烟草生产储存火灾危险性及防火对策研究

通过分析烟草生产、储存中的火灾危险性和当前烟草生产、储存时采用的防火措施,对卷烟联合生产工房内储存物料的安全间距、厂房和仓库外搭建雨篷、消防车道和烟草仓库消防设施设计等问题进行了探讨。     

基于综合性能的C3I系统通信效能

论述了C3I的重要性及其效能,分析了影响通信系统性能的因素,力求在实时综合性能的基础上选择通信路由,论述了传统Petri网和模糊Petri网的一些基本概念和特点及其区别,描述了用模糊Petri网进行系统综合性能分析时的有效算法,提出一种基于综合性能的路由选择算法,最后,通过实例来说明通信路由综合性能评价以及路由选择方法.     

Potential and actual arms production: Implications for the arms trade debate

In this paper I develop indices and rankings of potential and actual arms production for about one hundred and fifty countries for data pertaining to the early to mid‐1990s. The countries’ ranked indices are then compared. I find evidence that countries that can produce arms (potential) do produce arms (actual). I also compare the current findings to findings published nine years ago, pertaining to potential and actual arms production in developing nations for the early 1980s. A number of countries then having the potential to produce arms have, in fact, become major arms producers ten years later. The results presented in this paper carry policy implications for the arms trade debate: shall policymakers continue to focus on arms supply restriction and continue to ignore the increasing capacity of developing nations to self‐supply their arms demand?     

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.     

Measuring defense conversion in Russian industry

This paper develops and implements a methodology for quantifying defense conversion in Russian manufacturing in the early 1990s. A two‐sector, three‐good model is employed to analyze the flows of resources from military to non‐military uses and applied to firm‐level survey data under alternative definitions of military production and the MIC. An aggregation framework is constructed to estimate the total quantity and change in Russian military production, the latter decomposed into intrafirm and intersectoral resource reallocation and overall industrial decline. Although there is evidence of substantial decline in military production, the data show little reallocation to productive civilian uses, neither within the MIC nor to other manufacturing sectors.     

Country survey XII: South Africa

This article examines the relationship between defence expenditure and economic performance in South Africa, both prior to and after that country's first fully democratic election in 1994. Prior to 1994 defence expenditure decisions were largely dominated by non‐economic factors; since then defence spending has declined in reaction to, inter alia, the need to address a number of socio‐economic inequities.

After 1975 in particular, military industrialisation in South Africa placed a disproportionately high burden on the country's industrial resources and natural economic and technical capabilities. However, although this suggests that the opportunity cost of domestic arms production has been fairly high, the country's poor economic and development performance since the mid‐1970s is a function of underlying structural deficiencies and institutional constraints rather than the consequence of inordinately high defence spending levels.     

Performance evaluation of a production/inventory system with periodic review and endogenous lead times

This paper considers a discrete time, single item production/inventory system with random period demands. Inventory levels are reviewed periodically and managed using a base‐stock policy. Replenishment orders are placed with the production system which is capacitated in the sense that there is a single server that sequentially processes the items one at a time with stochastic unit processing times. In this setting the variability in demand determines the arrival pattern of production orders at the queue, influencing supply lead times. In addition, the inventory behavior is impacted by the correlation between demand and lead times: a large demand size corresponds to a long lead time, depleting the inventory longer. The contribution of this paper is threefold. First, we present an exact procedure based on matrix‐analytic techniques for computing the replenishment lead time distribution given an arbitrary discrete demand distribution. Second, we numerically characterize the distribution of inventory levels, and various other performance measures such as fill rate, base‐stock levels and optimal safety stocks, taking the correlation between demand and lead times into account. Third, we develop an algorithm to fit the first two moments of the demand and service time distribution to a discrete phase‐type distribution with a minimal number of phases. This provides a practical tool to analyze the effect of demand variability, as measured by its coefficient of variation, on system performance. We also show that our model is more appropriate than some existing models of capacitated systems in discrete time. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

Interval scheduling: A survey

In interval scheduling, not only the processing times of the jobs but also their starting times are given. This article surveys the area of interval scheduling and presents proofs of results that have been known within the community for some time. We first review the complexity and approximability of different variants of interval scheduling problems. Next, we motivate the relevance of interval scheduling problems by providing an overview of applications that have appeared in literature. Finally, we focus on algorithmic results for two important variants of interval scheduling problems. In one variant we deal with nonidentical machines: instead of each machine being continuously available, there is a given interval for each machine in which it is available. In another variant, the machines are continuously available but they are ordered, and each job has a given “maximal” machine on which it can be processed. We investigate the complexity of these problems and describe algorithms for their solution. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

Integrated production scheduling and preventive maintenance planning for a single machine under a cumulative damage failure process

This paper finds the optimal integrated production schedule and preventive maintenance plan for a single machine exposed under a cumulative damage process, and investigates how the optimal preventive maintenance plan interacts with the optimal production schedule. The goal is to minimize the total tardiness. The optimal policy possesses the following properties: Under arbitrary maintenance plan when jobs have common processing time, and different due dates, the optimal production schedule is to order the jobs by earliest due date first rule; and when jobs have common due date and different processing times, the optimal production schedule is shortest processing time first. The optimal maintenance plan is of control limit type under any arbitrary production schedule when machine is exposed under a cumulative damage failure process. Numerical studies on the optimal maintenance control limit of the maintenance plan indicate that as the number of jobs to be scheduled increases, the effect of jobs due dates on the optimal maintenance control limit diminishes. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007