SOCIAL PREFERENCES FOR NATIONAL DEFENCE AND POLICE ENFORCEMENT IN WESTERN EUROPE

We study the determinants of social preferences for national defence and for police and law enforcement. For this task, we estimate a bivariate ordered probit model for a set of European countries (France, Finland, Norway, Portugal, Spain and Sweden) in 2006. Determinants of spending decisions for defence and police are found to be linked but are of significantly different magnitudes. Besides, measures against terrorist threats are positively linked to police and defence spending increases, while the subjective perception of fiscal pressure has no influence. Finally, no significant differences are found between Northern and Southern Europe.     

The Economic Consequences of the Libyan Spring: A Synthetic Control Analysis

Abstract

In 2011 a wave of revolutionary movements, the so-called Arab Spring, spread in the Middle East and North Africa. Libya was one of the most affected countries, ending Gaddafi’s dictatorship after an international intervention and a civil war. This paper assesses the effects that this revolution had on Libyan economy. The analysis is made by means of the synthetic control method. Our estimates for the 2011–2014 period show (i) a cumulative loss in the growth rate of per capita real GDP of 64.15%; (ii) a cumulative loss in per capita real GDP of 56,548 dollars; and (iii) a cumulative loss in the aggregate real GDP of 350.5 billion dollars.     

Life cycle costs for decision support ‐ a study of the various life cycle costs used at different levels of defence policy and management∗

Debates on many aspects of defence economics ‐ on the scale of defence expenditure, on the allocation of that expenditure to various military capabilities, and on the selection of equipment offering the best value for money ‐ are bedevilled by misunderstandings and misconceptions about the costs of defence equipment. This paper seeks to improve understanding of defence equipment costs by defining a hierarchy of defence equipment within which the direct and indirect life cycle costs of defence equipment may be allocated at different levels. Having reviewed the direct and indirect components of the life cycle cost, this paper then shows how different costing studies for different purposes require different approaches to life cycle costing, and that there is no unique life cycle cost which can be assigned to one particular item of defence equipment. There is instead a range oflife cycle costs, each of which is appropriate for a particular study, and it is important that a quoted cost of an item of defence equipment should be used only in the pertinent circumstances. The paper is written from a UK perspective and accordingly uses British nomenclature, but its principles should be relevant to defence cost studies in other nations.     

一类微分方程Poincaré分岔极限环的不存在性

利用一阶Mel'nikov函数讨论了一类广义Liénard方程Poincaré分岔极限环的不存在性,得出了若干充分条件.     

基于K均值排序方法的频域盲分离算法

针对频域盲分离算法中存在的排序不确定性问题,提出一种基于K-means算法的排序方法。该方法在排序中使用K-means算法对分离子信号进行整体排序,与传统相邻频点排序方法相比,大大提高了盲源分离的鲁棒性。仿真结果表明了该方法的有效性。     

Efficient generation of cycle time‐throughput curves through simulation and metamodeling

A cycle time‐throughput (CT‐TH) curve, which quantifies the relationship of long‐run average cycle time to throughput rate, plays an important role in strategic planning for manufacturing systems. In this paper, a nonlinear regression metamodel supported by queueing theory is developed to represent the underlying CT‐TH curve implied by a manufacturing simulation model. To estimate the model efficiently, simulation experiments are built up sequentially using a multistage procedure. Extensive numerical experiments are presented to demonstrate the effectiveness of the proposed procedure. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

Machine maintenance with workload considerations

Machine maintenance is modeled in the setting of a single‐server queue. Machine deterioration corresponds to slower service rates and failure. This leads to higher congestion and an increase in customer holding costs. The decision‐maker decides when to perform maintenance, which may be done pre‐emptively; before catastrophic failures. Similar to classic maintenance control models, the information available to the decision‐maker includes the state of the server. Unlike classic models, the information also includes the number of customers in queue. Considered are both a repair model and a replacement model. In the repair model, with random replacement times, fixed costs are assumed to be constant in the server state. In the replacement model, both constant and variable fixed costs are considered. It is shown in general that the optimal maintenance policies have switching curve structure that is monotone in the server state. However, the switching curve policies for the repair model are not always monotone in the number of customers in the queue. Numerical examples and two heuristics are also presented. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

环肋轴对称组合壳塑性极限分析的弹性模量调整有限元方法

基于轴对称截锥壳单元,以单元横截面峰值应力为等效应力,建立了弹性模量调整有限元方法,应用Fortran语言编制了有限元软件用于计算环肋轴对称组合壳的塑性极限载荷.该方法根据组合壳的应力分布情况调整轴对称壳单元和肋骨单元的弹性模量,并进行一系列的弹性迭代计算,计算收敛后即可以得到环肋轴对称组合壳的塑性极限载荷.通过对算例的计算证明:该方法具有良好的收敛性和较高的效率,计算结果与试验结果吻合较好.     

Factors influencing the modernization of military-investment economic appraisal systems

Budgetary restrictions resulting from the present international economic crisis have tightened the need to improve efficiency in defense spending, leading to the armed forces having to undertake their duties with fewer resources. Previous reports on the subject have looked into the determining factors and effects of military spending but very few studies have analyzed the determinants for the modernization of the methodology for assessing efficiency. Thus, using a multiple regression statistical model, we have analyzed the appraisal systems in place in 28 countries to identify factors that influence the development of economic assessment of military expenditure. Our findings have revealed three factors that may favor the improvement of appraisal systems with regard to military expenditure: the quality of governance, size of the armed forces, and unemployment levels.