Search

We present a study of kinematic asymmetries from the integral field spectroscopic surveys MAGPI and SAMI. By comparing the asymmetries in the ionized gas and stars, we aim to disentangle the physical processes that contribute to kinematic disturbances. We normalize deviations from circular motion by S 05, allowing us to study kinematic asymmetries in the stars and gas, regardless of kinematic temperature. We find a similar distribution of stellar asymmetries in galaxies where we do and do not detect ionized gas, suggesting that whatever is driving the stellar asymmetries does not always lead to gas removal. In both MAGPI and SAMI, we find an anticorrelation between stellar asymmetry and stellar mass, that is absent in the gas asymmetries. After stellar mass and mean-stellar-age matching distributions, we find that at all stellar masses, MAGPI galaxies display larger stellar asymmetry compared to SAMI galaxies. In both MAGPI and SAMI galaxies, we find that star-forming galaxies with old mean-stellar-ages typically have larger asymmetries in their gas compared to their stars, whereas galaxies with young mean-stellar-ages have larger asymmetries in their stars compared to their gas. We suggest that this results from continuous, clumpy accretion of gas. [ABSTRACT FROM AUTHOR]

The paper investigates the advance in the most intimate understanding of the construction methods of the Fabrica Solimene (1952–1955) in Vietri sul Mare, (Campania-Italy). The aim is to increase the level of geometric and informative detail of the model, digitally (re)built by means of an indirect method using a total station survey and subsequently by means of a direct method, i.e., by importing the elaborations derived from laser scanner acquisitions and photographic data sets into a BIM authoring vector software. For this purpose, using photogrammetry, new details are acquired, specifically addressed to the study of the static-mechanical behaviour of the perimeter wall studied in its mathematical configuration of the projecting bodies from bottom to top. This study is organised on the elaboration of new clean and decimated point cloud acquisitions to be converted into volumetric models for direct use in finite element calculation (FEM) codes aimed at structural analysis. Thanks to the proposed procedure, it possible to maintain the level of geometric detail appropriate to the resolution required for the analysis. At the same time, it makes it possible to find the best pipeline to reduce the size of the model and obtain the most accurate static-structural results. [ABSTRACT FROM AUTHOR]

The PERVIVAL project aims at developing an interactive system with the preliminary function of explaining a complex museum collection in a simple and immediate way and allowing the visitor to better understand the museum collection he is about to see. In particular, the interactive system aims at enhancing the understanding of the collections of funeral furnishings of Egyptians, which are characterized by a multiplicity of objects of rich symbolism and connected to each other through complex funeral rituals. The idea is to explain the religious creed of ancient Egyptians through the objects placed in the tomb, having in this way a double benefit: enlightening the rituals and placing the objects back in their primary function. In this way, the knowledge of the visitor is not only enlarged through the description of something that is described on papyruses or inscriptions (hence, not comprehensible) but also the proper function of every single object will be explained through the connection among them, as a function of amulets or goods necessary to travel through the World of the Dead. The connection between the different objects allows a much greater understanding of the exposed collection that would be perceived in this way not as a set of single isolated pieces, but as a harmonious set of complementary elements between they represent a specific historical-cultural context. [ABSTRACT FROM AUTHOR]

Low-cost 3D sensors are nowadays widely diffused and many different solutions are available on the market. Some of these devices were developed for entertaining purposes, but are used also for acquisition and processing of different 3D data with the aim of documentation, research and study. Given the fact that these sensors were not developed for this purpose, it is necessary to evaluate their use in the capturing process. This paper shows a preliminary research comparing the Kinect 1 and 2 by Microsoft, the Structure Sensor by Occipital and the O&P Scan by Rodin4D in a medical scenario (i.e. human body scans). In particular, these sensors were compared to Minolta Vivid 9i, chosen as reference because of its higher accuracy. Different test objects were analysed: a calibrated flat plane, for the evaluation of the systematic distance error for each device, and three different parts of a mannequin, used as samples of human body parts. The results showed that the use of a certified flat plane is a good starting point in characterizing the sensors, but a complete analysis with objects similar to the ones of the real context of application is required. For example, the Kinect 2 presented the best results among the low-cost sensors on the flat plane, while the Structure Sensor was more reliable on the mannequin parts. [ABSTRACT FROM AUTHOR]

Digital modelling archaeological and architectural monuments in their current state and in their presumed past aspect has been recognized not only as a way for explaining to the public the genesis of a historical site, but also as an effective tool for research. The search for historical sources, their proper analysis and interdisciplinary relationship between technological disciplines and the humanities are fundamental for obtaining reliable hypothetical reconstructions. This paper presents an experimental activity defined by the project Cultural Heritage Through Time - CHT2 funded in the framework of the Joint Programming Initiative on Cultural Heritage (JPI-CH) of the European Commission. Its goal is to develop time-varying 3D products, from landscape to architectural scale, deals with the implementation of the methodology on one of the case studies: the late Roman circus of Milan, built in the era when the city was the capital of the Western Roman Empire (286-402 A.D). The work presented here covers one of the cases in which the physical evidences have now been almost entirely disappeared. The diachronic reconstruction is based on a proper mix of quantitative data originated by 3D surveys at present time and historical sources like ancient maps, drawings, archaeological reports, archaeological restrictions decrees and old photographs. Such heterogeneous sources have been first georeferenced and then properly integrated according to the methodology defined in the framework of the CHT2 project, to hypothesize a reliable reconstruction of the area in different historical periods. [ABSTRACT FROM AUTHOR]

Cultural Heritage documentation and preservation has become a fundamental concern in this historical period. 3D modelling offers a perfect aid to record ancient buildings and artefacts and can be used as a valid starting point for restoration, conservation and structural analysis, which can be performed by using Finite Element Methods (FEA). The models derived from reality-based techniques, made up of the exterior surfaces of the objects captured at high resolution, are-for this reason-made of millions of polygons. Such meshes are not directly usable in structural analysis packages and need to be properly pre-processed in order to be transformed in volumetric meshes suitable for FEA. In addition, dealing with ancient objects, a proper segmentation of 3D volumetric models is needed to analyse the behaviour of the structure with the most suitable level of detail for the different sections of the structure under analysis. Segmentation of 3D models is still an open issue, especially when dealing with ancient, complicated and geometrically complex objects that imply the presence of anomalies and gaps, due to environmental agents such as earthquakes, pollution, wind and rain, or human factors. The aims of this paper is to critically analyse some of the different methodologies and algorithms available to segment a 3D point cloud or a mesh, identifying difficulties and problems by showing examples on different structures. [ABSTRACT FROM AUTHOR]

Although 3D models are useful to preserve the information about historical artefacts, the potential of these digital contents are not fully accomplished until they are not used to interactively communicate their significance to non-specialists. Starting from this consideration, a new way to provide museum visitors with more information was investigated. The research is aimed at valorising and making more accessible the Egyptian funeral objects exhibited in the Sforza Castle in Milan. The results of the research will be used for the renewal of the current exhibition, at the Archaeological Museum in Milan, by making it more attractive. A 3D virtual interactive scenario regarding the "path of the dead", an important ritual in ancient Egypt, was realized to augment the experience and the comprehension of the public through interactivity. Four important artefacts were considered for this scope: two ushabty, a wooden sarcophagus and a heart scarab. The scenario was realized by integrating low-cost Virtual Reality technologies, as the Oculus Rift DK2 and the Leap Motion controller, and implementing a specific software by using Unity. The 3D models were implemented by adding responsive points of interest in relation to important symbols or features of the artefact. This allows highlighting single parts of the artefact in order to better identify the hieroglyphs and provide their translation. The paper describes the process for optimizing the 3D models, the implementation of the interactive scenario and the results of some test that have been carried out in the lab. [ABSTRACT FROM AUTHOR]

Regional healthcare performance evaluation systems can help optimize healthcare resources on regional basis and improve the performance of healthcare services provided. The Tuscany region in Italy is a good example of an institution which meets these requirements. China has yet to build such a system based on international experience. In this paper, based on comparative studies between Tuscany and China, we propose that the managing institutions in China's experimental cities can select and commission a third-party agency to, respectively, evaluate the performance of their affiliated hospitals and community health service centers. Following some features of the Tuscan experience, the Chinese municipal healthcare performance evaluation system can be built by focusing on the selection of an appropriate performance evaluation agency, the design of an adequate performance evaluation mechanism and the formulation of a complete set of laws, rules and regulations. When a performance evaluation system at city level is formed, the provincial government can extend the successful experience to other cities. [ABSTRACT FROM AUTHOR]

The expansion in vacuum of the plume generated by the UV ablation of a LiYF4 crystal was analysed as a function of several parameters: distance from the target along the plume axis, laser fluency and angular dislocation with respect to the plume axis. The study was carried out by the optical time of flight technique. Time-resolved signals of the optical emission of the neutral as well as ionised species in the plume were recorded and analysed for different experimental situations. The most probable velocity for each species was calculated and confirmed by the Maxwell-Boltzmann distribution fits of the relative emission temporal profiles. An angular distribution of the ablated species could also be provided. [ABSTRACT FROM AUTHOR]

Abstract: The realization of crystalline films of Nd 3+ :YF3 and Nd 3+ :LiYF4 on a monocrystalline LiYF4 substrate by pulsed laser deposition is reported. The films were obtained by laser ablation with 355 nm photons of a bulk LiYF4 crystal doped with Nd 3+ ions at 1.5% atomic concentration in the presence of different ablation/deposition parameters. The films optical characteristics, analyzed via laser induced polarized fluorescence spectroscopy upon IR excitation, are presented. Lifetime measurements of the fundamental Nd3+ ion transition in the film were also performed. All these results were compared with those obtained in the Nd 3+ :LiYF4 bulk crystal. The surface morphology of the depositions was analyzed via a scanning electron microscope. When the production of the deposition took place in high vacuum (1×10−4 Pa) and the substrate temperature was 750 °C, the grown film was Nd 3+ :YF3. A 1 Pa controlled atmosphere of He in the ablation chamber and a substrate temperature of 650 °C favoured the growth of a Nd 3+ :LiYF4 film. In the latter case the film showed also a smoother surface. [Copyright &y& Elsevier]

Abstract: The realization of a monocrystalline nanofilm of Nd3+-doped fluoride on LiYF4 substrates by pulsed laser deposition is reported. The film was obtained by laser ablation with 355 nm photons of a bulk LiYF4 crystal doped with Nd3+ ions at 1.5% atomic concentration. The measurements of the sample thickness obtained by an in situ interferometric technique, and the film optical characteristics analyzed via laser induced fluorescence spectroscopy upon UV and IR excitation, are presented. Lifetime measurements of the fundamental Nd3+ ion transition in the film were also performed. All the results were compared with those obtained in a Nd3+:LiYF4 bulk crystal. The emission spectra of the deposited film following IR excitation seem to indicate the obtained deposit is Nd3+:YF3. [Copyright &y& Elsevier]

Abstract: We show how the interaction between Ga atoms and silica samples in a hot environment gives rise to permanent inclusions of Ga inside the silica matrix which, in turn, produce typical luminescence features. The Ga doped silica is analyzed via laser induced fluorescence, photoluminescence and electron paramagnetic resonance spectroscopies. The results evidence the presence of modifications induced by the Ga inclusions inside the silica matrix and some preliminary hypothesis on their nature are advanced. Possible applications of such Ga doped silica are also mentioned. [Copyright &y& Elsevier]

Abstract: We performed temporal as well as frequency-resolved emission spectroscopy of the plasma plume generated in vacuum by 355nm pulsed laser ablation of a LiYF4:Tm3+ crystal (1% Tm3+ concentration) and a LiYF4:Nd3+ crystal (1.5% Nd3+ concentration). The plume emission spectrum is very rich in features and shows the elemental lines belonging to all the components of the host lattice, either neutral or ionized. The time-resolved analysis of some emission features is discussed and some stream velocities are derived. A possible model for the time evolution of the plume components is reported. The electronic detection technique was used to detect the onset of the plasma plume and to measure the ablation laser fluence threshold. [Copyright &y& Elsevier]

This paper reports on the excitation of the nP→52S1/2 series, when Ga vapour inside a quartz cell, with or without buffer gas, at a temperature larger than 900°C, is resonantly excited by laser pulses at 403.3 nm corresponding to the 42P1/2→52S1/2 excitation. The analyses of the fluorescence intensities as a function of several different experimental parameters demonstrate the nP levels to be populated via energy-pooling ionisation. [Copyright &y& Elsevier]