Continuous quality production and machine maintenance

This paper formulates a problem of continuous quality production and maintenance of a machine. Quality is assumed to be a known function of the machine's (Markov diffusion process) degradation states. Applications to a specific quality function are used to obtain analytical solutions to an open-loop and feedback stochastic control maintenance problem.     

Quality control and the sales process

Product quality is emerging as a major strategic instrument for competition. The purpose of this article is to assess the effects of quality control on sales, and, vice versa, the effects of the sales process on quality control. A model relating quality control and the sales process (advertising, repeat purchase, and word-of-mouth effects) is developed to evaluate the above relationships. Two special cases, with degenerate and beta distribution for defect items in the production lot, are analyzed in detail. In the former case, analytical results for the optimal quality control schemes are obtained, whereas in the latter, efficient bounds are derived to search for the optimal scheme. It is shown, analytically and numerically, that the sales parameters have significant impact on whether more “stringent” or “tighter” quality control is warranted. Future research directions are also discussed.     

End of the cycle: assessing ETA’s strategies of terrorism

ABSTRACT

In May 2018, the Basque insurgent group Euskadi Ta Askatasuna (ETA) officially disbanded after a 60-year struggle. This inquiry assesses ETA’s violent campaigns using recent conceptual and theoretical advancements from the field of terrorism studies. Three conclusions concerning the group’s strategies of terrorism are advanced. First, ETA regularly targeted civilians to achieve goals other than coercing the Government of Spain; these objectives included outbidding rival separatist groups and spoiling negotiation processes. Second, ETA’s most rapid period of organizational growth occurred as the result of an aggressive terrorist campaign, demonstrating that civilian targeting can serve as a stimulus to rebel group recruitment. Finally, while terrorism did not advance ETA’s primary political objective of creating an independent Basque state, it did enable the group to assume a leading position within the radical Basque separatist movement, helping extend ETA’s lifespan and making the group an embedded actor within the contentious political processes surrounding the question of Basque self-determination. Collectively, these conclusions support recent theoretical findings arguing that non-state terrorism often enables insurgent groups to prolong their lifespans while paradoxically making it more difficult for them to advance their long-term political objectives.     

Guerrillas and bandits in the Serranía de Ronda, 1810–1812

The Spanish Guerrilla (1808–1812) which has given its name to ideologically motivated insurgencies is usually portrayed as a patriotic uprising against the French occupation forces of Napoleon. It was that, in part, but also many other things besides. This case study illustrates its overlap and convergence with banditry but also with social unrest turned into uprisings directed by poor Spaniards against their creditors, as in the storming of Ronda by insurgents in 1810. From the propaganda of the day to the subsequent Spanish patriotic historiography, there has been a tendency to exaggerate the amplitude of events and also the damage that was done to the French forces and the casualty figures inflicted on them.