求解带组换装时间单机调度问题的禁忌搜索算法

以包头某钢铁线材企业生产实际调度问题为背景,研究了一类带组换装时间的单机调度问题.由于该问题是NP难的,本文提出了一类适合该问题的禁忌搜索算法.此外,本文将问题性质引入了禁忌搜索算法以进一步提高算法寻优性能,降低算法运行时间.本文提出的算法在随机问题和实际问题上均进行了测试,实验结果表明,本文提出的算法能在不到10秒的时间内获得实际问题的一个近似最优解.     

Some notes on a conjecture of Zygmund

In this paper, some classes of differentiation basis are investigated and several positive answers to a conjecture of Zygmund on differentiation of integrals are presented.     

A COMPOUND POISSON MODEL FOR LEARNING DISCRETE BAYESIAN NETWORKS

We introduce here the concept of Bayesian networks, in compound Poisson model, which provides a graphical modeling framework that encodes the joint probability distribution for a set of random variables within a directed acyclic graph. We suggest an approach proposal which offers a new mixed implicit estimator. We show that the implicit approach applied in compound Poisson model is very attractive for its ability to understand data and does not require any prior information. A comparative study between learned estimates given by implicit and by standard Bayesian approaches is established. Under some conditions and based on minimal squared error calculations, we show that the mixed implicit estimator is better than the standard Bayesian and the maximum likelihood estimators. We illustrate our approach by considering a simulation study in the context of mobile communication networks.     

基于保序回归估计的最大耐受剂量确定方法

I期临床试验研究的主要目标之一是评估药物在不同剂量水平下的毒性, 并且建议一个对病人既安全又有效的剂量, 即最大耐受剂量(MTD). 本文针对拓展的up-and-down设计, 进一步给出其基于保序回归估计的最大耐受剂量确定方法. 经大量模拟, 结果表明: 基于保序回归估计的最大耐受剂量确定方法对推荐MTD的准确性和精确度, 以及保护病人, 防止病人暴露在较高毒性剂量水平下方面实现了有意义的改善.     

次模函数近似算法求最小颜色生成树

给定图G并对其进行边着色,G的最小颜色生成树（MCST）问题是指,找出G的一棵生成树,使得其边集所着颜色数最少.最小颜色生成数问题MCST已被证明是NP-、APX-完备的,从而此问题没有近似比为常数的近似算法.本文中,我们利用次模函数理论（贪婪算法的思想）给出最小颜色生成树问题的一个近似算法,且此算法的近似比为最好结果.     

一种求非负不可约三对角矩阵最大特征值的方法

就非负不可约三对角矩阵,给出了一种求最大特征值的方法,关键是求迭代因子g的新方法,且证明了此迭代因子大于文献[2]中的迭代因子(r+3d)/(r+2d),从而减少了迭代次数,节约了运算时间.     

基因识别问题及其算法实现

从大量的DNA序列中获取丰富的生物信息具有重要的理论意义和应用价值.计算得到了Z-curve与Voss两种映射下功率谱与信噪比的理论关系,而且通过核苷酸频数分布快速计算实数映射时的信噪比;提出了4种阈值确定方法和三个评价准则对不同的物种基因阈值进行了分析,累积概率分布交叉阈值法较其他方法最优;分析了固定长度窗口滑动法由于存在"毛刺"问题而造成预测精度下降,在此基础上提出了变步长阶梯平滑滑动法,与固定长度窗口滑动法相比较预测准确率提高了12.16%达到83%,同时还预测了6个未知序列的编码区域.     

An alternating iterative method and its application in statistical inference

This paper studies non-convex programming problems. It is known that, in statistical inference, many constrained estimation problems may be expressed as convex programming problems. However, in many practical problems, the objective functions are not convex. In this paper, we give a definition of a semi-convex objective function and discuss the corresponding non-convex programming problems. A two-step iterative algorithm called the alternating iterative method is proposed for finding solutions for such problems. The method is illustrated by three examples in constrained estimation problems given in Sasabuchi et al. （Biometrika, 72, 465472 （1983））, Shi N. Z. （J. Multivariate Anal., 50, 282-293 （1994）） and El Barmi H. and Dykstra R. （Ann. Statist., 26, 1878 1893 （1998））.     

连续对策的最大熵策略密度对策解

对于正方形[0,2]×[0,2]上的连续对策,将局中人的非纯策略(概率分布函数)的导数称为这个局中人的策略密度(概率密度函数).建立了这种连续对策的最大熵理论.主要证明了当每个局中人都没有最优纯策略时,具有最大熵的最优策略密度集合的非空紧凸性,研究了最优策略密度的最大熵,给出一类带有最大熵的连续对策.     

Ultraslow Propagation of Entangled State via Four-Wave Mixing in a Coupled Double Quantum Well

An analytical method based on four-wave mixing （FWM） is here developed to study the generation of entangled state in an asymmetric semiconductor double quantum well structure. It is found that the maximally entangled state of two beams （the probe and four-wave mixing beams） can be achieved in an appropriate condition. Moreover, we also show that the two entangled beams propagate with ultraslow group velocity in the semiconductor medium. This investigation can be used for achieving the entangled beams in the semiconductor solid-state medium, which is much more practical than that in an atomic medium because of its flexible design and the wide adjustable parameters.