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1.
空间信息技术是防洪减灾现代化的基础 总被引:2,自引:5,他引:2
我国洪涝灾害频繁,洪灾损失严重,防洪减灾将是一项长期而艰巨的任务。在防洪减灾研究中,必须积极引进当今最新科学技术成果,以高新技术改造水利这一传统产业,以水利信息化推动水利现代化。以遥感、地理信息系统和全球导航定位系统为支撑的空间信息技术可以广泛地应用于防洪减灾中,是防洪减灾现代化的基础。本文分析了空间信息技术在防洪减灾中的作用,并对空间信息技术在防洪减灾中的应用趋势作出展望。 相似文献
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Field investigations indicate that unpaved roads are the largest sediment source on St John, US Virgin Islands. Cross-sectional measurements of eroded road surfaces were used to establish an empirical relationship to predict annual road surface erosion as a function of road gradient and contributing drainage area. A model (ROADMOD) for estimating and mapping average annual sediment production from a road network was developed by combining this empirical relationship with a series of network algorithms to analyse road data stored in a vector geographic information system. ROADMOD was used to estimate road surface erosion in two St John catchments with very different road densities but similar land cover, topography and soils. Unpaved roads were found to increase sediment production in the more densely roaded catchment by a factor of three to eight, and in the less-roaded catchment by a factor of 1·3–2·0. Turbidity measurements in the receiving bays of these two catchments are consistent with model predictions and observed sediment delivery processes. Although this model was developed specifically for St John, it can easily be adapted to other locations by substituting a locally derived predictive equation for road erosion. Model assumptions, limitations and potential improvements are discussed. © 1998 John Wiley & Sons, Ltd. 相似文献
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Thomas J. Pingel 《The Journal of geography》2018,117(4):153-164
Game-based Web sites and applications are changing the ways in which students learn the world map. In this study, a Web map-based digital learning tool was used as a study aid for a university-level geography course in order to examine the way in which global scale cognitive maps are constructed. A network analysis revealed that clicks were negatively correlated with familiarity, but were positively correlated with area. More significantly, well-known countries did not act as central nodes within network-based mental models, but served a more complex mediating role in structuring the space between subregions. 相似文献
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Firms often encounter location-based impediments that hinder them from engaging with international markets. These challenges can be exacerbated for smaller firms, which often have limited resources and exposure to global markets. This article examines successful small and medium-sized exporters from Nova Scotia, a province with decreased export activity in recent years. It explores these firms’ trade-related motivations, their impediments, and the strategies that they have used to address possible location-related problems. Although geographical distance does not appear to be a competitive challenge, other issues emerge, including travel expenditures and the costs of export intelligence gathering. Successful exporters have overcome many potential impediments by using government trade programs, establishing and maintaining face-to-face contacts, and working with international partners. 相似文献
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基于GIS的水资源管理信息系统 总被引:22,自引:0,他引:22
地理信息系统(GIS)因为其强大的空间数据处理能力,为水资源管理提供了一个新颖、高效的工具。本文深入GIS的功能和水资源管理的实际,通过山西汾阳县的应用实例,阐述了应用ArchInfo/ArcView构建水资源管理信息系统过程中的信息收集、储存、分析以及二次开发的方法和过程,分析了两者结合应用的可行性和优越性,并讨论了这种方法在水资源系统模拟、辅助决策支持等方面的广泛应用前景。 相似文献
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加强应急管理、有效应对突发事件是国家的一项重要工作,以地理空间信息技术为核心的应急管理地理信息平台建设,已成为目前国内省级应急平台建设的主要模式。本研究建立了应急联动一张图和地理信息应急服务总线,对省级应急资源多源、异构、动态、多时相信息整合技术难题进行探索,实现了地理信息服务与全市各级应急系统的业务融合。目前,研究成果已融入重庆市应急信息资源共享体系,在多个部门的应急业务系统中得到有效的集成应用,为形成全市应急资源全方面共享格局发挥了重要作用。 相似文献
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This study applies a TuPu analysis to investigate ecological and environmental aspects of an Antarctic ice-free area, using Fildes Peninsula as an example. The TuPu unit was determined using a vector-grid mixed data model. Information from the eco-environment elements was effectively extracted, and was generalized into different classes by means of data mining technol- ogy. A series of single-factor thematic information TuPu models, such as topography, soil, animal and vegetation, and human activities for Fildes Peninsula were built in this study. The topography TuPu model contained information on elevation and slope. The soil TuPu model involved soil development stages and soil thickness information. The animal and vegetation TuPu model contained the distribution of animals, plant types, lichen cover and lichen height. The human activities TuPu model included popu- lation density and human disturbance index information. The landscape comprehensive information TuPu model of Fildes Penin- sula also was established, and contains twenty-nine landscape units and twelve types of combined environments. The study quan- titatively revealed the spatial morphology and correlation of the regional eco-environment based on the analysis of these TuPu models. From these models, we can draw the conclusion that there is a regular differentiation of eco-environment from the coastal bands to the central hills in Fildes Peninsula, and that the eco-environment condition of the eastern coasts is different from that of the western coasts. The eco-environmental spatial variation also differs greatly from north to south. Based on analysis of spatial correlation, the vegetation in Fildes Peninsula has the greatest correlation with human activity, and has a certain correlation with topography and soil. This research may provide a new technical approach and scientific basis for the in-depth study of Antarctic eco-environments. 相似文献