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To improve the formal integration of verbally given spatial information in a geographical information system, a methodology for converting such information to a geographical representation was developed. This was applied to examples of a spatial-related analysis of natural language text messages in the domain of disaster management. This article presents an approach for such a conversion by using a suitable knowledge representation as well as formal modelling structures. The structures are provided by an ontology-supported knowledge base. With respect to spatial uncertainty, a formal representation based on possibility theory was defined. Moreover, a cluster algorithm was developed for handling information of different sources and building a spatial context.  相似文献   

3.
This paper is concerned with some issues related to the changes in the role, properties and characteristics of cartography in connection with the transition of mankind from the industrial age to the information (post-industrial) age. Emphasis is placed on the essence of the process of perception of the environment by humans through data provided to them where the object of perception and the subject perceiving information are located at different points of the space-time continuum. The study identifies eight characteristic features of the information age, the new challenges and requirements, the possibilities of information society, and the related new tasks of cartographic support of the economy. It is shown that the main difference of the information age from the industrial age implies a transition from the commodity-producing economy to the economy of information services. Based on this, it is concluded that there is a need for the provision of various cartographic services, such as the generation of cartographic information as requested as well as supplying it to various users. Seven main statements are formulated, which characterize the peculiarities, properties and methodological foundations of cartography under the new conditions. The definitions of the role and subject of cartography in the information age are suggested. An interpretation is given to the term “neocartography”, and its main characteristics are presented. The notion of a multipurpose cartographic resource is introduced.  相似文献   

4.
Lane-based road network information, such as lane geometry, destination, lane changing, and turning information, is important in vehicle navigation, driving assistance system, and autonomous driving. Such information, when available, is mainly input manually. However, manual methods for creating and updating data are not only costly but also time-consuming, labor-intensive, and prone to long delays. This paper proposes a hierarchical polygonization method for automatic generation and updating of lane-level road network data for navigation from a road marking database that is managed by government transport department created by digitizing or extraction from aerial images. The proposed method extends the hierarchy of a road structure from ‘road–carriageway–lane’ to ‘road–carriageway–lane–basic lane’. Basic lane polygons are constructed from longitudinal road markings, and their associated navigational attributes, such as turning information and speed limit, are obtained from transverse road markings by a feature-in-polygon overlay approach. A hierarchical road network model and detailed algorithms are also illustrated in this paper. The proposed method can accelerate the process of generating and updating lane-level navigation information and can be an important component of a road marking information system for road management.  相似文献   

5.
Effective risk communication is central to good environmental risk management. While studies have shown that newspapers are the primary source of information to the public regarding environmental issues, little is known about how environmental news is used as a risk‐communication tool. This article explores the role of local information systems in risk communication, using newspaper content analysis as well as in‐depth interviews with journalists and community residents to develop a case study of an environmental assessment process for a nonhazardous industrial‐waste landfill. Results indicate that risk messages were chosen and shaped by journalists on the basis of their own exigencies. In addition, while newspapers were a major source of risk information, their impact was mitigated by resident distrust and access to other information sources, most notably their own personal information networks. These results have implications for environmental policy, as decision makers often use—either passively or actively—print media as a risk‐communication tool.  相似文献   

6.
摄影测量三维重建中多源信息融合方法探讨   总被引:1,自引:0,他引:1  
分析摄影测量三维重建中不同数据源的特点,针对现有多源数据融合存在的有限数据源低层次融合问题,提出一种基于影像特征、GIS信息和3D TIN模型融合的层次结构与算法流程 .该算法主要包括多边形区域增长、几何推理和建筑物几何模型平差等处理,为基于摄影测 量的三维城市模型自动重建提供了一种新的思路与方法.  相似文献   

7.
多源信息的集成与融合及其在遥感制图中的优化利用   总被引:13,自引:3,他引:13  
多源信息的集成和融合是地球信息科学领域的一大热点问题。它的意义和必要性与地球信息本身的特征、采集信息的手段特征及信息处理平台或系统的特点三方面紧密相联系。本文从不同传感器信息的集成和融合、遥感信息与非遥感地学信息的集成和融合、不同格式的 GIS数据的集成和复合三个方面研究了多源信息集成和融合的方法、前沿技术和应用领域,进而以黄土高原土壤侵蚀遥感调查和制图任务为例,介绍了多源信息集成和融合技术在该项目中的优化应用实例,包括技术流程分析、信息源分析、多源信息在土壤侵蚀遥感调查和制图中的融合方法、从遥感图像解译信息到 GIS数据库的转换技术等。  相似文献   

8.
基于信息流的互联网信息空间网络分析   总被引:4,自引:2,他引:2  
王宁宁  陈锐  赵宇 《地理研究》2016,35(1):137-147
信息化、网络化和全球化不断扩展加深了信息要素对于区域发展的作用,因此基于信息要素视角下的信息空间研究有助于政府管理部门为信息化发展和信息产业的布局提供科学的决策。从信息流的角度出发,建立了基于互联网信息流要素的信息空间测度方法,采用复杂网络分析方法深入探讨区域信息空间的格局和分布特征。研究发现,信息空间呈现“异质”发展趋势,省份的信息影响力呈现“东—中—西”三层递减态势。国家发展战略对信息空间的格局分布具有一定的影响作用。中东部省份中,北京、上海和广东省连接了中国南北以及东部地区,形成稳定的“三角格局”,现阶段中国的信息空间格局并没有完全脱离地理空间的制约,在一定程度上依然部分依赖于地域分布。  相似文献   

9.
翟青  甄峰  陈映雪 《地理科学》2015,35(10):1265-1271
信息技术对城市空间结构的影响一直是地理学关注的话题。随着信息技术的革新及其在社会生活中的普及应用,地理学者开始将研究视角从空间转向网络用户。引入信息科学领域的“地理关联”概念,通过南京居民问卷调查获得973个样本数据,采用结构方程模型分析,尝试从微观个体角度探索基于居民个体的虚-实空间的关联指标。结果发现:居民信息化程度、居民信息化认知、居民信息化习惯、居民流动性是微观层面虚-实空间关联的主要指标;居民流动性是空间关联最重要的衡量指标,其次是居民信息化认知、居民信息化习惯、居民信息化程度;工作地是最能展示网络空间与实体空间紧密关联的场所类型。  相似文献   

10.
Generally, multiple variables are sampled in addition to the one used to quantify the main phenomenon under study. In some situations, this secondary information is sampled exhaustively for the study area and can be incorporated for helping in estimating the variable of interest. There are several methodologies available for incorporating densely sampled secondary information. Collocated cokriging is one of these methodologies and has the advantage to other methodologies, of accounting for spatial correlation. However, one drawback in its application comes from the difficulty in modeling the coregionalization. Simplified models of coregionalization were developed specifically for the collocated cokriging case. This paper presents, through a case study, the incorporation of dense secondary information using collocated cokriging. The watertable above a coal underground mine is mapped using water-level readings at monitoring piezometers complemented by highly correlated topographic data. The incorporation of dense secondary information through the utilization of a linear model of coregionalization and Markov models is comparatively evaluated in various aspects such as mathematical quality, coherence with the natural phenomena and the ease of utilization and modeling. Simple kriging with local varying means also is evaluated as it accounts for nonstationarity and is easily implemented. All these methods that incorporate topography as secondary information for mapping the watertable provided maps more in accordance with the natural phenomena than ordinary kriging using the principal attribute solely. Among these methods, strictly collocated cokriging using a linear model of coregionalization showed overall superior performance.  相似文献   

11.
This article explores the notion of a system of ontologies specifically designed for the needs of an information science. A framework for geographic information ontologies is outlined that focuses on geographic information constructs rather than on the direct representation of real-world entities or on linguistic terms. The framework takes the form of a generative hierarchy anchored by the notion of intentionality at one end and of a spatiotemporal field of potentially relevant information at the other. Two theoretical notions are used in the generation of the hierarchy. The first is the principle of semantic contraction, whereby, starting from a level of geographic information constructs specified so as to reflect user intentionality, semantically coherent domains of properties are removed over several steps until only the rudiments of a spatiotemporal information system are left. The second notion is that of object of discourse, which allows entities to be represented as the composites of geographic information constructs at the higher levels of the hierarchy, explicitly reflecting the connections between the purpose, function, appropriate internal constitution, and ensuing categorization of the entities represented. The framework's main contribution is thus twofold: first, it allows the notions of user purpose and object function to be directly built into geographic representations; second, it proposes a hierarchy of ontological levels that are linked by systematic semantic relations. Further, the framework presents an integrated view of object and field representations. It may also provide a novel perspective on a number of issues of ongoing interest in geographic information science.  相似文献   

12.
泥石流信息范畴与信息收集   总被引:6,自引:0,他引:6  
谢洪  钟敦伦  韦方强  李泳 《地理科学》2000,20(5):474-477
泥石流及其灾害信息和与之有关的各种其它信息,都属于泥石流信息范畴。泥石流信息收集、整理及其标准化,是建立泥石流信息系统和实现信息资源共享与综合利用的基础。  相似文献   

13.
The rapid development of information and communication technologies (ICTs) has provided rich data sources for analyzing, modeling, and interpreting human mobility patterns. This paper contributes to this research area by developing the Spatio-temporal Edit Distance measure, an extended algorithm to determine the similarity between user trajectories based on call detailed records (CDRs). We improve the traditional Edit Distance algorithm by incorporating both spatial and temporal information into the cost functions. The extended algorithm can preserve both space and time information from string-formatted CDR data. The novel method is applied to a large data set from Northeast China in order to test its effectiveness. Three types of analyses are presented for scenarios with and without the effect of time: (1) Edit Distance with spatial information; (2) Edit Distance with time as a factor in the cost function; and (3) Edit Distance with time as a constraint in partitioning trajectories. The outcomes of this research contribute to both methodological and empirical perspectives. The extended algorithm performs well for measuring low-resolution tracking information in CDRs, as well as facilitating the interpretation of user mobility patterns in the age of instant access.  相似文献   

14.
基于地理实体的面向对象矢量模型设计   总被引:1,自引:0,他引:1  
空间数据模型是GIS实现地理空间数据组织、表达、分析、处理和应用的基础。针对基于要素的地理实体矢量描述方法的不足,从地理空间信息一体化管理角度,提出面向对象矢量模型(OOVM),探讨模型体系结构、空间对象的描述方法和空间数据管理模式。该模型利用面向对象的技术,将地理实体抽象为不同的空间对象,并将各空间对象的标识符、属性与方法封装在一起,便于网络环境下地理空间信息的存储和分布式管理。以公司信息管理为例,设计了基于OOVM的分布式空间数据组织过程,为空间数据库的建设和数据共享提供新的方法和思路。  相似文献   

15.
The map is a medium for recording geographical information. The information contents of a map are of interest to spatial information scientists. In this paper, existing quantitative measures for map information are evaluated. It is pointed out that these are only measures for statistical information and some sort of topological information. However, these measures have not taken into consideration the spaces occupied by map symbols and the spatial distribution of these symbols. As a result, a set of new quantitative measures is proposed, for metric information, topological information and thematic information. An experimental evaluation is also conducted. Results show that the metric information is more meaningful than statistical information, and the new index for topological information is more meaningful than the existing one. It is also found that the new measure for thematic information is useful in practice.  相似文献   

16.
Abstract

Practitioners and academics from many fields of study are currently facing numerous issues involving the diffusion of technologies from geographical information systems within their respective professions. This paper has two aims. The first is to report the partial results of a postal survey of selected municipal planning departments in the U.S.A. In measuring trends related to the adoption of computer and geographical information system technologies, the survey focuses on the availability of trained geographical information system and computer literate staff and on alternative means of training existing staff, as well as on the adequacy of collegiate education. The presentation of survey results is used to establish a framework for the principal discussion of this paper. The second part examines the relationship between planning and education in geographical information systems. Parallels within other disciplines and professions are derived. Curricula and training considerations within academic programmes and professional practice are suggested.  相似文献   

17.
Abstract

Attempts have been made by different organizations in India to organize data in order to develop a suitable information system. These attempts were oriented towards specific uses, such as natural resources, data management, thematic mapping and the like. In some attempts software has been developed for some specific purpose. It is not an easy task to develop an information system for a country such as India. Its extent in latitude and longitude is well above average. There are federal and state agencies for the collection of data and the preparation of maps. The geographical information concerning India is available from the following sources: the administrative areas of states, union territories, districts, sub-districts and villages; survey sheets; remote sensing images; aerial photographs; and thematic base maps of the National Atlas and Thematic Mapping Organisation. There are other map series available which have been used for socio-economic mapping. By the end of 1987 the Indian Remote Sensing Satellite will be launched and then remotely-sensed data will be readily available. Considering the geographical bases available in the country, five levels can be identified for developing an information system for India. Some of the thematic maps at 1:1000 000 scale can be used for initiating such a geographical information system.  相似文献   

18.
Abstract

Many data structures are possible for the storage of topological information for computer-based maps. The PAN graph is here suggested as an aid in the selection of a strategy appropriate to the application. Examples are given for the mapping of triangular networks and Thiessen polygons. Application of the technique is appropriate to both education in, and design of, spatial data structures for automated cartography and geographical information systems  相似文献   

19.
数字流域及其在流域综合管理中的应用   总被引:8,自引:1,他引:8  
流域的治理需要从系统的角度出发 ,综合考虑流域的自然、经济和社会子系统 ,实行综合管理。本文从新近发展起来的数字地球的概念出发 ,建立了数字流域的基本模式 ,初步探讨了数字流域的数据采集、处理、集成、显示及其在流域综合管理中的应用。  相似文献   

20.
The limitations of existing information sources on mergers/acquisitions within the EU are a serious obstacle to the study of the restructuring of the European production system. The experience of using a computerized abstracting service as a source of information on mergers/acquisitions in the chemical industry is reviewed. This experience informs an assessment of the strengths and weaknesses of similar databases as information sources in economic geography. The proliferation of such databases, together with advances in text management software, suggests that their potential has not been fully appreciated. This potential is considerable in providing easy access to detailed factual information on economic events and processes at continental and global scales. It is, however, strictly limited when it comes to interpreting the corporate strategies and motivations responsible for these developments.  相似文献   

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