We analyze the impact of obsolescence of economic inventions by incorporating maintenance costsin the endogenous growth model of expanding product varieties. This contrasts with the existingliterature, which ignores maintenance costs and uses the model of quality improvements todescribe...

Air transport networks have exhibited a trend towards complex dynamics in recent years. Using Lufthansa’s networks as an example, this paper aims to illustrate the relevance of various network indicators - such as connectivity and concentration - for the empirical analysis of airline network...

This paper discusses several strategies for the maintenance of light standards, where each light standard consists of n independent and identical lamps screwed on a chandelier. The lamps are subject to stochastic failures, and must be correctively replaced if the number of failed lamps reaches a...

Asphalt roads are gradually deteriorating over time and need road mending to remain in a good state. Inspections are performed to obtain information about the current state of the road; when the damage achieves the established standards, the road is repaired through a maintenance action that is...