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181.
Trevor Ward Steven Cork Kirstin Dobbs Peter Harper Peter Harris Tom Hatton 《Journal of Environmental Planning and Management》2015,58(4):738-755
A new approach was developed for Australia's 2011 national State of the Environment (SoE) report to integrate the assessment of biophysical and human elements of the environment. A Common Assessment and Reporting Framework (CARF) guided design and implementation, responding to jurisdictional complexity, outstanding natural diversity and ecosystem values, high levels of cultural and heritage diversity, and a paucity of national-scale data. The CARF provided a transparent response to the need for an independent, robust and evidence-based national SoE report. We conclude that this framework will be effective for subsequent national SoE assessments and other integrated national-scale assessments in data-poor regions. 相似文献
182.
为分析当今反恐新形势下的危险品运输网络优化设计问题的研究现状,系统总结国内外关于一般场景和恐怖袭击威胁2种情况下危险品运输网络优化设计研究的主要模型和方法,梳理两者现有的研究内容,并讨论其共性及恐怖袭击威胁情景下的研究的新特点。结果发现:目前关于解决危险品运输网络优化设计问题模型的鲁棒性研究较为缺乏,尤其是模型在更为复杂和不确定性更强的恐怖袭击情景中适用性不强;危险品运输的鲁棒优化模型即使在突发事件条件下,也可以使决策者能够作出相对满意的决策;鲁棒性危险品运输网络能够规避风险扰动,可用来防止在恐怖袭击中因危险品车辆爆炸等造成更大的危害。 相似文献
183.
Evaluating Alternative Temporal Survey Designs for Monitoring Wetland Area and Detecting Changes Over Time in California 下载免费PDF全文
Leila G. Lackey Eric D. Stein 《Journal of the American Water Resources Association》2015,51(2):388-399
Evaluation of wetland extent and changes in extent is a foundation of many wetland monitoring and assessment programs. Probabilistic sampling and mapping provides a cost‐effective alternative to comprehensive mapping for large geographic areas. One unresolved challenge for probabilistic or design‐based approaches is how best to monitor both status (e.g., extent at a single point in time) and trends (e.g., changes in extent over time) within a single monitoring program. Existing wetland status and trends (S&T) monitoring programs employ fixed sampling locations; however, theoretical evaluation and limited implementation in other landscape monitoring areas suggest that alternative designs could increase statistical efficiency and overall accuracy. In particular, designs that employ both fixed and nonfixed sampling locations (alternately termed permanent and temporary samples), termed sampling with partial replacement (SPR), are considered to efficiently and effectively balance monitoring current status with detection of trends. This study utilized simulated sampling to assess the performance of fixed sampling locations, SPR, and strictly nonfixed designs for monitoring wetland S&T over time. Modeled changes in wetland density over time were used as inputs for sampling simulations. In contrast to previous evaluations of SPR, the results of this study support the use of a fixed sampling design and show that SPR may underestimate both S&T. 相似文献
184.
基于BP神经网络优化制备Cu-Ce/TiO_2及其光催化活性研究 总被引:1,自引:1,他引:0
采用Cu和Ce对TiO2进行改性,基于正交实验设计和BP神经网络研究了Cu-Ce/TiO2中Cu-Ce对TiO2的摩尔百分数、Cu-Ce/TiO2中CuCe摩尔比及Cu-Ce/TiO2烧结温度对Cu-Ce/TiO2光催化降解甲醛溶液性能的影响.同时,对Cu-Ce/TiO2制备方案进行了优化,并运用X射线衍射仪、扫描电子显微镜和紫外-可见分光光度计对最佳条件下制备的Cu-Ce/TiO2进行表征.结果表明,优化的制备条件为Cu-Ce/TiO2中Cu-Ce对TiO2的摩尔百分数为2.88%,Cu-Ce/TiO2中Cu-Ce的摩尔比为1∶1,Cu-Ce/TiO2的烧结温度为570℃.共掺杂Cu离子和Ce离子能有效避免掺杂TiO2晶格内部表层和近表层产生较多的位错,从而抑制晶格畸变增大;诱导TiO2中锐钛矿型晶体向金红石型晶体转变的能力增强,有效抑制电子-空穴对的复合,产生介电局域效应. 相似文献
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Cost-efficient sample designs for collection of ground data and accurate mapping of variables are required to monitor natural
resources and environmental and ecological systems. In this study, a sample design and mapping method was developed by integrating
stratification, model updating, and cokriging with Landsat Thematic Mapper (TM) imagery. This method is based on the spatial
autocorrelation of variables and the spatial cross-correlation among them. It can lead to sample designs with variable grid
spacing, where sampling distances between plots vary depending on spatial variability of the variables from location to location.
This has potential cost-efficiencies in terms of sample design and mapping. This method is also applicable for mapping in
the case in which no ground data can be collected in some parts of a study area because of the high cost. The method was validated
in a case study in which a ground and vegetation cover factor was sampled and mapped for monitoring soil erosion. The results
showed that when the sample obtained with three strata using the developed method was used for sampling and mapping the cover
factor, the sampling cost was greatly decreased, although the error of the map was slightly increased compared to that without
stratification; that is, the sample cost-efficiency quantified by the product of cost and error was greatly increased. The
increase of cost-efficiency was more obvious when the cover factor values of the plots within the no-significant-change stratum
were updated by a model developed using the previous observations instead of remeasuring them in the field. 相似文献
188.
某钢铁企业高炉炼铁车间的出铁场在生产过程中产生大量高浓度的烟尘,对厂区的大气环境及周边的环境造成严重污染,同时直接危害了职工的身体健康。通过对整个出铁场除尘工艺系统及通风状况的分析及实际应用情况,总结出了适合该场合的系统除尘方案。 相似文献
189.
190.
本文介绍了基于任务成功率的装备综合保障工作体系框架,提出了可靠性、维修性、测试性、保障性、安全性协同设计环境要求,从而为进行可靠性、维修性、测试性、保障性、安全性综合优化设计奠定基础。 相似文献