The baroque marble altars in some church of Bari (Italy): 3d survey, characterization and prevenance of materials and valorization hypothesis

This paper focuses on the polychrome marble altars of the crypt of the St. Sabino’s Cathedral and of the St. Giacomo church, both in Bari (Italy), precious evidences of use and reuse of ancient marble, combined with local materials. The study is part of a larger research project (MARMORA), related to ancient marbles used in the Cultural Heritage of Puglia, and aims to improve knowledge and preserve these works, in order to improve their valorization and enjoyment. Therefore, firstly a high definition investigation was performed, then the characterization and provenance studies of the stone materials were carried out. Preliminary results allowed to obtain a virtual and digital representation of the altars, including the whole dataset on the characterization of the materials and suggested valorization and conservation hypothesis

Integrating cross-border acquisitions: a process-oriented approach

Acquisizioni o fusioni spesso falliscono nel creare valore per gli azionisti poiché, nella maggior parte dei casi, le modalità di integrazione impediscono di sviluppare le opportune sinergie. Questo argomento è stato affrontato da molti studi secondo due differenti filoni di pensiero: il primo guarda alla combinazione di risorse a disposizione dopo l’acquisizione e il secondo si focalizza sul fattore umano. Lo studio propone un modello integrato, dove gli effetti di questi aspetti sono testati simultaneamente e considera tre variabili indipendenti: l’importanza della pianificazione del processo, la conoscenza derivante da acquisizioni precedenti e la conoscenza derivante da relazioni precedenti. Crediamo che attraverso questo modello i manager possano prioritizzare le loro azioni e selezionare un orizzonte temporale appropriato per l’integrazione.Acquisitions and mergers of equals often fail to deliver shareholder value, largely because poor integration practices do not allow synergies to be created. The issue has been addressed by several studies from two different research streams: the first looks at the combination of resources after the acquisitions and the second focuses on the human factor. We propose an integrated model where the effects of these key aspects are tested simultaneously and where three independent variables are included: the extent of planning and knowledge from previous acquisitions and knowledge from previous relationships. We believe that through the model managers can prioritise their actions and select an appropriate time horizon for the integratio

A Machine Learning-Based Approach for Audio Signals Classification using Chebychev Moments and Mel-Coefficients

This paper proposes a machine learning-based architecture for audio signals classification based on a joint exploitation of the Chebychev moments and the Mel-Frequency Cepstrum Coefficients. The procedure starts with the computation of the Mel-spectrogram of the recorded audio signals; then, Chebychev moments are obtained projecting the Cadence Frequency Diagram derived from the Mel-spectrogram into the base of Chebychev moments. These moments are then concatenated with the Mel-Frequency Cepstrum Coefficients to form the final feature vector. By doing so, the architecture exploits the peculiarities of the discrete Chebychev moments such as their symmetry characteristics. The effectiveness of the procedure is assessed on two challenging datasets, UrbanSound8K and ESC-50

First Principles Analysis of Electron-Phonon Interaction in Graphene

The electron-phonon interaction in monolayer graphene is investigated by using density functional perturbation theory. The results indicate that the electron-phonon interaction strength is of comparable magnitude for all four in-plane phonon branches and must be considered simultaneously. Moreover, the calculated scattering rates suggest an acoustic phonon contribution that is much weaker than previously thought, revealing the role of optical phonons even at low energies. Accordingly it is predicted, in good agreement with a recent measurement, that the intrinsic mobility of graphene may be more than an order of magnitude larger than the high values reported in suspended samples.Comment: 12 pages, 4 figure

Combined Use of Terrestrial Laser Scanning and IR Thermography Applied to a Historical Building

Abstract: The conservation of architectural heritage usually requires a multidisciplinary approach involving a variety of specialist expertise and techniques. Nevertheless, destructive techniques should be avoided, wherever possible, in order to preserve the integrity of the historical buildings, therefore the development of non-destructive and non-contact techniques is extremely important. In this framework, a methodology for combining the terrestrial laser scanning and the infrared thermal images is proposed, in order to obtain a reconnaissance of the conservation state of a historical building. The proposed case study is represented by St. Augustine Monumental Compound, located in the historical centre of the town of Cosenza (Calabria, South Italy). Adopting the proposed methodology, the paper illustrates the main results obtained for the building test overlaying and comparing the collected data with both techniques, in order to outline the capabilities both to detect the anomalies and to improve the knowledge on health state of the masonry building. The 3D model, also, allows to provide a reference model, laying the groundwork for implementation of a monitoring multisensor system based on the use of non-destructive techniques

Macroscopic polarization and band offsets at nitride heterojunctions

Ab initio electronic structure studies of prototypical polar interfaces of wurtzite III-V nitrides show that large uniform electric fields exist in epitaxial nitride overlayers, due to the discontinuity across the interface of the macroscopic polarization of the constituent materials. Polarization fields forbid a standard evaluation of band offsets and formation energies: using new techniques, we find a large forward-backward asymmetry of the offset (0.2 eV for AlN/GaN (0001), 0.85 eV for GaN/AlN (0001)), and tiny interface formation energies.Comment: RevTeX 4 pages, 2 figure

Mt. Etna Volcanic Aerosol and Ash Retrievals using MERIS and AATSR Data

Envisat MERIS and AATSR data have been acquired in the framework of the Eurorisk-Preview project. The project addresses European civil protections and proposes to develop, at the European scale, new information services to support the risk management. In Italy one of the most important natural risks is due to the presence of volcanoes. Mt. Etna in Sicily, displays persistent activity, periodically interrupted by eruptions, which emit volcanic aerosol and ash to different altitudes in troposphere affecting the central Mediterranean area. In order to test the use of MERIS and AATSR data to derive emitted particles parameters as optical depth, effective radius and the ash mass of particles, the already developed remote sensing techniques has been adapted. MERIS and AATSR data acquired during the Mt. Etna 2002-2003 volcanic eruption has been chosen. The use of VIS and TIR bands of the two sensor demonstrates the potential to derive useful information on plume particles and to monitor the volcanic plume during eruption if frequent and high resolution data is available in near real time

Ultrathin films of black phosphorus as suitable platforms for unambiguous observation of the orbital Hall effect

Phosphorene, a monolayer of black phosphorus, is a two-dimensional material that lacks a multivalley structure in the Brillouin zone and has negligible spin-orbit coupling. This makes it a promising candidate for investigating the orbital Hall effect independently of the valley or spin Hall effects. To model phosphorene, we utilized a DFT-derived tight-binding Hamiltonian, which is constructed with the pseudo atomic orbital projection method. For that purpose, we use the PAOFLOW code with a newly implemented internal basis that provides a fairly good description of the phosphorene conduction bands. By employing linear response theory, we show that phosphorene exhibits a sizable orbital Hall effect with strong anisotropy in the orbital Hall conductivity for the out-of-plane orbital angular momentum component. The magnitude and sign of the conductivity depend upon the in-plane direction of the applied electric field. These distinctive features enable the observation of the orbital Hall effect in this material unambiguously. The effects of strain and of a perpendicularly applied electric field on the phosphorene orbital-Hall response are also explored. We show that a supplementary electric field applied perpendicular to the phosphorene layer in its conductive regime gives rise to an induced in-plane orbital magnetization.Comment: 8 pages, 4 figure

Micro- and Nanoscale Measurement Methods for Phase Change Heat Transfer on Planar and Structured Surfaces

In this opinion piece, we discuss recent advances in experimental methods for characterizing phase change heat transfer. We begin with a survey of techniques for high-resolution measurements of temperature and heat flux at the solid surface and in the working fluid. Next, we focus on diagnostic tools for boiling heat transfer and describe techniques for visualizing the temperature and velocity fields, as well as measurements at the single bubble level. Finally, we discuss techniques to probe the kinetics of vapor formation within a few molecular layers of the interface. We conclude with our outlook for future progress in experimental methods for phase change heat transfer.United States. Dept. of Energy (Advanced Research Projects Agency-Energy Grant DE-AR0000363)National Science Foundation (U.S.) (Grant 1261824)United States. Office of Naval Research (Grant N00014-13-1-0324