基于素数的混沌伪随机数发生器的安全性分析

分析了一类基于素数的混沌伪随机数发生器的安全性问题。分析表明,此类混沌伪随机数发生器的输出不是密码学安全的伪随机序列,在截获不长的一段序列的基础上即可很容易地恢复此类PRNGs的全部密鈅。虽然基于素数的方法在改善混沌序列相关性能、周期长度等方面具有一定的优势,但是却不能增加序列的不可预测性,这就限制了此类混沌伪随机数发生器在诸多应用领域中的应用前景。     

一类具有饱和发生率的离散型SIS传染病模型的全局渐近稳定性

研究一类具有饱和发生率的离散型SIS传染病模型,得到模型的基本再生数.通过比较原理以及构造适当的Lyapunov函数,证明当基本再生数R01时,无病平衡点是全局渐近稳定的;当基本再生数R01时,地方病平衡点是全局渐近稳定的.     

一类具有饱和发生率的离散型SIS传染病模型

研究一类具有饱和发生率的离散型SIS传染病模型,得到了模型的基本再生数.通过线性化的方法,运用LaSalle-Lyapunov定理,证明当基本再生数R01时,无病平衡点是全局渐近稳定的;通过迭代的方法,证明当基本再生数R01时,地方病平衡点是全局渐近稳定的.     

基于理想点距离算法的灭火作战方案优选

分析了传统的灭火作战方案优选方法存在的弊端,提出了基于模糊集理论的计算理想点距离的优选法,明确了语言变量与模糊集理论的相关定义,规定了模糊评价语言与三角模糊数的换算方法,阐述了理想点距离的计算方法,建立了灭火作战方案优选模型,验证了该方法在灭火作战方案优选方面的科学性、有效性以及合理性.     

刍议英文电影在大学英语课堂教学中的运用

在英语课堂教学中运用英文电影,可为学生提供丰富的语境化的语言和真实的跨文化信息,为学生创造在课堂上实践语言的机会,也更能激发学生的英语学习兴趣。分析在非英语专业学生课堂教学中选择英文电影的标准,探讨电影观前、观看和观后三个阶段的教学活动。     

Exact algorithms for integrated facility location and production planning problems

We consider a class of facility location problems with a time dimension, which requires assigning every customer to a supply facility in each of a finite number of periods. Each facility must meet all assigned customer demand in every period at a minimum cost via its production and inventory decisions. We provide exact branch‐and‐price algorithms for this class of problems and several important variants. The corresponding pricing problem takes the form of an interesting class of production planning and order selection problems. This problem class requires selecting a set of orders that maximizes profit, defined as the revenue from selected orders minus production‐planning‐related costs incurred in fulfilling the selected orders. We provide polynomial‐time dynamic programming algorithms for this class of pricing problems, as well as for generalizations thereof. Computational testing indicates the advantage of our branch‐and‐price algorithm over various approaches that use commercial software packages. These tests also highlight the significant cost savings possible from integrating location with production and inventory decisions and demonstrate that the problem is rather insensitive to forecast errors associated with the demand streams. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

Monitoring the market or the salesperson? The value of information in a multilayer supply chain

We study a supply chain in which a manufacturer relies on a salesperson to sell the products to the consumers. The sales outcome is determined by a random market condition and the salesperson's service level, both of which are privately observed by the salesperson. Apart from them, there are two types of resellers: a knowledgeable reseller observes the market condition, whereas a diligent reseller can monitor the service level. While delegating to a reseller enhances information acquisition, it may also result in double marginalization and inefficiency. We identify several operating regimes in which double marginalization can be eliminated via simple contracts and establish the benefit of monitoring the salesperson over monitoring the market. Our dominance result is not prone to our model characteristics regarding the complementarity of market condition and sales effort, the relative importance of adverse selection and moral hazard, and the contract form. We then generalize our model and re‐establish the dominance result in the presence of reseller's risk aversion or private monitoring expertise. We also quantify the performance gaps among different selling schemes under various scenarios. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

准确界定马克思主义中国化的历史进程

马克思主义中国化经历第一次历史性飞跃及其第一大理论成果毛泽东思想和第二次历史性飞跃及其第二大理论成果中国特色社会主义理论体系两个大阶段,在第一个大阶段中,经历新民主主义革命理论、社会主义革命理论和社会主义建设理论三个小阶段,在第二个大阶段中,经历邓小平理论、“三个代表”重要思想和科学发展观重大战略思想等若干个小阶段。     

基于整数规划的地地导弹打击目标优化选取

地地战役战术导弹火力运用中,对导弹打击目标的选取是导弹部队制定合理科学作战方案所面临的现实问题。针对给定弹量和特定作战意图对打击目标进行优化选择问题,运用0-1型整数规划,建立合理的数学模型并确定最优打击目标。通过应用实例表明,此方法简便易行,可操作性较强,具有一定的实用价值。     

多址通信的跳频码序列的研究

在跳频多址通信中,为了减少用户之间的互相干扰,保证良好的同步以及其它工作性能,要求跳频码序列具有较好的互相关特性和自相关特性。本文首先分析了具有较好互相关特性和自相关特性的码序列的理论上受到的限制,然后着重分析了它们的构造和产生。