An oil pipeline design problem

Copyright @ 2003 INFORMSWe consider a given set of offshore platforms and onshore wells producing known (or estimated) amounts of oil to be connected to a port. Connections may take place directly between platforms, well sites, and the port, or may go through connection points at given locations. The configuration of the network and sizes of pipes used must be chosen to minimize construction costs. This problem is expressed as a mixed-integer program, and solved both heuristically by Tabu Search and Variable Neighborhood Search methods and exactly by a branch-and-bound method. Two new types of valid inequalities are introduced. Tests are made with data from the South Gabon oil field and randomly generated problems.The work of the first author was supported by NSERC grant #OGP205041. The work of the second author was supported by FCAR (Fonds pour la Formation des Chercheurs et l’Aide à la Recherche) grant #95-ER-1048, and NSERC grant #GP0105574

Cheese trademarks: Italian dairy firms’ practices during the 20th century

Trademarks have recently become a very useful sources for business historians. This longitudinal analysis of the twentieth-century trademarking activities of the most important Italian dairy firms of the era, namely Galbani, Invernizzi and Locatelli, demonstrates that trademarks were used both as a protective weapon against competitors and as an innovation carrier to open up new markets. This article also argues that trademark registrations had another dual purpose – not only were they used as buffers against negative shocks but they were also used to support periods of economic growth. A fundamental finding of this work is that trademarks, across various types of registrations, were closely connected to the features on which the companies based their sales strategies

Nuovo Piano regolatore generale del Comune di Cerignola

Pubblicato in: red., Il Politecnico “firma” il Prg di Cerignola, in “Il Sole 24 Ore”, 4 dicembre 1999; Aa. Vv., Periferie e nuove urbanità, a cura di F. Bucci, Electa, Milano 2003. Esposto in occasione delle mostre: La vera città, ricerche e progetti, Museo Nazionale della Scienza e della Tecnica, Milano, 3-19 dicembre 1999; Periferie e nuove urbanità, Triennale di Milano, giugno-ottobre 2003; Festival dell’Architettura 5 2009-2010, Parma, Reggio Emilia Modena, 26 novembre-12 dicembre 2010

Four Shorts Stories on Surprising Algorithmic Uses of Treewidth

This article briefly describes four algorithmic problems where the notion of treewidth is very useful. Even though the problems themselves have nothing to do with treewidth, it turns out that combining known results on treewidth allows us to easily describe very clean and high-level algorithms.Comment: 17 page