C4ISR系统领域分析与需求复用方法研究

重用作为一种领域模型的构建方法,可以快速构成一个有效的需求模型。分析了C4ISR系统军事需求模型的领域性及其需求共性,进而对比研究了C4ISR系统军事建模过程中的重用方法,为C4ISR系统军事需求开发中解决共性需求问题提供思路。     

Optimal inventory control policy for periodic‐review inventory systems with inventory‐level‐dependent demand

We consider a setting in which inventory plays both promotional and service roles; that is, higher inventories not only improve service levels but also stimulate demand by serving as a promotional tool (e.g., as the result of advertising effect by the enhanced product visibility). Specifically, we study the periodic‐review inventory systems in which the demand in each period is uncertain but increases with the inventory level. We investigate the multiperiod model with normal and expediting orders in each period, that is, any shortage will be met through emergency replenishment. Such a model takes the lost sales model as a special case. For the cases without and with fixed order costs, the optimal inventory replenishment policy is shown to be of the base‐stock type and of the (s,S) type, respectively. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012     

云模型及其在指挥控制系统可靠性分析中的应用

根据指挥控制系统的特点及作战应用的具体情况,从指挥控制系统的可靠性出发,提出了适合指控系统可靠性分析的云模型。通过拟定性能评价指标,导出各指标的云模型及其多维加权综合云的重心,应用云重心评价方法进行分析;并通过案例,运用基于PC-L INM AP的云重心评价方法,以影响指挥控制系统可靠性的两个重要性能指标为依据,分析了未来联合作战中指挥控制系统的可靠性,比较贴近作战实际,可信度较高。     

误差配准在两种纯距离定位算法的应用比较

组网雷达系统中,由于观测信息量的增加,对目标存在多种定位算法。很多情形下,误差配准公式是基于某一定位算法推导而来,误差配准的结果也相应的用来提高此定位算法的定位精度。定位算法的复杂程度不同导致基于此算法推导误差配准公式难度不一致,不同定位算法的定位精度也不尽相同。因此,对两种多距离定位算法的定位精度、误差配准推导难易程度进行了理论分析和仿真计算,给出了定位精度的解析表达式和仿真结果。利用表达式简单的定位算法推导基于最小二乘的误差配准公式,并将误差配准结果反馈给定位精度高的定位算法,以最大程度提高误差配准结果的应用效果,减轻计算复杂度,提高信息的利用度。     

组网雷达的改进粒子滤波算法

针对现代战争中有源雷达容易受到干扰和反辐射导弹的摧毁,以及无源雷达隐蔽性高,只能测量方位角度,测量精度小等特点,提出利用集中式有源雷达系统与无源雷达系统协同组网对目标进行跟踪。但是在实际环境中,噪声属性以及有源雷达,无源雷达接收信号的特点决定了组网雷达需要应用非线性滤波技术对信号进行处理。传统的非线性技术包括卡尔曼滤波、扩展卡尔曼滤波(EKF)或无迹卡尔曼滤波(UKF)等方法。非线性近似过程带来的误差相对较大,而且均要求观测噪声和过程噪声为独立或相关的高斯白噪声。而粒子滤波避免了传统非线性滤波方法的缺陷,但是存在粒子退化,于是用EKF和UKF在每一时刻更新粒子,用更新的粒子及其协方差构造重要性函数,然后重采样。仿真实验表明这两种改进粒子滤波方法有很好的效果。     

美国2014年《四年防务评估报告》特点

2014年3月4日,美国国防部向国会提交了2014年版《四年防务评估报告》和《2015财年国防预算报告》。《四年防务评估报告》更新了再平衡战略,为美军建设提出了优先发展方向,要求美军联合部队向“更小型化”转型,以满足未来军事行动需求。     

舰艇雷达隐身及雷达散射截面预估研究

分析了舰艇雷达隐身的原理和方法,论述了舰艇外形对雷达散射截面的影响,提出了建立舰艇雷达散射截面预估程序的基本思想．     

舰用燃气轮机起动失效分析

以舰用燃气轮机为对象,在简述燃气轮机起动过程的基础上,分析其起动失效的各种原因,提出解决的方法,为燃气轮机的操作及维护提供参考．     

Does Military Spending Nonlinearly Affect Economic Growth in South Africa?

Using annual data collected from 1988 to 2015, this study provides evidence of a non-linear relationship between military spending, economic growth and other growth determinants for the South African economy. The empirical study is based on estimates of a logistic smooth transition regression (LSTR) model and our empirical results point to an inverted U-shaped relationship between military spending and economic growth for the data. Furthermore, our empirical results suggest that the current levels of military spending, as a component of total government expenditure, are too high in the South African economy and need to be transferred towards more productive non-military expenditure in order to improve the performance of economic growth and other growth determinants.     

A cooperative interference resource allocation method based on improved firefly algorithm

To deal with the radio frequency threat posed by modern complex radar networks to aircraft, we researched the unmanned aerial vehicle (UAV) formations radar countermeasures, aiming at the solution of radar jamming resource allocation under system countermeasures. A jamming resource allocation method based on an improved firefly algorithm (FA) is proposed. Firstly, the comprehensive factors affecting the level of threat and interference efficiency of radiation source are quantified by a fuzzy comprehensive evaluation. Besides, the interference efficiency matrix and the objective function of the allocation model are determined to establish the interference resource allocation model. Finally, A mutation operator and an adaptive heuristic are integtated into the FA algorithm, which searches an interference resource allocation scheme. The simulation results show that the improved FA algorithm can compensate for the deficiencies of the FA algorithm. The improved FA algorithm provides a more sci-entific and reasonable decision-making plan for aircraft mission allocation and can effectively deal with the battlefield threats of the enemy radar network. Moreover, in terms of convergence accuracy and speed as well as algorithm stability, the improved FA algorithm is superior to the simulated annealing algorithm (SA), the niche genetic algorithm (NGA), the improved discrete cuckoo algorithm (IDCS), the mutant firefly algorithm (MFA), the cuckoo search and fireflies algorithm (CSFA), and the best neighbor firefly algorithm (BNFA).