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391.
鲁西北棉花雹灾损失监测信息系统研究   总被引:2,自引:1,他引:2  
鲁西北是我国最主要的产棉区,但棉花生长受雹灾影响频繁,致使棉花产量和质量下降,甚至局部绝产.本文对建立棉花雹灾损失监测信息系统的技术方法进行了探讨,包括棉花分布遥感调查、雹灾径迹雷达监测、数据库建立和棉花雹灾损失分析等,并给出了应用实例.  相似文献   
392.
针对环境监测管理信息平台的开发与应用,介绍了环境监测管理信息平台和开发,探讨了环境监测信息平台的主要功能,主要包括环境监测的人员管理、仪器设备管理、标准物质管理和质控管理,介绍了环境监测信息平台系统的特点,主要是环境监测的信息收集和利用、智能化预警机制、方便的信息查询,提出了环境监测平台实施中的探讨,如环境监测的前期设计和沟通、数据初始化和数据动态更新.  相似文献   
393.
The production and storage of dangerous substances in an industrial establishment creates risks for man, environment and properties in the surrounding area. Safety regulations require the establishment of a preventive information campaign regarding industrial risks and self-defence measures to adopt in an emergency situation. In the case of a major accident, people must be promptly made aware of the appropriate self-defence actions and behaviours to adopt. This strategic activity can reduce the panic effect, make citizens more cooperative and guarantee the effectiveness of any emergency plan. In this paper, the information chain is studied as an industrial process modelled by the IDEF0 language. Through this method, each link in the chain has been deeply analysed. For each function of the process, the inputs, outputs and necessary controls and resources have been identified. Starting from a clear view of the current state, the process of re-engineering has been implemented to minimise or eliminate downtime, deficiencies and illnesses and, thus, consequent time losses. The main contribution of the IDEF0 application in emergency management is to provide a clear view of the whole system, a communication system between emergency actors, a rich information source and a structured base for the re-engineering process.  相似文献   
394.
Y. Li  B. Chen  Z.F. Yang   《Ecological modelling》2009,220(22):3163-3173
Ecological network analysis (ENA) is introduced in this paper as a promising approach to study water use systems. Information indices from ENA involving total system throughput (TST), ascendency and overhead are calculated here. Two related aspects including organization inherent in system structures and synthesized water use intensity related with sustainable development of water use systems are analyzed. The indices of ascendency and overhead are applied for analyzing and characterizing water use network organization. For comparison of sustainability of water use systems from integrated aspects of environment, society and economy and based on TST, a new indicator termed as total system throughput intensity (TSTI) is constructed incorporating parameters of land, precipitation, population, GDP and environmental flow, which can be used as a measure of sustainability in terms of synthesized water use intensity. The Yellow River Basin in China during 1998–2006 is chosen as the case study and divided into subsystems according to the six river sections as from source to Lanzhou (S1-L1), Lanzhou to Toudaoguai (L1-T), Toudaoguai to Longmen (T-L2), Longmen to Sanmenxia (L2-S2), Sanmenxia to Huayuankou (S2-H) and Huayuankou to the mouth of Bo Sea (H-B). The results show that (i) the organization levels of L1-T and H-B are better than those of S1-L1 and T-L2, with those of L2-S2 and S2-H the worst; (ii) the synthesized water use intensity has been improving, of which T-L2, L2-S2 and S2-H are at the highest levels while H-B the lowest. In addition, the comparison between TSTI and other metrics and the relationship between ascendency and TSTI are discussed, from which the importance of TSTI is reflected and the optimization criterions for sustainable development of six subsystems are derived. It can be concluded that the application of ENA in water use systems can provide new angles for water resource management to address the challenges of assessing and optimizing options to obtain more sustainable water use.  相似文献   
395.
Aquatic biogeochemical models are widely used as tools for understanding aquatic ecosystems and predicting their response to various stimuli (e.g., nutrient loading, toxic substances, climate change). Due to the complexity of these systems, such models are often elaborate and include a large number of estimated parameters. However, correspondingly large data sets are rarely available for calibration purposes, leading to models that may be overfit and possess reduced predictive capabilities. We apply, for the first time, information-theoretic model-selection techniques to a set of spatially explicit (1D) algal dynamics models of varying parameter dimension. We demonstrate that increases in complexity tend to produce a better model fit to calibration data, but beyond a certain degree of complexity the benefits of adding parameters are diminished (the risk of overfitting becomes greater). The particular approach taken here is computationally expensive, but several suggestions are made as to how multimodel methods may practically be extended to more sophisticated models.  相似文献   
396.
环境决策与信息支持   总被引:13,自引:0,他引:13  
科学的决策过程包括发现问题、确定目标、确定价值准则、拟定方案、分析评估、方案优选和实施等过程。环境决策是涉及经济、社会、资源、环境之间关系的综合性问题;是一个多变量、多层次、多目标的复杂大系统问题,需要大量的信息支持。良好的环境信息系统要将环境决策过程与信息过程有机地结合起来。当前我国环境信息系统网络的建设应该加强统一规划和管理。   相似文献   
397.
基于国内环境监测行业信息化建设的现状,针对SaaS模式在该领域的应用做可行性分析。介绍了SaaS模式与传统ASP模式的区别,探讨了SaaS模式给环境监测信息化建设带来的选择与机遇,以及其满足各层次多用户需求、实现服务个性化定制、具备快速扩展和恢复能力等优势。结合现阶段环境监测信息化建设采用SaaS模式在政策体制、业务实现、信息技术方面所面临的问题,提出了相应的建议。  相似文献   
398.
介绍了江苏省太湖流域水环境信息共享平台建设在环境信息交换、三维展示、联机分析处理、数据挖掘等关键技术的应用,以解决制约环境信息化共享的瓶颈。探索环境信息集成共享、多维展示、综合分析的设计思路和发展方向,以推动环境管理的现代化。  相似文献   
399.
对我国环境自动监测发展的思考   总被引:6,自引:16,他引:6       下载免费PDF全文
阐述了我国环境自动监测的现状,指出环境自动监测的发展势头迅猛异常,国产自动监测仪器设备的发展前景广阔,而仪器设备标准化和监测系统规范化问题比较突出,建议自动监测系统的建设发展速度适度控制,重视自动监测信息建设与数据共享问题,加强监控管理,理顺管理体制和运行机制.  相似文献   
400.
根据珠江三角洲空气污染特征.将,SO2、NO2、PM10、O3四项参数作为评价指标,对建立区域空气质量指数(Regional Air Quality Index,RAQI)~型及区域空气质量分级方法,以及开展区域空气质量信息发布的空间表征技术进行了研究,以便直观有效地反映珠江三角洲区域空气质量状况.  相似文献   
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