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61.
国民信息素养的高低已成为一个国家在全球竞争中获得优势地位的关键,信息素养教育在全世界范围内备受重视。本文以信息素养为出发点,以当今高校对在校大学生信息素养培训的新要求为依据,通过信息的选择、检索、利用,个人创新和文化素养等五个方面的教育,论述了如何培养高校学生信息素养,使学生养成终身学习的习惯。  相似文献   
62.
电袋复合除尘器的应用研究   总被引:1,自引:0,他引:1  
针对我国燃煤电厂的除尘现状,指出电袋复合除尘器的技术经济优势.电袋复合除尘器在新建及改扩建电厂的成功应用取得了良好的经济、环境效益,并有广阔的发展前景.其研究重点是静电除尘单元和布袋除尘单元之间的结合.  相似文献   
63.
Land managers need better techniques to assess exoticplant invasions. We used the cross-correlationstatistic, I YZ, to test for the presence ofspatial cross-correlation between pair-wisecombinations of soil characteristics, topographicvariables, plant species richness, and cover ofvascular plants in a 754 ha study site in RockyMountain National Park, Colorado, U.S.A. Using 25 largeplots (1000 m2) in five vegetation types, 8 of 12variables showed significant spatial cross-correlationwith at least one other variable, while 6 of 12variables showed significant spatial auto-correlation. Elevation and slope showed significant spatialcross-correlation with all variables except percentcover of native and exotic species. Percent cover ofnative species had significant spatialcross-correlations with soil variables, but not withexotic species. This was probably because of thepatchy distributions of vegetation types in the studyarea. At a finer resolution, using data from ten1 m2 subplots within each of the 1000 m2 plots, allvariables showed significant spatial auto- andcross-correlation. Large-plot sampling was moreaffected by topographic factors than speciesdistribution patterns, while with finer resolutionsampling, the opposite was true. However, thestatistically and biologically significant spatialcorrelation of native and exotic species could only bedetected with finer resolution sampling. We foundexotic plant species invading areas with high nativeplant richness and cover, and in fertile soils high innitrogen, silt, and clay. Spatial auto- andcross-correlation statistics, along with theintegration of remotely sensed data and geographicinformation systems, are powerful new tools forevaluating the patterns and distribution of native andexotic plant species in relation to landscape structure.  相似文献   
64.
The degree at which tropical forests are exposed to human pressure is spatially dependent. Population density, proximity to roads, terrain slope, logging activities and land distribution projects are well known factors inducing deforestation and forest degradation in Latin America. Using expert knowledge to weight these threat factors and a Geographical Information System for spatial modeling, a multi-criteria analysis procedure is presented, that allows stratifying a study region in categories of deforestation threat. The procedure was implemented in the Central Volcanic Mountain Range Conservation Area (CVMRCA) in Costa Rica with the purpose of finding areas with a combination of physical and socioeconomic characteristics that is particularly predisposing to a high probability of deforestation. To validate the map, the CVMRCA was stratified in categories of deforestation risk, and the result was superposed to historical deforestation data of the period 1986–1996. The good correlation between risk category and historical deforestation (r = 0.91, p < 0.001) indicates that the map can be used as a decision support tool for defining priority areas for conservation action.  相似文献   
65.
冲压机械伤害风险评价信息系统研究   总被引:1,自引:1,他引:0  
研究冲压机械伤害风险评价信息系统,无论对企业内部事故预防还是对职工健康安全,还是节省国家因事故造成的经济损失,都十分必要。应用计算机编程语言和数据库软件,对冲压作业进行综合管理评价、设备设施的固有危险性评价及劳动卫生与作业环境评价,进而对冲压作业风险进行评价分级,建立动态的冲压机械伤害风险评价数据库管理信息系统。该系统可保存所有评价的项目资料,供应用和参考,实现了对冲压机械伤害风险评价的数据库动态管理,使风险评价分析工作组织化、条理化、系统化。  相似文献   
66.
油气集输站安全监控预警及管理信息系统的开发   总被引:4,自引:1,他引:3  
提出油气集输站安全监控预警及管理信息系统建设的调研内容、需求分析以及安全相关控制系统的风险分析流程。设计了该系统建设的4层结构框架和拓扑图,深入研究了实时参数监控、分级报警与安全保护控制、智能诊断与预警、多媒体监控、安全生产管理信息子系统的主要开发内容和功能实现。  相似文献   
67.
This work aims at evaluating spatial distribution patterns of concentration variations for chlorinated solvents in groundwater, based on principal component analysis and geographic information system (GIS) tools. The study investigates long-time series of chlorinated solvent concentrations in groundwater measured for 18 contaminated industrial sites. The characterization of contaminant plumes and delineation of pollutant sources are essential for choosing appropriate monitoring and remediation strategies, as contaminated groundwaters are characterized by complex patterns of spatial and temporal concentration variability, with wide unpredictable fluctuations over time. The present work describes the results of a new exploratory statistical method called the Variability Index Method (VIM) applied to environmental data to assess the performance of using concentration variations as molecular tracers to reveal aquifer dynamics, industrial impacts, and point sources for contamination plumes. The application of this method provides a useful assessment of controls over contaminant concentration variations as well as support for remediation techniques.  相似文献   
68.
Enhancing community-based disaster preparedness with information technology   总被引:1,自引:0,他引:1  
A critical component of community-based disaster preparedness (CBDP) is a local resource database of suppliers providing physical, information and human resources for use in disaster response. Maintenance of such a database can become a collaborative responsibility among community-based non-governmental organisations (NGOs) and public and private community organisations. In addition to mobilising resources, this process raises awareness within the community and aids in assessing local knowledge and resources. This paper presents the results of a pilot study on implementing a community-based resource database through collaboration with local American Red Cross chapters and public and private community organisations. The design of the resource database is described. The resource database is accessible via the internet and offline using laptops and handheld Personal Digital Assistants. The study concludes that CBDP is strengthened through a combination of appropriate information technology and collaborative relationships between NGOs and community-based organisations.  相似文献   
69.
建设项目竣工环境保护验收监测应注意的问题   总被引:1,自引:0,他引:1  
针对建设项目竣工环境保护验收监测中存在的问题,阐述了工况控制、总量监测、环境相容性等环节的技术要求和注意事项,并就与之相关的公众参与、监测人员的素质等问题展开了讨论。  相似文献   
70.
基于现代信息技术的城市灾害应急管理系统   总被引:6,自引:0,他引:6  
城市灾害应急管理系统是一项复杂的大系统工程。本文着重从应急管理过程中的应急资源调配、应急预案制定等方面阐述了现代信息技术在城市灾害应急管理中的应用与优势。认为应急管理信息系统的建立目的不是为了预测和估算,而应是当灾害发生时,对已造成的灾情局面做出快速的辅助决策支持。基于此,利用SuperMapObject5.0,Visual Basic6.0,SQL Server2000等现代信息技术软件,以辅助决策、资源快速查询以及生命线管网易损处调查为目的,本文建立了一个局部地区灾害应急管理信息系统。系统的数据库建立更突出了为应急管理服务所需的基础信息、空间数据、应急预案和应急资源等信息划分方式;结合已有的震害预测理论和方法,开发了供水系统和交通系统的震害预测模块,事先为灾害应急决策提供可能的震害信息。系统的开发过程进一步证明了GIS在城市灾害应急管理中有着直观显示、容易操作、辅助准确决策等优势。  相似文献   
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