Search results for "Gnss"
showing 8 items of 88 documents
Dam displacements monitoring by using GNSS and remote sensing techniques
Il presente lavoro mira a valutare le potenzialità delle tecniche satellitari per il monitoraggio delle dighe. In particolare, l’attenzione è stata rivolta alle dighe di terra, poichè queste rappresentano la tipologia costruttiva più diffusa ed i modelli esistenti in letteratura sono in grado di descriverne gli spostamenti solo nell’ipotesi di conoscere accuratamente tutti parametri geotecnici e strutturali che caratterizzano la composizione della diga stessa. Negli ultimi anni, è stato ampiamente dimostrato che le tecniche satellitari da remoto sono in grado di individuare con elevata accuratezza, il comportamento di grandi strutture (incluse le dighe), valutandone spostamenti e deformazio…
Geomatic applications tourban park in palermo
2015
Over the last few years topographical techniques have developed an exponential trend towards simplifying and speeding, both survey operations and analysis of data collected reaching at the same time ever higher levels of accuracy. Among the technologies that are increasingly taking the field in this context is part of the Mobile Mapping System (MMS) that, on any mobile platform, combines sensors and measurement systems designed to provide a 3D position of the platform and, at the same time, capable to acquire geographic data without the aid of control points on the ground. The study reported concerns the verification of the reliability metrics and a qualitative MMS in order to evaluate its …
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…
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…
Bathymetry time series using high spatial resolution satellite images
2020
The use of the new generation of remote sensors, such as echo sounders and Global Navigation Satellite System (GNSS) receivers with differential correction installed in a drone, allows the acquisition of high-precision data in areas of shallow water, as in the case of the channel of the Encañizadas in the Mar Menor lagoon. This high precision information is the first step to develop the methodology to monitor the bathymetry of the Mar Menor channels. The use of high spatial resolution satellite images is the solution for monitoring many hydrological changes and it is the basis of the three-dimensional (3D) numerical models used to study transport over time, environmental variability, and wa…
A software receiver adaptive phase lock loop method
2009
The aim of this paper is to introduce a new and relatively simple algorithm which is capable to tune the parameters of the loop filter in a phase lock loop, like the one that can be found in a global navigation satellite system receiver. The parameters are chosen while the system is running, in order to make the bandwidth of the filter adaptive with respect to the signal dynamic and strength. A wider bandwidth is obtained to make the filter more reactive when searching the carrier, while the bandwidth gets narrower when the system is in the tracking state, in order to cut off as much noise as possible. The algorithm is based on the observation of the estimated variance of the phase lock loo…
Fundamentals of Precision Agriculture
2023
Precision agriculture or precision farming is the targeted application of crop input according to the locally determined crop needs. Therefore, it is the geo-referenced application of crop inputs, whose rates should be those required by the crop. The most essential points of information about the topic being described are: overview; brief history of precision agriculture; theoretical basics of precision agriculture; precision agriculture cycle; geo-referenced measurement of within-field parameters; analysis and interpretation of geo-referenced data for mapping within-field parameters; spatially variable rate application of crop inputs; instruments for precision agriculture; current scenario…
Analisi di rilievi NRTK condotti con differenti reti di stazioni permanenti in Sicilia
2010
In questo studio, tuttora in corso di approfondimento e di investigazione, viene svolta un’analisi comparata sulle correzioni differenziali ottenute da reti di stazioni permanenti differenti, ma operanti sullo stesso territorio, quello siciliano. Infatti dopo la rapida diffusione delle tecnologie informatiche, in Sicilia negli ultimi anni, si è assistito ad una proliferazione di stazioni permanenti GPS, da parte di enti pubblici e società private. In particolare nel territorio regionale siciliano sono presenti ben cinque reti di stazioni con differenti ubicazioni, strumentazioni utilizzate, software di gestione e sistemi di riferimento geodetico; oltre quella gestita e coordinata dalla Faco…