Bioventing is a technology used to abate the presence of pollutants in the subsoil. Microorganisms biodegrade the pollutant but the biochemical reaction requires oxygen and so an airflow is induced in the subsoil by means of injection and/or extraction wells. Costs, final result and decontamination time are reliant on contaminant type, soil permeability and several other factors, but oxygen subsoil concentration plays a very important role. For this reason a rational choice of well locations and flow rates is required. The mathematical definition of the optimal design problem will be set-up starting from a simplified mathematical model describing the bioventing system. A formal definition of decontaminated subsoil will be given and the set of system control variables will be identified. Optimization strategies such as cost minimization and time optimization will be mathematically described.

The effects of a nonminimally coupled curvature-matter model of gravity on planetary orbits are computed. The parameters of the model are then constrained by the observation of Mercury orbit.

In this paper, we propose a viable encoding scheme that, to the best of our knowledge, is the first one to guarantee both perfect secrecy (i.e., no information leakage) and reliable communication over the generalized Ozarow-Wyner's wire-tap channel. To this end, we first introduce a metric called uncertainty rate that, similarly to the equivocation rate metric, captures the amount of information leaked by a coding scheme in the considered threat model, but it is simpler to apply in the context of linear codes. Based on this metric, we provide an alternative and simpler proof of the known result that no linear error correcting code alone can achieve perfect secrecy. Finally, we propose a constructive solution combining secret sharing and linear error-correcting codes, and we show that our solution provides the desired combination of reliable and perfectly secret communication. The provided solution, other than being supported by thorough analysis, is viable in practical communication systems. (C) 2016 Elsevier B.V. All rights reserved. In a typical secure communication system, messages undergo two different encodings: an error-correcting code is applied at the physical layer to ensure correct reception by the addressee (integrity), while at an upper protocol layer cryptography is leveraged to enforce secrecy with respect to eavesdroppers (confidentiality). All constructive solutions proposed so far to concurrently achieve both integrity and confidentiality at the physical layer, aim at meeting the secrecy capacity of the channel, i.e., at maximizing the rate of the code while guaranteeing an asymptotically small information leakage.

We consider a scenario in which certain target locations are monitored through sensors, which are scattered all over a considered area. A quality-of-service threshold imposes that, at any given time, a predefined percentage of the overall number of targets must be monitored. Furthermore, the activated sensors must be able to transmit the sensed information to a central base station, and the different roles assumed by the sensors (sensing, relay or idle) lead to different energy consumptions. We propose an exact algorithm to solve the problem of maximizing the operational time in this scenario, and test it on a set of benchmark instances.

This poster has been presented at the first ILTER Open Science Meeting in Skukuza, Kruger National Park, South Africa, 9-13 October 2016 (https://na.eventscloud.com/ehome/156435), and describes the general purposes and organization of the H2020 project ECOPOTENTIAL (http://www.ecopotential-project.eu/) Questo poster è stato presentato al primo ILTER Open Science Meeting a Skukuza, Kruger National Park, Sud Africa, 9-13 ottobre 2016 (https://na.eventscloud.com/ehome/156435), e descrive gli scopi generali e l'organizzazione del progetto H2020 ECOPOTENTIAL (http://www.ecopotential-project.eu/)

In this work, we consider model problems of piecewise smooth systems inR3, for which we propose minimum variation approaches to find a Filippov sliding vector field on the intersection Σ of two discontinuity surfaces. Our idea is to look at the minimum variation solution in theH1-norm, among either all admissible sets of coefficients for a Filippov vector field, or among all Filippov vector fields. We compare the resulting solutions to other possible Filippov sliding vector fields (including the bilinear and moments solutions). We further show that-in the absence of equilibria-also these other techniques select a minimum variation solution, for an appropriately weightedH1-norm, and we relate this weight to the change of time variable giving orbital equivalence among the different vector fields. Finally, we give details of how to build a minimum variation solution for a general piecewise smooth system inR3.

The first carved ambers appear in the Adriatic area at the end of the eighth century BC with the beginning of the Orientalizing period. Among the most active centers, the Etruscan Verucchio is one of the main poles for the sorting of amber. At the beginning of the sixth century, a fundamental role is exercised from Piceno and the Etruscan Felsina, whose intercept part of the tra!cs previously directed on the Adriatic road. Real amber sculptures of high stylistic level appear towards the second half of the sixth century, found in the rich italic tombs (Basilicata, Apulia, Piceno), traced back to two specialized workshops, localizable in Canosa and Armento, at whose birth they certainly contributed artisans from Ionia and from Etruria.

Adaptive Algebraic Multigrid (or Multilevel) Methods (?AMG)are introduced to improve robustness and efficiency of classical algebraic multigrid methods in dealing with problems where no a-priori knowledge or assumptions on the near null kernel of the underlined Matrix are available. Recently we proposed an adaptive (bootstrap) AMG method, ?AMG, aimed to obtain a composite solver with a desired convergence rate. Each new multigrid component relies on a current (general) smooth vector and exploits pairwise aggregation based on weighted matching in a matrix graph to define a new automatic, general-purpose coarsening process, which we refer to as "the compatible weighted matching". In this work, we present results that broaden the applicability of our method to different finite element discretizations of elliptic PDEs. In particular, we consider systems arising from displacement methods in linear elasticity problems and saddle-point systems that appear in the application of the mixed method to Darcy problems.

The paper concerns a continuous model governed by a ODE system originated by a discrete duopoly model with bounded rationality, based on constant conjectural variation. The aim of the paper is to show (i) the existence of an absorbing set in the phase space; (ii) linear stability analysis of the critical points of the system; (iii) nonlinear, global asymptotic stability of equilibrium of constant conjectural variation.

Hydrogel composite membranes (HCMs) are used as novel mineralization platforms for the bioinspired synthesis of CaCO3 superstructures. A comprehensive statistical analysis of experimental results revealed quantitative relationships between crystallization conditions and crystal texture and the strong selectivity toward complex morphologies when monomers bearing carboxyl and hydroxyl groups are used together in the hydrogel synthesis in HCMs.

PDE models for network flows are used in a number of different applications, including modeling of water channel networks. While the theory and first-order numerics are well developed, there is a lack of high-order schemes. We propose a Runge-Kutta discontinu- ous Galerkin method as an efficient, effective and compact numerical approach for numerical simulations of water flow in open canals. Our numerical tests show the advantages of RKDG over first-order schemes.

The integration of interferometric synthetic aperture radar (InSAR) and GPS tomography techniques for the estimation of the 3-D distribution of atmosphere refractivity is discussed. A methodology to use the maps of the temporal changes of precipitable water vapor (PWV) provided by InSAR as a further constraint in the GPS tomography is described. The aim of the methodology is to increase the accuracy of the GPS tomography reconstruction of the atmosphere's refractivity. The results, which are obtained with SAR and GPS data acquired over the Lisbon area, Portugal, are presented and assessed. It has been found that the reconstruction of the atmospheric refractivity is closer to the real atmospheric state with a mitigation of the smoothing effects due to the usual geometrical constraints of the GPS tomography.

An integro-differential model for evolutionary dynamics with mutations is investigated by improving the understanding of its behaviour using numerical simulations. The proposed numerical approach can handle also density dependent fitness, and gives new insights about the role of mutation in the preservation of cooperation.

We introduce a new class of finite differences schemes to approximate one dimensional dissipative semilinear hyperbolic systems with a BGK structure. Using precise analytical time-decay estimates of the local truncation error, it is possible to design schemes, based on the standard upwind approximation, which are increasingly accurate for large times when approximating small perturbations of constant asymptotic states. Numerical tests show their better performances with respect to those of other schemes.

MONTE SANNACE. Le tombe dipinte dei Peucezi: le indagini su questa collina della provincia di Bari hanno restituito l'esempio meglio conservato di una città della Puglia preromana, ma per capire il livello di civiltà e i rapporti culturali delle genti peucezie che vi si insediarono rivestono particolare importanza le pitture di alcune tombe monumentali appartenute alle élites aristocratiche del luogo.

In this paper, we present an analytical study, in the one space dimensional case, of the fluid dynamics system proposed in [3] to model the formation of biofilms. After showing the hyperbolicity of the system, we show that, in an open neighborhood of the physical parameters, the system is totally dissipative near its unique non-vanishing equilibrium point. Using this property, we are able to prove existence and uniqueness of global smooth solutions to the Cauchy problem on the whole line for small perturbations of this equilibrium point and the solutions are shown to converge exponentially in time at the equilibrium state.

Numerical resolution of two-stream kinetic models in a strong aggregative setting is considered. To illustrate our approach, we consider a one-dimensional kinetic model for chemotaxis in hydrodynamic scaling and the high field limit of the Vlasov-Poisson-Fokker-Planck system. A difficulty is that, in this aggregative setting, weak solutions of the limiting model blow up in finite time, and therefore the scheme should be able to handle Dirac measures. It is overcome thanks to a careful discretization of the macroscopic velocity resulting of Vol'pert calculus: accordingly, a new well-balanced and asymptotic preserving numerical scheme is provided. Numerical simulations confirm a good behavior of solutions.

The study of energetic free-surface flows is challenging because of the large range of interface scales involved due to multiple fragmentations and reconnections of the air-water interface with the formation of drops and bubbles. Because of their complexity the investigation of such phenomena through numerical simulation largely increased during recent years. Actually, in the last decades different numerical models have been developed to study these flows, especially in the context of particle methods. In the latter a single-phase approximation is usually adopted to reduce the computational costs and the model complexity. While it is well known that the role of air largely affects the local flow evolution, it is still not clear whether this single-phase approximation is able to predict global flow features like the evolution of the global mechanical energy dissipation. The present work is dedicated to this topic through the study of a selected problem simulated with both single-phase and two-phase models. It is shown that, interestingly, even though flow evolutions are different, energy evolutions can be similar when including or not the presence of air. This is remarkable since, in the problem considered, with the two-phase model about half of the energy is lost in the air phase while in the one-phase model the energy is mainly dissipated by cavity collapses.

An algorithm for coupling a classical Finite Volume (FV) approach, that discretize the Navier-Stokes equations on a block structured Eulerian grid, with the weakly-compressible SPH is presented. The coupling procedure aims at applying each solver in the region where its intrinsic characteristics can beexploited in the most efficient and accurate way: the FV solver is used to resolve the bulk flow and the wall regions, whereas the SPH solver is implemented in the free surface region to capture details of the front evolution. In order to avoid the difficulties connected with inhomogeneous domain decomposition, in both SPH and FV regions a weakly compressible flow model was firstly tested. However, the coupling procedure has beenimplemented in order to allow the adoption of different time steps between the two solvers. Thanks to this feature, it will be shown that the proposed technique is also able to reproduce an inhomogeneous coupling. Indeed, the FV solver, because of the space discretization adopted and the implicit time integration, naturally tends to an incompressible discrete solver, wherever the time step is much larger of what required to capture compressibility effects. The different coupling strategies as well as convergence studies have been carried out in the 2D framework.The reported results clearly prove that the combined use of the two solvers is convenient from the point of view of both accuracy and computing time.

The starting transient of highly under-expanded supersonic jets is studied by means of very high resolution weighted essentially non oscillatory finite volume schemes, coupled with a positivity-preserving scheme in order to ensure positivity of pressure and density for high compression/expansion ratio. Numerical behaviour of the schemes is investigated in terms of grid resolution, formal accuracy and different approximated Riemann solvers. The transient flow field is also discussed.