Results 21 to 30 of about 1,726,000 (149)
Zhejiang Daxue xuebao. Lixue ban, 2023 针对三维非牛顿流体充填问题，建立了有限元-间断有限元耦合算法。对于两相Navier-Stokes方程，基于压力增量修正格式分三步求解，分别采用二次和一次拉格朗日插值多项式求解速度和压力，以确保计算过程稳定。采用守恒型水平集（level set）方法追踪运动界面，并依据间断有限元方法求解水平集和重新初始化方程。以三维圆球剪切流动及非牛顿流体三维平板型腔充填过程为例，并与已有文献的数值和实验结果进行比较，以验证数值算法的稳定性、准确性以及流体的质量守恒性。
高普阳(GAO Puyang)
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World Food Policy, Volume 12, Issue 2, November 2026.ABSTRACT Agricultural development initiatives in sub‐Saharan Africa have emphasized improved crop varieties as a pathway to food security, resilience, and rural poverty reduction. However, empirical evidence often focuses narrowly on plot‐level outcomes and overlooks whole‐farm effects and the substantial heterogeneity in farmers' management practices,
Kodjo Kondo +4 more
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Dizhen xuebao为了充分发挥谱元法和有限差分法各自在数值模拟复杂介质中地震波传播的优点，同时避免各自缺点，本文提出了模拟地震波传播的谱元-有限差分（SEM-FDM）混合方法。该混合方法在起伏地形附近采用谱元法计算地表附近的地震波传播；在远离起伏地形的区域之下，采用有限差分法计算地震波传播；之后通过构建数据交换区实现两种方法的耦合。结果表明，本文提出的谱元-有限差分混合方法能有效地模拟任意非均匀介质中的地震波传播，具有刻画复杂地形的能力，能处理自由地表边界条件，且能适应模型内的速度间断面。通过模型试算，并与谱元法进行对比，
Changzhi Xu +6 more
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Evaluating the use of taxonomy in the IUCN Red List
Conservation Biology, Volume 40, Issue 5, October 2026.Abstract Taxonomy defines the units that conservationists strive to preserve for future generations. However, the discovery of new species and the taxonomic revision of existing species affect conservation efforts. Despite the importance of taxonomy for a species’ conservation, there is currently no overview of how those leading species extinction risk
Stephen T. Garnett +8 more
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, 1981 1.引言由几块平板组成的空间结构在工程上得到广泛应用.其动力、静力问题是很难用经典材料力学和弹性力学方法解决的.有限元方法是解决这类问题的强有力手段.各国力学工作者已经发展了很多解决板壳问题的有限元素法,Zienkiewicz 等提出的位移法有限元公式是最常用的,这个元素的位移函数在边界上一阶法向导数不连续是它的最大缺点,另外一些人提出的位移法边界协调元素公式太复杂 ...
张双寅
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Gaoya dianqi, 2005 利用基于边单元的有限元法,对一台200km/h高速电力机车主变压器的油箱损耗进行了三维有限元分析和计算。由于电力机车主变压器是高漏抗,多绕组变压器,经试验（采用放大法）得到该台变压器油箱损耗为31.245kW,使用FEM二维有限元分析法计算结果为45.791kW,而采用三维有限元分析法计算结果为30.478kW。从而表明,采用三维有限元分析能够更加准确地计算主变压器油箱的涡流分布和杂散损耗,为其采取有效的屏蔽措施提供了更加可靠的科学依据。
李季, 罗隆福, 许加柱
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Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Electrochemical carbon dioxide reduction reaction (CO2RR) powered by renewable electricity offers a sustainable route for producing value‐added carbonaceous chemicals. Herein, a three‐membrane electrolyzer was employed to directly co‐generate carbon monoxide (CO), chlorine (Cl2), and potassium carbonate (K2CO3) from the electrolysis of CO2 and
Shuai Wu +10 more
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四川大学学报. 自然科学版, 2013 Darcy-Stokes方程的统一有限元方法是研究Darcy-Stokes耦合问题的基础.尽管该方法采用等阶或低阶有限元逼近在工程计算上有较大的实际应用价值,但这类有限元组合不满足inf-sup条件,因而会造成数值求解的困难.而非协调有限元更容易满足离散的inf-sup条件,因而在计算耦合问题时比协调有限元更具吸引力.本文对Darcy-Stokes方程提出了一种等阶线性非协调稳定化有限元方法,证明了该格式是稳定的,并得到了最优误差估计.
刘程熙, 孔花, 钟纯真
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Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Tin‐based composite oxides typically undergo severe volume variations and exhibit poor intrinsic conductivities despite their high theoretical capacity as promising anode candidates for sodium‐ion batteries. This results in rapid structural degradation and capacity fading upon cycling.
Yongmei Sun +5 more
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, 2007 介绍一种能够模拟岩石材料破坏过程的有限元方法,该方法引入单元分裂和界面分离技术描述破坏引起的材料几何拓扑结构变化,采用接触单元表征破坏界面,借助动态松弛方法完成求解。该有限元方法主要针对岩石材料的张拉和剪切两种破坏形式 ...
丁桦, 邱峰
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