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Simulazione CAD di operazioni di montaggio
No full textSUMMARY The engine assembly department of Piaggio & C. S.p.A. in the industrialization phase of the new engine M648, propose the introduction of a new method for the analysis of assembly phases and for the studies of the necessary machines and equipments.
This need arose because the design of equipments, machinery and the same assembly line was entrusted to outside suppliers.
We have, therefore, issues related to the expectations of the buyer, confidentiality of information that they provided with the order and any delays which can occur for misunderstandings between the parties.
The purpose of this work is to improve the assembly cycle, generating a 3D image for each phase of work, by using the modelling software CAD.
Thus, focusing on clarity of documentations to be sent during application equipment, is expected to reduce drastically the time of supplies.
RIASSUNTO: Il processo di montaggio di un motore è molto articolato: analizzando tutte le operazioni con particolare attenzione alle macchine, alle attrezzature necessarie e ai tempi; l’obiettivo è di generare un’immagine 3D per ogni fase di lavoro, per maggiore chiarezza, da cui ci si aspetta una riduzione dei tempi
Le Manuel d’économie politique de Jeremy Bentham au prisme de la traduction d’Etienne Dumont et des relectures de James Mill et de John Stuart Mill
No full textThis article aims to contribute to the reconstruction of Bentham's economic texts, examining the story of the "Manuel d’économie politique" through its various editions. This article is divided into two parts: the first part studies the history of the editing activity on the "Manuel" that Étienne Dumont performed between 1798 and 1811. The second part examines the changes introduced in the third edition of 1826, which derive from the cooperation between Dumont and two prominent British economists: James and John Stuart Mill
QCD Phase Transition in a Strong Magnetic Background
No full textWe investigate the properties of the deconfining/chiral restoring transition
for two flavor QCD in presence of a uniform background magnetic field. We adopt
a standard staggered discretization of the fermion action and a lattice spacing
of the order of 0.3 fm. We explore different values of the bare quark mass,
corresponding to pion masses in the range 200 - 480 MeV, and magnetic fields up
to |e|B ~ 0.75 GeV^2. The deconfinement and chiral symmetry restoration
temperatures remain compatible with each other and rise very slightly (< 2 %
for our largest magnetic field) as a function of the magnetic field. On the
other hand, the transition seems to become sharper as the magnetic field
increases
A New Approach To The Treatment Of Separatrix Chaos And Its Applications
No full textSUMMARY We consider time-periodically perturbed 1D Hamiltonian systems possessing one
or more separatrices. If the perturbation is weak, then the separatrix chaos is
most developed when the perturbation frequency lies in the logarithmically
small or moderate ranges: this corresponds to the involvement of resonance
dynamics into the separatrix chaos. We develop a method matching the discrete
chaotic dynamics of the separatrix map and the continuous regular dynamics of
the resonance Hamiltonian. The method has allowed us to solve the long-standing
problem of an accurate description of the maximum of the separatrix chaotic
layer width as a function of the perturbation frequency. It has also allowed us
to predict and describe new phenomena including, in particular: (i) a drastic
facilitation of the onset of global chaos between neighbouring separatrices,
and (ii) a huge increase in the size of the low-dimensional stochastic web
Lactose as an inexpensive starting material for the preparation of aldohexos-5-uloses: synthesis of L-ribo and D-lyxo derivatives
No full textSUMMARY: Partially protected derivatives of L-ribo- and D-lyxo-aldohexos-5-ulose have been prepared starting from triacetonlactose dimethyl acetal derivatives. Key steps of the synthetic sequences are a) the synthesis of 4'-deoxy-4'-eno- and 6'-deoxy-5'-eno lactose derivatives, and b) the epoxidation-methanolysis of the above enol ethers to give 1,5-bis-glycopyranosides, masked form of the target 1,5-dicarbonyl hexoses
Secure token passing at application level
No full textSUMMARY We introduce an application level implementation of a token passing operation. After an introduction that explains the conceptual principles, we describe exhaustively the state machines that implement our solution. The security requirements are carefully considered, since the token is a sensitive resource, but without introducing scalability limit
RFID microchip internal implants: effects on grapevine histology
No full textSUMMARY Interesting applications for traceability in agriculture have recently been developed using radiofrequency identification (RFID) technology. A preliminary report of survival and growth in grapevine suggested pith not only as optimal microchip localization within the plant, but only continuous monitoring of performances, supported by histological observation of tissues around microchips, can validate this approach as a long-term strategy for grapevine identification. In this study, histological assays of grapevine plants are reported, considering different strategies in RFID marking. Microchip insertion after direct drilling of pith from a distal cut on rootstocks did not show any differences in tissue status compared to control, and this can be adequately correlated to an absence of effect in plant growth. Conversely, a “U” cut performed laterally on the rootstock to insert the microchip, which involved tissues from bark to pith, caused development of callus tissues, restoring transversal continuity, but with a partial loss of functionality in terms of open vessels. This phenomenon can be considered permanent damage to plant vascular function, but with limited extension
La casa de Jorge Isaacs en Ibagué - Colombia. El proyecto de conocimiento.
Get PDFRIASSUNTO Il presente articolo descrive l’esperienza accademica svolta nel Programma di Architettura dell’Università di Ibagué (Colombia) all’interno dell’accordo con l’Università di Pisa (Italia) mediante il corso di specializzazione estivo che si è svolto dal 30 luglio all’11 agosto del 2007 con il proposito di realizzare uno studio preliminare sul progetto di conoscenza e restauro della casa di Jorge Isaacs localizzata ad Ibagué. Jorge Isaacas nasce a Cali (Colombia) nel 1837 ed è stato uno dei più grandi scrittori colombiani, autore dell’opera letteraria “Maria”, la più famosa novella romantica del secolo XIX ed ha abitato negli ultimi anni della sua vita nella città di Ibagué dove è morto nel 1895 proprio in questa casa oggetto di studio. Questo lavoro risponde agli interessi dell’Università di Ibagué di riscattare, anche mediante una missione istituzionale, l’identità culturale del luogo e della Casa di Jorge Isaacs, edificio considerato uno dei più interessanti della città per il suo valore storico ed architettonico, motivo per il quale è inserito nell’Inventario dei Beni Culturali del Ministero della Cultura di Colombia. SUMMARY This article presents the academic experience related to the architecture programme between the University of Ibaguè (Colombia) and the University of Pisa (Italy). The aim of the summer course, carried out from 30th July to 11th August of 2007, is the realization of a preliminary study on the knowledge and restoration project of Jorge Isaacas’house located in Ibaguè. Jorge Isaacas was born in Calì (Colombia) in 1837. He has been one of the best Colombian writers, author of the opera “Maria”, the most famous romantic novel of XIX century. He spent the end of his life in Ibaguè where he died in 1985 in the house object of study. This work aims to give evidence of the University of Ibaguè interests to redeem, even with institutional procedures, the cultural identity of the Jorge Isaacas’house. This building is considered one of the most interesting in the city for his historical and architectonic value. In fact the building is included in the list of cultural goods of the Culture Ministry of Colombia
A few notes on the Borda and Condorcet methods
No full textThe present Technical Report contains a short analysis of both the Borda and the Condorcet methods. We start with a description of both methods in their twofold roles: of methods for defining a winning alternative from a set of available alternatives,} of possible outranking methods over a set of alternatives. We then discuss the properties of each method and analyze them with regard to the conditions posed by the Arrow's impossibility theorem. The last step, that represents the core part of the Technical Report, is represented by the search of possible relations between the two methods. The Technical Report closes with the proposal of a composed outranking method based on both the Borda and the Condorcet methods executed on the same profiles of preferences. As usual, reports of errors and inaccuracies are gratefully appreciated
Compact DSOP Forms Derived from SOP Expressions
No full textWe give a new heuristic for Disjoint Sum-of-Products (DSOP) minimization of a Boolean function , based on a new criterion for product selection. Starting from a Sum-of-Products (SOP) of , i.e., a set of cubes covering the minterms of , we assign a weight to each product (cube) in , where depends on the intersection of with the other cubes of . We assign higher weights to the cubes that, if selected in a DSOP, would generate a higher fragmentation of the other cubes. Disjoint cubes are then selected for increasing value of and decreasing size, recomputing the SOP on the residual function at different possible stages as a trade-off between quality of result and computational time. We also propose a heuristic for computing partial DSOP forms, i.e., SOP forms whose cubes cover exactly once a given subset of minterms of the function, and more than once the remaining minterms.A set of experiments conducted on major benchmark functions show that our method, with all its variants, always generates better results than the ones of previous heuristics, including the one based on a BDD representation of . These experiments have also outlined how re-synthesizing the residual function in SOP form seems to be crucial for obtaining compact DSOPs