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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.

Examines the techniques and convergence criteria needed to deal with difficulties in the integration of the full elliptic mild-slope equation, by means of a finite element method (FEM) model. Overview of the gemma FEM model; Discussion on nonlinear wave breaking; Validation tests and results.

Perforated multichamber caisson breakwaters are widely used for deep water harbour protection from waves, causing a partial dissipation of wave energy, hence reducing wave reflection. The innovative patented geometry presented in this paper, the ARPEC, is an Anti Reflection PErmeable Caisson breakwater that allows a significant wave energy dissipation and a hydraulic connection between the sea side and the port side by means of a labyrinthine pattern of offset openings in all external and internal walls. The hydraulic response of this innovative structure is evaluated by means of both 2D physical and numerical models. It is shown that, when compared with traditional impermeable perforated caissons, the marginal increase of wave transmission ( C T = H T / H I in the approximate range of 0.1–0.2, varying with wave period) is compensated by a slight reduction of wave reflection ( C R = H R / H I in the approximate range of 0.3–0.6, varying with wave period) and by an enhanced water circulation in the sheltered basin, which is beneficial for flushing of microtidal harbours. • Novel geometry concept of perforated caisson, ARPEC, Anti Reflection PErmeable Caisson. • 2D Physical model tests on hydraulic performance of the ARPEC with length scale 35.55 in Froude Similarities. • 2D numerical model tests with OpenFOAM Software. The accordance between the numerical and physical models is evaluated by means of cross validation with the determination coefficient R2 that varies from 0.87 (for incident wave height) to 1 (for wave period) as evidence of a very good accordance between the numerical and physical models. • Reflection (C R) and transmission (C T) coefficients analysis has been performed under regular and random wave action, obtaining, for random waves C R values in the range 0.28–0.58 and C T between 0.13 and 0.22. • Water flushing analysis by imposing initial sea-level gradient between the sea and port sides of the caisson. [ABSTRACT FROM AUTHOR]

This paper illustrates a methodology to get a reliable estimation of the local wave properties, based on the reconstruction of the motion of a moving sailboat by means of GNSS receivers installed on board and an original kinematic positioning approach. The wave parameters reconstruction may be used for many useful practical purposes, e.g., to improve of autopilots, for real-time control systems of ships, to analyze and improve the performance of race sailboats, and to estimate the local properties of the waves. A Class 40 oceanic vessel (ECO40) left from the port of "Riva di Traiano" located close to Rome (Italy) on 19 October 2014 to perform a non-stop sailing alone around the world in energy and food self-sufficiency. The proposed system was installed on ECO40 and the proposed method was applied to estimate the wave properties during a storm in the Western Mediterranean Sea. The results compared against two sets of hindcast data and wave buoy records demonstrated the reliability of the method. [ABSTRACT FROM AUTHOR]

Presents a commentary on the treatment of wave breaking and total absorption in a mild-slope equation finite-element method model. Use of a parabolic version of the model; Convergence parameters as function of iteration number; Importance of element size in modeling.

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.)