Search results for " Photonics"
showing 10 items of 510 documents
FOR A CONSCIUOS FRUITION OF THE CULTURAL HERITAGE OF ANCIENT NOTO (SICILY). EFIAN PROJECT AS OPPORTUNITY FOR VALORISATION
2017
Abstract. The archaeological site of Ancient Noto is all that remains of one of the most interesting and important cities in the Est part of Sicily. Architecture and political life made Noto a point of reference for the island, expecially in XVI and XVII century, before it was destroyed by a devastating earthquake in 1963. A general project of safeguard, together with archaeological excavations, could hand a great amount of information, archaeological finds, pieces of architecture, that are useful to understand the site, known as a "Sicilian Pompei". Our intervention has the aim to describe the importance of EFIAN (Experimental Fruition Ingenious Ancient Noto). The project is carried out as…
Employing Microwave Graphene Field Effect Transistors for Infrared Radiation Detection
2018
In this work, we investigate the possibility of employing graphene field effect transistors, specifically designed for microwave applications, as infrared detectors for telecom applications. Our devices have been fabricated on a sapphire substrate employing CVD-grown transferred graphene. The roles of both the gate dielectric and the DC bias conditions have been evaluated in order to maximize the infrared generated signal through an experimental investigation of the signal-to-noise ratio dependence on the transistor operating point.
3D RECONSTRUCTION OF THE ROMAN DOMUS IN THE ARCHAEOLOGICAL SITE OF LYLIBAEUM (MARSALA, ITALY)
2019
Abstract. Generally, terrestrial laser scanning surveys involve a rather large number of scans to ensure a high percentage of overlap required for the scan registration phase (target-based or point-based registration, cloud-to-cloud registration). These approaches result in data redundancy that could slow down both the acquisition and post-processing phases. In recent years, the technological evolution in the field of laser scanners has been directed to the development of devices that are able to perform an onsite pre-registration, to optimize the survey procedures and the reliability of the registration of the scan. The paper presents the results achieved during a terrestrial laser scannin…
THE INTEGRATED 3D SURVEY for UNDERGROUND ARCHAEOLOGICAL ENVIRONMENT
2019
Abstract. The task of documentation and conservation of Cultural Heritage defines the challenges that geomatics techniques have to overtake in order to provide different solutions that combine the automation of processes with accurate results. The employment of integrated technologies allows improving the documentation of Cultural Heritage from a quantitative and qualitative point of view. The use of range and image-based techniques ensures the possibility to completely record articulated structures such as building with underground environments. The latter present often problematic survey conditions that imposed well planned and appropriate solutions. In this context, the paper presents th…
DIGITAL PHOTOGRAMMETRY, TLS SURVEY and 3D MODELLING for VR and AR APPLICATIONS in CH
2020
Abstract. The world of valorization of Cultural Heritage is even more focused on the virtual representation and reconstructions of digital 3D models of monuments and archaeological sites. In this scenario the quality and the performances offered by the virtual reality (VR) and augmented reality (AR) navigation take primary importance, improving the accessibility of cultural sites where the real access is not allowed for natural conditions or human possibilities. The creation of a virtual environment useful for these purposes requires a specific workflow to follow, combining different strategies in the fields of survey, 3D modelling and virtual navigation. In this work a specific case of stu…
Supercontinuum Generation and Intermodal Four-Wave Mixing in a Step-Index Few-Mode Fibre
2019
International audience; The complex spatiotemporal dynamics of nonlinear light propagation in multimode fibers (MMFs) has recently witnessed a renewed interest because of their experimental realization in emerging key areas of laser physics and fiber optics [1]. Specifically, MMFs have a number of linear and nonlinear optical properties that make them very attractive to investigate new spatiotemporal effects fundamentally different from standard single-mode fibers. These include the observation of multimode solitons [2], intermodal four-wave mixing (FWM) [3], geometric parametric instabilities [4], spatial beam self-cleaning [5], and the generation of supercontinuum (SC) light when pumping …
ARAB-NORMAN HERITAGE: STATE OF KNOWLEDGE AND NEW ACTIONS AND INNOVATIVE PROPOSAL
2017
Abstract. This paper wants to offers a perlustrative recognition on the 'state of the studies', concerning to the Arab-Norman architecture of Palermo, admissed by Unesco in 2015 and explain a research in progress which, starting from re-cognition of the peculiarities of the restoration work carried out on it, consisting of the identification of authentic material-constructive values and / or reconstruction, it orients itself to develop a concrete proposal of filing for a more conscious knowledge. She, moreover, wants contribute to real enhancement through the use of targeted communication strategies that use innovative means capable, on one hand, to attracting the greatest possible number o…
INTEGRATED SURVEYNG WITH MOBILE MAPPING SYSTEM, EGNOS, NTRK AND LASER TECHNOLOGIES IN THE PARK "NINNI CASSARA" IN PALERMO
2018
Abstract. This article summarizes the experience gained between 2012 and 2013 by the department of "Civil Engineering, Environmental, Aerospace and Materials" of University of Palermo on the integrated survey of Ninni Park Cassara Park in Palermo and the subsequent testing of methods, tools and techniques based on current research regarding the acquisition and processing of GNSS (Global Navigation Satellite System) data and laser-scanner. A fruitful time dedicated to the design of the survey has allowed us to become aware of the critical issues that the site presents because of its vast extent and diversity in size and number of the elements of which it is composed. The work has been addres…
Autonomous hyperspectral UAS photogrammetry for environmental monitoring applications
2014
Abstract. The unmanned airborne system (UAS) remote sensing using lightweight multi- and hyperspectral imaging sensors offer new possibilities for the environmental monitoring applications. Based on the accurate measurements of the way in which the object reflect and emit energy, wide range of affecting variables can be monitored. Condition for reliable applications is reliable and accurate input data. In many applications, installation of geometric and radiometric reference targets in the object area is challenging, for instance, in forest or water areas. On the other hand, UASs are often operated in very poor conditions, under clouds or under variable cloud cover. Our objective is to deve…
Tree species recognition in species rich area using UAV-borne hyperspectral imagery and stereo-photogrammetric point cloud
2017
Abstract. Recognition of tree species and geospatial information of tree species composition is essential for forest management. In this study we test tree species recognition using hyperspectral imagery from VNIR and SWIR camera sensors in combination with 3D photogrammetric canopy surface model based on RGB camera stereo-imagery. An arboretum forest with a high number of tree species was used as a test area. The imagery was acquired from the test area using UAV-borne cameras. Hyperspectral imagery was calibrated for providing a radiometrically corrected reflectance mosaic, which was tested along with the original uncalibrated imagery. Alternative estimators were tested for predicting tree…