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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 二维瞬态传热模型仅对构件横截面内两个维度的高温传热进行模拟，若需考虑轻钢组合构件纵向各横截面间的传热影响，需建立三维数值传热模型。建立了轻钢组合构件三维传热有限元精细模型，考虑了空腔热传导、热对流和热辐射作用及构件纵向传热的影响，数值模拟结果与试验结果吻合良好，并在此基础上对组合构件的纵向传热进行了研究。为节省三维传热模拟的计算时间，提出利用热传导作用等效空腔对流作用的简化处理方法，并将二维等效简化方法及所推导的等效导热系数用于三维等效简化模型的建立。将模拟结果与试验结果进行对比 ...
叶继红, 徐焱
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Gaoya dianqi, 2021 油浸式配电变压器由于表面布有大量散热片,使得油箱辐射声场计算与结构优化分析变得困难,因此文中确定了一种考虑散热片的油箱结构模态分析以及声场计算方法。通过引入惯性矩参数对散热片结构进行等效简化建模,将简化模型得到的模态分析结果作为参考依据,从完整变压器模型模态计算结果中筛选出变压器的真正模态振型与固有频率;此外通过分析线性插值与模态扩展两种方法对声场计算结果的影响,确定了更为可靠的声场计算方法。结果表明,采用惯性矩等效的简化模型在前三阶主要模态结果与完整结构模型结果十分接近,具有很好的参考性 ...
胡静竹 +4 more
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Jianzhu Gangjiegou Jinzhan, 2022 提出一种钢管混凝土柱-横肋波纹钢板剪力墙，其中横肋波纹钢板作为主要抗剪单元以其较大的面外刚度和良好的抗整体屈曲性能有效延缓了面外失稳的发生，并提供了稳定的抗侧承载力。多根钢管混凝土柱与波纹钢板组合形成的异形剪力墙可适应住宅钢结构中的墙体转角造型，且能够有效提高剪力墙的面外稳定性能。在结构应用设计时，需提出该新型体系的合适简化分析模型。根据横肋波纹钢板剪力墙的构造组成和力学特性，提出采用正交异性板单元的简化模拟方法，在MIDAS软件中建立典型异形剪力墙的简化模型并与ABAQUS模型进行对比 ...
胡婉颖, 余玉洁, 赵凤涛
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Gaoya dianqi, 2020 中压开关柜内部电弧故障时有发生,其短时间释放出的巨大能量引起隔室内部压力迅速上升,对设备、建筑物以及工作人员的安全造成了严重威胁。基于零部件规则化和隔室等容积替代的简化原则,提出了开关柜复杂模型简化方法;利用CFD法计算了不同简化模型的压力分布规律,给出了模型最优简化方法;对SCM法与CFD法获得的计算结果进行了对比,分析了两者的差异。结果表明:采用规则化—等容积替代混合方式简化模型获得的结果与原始模型吻合较好,计算时间缩短了约54.39%;当泄压板打开后,隔室内部的压强分布差异较大 ...
吴田 +5 more
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Assessing differences among elasmobranch nurseries to aid conservation based on a genomics framework
Conservation Biology, EarlyView.Abstract Elasmobranch nurseries often differ in environmental conditions, demographics, and use patterns. These differences affect the distribution of genetic variation among nurseries. However, conservation and management strategies often fail to account for such differences because they are difficult to characterize.
Dominic G. Swift +8 more
wiley +1 more source
Emerging applications of large language models in ecology and conservation science
Conservation Biology, EarlyView.Abstract Large language models (LLMs) mark a major development in artificial intelligence, with potentially transformative implications for ecology and conservation science. Built on advanced deep‐learning architectures, these models can support a wide range of tasks. We reviewed emerging applications of LLMs, drawing on the wider scientific literature
Christos Mammides +5 more
wiley +1 more source
Learning Styles, Engagement and Anxiety in AI‐Mediated Writing: A Multimodal Feedback Study
International Journal of Applied Linguistics, EarlyView.ABSTRACT Artificial intelligence (AI) tools now permeate English academic writing. However, evidence on how feedback modalities align with student differences and with psychological mechanisms remains limited. Prior work often reduced learning styles to simple matches with delivery modes and treated learning engagement and writing anxiety as peripheral.
Yi Ren +3 more
wiley +1 more source
Running With Scissors? Integrating GPT Models Into Public Policy Research
Policy Studies Journal, EarlyView.ABSTRACT The integration of large language models (LLMs) into public policy research presents both exciting opportunities and methodological challenges. This research note explores how OpenAI's GPT can be used to semi‐automate the annotation of legislative testimony within the Advocacy Coalition Framework, focusing on emotion‐belief dyads.
Giulia Mariani, Allegra H. Fullerton
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Gaoya dianqi, 2022 模块化多电平变换器（MMC）的电热耦合模型对于系统结温监测、可靠性分析、寿命预测等具有重要意义。文中提出了一种合理简化的模块化多电平变换器电热耦合模型，首先基于后退欧拉法，建立MMC子模块的等效电路；然后根据戴维南电路等效方法，建立了三相MMC等效电路；其次，根据器件损耗特性和热阻抗特性建立MMC的电热耦合模型；最后，通过仿真和实验结果，验证了所提MMC电热耦合模型的正确性，该模型可以用来做MMC特性研究和可靠性分析。
张玉斌, 杨张斌, 温英科, 阮琳
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