded in each video frame can be modelled and used in a geo-spatial analysis context. While this modelling approach has not been fully realised, it does exist in a GIS form based on Open Geospatial Consortium standards, where the spatial context of video is defined in a structure called a ViewCone. However, a ViewCone only defines a 2D model of the geographical extent of each frame and is restricted to a three-or-five sided polygon representation.

Thus, this article examines the potential of modelling spatial video through the use of elemental data types within GIS; gives some examples of using this approach; describes some problems in using spatial video within GIS; and then demonstrates how these problems are being solved. This is done in three stages: Firstly, a detailed overview of spatial video in its current GIS role is provided – this is achieved through a complete introduction to the distinct elements of spatial video followed by a review of its use in both commercial and academic application areas. Secondly, a brief theoretical overview of an alternative GIS-constrained ViewCone data structure is given that defines a more flexible spatial video model for both 2D and 3D GIS analysis and visualisation. Thirdly, a selective sample of results is presented based on an implementation of this approach being applied to a constrained spatial video data source in a specific study area.  相似文献   

3.
区域喀斯特石漠化信息系统的设计研究   总被引:2,自引:0,他引:2  
本系统采用ArcGIS 软件作为基本平台, 以广西都安县为例, 借助其中的空间叠加分析与 地理统计分析方法, 构建了基于ArcObjects 的专业型GIS———区域喀斯特石漠化信息系统 (RKRDIS)。该系统是以喀斯特石漠化专业分析模型为核心, 以空间数据为信息材料, 以计算机网 络为传输载体, 解决喀斯特石漠化研究数据分析、查询、显示和管理等信息处理技术, 实现从“数 据”提取“信息”, 提供喀斯特石漠化的空间数据分析、动态监测、驱动诊断、预警分析、灾害评估和 辅助决策等多方面支持。  相似文献   

4.
Interactive statistical graphics are reviewed in the contexts of spatial data and geographical information systems (GIS). GIS provide the user with an active geographical view of the data—a map that can be used as an entry point to the data base. Prototype software—SPIDER—illustrates the possibilities of using statistical graphics as further views of the data, which can be made active and thus provide alternative means of querying the data. These views can be cross-referenced by 'linking'. It is argued that such a system can provide a very rich environment for pursuing exploratory statistical analysis of spatial data.  相似文献   

5.
遗传算法和GIS结合进行空间优化决策   总被引:15,自引:2,他引:13  
黎夏  叶嘉安 《地理学报》2004,59(5):745-753
资源的有效利用和管理往往涉及到空间的优化配置问题。例如需要在空间上确定n个设施的最佳位置。当选址问题涉及多个目标和不同的约束性条件时,就会变得十分复杂。利用一般的brute-force搜索方法无法对涉及高维数据的问题进行求解。利用遗传算法和GIS结合来解决复杂的空间优化配置问题,具有智能的搜索方法可以大大提高空间的搜索能力。在基于进化的优化过程中,根据GIS的空间数据来计算不同解决方案 (染色体) 的适应度。针对不同的应用目的,GIS可以给出不同的适应度函数。实验表明,所提出的方法比简单的搜索方法和退火算法有更大的优越性。该方法在处理复杂的空间优化问题有更好的表现。  相似文献   

6.
探索性空间分析及其与GIS集成模式探讨   总被引:3,自引:1,他引:2  
探索性空间分析基于让数据说话的理念,可以避免野值或非典型观测值的误导。在对探索性空间分析的基本原理和概念界定的基础上,探讨交互式和动态空间数据分析、地学可视化及可视化空间分布、确认性空间分析、空间数据挖掘等探索性空间分析的主要技术。由于统计分析软件和GIS的数据格式差异很大,直接将二者简单集成存在一定困难,因此切实可行的集成方式是采用对象连接和嵌入(OLE)技术,分别调用统计分析软件的探索性分析功能(或者函数)以及GIS的地图显示和空间分析功能,并进行必要开发,实现二者的集成。最后对探索性空间分析的发展方向进行展望。  相似文献   

7.
Statistical inference is important for all those who engage in the analysis of spatial data. The issue is becoming increasingly important given the explosion in the availability of spatial data and the proliferation of Geographic Information Systems (GIS) across different academic disciplines and application areas. The aim of this paper is to provide a brief overview of some of the concepts and controversies inherent in statistical inference in the hope of raising the level of awareness within the geographic information science community that different points of view exist when it comes to inference. We argue that the concept of statistical inference in spatial data analysis and spatial modelling is perhaps broader than many GIS users imagine. In particular, we argue that different types of inference exist and that process inference is just as valid as sample inference, even though the latter appears to dominate the GIS literature.  相似文献   

8.
Wildlife ecologists frequently make use of limited information on locations of a species of interest in combination with readily available GIS data to build models to predict space use. In addition to a wide range of statistical data models that are more commonly used, machine learning approaches provide another means to develop predictive spatial models. However, comparison of output from these two families of models for the same data set is not often carried out. It is important that wildlife managers understand the pitfalls and limitations when a single set of models is used with limited GIS data to try to predict and understand species distribution. To illustrate this, we carried out two sets of models (generalized linear mixed models (GLMMs) and boosted regression trees (BRTs)) to predict geographic occupancy of the eastern coyote (Canis latrans) on the island of Newfoundland, Canada. This exercise is illustrative of common spatial questions in wildlife research and management. Our results show that models vary depending on the approach (GLMM vs. BRT) and that, overall, BRT had higher predictive ability. Although machine learning has been criticized because it is not explicitly hypothesis-driven, it has been used in other areas of spatial modelling with success. Here, we demonstrate that it may be a useful approach for predicting wildlife space use and to generate hypotheses when data are limited. The results of this comparison can help to improve other models for species distributions and also guide future sampling and modelling initiatives.  相似文献   

9.
基于神经网络的元胞自动机及模拟复杂土地利用系统   总被引:57,自引:9,他引:57  
黎夏  叶嘉安 《地理研究》2005,24(1):19-27
本文提出了基于神经网络的元胞自动机(CellularAutomata),并将其用来模拟复杂的土地利用系统及其演变。国际上已经有许多利用元胞自动机进行城市模拟的研究,但这些模型往往局限于模拟从非城市用地到城市用地的转变。模拟多种土地利用的动态系统比一般模拟城市演化要复杂得多,需要使用许多空间变量和参数,而确定模型的参数值和模型结构有很大困难。本文通过神经网络、元胞自动机和GIS相结合来进行土地利用的动态模拟,并利用多时相的遥感分类图像来训练神经网络,能十分方便地确定模型参数和模型结构,消除常规模拟方法所带来的弊端。  相似文献   

10.
土地利用变化研究中的GIS空间分析方法及其应用   总被引:41,自引:7,他引:41  
土地利用变化研究尤其是空间变化研究 ,离不开 GIS的空间分析方法。该方法的数据基础主要是矢量格式的土地利用图件和遥感解译制图成果 ;模型基础包括 GIS的时空数据模型、属性数据模型和提取土地利用变化特征的原理模型 ;而数据处理过程则涉及GIS系统的数据转换功能、编辑功能、空间分析功能、数据库操作功能、空间统计分析功能以及图形显示功能等。本文结合北京市土地利用变化的实例分析 ,从上述三方面详细阐述了 GIS的空间分析方法及其在土地利用变化研究中的应用。  相似文献   

11.
The concept of place attachment has been studied extensively across multiple disciplines but only recently with empirical measurement using public participation GIS (PPGIS) and related crowd-sourcing mapping methods. This research trialed a spatially explicit method for identifying place attachment in a regional study in South Australia. Our research objectives were to (1) analyze and present the spatial results of the mapping method as a benchmark for future research, (2) compare mapped place attachment to the more common practice of mapping landscape values in PPGIS that comprise a values home range, (3) identify how participant socio-demographic and home location attributes influence place attachment, (4) provide some guidance for mapping place attachment in future research. We found large spatial variability in individual place attachment and mapped landscape values using both area and distance-based measures. The area of place attachment is influenced by occupational roles such as farming or conservation, as well as home location, especially in coastal versus non-coastal contexts. The spatial distribution of mapped landscape values or values home range is related to, but not identical to mapped place attachment with just over half of landscape values located outside the area of mapped place attachment. Economic livelihood values, as an indicator of place dependence, and social values, as an indicator of place identity, are more likely to be mapped within the place attachment area. Aggregated place attachment across participants in the region showed similar spatial intensity to aggregated values home range, but area-based assessment of place attachment and values home range are distorted by edge effects such as a coastline. To further develop the mapping of place attachment in PPGIS, we identify knowledge gaps from our study and offer suggestions for future research design.  相似文献   

12.
基于空间数据库技术的地籍管理系统研究   总被引:22,自引:0,他引:22  
潘瑜春  钟耳顺  梁军 《地理研究》2003,22(2):237-244
随着GIS应用的深入发展,以文件管理空间数据的方式已不能满足当前GIS应用的需要,而空间数据库技术正是为解决GIS应用的企业化和社会化问题而发展起来的新技术,空间数据库技术及其应用研究是当前GIS技术研究的热点。本文分析了空间数据对象、空间数据库、空间数据库技术及其实现,研究了基于空间数据库技术的地籍管理系统在空间数据共享、海量数据管理、大范围查询检索、分布式空间数据处理与维护、地籍制图、数据安全控制等方面的应用实现,通过具体应用系统建设,提出了基于空间数据库技术的地籍管理信息系统的解决方案。  相似文献   

13.
Optimal location search is frequently required in many urban applications for siting one or more facilities. However, the search may become very complex when it involves multiple sites, various constraints and multiple‐objectives. The exhaustive blind (brute‐force) search with high‐dimensional spatial data is infeasible in solving optimization problems because of a huge combinatorial solution space. Intelligent search algorithms can help to improve the performance of spatial search. This study will demonstrate that genetic algorithms can be used with Geographical Information systems (GIS) to effectively solve the spatial decision problems for optimally sitting n sites of a facility. Detailed population and transportation data from GIS are used to facilitate the calculation of fitness functions. Multiple planning objectives are also incorporated in the GA program. Experiments indicate that the proposed method has much better performance than simulated annealing and GIS neighborhood search methods. The GA method is very convenient in finding the solution with the highest utility value.  相似文献   

14.

Experimental variograms are crucial for most geostatistical studies. In kriging, for example, the variography has a direct influence on the interpolation weights. Despite the great importance of variogram estimators in predicting geostatistical features, they are commonly influenced by outliers in the dataset. The effect of some randomly spatially distributed outliers can mask the pattern of the experimental variogram and produce a destructuration effect, implying that the true data spatial continuity cannot be reproduced. In this paper, an algorithm to detect and remove the effect of outliers in experimental variograms using the Mahalanobis distance is proposed. An example of the algorithm’s application is presented, showing that the developed technique is able to satisfactorily detect and remove outliers from a variogram.

  相似文献   

15.
Abstract

This is the first of two papers elaborating a framework for embedding urban models within GIS. This framework is based upon using the display capabilities of GIS as the user interface to the conventional modelling process, beginning with data selection and analysis, moving to model specification and calibration, and thence to prediction. In this paper, we outline how various stages in this process based on purpose-built software outside the system, are accessed and operated through the GIS. We first deal with display based on thematic maps, surfaces, graphs and linked windows, standard to any data from whatever source, be it observations, model estimates or predictions. We then describe how various datasets are selected, how the spatial system can be partitioned or aggregated, and how rudimentary exploratory spatial data analysis enables scatterplots to be associated with thematic maps. We illustrate all these functions and operations using the proprietary GIS ARC-INFO applied to population data at the tract level in the Buffalo region. In the second part of the paper, various residential location models are outlined and the full modelling framework is assembled and demonstrated.  相似文献   

16.
Abstract

During the 1980s techniques for analysis of geographical patterns have been refined to the point that they may be applied to data from many fields. Quantitative spatial analysis and existing functions available in geographical information systems (GIS) enable computerized implementations of these spatial analysis methods. This paper describes the application of quantitative spatial analysis and GIS functions to analysis of language data, using the extensive files of the Linguistic Atlas of the Middle and South Atlantic States (LAMSAS). A brief review of recent development of using quantitative and statistical methods for analysing linguistic data is also included.  相似文献   

17.
基于GIS的区域经济空间结构演化研究--以河南省为例   总被引:1,自引:0,他引:1  
文章基于GIS,以河南省为例,对区域经济空间结构演化进行研究,通过对IDW方法和Kriging方法的比较,认为利用IDW方法对一个区域经济的空间结构进行研究更为合适。并且在区域经济研究中,利用GIS技术实现了经济数据与图形数据之间的关联,使区域经济的空间结构模式和发展趋势以图形的形式清晰直观地表现出来,增强了其可视性,更利于问题的发现、分析和解决,从而为促进区域经济空间结构的优化提供了科学依据。  相似文献   

18.
一种针对海洋GIS应用的建模方法研究   总被引:1,自引:0,他引:1  
为提高海洋GIS分析效率,使系统分析模型更简洁、更具领域特性,在分析相关针对GIS建模研究的基础上,利用UML的扩展机制,定义针对海洋GIS的面向对象建模语言UML-M。描述UML-M的元模型,研究基于UML-M的空间对象和空间关系的模型表现方法,包括简单空间对象、覆盖对象、复杂空间对象、时空对象等。实例分析表明,UML-M可以很好地应用在海洋GIS中。  相似文献   

19.
Abstract

A central problem in spatial analysis is the mapping of data for complex spatial fields using relatively simple data structures, such as those of a conventional GIS. This complexity can be measured using such indices as multi-scale variance, which reflects spatial autocorrelation, and multi-fractal dimension, which characterizes the values of fields. These indices are computed for three spatial processes: Gaussian noise, a simple mathematical function, and data for a random walk. Fractal analysis is then used to produce a vegetation map of the central region of California based on a satellite image. This analysis suggests that real world data lie on a continuum between the simple and the random, and that a major GIS challenge is the scientific representation and understanding of rapidly changing multi-scale fields.  相似文献   

20.
Use of GIS layers, in which the cell values represent fuzzy membership variables, is an effective method of combining subjective geological knowledge with empirical data in a neural network approach to mineral-prospectivity mapping. In this study, multilayer perceptron (MLP), neural networks are used to combine up to 17 regional exploration variables to predict the potential for orogenic gold deposits in the form of prospectivity maps in the Archean Kalgoorlie Terrane of Western Australia. Two types of fuzzy membership layers are used. In the first type of layer, the statistical relationships between known gold deposits and variables in the GIS thematic layer are used to determine fuzzy membership values. For example, GIS layers depicting solid geology and rock-type combinations of categorical data at the nearest lithological boundary for each cell are converted to fuzzy membership layers representing favorable lithologies and favorable lithological boundaries, respectively. This type of fuzzy-membership input is a useful alternative to the 1-of-N coding used for categorical inputs, particularly if there are a large number of classes. Rheological contrast at lithological boundaries is modeled using a second type of fuzzy membership layer, in which the assignment of fuzzy membership value, although based on geological field data, is subjective. The methods used here could be applied to a large range of subjective data (e.g., favorability of tectonic environment, host stratigraphy, or reactivation along major faults) currently used in regional exploration programs, but which normally would not be included as inputs in an empirical neural network approach.  相似文献   

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