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A Conceptual Framework for Adapation
No full textThis paper presents a white-box conceptual framework for adaptation that promotes a neat separation of the adaptation logic from the application logic through a clear identification of control data and their role in the adaptation logic. The framework provides an original perspective from which we survey archetypal approaches to (self-)adaptation ranging from programming languages and paradigms, to computational models, to engineering solutions
Statistical Laws Governing Fluctuations in Word Use from Word Birth to Word Death
No full textHow often a given word is used, relative to other words, can convey information about the word’s linguistic utility. Using Google word data for 3 languages over the 209-year period 1800–2008, we found by analyzing word use an anomalous recent change in the birth and death rates of words, which indicates a shift towards increased levels of competition between words as a result of new standardization technology. We demonstrate unexpected analogies between the growth dynamics of word use and the growth dynamics of economic institutions. Our results support the intriguing concept that a language’s lexicon is a generic arena for competition which evolves according to selection laws that are related to social, technological, and political trends. Specifically, the aggregate properties of language show pronounced differences during periods of world conflict, e.g. World War II
Da La Marmora a Ricasoli: l’insediamento del secondo governo Ricasoli e la gestione politica della guerra
No full textBy using new archival materials, my paper Da La Marmora a Ricasoli: l’insediamento del secondo governo Ricasoli e la gestione politica della guerra described the main steps for the appointment of the second cabinet led by Ricasoli and its role in the war of 1866
River Networks and Optimal Channel Networks
No full textRiver networks represent a perfect example of a physical
phenomenon that can be described by means of graph theory.
Water collected by rainfall flows from one point to another
one (downstream) in the river basin creates a spanning (water
flows uniformly on the terrain and therefore from every point
of the basin we have water flow) tree (water cannot flow uphill).
Rivers on Earth and even those that might have been
present on Mars all display similar statistical properties
thereby calling for a model based on basic properties.
A class of models named Optimal Channel Networks (OCN) derive
the final configuration by minimising a given cost function.
The physical inspiration for the minimization problem traces
back to the ideas of Nobel laureate Prigogine on a general
theory of irreversible processes in open dissipative systems.
Actually, theoretical results from OCN allowed to provide an
explanation to universal allometric behaviour in a variety
of different physical situations from species distribution to food webs optimisation alternative to the traditional
approach. In the specific case of river networks, the OCN
model postulates that the total gravitational energy loss in the
system is minimised. Empirical and theoretical works focus
generally on two dimensional case, while recently (inspired by
vascular systems) also the three dimensional case has been
analysed.
Here we devise some new analytical results that illustrate
the role and the properties of the structure that minimises
the cost function proposed in the ABM and we also provide
some insight about the structure of the absolute minimum by varying some of the parameters of the model. In what follows we will give a theoretical characterization of river networks and provide a simple rule to distinguish spanning trees from natural river trees. Furthermore, we extend the study of OCNs embedded on a lattice finding a lower and upper bound for the energy of an OCN in any dimension D
Rastrellamenti e deportazione nell'Italia occupata. Saggio sinottico sulle strutture repressive e sulle dinamiche locali
No full textThe exercise of the violence during the 20. Century knows an exceptional development and differentiation, so that the concept of the violence can be utilized as a category for interpreting the entire history of the century and its relation with the Modernity. The case of the Nazi-Fascist Occupation of Italy can be collocated in this History. A particular place has in this contest the practice of the military operations finalized to the deportation into the concentration and elimination camps. In this essay the Author analysis the functioning of the Nazi-Fascist repression system, examining technically all known military operations (130) that ended with the deportation of political or civil citizens
