松弛工期窗口指派和截断控制学习效应资源约束单机排序问题

研究松弛工期窗口指派资源约束单机排序问题,决策者需要在一台处理机上连续处理n个独立的任务.每个任务有一个待定的松弛工期窗口,任务的处理时间通过分配资源可控,且是所在位置的递减函数,当函数递减到一定程度时,需要用一个控制参数替换.目的是在可用资源量有限条件下求出任务的处理顺序和工期窗口以及资源分配方案,使得任务中最大费用取最小值.分两步处理:首先将问题转化为非线性凸规划问题,利用凸规划理论求出任务的资源数量;其次通过解指派问题得到任务最优处理顺序,进而求得任务的工期窗口.给出了多项式时间的最优算法,提供一个算例说明算法的有效性和运算过程.     

TWO MEROMORPHIC FUNCTIONS SHARE SOME PAIRS OF SMALL FUNCTIONS WITH TRUNCATED MULTIPLICITIES

Using the techniques proposed in [3], we prove that two nonconstant meromorphic functions f and g on C must be linked by a quasi-Mbius transformation if they share some pairs of small functions with more precise truncated multiplicities, which improve and extend the results of Duc Quang Si.     

Electro-oxidation of Formic Acid on Carbon Supported Edge-Truncated Cubic Platinum Nanoparticles Catalysts

The oxidation of formic acid on edge-truncated cubic platinum nanoparticles/C catalysts is investigated. X-ray photoelectron spectroscopy analysis indicates that the surface of edge-truncated cubic platinum nanoparticles is composed of two types of coordination sites. ＇/＇he oxidation behavior of formic acid on edge-truncated cubic platinum nanoparticles/C is investigated using cyclic voltammetry. The apparent activation energies are found to be 54.2, 55.0, 61.8, 69.5, 71.9, 69.26, 65.28k J/tool at 0.15, 0.3, 0.4, 0.5, 0.6, 0.65, 0.7V, respectively. A specific surface area activity of 1.76 mA·cm^-2 at 0.4 V indicates that the edge-truncated cubic Platinum nanoparticles are a promising anode catalyst for direct formic acid fuel cells.     

随机截断下PL估计的强表示式

本文在随机左截断情形下,研究了分布函数不连续时,分布函数的乘积限估计（PL估计）Fn(x）的一致强表示式,得到与分布函数连续情形下相同的结果。     

含有截断和缺失数据的经验似然推断

本文将经验似然的方法应用到同时包含截断和缺失数据的情况. 通过定义调整后的经验似然比, 证明它服从$\chi^2$分布. 利用随机模拟, 比较经验似然和正态方法的优劣. 结果发现经验似然方法在很多情况下都优于正态方法.     

Intermittency and Thermalization in Turbulence

A dissipation rate, which grows faster than any power of the wave number in Fourier space, may be scaled to lead a hydrodynamic system to actually or potentially converge to its Galerkin truncation. Actual convergence here means the asymptotic truncation at a finite wavenumber kc above which modes have no dynamics; and, we define potential convergence for the truncation at kG which, however, grows without bound. Both types of convergence can be obtained with the dissipation rate μ[cosh（k/kc） - 1] that behaves as k2 （newtonian） and exp{k/kc} for small and large k/kc respectively. Competing physics of cascade, thermalization and dissipation are discussed for numerical Navier-Stokes turbulence, emphasizing the intermittency growth issue.     

散焦模糊图像复原的截断奇异值分解算法

在反射边界条件假设下,导出了散焦和噪声所导致的图像降质的离散延拓模型,给出了延拓模型的卷积方程及相应的卷积算子;通过引进延拓矩阵的Fourier变换证明了该卷积算子的相关性质并导出了该卷积算子的奇异系,给出了一个解决散焦模糊图像复原的截断奇异值分解算法及算法的计算步骤.图像复原的数值实验实例表明了该算法的有效性.     

Fast local reconstruction by selective backprojection for low dose in dental computed tomography

The high radiation dose in computed tomography （CT） scans increases the lifetime risk of cancer, which becomes a major clinical concern. The backprojection-filtration （BPF） algorithm could reduce the radiation dose by reconstructing the images from truncated data in a short scan. In a dental CT, it could reduce the radiation dose for the teeth by using the projection acquired in a short scan, and could avoid irradiation to the other part by using truncated projection. However, the limit of integration for backprojection varies per PI-line, resulting in low calculation efficiency and poor parallel performance. Recently, a tent BPF has been proposed to improve the calculation efficiency by rearranging the projection. However, the memory-consuming data rebinning process is included. Accordingly, the selective BPF （S-BPF） algorithm is proposed in this paper. In this algorithm, the derivative of the projection is backprojected to the points whose x coordinate is less than that of the source focal spot to obtain the differentiated backprojection. The finite Hilbert inverse is then applied to each PI-line segment. S-BPF avoids the influence of the variable limit of integration by selective backprojection without additional time cost or memory cost. The simulation experiment and the real experiment demonstrated the higher reconstruction efficiency of S-BPF.     

复变函数中刘维尔定理的新证明

利用截断函数的性质给出了复变函数中刘维尔定理的一种新的证明方法.     

多层介质中逆热传导问题的傅里叶正则化方法

逆热传导问题是数学物理反问题中的热点和前沿课题之一,在钢铁生产等领域中具有重要的应用背景.讨论一个多层介质中的逆热传导问题,它是一个极度不适定问题.通过傅里叶截断方法构造正则化近似解,并给出相应的稳定性估计.