Results 21 to 30 of about 14,805 (141)
传动链运动精度的大小可用均值、方差、偏倚系数、偏峰系数4个参数决定。本文主要讨论了传动比及传动链结构型式对空程的上述4个参数的影响;给出了上述影响的定量变化曲线 ...
薛澄岐, 卢世济
doaj
温室单层球面网壳的稳定性在设计中起着控制作用,尤其是非对称(半跨均匀)荷载、初始几何缺陷(节点偏差)、矢跨比和拉索预应力等因素对温室单层球面网壳稳定性的影响还有待深入研究。基于构形易损性理论,提出了判断参数对极限承载力影响的指标,即节点构形度的差异系数。利用ANSYS软件对矢跨比分别为1/3、1/5和1/7的K6、K8型温室单层球面网壳进行了整体刚度矩阵的提取,并通过MATLAB自编程序计算得到节点构形度的差异系数,定性分析了各参数对极限承载力的影响与节点构形度的差异系数的关系。研究表明 ...
卢珍, 李会军, 饶颢
doaj
Learning Styles, Engagement and Anxiety in AI‐Mediated Writing: A Multimodal Feedback Study
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
针对单级同步感应线圈炮系统中影响弹丸速度和系统效率的主要因素——驱动线圈和电枢的结构参数、电容器的电容和放电电压以及电枢的触发放电位置,笔者对不同结构参数的单级同步感应线圈炮物理模型进行有限元分析与仿真,得出各项结构参数对弹丸速度的影响规律,提出了一组最佳的结构参数并根据优化的结构参数进行了发射实验。仿真和实验结果均表明该结构参数可以有效地提高弹丸速度和系统效率。
邹本贵 +3 more
doaj
ABSTRACT Generative artificial intelligence (GenAI) has emerged as a powerful tool in the Informal Digital Learning of English (IDLE) environment, offering personalized, interactive, and innovative language learning experiences that may enhance learning engagement.
Jin Liu, Meilu Liu, Yuan Yao, Dechao Li
wiley +1 more source
以上海辰山植物园铝合金展览温室为背景,研究摩擦系数对结构性能的影响。与常规结构滑动支座不同,该项目滑动支座条件复杂。滑动支座数量众多,并形成一闭合回路,同时各支座不在一个水平标高上,因此滑动支座的性能对整个结构的影响较大。通过程序分析,研究不同支座摩擦系数下结构的受力和变形性能,从而为支座构造的设计提供技术参数。通过研究发现,当支座摩擦系数小于0.01时,杆件内力与理想无摩擦情况误差小于5%,可以不用考虑摩擦力对结构性能的影响,设计时释放支座相应的自由度即可。
张良兰
doaj
Legislating Uncertainty: Election Policies and the Amplification of Misinformation
ABSTRACT Can state election policies affect the spread of misinformation? This paper studies the role played by ballot processing policies, which determine when ballots can be examined and organized, in the online spread of political misinformation. We present evidence from the 2020 U.S.
Morgan Wack +5 more
wiley +1 more source
ABSTRACT In the face of increasingly complex environmental challenges, subnational governments play a critical role in implementing climate policies. This study investigates how intergovernmental interactions—specifically formal authority interactions and informal competitive interactions—shape the adoption of climate policies by Chinese provincial ...
Shiming Zheng, Alex Jingwei He, Yujie He
wiley +1 more source
为了研究基于耗能梁削弱的结构配置方案对配置耗能梁的高强钢框架结构的抗震性能和损伤控制效应的影响,建立并验证了配置耗能梁的高强钢框架结构的"塑性铰-梁单元"数值模型,通过配置不同削弱等级的耗能梁设计得到了具有不同屈服时序系数的3层及9层算例结构,并进行非线性静力分析和地震时程分析。研究结果表明,耗能梁削弱能够有效增大屈服时序系数,其对结构的峰值变形影响相对有限,而对震后残余变形影响显著。耗能梁的适度削弱将降低主体结构的塑性发展程度,但过度削弱将加剧耗能梁的损伤发展以至于主体结构的塑性发展程度转而增长。最后,
邓露, 谢吴华, 柯珂
doaj
The Microstructure Evolution and Mechanical Properties of (FeCoCrNi)100‐x(AlCu)x High‐Entropy Alloys
ABSTRACT This study systematically investigates the effects of AlCu addition on the microstructural evolution and mechanical properties of (FeCoCrNi)100‐x(AlCu)x (x = 0, 5, 10, 15, 20; at%) high‐entropy alloys (HEAs). The results reveal that the microstructure evolves from coarse equiaxed to refined equiaxed, dendritic, and ultimately dual‐phase ...
Shunfu Xie +7 more
wiley +1 more source

