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Le Prince de Fra Paolo. Romain Borgna, ed. Libre pensée et littérature clandestine 67. Paris: Honoré Champion, 2017. 220 pp. €45.
No full textBody condition in fish as a tool to detect the effects of anthropogenic pressures in transitional waters
No full textIn the last years, increasing interest has been dedicated to the quality assessment of brackish-water systems. Traditionally, fish community is an important biological element used to assess the quality status of transitional water bodies. In this study, we analysed the effect of anthropogenic pressures on the population of a small teleost, the sand smelt Atherina boyeri, in a Mediterranean lagoon by means of body condition. Fish were sampled once a year during the period 2010–2012, in 32 sampling sites, and for each specimen individual body condition factor was estimated. A negative significant correlation was found between condition factor and pressures related to alteration of the hydrographic regime, while a significant positive correlation was found with trophic status indicators and fishery activities. Therefore, morphological and hydrological alteration of coastal lagoons, modifying the quality and the availability of resources, seems to influence the health of resident populations
Intervento nel dibattito Italia senza sinfonia
No full textL'articolo è parte di un'inchieste sulle ragione che hanno impedito alll'Italia di ottenere un posto tra le nazioni impegnati nella musica strumentale, e in particolare della sinfonia
Gathering of robots in a ring with mobile faults
No full textThis paper studies the well-known problem of gathering multiple mobile agents moving in a graph, but unlike previous results, we consider the problem in the presence of an adversarial mobile entity which we call the malicious agent. The malicious entity can occupy any empty node and prevent honest mobile agents from entering this node. This new adversarial model is interesting as it models transient mobile faults that can appear anywhere in a network. Moreover, our model lies between the less powerful delay-fault model, where the adversary can block an agent for only a finite time, and the more powerful but static fault model of black holes that can even destroy the agents. We study the problem for ring networks and we provide a complete characterization of the solvability of gathering, depending on the size n of the ring and the number of agents k. We consider both oriented or unoriented rings with either synchronous or asynchronous agents. We prove that in an unoriented ring network with asynchronous agents the problem is not solvable when k is even, while for synchronous agents the problem is unsolvable when both n is odd and k is even. We then present algorithms that solve gathering for all the remaining cases, thus completely solving the problem. Finally, we provide a proof-of-concept implementation of the synchronous algorithms using programmable Lego Mindstorms EV3 robots
Gesti emotivi e gesti verbali. L’eredità di George Herbert Mead sulla genesi del linguaggio umano
No full textIn the first decade of the past century, G.H. Mead formulated the idea that proper verbal communication among humans developed from exchanges of emotional gestures. The paper reconstructs Mead’s position, by pointing out that it involved a deep revision of Wundt's traditional conception of communication as consisting in the outer expression of emotions understood as preexisting mental states. On the contrary, Mead adopted an idea of emotions as basic tools for the mutual regulation of social behaviors. On the other hand, he developed an idea of language largely rooted in affective and embodied resources, consequently reinforcing the continuity between sensibility and language. Furthermore, the paper points out that Mead radically distanced himself from a mentalistic approach to the genesis of language and sociality, by adopting the idea that individual minds arise out of conversations of verbal gestures.
By referring to the current debate in the philosophy of mind, philosophy of language and evolutionary psychology, the author traces the development of certain theoretical issues involved in Mead’s approach, such as the idea of a retroaction of human linguistic practices on animal sensibility as well as the thesis of a mutual configuration of the highly social human form of life and our embodied and linguistically shaped ecological niche
Network-decentralised optimisation and control: an explicit saturated solution
No full textThis paper proposes a decentralised explicit (closed-form) iterative formula that solves convex programming problems with linear equality constraints and interval bounds on the decision variables.
In particular, we consider a team of decision agents, each setting the value of a subset of the variables, and a team of information agents, in charge of ensuring that the equality constraints are fulfilled. The structure of the constraint matrix imposes a communication pattern between decision and information agents, which can be represented by a bipartite graph.
We associate each information agent with an integral variable and each decision agent with a saturated function, which takes the interval bounds into account, and we design a decentralised dynamic mechanism that globally converges to the optimal solution.
Under mild conditions, the convergence is shown to be exponential.
We also provide a discrete-time algorithm, based on the Euler system, and we give an upper bound for the step parameter to ensure convergence.
Although the considered optimisation problem is static, the proposed scheme can be successfully applied
to find the optimal solution of network-decentralised dynamic control problems
An insight into the mechanical properties of selected commercial oil and alkyd paint films containing cobalt blue
No full textPigments and binders are known to influence drying and ageing mechanisms of paint films. However, the study of the long-term mechanical behaviour of paint films and its relationship with paint degradation and conservation still needs further investigation. This paper presents an insight into the role of cobalt blue pigment in the mechanical properties of some modern paint films by studying selected commercial oil and alkyd paint films containing cobalt blue. In addition, several representative mock-ups containing cobalt blue mixed with drying and semi-drying oils and some common additives were also tested for comparison purposes. Optical microscopy, SEM-EDX, XRF, VIS-reflectance spectroscopy, FTIR-ATR and GC-MS analysis were carried out to identify pigments, binders, additives and fillers. Uniaxial tensile measurements were run to test the mechanical performance of the studied paint films. The differences in the mechanical behaviour led to the evaluation of the discrepancies found in the chemical and physical properties of the different formulations studied