Estimation of the survival function of a repairable standby series system

This article deals with the statistical analysis of an N-component series system supported by an active standby and one repair facility. Assuming that the life and repair times of the components are independent exponential random variables, the probability distribution of the first passage to the system failure time is shown to be a convolution of two independent exponential distributions. Three observation schemes are considered to obtain the maximum likelihood estimates of the survival function. Information matrices are supplied. Numerical results based on Monte Carlo simulation are presented. It is noted that component level information (failure rate, repair rate) is not necessary for estimating the survival function of the system.     

Robust preallocated preferential defense

The problem is to protect a set of T identical targets that may come under attack by A identical weapons. The targets are to be defended by D identical interceptors, which must be preallocated to defend selected targets. The attacker is aware of the number of interceptors, but is ignorant of their allocation. The size of the attack is chosen by the attacker from within a specified range. The robust strategies developed in this article do not require the defender to assume an attack size. Rather, the defender chooses a strategy which is good over a wide range of attack sizes, though not necessarily best for any particular attack size. The attacker, knowing that the defender is adopting a robust strategy, chooses the optimal attack strategy for the number of weapons he chooses to expend. The expected number of survivors is a function of the robust defense strategy and optimal attack strategy against this robust defense.     

An approximation to the stationary distribution of a multiechelon repairable-item inventory system with finite sources and repair channels

We consider a multiechelon repairable-item inventory system where several bases are supported by a central depot. Unlike METRIC-based models, there are only a finite number of repairmen at each base and the depot, and the failure rates at the bases depend on the current number of items online. The principal objective of this article is to develop a quick and accurate approximation to the steady-state distribution of this system. A secondary objective is to compare the solution of this system with a comparable METRIC solution.     

Military spending and economic growth in South Africa

This paper undertakes an empirical analysis of the economic effects of military spending on the South African economy. It estimates a neo‐classical model common in the literature at the level of the macroeconomy and at the level of the manufacturing sector. An attempt is made to improve upon the model by allowing the data to determine the dynamic structure of the model through an ARDL procedure. No significant impact of military spending is found in aggregate, but there is a significant negative impact for the manufacturing sector. This suggests that the cuts in domestic military procurement that have occurred since 1989 could lead to improved economic performance in South Africa through their impact on the manufacturing sector.     

The impact of arms production on the South African manufacturing industry

The 1977 UN arms embargo was one of the main factors which led South Africa to establish a largely self sufficient import‐substituting arms industry capable of meeting the apartheid state's demand for sophisticated weaponry. While macroeconomic studies suggest that high military spending had a damaging effect on economic growth, no studies have investigated the disaggregated impact of military expenditure on industrial development. This paper applies panel data methods to the Industrial Development Corporation's Sectoral Database in order to analyse the level effects of military spending.     

THE ROLLBACK OF LIBYA'S CHEMICAL WEAPONS PROGRAM

In 2003, Libyan leader Muammar Qaddafi agreed to eliminate his country's weapons of mass destruction (WMD) programs and long-range Scud missiles under strict verification by U.S. and British experts and international inspectors. This article examines the negotiation and implementation of Libya's WMD rollback, with a primary focus on its chemical weapons program, and draws some lessons for the future. Although the Libyan case was unique in many ways, some aspects have relevance for other countries, including the critical role played by multilateral nonproliferation organizations, the utility of economic sanctions and export controls, the importance of a flexible U.S. disarmament funding mechanism, the value of rotating technical assistance teams in and out of the country that is disarming, and the desirability of remaining politically engaged with a former proliferator after rollback is complete.