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531.
为了对输变电工程中的大量资料进行信息化动态管理,对电磁环境参数进行预测分析,为电网决策、管理、运行提供依据,建立电网环境保护信息管理系统。阐述系统的构建、实现及运用Matlab工具进行电磁环境参数预测模型的求解,通过系统集成完成信息管理和预测分析模型系统的开发,实现电网环境保护的决策分析。以可听噪声预测模型构建为例,在C#.NET平台上调用Matlab工具箱,实现了输电线路可听噪声的预测分析。  相似文献   
532.
Howell NL  Rifai HS  Koenig L 《Chemosphere》2011,83(6):873-881
PCDD/F and PCB field data (1041 samples) in five media (dissolved, suspended sediment, bed sediment, catfish, and blue crab) were studied to explore dual contaminant patterns in the Houston Ship Channel, Texas, USA. PCDD/Fs showed greater concentration than PCBs in suspended sediments while PCBs were higher in apparent dissolved (truly dissolved + DOC-associated), fish, and crab. PCDD/Fs at nearly all locations contributed more strongly to dioxin-like toxicity. The fraction of PCB TEQ was, however, enriched in biotic over abiotic media due in large part to the presence of PCB 126, which was mostly undetected in water and sediment and yet exhibited a BAF three times greater than 2,3,7,8-TCDD. Dissolved-suspended sediment and suspended-bed sediment relationships showed that (1) observed apparent dissolved concentration differences (as fraction of total water were mean 10% PCDD/Fs and 63% PCBs) can reasonably be explained by a four-phase partition model (truly dissolved, DOC-associated, suspended OC, and suspended BC) for PCBs but not for PCDD/Fs and (2) the contaminants behaved similarly in bed to suspended sediment concentration ratios (Cbed/Csusp) upstream of a major confluence but not downstream. PCA-cluster analysis pointed to the possibility that suspended sediment PCB contamination originates from resuspended bed sediment while PCDD/Fs in suspended sediment originates more probably from other sediment sources such as upstream wash load or air deposition. Finally, examinations of a congener marker ratio (PCB 209/206) seemed to indicate that a source of pure PCB 209 may exist in bed sediment near Patrick Bayou though the source was not completely localized.  相似文献   
533.
To assess changes in human understanding and decision making, the paper examines (1) the influence of visual information on perceptions about groundwater management in Phoenix, Arizona and (2) the correlates and dimensions underlying people's views about water scarcity and mitigation strategies. While perceptions entrenched in ideologies are difficult to change, different types of information (three-dimensional versus two-dimensional) have distinct impacts on the perceived magnitude of problems compared to judgements about their causes and solutions. Overall, visual information may be especially useful for developing a shared understanding of problems and a collective vision for management alternatives. Additional implications of this study for fostering environmental awareness, policy support, and collaborative decision making are also discussed.  相似文献   
534.
环境科学数字图书馆信息资源建设中的著作权问题   总被引:1,自引:0,他引:1  
针对数字图书馆信息资源建设中面临的著作权问题,依照著作权法等相关法律,分析了环境科学数字图书馆建设中涉及到的实体馆藏文献数字化、虚拟馆藏等著作权问题,并提出了完善相关法律、加强著作权集体管理体制、建立图书馆版权联盟等对策与措施。  相似文献   
535.
The ever-increasing complexity of disasters demands utilisation of knowledge that exists outside domains traditionally drawn upon in disaster management. To be operationally useful, such knowledge must he extracted, combined with information generated by the disaster itself, and transformed into actionable knowledge. The process, though, is hampered by existing, business-oriented approaches to knowledge management, by technical issues related to access to relevant, multi-domain information/knowledge, and by executive decision-making processes based predominantly on historical knowledge. Consequently, as shown by many recent incidents, the management of large-scale (mega) disasters is often inefficient and exceedingly costly. This paper demonstrates that the integration of modified information and knowledge management into the concepts of network-centric operations and network-enabled capabilities, and the employment of Boyd's OODA (Observe, Orient, Decide, and Act) Loop-based decision-making in unpredictable and dynamically changing environments, may address some of these problems.  相似文献   
536.
生态文明是社会主义文明的组成部分之一,是社会文明发展的新阶段.生态文明使有关图书的重要性更加突出,数量激增,涉及的范围更加广泛,类型更加复杂多样.因此,图书管理应以生态文明为指导,为生态文明建设服务,采取高度重视,调整、增加分类,开设专柜、专室,及时向读者提供有关信息等措施.  相似文献   
537.
Abstract: Land use in a watershed is commonly held to exert a strong influence on trunk channel form and process. Land use changes act over human time‐scales, which are short enough to measure effects on channels directly using historic aerial photographs. We show that high‐resolution topographic surveys for the channels of paired watersheds in the Lehigh Valley, Pennsylvania, are comparable, but have channel widths that have changed dramatically in the past five decades. The two watersheds, Little Lehigh Creek and Sacony Creek, are similar in most aspects except in their respective amount of urban land use. Aerial photographs of the urbanized Little Lehigh Creek show that a majority of the measured widths (67 of 85) were statistically wider in 1999 than in 1947. In contrast, the measured widths from the agricultural Sacony Creek are more evenly distributed among those that widened (18), narrowed (28), and those that were statistically unchanged (6) from 1946 to 1999. From 1946 to 1999 the only section of Sacony Creek that widened was that reach downstream of the only sizable urban area in the watershed. The current land use in Sacony Creek watershed resembles that of 1946, while the Little Lehigh Creek watershed has more than tripled its urban area. These data, in concert with other recent hydrologic data from the watersheds suggest that the increase in urban area‐generated peak discharges is the mechanism behind the widening that occurred in the Little Lehigh Creek. These wider channels can affect water quality, aquatic habitat, suspended sediment loads, and river esthetics.  相似文献   
538.
运用data system.exe技术,提出大气环境影响评价信息可视化软件的设计方法,建立了大气环境污染因子数据信息可视化模型,应用该成果对某石油化工企业大气环境进行初步风险评价,结果表明:通过输入大气环境污染因子监测值,系统可自动判定大气环境的污染程度,并把对应环境质量的级别、环境的安全程度以及污染对人体与生物的影响程度在图中显示出来,能有效地提高环境影响评价的可靠度。该软件能在识别污染因子数据信息的同时生成与之相匹配的直观的模拟环境图像,有助于管理者进行及时分析与决策,建立的环境污染因子数据信息可视化软件具有很强的适用性。同时对政府部门制定环保工作决策具有重要的参考价值。  相似文献   
539.
现代企业安全管理信息系统的构建   总被引:2,自引:0,他引:2  
论述现代企业安全管理信息系统的功能需求、基本框架、核心功能和系统特点。该系统把信息技术、网络技术及GIS应用到企业安全管理中,并融入安全学习志的管理理念,同时对基于联动机制的企业安全应急决策系统综合理论及其应用进行了研究。通过该系统的建立,使安全管理工作逐步走向科学化、系统化和规范化,对提高目前安全管理水平具有实际意义。  相似文献   
540.
泥石流灾害风险评价方法及其应用研究   总被引:3,自引:2,他引:1  
探讨泥石流灾害风险评价的理论和方法;利用已有的泥石流灾害资料,建立泥石流风险评价体系和实施流程;提出风险评价的定量计算方法;结合遥感和地理信息系统技术,完成了云南省昆明市东川区泥石流灾害的定量风险评价。研究结果与泥石流实际分布和调查资料基本一致,表明所提出的泥石流灾害风险评价的理论与方法具有一定的理论价值和现实意义,可以为泥石流灾害风险评价和防灾减灾管理提供有益的科学依据。  相似文献   
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