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851.
Uncertainty management in integrated assessment modeling: towards a pluralistic approach 总被引:4,自引:0,他引:4
Integrated Assessment (IA) is an evolving research community that aims to address complex societal issues through an interdisciplinary process. The most-widely used method in Integrated Assessment is modeling. The state of the art in Integrated Assessment modeling is described in this paper in terms of history, general features, classes of models, and in terms of the strengths and weaknesses, and the dilemmasand challenges modelers face. One of the key challenges is the issue of uncertainty management. The paper outlines the sources and types of uncertainty modelers are confronted with. It then discusses how uncertainties are currently managed inIntegrated Assessment modeling, on which evaluation it is argued that complementary methods are needed that allow for pluralistic uncertainty management. The paperfinalises with discussing pluralistic concepts and approaches that are currently explored in the IA community and that seem promising in view of the challenge to incorporate explicitly more than one hidden perspective in models. 相似文献
852.
853.
针对目前大型机载信息化系统的软件可靠性越来越重要,而传统可靠性鉴定试验无法考核系统软件可靠性,软件可靠性测试无法考核综合环境应力下的软件可靠性,以及软硬件一体化可靠性指标考核的问题,提出了大型机载信息化系统软硬件一体化可靠性鉴定试验方法解决这一问题的设想。该方法综合考虑了传统可靠性鉴定试验和软件可靠性测试的优点,并详细给出一种大型机载信息显示和控制系统的应用实例,充分地分析论证了该方法的可行性和科学性。 相似文献
854.
以传质理论和双层分阶段厌氧多生物相(TSMPA)理论为基础,设计了厌氧污泥-生物膜异波折板复合式反应器,进行为期12个月的生活污水处理中试研究.动态试验结果表明,在温度为25℃±2℃条件下,系统的最佳水力停留时间(HRT)为6 h.此时所对应的COD、TP、TN去除率分别为78.58%、 35.15%、 39.17%;最适厌氧污泥区百分比为45%~65%.HRT为6 h,温度降至7℃时所对应的COD、TP、TN去除率分别为64.37%、 20.72%、 23.65%;最大比甲烷产率为1.85 mL/(g·h).结果表明,在北方地区低温条件下应用本技术处理低浓度生活污水可行. 相似文献
855.
Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China. In this study, sandwich hybridization integrated with nuclease protection assay (NPA-SH) was used to qualitatively and quantitatively detect P. globosa. Results showed that this method had good applicability and validity in analyzing the samples from laboratory cultures and from fields. The linear regression equation for P. globosa was obtained, and the lowest detection number of cells was 1.8 × 104 cells. Statistics showed that there was no distinct difference between the results of detecting the microalgae by NPA-SH and traditional microscopy. This technique has good reliability, accuracy, and can give a remarkably high sample processing rate. Sandwich hybridization integrated with nuclease protection assay will provide an efficient alternative to microscopic method for monitoring and investigating the bloom of P. globosa. 相似文献
856.
Malone TC 《Environmental monitoring and assessment》2003,81(1-3):51-62
The combined effects of human activities and natural variability present significant challenges to the goals of protecting, restoring, and sustaining coastal ecosystems. Meeting these challenges and resolving conflicts in an informed fashion will require: (1) more timely detection and prediction of environmental changes and their consequences; and (2) more timely access to relevant environmental information. The achievement of these goals depends on the development of a sustained and integrated coastal ocean observing system (ICOOS) that insures timely access to the data and information required to improve: (1) climate predictions and the effects of changes in the weather on coastal populations; (2) efforts to sustain and restore healthy coastal marine ecosystems and living marine resources; and (3) compliance monitoring and evaluations of the efficacy of environmental policies. Although the responsible federal and state agencies all require similar environmental information, many separate programs have evolved for collecting, managing, and analyzing data for various purposes. Consequently, there is too much redundancy; access to diverse data from disparate sources is limited and time consuming; and individual programs are inevitably underfunded and too limited in scope. A system is needed that coordinates and integrates many of the elements of these programs to minimize redundancy, be more comprehensive, provide more timely access to data and information, and satisfy the information needs of a greater number of user groups in a more cost-effective fashion. This is the purpose of the ICOOS. 相似文献
857.
介绍了砀山县近期处理规模为25000m^3/d、采用一体化氧化沟工艺的污水处理厂的设计情况,并针对雨污合流制采取了一系列的解决措施。 相似文献
858.
基于Web GIS的饮用水水质监控系统,利用Internet/Intranet技术、GIS技术、数据库技术和环境保护技术,建立了完善的水污染监测与管理网络体系,实现了水源地污染空间信息、属性信息的综合管理.首先介绍了此系统的需求目标,进一步阐述了系统的体系结构、数据库设计和主要功能. 相似文献
859.
张子炎 《安全.健康和环境》2020,(4):12-18
采用ALOHA软件对典型化学品的池火灾及BLEVE事故进行了模拟计算,分析了事故的危害范围情况。BLEVE火球热辐射的危害范围比池火大,烃类化学品发生事故的影响比其他类别化学品严重;化学品的碳链越长,危害越大;含有硝基的化学品危害范围最小。分析结果可以作为预测数据,为典型化学品泄漏事故救援提供有效的技术支持。 相似文献
860.
基于结构功能指标体系评价法,利用层次分析法构建锦州湾海域生态系统健康评价指标体系,并选择2005—2009年8月生态调查数据对其进行初步的定量评价。结果表明,可以通过海洋化学指标、生态学指标和社会经济学指标三大类33个指标来建立锦州湾生态系统健康评价指标体系;2005—2009年8月锦州湾生态系统的整合健康指数依次分别为1.01、1.90、2.00、1.45和1.10,均低于系统健康指数值2,锦州湾海域生态系统连续5年一直处于亚健康状态,且从目前海域的污染现状来看,这一海域的水质、沉积物和生物体污染均比较严重,要修复其生态功能需要投入巨大的物质和能量。 相似文献