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1.
Use of a Three-Domain Repesentation to Enhance GIS Support for Complex Spatiotemporal Queries 总被引：1，自引：0，他引：1
May Yuan 《Transactions in GIS》1999,3(2):137-159
As the development of Geographic Information Systems (GIS) proceeds to advanced scientific and societal applications, there is an emerging need to enhance GIS support for complex spatiotemporal queries. Dynamic GIS representations (as opposed to static, map-based representations) that can integrate proper data elements in the production of geographic information are required. This paper demonstrates the use of a three-domain representation that facilitates compilation of higher-level information (such as frequency and rate) from preliminary data records (such as time and location) stored in a database. The three-domain representation is compared with snapshot, space-time composite, and spatiotemporal object models using a sample data set for forest transitions. While the three-domain representation is a normalization of these data models, it offers a conceptual alternative that enables GIS to represent spatiotemporal behaviors of geographic entities, in addition to entities as well as histories at locations as emphasized in most GIS data models. The comparison shows that the three-domain representation has combined the strengths of the space-time composite and spatiotemporal object models. Moreover, it enables aggregations of analytical use along with dynamic mappings between geographic concepts and locations, a distinct capability that takes GIS query processing beyond the level of information support offered by static map-based data models. 相似文献
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遥感与地理信息系统数据的信息量及不确定性 总被引：8，自引：0，他引：8
讨论了遥感、GIS数据的不确定性与信息论中的不确定性间的联系，导出了GIS图形数据与遥感影像数据的信息量估算式，提出了位置疑义度和属性疑义度等概念。在统一的数学基础上，估算几何位置误差和属性正确率不足引起的不确定性，从而建立起遥感影像与GIS图形数据的信息量及不确定性的统一量度。 相似文献
3.
系统回顾了地理信息系统产生以来地理信息内涵发展与拓展的主要历程,指出地理信息的定义一直是在"空间+属性"的地图信息基本框架下逐步扩展,其发展历程经历了地图GIS、语义GIS、时空GIS和大数据GIS 4个不同的阶段,但仍无法满足时空大数据的分析和应用需求。从地理学研究的对象和内容出发,对地理学所需要的"地理信息"的内涵和外延进行了系统的梳理总结,提出了涵盖"空间定位""语义描述""属性特征""几何形态""演化过程""要素相互关系"的地理信息六要素表达模型。在地理定律和地理规律的指导下,面向地理现象空间分布、时空格局、演化过程、相互作用机理的集成表达、系统分析和高效管理,设计了六要素集成表达的几何代数统一GIS数据模型、地理规律与相互作用驱动的新型GIS数据结构、非结构化时空数据组织与存储等关键技术,为测绘地理信息走向地理科学信息提供了另一个理论基础与技术方法支撑,有助于提升GIS对地理格局、演化过程和要素相互作用等地理规律的组织、管理、表达和分析能力。 相似文献
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《制图学和地理信息科学》2013,40(4):315-318
Development of a temporal geographic information system (GIS) and spatio-temporal data modeling are key to incorporating time into geographic information science. This paper describes how to design and develop temporal GIS that will work with spatio-temporal data represented in various data models, and it introduces a prototype temporal GIS with a case study. In temporal GIS, the integration of multiple spatio-temporal representations is based on common spatial and temporal reference systems. In other words, a map window of temporal GIS visualizes spatio-temporal data valid at the same time within one spatial area. To achieve such visualization, separate data editing and query modules are required for each spatio-temporal data model (STDM). In the temporal query interface, after a user specifies a time, the system automatically hires correspondent modules to retrieve spatio-temporal data valid at that time. Besides temporal queries common to all STDMs, each module may provide additional temporal query capabilities specific to that STDM. In the case study, I implement a prototype temporal GIS for three STDMs. The examples of query and visualization, which use three datasets (census data, land use/land cover, and elevation data) demonstrate the prototype temporal GIS can integrate multiple temporal representations. 相似文献
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关于线状地理特征空间关系的自然语言描述的形式化表达 总被引：1，自引：0，他引：1
目前的地理信息系统都使用定量的方法存储和查询空间信息,不能反映人们的定性思维方式,因此它表达地理空间信息的能力受到限制。在关于空间关系的自然语言描述的调查的基础上,本文定义了一组能反映线状物体空间关系的度量指标,结合反映拓扑关系的定量指标,使用决策树的数据挖掘算法,对调查结果进行分析,形式化了描述空间关系的自然语言词汇,建立了模糊的自然语言表达和图形的几何特征之间的联系。自然语言形式化后得到的规则可用于空间关系的自然语言查询系统。 相似文献
8.
The representation of place is a key theoretical advancement that geographic information science can offer to improve the understanding of environmental determinants of health, but developing robust computational representations of place requires a substantial departure from conventional notions of geographic representation in GIS. Unlike conventional GIS representations based on either objects or locations, we suggest that place representation should incorporate dynamic subjective, experiential, and relational aspects of place, as the influence of place on health behavior concerns not only the features that can be objectively observed at a particular location but also the environmental perceptions of the individual, as molded by biological, social, and experiential characteristics. In addition, assessments of environmental exposures on health outcomes should focus on individuals' time–activity patterns and microenvironment profiles, which form a potentially unique personalized exposure environment for each individual. Addressing these representational challenges via collaborative research has the potential to advance both geographic information science and health research. 相似文献
9.
廖伟华 《测绘与空间地理信息》2011,34(2):65-66,69
GIS属性数据作为GIS实体的属性,具有模糊性、不确定性。由GIS实体对象和对象的属性组成的二元关系满足近似空间的特性。本研究从GIS信息系统的对象、属性出发,利用格概念,认为GIS属性数据集合可以构成偏序关系,并且(P(A),)构成一个完备的偏序格。如果从属性链的角度分析,GIS实体集在的细分划分空间关系下,可以构成分层递阶近似空间,并且随着属性个数的增加,知识颗粒将逐渐"细化"。 相似文献
10.
Analytical Modelling of Positional and Thematic Uncertainties in the Integration of Remote Sensing and Geographical Information Systems 总被引：1，自引：0，他引：1
This paper describes three aspects of uncertainty in geographical information systems (GIS) and remote sensing. First, the positional uncertainty of an area object in a GIS is discussed as a function of positional uncertainties of line segments and boundary line features. Second, the thematic uncertainty of a classified remote sensing image is described using the probability vectors from a maximum likelihood classification. Third, the "S-band" model is used to quantify uncertainties after combining GIS and remote sensing data. 相似文献
11.
Assessing Similarity of Geographic Processes and Events 总被引：6，自引：0，他引：6
The increased availability of spatiotemporal data collected from satellite imagery and other remote sensors provides opportunities for enhanced analysis of geographic phenomena. Much of the new data includes regular snapshots of the environment. Comparison of these snapshots can provide information about changes to the phenomena of interest. However, conventional GIS data models and analytical tools lack capabilities to adequately handle massive multidimensional data. One of the fundamental tools necessary to meet such challenges is query support to retrieve and summarize data according to dynamic geographic phenomena, such as geographic events and processes, of interest. Such query support depends upon abilities to assess spatiotemporal similarity so that data representing geographic events that exhibit the spatiotemporal characteristics of interest can be identified in a GIS database. To this end, this paper introduces a method to assess similarity of geographic events and processes (such as storms) based on their spatiotemporal characteristics (such as distribution of precipitation). We developed six indices to capture static and dynamic characteristics of geographic events and applied the Dynamic Time Warping method to temporal sequences of the six indices to examine the similarity among these events. With a case study, we demonstrated the proposed indices and method capable of comparing spatiotemporal characteristics of events as recorded in a GIS database and categorizing spatiotemporal data into groups of events according to their behavior in space and time. 相似文献
12.
地理要素的时空变化分析对于了解和掌握地表的规律性有着重要的作用。利用地面站点观测、实地调查等传统方式获取数据,对地理要素进行时空变化分析是最常用的方法。但该类方法往往表现的是"点尺度"观测,不能在大尺度情况下准确地反映地表的时空变化信息。遥感卫星能以一定的时间间隔获得空间连续的对地"面尺度"观测数据,然而其特定的空间和时间分辨率使其获取的地表信息仍十分有限。同时地表的空间异质性和个别地表短时间内的快速变化,使得利用遥感数据对地理要素进行时空变化分析时,时空变化分析结果会随观测尺度而发生改变。本文从空间尺度和时间尺度两方面综述遥感数据时空尺度对地理要素的时空变化分析产生的影响和原因,并针对这些问题总结了减小时空尺度对结果不确定性影响的现行方法。可以通过多源遥感协同观测和反演、尺度转换、空间建模等方法减小空间尺度引起的不确定性;通过联合多时相遥感数据的方法减小时间尺度引起的不确定性。在实际应用中,应根据所观测地理要素的实际情况,综合分析选择合适的方法。 相似文献
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Dynamic GIS Case Studies: Wildfire Evacuation and Volunteered Geographic Information 总被引：1，自引：0，他引：1
Edward Pultar Martin Raubal Thomas J Cova Michael F Goodchild 《Transactions in GIS》2009,13(S1):85-104
Incorporating the temporal element into traditional GIS is a challenge that has been researched for many years and has many proposed solutions. The implemented system "Extended Dynamic GIS" or EDGIS is based on the "geo-atom" and Space Time Point (STP). EDGIS provides a platform for spatiotemporal data representation, storage, and query in order to address the need for a dynamic GIS to manage complex geographic data types. The system has the capability of executing spatiotemporal object interaction queries (OIQs) such as crossing and coincidence of field-objects and object-fields. In this article existing dynamic GIS analysis techniques are further improved and enhanced through exploration of more in-depth case studies. Further examined here are applications to wildfire evacuation modeling and travel scenarios of urban environments with individuals providing volunteered geographic information (VGI). The EDGIS platform provides a means for interacting with a range of dynamic geographic phenomena. The areas of transportation, location based services (LBS), hazards, and geo-sensor networks provide challenges intertwined with the above applications as well as additional challenges pertinent to the ongoing GIScience research topic of spatiotemporal GIS. Using EDGIS to explore the described case studies of wildfire evacuation as well as VGI provides the advancements described above and demonstrates implemented uses for dynamic GIS. 相似文献
15.
A New Combined Assessment of Mixed Uncertainty in Spatial Models: Conceptualization and Implementation 
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下载免费PDF全文 Uncertainty quantification is not often performed in spatial modeling applications, especially when there is a mixture of probabilistic and non‐probabilistic uncertainties. Furthermore, the effect of positional uncertainty is often not assessed, despite its relevance to geographical applications. Although there has been much work in investigating the aforementioned types of uncertainty in isolation, combined approaches have not been much researched. This has resulted in a lack of tools for conducting mixed uncertainty analyses that include positional uncertainty. This research addresses the issue by first presenting a new, flexible, simulation‐oriented conceptualization of positional uncertainty in geographic objects called F‐Objects. F‐Objects accommodates various representations of uncertainty, while remaining conceptually simple. Second, a new Python‐based framework is introduced, termed Wiggly and capable of conducting mixed uncertainty propagation using fuzzy Monte Carlo simulation (FMCS). FMCS combines both traditional Monte Carlo with fuzzy analysis in a so‐called hybrid approach. F‐Objects is implemented within the Wiggly framework, resulting in a tool capable of considering any combination of: (1) probabilistic variables; (2) fuzzy variables; and (3) positional uncertainty of objects (probabilistic/fuzzy). Finally, a realistic GIS‐based groundwater contamination problem demonstrates how F‐Objects and Wiggly can be used to assess the effect of positional uncertainty. 相似文献
16.
王家耀 《武汉大学学报(信息科学版)》2022,47(10):1535-1545
在Geographic Information System（GIS）近60年的发展演进中,理论和技术都取得了长足的进步;应用领域扩大到社会的方方面面,社会影响力越来越大;体系结构、开发模式和服务模式等都发生了深刻的变化。为了推动GISystem进一步向前发展,在综述GIS中之“S”的三种含义即System（系统）、Science（科学）和Service（服务）以及GIS近60年来取得的丰硕成果的基础上,重点就以下三个问题进行了讨论:（1）如何认识地理信息系统（GISystem）。首先解析地理信息系统的三个关键词（系统、信息、地理信息）,据此论述了地理信息系统的内涵,分析了地理信息系统同地图、计算机地图制图、地图数据库的关系,认为地理信息系统源于又超越了地图、计算机地图制图和地图数据库,并认为地理信息系统具有装备的特性。（2）地理信息系统是怎样发展演进的。重点分析了由“地理信息系统”到“地理信息服务”的发展演进的社会需求背景、技术背景、学科背景,从应用领域、数据资源和功能的扩展及体系结构、开发模式和服务模式等方面,分析了地理信息系统发展演进的主要表现。（3）地理信息系统的未来发展将走向何方。首先,讨论了正确理解地理信息系统应用领域扩展的问题,认为应用领域的扩展不可能是“无边无际”的;地理信息系统的未来发展必须面向国家经济建设和国防建设急需;在分析比较现有三种GISystem服务模式的基础上,认为采用“网格集成”与“弹性云”的“混合式”技术体制是GISystem服务模式的最佳选择;提出了基于“网格集成”与“弹性云”的“混合式”的时空大数据平台技术实现必须解决的6个关键技术问题和“时空大数据平台”的应用模式。 相似文献
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《制图学和地理信息科学》2013,40(4):291-299
Nautical information is one example of spatial data with a strong temporal component. This paper describes the methods of temporal data representation to be used in a National Ocean Service (NOS) Automated Nautical Charting System (ANCS II). The system will be capable of tracing spatial change over time and of tracking cartographic and data-base procedures within the agency. The discussion describes a method of spatiotemporal representation within traditional geographic information systems (GIS) data structures, draws a distinction between information-oriented and production-oriented temporality, and identifies three fundamental elements of temporal metadata. 相似文献
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GIS中属性不确定性的处理方法及其发展 总被引：6，自引：0，他引：6
属性数据的不确定直接影响决策的准确性和可靠性,特别是对侧重于属性分析的领域,在研究属性不确定性的基础上,分析了GIS中的主要处理方法及其研究进展,具体地就基于GIS的模型,概率论及数理统计学,模糊集合,云理论,粗集等方法及进展进行讨论. 相似文献
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一种面向对象的时空数据模型 总被引：62，自引：2，他引：62
地理信息系统中，时间、空间和属性是信息的3种基本成分，理想的地理信息系统应支持信息的时态性，对时空数据进行统一的模拟和管理。由于当前的地理信息系统软件难以处理时态现象，时空数据模型已成为GIS领域的一个研究热点。首先对当前时空数据模型研究现状进行了分析，在此基础上，提出了一种面向对象时空数据模型，并从3个方面描述了该模型的数据结构，包括时空对象结构、时空数据组织方式和时空数据存贮方式。 相似文献
20.
In geographic information science, a plethora of different approaches and methods is used to assess the similarity of movement. Some of these approaches term two moving objects similar if they share akin paths. Others require objects to move at similar speed and yet others consider movement similar if it occurs at the same time. We believe that a structured and comprehensive classification of movement comparison measures is missing. We argue that such a classification not only depicts the status quo of qualitative and quantitative movement analysis, but also allows for identifying those aspects of movement for which similarity measures are scarce or entirely missing.In this review paper we, first, decompose movement into its spatial, temporal, and spatiotemporal movement parameters. A movement parameter is a physical quantity of movement, such as speed, spatial path, or temporal duration. For each of these parameters we then review qualitative and quantitative methods of how to compare movement. Thus, we provide a systematic and comprehensive classification of different movement similarity measures used in geographic information science. This classification is a valuable first step toward a GIS toolbox comprising all relevant movement comparison methods. 相似文献