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241.
Economic theory asserts that to achieve maximum conservation benefits land acquisition needs to be cost effective. Yet the most common planning technique used by land conservation organizations is ‘benefit-targeting’ that focuses only on acquiring parcels with the highest benefits and ignores costs. Unlike most of the literature which focuses on covering problems, this research applies optimization techniques to achieve maximum aggregate conservation benefits for an ongoing land acquisition effort in the Catoctin Mountain Region in central Maryland. For this case study, optimization yields additional conservation benefits worth an estimated $3.1–$3.9 million or achieves the same level of conservation benefits but at a cost savings ranging from $0.9 to $3.5 million, depending on the initial budget size. Finally, the highest efficiencies are achieved in low budget scenarios, like those most prevalent in conservation efforts. 相似文献
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Identification of electricity energy consumption on individual household appliances used in a smart house is the first important step for making the use and conservation of electricity energy more efficient. In the past, Non-Intrusive Load Monitoring (NILM) techniques, which are part of smart grid techniques realized to improve electricity energy usage efficiency, have been developed to identify individual appliances with avoiding installing many smart meters for appliances in a field. In this paper, a new NILM technique that integrates an efficient Genetic Programming (GP)-based feature optimizer with pattern recognition techniques is proposed to identify which appliance is being turned on or off. The proposed GP-based feature optimizer with Fisher criterion is used to generate a more efficient feature than original potential transient features extracted from captured transient response of household appliances through analysis of NILM. The new feature generated by GP is used by pattern recognition techniques as load identifiers for load identification. The load identifiers used and compared in this paper include k-Nearest-Neighbor Rule, Back-Propagation Artificial Neural Network, and Learning Vector Quantization. Experiments are conducted under different single-load and multiple-load operation circumstances at different actual experimental environments with small disturbances. As shown from the experimental results, the proposed is confirmed to be feasible and usable. 相似文献
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Child‐ and youth‐friendly spaces have become a common feature of emergency humanitarian provision. This study reports on the outcomes of child and youth learning centres (CYLCs) in Ethiopia's Buramino Camp established for those fleeing conflict in Somalia. Eighty‐five youths completed baseline assessments shortly after arrival and follow‐up assessments three to six months later. Caregivers of 106 younger children completed similar appraisals. 693 children attending the CYLCs completed pre‐ and post‐educational assessments, which indicated major gains—significant at p<0.0001—in both literacy (younger children, t=9.06; youth, t=13.87) and numeracy (younger children, t=13.94; youths, t=17.10). Children's CYLC attendance increased reports of met needs among caregivers (t=2.53, p<0.05) and youths (t=2.57, p<0.05), and, among caregivers but not youths, significantly moderated protection concerns (t=2.39, p<0.05, and t=?1.90, p=0.06, respectively). There was general improvement in psychosocial well‐being over time for all children; CYLC attendance predicted greater reductions in reported difficulties only among younger children (t=2.51, p<0.05). 相似文献
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Mathematical models used to optimize the process plant layout (PPL) with risk reduction have four primary objectives, which are related to the minimization of land, pumping (pipe system), protection system devices, and risk costs. Moreover, these models are of two types: continuous plane models (CPM) and grid-based models (GBM); however, the nonconvexity of the CPM models makes difficult to achieve the global optimum, because it is formulated as Mixed-Integer Nonlinear Programming (MINLP). Thus, the risk map approach has been implemented with the grid-based models to solve problems of process plant layout focused on finding the best possible solution. However, these risk map formulations present important limitations, mainly related with the use of protection devices and the occupied area. Therefore, a new GBM-MILP formulation is proposed to optimize the selection of protection devices and minimize the occupied area. The risk is reduced through the investment on safety devices instead of considering the increase of separation distances. The proposed model was used to solve the layout problem of an ethylene oxide process, and the results was compared with a process layout reported in the literature. The results show that the model can provide the best possible solution; however, the time spent in the calculation is considerably greater than that reported for continuous plane models. Finally, the model can be used by decision-makers to evaluate different layout options for several explosion scenarios, during the early stages of the plant design. 相似文献
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高速公路交通应急救援资源的配置 总被引:1,自引:0,他引:1
针对交通事故与救援资源存在随机性的特点,建立了交通救援资源配置的随机模型。根据高速公路特有的道路条件与交通机理,确定了模型中救援服务水平、事故概率的权重,配置点至事故点的权值以及随机资源等参数值。将所建立的模型与参数用于河南省高速公路的救援资源配置,研究表明,新的配置方案较好满足了交通事故高概率区域的救援需求,并且合理减少了救援需求区域的资源配置数量,为目前高速公路交通应急资源的科学配置提供了重要的参考依据。 相似文献
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为在突发性自然灾害发生后的黄金救援时间内,使各应急物资调配中心的物资在最短时间内高效地运往各受灾点,最大程度地平衡受灾程度不同的受灾点群众对应急物资救援的心理满意度,构建以应急物资救援时间最短为目标的上层模型;通过借鉴前景理论量化受灾群众的心理满意度,在考虑各受灾点对有限应急物资存在竞争关系的基础上,建立下层非合作博弈模型;设计遗传算法求解上层模型、改进粒子群算法求解下层模型的层次混合算法。结果表明:构建的多应急物资调配中心多受灾点的非线性整数双层规划模型,使应急物资的调配具有时效性,且更加客观地衡量各灾点物资调配的公平合理性,该模型为应急物资调配研究提供借鉴与参考。 相似文献
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随着城市化进程的推进,每年都有大量的火灾事故发生,造成大量的人员伤亡和财产损失,为了避免事故发生或者减少伤亡损失,火灾风险评估是一种有效的方法之一。基于层次分析法,提出了对数模糊优先规划法进行火灾风险评估。首先以地下车库火灾风险评估为例,参考相关文献和专家意见,建立了地下车库火灾风险评价指标体系;然后利用对数模糊优先规划法计算各个评价指标的权重,然后根据专家打分获得评语集,结果所计算的权重集,可以得到地下车库的火灾风险评估结果为"良好"。最后,进行讨论了火灾风险评估的方法的有效性,并与层次分析法对比,对数模糊优先规划法可以使得决策者更加自信和舒适,并且决策结果更加合理。 相似文献