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Future directions in the research on unemployment: protean career orientation and perceived employability against social disadvantage
Full text linkFinite volume scheme for the solution of 2D extended Boussinesq equations in the surf zone
No full textIn this paper,a hybrid finite volume-finite difference scheme is applied to study surf zone dynamics.
The numerical model solves the 2DH extended Boussinesq equations proposed by Madsen and Sørensen
(1992) where nonlinear and dispersive effects are both relevant whereas it solves NSWE equations
where nonlinearity prevails. The shock-capturing features of the finite volume method allow an
intrinsic representation of wave breaking and runup; therefore no empirical (calibration) parameters
are necessary. Comparison with laboratory measurements demonstrates that the proposed model can
accurately predict wave height decay and mean water level setup, for both regular and solitary wave
breaking on a sloping beach. The model is also applied to reproduce two-dimensional wave
transformation and breaking over a submerged circular shoal, showing good agreement with
experimental data
Hybrid finite volume – finite difference scheme for 2DH improved Boussinesq equations
No full textIn this paper, a hybrid scheme based on a set of 2DH extended Boussinesq equations for slowly varying
bathymetries is introduced. The numerical code combines the finite volume technique, applied to solve the
advective part of the equations, with the finite difference method, used to discretize dispersive and source
terms. Time integration is performed using the fourth-order Adams–Bashforth–Moulton predictor–corrector
method; the Riemann problem is solved employing an approximate HLL solver, a fourth-order MUSCL-TVD
technique is applied. Five test cases, for non-breaking and breaking waves, are reproduced to verify the
model comparing its results to laboratory data or analytical solutions
Pillole di innovazione. Il Settecento
No full textIl testo affronta con un approccio non convenzionale gli anni della Rivoluzione Industriale avvenuta in Inghilterra, in quanto affronta gli esiti fattuali di quella trasformazione dei processi produttivi, spesso dimenticati nella lettura degli storici. Il testo, pur ricordando gli aspetti tecnici, si concentra sui suoi esiti – cioè i prodotti –, sui suoi attori – quindi le imprese, gli industriali e gli uomini deputati alla promozione commerciale – e sulla sua innovativa dimensione di aggressione dei mercati. Sottolinea anche come l’affermazione del prodotto inglese cambi il profilo della società contemporanea e assecondi le mode del tempo rendendole disponibili, con le opportune diversificazioni, a diverse fasce di mercato, traducendo l’oggetto d’uso in un oggetto di desiderio, trasformando l’uso in consumo ed esportando con esso l’idea della civiltà inglese.The text deals with the years of the Industrial Revolution in England with an unconventional approach, as it addresses the factual results of that transformation of production processes, often forgotten in the reading of historians. The text, while recalling the technical aspects, focuses on its outcomes - that is the products -, on its actors - therefore the companies, the industrialists and the men assigned to commercial promotion - and on its innovative dimension of market aggression. It also underlines how the affirmation of the English product changes the profile of contemporary society and supports the fashions of the time making them available, with the appropriate diversifications, to different market segments, translating the object of use into an object of desire, transforming the use in consumption and exporting with it the idea of English civilization
Numerical simulation of wave overtopping at coastal dikes and low-crested structures by means of a shock-capturing Boussinesq model
No full textIn this paper, a shock-capturing numerical model, based on the combined solution of Boussinesq and nonlinear shallow water equations is applied to the simulation of wave runup, overtopping and wave train propagation over impermeable, emerged and low-crested, structures. In order to improve the performances of the scheme at wet–dry interfaces, a numerical treatment is introduced to provide well-balancing of advective fluxes and source terms. One- and two-dimensional test cases are presented to validate the performances of the model under both regular and irregular wave conditions
Finite Volume – Finite Difference scheme for the solution of 2D extended Boussinesq Equations
No full textThe paper presents a hybrid scheme for the solution of 2DH extended
Boussinesq equations. The finite volume method is applied to the
advective part of the equations, while dispersive and source terms are
discretized by the finite difference technique. To validate the numerical
model, a classical refraction-diffraction test is proposed. Special
attention is devoted to verify the shock-capturing capabilities of the
scheme: the model is applied to one- and two- dimensional runup test
cases with good results, showing that no ad hoc treatment is required at
the shoreline
Shock-capturing Boussinesq model for irregular wave propagation
No full textIn this paper, a shock-capturing numerical model, based on the combined solution of Boussinesq and nonlinear
shallow water equations is validated with respect to the transformation, breaking and runup of irregular
waves. Boussinesq equations are applied where dispersive and nonlinear effects are both relevant,
assuring an appropriate description of wave propagation from intermediate to shallow waters. Nonlinear
shallow water equations are used where dispersion is negligible; their shock-capturing features, exploited
by the application of the finite volume method, enable an intrinsic representation of wave breaking and
swash zone oscillations. No case by case calibration or tracking algorithms are required. Comparisons with
experimental data show that the model is able to simulate wave height variations, mean water level setup,
wave runup, and the generation of nearshore currents accurately
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