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1.
为有效降低灾后初期应急资源短缺情况下灾民生理和心理受到的伤害,提出等待效应和短缺效应衡量救援过程中的灾民心理痛苦效应,同时耦合时间和供需情况2个维度测度救援过程中的公平性指标,构建调度总时间最短、时间攀比最小和灾民心理痛苦效应最低的多目标应急资源调配模型,研究多灾点、多配送中心、多种类物资救援场景下的应急资源分配和路径规划决策选择问题。应用NSGA-Ⅱ算法对模型求解,以新冠疫情下武汉市医疗物资调度为算例分析验证模型的有效性。结果表明:模型和算法能有效减少供不应求情况下的灾民心理痛苦效应,保证救援活动的公平性,能得到不同目标偏好下的应急资源调配方案。 相似文献
2.
Joslin L. Moore Abbey E. Camaclang Alana L. Moore Cindy E. Hauser Michael C. Runge Victor Picheny Libby Rumpff 《Conservation biology》2021,35(5):1639-1649
Land managers decide how to allocate resources among multiple threats that can be addressed through multiple possible actions. Additionally, these actions vary in feasibility, effectiveness, and cost. We sought to provide a way to optimize resource allocation to address multiple threats when multiple management options are available, including mutually exclusive options. Formulating the decision as a combinatorial optimization problem, our framework takes as inputs the expected impact and cost of each threat for each action (including do nothing) and for each overall budget identifies the optimal action to take for each threat. We compared the optimal solution to an easy to calculate greedy algorithm approximation and a variety of plausible ranking schemes. We applied the framework to management of multiple introduced plant species in Australian alpine areas. We developed a model of invasion to predict the expected impact in 50 years for each species-action combination that accounted for each species’ current invasion state (absent, localized, widespread); arrival probability; spread rate; impact, if present, of each species; and management effectiveness of each species-action combination. We found that the recommended action for a threat changed with budget; there was no single optimal management action for each species; and considering more than one candidate action can substantially increase the management plan's overall efficiency. The approximate solution (solution ranked by marginal cost-effectiveness) performed well when the budget matched the cost of the prioritized actions, indicating that this approach would be effective if the budget was set as part of the prioritization process. The ranking schemes varied in performance, and achieving a close to optimal solution was not guaranteed. Global sensitivity analysis revealed a threat's expected impact and, to a lesser extent, management effectiveness were the most influential parameters, emphasizing the need to focus research and monitoring efforts on their quantification. 相似文献
3.
Alexander L. Metcalf Conor N. Phelan Cassandra Pallai Michael Norton Ben Yuhas James C. Finley Allyson Muth 《Conservation biology》2019,33(5):1141-1150
Widespread human action and behavior change is needed to achieve many conservation goals. Doing so at the requisite scale and pace will require the efficient delivery of outreach campaigns. Conservation gains will be greatest when efforts are directed toward places of high conservation value (or need) and tailored to critical actors. Recent strategic conservation planning has relied primarily on spatial assessments of biophysical attributes, largely ignoring the human dimensions. Elsewhere, marketers, political campaigns, and others use microtargeting—predictive analytics of big data—to identify people most likely to respond positively to particular messages or interventions. Conservationists have not yet widely capitalized on these techniques. To investigate the effectiveness of microtargeting to improve conservation, we developed a propensity model to predict restoration behavior among 203,645 private landowners in a 5,200,000 ha study area in the Chesapeake Bay Watershed (U.S.A.). To isolate the additional value microtargeting may offer beyond geospatial prioritization, we analyzed a new high-resolution land-cover data set and cadastral data to identify private owners of riparian areas needing restoration. Subsequently, we developed and evaluated a restoration propensity model based on a database of landowners who had conducted restoration in the past and those who had not (n = 4978). Model validation in a parallel database (n = 4989) showed owners with the highest scorers for propensity to conduct restoration (i.e., top decile) were over twice as likely as average landowners to have conducted restoration (135%). These results demonstrate that microtargeting techniques can dramatically increase the efficiency and efficacy of conservation programs, above and beyond the advances offered by biophysical prioritizations alone, as well as facilitate more robust research of many social–ecological systems. 相似文献
4.
排污权初始分配是排污权交易的起点和基础,在分配模式和实证研究方面需要加强。采用地区人口法、经济总量法、历史排污量法、环境容量法和综合分配法5种模式研究了鄱阳湖流域11个地市水污染物化学需氧量(COD)与氨氮的初始排污权分配。结果表明:COD和氨氮初始排污权在地市之间的分配格局相似;南昌、新余与鹰潭3市按经济总量模式分配的排污量明显高于其它模式,上饶、吉安两市人口分配模式高于其它模式,景德镇、九江两市历史排污量模式高于其它模式,赣州市环境容量模式高于其它模式,宜春市综合模式高于其它模式。综合分配模式为赣州市排污权总量最高,南昌、九江、吉安、宜春、抚州和上饶6市次之,景德镇、萍乡、新余、鹰潭4市最低。总体来看,排污权配额因分配模式不同而有所差异,综合分配模式得到的初始排污权最为合理。建议鄱阳湖流域严格执行综合分配模式下的各地市初始排污权分配额度,确保区域经济社会与生态环境的协调发展。 相似文献
5.
Water Transactions for Streamflow Restoration,Water Supply Reliability,and Rural Economic Vitality in the Western United States 下载免费PDF全文
Eloise Kendy Bruce Aylward Laura S. Ziemer Brian D. Richter Bonnie G. Colby Theodore E. Grantham Leslie Sanchez Will B. Dicharry Emily M. Powell Season Martin Peter W. Culp Leon F. Szeptycki Carrie V. Kappel 《Journal of the American Water Resources Association》2018,54(2):487-504
Across the western United States, environmental water transaction programs (EWTPs) restore environmental flows by acquiring water rights and incentivizing changes in water management. These programs have evolved over several decades, expanding from relatively simple two‐party transactions to multiobjective deals that simultaneously benefit the environment and multiple water‐using sectors. Such programs now represent an important water management tool and provide an impetus for collaboration among stakeholders; yet, most evaluations of their effectiveness focus exclusively on environmental outcomes, without adequate attention to impacts on other water users or local economies. To understand how these programs affect stakeholders, a systematic, multiobjective evaluation framework is needed. To meet this need, we developed a suite of environmental and socioeconomic indicators that can guide the design and track the implementation of water transaction portfolios, and we applied them to existing EWTPs in Oregon and Nevada. Application of the indicators quantifies impacts and helps practitioners design water transaction portfolios that avoid unintended consequences and generate mutually beneficial outcomes among environmental, agricultural, and municipal interests. 相似文献
6.
为了解决平视显示器(Head Up Display,HUD)飞行中的注意资源分配问题,基于飞行模拟器,设计双作业飞行任务开展相关研究。基于事件相关电位(Event Related Potential,ERP)技术,选取行为绩效和P300成分为评价指标,采用oddball模式,在双作业飞行任务条件下开展实验研究。结果表明:随主任务难度的增加,主、辅任务的作业绩效均显著下降,被试者对HUD上异常信息的正确操作率降低,且反应时间延长;随主任务难度的增加,由辅任务所诱发的P300的波幅显著降低。在实验结果的基础上,最终提出了HUD状态下飞行员视觉注意资源分配机制。 相似文献
8.
Manoj Roy Robin Curry Geraint Ellis 《Journal of Environmental Planning and Management》2015,58(10):1749-1769
Studies of urban metabolism provide important insights for environmental management of cities, but are not widely used in planning practice due to a mismatch of data scale and coverage. This paper introduces the Spatial Allocation of Material Flow Analysis (SAMFA) model as a potential decision support tool aimed as a contribution to overcome some of these difficulties and describes its pilot use at the county level in the Republic of Ireland. The results suggest that SAMFA is capable of identifying hotspots of higher material and energy use to support targeted planning initiatives, while its ability to visualise different policy scenarios supports more effective multi-stakeholder engagement. The paper evaluates this pilot use and sets out how this model can act as an analytical platform for the industrial ecology–spatial planning nexus. 相似文献
9.
10.
从资源的视角而言,水资源具有的社会、经济、生态属性中,社会属性和生态属性所提供的生态功能和服务多是外部性和非市场的,其价值在纯粹的市场驱动下难以充分实现。从资源管理视角而言,水资源多目标协同配置的实质是水资源多重属性功能和服务的均衡。因此,将具有外部性的社会、生态功能和服务与具有经济价值的功能和服务同时纳入配置框架,是实现多目标协同配置实践的关键问题。本文在回顾水资源配置和水资源非市场价值评估的相关研究的基础上,围绕我国现行水资源配置存在的主要问题,通过水资源的全价值(市场价值和非市场价值)将其多属性功能和公众意愿纳入水资源多目标协同配置中,从水资源管理信息系统、全价值评估和配置管理的绩效评价三个方面构建了水资源配置的多目标协同框架,最后提出相关的保障政策建议。 相似文献