Search results for "cienza"

Graphene as a tunable resistor

2014

We present the design of a graphene-based electronically tuneable microstrip attenuator operating at a frequency of 5 GHz. The use of graphene as a variable resistor is discussed and the modelling of its electromagnetic properties at microwave frequencies is fully addressed. The design of the graphene-based attenuator is described. The structure integrates a patch of graphene, whose characteristics can range from being a fairly good conductor to a highly lossy material, depending on the applied voltage. By applying the proper voltage through two high-impedance bias lines, the surface resistivity of graphene can be modified, thereby changing the insertion loss of the microstrip attenuator.

Educazione autentica, coscienze prepedagogica, pedagogia spontanea nel progetto metodico di una "pedagogia fondamentale"

2012

L’approccio di una pedagogia metodicamente strutturata permette di indagare in profondità i fenomeni educativi, poiché ne coglie la realtà oggettiva che rivela aspetti importanti del modo di essere nel mondo proprio dell’educando e dell’educatore, e che prospetta il loro autentico poter essere. L’educazione intesa come esperienza vissuta nella relazione interpersonale è infatti una realtà complessa, che per essere compresa adeguatamente richiede approcci disciplinari, logiche e linguaggi diversi. L’orizzonte di senso in cui la questione “pedagogica” dell’educazione autentica si presenta è l’esperienza quotidiana dell’educatore e dell’educando. La coscienza non edotta dal sapere pedagogico ―…

Freedom and Redistribution

2012

In this paper we study the determinants of peopleís attitudes toward income inequality and their economic consequences. We argue that an individualís atti- tudes toward inequality depend upon the extent of freedom of choice and control over life outcomes he enjoys. We construct a two-stage empirical model where people Örst choose the level of income transfers and then their optimal level of ef- fort. We Önd that the higher the extent of an individualís free choice and control over life outcomes, the greater the probability that he supports larger income di§erences as incentives for individual e§ort. We also show that this relationship determines important consequences for the individualís w…

Stochastic differential calculus for wind-exposed structures with autoregressive continuous (ARC) filters

2008

In this paper, an alternative method to represent Gaussian stationary processes describing wind velocity fluctuations is introduced. The technique may be considered the extension to a time continuous description of the well-known discrete-time autoregressive model to generate Gaussian processes. Digital simulation of Gaussian random processes with assigned auto-correlation function is provided by means of a stochastic differential equation with time delayed terms forced by Gaussian white noise. Solution of the differential equation is a specific sample of the target Gaussian wind process, and in this paper it describes a digitally obtained record of the wind turbolence. The representation o…

“Disobbedienza civile «conservativa» e neocostituzionalismo: rilevanza e limiti di un dibattito teorico”.

2004

Il saggio intende presentare una ricostruzione della rilevanza del tema della disobbedienza civile nelle dottrine c.d. neocostituzionaliste del diritto, con particolare riferimento alla dottrina di Ronald Dworkin. Il saggio, dopo avere distinto la pratica della disobbedienza civile da altre pratiche di resistenza, mostra la rilevanza della tematica della disobbedienza civile per il pensiero di Dworkin e segnala tre punti deboli della sua argomentazione. In primo luogo la difficile distinzione tra argomenti basati su politiche e argomenti basati su diritti. In secondo luogo si evidenzia il contrasto tra la accettazione da parte dell'autore dell'idea che in casi di disobbedienza civile il giu…

Processing and characterization of highly oriented fibres of biodegradable nanocomposites

2015

Abstract Biodegradable polymeric materials are becoming day by day ever more important in packaging, agriculture, single-use cutleries and other large consumer applications. The major part of those materials is used under the form of film, i.e. subjected to elongational flow, but the main problem is that they often offer poor mechanical properties. Adding nanofillers, like Multi Walled Carbon Nanotubes (MWCNTs) may solve this problem but only if there is a full control of their orientation inside the material. Aim of this work is to investigate the processing-properties-morphology relationships for a system prepared under elongation flow of MaterBi and commercial MWCNTs. The materials were …

SHAKEDOWN ANALYSIS BY BEM

2000

In the ambit of the symmetric Galerkin boundary element formulation the statical shakedown load multiplier and the limit analysis are reformulated making use of macrozone modelling. The subdivision of the domain into macroelements makes it possible to deal with piecewise homogeneous materials of the body. For each macroelement a discretization of the boundary and a subdivision of the domain into portions called cells are performed in order to introduce the unknowns (i.e. traction and displacement discontinuities) on the boundary and material plastic laws appropriately interpolated. The weighed regularity imposed between adjacent macroelements produces algebraic operators which are symmetric…

FORMULAZIONE SIMMETRICA DEL BEM NELL' ANALISI ELASTICA DI SISTEMI LASTRE- PIASTRE

2011

Glass/basalt hybrid sandwiches for nautical applications

2011

Glass-basalt/epoxy hybrid composites for marine applications

2011

Abstract The aim of this work is to evaluate the influence of uniaxial basalt fabric layers on the mechanical performances of a glass mat/epoxy composite used for marine applications. Polymer composites, reinforced by glass mat (GFRP), and hybrid ones, reinforced by glass mat and unidirectional basalt fabric, have been produced by vacuum bagging technique. Three points bending and tensile tests have been carried out in order to evaluate the effect of number and position of basalt layers on the mechanical properties of the investigated structures. The experimental tests have showed that the presence of two external layers of basalt involves the highest increase in mechanical properties of hy…