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1.
Mapping technologies have made considerable strides in recent decades. Global positioning systems (GPS), remote sensing satellites, Web-based mapping services, and geographic information systems (GIS) have facilitated the collection, distribution, analysis, and ultimately interaction with geospatial information. In particular, portable GPS have altered how individuals participate in mapping. Individuals can use GPS to collect tracings of their personal interactions with the environment. These interactions can then be uploaded to one of many available Web-based mapping services. Once uploaded, the geospatial data can be mapped and shared among the broader community of users. Such volunteered geographic information (VGI) exemplifies the conceptualization of an individual collecting, mapping, and sharing personal geographic information. This paper focuses on challenges surrounding VGI. To help place these challenges in a broader context, specialized Web services and GPS technologies developed for the bicycling community will serve as examples of the current status and future prospects of VGI.  相似文献   

2.
Australia and New Zealand are adopting the Spatial Data Transfer Standard (SDTS) as their transfer standard for geographic data. The standard requires a number of modifications to suit Australia/New Zealand requirements. These modifications primarily involve coordinate reference systems for each country, references to those standards applicable to each country and new spatial feature dictionaries. For other countries adopting SDTS, future revisions to the standard should emphasize a framework for required modifications. Australia/New Zealand have established a support body to ensure the smooth introduction of the standard within these countries. This commercial venture has been successful in promoting the standard, in providing training and in related consulting work. The US Geological Survey has been the maintenance authority for the standard. It is essential that this function continues to be provided through this body to guarantee a single interpretation of the standard.  相似文献   

3.
The quality of dynamic map symbols plays an important role in the representation of spatial-temporal changes. This paper reports an investigation into the quality of dynamic symbols. To assess the quality of such symbols, a set of traffic flow data is used for the production of different kinds of dynamic maps, with focus on four variables, i.e. size, color, frame rate and display format. Two quantitative measures are used for analysis, i.e. deviation and response time. A set of traffic data is used for the production of dynamic maps for evaluation. The experimental results show that the size is more efficient and more effective than color for dynamic maps with the same frame rate and display format. The most efficient and effective color class number is 10 on the large format display such as 1024 × 768 pixels. And the most efficient and effective size class number is 15 on large format display such as 1024 × 768 pixels. The effective frame rate for dynamic map animation is smaller than that of the general animation on the Internet or Quick Time and AVI format video. The most efficient and most effective frame rate is 3 frames per second in the color expression and 6 frames per second in the size expression. In sum, the effective and efficient value of color, size and frame rate on large format display is less than the value on the small format display. These results suggest the frame rate should be reduced on the small format display. It is hoped that the results from this study will be of help in the design of effective and efficient dynamic map symbols for geographical information visualization.  相似文献   

4.
The TIGER System is many things to many people. At this juncture, the TIGER System has fulfilled the precensus geographic support functions for which the Geography Division designed it. During the next 18 months, the TIGER System will support a number of functions needed to complete the tabulation of the collected data and make those data useful to the numerous constituencies that carry out the myriad tasks that define our lives. Simultaneously with the use of the TIGER System to support the data tabulation and dissemination missions of the Census Bureau, work will be under way to define a framework for the future of this bold new product – and this future looks bright. If the TIGER System is to be judged truly useful outside the Census Bureau, similar planning will need to be going on in offices and institutions across America. This is true especially in the context of geographic information system (GIS) applications involving the digital products of the TIGER System and the demographic data products of the 1990 census.  相似文献   

5.
The increasing sophistication of classification techniques used in land use and land cover analysis has not been matched by attention to the origin and effects of land cover categories. While classifications appear unproblematic and self-evident, they carry with them their own histories, meanings and effects, which remain largely unexamined. In an effort at such scrutiny, we examine the origins of land cover categories deployed in remote sensing and conclude that categories are theory-laden metaphors and occur epistemologically prior to any clustering algorithm, no matter how sophisticated. We describe the problematic effects that the imposition of classification systems in place of in situ knowledge of the landscape can have, especially in a colonial or post-colonial context. As an alternative to imposed classification, we propose and demonstrate an empirical technique based upon a growing body of work in participatory GIS. The method compares image classifications based on local and expert knowledge, using a case study from Rajasthan, India, concluding that differing metaphors of landscape lead to divergent measures of land cover.  相似文献   

6.
Understanding the spatial dimension of fear of crime in the urban environment is important to understanding behaviors in response to this concern. Making this connection between perception and action has long been a goal of scholars in the social and health sciences, though this complex relationship has yet to be fully elucidated. Specifically, in studies on fear of crime and its influence on behavior, a variety of definitions and methods have been employed. This situation has yielded insights, as well as inconsistencies. In the past decade, Geographic Information Systems (GIS) has been added to this methodological mix, though it too has contributed limited understanding of the environmental perception-behavior nexus. During this time, some scholars have integrated a traditional technique for accessing environmental perception, the sketch map, with this newer technology. This article provides a review and critical assessment of the way GIS has been used to understand fear of crime, specifically through the integration of sketch maps. This focus is framed by an overview of substantive and methodological concerns and concludes with a discussion of continued research needs. As behavioral responses to fear of crime are acknowledged to impact physical and mental health and overall well-being, in addition to the viability of neighborhoods, research in this area will continue apace. However, for integration of sketch maps in GIS to be a valuable methodological contributor to this line of inquiry, users of the approach must understand its complexities. This article outlines these issues so that they may be considered in future research and may improve the ability for this approach to yield new understanding of fear of crime.  相似文献   

7.
8.
A number of decision support systems (DSS) were evaluated prior to commencing public participatory geographic information systems (PPGIS) workshops within a small rural town undergoing rapid development. A paucity of existing information regarding the capabilities of these tools and their utility in supporting various PPGIS applications was noted. In order to improve this situation and to better understand the strengths and limitations of the selected DSS CommunityViz, we monitored and measured its utility in supporting community-based spatial decision-making processes from both a technologist and citizen's perspective. Results indicate that CommunityViz has several strengths; however, the software exhibits some weaknesses in the context of our study. In assessing these results we realized that the utility of such findings could be much enhanced if contained within a structure that enables comparison between various DSS. Thus, a major objective was to develop and apply a DSS Evaluation Matrix (DSSEM) that can be used by PPGIS practitioners and participants to evaluate DSS in various project settings. The application of DSSEM will help formalize evaluations of DSS and encourage dissemination of results. Furthermore, it will assist practitioners, citizens, and agencies to make better choices when selecting DSS for PPGIS applications and provide DSS developers with the appropriate information to improve tool design.  相似文献   

9.
Abstract

Although the efficiency of label placement algorithms has been studied extensively, few studies considered the influence of the label designs on the efficiency of map readers. Labels are one of the most important elements on the map as they can provide more information than other symbols can. The design of the labels does have to stress the theme, shape and functionality of the associated objects, which results in a more efficient interpretation of the map content by the user. How the label designs can enhance the map readers’ efficiency (and thus the quality of the maps themselves) is the main objective of this study. A user study was conducted in which the participants were asked to locate a target label on a map. Different label designs were implemented across the trials. The participants’ reactions times were registered to measure their efficiency and statistically analysed using a one-way ANOVA. Two different users’ characteristics were considered: gender and expertise. Related to the size, shape, orientation and texture of the labels, a number of significant differences (P<0·05) and trends were located. Differences in efficiency between males and females, on the one hand, and between novices and experts, on the other hand, were also described statistically. Consequently, recommendations can be formulated regarding the design of labels in order to obtain more efficient maps, keeping in mind the map users’ characteristics.  相似文献   

10.
介绍了新疆维吾尔自治区安全生产监管地理信息平台中的重大危险源监管地理信息系统,详述了系统构架、系统组成、系统功能及主要作用。阐述了重大危险源监管地理信息系统是基于空间信息的安监专题信息处理、信息综合、信息分析、统一处置的地理信息系统。说明了重大危险源监管系统是一个高效的综合管理系统,体现地理信息系统与安全生产监督管理的高度结合,实现了重大危险源等各类监管对象的动态管理和重大事故应急指挥智能化。能够加强新疆安全生产的监管能力,提高事故的应急救援指挥和救援行为的效率,从而形成"信息畅通、反应快捷、指挥有力",集信息监管、救援、指挥于一体的新疆维吾尔自治区安全生产监管体系。  相似文献   

11.
加强测绘监管,维护国家基础地理信息安全   总被引:1,自引:0,他引:1  
龚德坤  于卫东 《北京测绘》2010,(3):87-88,83
基础地理信息已成为信息化战争的基础,加强测绘监管是维护国家安全的现实需要。本文介绍了基础地理信息在信息化战争的作用,分析了基础地理信息安全现状,并提出了加强测绘监管的具体建议。  相似文献   

12.
吴厚清 《测绘通报》2014,(8):120-124
在信息化时代背景下,测绘与地理信息行业面临新的机遇和挑战,同时公众对地理信息服务也提出了更高的要求。本文在详细剖析浙江省测绘与地理信息合作共建新模式的基础上,以公安、统计、突发性灾害的应用为例,结合国内地理信息服务的现状,提出了拓展测绘与地理信息服务新领域的几点思考与建议,旨在开创地理信息共建共享从基本业务合作向战略合作转变的新局面  相似文献   

13.
Crowdsourcing is a popular means of acquiring data, but the use of such data is limited by concerns with its quality. This is evident within cartography and geographical sciences more generally, with the quality of volunteered geographic information (VGI) recognized as a major challenge to address if the full potential of citizen sensing in mapping applications is to be realized. Here, a means to characterize the quality of volunteers, based only on the data they contribute, was used to explore issues connected with the quantity and quality of volunteers for attribute mapping. The focus was on data in the form of annotations or class labels provided by volunteers who visually interpreted an attribute, land cover, from a series of satellite sensor images. A latent class model was found to be able to provide accurate characterisations of the quality of volunteers in terms of the accuracy of their labelling, irrespective of the number of cases that they labelled. The accuracy with which a volunteer could be characterized tended to increase with the number of volunteers contributing but was typically good at all but small numbers of volunteers. Moreover, the ability to characterize volunteers in terms of the quality of their labelling could be used constructively. For example, volunteers could be ranked in terms of quality which could then be used to select a sub-set as input to a subsequent mapping task. This was particularly important as an identified subset of volunteers could undertake a task more accurately than when part of a larger group of volunteers. The results highlight that both the quantity and quality of volunteers need consideration and that the use of VGI may be enhanced through information on the quality of the volunteers derived entirely from the data provided without any additional information.  相似文献   

14.
大数据时代的到来给测绘地理信息档案带来了新的发展机遇。本文结合大数据和测绘地理信息档案的特点,对测绘地理信息档案资源进行了规划,并提出其应用的方向。  相似文献   

15.
增城市采用SOA的理念和方法,遵循OGC规范,利用WebService技术,构建了数字增城地理空间信息公共服务平台,实现了空间信息的互联互通,取得了良好的应用效益。  相似文献   

16.
以MapGIS地理信息平台为基础、以SQL SERVER2000数据库为后台,神农架林区松柏镇为研究对象,阐述了城镇地籍建库的方式、建库流程,再列举了在建库过程中遇到常见问题及解决方案,从而建成符合城镇地籍数据库标准MAPGIS地理信息平台的城镇地籍数据库成果。最后介绍了MapGIS地理信息平台的下数据库实现功能如地籍数据格式转换功能、图形与信息检索查询、ACESS数据导入与影像挂接、统计分析与成果输出、日常办公及查询统计等功能。  相似文献   

17.
目前,我国正处于城市人口剧增的城镇化加速发展时期,同时,也面对交通堵塞、环境污染、能源紧缺等来自各方面的挑战。那么,如何破解城市发展所带来的诸多难题,实现城市可持续发展呢?建设智慧城市已成为当今世界城市发展不可逆转的历史潮流。目前,我国已有154个城市提出建设智慧城市。然而,在智慧城市建设过程中出现了值得重视的问题,即一些城市对基础地理数据、空间信息以及基础地理信息共享平台的建设认识不明确,重视不够。搭建地理信息共享平台是智慧城市建设的基础,是城市转型发展、生态文明建设、新型城镇化和治理现代化的需求,是推进“互联网+”行动和促进电子政务协调发展等方面的要求。因此,必须按照先进性、现势性、完备性、实用性等原则搭建地理信息共享平台。  相似文献   

18.
建设基于Web GIS的旅游地理信息系统,是促进和推广GIS在旅游产业中应用的有效方法。根据牡丹江市旅游业发展实际和我国可使用的在线电子地图现状,从方便用户出发,设计并构建了基于天地图的牡丹江市旅游地理信息系统。该系统充分利用了空间数据库和GIS的空间查询和分析功能。本文对该系统进行了研究设计。该系统的搭建为建设牡丹江市旅游服务平台、发展牡丹江市旅游事业提供了技术支撑,为百姓出行旅游提供了辅助参考。  相似文献   

19.
招商、引资、发展是过去20年来巾国长江三角洲城市与珠江三角洲城市经济增长的一个主要策略,尤其是长、珠三角地区的经济发展上是一个主要的动力.以地理信息系统(GIS)的平台,呈现经过经济与管理实证的"引资环境"指标,就是一个相当有效的方法.文章报告<中国两大外向型经济区域引资发展环境统计指标图示集>的内容及如何进一步利用地理信息系统的想法.  相似文献   

20.
以浙江省省、市(县)联动更新工作(安吉县)为例,探索建立了对同一个地理实体对象基础地理信息只高精度采集一次的省、县基础地理信息数据联动更新模式,通过增量更新模式完成浙江省与安吉县基础地理信息数据的联动更新。  相似文献   

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