Results 11 to 20 of about 1,437,872 (201)
Dizhen xuebao, 2022 研究不同时频特性的地震波作用下，抗震结构和隔震结构耦合设备的动力响应，对五层钢框架振动台模型试验数据进行小波分析。结果表明：主结构动力响应与地震波时频特性直接相关；由于主结构和隔震支座的滤波作用，设备的动力响应受地震波时频特性影响显著，但不具有直接相关性；隔震结构可以使设备的频率远离主结构的频率，从而降低设备的放大系数；设备耦合之后主体结构加速度的变化趋势取决于不同时频特性的地震波能量分布。
Miao Han +3 more
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, 2021 该文以ys 930超空化水翼和NACA 65410水翼作为研究对象,采用RNG k-ε湍流模型、Zwart-Gerber-Belamri空化模型以及动网格技术,对比两种翼型在俯仰、升沉以及俯仰升沉复合运动情况下的水动力性能。结果表明:运动幅值的增加会使得升力系数和阻力系数曲线峰值明显提高;水翼在俯仰和复合运动情况下的升力系数和阻力系数会产生明显的尖峰,而尖峰主要是由下翼面气泡溃灭造成的。为进一步研究两种翼型的水动力性能,将升力系数和阻力系数的平均值和方差进行对比分析。结果表明 ...
杜特专, 黄晨光, 王永九
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工程施工技术, 2023 本研究旨在探究金属冷轧管机中的行星齿轮传动机构的动力学特性，以便更好地理解该传动系统在实际工作中的性能和行为。行星齿轮传动机构的动力学特性研究对于提高管机的稳定性、降低能源消耗和延长设备寿命至关重要。此外，文中还有望为行星齿轮传动的工程设计和应用提供有力的理论支持。
刘彦 巩
semanticscholar +1 more source
Gaoya dianqi, 2023 电力变压器受谐波驱动将产生频率含量丰富的振动和噪声，振动加速度和总体声功率增大将导致变压器机械和绝缘故障概率提高，影响电力系统运行的稳定性，难以满足国家标准要求，因此研究电力变压器的振动特性具有重要意义。文中首先分析电力变压器的振动来源和传递过程，并试验研究变压器整体的模态特性和振动特性，获得其各阶振型；在模态分析的基础上进一步搭建变压器振动信号测量平台，分别对变压器三相进行谐波激励下的负载试验与空载试验，分析谐波激励下变压器振动的传递过程，研究不同频率谐波下变压器的振动特性和相应变化规律。
董家睿, 李基民, 魏铭
doaj
Gaoya dianqi, 2022 操动机构是高压断路器的核心元件，其性能优劣显著影响着高压断路器分合特性。然而断路器故障时有发生，其中又以机械故障类型最为常见。因此需要提前发现潜伏性机械故障，进一步提高断路器的可靠性。针对这一问题，文中以ZN98型真空断路器弹簧操动机构为研究对象，采用Adams动力学仿真软件，建立了ZN98断路器弹簧操动机构的机械动力学仿真模型。仿真分析了操动机构各零部件运动情况，对断路器合闸与分闸过程分别进行了分析。将仿真得到的机械动力学特性作为操动机构正常工况的参照 ...
林婧 +7 more
doaj
Beyond Universalism: A Contextual Approach to Comparative Public Administration
Public Administration and Development, EarlyView.ABSTRACT In this essay, I advocate for a contextual approach to comparative public administration, arguing that effective governance reform requires moving away from universal models to embrace local political, socioeconomic, and institutional realities.
XiaoHu Wang
wiley +1 more source
Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Decomposition is the transformation of dead organic matter into its inorganic constituents. In most biomes, decomposition rates can be accurately predicted with simple mathematical models, but these models have long under‐predicted decomposition in globally extensive ...
Heather L. Throop +8 more
wiley +1 more source
Looking at Us Through Their Eyes. The Analytical Process from Ethnographic Perspectives1
Journal of Analytical Psychology, EarlyView.Abstract This article looks at the analytical situation through the Others’ eyes—through examples from contemporary ethnographies of foreign cultures. It discusses the following issues: a) The analogy between the ontological worlds of the dead, ghosts, animals and dreams in “primitive populations” and the analytical psychological descriptions of the ...
Stefano Carta
wiley +1 more source
Inferring alternative ecosystem states with field survey data
Methods in Ecology and Evolution, EarlyView.Abstract Many ecosystems potentially exhibit alternative stable states, where distinct states can coexist under identical environmental conditions. While simulation models have generated key hypotheses in alternative stable states theory, they often rely on scale‐free parameters disconnected from real ecosystems.
Ning Chen +10 more
wiley +1 more source
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
wiley +1 more source