针对现有配电网鲁棒调度方法缺乏对不确定参数相关性问题的考虑,提出了一种基于数据驱动多面体集合的交直流混合配电网鲁棒调度方法。首先,构建分布式光伏出力的传统多面体集合,利用历史数据驱动形成了相关性包络图,通过弯曲多面体集合...针对现有配电网鲁棒调度方法缺乏对不确定参数相关性问题的考虑,提出了一种基于数据驱动多面体集合的交直流混合配电网鲁棒调度方法。首先,构建分布式光伏出力的传统多面体集合,利用历史数据驱动形成了相关性包络图,通过弯曲多面体集合边界,建立了相关性多面体集合模型。然后,在此基础上,针对相关性多面体集合存在鲁棒性差和保守性大的问题,建立了数据驱动的多面体集合模型。进一步,建立了基于数据驱动多面体集合的交直流混合配电网鲁棒调度模型,并采用列与约束生成(column and constraint generation,CCG)算法对鲁棒调度模型进行求解。最后,改进的IEEE33节点系统仿真结果表明,基于数据驱动多面体集合的交直流混合配电网鲁棒调度方法可以减少优化结果的保守性,提高其鲁棒性,证明了所提出方法的有效性。展开更多
The small-island effect （SIE） has become more and more part of the theoretical framework of island biogeography and biodiversity research. However, previous methods for the detection of SlEs are often flawed in one ...The small-island effect （SIE） has become more and more part of the theoretical framework of island biogeography and biodiversity research. However, previous methods for the detection of SlEs are often flawed in one way or another, including not accounting for model complexity, not comparing all relevant models, and not including islands with no species. Therefore, the existence and the prevalence of the SIE may be dubious. In this study, after controlling for all these methodological shortcomings, we tested for the existence of the SlE in amphibian assemblages on subtropical landbridge islands created by the inundation of the Thousand Island Lake, China. We used the line transect method to determine the distribution of amphibian assemblages on 23 study islands during 3 breeding seasons from 2009 to 2011. To evaluate whether an SIE exists in amphibian assemblages, we compared the fit of a simple linearized power model with two most widely used breakpoint regression models. The information-theoretic multimodel inference approach based on Akaike＇s information criterion identified the left-horizontal SIE model as the best single model. Thus, we found strong evidence for the existence of an SIE in our system. The upper limit of the SlE for amphibian assemblages was 39.95 ha. Below this threshold area, amphibian richness varied independently of island size. The SlE in amphibian assemblages may be due to episodic disturbances, stochastic events, and nutrient subsidies from the lake. Our results indicate that all the islands 〉39.95 ha should be protected for the effective conservation of amphibian assemblages in our system.展开更多
文摘针对现有配电网鲁棒调度方法缺乏对不确定参数相关性问题的考虑,提出了一种基于数据驱动多面体集合的交直流混合配电网鲁棒调度方法。首先,构建分布式光伏出力的传统多面体集合,利用历史数据驱动形成了相关性包络图,通过弯曲多面体集合边界,建立了相关性多面体集合模型。然后,在此基础上,针对相关性多面体集合存在鲁棒性差和保守性大的问题,建立了数据驱动的多面体集合模型。进一步,建立了基于数据驱动多面体集合的交直流混合配电网鲁棒调度模型,并采用列与约束生成(column and constraint generation,CCG)算法对鲁棒调度模型进行求解。最后,改进的IEEE33节点系统仿真结果表明,基于数据驱动多面体集合的交直流混合配电网鲁棒调度方法可以减少优化结果的保守性,提高其鲁棒性,证明了所提出方法的有效性。
基金The study was supported by the National Natural Science Foundation of China （31471981, 31100394, and 31210103908）, the Project-sponsored by SRF for ROCS, SEM （J20130585） and the Fundamental Research Funds for the Central Universities （2016QNA6001 ）.
文摘The small-island effect （SIE） has become more and more part of the theoretical framework of island biogeography and biodiversity research. However, previous methods for the detection of SlEs are often flawed in one way or another, including not accounting for model complexity, not comparing all relevant models, and not including islands with no species. Therefore, the existence and the prevalence of the SIE may be dubious. In this study, after controlling for all these methodological shortcomings, we tested for the existence of the SlE in amphibian assemblages on subtropical landbridge islands created by the inundation of the Thousand Island Lake, China. We used the line transect method to determine the distribution of amphibian assemblages on 23 study islands during 3 breeding seasons from 2009 to 2011. To evaluate whether an SIE exists in amphibian assemblages, we compared the fit of a simple linearized power model with two most widely used breakpoint regression models. The information-theoretic multimodel inference approach based on Akaike＇s information criterion identified the left-horizontal SIE model as the best single model. Thus, we found strong evidence for the existence of an SIE in our system. The upper limit of the SlE for amphibian assemblages was 39.95 ha. Below this threshold area, amphibian richness varied independently of island size. The SlE in amphibian assemblages may be due to episodic disturbances, stochastic events, and nutrient subsidies from the lake. Our results indicate that all the islands 〉39.95 ha should be protected for the effective conservation of amphibian assemblages in our system.
