Results 21 to 30 of about 9,360 (160)
, 2017 针对LED驱动电源的品质影响LED产品性能的问题,设计了一套LED驱动电源系统方案.对驱动电源的高频直流转换器电路、PWM控制电路、反馈电路进行设计与实现;实验结果表明,所设计LED驱动电源系统各模块工作稳定可靠 ...
黄志兵
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Research on Bearing Capacity of Angle Steel Transmission Tower Subject to Parallel Reinforcement by Fitting Channel Steel [PDF]
, 2023 [Introduction] The existing angle steel transmission tower has been running for many years, and the structural damage leads to the reduction of service performance.
Donghong ZHANG +4 more
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Dizhen xuebao繁琐复杂的静动力边界转换处理是进行静动力耦合模拟的关键步骤，为了研究黏弹性边界条件下传统静动力边界转换的合理性及其验证方法的适用性，本文首先根据弹性叠加原理提出了一种验证静动力耦合模拟分析中静动力边界转换合理性的方法（参考解法）；然后基于有限元软件ABAQUS，并结合自行研发的适用于成层介质的黏弹性边界施加和等效节点力计算程序VBEA2.0，对多土层自由场静动力耦合模型和土-地下结构静动力耦合模型进行了地震反应分析，对参考解法的适用性进行了探究；最后使用本文提出的参考解法 ...
Shengjie Ma +5 more
doaj +1 more source
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
core
Motion and force analysis of mold open-closing mechanism with electric eight-bar for food packaging thermoforming machine [PDF]
Objective: To solve the technical problems in the design and analysis of the core parts of the mold open-closing mechanism related rod. Methods: The motion and force analysis of mold open-closing mechanism with an electric eight-bar was described in ...
CHEN Xiaoqin, XIE Zhigang, XU Zhiyang
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Failure characteristics and reasonable width of water-resisting pillar under the coupling effect of mining and seepage [PDF]
, 2023 The coupling failure induced by the influence of mining practice and the water immersion softening of the water-resisting coal pillars in old goaf is one of the common causes of water inrush accidents in the same seam working face.
Chengen QI +5 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT A major challenge in fabricating eutectic NiTiNb alloys is the incomplete melting of Nb due to its much higher melting point than the NiTi matrix. In this work, a novel electron‐beam freeform additive manufacturing strategy is developed to eliminate unmelted Nb particles and achieve a fully eutectic structure through independent dual‐wire ...
Qing‐Da Zhang +9 more
wiley +1 more source
Efficient Simulation Methods for Reinforced Concrete Columns with Encased Steel in High-rise Building Structures [PDF]
, 2016 型钢混凝土柱在建筑结构中往往是主要的承重构件之一，使用合适的数值模型分析其力学性能对高层结构抗震分析有重要的意义。本文综述了目前文献中已有的低含钢率恢复力模型相关研究，分析了其理论、计算流程和算法，并在通用有限元软件OpenSees中编程实现。本文详细推导了模型中基本参数的确定方法，并用于模拟实际高层建筑结构中的型钢混凝土柱。首先，本文用恢复力模型模拟了单根型钢混凝土柱的试验，通过对比验证了模型的精度，研究了其计算效率。其次，本文将恢复力模型用于理想32层高层结构中的单排型钢混凝土构件静、动力分析中 ...
曾志弘
core
The Two Faces of Introgression in Conservation Biology 基因渗入在保育生物学中的双重面貌
Integrative Conservation, Volume 4, Issue 3, Page 339-344, September 2025.Conservation biologist need to take into account the various aspects of introgression in their attempts to protect the species integrity and evolutionary potential of threatened species. To do so, they have to overcome the bias created by the Mayrian species concept that considers species as having distinct gene pools.
Harald Schneider, Charles H. Cannon
wiley +1 more source
Dizhen xuebao本文基于荷载路径法，利用节点位移和承载力对主厂房山墙结构中的关键柱进行判别，然后采用静力与动力非线性分析方法，讨论了山墙结构的塑性铰以及失效柱竖向位移和转角变化，并对剩余结构的抗连续倒塌性能进行了分析。结果表明：关键柱的边柱失效对于剩余结构抗连续倒塌能力的影响更大，与构件重要性分析的结果相一致；静力非线性分析因考虑了荷载放大效应，其预测的抗倒塌能力普遍高于动力分析结果。相较于增加配筋量或增大截面尺寸的传统方法，增加斜杆或优化支撑布局对提升核电站常规岛主厂房框排架结构的抗连续倒塌和变形能力更有效。
Pengfei Qi +4 more
doaj +1 more source