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排序方式: 共有1915条查询结果,搜索用时 15 毫秒
1.
The effect of mountain relief and industrial air pollution on biometric parameters of pine stands was studied. The empirical–statistical models of the dependence of biometric characteristics on the parameters of forest sites were developed using raster modeling and multivariate analysis. The possibility of predicting changes in the biometric parameters at any site on the basis of these models is shown.  相似文献   
2.
Marincioni F 《Disasters》2007,31(4):459-476
A comparative survey of a diverse sample of 96 US and Italian emergency management agencies shows that the diffusion of new information technologies (IT) has transformed disaster communications. Although these technologies permit access to and the dissemination of massive amounts of disaster information with unprecedented speed and efficiency, barriers rooted in the various professional cultures still hinder the sharing of disaster knowledge. To be effective the available IT must be attuned to the unique settings and professional cultures of the local emergency management communities. Findings show that available technology, context, professional culture and interaction are key factors that affect the knowledge transfer process. Cultural filters appear to influence emergency managers' perceptions of their own professional roles, their vision of the applicability of technology to social issues, and their perspective on the transferability of disaster knowledge. Four cultural approaches to the application of IT to disaster communications are defined: technocentric; geographic,; anthropocentric; and ecocentric.  相似文献   
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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   
5.
This paper discusses the relationship of new information and communication technologies (ICTs) and sustainable development. It deconstructs popular myths about a sustainable information society. One myth is that telework has reduced the need to travel and hence environmental pollution. The reality is that teleworkers make up only a small share of the total workforce, telework can generate new social relationships and hence the need for more travelling, work-related travel produces only a small amount of the total carbon dioxide emissions, and that the total distance travelled per employee is constantly rising. Another myth is that information economy is weightless and dematerialized which reduces environmental impacts. The energy and resource intensities of the ICT sector are indeed lower than the one of the total economy. The ICT sector also emits less CO2 than the total economy. But the ICT sector constitutes only a small portion of the total value added and fossil fuel combustion is still the dominant activity of modern industrial economies. Some stakeholders argue that virtual products allow resource, energy, and transport savings. But burning digital music on compact discs and DVDs, printing digital articles and books, etc. results in rebound effects that cause new material and energy impacts, computers have a low life span of 2–3 years, reusable and upgradeable computers and computer equipment are hardly used and might not be as profitable as non-reusable ones, computers are consuming much energy. Alternatives such as energy consumption labels on ICTs and green ICTs that consume less energy contradict dominant economic interests. A sustainable information society is a society that makes use of ICTs and knowledge for fostering a good life for all human beings of current and future generations by strengthening biological diversity, technological usability, economic wealth for all, political participation of all, and cultural wisdom. Achieving a sustainable information society costs, it demands a conscious reduction of profits by not investing in the future of capital, but the future of humans, society, and nature.  相似文献   
6.
基于腔衰减相移光谱法设计了一套二氧化氮在线分析仪,通过优化测量参数,该仪器可长期稳定运行,其时间分辨率为60 s,检出限为0.191 ppb,在0~300 ppb范围内,NO2气体浓度与相位正切信号值具有较好的二次拟合关系,R2为0.9995.另外,该仪器在泰安站进行了长期外场观测,并与改装后的进口商品化仪器PKU-Thermo 42i-TL进行比对实验,结果表明,两者的测量结果一致性较好,R2=0.9811,表明其具有良好的运行稳定性和测定结果准确性,适用于环境大气二氧化氮浓度的在线监测.外场观测结果表明,春季泰安站二氧化氮浓度均值为12.39 ppb,有明显日变化规律.  相似文献   
7.
大尺度空间(中国)化学品环境暴露多介质模型的建立需要先对空间做相应的区划.本文以ArcGIS软件为平台,通过有空间约束的聚类方法和水文分析方法相耦合,建立全国范围的综合分区.全国范围分为华南综合大区、华北综合大区、西北综合大区、华东综合大区、东北综合大区和西南综合大区6个综合大区.每个综合大区又分别包含了若干个综合小区,小区总数为38个.该研究为我国暴露评估的综合分区提供了一个方案,在多介质模型的建立中起着重要的作用.  相似文献   
8.
简述了实验室信息管理系统(LIMS)的概念和建设LIMS的现实意义,着重介绍了上海市环境监测中心实施LIMS的过程和体会,分析了环境监测实验室在LIMS选型和实施过程中需要注意的问题及LIMS对现行工作的影响,并对需进一步完善的功能提出了建议.  相似文献   
9.
本文阐述了高等院校教育技术的发展现状,分析了高等院校教育技术发展的特点,对高等院校教育技术的发展进行理性思考。认为高等院校应该在重视教育技术实践性和支持性研究的基础上,立足现实,更全面审视机构整合、教育信息化、信息资源库建设和教师培训这些热点问题。  相似文献   
10.
REMIS is one of key research projects sponsored by the central government. It is recommended to regional EPAs as a main tool of the environmental management. REMIS simulates the functions of the regional EPAs and aimed to improve their management level. The national environmental management information system will base on REMIS.Functional analysis is the kernel of the REMIS system analysis. Data and data flow analysis are used to support the functional analysis.Investigations on the functions of the local EPAs of eight provinces and 12 cities have been taken. The functions were carefully sorted. Modular design method was used in system analysis and system design.The system analysis included functional analysis, data analysis and data flow analysis. The system design is based on the system analysis. HIPO diagram of each modular, data base structure, menu design, selection of hardware and software environment were the main items of the system design.  相似文献   
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