An application of servomechanisms to inventory

In recent years, some attention has been devoted to the application of techniques of control theory to inventory management. In particular, H. Vassian (1955) developed a model for a periodic review inventory system utilizing techniques of discrete variable servomechanisms to analyze the system in a cost-free structure. The resulting model is inherently deterministic, however, and emphasizes the control of inventory fluctuation about a safety level by selecting an appropriate order policy. Such an order policy is defined only up to an arbitrary method of forecasting customer demands. The present paper is a continuation of the model developed by Vassian in which exponential smoothing is used as a specific forecasting technique. Full recognition of the probabilistic nature of demand is taken into account and the requirement of minimizing expected inventory level is imposed. In addition, explicit formulas for the variance in inventory are derived as functions of the smoothing constant and the tradeoff between small variance and rapid system response is noted. Finally, in an attempt to remove the bias inherent in exponential smoothing, a modification of that technique is defined and discussed as an alternate forecasting method.     

Linear programming and the reliability of multicomponent systems

Several problems in the assignment of parallel redundant components to systems composed of elements subject to failure are considered. In each case the problem is to make an assignment which maximizes the system reliability subject to system constraints. Three distinct problems; are treated. The first is the classical problem of maximizing system reliability under total cost or weight constraints when components are subject to a single type of failure. The second problem deals with components which are subject to two types of failure and minimizes the probability of one mode of system failure subject to a constraint on the probability of the other mode of system failure. The third problem deals with components which may either fail to operate or may operate prematurely. System reliability is maximized subject to a constraint ori system safety. In each case the problem is formulated as an integer linear program. This has an advantage over alternative dynamic programming formulations in that standard algorithms may be employed to obtain numerical results.     

The Royal Navy and Mine Warfare, 1868-1914

Britain underestimated the importance of the naval mine in the years leading up to the First World War and entered the conflict unprepared for an extended mine campaign. Traditional interpretations of the mine's position are limited and neglect the broader political and economic factors influencing its development. The mine was a peripheral technology representative of the rapid technological change in the period, and its development was affected by financial constraints, international diplomacy and naval administration. Because of structural impediments, however, and despite significant resources devoted to the weapon, the mine faced obstacles which led to both limited stocks and inadequate plans for use at the opening of the First World War.     

THE ‘PRICE’ OF TERRORISM

Security measures are said to increase the price of terrorism. This price has not been hitherto defined in an economically meaningful way. This paper provides a precise definition by treating the terrorists’ resource endowment as a parcel of contingent claims to political influence with a price equal to the summed value of those contingent claims in potential states of the world. Equipped with this definition, an equilibrium model of the price of terrorism is deployed. Important insights are gained into the effect of terrorists’ risk aversion at the level of the price of terrorism in different states of the world and the theoretical conclusion is reached that higher security is associated with a lower price of terrorism rather than a higher price. The implications for policy are discussed.     

Corporate performance and military production in South Africa

With the end of the Cold War and apartheid, a process of demilitarisation and dramatic cuts in military spending has marked the transition to democracy in South Africa. Between 1989 and 1997 the South African defence budget was cut by more than 50% in real terms, with most of the cuts coming from the procurement budget, which was cut by nearly 70% in real terms during the same period. These cuts have had a significant impact on the country's defence industrial base. However, there has been surprisingly little research on the changes to defence companies that have taken place since the late 1980s. This paper makes a start at rectifying that deficiency by providing an analysis of the restructuring of the major defence‐dependent companies over the period 1988–97. It uses a number of financial ratios and other measures of corporate performance to compare their experience with non‐defence companies in the rest of the South African economy during the same period.     

Counter-terrorism in the Horn of Africa: New security frontiers,old Strategies

The US-led ‘war on terror’ dramatically changed America's security strategy towards Africa. But more fundamentally, it threw the Horn of Africa on the centre stage of global counter-terrorism. A double-edged blade, counter-terrorism has at once catalysed peace processes and intensified insecurity, with Islamic radicalism at the core of the regional storm. Governments utilised the threat of terrorism for political ends, defending old security paradigms that prioritised regime stability over human security. Africa integrated counter-terrorism into its emerging security agenda, but insufficient funds, operational constraints and poor coordination with international initiatives have hampered meaningful progress. Washington, laudably, launched a robust counter-terrorist campaign, but its high-handed military-heavy style put fragile democracies at risk while lapses in its overall policy risk triggering proxy wars. This essay examines the impact of counter-terrorism on security in the Horn of Africa. It argues for stronger coordination between national, regional and international initiatives to curb international terrorism.     

LEARNING TO LIVE WITH A NUCLEAR IRAN

Claims that China is the only nuclear power currently expanding its arsenal fail to take into account the technical, historical, and bureaucratic realities that shaped China's nuclear posture and drive its ongoing modernization. China's strategic modernization is largely a process of deploying new delivery systems, not designing new nuclear warheads; the majority of its new missiles are conventionally armed. Today, China maintains the smallest operationally deployed nuclear force of any of the legally recognized nuclear weapon states, operates under a no-first-use pledge, and keeps its warheads off alert. The modernization of China's delivery systems is the culmination of a decades-long plan to acquire the same capabilities deployed by the other nuclear powers. U.S. concerns about this modernization focus too much on deterring a deliberate Chinese attack and ignore the risk that modernized U.S. and Chinese forces could interact in unexpected ways during a crisis, creating uncontrollable escalatory pressures. To manage this risk, Washington should assure Chinese leaders that it does not seek to deny China's deterrent, in exchange for some understanding that China will not seek numerical parity with U.S. nuclear forces.