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751.
752.
Evaluating the Impacts of Environmental Flow Alternatives on Reservoir and Recreational Operations Using System Dynamics Modeling
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Ryan R. Morrison Mark C. Stone 《Journal of the American Water Resources Association》2015,51(1):33-46
Providing environmental flows is increasingly a management obligation in many water resource systems. Evaluating the impacts of environmental flow alternatives on other water uses in a basin can be a challenge, especially when collaborating with stakeholders. We demonstrate the use of system dynamics (SD) modeling to assess the impacts of four environmental flow alternatives in the Rio Chama, New Mexico. The model was developed to examine impacts of each alternative on reservoir storage and releases, hydropower production and revenue, and whitewater boating access. We simulated each alternative within a stochastic framework in order to explicitly incorporate hydrologic uncertainty into the analyses. The environmental flow alternatives were developed at a collaborative workshop of geomorphology, hydrology, and ecology experts. Results from the model indicate that the proposed flow recommendations on the Rio Chama will generally decrease annual reservoir storage, increase median flows, and have minimal impacts on hydropower production and whitewater rafting on the system. The Rio Chama case study is a promising example of how SD modeling can be used in the early stages of environmental flow studies and why it is compatible with collaborative modeling. 相似文献
753.
People,protected areas and ecosystem services: a qualitative and quantitative analysis of local people's perception and preferences in Côte d'Ivoire
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Ariane Amin Julie G. Zaehringer Gudrun Schwilch Inza Koné 《Natural resources forum》2015,39(2):97-109
The long‐term integrity of protected areas (PAs), and hence the maintenance of related ecosystem services (ES), are dependent on the support of local people. In the present study, local people's perceptions of ecosystem services from PAs and factors that govern local preferences for PAs are assessed. Fourteen study villages were randomly selected from three different protected forest areas and one control site along the southern coast of Côte d'Ivoire. Data was collected through a mixed‐method approach, including qualitative semi‐structured interviews and a household survey based on hypothetical choice scenarios. Local people's perceptions of ecosystem service provision was decrypted through qualitative content analysis, while the relation between people's preferences and potential factors that affect preferences were analyzed through multinomial models. This study shows that rural villagers do perceive a number of different ecosystem services as benefits from PAs in Côte d'Ivoire. The results based on quantitative data also suggest that local preferences for PAs and related ecosystem services are driven by PAs' management rules, age, and people's dependence on natural resources. 相似文献
754.
为了有效监测电网作业人员不规范佩戴安全帽行为,提出1种基于YOLOv3的电网作业现场安全帽佩戴检测方法.针对安全帽佩戴规范性问题,构建正确佩戴、不正确佩戴和未佩戴安全帽3种情况下的图像样本库;并利用该数据库对YOLOv3模型进行训练与测试,结合模型参数、样本比例及算法对比分析,开展电网作业人员安全帽佩戴检测算例.结果表... 相似文献
755.
Zhengheng Pu Jieru Yan Lei Chen Zhirong Li Wenchong Tian Tao Tao Kunlun Xin 《Frontiers of Environmental Science & Engineering》2023,17(2):22
756.
The 27th of March 2003, an explosion caused the death of four employees in a Nitrochimie pyrotechnic plant, at Billy Berclau, in the north of France. Following the accident, the ministry of Ecology and Sustainable Development appointed INERIS to perform an investigation. According to the terms of reference, the investigation would cover technical (origins of the explosion, extent of damages) as well as organisational issues, as defined by SEVESO II safety management system requirements. This paper has a threefold purpose. It intends first to illustrate with an empirical case the current trend in safety auditing and accident investigation, targeting organisational factors, alongside human factors. There are not so many published cases of accidents analysed with an organisational perspective. Secondly, it shows that it is possible to investigate organisational dimensions (through articulation of safety engineering, safety management and human and social sciences) within reasonable time frames and a reasonable amount of resources. By focusing on key actors and asking appropriate questions related to key dimensions, investigating organisational accidents might not necessarily imply spending much more resources than other steps such as damage assessment, chronological construction or identification of technical scenarios, although there are also some prerequisite conditions needed to achieve this. Finally this paper should be seen as a technical communication beyond the pyrotechnic industry. 相似文献
757.
Earthquakes are a major cause of displacement, particularly in developing countries. Models of injury and displacement can be applied to assist governments and aid organisations in effectively targeting preparedness and relief efforts. A stratified cluster survey was conducted in January 2008 to evaluate risk factors for injury and displacement following the 15 August 2007 earthquake in southern Peru. In statistical modelling, seismic intensity, distance to rupture, living conditions, and educational attainment collectively explained 54.9 per cent of the variability in displacement rates across clusters. Living conditions was a particularly significant predictor of injury and displacement, indicating a strong relationship between risk and socioeconomic status. Contrary to expectations, urban, periurban, and rural clusters did not exhibit significantly different injury and displacement rates. Proxies of socioeconomic status, particularly the living conditions index score, proved relevant in explaining displacement, likely due to unmeasured aspects of housing construction practices and building materials. 相似文献
758.
利用Matlab软件及Office组件函数编写了基于宏观经济指标进行地震灾害快速评估并自动生成灾害简报的程序。该程序可以充分利用天津地区高密度强震台网资源,也可以计算理论烈度下的灾害评估结果。程序利用的基础数据资料主要是乡镇级别的人口及区县级别的GDP统计数据,数据更新维护经济可靠。通过与天津市"十五"地震应急评估系统触发的342个地震灾害评估结果对比,表明二者之间相关性非常强,而该程序计算速度则快一个量级以上。程序涉及的数据处理及计算方法适合于大城市及城市群的地震灾害快速评估。 相似文献
759.
北京市水资源数据管理系统 总被引:6,自引:0,他引:6
介绍了《北京市水资源数据管理系统》的概况,以水资源、环境与社会经济活动信息为基础,采用计算机技术建立包括社会经济活动、水资源开发、城市排水、水污染环境质量等各类信息的具有空间特征的水资源宏观数据管理体系,并为政府有关部门提供可靠的决策依据。 相似文献
760.
流动注射化学发光测定痕量亚硝酸根的研究 总被引:3,自引:0,他引:3
基于NO_2~-对I_2-EDTA光化学反应的抑制作用和I_2与鲁米诺的化学发光反应,建立了痕量亚硝酸根的流动注射化学发光分析方法.试验并选择了最佳条件,测定了天然水中亚硝酸根的含量,回收率在93—103.5%,方法线性范围为1.0×10~(-7)—4.0×10~(-6)mol.L~(-1),检测限为1.1×10~(-6)mol.L~(-1).对2.0×10~(-7)mol·L~(-1)NO_2~-进行测定,相对标准偏差为2.2%. 相似文献