Control charts for exponentially distributed product life

This paper introduces a special control chart procedure for exponentially distributed product life. Statistical control of product life in manufacturing requires continuing life tests of manufactured product so as to detect changes in product life and take appropriate corrective action. These life testing experiments may become exceedingly time consuming and thus can be both impractical because of serious time delays in implementing corrective action on the process when indicated, and quite uneconomical. It is desirable to inquire into the character of life testing by means of a control chart procedure based on the real time to first failure within given samples. Measuring the real minimum life provides a considerable reduction in duration of the testing procedure and in the number of specimens destroyed, yielding a considerable economy over the Shewhart's X control chart.     

A generalized model for the economic design of x̄control charts for production systems with increasing failure rate and early replacement

This article generalizes the model for the economic design of x̄-control charts of Duncan [4], starting from the more recent papers of Lorenzen and Vance [8] and Banerjee and Rahim [3]. The classical model of Duncan [4] and its several extensions including the unified model of Lorenzen and Vance [8] assumed exponentially distributed in-control periods and provided uniform sampling schemes. Banerjee and Rahim [3], however, assumed a Weibull-distributed in-control period having an increasing failure rate and used variable sampling intervals. The present article is an extension of the work of Banerjee and Rahim [3], where a general distribution of in-control periods having an increasing failure rate is assumed and the possibility of age-dependent repair before failure is considered. Several different truncated and nontruncated probability models are chosen. It is proposed that economic benefits can be achieved by adopting a nonuniform inspection scheme and by truncating a production cycle when it attains a certain age. Numerical examples are presented to support this proposition. Finally, the effect of model specification in the choice of failure mechanism is investigated. © 1993 John Wiley & Sons, Inc.     

Whose Hearts and Whose Minds? The Curious Case of Global Counter-Insurgency

Traditionally regarded as a secondary activity in military thinking and practice, the notion of counter-insurgency (COIN) has undergone a remarkable renaissance. This analysis traces the origins of this renaissance to two distinctive schools: a neo-classical school and a global insurgency school. The global insurgency school critiques neo-classical thought and presents itself as a more sophisticated appreciation of current security problems. An examination of the evolution of these two schools of counter-insurgency reveals how the interplay between them ultimately leaves us with a confused and contradictory understanding of the phenomenon of insurgency and the policies and strategies necessary to combat it.     

Gas and the North‐West Frontier

John Terraine, Business in Great Waters: The U Boat Wars 1916 ‐1945. London: Leo Cooper, 1989. Pp.xx + 841; £19.50.

Peter Simkins, Kitchener's Armies: The Raising of the New Armies, 1914–16. Manchester: Manchester University Press, 1988. Pp.xvi + 359; index; illustrations. £37.50 (hardback).

Keith Grieves, Sir Eric Geddes: Business and Government in War and Peace. Manchester and New York: Manchester University Press, 1989. Pp.xiv + 188; £35.

Jeffrey Grey, The Commonwealth Armies and the Korean War: An Alliance Study. Manchester: Manchester University Press, 1988. Pp.xii + 244; £12.95.

Rajan Menon and Daniel N. Nelson (eds.), Limits to Soviet Power. Lexington, MA/Toronto: Lexington Books, 1989. Pp.vii + 231; $35.

Michael Leifer, ASEAN and the Security of South‐East Asia. London and New York: Routledge, 1989. Pp.x + 198; £30.

Grant Wardlaw, Political Terrorism: Theory, Tactics and Counter‐measures. Cambridge: Cambridge University Press, second edn. 1989. Pp.xv + 248; £27.50 (hardback); £10.95 (paperback).

John F. Murphy, Punishing International Terrorists: The Legal Framework for Policy Initiatives. Totowa, NJ: Rowman &; Allanheld 1985. Pp.x + 142; $25.95.

Hanns Maull and Otto Pick (eds.), The Gulf War. London: Pinter Publishers, 1989. Pp.193; £30.

Royal United Services Institute for Defence Studies and Brassey's Defence Yearbook 1989. London: Brassey's Defence Publishers, 1989. Pp.xxviii + 361; £35.

Virginia Gamba‐Stonehouse, Strategy in the Southern Oceans: A South American View. London: Pinter Publishers, 1989. Pp.xiii + 155; £30.

Ola Tunander, Cold Water Politics: The Maritime Strategy and Geopolitics of the Northern Front. London: Sage Publications for the International Peace Research Institute, Oslo, 1989. Pp.194; £25.

Richard Fieldhouse and Shunji Taoka, Superpowers at Sea: An Assessment of the Naval Arms Race. Oxford: Oxford University Press for SIPRI, 1989. Pp.183; £19.50.

Kenneth E. Boulding, Conflict and Defense: A General Theory. University Press of America, 1988. Pp.xiv + 347; $16.75 (paperback). (First Published, 1962).     

The origin of internal security in Colombia: Part I — A CIA special team surveys La Violencia, 1959–60

In October 1959 the Eisenhower administration dispatched a CIA Special Team to survey the violence problem in Colombia. This article, part one of a two‐part series, examines this first significant attempt by a US administration to influence that nation's internal security situation. It investigates the Special Team's actions and analyses its recommendations for transforming Colombia's conventionally‐orientated security forces. The Team's survey, which focuses on counter‐insurgency tactics, civil action, intelligence operations, psychological warfare, and covert action, is the foundation from which Colombia's modern internal security structures are derived.     

An alliance between Cyprus and Greece: assessing its partners’ relative security contribution

The issue that this paper tackles is the assessment of the relative security benefits that Cyprus and Greece derive in the context of their cooperation on defence matters. This form of cooperation, known as the ‘Integrated Defence Space Doctrine’, aims at defending their interests in the Aegean Sea and the broader East Mediterranean theatre. The paper relies heavily on earlier research on this topic, which deals with the Greek–Cypriot alliance facing an arms race against Turkey, and uses a coefficient especially designed to assess the optimal levels of security and the associated defence expenditure of the two allies. A comparison of the relative security coefficient values for the two allies suggests that the security benefit that Greece derives thanks to its alliance with Cyprus exceeds the corresponding Cypriot benefit by far. Given the importance assigned to human resources by this index, in conjunction with the demographic problems of Greece, this conclusion justifies the recent Greek defence policy revision, emphasizing quality, capital equipment and flexibility of forces. This revision aims at satisfying the security requirements of the alliance and the increasing demands of an arms race against Turkey.     

Labor staffing and scheduling models for controlling service levels

The problems of labor staffing and scheduling have received substantial attention in the literature. We introduce two new models of the labor staffing and scheduling problems that avoid the limitations of existing models. Collectively, the models have five important attributes. First, both models ensure the delivery of a minimally acceptable level of service in all periods. Second, one model can identify the least expensive way of delivering a specified aggregate level of customer service (the labor staffing problem and a form of labor scheduling problem). Third, the other model can identify the highest level of service attainable with a fixed amount of labor (the other form of the labor scheduling problem). Fourth, the models enable managers to identify the pareto relationship between labor costs and customer service. Fifth, the models allow a degree of control over service levels that is unattainable with existing models. Because of these attributes, which existing models largely do not possess, we expect these models to have broad applicability in a wide range of organizations operating in both competitive and noncompetitive environments. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 719–740, 1997