A note on a difficulty inherent in estimating reliability from stress–strength relationships

This note calls attention to a difficulty which arises frequently in the application of stress-strength methods in reliability theory. This difficulty has led to unanticipated catastrophic failures in a number of applications.     

Comparison of stochastic processes used in sonar detection models

In any model for a sonar detection process, some assumption must be made about the nature of the acoustic fluctuation process. Two processes that are widely used in this role are the jump process and the Gauss-Markov process. These processes are similar in that they are both stationer) Markov processes and have autocovariance functions of the form s?²exp(—γt). For these reasons, it might be believed that one could use either of these processes and get comparable results if all one is interested in is computing cumulative detection probabilities or mean time to gain or lose contact. However, such is not the case in that vastly different results can be obtained in some applications. An application of this sort is presented. We also present necessary and sufficient conditions for a threshold to have the property that it is almost surely crossed by the jump process, or by the Gauss-Markov process. This affords another method of comparison.     

Schedule algebra: A progress report

The following paper is the first part of a summary of the schedule algebraic method and its applications to date. It covers the origin and motivation of the schedule algebraic technique, the current status of the algebra as a mathematical system, and a brief outline of the theory of scheduling which the algebra is used to support. Part II of the Progress Report will be published at a later time. It will review applications of the algebra to practical problems and experience gained in the use of the algebra to schedule on-going production systems.     

Offsets as industrial policy: Lessons from aerospace

Since 1975 “offsets” have begun to appear frequently in contracts covering international sales of aircraft and other products incorporating advanced technology. Offsets involve reciprocity beyond that normally found in an exchange of goods for money. They may involve co‐production or co‐design of the principal item to be exchanged, or acceptance by the seller of goods or services unrelated to it as partial payment (indirect offsets or countertrade).

The United States has become the major provider of offsets and anti‐offset sentiment has grown. Economists interpret them as trade diverting. Politicians from regions suffering loss of employment view them as bestowing unfair advantage to foreign competitors.

The authors examine offsets from both theoretical and policy perspectives and conclude that in such noncompetitive markets, second‐best considerations dominate, requiring case‐by‐case evaluation of impacts and rendering across‐the‐board determinations of welfare loss suspect.     

Book review

The politics and economics of defence industries: E. Inbar and B. Zilberfarb (eds), Frank Cass Publishers, London and Portland, Oregon, 1998, pp. xviii+225.

Russia and the Arms Trade: Ian Anthony (ed.), Oxford University Press, SIPRI, 1998, pp. xiv+304.     

Geography and Strategic Stability

This article suggests that the inclusion of geographic considerations helps to create a more nuanced idea of strategic stability. At one level, there are the geographical conditions such as disputing territorial claims that lead policy-makers to perceive the increased propensities for inter-state conflict in a given region. At the other level, there are geostrategic conditions that lead strategic planners to perceive geostrategic vulnerabilities as a result of their assessments about the viability or imminence of military operations.     

The French navy and the Algerian war

The French Navy's part in the Algerian War has been overlooked, but was vitally important. It took two main forms. The first, and primary, mission was to cut off the Algerian nationalists from outside support by a rigorous coastal blockade. Maritime surveillance in the Mediterranean and along the Algerian littoral achieved this. Inshore patrol vessels, supported by larger warships, sealed the routes by which the nationalists sought to infiltrate weapons and newly-trained guerrilla fighters from camps and arms dumps in Tunisia and Morocco. The French Navy intercepted cargo ships that sailed from East Bloc ports, attempting to smuggle arms into the Algerian nationalists. The most celebrated successes were the seizures of the Athos, Slovenija and Lidice in 1958–59. The Navy's second mission involved the deployment ashore, from April 1956, of the marine infantry (the demibrigade of Fusiliers-Marins). These units participated in the sweeps by French army units and engaged insurgent bands. They also garrisoned and protected installations, port facilities and transport networks in Algeria's coastal hinterland.