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191.
Luis P. Castro Rita C. Guerra Nguyen Minh Tuan 《Mathematical Methods in the Applied Sciences》2020,43(7):4835-4846
We propose four new convolutions exhibiting convenient factorization properties associated with two finite interval integral transformations of Fourier-type together with their norm inequalities. Moreover, we study the solvability of a class of integral equations of Wiener-Hopf plus Hankel type (on finite intervals) with the help of the factorization identities of such convolutions. Fourier-type series are used to produce the solution formula of such equations, and a Shannon-type sampling formula is also obtained. 相似文献
192.
Sunil Kumar Surath Ghosh Bessem Samet Emile Franc Doungmo Goufo 《Mathematical Methods in the Applied Sciences》2020,43(9):6062-6080
The heat equation is parabolic partial differential equation and occurs in the characterization of diffusion progress. In the present work, a new fractional operator based on the Rabotnov fractional-exponential kernel is considered. Next, we conferred some fascinating and original properties of nominated new fractional derivative with some integral transform operators where all results are significant. The fundamental target of the proposed work is to solve the multidimensional heat equations of arbitrary order by using analytical approach homotopy perturbation transform method and residual power series method, where new fractional operator has been taken in new Yang-Abdel-Aty-Cattani (YAC) sense. The obtained results indicate that solution converges to the original solution in language of generalized Mittag-Leffler function. Three numerical examples are discussed to draw an effective attention to reveal the proficiency and adaptability of the recommended methods on new YAC operator. 相似文献
193.
磁场对非对称量子点中极化子性质的影响 总被引:3,自引:1,他引:3
采用线性组合算符和幺正变换方法研究磁场对非对称量子点中弱耦合磁极化子性质的影响.导出了非对称量子点中弱耦合磁极化子的振动频率、基态能量和基态结合能随量子点的横向和纵向有效受限长度、磁场和电子-声子耦合强度的变化关系.数值计算结果表明:非对称量子点中弱耦合磁极化子的基态能量和基态结合能随量子点的横向和纵向有效受限长度的增加而迅速增大.随回旋频率的增加而增大,随电子-声子耦合强度的增加而减小. 相似文献
194.
为实现电力设备红外图像中目标设备图像的分割,对传统区域生长法需要人工选择初始种子点,以及易产生过分割与欠分割的不足提出了改进,将红外图像中邻域均值最大的像素点作为种子点,实现种子点的自动选取。提出了使用Sobel算子计算梯度幅值作为附加限定条件的生长准则。改进的区域生长法的分割效果比传统的区域生长法效果更好。 相似文献
195.
Hai Zhang 《Journal of Nonlinear Mathematical Physics》2017,24(3):315-327
We introduce Frobenius algebra ?-valued (n, m)th KdV hierarchy and construct its bi-Hamiltonian structures by employing ?-valued pseudo-differential operators. As an illustrative example, the (1, 1)th -valued case is analyzed in detail. Its Hamiltonian structures and recursion operator are derived. Infinitely many symmetries, conservation laws and explicit flow equations are also obtained. 相似文献
196.
This paper is devoted to the construction of weak solutions to the singular constant Q-curvature problem. We build on several tools developed in the last years. This is the first construction of singular metrics on closed manifolds of sufficiently large dimension with constant (positive) Q-curvature. 相似文献
197.
Shaoguang Shi & Zunwei Fu 《分析论及其应用》2021,37(3):347-361
The more explicit decomposition of the operator and the kernel are utilized to investigate a characterization of the central $BMO(\mathbb{R}^{n})$-closure of $C_{c}^{\infty}(\mathbb{R}^{n})$ space via the compactness of the commutators of fractional Hardy operator with rough kernel. 相似文献
198.
A field of endomorphisms R is called a Nijenhuis operator if its Nijenhuis torsion vanishes. In this work we study a specific kind of singular points of R called points of scalar type. We show that the tangent space at such points possesses a natural structure of a left-symmetric algebra (also known as pre-Lie or Vinberg-Kozul algebras). Following Weinstein's approach to linearization of Poisson structures, we state the linearisation problem for Nijenhuis operators and give an answer in terms of non-degenerate left-symmetric algebras. In particular, in dimension 2, we give classification of non-degenerate left-symmetric algebras for the smooth category and, with some small gaps, for the analytic one. These two cases, analytic and smooth, differ. We also obtain a complete classification of two-dimensional real left-symmetric algebras, which may be an interesting result on its own. 相似文献
199.
200.
References: 《理论物理通讯》2007,47(1):31-34
We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of the integration within an order product (IWOP) technique. We also calculate the transition from classical transformation of variables in the states to quantum unitary operator, deduce a new multi-mode squeezing operator, and discuss its squeezing effect. In progress, it indicates that the IWOP technique provides a convenient way to construct new representation in quantum mechanics. 相似文献