对雷达装备故障文本进行智能化分类,有助于提高雷达装备保障效率。针对雷达故障文本专业性强,样本量小且不平衡的问题,通过非核心词EDA进行类内数据增强,以实现在增加文本量的同时保持关键信息不变。针对非核心词EDA方法产生的新样本多...对雷达装备故障文本进行智能化分类,有助于提高雷达装备保障效率。针对雷达故障文本专业性强,样本量小且不平衡的问题,通过非核心词EDA进行类内数据增强,以实现在增加文本量的同时保持关键信息不变。针对非核心词EDA方法产生的新样本多样性不够的问题,增加SSMix(saliency-based span mixup for text classification),进行类间数据增强,通过对输入文本非线性的交叉融合来提升文本的多样性。实验证明,与现有的经典基线分类方法和典型数据增强分类方法相比,该方法在准确率上有较大幅度的提升。展开更多
The paper is devoted to mathematical modelling of static and dynamic stability of a simply supported three-layered beam with a metal foam core. Mechanical properties of the core vary along the vertical direction. The ...The paper is devoted to mathematical modelling of static and dynamic stability of a simply supported three-layered beam with a metal foam core. Mechanical properties of the core vary along the vertical direction. The field of displacements is for- mulated using the classical broken line hypothesis and the proposed nonlinear hypothesis that generalizes the classical one. Using both hypotheses, the strains are determined as well as the stresses of each layer. The kinetic energy, the elastic strain energy, and the work of load are also determined. The system of equations of motion is derived using Hamilton＇s principle. Finally, the system of three equations is reduced to one equation of motion, in particular, the Mathieu equation. The Bubnov-Galerkin method is used to solve the system of equations of motion, and the Runge-Kutta method is used to solve the second-order differential equation. Numerical calculations are done for the chosen family of beams. The critical loads, unstable regions, angular frequencies of the beam, and the static and dynamic equilibrium paths are calculated analytically and verified numerically. The results of this study are presented in the forms of figures and tables.展开更多
文摘对雷达装备故障文本进行智能化分类,有助于提高雷达装备保障效率。针对雷达故障文本专业性强,样本量小且不平衡的问题,通过非核心词EDA进行类内数据增强,以实现在增加文本量的同时保持关键信息不变。针对非核心词EDA方法产生的新样本多样性不够的问题,增加SSMix(saliency-based span mixup for text classification),进行类间数据增强,通过对输入文本非线性的交叉融合来提升文本的多样性。实验证明,与现有的经典基线分类方法和典型数据增强分类方法相比,该方法在准确率上有较大幅度的提升。
基金Project supported by the Ministry of Science and Higher Education of Poland(Nos.04/43/DSPB/0085and 02/21/DSPB/3464)
文摘The paper is devoted to mathematical modelling of static and dynamic stability of a simply supported three-layered beam with a metal foam core. Mechanical properties of the core vary along the vertical direction. The field of displacements is for- mulated using the classical broken line hypothesis and the proposed nonlinear hypothesis that generalizes the classical one. Using both hypotheses, the strains are determined as well as the stresses of each layer. The kinetic energy, the elastic strain energy, and the work of load are also determined. The system of equations of motion is derived using Hamilton＇s principle. Finally, the system of three equations is reduced to one equation of motion, in particular, the Mathieu equation. The Bubnov-Galerkin method is used to solve the system of equations of motion, and the Runge-Kutta method is used to solve the second-order differential equation. Numerical calculations are done for the chosen family of beams. The critical loads, unstable regions, angular frequencies of the beam, and the static and dynamic equilibrium paths are calculated analytically and verified numerically. The results of this study are presented in the forms of figures and tables.
