Results 41 to 50 of about 17,465 (227)
Effects of parachute science on local research capacity 降落伞科学对当地研究能力的影响
Conservation Biology, EarlyView.Abstract Strengthening research capacity is essential to address the global biodiversity crisis. Yet, parachute science often undermines this goal, and its prevalence, costs, and benefits are unclear. We analyzed 13,502 publications on primate research that we extracted from Scopus (1960–2022) to evaluate the effects of parachute science on local ...
Li Yang +11 more
wiley +1 more source
Dianci bileiqi, 2018 为研究复合材料支柱绝缘子的地震响应,本文对换流站用±1 100 kV复合支柱绝缘子进行了振动台试验,研究了该支柱绝缘子的动力特性,加速度响应,位移响应以及应力响应。试验结果表明:该支柱绝缘子的前三阶频率分别为0. 63 Hz、3. 90 Hz以及10. 75 Hz,阻尼比约为3. 7%。支柱绝缘子的加速度响应峰值、相对位移响应峰值以及根部应力响应峰值均随地震动峰值加速度的增大（0. 1～0.
刘海龙 +3 more
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Dynamical Mechanisms of Upper Oceanic Response to Tropical Cyclones [PDF]
, 2017 海洋对热带气旋的响应和反馈机理是海洋与大气科学的研究热点，也是准确预报热带气旋强度和相关海洋环境变化的关键所在。本文结合现场观测、数值模拟和理论分析，着重研究上层海洋对热带气旋的响应特征和机制。首先采用2014年和2016年两组南海北部的浮标/潜标实测资料，针对几个过境的热带气旋（特别是台风海鸥）开展个例分析和数值模拟；在此基础上，再从理论上进一步探讨一般情况下海洋对热带气旋的动力学响应机制。 台风海鸥于2014年9月经过南海观测阵列上空，导致局地风速迅速增加并伴随着大气压强降低、路径右侧（左侧 ...
张翰
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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
wiley +1 more source
Shiyou jixie, 2015 为了研究J型铺设升沉运动对管道应力的影响，利用ABAQUS软件对管道进行有限元建模，分析了不同水深、铺管角度和管道容重下船体下方10 m和TDP附近管道的动态响应。建模时采用PSI单元模拟管道与海底土壤之间的相互作用，将土壤反力定义为非线性。分析结果表明，在船体升沉运动影响下，轴向张力的变化是导致管道应力变化的重要因素；TDP附近的应力变化不仅要考虑轴力变化，还要考虑弯矩变化；若以增大壁厚的方式增大容重，则管道抗弯刚度增大，尽管TDP处管道静态应力呈增大趋势，但最大动态应力相差不大 ...
焦晓楠 +5 more
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Dizhen xuebao, 2019 以地下隧道对附近场地动力特性的影响为研究目标，基于弹性波动理论，利用波函数展开法和镜像法，分析了弹性半空间中圆形衬砌隧道对平面SH波入射产生的散射问题，得到了地下圆形衬砌隧道附近场地位移的级数解答。通过数值算例分析了地下圆形衬砌隧道对场地动力响应的影响，重点考察了SH波入射角度、入射频率和隧道埋深、衬砌刚度对隧道周围土体动力响应随深度变化的影响规律。结果表明，地下隧道对沿线场地的地下地震动影响显著。
Fengxi Zhou, Lingmeng Gao, Qiang Ma
doaj +1 more source
Wet-towing coupled dynamic response of three-bucket jacket foundation of offshore wind power [PDF]
ObjectiveTo improve the safety of wet-towing transportation for offshore wind power multi-bucket jacket foundations, it is necessary to explore the stability and dynamic response during the wet-towing transportation.MethodsA hydrodynamic model was ...
Disheng LIANG, Puyang ZHANG, Xiling QI
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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
, 2018 几何非线性是土木工程结构在强震作用下动力时程分析过程中必要的考虑因素。该文基于数值子结构方法,结合平面Euler-Bernoulli梁柱单元的几何大变形理论,将平面框架结构的非线性分析转化为线弹性主结构的弹性分析,并提出材料和几何非线性修正力项,作为等效为外荷载项施加于主结构以考虑结构的双非线性。最后,对一平面钢框架结构进行地震动力时程分析,分析结果表明考虑了双非线性的数值子结构方法具有良好的精确性与高效性;同时,几何非线性对结构动力响应具有重要影响。国家自然科学基金项目(51261120376 ...
古泉, 孙宝印, 张沛洲, 欧进萍
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Seismic dynamic response analysis for tunnels considering coseismic displacement [PDF]
Fault dislocation is a form of dynamic impact load that induces permanent deformation of the stratum in the vicinity of the fault. Based on the finite-fault source and crustal velocity model, coseismic displacement is computed according to the layered ...
FENG Jun1, 2 , ZHAO Boming1, 2 , WANG Zijun1, 2
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