一类具有饱和发生率的SEIS传染病模型全局稳定性研究

研究一类易感者和潜伏者都有新增常数输入,疾病具有饱和发生率的SEIS传染病模型．经计算得到模型的基本再生数,证明当基本再生数〉1时,模型只存在惟一的地方病平衡点的结论,并利用特征方程和Hurwitz判据分析地方病平衡点的局部稳定性,通过采用第二加性复合矩阵理论证明地方病平衡点的全局渐近稳定性．     

对抗条件下防空武器系统效能评估

空袭和防空是对立存在的。针对现有防空武器系统作战效能评估模型的不足,指出了研究攻防对抗条件下评估防空武器系统作战效能的必要性。通过对防空武器系统与空袭敌机攻防对抗过程的分析,建立了攻防对抗条件下防空武器系统的效能评估模型,借助计算机仿真证明了该模型符合实际作战情况,具有较高的置信度,是对传统防空武器系统效能评估方法的一种完善和补充。     

面向实体的作战行动数据采集系统研究与设计

为满足基地对作战行动数据的实际需求,针对作战行动数据的特点,提出了以作战实体为中心的数据组织方式和作战行动的模板描述方法;运用软件工程技术对系统进行了需求分析和方案设计,并结合主流的web技术构建了系统解决方案。系统能够对训练、演习中的作战行动进行标准化数据描述并记录形成作战行动数据库,为演习评估、裁决等实际应用提供数据支撑。经过长期的数据积累和数据挖掘,能够对部队的作战行动进行合理的评价与预测,为建立长效的数据采集、使用机制提供保障。     

疏通航道反水雷优化模型

为解决疏通航道反水雷作战中的航道选择问题,根据水雷位置确定条件下的反水雷作战特点,运用多目标优化理论建立了与疏通时间最少和雷区航道最短等价的清除水雷数最少和航道倾角绝对值最小疏通航道优化模型。根据疏通航道反水雷作战实际,通过基于完全分层法的单目标模型解算流程、方法,得到优化参数,较好地满足了疏通航道反水雷作战需求。     

NON‐LINEARITY IN THE DEFENCE EXPENDITURE – ECONOMIC GROWTH RELATIONSHIP IN TAIWAN

As we enter the 21st Century, technologies originally developed for defense purposes such as computers and satellite communications appear to have become a driving force behind economic growth in the United States. Paradoxically, almost all previous econometric models suggest that the largely defense‐oriented federal industrial R&;D funding that helped create these technologies had no discernible effect on U.S. industrial productivity growth. This paper addresses this paradox by stressing that defense procurement as well as federal R&;D expenditures were targeted to a few narrowly defined manufacturing sub‐sectors that produced high tech weaponry. Analysis employing data from the NBER Manufacturing Productivity Database and the BEA’ s Input Output tables then demonstrates that defense procurement policies did have significant effects on the productivity performance of disaggregated manufacturing industries because of a process of procurement‐driven technological change.     

ARE USA CITIZENS AT RISK OF TERRORISM IN EUROPE?

This paper analyzes the determinants of the probability of US citizens being victims of terrorist attacks in European countries, taking into account uncontrolled heterogeneity of the data. The analysis employs ITERATE data from February 1968 to December 2002 to ascertain significant characteristics that influence the probability (e.g. location, type of casualties, type of attack, and type of terrorists). To deal with the unobserved heterogeneity a random‐parameter logit model (mixed logit) is used. Some policy implications are presented.     

Defence spending and economic growth in South Africa: A supply and demand model*

This paper provides a contribution to the growing corpus of knowledge and understanding of the interaction between economic growth and defence spending in South Africa by specifying a Keynesian simultaneous equation model and estimating the system for the period 1961 to 1997. The model contains a growth equation, a savings equation, a trade balance equation and a military burden equation and when estimated by single equation and systems estimation methods is relatively well specified. There is evidence of an overall negative effect of military spending on the economy over this period, though the significance of individual coefficients is low. There is certainly no evidence of any positive impact, suggesting that cuts in military spending do present an opportunity for improved macroeconomic performance.     

MILITARY SPENDING AND ECONOMIC GROWTH IN SOUTH ASIA: COMMENT AND RECONSIDERATION

In a recent paper in this journal, Wijewerra and Webb study the connection between military spending and gross domestic product (GDP) in a group of five South Asian countries, finding a small but statistically significant positive relationship between military spending and GDP. This paper reviews their approach and proposes an alternative which tries to deal with the problems of omitted variables and variable construction. It finds, in contrast, that a higher share of military spending in GDP is associated with lower growth of GDP per capita.     

Defense Burden and the Effect of Democracy: Evidence from a Spatial Panel Analysis

ABSTRACT

Do democracies spend less on national defense? This paper provides new evidence of the effect of democracy on defense burden based on a Spatial Durbin Model with panel data for 98 countries for the years 1992–2008. While democracy measured by means of an index variable covering the entire range from perfect democracy to perfect autocracy turns out to be insignificant, dummy variables indicating transition to higher levels of democracy reveal a statistically highly significant negative effect of democracy on a country’s defense burden. Allowing for country-specific effects reveals heterogeneity in the effect of democracy across countries. Apart from the effect of democracy, the estimation results indicate strong spatial dependence of military burdens across countries. Moreover, they provide statistical evidence for a peace dividend, for substitution effects in defense spending and for a negative effect on the military burden for countries when they exhibit a trade surplus instead of a trade deficit.