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The unconventional inclusion of monolithic vertical type structures as well as traditional rubble mounds in shallow water yacht harbours can pose interesting challenges for both design and construction of breakwaters and quay walls. This paper describes the design, construction and post-construction aspects of two recent microtidal projects in western Italy, located at the mouth of the river Arno (Boccadarno at Marina di Pisa) and of the drainage channel Rio Martino (Latina, near Rome). The vertical structures made at the shallow roundheads with either reinforced concrete caissons or a crown of micropiles improve the stability, the navigational safety and the wave attenuation in the harbour basins, as compared to traditional rubble mounds, despite the more complex singularity. The vulnerable transitions (due to complex localized hydrodynamics) need specific three-dimensional model testing and preliminary oversizing of the sloping armour. [ABSTRACT FROM AUTHOR]

The MoSE barriers system was designed and constructed at the inlets of the Venice Lagoon (Italy) in order to limit and tame the flooding events in the Lagoon areas and in the City. The success of the design and operation of the system has been demonstrated by the significant reduction in the number and intensity of floods in the lagoon since its beginning of operations in 2020. In this study, we investigate the dynamical behavior of the MoSE system at full-scale by analyzing the barriers behavior during the severe storm event of November 22nd, 2022. In particular, the dynamical response of the Chioggia barrier to waves and storm surge is studied in detail. Spectral analysis of field records, barrier and inlet modal analyses and Empirical Orthogonal Functions (EOF) techniques are applied to provide a key for interpreting the actual behavior of such a complex system during a storm event, highlighting dominant frequencies and checking for the occurrence of resonance phenomena. First, a brief review of the experimental and theoretical studies carried out over the past forty years is given. Modal patterns of gates oscillations detected via EOF analysis confirm the presence of the eigenmodes of both the barrier and the inlet; however, the gates oscillations during the considered event are mild and the hydraulic performances of the system are satisfactory for the severe event studied. Further field measurements and future severe events should be studied to reach extended conclusions. • Field records of the MOSE gates' motions analyzed during a severe event (RP=30 yrs) • Spectral, modal, EOF methods estimate gates and free surface oscillations' frequencies • Some gates and inlet modal oscillations detected but with limited mode amplifications • Barrier long period oscillations driven by longitudinal and cross modes of the inlet [ABSTRACT FROM AUTHOR]

Transient waves generated by a box falling into water are analytically and experimentally investigated (Scott Russell wave generator). Within the frame of linear theory, a new analytical solution for the leading wave is proposed. It is shown that both the impulse pressure of the box's impact on the free surface and the velocity field generated during the underwater phase (wave generator type boundary condition) have to be taken into account when predicting wave amplitude and period. The analytical solution, in satisfactory agreement with experiments performed in a two-dimensional flume, can be used for validating numerical models and for estimating the order of magnitude of landslide-generated waves. DOI: 10.1061/(ASCE)0733-950X(2008)134:1(53) CE Database subject headings: Water waves; Transient flow; Landslides; Tsunamis.

The complex dynamics of the Venice tidal barrier subjected to broadbanded wave spectra are investigated by applying empirical orthogonal function (EOF) analysis to experimental data sets. Space and frequency patterns of the natural modes of the barrier are reconstructed and satisfactorily compared with the recent theory of Li and Mei. The results indicate that when broadbanded wave spectra are considered, natural modes with the longest spatial wavelengths seem more likely to be excited than those with shorter wavelengths. CE Database subject headings: Italy; Barriers; Tides; Tidal effects; Gates.

This paper looks at the iterative techniques and the convergence criteria that are necessary to deal with two difficulties in the integration of the full elliptic mild-slope equation, by means of an FEM model. The first difficulty is the nonlinearity due to the inclusion of a wave breaking dissipation factor. This paper gives an overall description of an iterative technique and presents an effective convergence criterion. It shows that this technique, although fully reliable, is time-consuming. Therefore the present paper also sets out to present an accelerated method, which is shown to be up to five times faster than the standard one. The second difficulty arises from the generally adopted boundary reflection condition, which depends on the angle--not known a priori--between the incident wave direction and the normal vector to the reflective boundary. A suitable iterative method and an efficient convergence criterion are presented here, along with validation tests aimed at simulating total absorption. Both nonlinear wave breaking and total absorption are important for coastal-morphology applications. A test on a domain reproducing a sloping beach has therefore been carried out in order to investigate the behavior of both these iterative techniques when used simultaneously.

Pharmacokinetics induced by drug eluting stents (DES) in coronary walls is modeled by means of a one-dimensional multi-layered model, accounting for vessel curvature and non-homogeneous properties of the arterial tissues. The model includes diffusion mechanisms, advection effects related to plasma filtration through the walls, and bio-chemical drug reactions. A non-classical Sturm-Liouville problem with discontinuous coefficients is derived, whose closed-form analytical solution is obtained via an eigenfunction expansion. Soundness and consistency of the proposed approach are shown by numerical computations based on possible clinical treatments involving both hydrophilic and hydrophobic drugs. The influence of the main model parameters on drug delivery mechanisms is analyzed, highlighting the effects induced by vessel curvature and yielding comparative indications and useful insights into the concurring mechanisms governing the pharmacokinetics., (Copyright © 2015. Published by Elsevier Inc.)