Proceedings of the International Conference (Gioia del Colle, October 21-22, 2014)

Il presente volume è compreso in una serie di attività scientifiche conclusive che rientrano in una delle principali e fondamentali azioni previste dal progetto T.He.T.A (Technological tools for the promotion of the Transadriatic Archaeological Heritage), finanziato nell' ambito dell' European Territorial Cooperation Programme Greece-Italy 2007-2013, del quale il CNR-IAC è il Leader Partner. La scelta di un tema talmente affascinante, quale il lusso delle aristocrazie peucezie, nasce dalla volontà di approfondire questo importante aspetto delle genti indigene che hanno occupato la Puglia centrale per quasi un millennio, indagando alcuni fenomeni sociologici e culturali legati alle manifestazioni del lusso e della ricchezza. Per questo motivo, sono stati spesso presi in considerazione alcuni tra i contesti più significativi provenienti dai centri più importanti dell' area, cercando di metterne in risalto gli elementi e gli atteggiamenti comuni nell' uso e nel possesso dei beni di lusso e di prestigio, con particolare riguardo ai manufatti greci, e i rapporti con l' opposta sponda adriatica e con le isole greche dello Ionio (Corfù tra tutte). Infine, nell' analisi della documentazione funeraria, una particolare attenzione è stata prestata alle informazioni inerenti l' identità sociale dei proprietari delle tombe e ai diversi rituali funerari di cui questi individui sono stati oggetto.

This paper deals with the derivation of a collective model of cell populations out of an individual-based description of the underlying physical particle system. By looking at the spatial distribution of cells in terms of time-evolving measures, rather than at individual cell paths, we obtain an ensemble representation stemming from the phenomenological behavior of the single component cells. In particular, as a key advantage of our approach, the scale of representation of the system, i.e., microscopic/discrete vs. macroscopic/continuous, can be chosen a posteriori according only to the spatial structure given to the aforesaid measures. The paper focuses in particular on the use of different scales based on the specific functions performed by cells. A two-population hybrid system is considered, where cells with a specialized/differentiated phenotype are treated as a discrete population of point masses while unspecialized/undifferentiated cell aggregates are represented by a continuous approximation. Numerical simulations and analytical investigations emphasize the role of some biologically relevant parameters in determining the specific evolution of such a hybrid cell system.

This paper presents a new approach to the modeling of vehicular traffic flows on road networks based on kinetic equations. While in the literature the problem has been extensively studied by means of macroscopic hydrodynamic models, to date there are still not, to the authors' knowledge, contributions tackling it from a genuine statistical mechanics point of view. Probably one of the reasons is the higher technical complexity of kinetic traffic models, further increased in case of several interconnected roads. Here such difficulties of the theory are overcome by taking advantage of a discrete structure of the space of microscopic states of the vehicles, which is also significant in view of including the intrinsic microscopic granularity of the system in the mesoscopic representation.

We show in this paper that the roots $x_1$ and $x_2$ of a scalar quadratic polynomial $ax^2 + bx + c = 0$ with real or complex coefficients $a, b, c$ can be computed in an element-wise mixed stable manner, measured in a relative sense. We also show that this is a stronger property than norm-wise backward stability but weaker than element-wise backward stability. We finally show that there does not exist any method that can compute the roots in an element-wise backward stable sense, which is also illustrated by some numerical experiments.

The equality constrained indefinite least squares problem involves the minimization of an indefinite quadratic form subject to a linear equality constraint. In this paper, we study this problem and present a numerical method that is proved to be backward stable in a strict sense, i.e., that the computed solution satisfies a slightly perturbed equality constrained indefinite least squares problem. We also perform a sensitivity analysis of this problem and derive bounds for the accuracy of the computed solution. We give several numerical experiments to illustrate these results.

Well-balanced schemes were introduced to numerically enforce consistency with longtime behavior of the underlying continuous PDE. When applied to linear kinetic models, like the Goldstein-Taylor system, this construction generates discretizations which are inconsistent with the hydrodynamic stiff limit (despite it captures diffusive limits quite well). A numerical hybridization, taking advantage of both time-splitting (TS) and well-balanced (WB) approaches is proposed in order to fix this defect: numerical results show that resulting composite schemes improve rendering of macroscopic fluxes while keeping a correct hydrodynamic stiff limit.

The work deals the monitoring of a single ancient landslide detected in the Vonace area, southwards of Maierato (Calabria, Italy). A 18-hour-measurement campaign has been carried out using the Ground-based Synthetic Aperture Radar (GBSAR) interferometry technique carried between March, 25th and 26th. Displacement maps have been geolocated and overlaid to a Digital Elevation Model of the scene. It has been observed that the Vonace area is almost stable except two portions located at the foot of the ancient landslide and at the centre of the town, respectively. In both cases, a maximum displacement of about 0.5 mm has been measured. A further campaign is needed to confirm this displacement.

The modeling of various physical questions often leads to nonlinear boundary value problems involving a nonlocal operator, which depends on the unknown function in the entire domain, rather than at a single point. In order to answer an open question posed by J.R. Cannon and D.J. Galiffa, we study the numerical solution of a special class of nonlocal nonlinear boundary value problems, which involve the integral of the unknown solution over the integration domain. Starting from Cannon and Galiffa's results, we provide other sufficient conditions for the unique solvability and a more general convergence theorem. Moreover, we suggest different iterative procedures to handle the nonlocal nonlinearity of the discrete problem and show their performances by some numerical tests.

We prove global existence and uniqueness of smooth solutions to a nonlinear system of parabolic-elliptic equations, which describes the chemical aggression of a permeable material, like calcium carbonate rocks, in presence of acid atmosphere. This model applies when convective flows are not negligible, due to the high permeability of the material. The global (in time) result is proven by using a weak continuation principle for the local solutions.

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In this paper we review the dry port concept and its outfalls in terms of optimal design and management of freight distribution. Some optimization challenges arising from the presence of dry ports in intermodal freight transport systems are presented and discussed. Then we consider the tactical planning problem of defining the optimal routes and schedules for the fleet of vehicles providing transportation services between the terminals of a dry-port-based intermodal system. An original service network design model based on a mixed integer programming mathematical formulation is proposed to solve the considered problem. An experimental framework built upon realistic instances inspired by regional cases is described and the computational results of the model are presented and discussed.

In this paper we propose a classification of crowd models in built environments based on the assumed pedestrian ability to foresee the movements of other walkers. At the same time, we introduce a new family of macroscopic models, which make it possible to tune the degree of predictiveness of the individuals. By means of these models we describe both the natural behavior of pedestrians, i.e., their expected behavior according to their real limited predictive ability, and a target behavior, i.e., a particularly efficient behavior one would like them to assume (for, e.g., logistic or safety reasons). Then we tackle a challenging shape optimization problem, which consists in controlling the environment in such a way that the natural behavior is as close as possible to the target one, thereby inducing pedestrians to behave more rationally than what they would naturally do. We present numerical tests which elucidate the role of rational/predictive abilities and show some promising results about the shape optimization problem.

The motion of a test particle in the gravitational field of a non-spherical source endowed with both mass and mass quadrupole moment is investigated when a test radiation field is also present. The background is described by the Erez-Rosen solution, which is a static spacetime belonging to the Weyl class of solutions to the vacuum Einstein's field equations, and reduces to the familiar Schwarzschild solution when the quadrupole parameter vanishes. The radiation flux has a fixed but arbitrary (non-zero) angular momentum. The interaction with the radiation field is assumed to be Thomson-like, i.e., the particles absorb and re-emit radiation, thus suffering for a friction-like drag force. Such an additional force is responsible for the PoyntingRobertson effect, which is well established in the framework of Newtonian gravity and has been recently extended to the general theory of relativity. The balance between gravitational attraction, centrifugal force and radiation drag leads to the occurrence of equilibrium circular orbits which are attractors for the surrounding matter for every fixed value of the interaction strength. The presence of the quadrupolar structure of the source introduces a further degree of freedom: there exists a whole family of equilibrium orbits parametrized by the quadrupole parameter, generalizing previous works. This scenario is expected to play a role in the context of accretion matter around compact objects.

Motivated by the picture of a thin accretion disc around a black hole, radiating mainly in the direction perpendicular to its plane, we study the motion of test particles interacting with a test geodesic radiation flux propagating perpendicular to the equatorial plane in a Schwarzschild space-time. We assume that the interaction (kind of Poynting-Robertson effect) is modelled by an effective term corresponding to a Thomson-type radiation drag. After approximating the individual photon trajectories in quite an accurate way, we solve the continuity equation (up to linear order in M) in order to find a consistent radiation-flux density, prescribing a certain plausible equatorial profile. The combined effect of gravitation and radiation is illustrated on several figures; they confirm that the particles are generically strongly influenced by the flux, in particular, they are both collimated and accelerated in the direction perpendicular to the disc, but the acceleration received in this manner is not enough to explain highly relativistic outflows emanating from some black-hole-disc sources. Main improvement needed is a more realistic description of the radiation-particle interaction, allowing for Compton-type frequency-dependent effect and particle heating/cooling.

In a recent paper we proposed a numerical method to solve a non-standard non-linear second order integro-differential boundary value problem. Here, we answer two questions remained open: we state the order of convergence of this method and provide some sufficient conditions for the uniqueness of the solution both of the discrete and the continuous problem. Finally, we compare the performances of the method for different choices of the iteration procedure to solve the non-standard nonlinearity.

tProtected areas are experiencing increased levels of human pressure. To enable appropriate conserva-tion action, it is critical to map and monitor changes in the type and extent of land cover/use and habitatclasses, which can be related to human pressures over time. Satellite Earth observation (EO) data andtechniques offer the opportunity to detect such changes. Yet association with field information and expertinterpretation by ecologists is required to interpret, qualify and link these changes to human pressure.There is thus an urgent need to harmonize the technical background of experts in the field of EO dataanalysis with the terminology of ecologists, protected area management authorities and policy makers inorder to provide meaningful, context-specific value-added EO products. This paper builds on the DPSIRframework, providing a terminology to relate the concepts of state, pressures, and drivers with the appli-cation of EO analysis. The type of pressure can be inferred through the detection of changes in state (i.e.changes in land cover and/or habitat type and/or condition). Four broad categories of changes in stateare identified, i.e. land cover/habitat conversion, land cover/habitat modification, habitat fragmentationand changes in landscape connectivity, and changes in plant community structure. These categories ofchange in state can be mapped through EO analyses, with the goal of using expert judgement to relatechanges in state to causal direct anthropogenic pressures. Drawing on expert knowledge, a set of pro-tected areas located in diverse socio-ecological contexts and subject to a variety of pressures are analysedto (a) link the four categories of changes in state of land cover/habitats to the drivers (anthropogenic pres-sure), as relevant to specific target land cover and habitat classes; (b) identify (for pressure mapping) themost appropriate spatial and temporal EO data sources as well as interpretations from ecologists andfield data useful in connection with EO data analysis. We provide detailed examples for two protectedareas, demonstrating the use of EO data for detection of land cover/habitat change, coupled with expertinterpretation to relate such change to specific anthropogenic pressures. We conclude with a discussionof the limitations and feasibility of using EO data and techniques to identify anthropogenic pressures,suggesting additional research efforts required in this direction