Column generation for stochastic green telecommunication network planning with switchable base stations

We present the green telecommunication network planning problem with switchable base stations, where the location and configuration of the base stations are optimized, while taking into account uncertainty and variability of demand. The problem is formulated as a two‐stage stochastic program under demand uncertainty with integers in both stages. Since solving the presented problem is computationally challenging, we develop the corresponding Dantzig‐Wolfe reformulation and propose a solution approach based on column generation. Comprehensive computational results are provided for instances of varying characteristics. The results show that the joint location and dynamic switching of base stations leads to significant savings in terms of energy cost. Up to 30% reduction in power consumption cost is achieved while still serving all users. In certain cases, allowing dynamic configurations leads to more installed base stations and higher user coverage, while having lower total energy consumption. The Dantzig‐Wolfe reformulation provides solutions with a tight LP‐gap eliminating the need for a full branch‐and‐price scheme. Furthermore, the proposed column generation solution approach is computationally efficient and outperforms CPLEX on the majority of the tested instances. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 351–366, 2016     

On the polyhedral structure of two‐level lot‐sizing problems with supplier selection

In this article, we study a two‐level lot‐sizing problem with supplier selection (LSS), which is an NP‐hard problem arising in different production planning and supply chain management applications. After presenting various formulations for LSS, and computationally comparing their strengths, we explore the polyhedral structure of one of these formulations. For this formulation, we derive several families of strong valid inequalities, and provide conditions under which they are facet‐defining. We show numerically that incorporating these valid inequalities within a branch‐and‐cut framework leads to significant improvements in computation. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 647–666, 2017     

从四渡赤水到脱出金沙

1935年,进入西南地区的中央红军与"追剿"的蒋介石和国民党军展开周旋。国民党军欲一举置红军于死地,红军则要在困境中奋力图存。遵义会议后重新执掌红军领导权的毛泽东,一开始并未找到最适合红军生存的途径。经过几次试探,他很快敏锐意识到红军不能与国民党军展开硬碰硬的较量,而是要审时度势,毅然决然选择最有利的生存道路。一旦固有思维消解,在崇山峻岭、国民党方面又各自为战的西南地区,前路就豁然开朗。最终,红军在金沙江脱出了国民党军的包围圈。这一段历史充分证明,准确估计自己的力量,打破既有思维模式,对政治力量而言,具有何等重要的意义。     

着力抓好科学发展观在基层的全面落实

抓好科学发展观在基层的全面贯彻落实,必须充分认清科学发展观的巨大指导力量,不断激发基层官兵学习实践的内在动力;适应基层官兵特点,不断深化对科学发展观精神实质的理解;实施科学指导,在新的起点上谋求基层学习贯彻科学发展观的最大效益。     

用逆滤波基音同步分析提取声门波的方法

根据语音研究的要求,提出一种运用逆滤波基音同步分析提取声门波的方法,此方法可以比较准确地提取声门波。文中讨论了这种方法的原理、实现及其结果。     

射向保持方案及影响其精度的因素分析

介绍用于压制兵器的射向保持器的工作原理和计算方法,并通过计算机仿真分析了计算机字长,计算步长,仪器安装糟度以及陀螺仪测量精度等因素对射向保持器精度的影响。     

引信发火控制系统环境识别研究

本文通过对影响武器系统终端效能各因素的分析,提出了利用弹道信息对引信炸点实施自适应控制与弹道识别的基本原理及弹道特征量的确定准则,并给出了三种不同的弹道特征量。     

舰艇主动力装置(SMPP)选型的综合评价方法

分析了影响舰艇主动力装置选型的诸要素,考虑了其间的联系与制约,提出了主动力装置选型的综合评价体系与方法.     

任意信号FFT频谱显示误差及消除方法

分析了任意信号FFT、变换频谱在计算机显示中产生误差的原因,介绍了频率轴坐标标定和显示引起的误差对高精度频谱图的影响,指出了无误差显示应满足的条件,并给出了相应的无误差频谱显示程序。     

波速测量层合复合材料冲击损伤实验

在层合复合材料横向冲击试验中,用应变片记录层合板表层在冲击过程中的应变响应,根据波的传播理论和连续损伤力学,从波速变化间接测得冲击下材料的损伤及损伤率。通过实验测得玻璃纤维／环氧（ＧＥ）正交层合板的动态损伤阈值,并证实了ＧＥ复合材料在拉伸阶段比在压缩阶段有更快的损伤扩展速率