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Gaoya dianqi, 2021 为提高模型修正的精度和效率,发展了一种基于神经网络响应面的动力学模型修正方法,将该方法用于有载分接开关底座有限元简化模型的修正。首先,根据底座简化模型的误差来源确定待修正参数及其设计空间,采用均匀设计生成神经网络响应面模型的训练样本;然后,通过对样本数据的训练构造修正参数与动力学响应关系的神经网络响应面模型;最后,基于神经网络响应面模型,采用线性组合的多目标优化方法对底座简化模型进行修正,并将修正结果与超模型仿真数据进行对比。研究表明 ...
刘志远 +4 more
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Jianzhu Gangjiegou Jinzhan, 2022 对湛江新机场航站楼屋盖结构的屋面风荷载特性和时域法风振响应特性进行研究，分别采用分区风振系数法、分区多目标法和分区约束多目标法计算屋盖结构的等效静风荷载。结果表明：屋盖表面平均风压主要表现为负压，在垂直于风向角的屋盖迎风前缘负压最大，距离迎风前缘越远风压逐渐减小，脉动风压变化规律与平均风压基本相同。屋盖结构最大风振响应处主要位于屋面悬挑区域，结构设计时需重点关注该区域的响应。分区风振系数法等效风压分布合理，但等效响应整体误差大。以少量分区脉动风压为荷载基本向量的分区多目标法等效响应整体精度高 ...
区彤, 张佳武, 陈进于, 冯若强
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Jianzhu Gangjiegou Jinzhan, 2023 采用精细塑性铰法考虑残余应力和逐步塑性，并引入弓形效应来提高计算精度，同时基于截面组合法建立的工字形或H形截面的屈服面方程进行严格推导，提出一种单元恢复力迭代算法，减少了半理论半经验公式的使用。此外，所采用的梁柱单元还可以考虑梁构件剪切变形和几何初始缺陷的影响。相比之前的方法，该方法能在进行塑性铰分析的同时，在单元的轴力表达式中考虑二阶效应，更全面地考虑非线性因素影响。最后，通过两个经典算例的对比，证明了该方法具有高效率和高精度的特点。
朱贺, 汤轶群, 杜二峰
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Gaoya dianqi, 2023 中间接头是10 kV电缆故障的主要部位，加装防爆盒能有效避免10 kV电缆短路事故的蔓延。针对现有10 kV电缆中间接头防爆盒结构设计盲目性的问题，提出了一种基于响应曲面法的10 k V电缆中间接头防爆盒结构优化方法。首先，以钢筒内爆炸动力响应为对象，采用显示动力学软件Ls＿dyna进行了仿真计算，通过对比试验结果验证了Ls＿dyna软件对爆炸冲击模型计算的准确性；其次，以含泄压孔防爆盒爆心环面形变量为因变量，基于响应面试验设计方法开展了参数敏感性分析，结果表明：端头直径与壳体厚度是两个显著影响参数 ...
钱健 +6 more
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Gongye shui chuli, 2013 基于在pH=5.5的六次甲基四胺缓冲液介质中,氟离子对铬天青S与铝离子络合的阻抑作用,建立了测定微量氟的褪色光度法。利用响应面法优化测定条件,以反应时间、Al3+用量及铬天青S用量为影响因子,组合设计建立数学模型,以吸光度值作为响应值,进行响应面法分析。得到最佳测定条件:反应时间为66.17 s、Al3+用量为6.47 mL、铬天青S用量为5.19 mL,在此条件下,吸光度的实测值为0.687 7,相对误差为0.044%,RSD(n=3)=1.24%。
任雪峰 +4 more
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Comprehensive framework for assessing and optimizing existing research networks
Conservation Biology, EarlyView.Abstract Conservation, monitoring, and research networks, or collections of ecological research sites unified under a common mission of data collection or a research mission, are essential infrastructure for understanding large landscapes. However, most networks developed opportunistically over decades rather than through systematic design, creating ...
Alyson East +2 more
wiley +1 more source
Institutional lessons from the Nordic management model
Conservation Biology, EarlyView.Abstract To improve wildlife management outcomes, in terms of reaching management goals and increasing legitimacy, Nordic countries have developed institutional systems involving stakeholders that aim for a more inclusive and participatory model.
Jens Nilsson +2 more
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Behavioral interventions to reduce demand for threatened freshwater turtles as pets
Conservation Biology, EarlyView.Abstract Growing demand for freshwater turtles as pets has fueled illegal trade and accelerated wild population declines, underscoring the need for theory‐based demand‐reduction interventions. We conducted a three‐part randomized controlled trial with active turtle keepers (n = 1800) in China to test conservation‐ and legality‐framed messages by ...
Wuji Zheng +9 more
wiley +1 more source
Conservation Biology, EarlyView.Abstract Reversing ongoing biodiversity loss requires effectively managing anthropogenic threats. Although conservation actions can mitigate these threats, prioritizing and targeting such actions remain challenging because species respond differently depending on the nature of the threats and their biological traits.
Camila Guerrero‐Pineda +3 more
wiley +1 more source