Results 51 to 60 of about 18,258 (182)
Dynamic Analysis of a High-rise-Building Structure during an Earthquake Considering Soil-Structure-Interaction [PDF]
土-结构体系有限元模拟计算分析的复杂性与计算成本,在一定程度上限制了土与结构相互作用分析在高层建筑结构设计中的应用。上部结构数值解与土解析解耦合的土-结构相互作用计算方法,为高层建筑结构提供了有效途径。利用作者提出的耦合算法,对一个钢框架-混凝土核心筒高层结构进行地震作用下的非线性动力分析,讨论了不同强度地震和不同种类地基土对结构地震反应的影响,得出了对实际工程具有指导性意义的结论。The conventional coupling analysis based on a comprehensive ...
卢佳盛, 孙宝印, 李勇
core +1 more source
Synthesizing Empirical Research on Learner Metacognition in Second Language Writing
ABSTRACT Despite considerable research interest in learner metacognition in second language (L2) writing, there is not yet a review that synthesizes the existing empirical findings and discusses their implications. To fill the void, this systematic review synthesized 39 empirical studies on learner metacognition in L2 writing and examined their salient
Chen Li, Icy Lee, Zhicheng Mao
wiley +1 more source
Investigation on Aerodynamic Characteristics of Long-Grouped High Speed Train Subjected to Crosswind [PDF]
采用定常RANS方法,对长大编组高速列车的横风气动特性进行分析,从流场特性和气动力特性两个方面开展研究。结果表明,横风条件下,列车表面流动现象非常丰富,列车首尾流线型存在较多流动分离、再附等现象,且受横风侧偏角影响较大。在列车背风侧出现两个以上的复杂分离涡系,从列车头车下部开始,向列车下游发展并逐渐远离列车车体。分离涡系是列车承受非定常气动力的根源。列车头车是侧向力、滚转力矩最严峻的车厢,且随着横风侧偏角增大,侧向力、滚转力矩逐渐增大 ...
孙振旭, 尚克明, 杜健
core
ABSTRACT Despite extensive research on policy diffusion, the ways in which policy attention influences this process remain underexplored. This study addressed this gap by distinguishing between three types of policy attention—political speeches, policy issuance and field visits—and investigating their differential impacts when delivered by central and ...
Xiangning Chen, Yahua Wang
wiley +1 more source
Analysis on the Elastic Lateral Stiffness under Seismic Action for Palace Structure in the Building Standards of Song Dynasty [PDF]
中国古代木构架房屋具有良好的抗震性能,其中凝结了长达数千年间古代的建筑工程经验与智慧。这种“干架”结构有别于现代刚接杆系结构,其结构受力分析尚不能直接套用现代框架结构计算方法。已有的研究,通过缩尺模型试验,回归分析,拟合出类似于现代钢筋混凝土框架结构的动力学方程,尚未能揭示出符合古代设计思想及技术水平的基本原理。从古代房屋结构的设计、建造方法入手,探寻其本源的科学原理,一方面可以为古代建筑的安全性能评价找到一般性的方法,另一方面,古为今用,可以为现代工程建设带来新的启迪。 本文在深入研读《营造法式 ...
黄燕萍
core
The Inclusion Trade‐Off: Comparing the Design and Functionality of Collaborative Governance Forums
ABSTRACT Environmental challenges require collaboration across jurisdictions, often through forums or intermediary spaces for repeated interaction. A persistent forum design question concerns inclusion criteria, or which actors should be included.
Adam Wiechman +3 more
wiley +1 more source
海洋核动力小堆作为未来海洋核能应用的重要形式,其热工水力特性受到周期性流体波动和复杂运动的影响,增加了设计与安全评估的挑战。本研究旨在开发一种多尺度分析方法,通过适应性改造和多层次模拟,系统评估海洋条件下核动力小堆的热工水力行为与安全性。首先,选用STAR-CCM+作为改造系统分析、子通道和计算流体力学(Computational Fluid Dynamics,CFD)等程序的工具,对RELAP5源程序进行了修改,对海洋小堆进行简化建模,以适应海洋环境下的系统行为、组件传热、燃料棒束等关键特性;其次 ...
罗 涵禹, 宋 厚德, 刘 晓晶
doaj +1 more source
海上风电联接变压器作为海上风电场的主要设备,其抗震安全性关系到海上风电场的平稳运行。针对海洋平台—附属电气设备在地震作用下的动力传递过程及楼层反应谱研究,以及电气设备的动力响应特性和自身薄弱部位研究,开展了变压器1∶10模型比尺的振动台模型试验研究;模型试验与数值仿真分析结果的对比表明,海洋平台的动力特性会显著影响传递至设备底部的地震加速度的低频部分;结构的应力薄弱部位发生在储油柜下方支架处。基于弹性相似的振动台缩尺模型试验可以反映原型结构的地震动响应特性,为附属设备的抗震反应谱研究提供依据 ...
陈健云 +7 more
doaj
Unpacking Welfare Deservingness Theory: Evidence From the Perceived Deservingness of Gig Workers
ABSTRACT The theory of welfare deservingness provides valuable insights into the social legitimacy of welfare programs and the principles underlying policy design. In examining the question of who deserves what and why, established deservingness criteria emphasize that individuals demonstrating motivation to work (“reciprocity”) are typically perceived
Juhyun Bae
wiley +1 more source
随着电网系统的快速发展,大容量、高电压电力变压器不断增多,其振动与噪声对设备自身及周边居民的健康造成的影响日益凸显,因此变压器振动与噪声及其控制受到了国内外学者的广泛关注。文中从变压器振动噪声机理、特性、影响因素以及控制措施等方面对国内外研究进展进行综述。分析了硅钢片的磁致伸缩特性及Maxwell应力特性,得出铁心振动噪声的主要来源及数学模型;根据绕组磁场分布及受力分布,分析了绕组轴向及幅向振动特性及数学模型;总结了冷却设备等部件的振动特性。从振动产生、传递到噪声辐射等过程分析了变压器传播特性。从激励 ...
汲胜昌, 师愉航, 张凡, 陆伟锋
doaj

