Search results for "VISION"
showing 10 items of 5066 documents
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…
Spectral imaging from UAVs under varying illumination conditions
2013
Abstract. Rapidly developing unmanned aerial vehicles (UAV) have provided the remote sensing community with a new rapidly deployable tool for small area monitoring. The progress of small payload UAVs has introduced greater demand for light weight aerial payloads. For applications requiring aerial images, a simple consumer camera provides acceptable data. For applications requiring more detailed spectral information about the surface, a new Fabry-Perot interferometer based spectral imaging technology has been developed. This new technology produces tens of successive images of the scene at different wavelength bands in very short time. These images can be assembled in spectral data cubes wit…
SNAPSHOT SPECTRAL AND COLOR IMAGING USING A REGULAR DIGITAL CAMERA WITH A MONOCHROMATIC IMAGE SENSOR
2017
Spectral imaging (SI) refers to the acquisition of the three-dimensional (3D) spectral cube of spatial and spectral data of a source object at a limited number of wavelengths in a given wavelength range. Snapshot spectral imaging (SSI) refers to the instantaneous acquisition (in a single shot) of the spectral cube, a process suitable for fast changing objects. Known SSI devices exhibit large total track length (TTL), weight and production costs and relatively low optical throughput. We present a simple SSI camera based on a regular digital camera with (i) an added diffusing and dispersing phase-only static optical element at the entrance pupil (diffuser) and (ii) tailored compressed sensing…
A2Ba: Adaptive Background Modelling for Visual Aerial Surveillance Conditions
2015
International audience; Background modelling algorithms are widely used to define a part of an image that most time remains stationary in a video. In surveillance tasks, this model helps to recognize those outlier objects in an area under monitoring. Set up a background model on mobile platforms (UAVs, intelligent cars, etc.) is a challenging task due camera motion when images are acquired. In this paper, we propose A2Ba, a robust method to support instabilities caused by aerial images fusing different information about image motion. We used frame difference as first approximation, then age of pixels is estimated. This latter gives us an invariability level of a pixel over time. Gradient di…
VALUTAZIONI METRICHE DI PIATTAFORME APR PER RILIEVI E MODELLAZIONI 3D
2015
L’articolo descrive le esperienze condotte per la valutazione metrica di blocchi aerei acquisiti con differenti sistemi APR utilizzati nell’ambito del rilievo di BB.CC.. Il lavoro è stato svolto su due siti che differiscono per estensione e caratteristiche morfologiche utilizzando due diverse piattaforme APR, un sistema multi-rotore e un sistema ad ala fissa.
Experimental Analysis of Velocity Distribution in a Coarse-Grained Debris Flow: A Modified Bagnold’s Equation
2020
Today, Bagnold&rsquo
Verification of IRRILAB Software Application for the Hydraulic Design of a Micro-Irrigation System by Using IRRIPRO for an Apple Farm in Sicily
2021
In recent years, many studies have been performed to develop simple and accurate methods to design micro-irrigation systems. However, most of these studies are based on numerical solutions that require a high number of iterations and attempts, without ensuring to maximize water use efficiency and energy-saving. Recently, the IRRILAB software, which is based on an analytical approach to optimally design rectangular micro-irrigation units, has been developed, providing the solution corresponding to the maximum energy-saving condition, for any slope of the laterals and of the manifold. One IRRILAB limitation is that, according to its theoretical basis, the rectangular planform geometry and uni…
La historia entre verdades 'discutibles' y mercado de las noticias
2015
En un contexto cultural en el que los temas históricos se han convertido en una simple mercancía, Italia es además un interesante ejemplo de uso político de la Historia con una ambiciosa finalidad estratégica de dimensión europea: volver a definir la legitimidad de las grandes transformaciones de la edad contemporánea, especialmente, las que van desde la Revolución francesa, a la Revolución de Octubre, hasta el movimiento de Resistencia antifascista. En este sentido, la obra del historiador Renzo de Felice sigue siendo objeto de debate y punto de partida de una constante discusión ideológica. In a cultural context in which historical matters have become a simple merchandise, Italy is also …
La Resistenza, entre memoria y revisionismo
2015
La Resistenza es sin duda un momento clave de la historia italiana del siglo XX. Pero, a pesar de haber sido narrada en muchas obras tanto literarias como en ensayos, aún hay detalles e historias que quizás no sean conocidas por el público no especializado. Además, sobre todo en los últimos años, ha habido cada vez un mayor número de obras de periodistas o historiadores que han dado del movimiento una visión bastante alejada de la tradicionalmente dominante. En este artículo queremos dar una idea de estos episodios menos conocidos de la Resistenza partigiana y de la diatriba entre diferentes visiones de la misma. The Resistance is, without doubt, a relevant moment of the Italian history of …
High Performance 3D PET Reconstruction Using Spherical Basis Functions on a Polar Grid
2011
Statistical iterative methods are a widely used method of image reconstruction in emission tomography. Traditionally, the image space is modelled as a combination of cubic voxels as a matter of simplicity. After reconstruction, images are routinely filtered to reduce statistical noise at the cost of spatial resolution degradation. An alternative to produce lower noise during reconstruction is to model the image space with spherical basis functions. These basis functions overlap in space producing a significantly large number of non-zero elements in the system response matrix (SRM) to store, which additionally leads to long reconstruction times. These two problems are partly overcome by expl…