激光场特定方向上量子噪声实部和虚部之间的耦合效应

本文用二维气体激光模型对量子噪声的实部和虚部存在耦合的激光场进行了理论分析,利用分离变量法通过福克—普朗克方程导出了振幅在特定方向上的定态激光场强度分布函数的解析式,算出了定态激光强度的平均值,方差和偏斜度,通过计算发现,在特定方向上激光场强度的涨落并不随噪声间的耦合单调变化,它在一定的带宽范围内上下起伏。     

Gradient skewness tensors and local illumination detection for images

In this paper, we propose the definition of D$D$-eigenvalue for an arbitrary order tensor related with a second-order tensor D$D$, and introduce the gradient skewness tensor which involves a three-order tensor derived from the skewness statistic of gradient images. As we happen to find out that the skewness of oriented gradients can measure the directional characteristic of illumination in an image, the local illumination detection problem for an image can be abstracted as solving the largest D$D$-eigenvalue of gradient skewness tensors. We discuss the properties of D$D$-eigenvalues, and especially for gradient skewness tensors we provide the calculation method of its D$D$-eigenvalues and D$D$-characteristic polynomial. Some numerical experiments show its effective application in illumination detection. Our method also presents excellent results in a class of image authenticity verification problems, which is to distinguish artificial “flat” objects in a photograph.     

On the existence of multiply connected monolayered cyclofusenes with given parameters

For a given bipartite graph G its skewness is defined as the difference between the sizes of its classes of bipartition. We show that a multiply connected monolayered cyclofusene with m ≥ 2 internal holes and skewness k exists if and only if 0 ≤ k ≤ 2m − 2, thus settling in affirmative two conjectures raised in a recent paper by Karimi et al.     

Poisson分形过程(英文)

提出了一类叫做Poisson分形过程W(j)H(t)的非Gauss的平稳增量过程,它可以用来研究包括金融和物理等许多领域中的长期依赖性.此过程W(j)H(t)在宽的意义下是自相似的,并且比Gauss过程展现出更厚的尾部.