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171.
In this paper, a discrete KdV equation that is related to the famous continuous KdV equation is studied. First, an integrable discrete KdV hierarchy is constructed, from which several new discrete KdV equations are obtained. Second, we correspond the first several discrete equations of this hierarchy to the continuous KdV equation through the continuous limit. Third, the generalized (m, 2N − m)-fold Darboux transformation of the discrete KdV equation is established based on its known Lax pair. Finally, the diverse exact solutions including soliton solutions, rational solutions and mixed solutions on non-zero seed background are obtained by applying the resulting Darboux transformation, and their asymptotic states and physical properties such as amplitude, velocity, phase and energy are analyzed. At the same time, some soliton solutions are numerically simulated to show their dynamic behaviors. The properties and results obtained in this paper may be helpful to understand some physical phenomena described by KdV equations. 相似文献
172.
The (2+1)-dimensional Boiti–Leon–Manna–Pempinelli (BLMP) equation is an important integrable model. In this paper, we obtain the breather molecule, the breather-soliton molecule and some localized interaction solutions to the BLMP equation. In particular, by employing a compound method consisting of the velocity resonance, partial module resonance and degeneration of the breather techniques, we derive some interesting hybrid solutions mixed by a breather-soliton molecule/breather molecule and a lump, as well as a bell-shaped soliton and lump. Due to the lack of the long wave limit, it is the first time using the compound degeneration method to construct the hybrid solutions involving a lump. The dynamical behaviors and mathematical features of the solutions are analyzed theoretically and graphically. The method introduced can be effectively used to study the wave solutions of other nonlinear partial differential equations. 相似文献
173.
Wen-Jin Yin Xiao-Long Zeng Bo Wen Qing-Xia Ge Ying Xu Gilberto Teobaldi Li-Min Liu 《Frontiers of Physics》2021,16(3):33501
Heterostructure is an effective approach in modulating the physical and chemical behavior of materials. Here, the first-principles calculations were carried out to explore the structural, electronic, and carrier mobility properties of Janus MoSSe/GaN heterostructures. This heterostructure exhibits a superior high carrier mobility of 281.28 cm2·V−1·s−1 for electron carrier and 3951.2 cm2·V−1·s−1 for hole carrier. Particularly, the magnitude of the carrier mobility can be further tuned by Janus structure and stacking modes of the heterostructure. It is revealed that the equivalent mass and elastic moduli strongly affect the carrier mobility of the heterostructure, while the deformation potential contributes to the different carrier mobility for electron and hole of the heterostructure. These results suggest that the Janus MoSSe/GaN heterostructures have many potential applications for the unique carrier mobility. 相似文献
174.
175.
提出了一种基于分数阶傅里叶变换的模式测控一体化方法。利用分数阶傅里叶变换光路对光纤模式耦合态进行空间调制和相位调制,以实现模式的有效分解。与双重傅里叶变换(F2)法以及空间和频谱成像(S2)法相比,采用的分数阶傅里叶变换法,通过改变分数阶参数,控制模式的空间分布以及模式间的叠加状态,更易于分解出高阶模式。基于分数阶傅里叶变换的模式测量方法可在更广泛空间,研究模式的空间和相位叠加以及模式分解,也可退化为F2法和S2法。 相似文献
176.
177.
应用牛顿运动定律对一个有关斜面体小车上的物体在摩擦力作用下随小车一起做简谐运动问题的错误解法进行辨析,并给出正确的解答方法. 相似文献
178.
给出了单个均匀带电圆环在轴线上各点产生的场强随距离变化的关系式和极值条件以及图像并分析其特点,利用图像叠加法对有关两个均匀带电圆环在轴线上产生电场的问题进行巧妙解答. 相似文献
179.
Journal of Visualization - The increasing availability of spatiotemporal data provides unprecedented opportunities for understanding the structure of an urban area in terms of people’s... 相似文献
180.
Correlations of conserved charges,i.e.,the baryon number,electric charge,and strangeness,are calculated at finite temperature and chemical potentials up to the fourth order.The calculations are done ina 2+1 flavor low energy effective theory,in which the quantum and thermal fluctuations are encoded through the evolution of flow equations within the functional renormalization group approach.Strangeness neutrality and a fixed ratio of the electric charge to the baryon number density are implemented throughout the computation.We find that higher-order correlations incorporate more sensitive critical dynamics than the quadratic ones.In addition,a non-monotonic dependence of the fourth-order correlations between the baryon number and strangeness,i.e.,-χ31BS/χ2Sand χ22BS/χ2S,on the collision energy is also observed. 相似文献