Results 61 to 70 of about 15,531 (185)
Conservation Biology, EarlyView.Abstract Prioritization in conservation is crucial for the development of efficient and effective decision‐making policies. For many decades, the importance of some species and their habitats has been assessed and applied in conservation legislation, but bats and their diurnal roosts have ofbeen overlooked.
David López‐Bosch +6 more
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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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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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Centrifuge model test on dynamic response of sandy foundation with clay interlayer [PDF]
Natural riverbed overburden is often composed of stratified deposits of various soil types, resulting in a complex structure commonly accompanied by clay interlayers. This study conducts a series of centrifuge shaking table model tests to investigate the
CHEN Jinyi1, 2 , FU Zhongzhi1, 3 , CHEN Shengshui1, 3, CHEN Cong1, CHEN Chenghao1, 3
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Conservation Biology, EarlyView.Abstract Consumer demand for ivory perpetuates the unsustainable and illegal killing of African elephants and other wildlife species. Interventions that aim to change consumer behavior are increasingly recognized as a crucial element of demand management. However, poor design and implementation have limited their effectiveness.
Molly R. C. Brown +2 more
wiley +1 more source
Conservation Biology, EarlyView.Abstract In the western United States, conservation practitioners are increasingly working with private landowners to restore habitat for North American beavers (Castor canadensis) and to use nonlethal mitigation techniques when beavers damage crops and infrastructure.
Brian D. Erickson, Megan S. Jones
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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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Gaoya dianqi, 2022 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
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Conservation Biology, EarlyView.Abstract Despite the crucial role of human impacts on biodiversity loss, many assessments of this loss focus on single metrics, such as species richness, and overlook the multidimensional effects of human activities. Because of its importance to ecosystem functioning, we investigated the functional diversity of medium‐ and large‐sized mammal ...
Xueyou Li +8 more
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Conservation Biology, EarlyView.Abstract The design of experiments to investigate the combined effects of multiple stressors requires exposing target organisms to multiple combinations of stressor doses. Concurrent manipulation of stressors is often infeasible with wildlife, but long‐lasting health effects allow individual health to be used as an integrator of prior stressor exposure.
Enrico Pirotta +24 more
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