Results 31 to 40 of about 6,416 (169)
Dianci bileiqi, 2016 结合我国电力设施抗震设计规范（GB 50260—2013）,试验数据及有限元模型,对高压电气设备法兰胶装节点弯曲刚度进行研究。采用有限元方法对500kV氧化锌避雷器建立三种不同模型,计算对比三种模型,研究法兰节点弯曲刚度。提出法兰节点刚度EI的修正系数,提供一种新的建立法兰胶装节点有限元模型的方法。
陈巍, 范荣全, 曹枚根, 卓越
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A New Finite Element Formulation for Superconvergent Eigenvalue Computation of Wave Equations [PDF]
, 2016 有限元方法是目前结构分析领域应用最为广泛的一种数值方法。自振频率计算作为结构分析中的一个重要内容，可归结为典型的特征值问题，例如：一维波动方程可描述杆结构振动，其特征值为杆结构自振频率；二维波动方程可描述膜结构振动，相应的特征值为膜结构自振频率；三维波动方程可描述声压在空间中的传播，其特征值为声压的振动频率。采用有限元法求解波动方程特征值问题时，质量矩阵的构造方法会直接影响振动频率的计算精度。因而，如何构造可使自振频率有更高收敛阶次及精度的高阶质量矩阵具有重要的研究价值。然而 ...
李希伟
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Study on mechanism and prediction of bank collapse of complex terrace bank slope in southwest China: A case study of front bank collapse in Cizhong [PDF]
Taking the bank collapse in front of the Cizhong resettlement site of the Wunonglong Hydropower Station on the Lancang River as an example, this study analyzed the bank collapse mode and,causative mechanisms, predicted the width and elevation of the bank
Guanghong JU +5 more
core +1 more source
Ultrasound in Obstetrics &Gynecology, Volume 64, Issue 6, Page 808-817, December 2024.ABSTRACT Objectives The primary aim was to validate the International Ovarian Tumor Analysis (IOTA) benign simple descriptors (BDs) followed by the Assessment of Different NEoplasias in the adneXa (ADNEX) model, if BDs cannot be applied, in a two‐step strategy to classify adnexal masses identified during pregnancy. The secondary aim was to describe the
J. Barcroft +8 more
wiley +1 more source
Petrov-Galerkin Finite Element Methods for Singularly Perturbed Convection-Diffusion Problems with Non-Smooth Data [PDF]
, 2005 摘要奇异摄动问题广泛存在于物理、力学和工程技术等科学领域，其中奇异摄动对流－扩散问题一直是个热门的研究课题，获得了很多关注[30],[31]。本文所讨论的是奇异摄动对流－扩散问题中特殊的一类，即带有不光滑数据的奇异摄动对流－扩散方程。文中分别对对流－扩散常微分方程和时间相关的对流－扩散偏微分方程两种情况进行了讨论。这类奇异摄动对流－扩散问题的特殊性在于方程中对流项的系数是不连续的，在不连续点的左边是负的，右边是正的。因此方程的精确解会在点的附近产生一个内部层，当时，方程的解在这个区域内有急剧的变化 ...
郑婷婷
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Conservation Biology, Volume 38, Issue 6, December 2024.Abstract Biodiversity research is essential for addressing the global biodiversity crisis, necessitating diverse participation and perspectives of researchers from a wide range of backgrounds. However, conservation faces a significant inclusivity problem because local expertise from biodiversity‐rich but economically disadvantaged regions is often ...
Jose Valdez +8 more
wiley +1 more source
齿轮可靠度计算的概率有限元法——第Ⅰ部分:基于齿根弯曲疲劳强度的计算
Jixie chuandong, 1992 本文结合概率有限元法与齿轮的疲劳强度理论,提出了一种预测齿轮疲劳强度可靠性的新方法。该方法的提出既解决了将概率有限元法应用于复杂结构的疲劳强度可靠性分析问题,又使齿轮的疲劳强度可靠性预测在现有水平上得以提高。本文以齿轮的齿根弯曲疲劳强度可靠性分析为例,给出了概率有限元法计算可靠度的方程与解法。算例的计算结果与实际应用情况十分相近。
吴立言, 刘更, 王步瀛
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Studies on optical properties of tip-enhanced Raman/fluorescence system [PDF]
, 2015 针尖增强拉曼光谱（Tip-enhancedRamanspectroscopy，TERS）和针尖增强荧光（Tip-enhancedfluorescence，TEF）具有极高的检测灵敏度和空间分辨率，已经成为表面科学研究中强大的表征手段。尽管TERS及TEF在近年取得了重大的进步，但依然存在许多重大的科学问题尚待解决。如TERS实验中实现的亚纳米空间分辨理论机制已不能用常规的局域电场增强理论来加以解释;进展迅速的STM-TERS技术受到样品和基底导电的严重限制而急需发展普适性更广泛的针尖增强拉曼体系 ...
孟令雁
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World Medical &Health Policy, Volume 16, Issue 3, Page 316-342, September 2024.Abstract Prior research in health equity, including food security, indicates that disadvantaged groups, such as women with limited resources, face many obstacles in achieving food security. One of the first of its kind to draw on intersectionality and the social determinants of health frameworks, this study identified and tested gender differences in ...
Farzaneh Barak +2 more
wiley +1 more source
, 1992 从Reissner壳体理论出发,将“局部-整体分析法”应用于圆柱壳孔边裂纹问题,比较精确地计算了圆柱壳孔边轴向裂纹和环向裂纹的应力强度因子,获得了应力强度因子随壳体几何尺寸、开孔大小及剪切刚度变化的规律。以作者在文[7,8]中的有限元分析结果为基础,推广Petroski-Achenbach方法,建立圆柱壳孔边裂纹问题的权函数,分析计算了圆柱壳孔边裂纹问题,获得了较好的结果 ...
吴犀甲, 柳春图, 胡互让
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