Does defence expenditure have a spillover effect on income inequality? A cross-regional analysis in China

China’s defence expenditure has been growing rapidly along with GDP growth during the past two decades. Meanwhile, the income gap has continued to increase. There are conflicting views regarding whether the defence expenditure is capable of reducing income inequality. Therefore, this paper investigates the existence of any spillover effect of defence expenditure on income inequality, with a special focus on the regional differences among 31 provinces and 7 military regions in China. We extend panel cointegration and the impulse response function by using panel data during the period of 1997–2012. The empirical results show that the defence expenditure has an impact on income inequality, and the effect varies over different regions in China. The defence expenditure has a spillover effect on income inequality in the full sample panel and the southeastern panel. An increase in the defence expenditure does not crowd out social welfare spending due to the high level of economic development and government expenditure. On the contrary, in the northern panel, the effect is opposite because of the unbalanced economic development levels within the panel. Beijing as the capital of China, benefits more from the expansion of defence expenditure thus widening the income gap. In addition, the impulse response analyses further confirm a stronger effect of the defence expenditure on income inequality in the northern and the southeastern panels over a short period.     

Minimizing sums and products of linear fractional functions over a polytope

In this paper, we develop efficient deterministic algorithms for globally minimizing the sum and the product of several linear fractional functions over a polytope. We will show that an elaborate implementation of an outer approximation algorithm applied to the master problem generated by a parametric transformation of the objective function serves as an efficient method for calculating global minima of these nonconvex minimization problems if the number of linear fractional terms in the objective function is less than four or five. It will be shown that the Charnes–Cooper transformation plays an essential role in solving these problems. Also a simple bounding technique using linear multiplicative programming techniques has remarkable effects on structured problems. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 583–596, 1999     

卫星导航抗干扰接收机信道大动态范围通用设计方法研究*

为适应“导航战”下的强干扰输入,导航接收机对模拟信道的动态范围提出了更高的要求。在给定的信噪比恶化容限约束下,原有的分析方法给出了二维曲线分析模型,得到了动态范围的优化设计及各级增益划分方法,但仅适用于输出功率基本不变的AGC电路。基于增加的AGC输出回退功率这一参数,论文提出了一种三维曲面求解模型,揭示了各电路参量与模拟信道动态范围的约束关系,可适用于输出功率变化的AGC电路,以实现更高的动态范围。针对三维模型中参数求解复杂的问题,利用纯衰减网络的特性将复杂的数值求解简化为直线求解,大幅降低了设计复杂度。在给出的设计实例中,动态范围测试结果与设计预期吻合较好,验证了方法的正确性。     

基于改进GM(1,1)模型的导弹贮存可靠性预测方法

针对导弹系统技术复杂、贮存样本量受限、测试数据波动性较大等特点,结合装备的具体情况提出了基于改进GM(1,1)模型的导弹贮存可靠性预测方法。该方法首先利用"对数-幂函数变换"对导弹的历史可靠性数据进行处理,提高数据光滑度,然后依据GM(1,1)模型计算得到可靠性预测值和残差,再利用残差建立残差修正模型,得到残差修正值,减少残差对结果的影响,最后利用残差修正值修正可靠性预测值并还原,求得可靠性最终预测值。实例表明,该改进模型对导弹系统可靠性变化的描述比传统模型更加准确有效,预测结果精度更高,为导弹贮存可靠性预测分析提供了一种有效的改进方法,其算法设计推广性强,可作为其他装备寿命预估的重要工具。     

基于“综合赋权”模糊物元模型的机场运行安全评价

为了保证机场运行安全,防止事故的发生,依据模糊物元分析理论,结合机场运行安全评价指标体系,构建了基于综合赋权的机场系统模糊物元安全评价模型。在该模型中,通过层次分析法和熵值法主客观综合所确定的权重,为指标体系进行线性加权,实现综合赋权,从而将计算得到的综合权重用于模糊物元建模与评价。实例分析结果表明,该模型步骤简单,过程科学合理,并兼顾了主客观因素的影响,评价结果总体反映了机场的真实安全水平,也为机场安全的科学评价提供了新思路。     

一种针对分布式MIMO雷达的高效干扰功率分配方法

MIMO雷达的种类很多,其中分布式MIMO雷达是具有空间分集特性的一种,具有较强的代表性。针对采用多波束多信号干扰设备干扰分布式MIMO雷达的情况,要考虑针对MIMO雷达各节点干扰功率的分配问题,提出了采用能量集中法进行功率分配。给出分配方法及干扰效果的仿真实验,结果表明在使用相同的干扰功率情况下,所讨论的方法比传统的干扰等比例分配法具有更佳的干扰效果。     

无源雷达截获概率建模与窗口变量影响仿真

在截获概率概念和截获条件的基础上,综合时域、空域、频域等窗口函数构建截获概率模型,分别建立截获过程的4个窗口函数子模型,研究截获概率与窗口函数变量的影响关系。以SPS-48雷达为辐射源,仿真分析各窗口函数变量对截获概率的影响程度,讨论分区策略下无源雷达参数优化对截获概率的影响并总结截获概率提高方法,为无源雷达设计、研制、试验以及使用提供技术支撑。     

光流算法研究

光流的测量是视频序列处理和视频挖掘中的基本问题。首先简述了光流法的基本原理,即物体亮度不变特性;然后阐述了计算光流的4类算法:微分方法、区域匹配方法、基于能量的方法和基于相位的方法,并对当前主流的能量算法进行了详细探讨;最后对各种光流算法的评测方法与测试集进行了说明。     

计数序贯抽样检验方案的OC函数和ASN

根据序贯概率比检验的理论,给出计数序贯抽样检验方案的设计原理,得到国家标准GB／T8051—2008中计数序贯抽样检验方案的OC函数和ASN的计算方法。     

一种鱼雷自导信号频率检测方法研究

靶场在进行智能鱼雷鉴定试验任务时,实时准确地检测出鱼雷自导信号的频率成分是靶标信号处理中的重要环节,谱线比值法便是靶标进行信号处理时检测信号频率的一种有效方法。本文介绍了谱线比值法的基本原理,针对目前鱼雷自导信号特点,对该方法提出了改进方案并进行了仿真。仿真结果表明,经改进的谱线比值法能够满足靶标检测复杂鱼雷自导信号体制下信号频率的使用要求。