Purity of Blood and the Curial Market in Iberian Cathedrals

This article analyses the dynamics of accessing cathedral chapters with purity of blood statutes in the Iberian Peninsula, from a comparative perspective, and the interaction with the phenomenon of commodification of ecclesiastical benefices. This phenomenon created a Curial market that was open to any applicant with sufficient economic capacity, regardless of their ancestry. What was the result of the clash between the Iberian concept of purity and the commodified Roman reality?

Scheduling the repair of aircraft components - a case study

In aircraft components maintenance shops, components are distributed amongst repair groups and their respective technicians based on the type of repair, on the technicians skills and workload, and on the customer required dates. This distribution planning is typically done in an empirical manner based on the group leader’s past experience. Such a procedure does not provide any performance guarantees, leading frequently to undesirable delays on the delivery of the aircraft components. Among others, a fundamental challenge faced by the group leaders is to decide how to distribute the components that arrive without customer required dates. This paper addresses the problems of prioritizing the randomly arriving of aircraft components (with or without pre-assigned customer required dates) and of optimally distributing them amongst the technicians of the repair groups. We proposed a formula for prioritizing the list of repairs, pointing out the importance of selecting good estimators for the interarrival times between repair requests, the turn-around-times and the man hours for repair. In addition, a model for the assignment and scheduling problem is designed and a preliminary algorithm along with a numerical illustration is presented.