Results 61 to 70 of about 17,465 (227)
Study on hydrodynamic response characteristics of double moored floating box considering influence of connection stiffness and length [PDF]
Objective Articulated multiple floating structures are not only subject to wave excitation forces, but also to other nonlinear loads such as connection forces, mooring forces and diffraction forces between floats, making it challenging to predict their ...
Chong WANG +3 more
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Biodiversity‐driven spatial conservation planning to delineate temporally stable regions
Conservation Biology, EarlyView.Abstract The accelerating loss of biodiversity underscores the critical need for effective conservation strategies, particularly in the face of climate change and anthropogenic pressures. We devised a conservation planning framework that adopts a temporal stacking approach to species distribution models and landscape connectivity analyses. These models
Mattia Iannella +5 more
wiley +1 more source
Gaoya dianqi, 2020 文中通过在动力学仿真软件中建立断路器运动仿真模型,设置不同程度的合闸弹簧应力松弛故障,分析了合闸弹簧应力松弛对断路器操动机构运动特性的影响;采集了断路器操动机构合闸弹簧在正常及应力松弛故障下的振动信号,提出一套基于小波包敏感频段能量法的断路器合闸弹簧应力松弛故障的诊断方法。试验表明,该方法能够有效地区分弹簧是否发生应力松弛故障。
杨韧 +7 more
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Gaoya dianqi, 2021 为探究网侧设备对±800 kV换流变地震响应的影响,以某典型换流变—套管体系为对象,建立其单体有限元模型以及考虑网侧设备连接的耦联模型。网侧套管顶部滑动连接金具采用滑动接触单元进行了模拟,计算分析了地震作用下模型前20阶模态以及套管加速度、位移、应力响应。结果表明:①特高压换流变—套管体系前20阶频率接近地震卓越周期,震中易发生类共振;②网侧设备对换流变阀侧套管地震响应无影响,但会显著放大网侧套管顶部位移响应和根部应力响应;③地震作用下,网侧套管顶部连接金具内部的相对滑移响应显著。因此 ...
杨旭 +5 more
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Structural load inversion and state analysis of floating wind turbine tower based on joint input-state estimation [PDF]
ObjectiveThis study uses the structural load inversion method to conduct a dynamic response state analysis of a floating wind turbine tower under wave action.
Chao WANG +4 more
core +1 more source
Drivers of bat researchers’ intent to adopt field hygiene practices
Conservation Biology, EarlyView.Abstract Infectious disease is a growing threat to wildlife, with zoonotic transmission most likely at the human–wildlife interface. One underappreciated activity at this interface is fieldwork with wild animals, but associated risks can be mitigated through field hygiene (FH) practices, such as using personal protective equipment and other appropriate
Joanna L. Coleman +6 more
wiley +1 more source
Real-time identification of time-varying structures and integration with vibration control based on extended Kalman Filter with unknown inputs [PDF]
, 2017 建筑结构的参数识别与损伤诊断是结构健康监测领域中的一项重要课题。在过去的数十年内，业内许多专家与学者给出了理论各异的，基于结构振动响应的参数识别与损伤诊断方法。然而，这其中的许多方法，大都是针对于时不变系统的。但在重大荷载发生时（如高烈度地震等），结构单元发生损伤，它的物理参数（如刚度等）在荷载作用中是随时间变化的。为了实时地捕捉这一变化，结构健康监测系统应该具备在线地识别时变结构参数的能力。 因此本论文在第二章，在前人基础上得到了基于改进的自适应卡尔曼滤波的时变系统在线识别方法。与现有文献相比 ...
王龙飞
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International Journal of Applied Linguistics, EarlyView.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
Synthesizing Empirical Research on Learner Metacognition in Second Language Writing
International Journal of Applied Linguistics, EarlyView.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
Jixie chuandong, 1991 本文对一完整双联斜齿轮在动载荷和离心力作用下结构中的位移和应力场进行了计算研究。首先建立了双联斜齿轮的三维有限元模型,用[1]中的方法求得了相应结构振动最低几阶固有频率及振型。用模态坐标变换将有阻尼弹性系统二阶常微分有限元动态运动方程组转换成无耦合微分方程,根据系统计算出的真实动载荷用振型叠加法计算了双联斜齿轮的稳态响应。本文还研究了离心力对齿轮位移及应力分布的影响,并与齿轮结构中的动位移及动应力进行了对比分析。全文的计算是在微机上完成的。
刘更, 何大为, 沈允文, 高向群
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