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Shoreline localization is fundamental for designing and planning shore protection works as well as for managing and monitoring various anthropic activities along the coast. The sea-land boundary, however, changes continually with time because of waves and tides, which makes the shoreline detection complex and dubious and the boundary line finally assumed can only be conventional. In the last few decades the use of several geomorphologic indicators has been proposed, such as the berm above sea level, the groundwater exit point, historic high tide levels, etc., but the aim has not been achieved yet. Among the methods used, analysis of aerial and satellite imagery is common, in particular when historic evolution of the coast has to be reconstructed. However, the land-sea boundary obtained by images is just one of the countless instantaneous boundaries, which is determined by the particular position of the sea surface and beach geomorphology at the time when images are taken. In this paper a multidisciplinary method is used to estimate the uncertainties caused by wave motion and tides on the shoreline position assessed by aerial or satellite imagery. The method is applied to a beach of the Mediterranean Sea in geomorphologic equilibrium, on the west coast of Sicily. The method explicitly takes into account various physical aspects of the coastal stretch studied and can be adopted for other analogous beaches.

L’articolo riporta e analizza i risultati del censimento dell’offerta formativa nel settore della Geomatica promosso nel 2011 dall’AUTeC. I dati vengono confrontati con quelli relativi al censimento del 2009; il confronto conferma la tendenza alla riduzione dell’offerta, in relazione soprattutto all’applicazione del nuovo ordinamento didattico e alla contrazione del numero dei docenti negli ultimi anni. Vengono presentate in conclusione alcune proposte per trovare spazi adeguati alla attività formativa del nostro settore.

L’articolo riporta i primi risultati di uno studio finalizzato al monitoraggio delle deformazioni della cupola del Teatro Massimo di Palermo provocate dalle dilatazioni termiche, con l’impiego di tecniche topografiche e fotogrammetriche integrate. In particolare, sono state utilizzate due stazioni totali robotizzate e sistemi di fotogrammetria digitale di elevata precisione. Per correlare gli spostamenti dei carrelli sui quali poggia la struttura in acciaio della cupola con i gradienti termici, sono state acquisite immagini termiche diversificate. L’obiettivo principale del lavoro consisteva nel confronto delle due tecniche di rilievo in relazione a misure di deformazione di entità molto ridotta (sub-millimetrica). I risultati ottenuti dimostrano che i carrelli funzionano ancora correttamente. Infatti, per un gradiente termico di 6°C misurato dalla termo camera, entrambe le tecniche topografiche e fotogrammetriche hanno evidenziato spostamenti dell’ordine di 0.8 mm, in accordo con le previsioni del modello deformativo teorico.

The diffusion of the use of Geographical Information Systems in archaeology has considerably increased in recent years. This multiplicity of applications is due mainly to the growing interest of archaeologists in modern methodologies for the management of archaeological data, surveyed by topographic, photogrammetric and remote sensing techniques. GIS have become a fundamental tool for managing, sharing, analyzing and visualizing spatially referenced data and they are completely substituting the traditional techniques used by archaeologists, based upon filling out forms, graphics and other paper documents. Besides in the modern global society, dominated by mass media such as Internet, the issue of utilization has become more and more important, and most of the more recent GIS applications (Multimedia GIS, WebGIS) take this aspect into consideration.

L’articolo riporta i primi risultati di uno studio finalizzato al monitoraggio delle deformazioni della cupola del Teatro Massimo di Palermo provocate dalle dilatazioni termiche, con l’impiego di tecniche topografiche e fotogrammetriche integrate. In particolare, sono state utilizzate due stazioni totali robotizzate e sistemi di fotogrammetria digitale di elevata precisione. Per correlare gli spostamenti dei carrelli sui quali poggia la struttura in acciaio della cupola con i gradienti termici, sono state acquisite immagini termiche diversificate. L’obiettivo principale del lavoro consisteva nel confronto delle due tecniche di rilievo in relazione a misure di deformazione di entità molto ridotta (submillimetrica). I risultati ottenuti dimostrano che i carrelli funzionano ancora correttamente. Infatti, per un gradiente termico di 6° C misurato dalla termo camera, entrambe le tecniche topografiche e fotogrammetriche hanno evidenziato spostamenti dell’ordine di 0.8 mm, in accordo con le previsioni del modello teorico. This paper shows the first results of a study aimed at monitoring the deformations of the dome of the Massimo Theatre in Palermo caused by thermal dilatations, with the use of topographic and photogrammetric integrated techniques. Particularly, two robotic total stations and high precision digital photogrammetric systems were employed. In order to correlate the displacements of the rollers on which the steel structure of the dome rest with the thermal gradients, different thermal images were acquired. The main goal of the work was to compare the two techniques with reference to very small (sub-millimeter) deformation measurements. The obtained results show that the rollers are still working correctly. In fact, for a thermal gradient of 6 °C surveyed by thermographic camera, both topographic and photogrammetric techniques determined displacements of the order of 0.8 mm, according with the expected deformations of the theoretic model.

This paper shows the first results of a study aimed at monitoring the deformations of the dome of the Massimo Theatre in Palermo caused by thermal dilatations, with the use of topographic and photogrammetric integrated techniques. Particularly, two robotic total stations and high precision digital photogrammetric systems were employed. In order to correlate the displacements of the rollers on which the steel structure of the dome rest with the thermal gradients, different thermal images were acquired by a thermal imaging camera. The main goal of the work was to compare the two techniques with reference to very small (submillimeter) deformation measurements. The obtained results show that the rollers are still working correctly. In fact, for a thermal gradient of 6 °C both topographic and photogrammetric techniques determined displacements in the order of 0.8 mm, according with the expected deformations of the theoretical model.

Lo studio descrive le operazioni di rilevamento con tecniche topografiche, laser-scanning e fotogrammetriche, condotte a fini conoscitivi e divulgativi sul teatro antico del sito archeologico di Palazzolo Acreide (SR). Il risultato del rilievo è consistito nella realizzazione di un modello 3D foto realistico del teatro, georiferito nel sistema cartografico UTM-ED50 con l’impiego di tecniche GPS. Come ben noto, le procedure per la realizzazione di modelli di beni culturali ad alta risoluzione, contenenti dati metrici e qualitativi sullo stato di conservazione dei beni stessi, richiedono tuttavia operazioni di editing, alle volte assai onerose dal punto di vista computazionale ed operativo. In particolare, il numero enormemente elevato di punti in fase di elaborazione dei dati laser-scanning ha mostrato talune criticità, dovute alla difficile gestione sia del modello a nuvola di punti sia del modello a superficie (mesh) derivato dal primo, con l’esigenza, dunque, di procedere alla semplificazione dei dati. A tale proposito sono state testate e verificate differenti procedure di ricampionamento, decimazione e filtraggio, in modo da ottenere un prodotto facilmente gestibile per la generazione di ulteriori elaborati 2D e 3D di dettaglio, sotto forma di profili, sezioni e modelli texturizzati navigabili, utili allo studio, all’analisi e alla divulgazione scientifica, anche attraverso il web, del sito archeologico.

Un primo rilevamento del globo celeste di Mattheus Greuter è stato effettuato dallo scrivente nel 1994 con l’impiego di tecniche topografiche e fotogrammetriche tradizionali, prima delle operazioni di restauro che hanno restituito al mappamondo il suo aspetto originario. Nel mese di giugno di quest’anno è stato eseguito un secondo rilevamento con l’impiego delle tecniche più recenti (laser scanning, fotogrammetria digitale). Il confronto fra i due rilevamenti fornisce interessanti indicazioni per valutare l’evoluzione delle tecniche in questi quindici anni.

This paper sets out the research work carried out by the Unit of Palermo University within the FIRB 2003 National Programme, directed to the compilation of an archaeological base map of the Roman site at Elaiussa Sebaste. The employed methodology is based on the use of high resolution satellite imagery; particularly, a QuickBird image was used. A GPS survey was carried out in September 2008, aimed at determination of ground control points and spot heights used to georeference the image and to construct the DTM respectively. At last a digital orthophoto of the archaeological area was compiled from the acquired data.

This paper describes the procedures used to generate 3D models of the Agora and the Byzantine Basilica of the Elaiussa archaeological site. The virtual reconstructions were carried out from the excavation data of the artefacts, made available by colleagues from the Department of Historical, Archaeological and Anthropological Science of Antiquities of the Rome “La Sapienza” University. 3D modelling software was particularly suitable to the reconstruction of these artefacts of which only few traces remain. In order to obtain a more accurate representation, 3D models of architectural elements of special value were also produced, as the capitals of the Agora re-employed in the Basilica and the combined second order columns of the church. The final representation was obtained with the help of application software particularly aimed at the generation of rendered models. Finally, the transformation into a format suitable for visualization (VRML) allows the user to study the various elements of the archaeological buildings in depth, navigating and querying the model to which texts, images or other information can be linked. This way the model becomes like a 3D homepage of a hypertext.

This work is focused on procedures and methods for the production of photorealistic and geometrically correct 3D digital models. The investigation has been addressed to the wooden painted ceiling of the “Sala Magna” in the “Palazzo Steri” of Palermo. The building of the “Steri” starts in 1320 on behalf of Manfredi I Chiaramonte and continues with his heirs Manfredi II and Manfredi III, who built the second floor and provided the building with decorations. In 1601 the Holy Inquisition moved to the Steri and transformed it in a place of imprisonment and torture. The hall in the northern side of the first floor, named “Sala Magna”, was the main room of the building. The ceiling of the “Sala Magna” is made of 24 wooden beams enriched with paintings of saints, barons and tales from the Holy Bible, according to a spread habit in the sicilian culture of the time. This research work has been developed through three steps: data collection, modelling process and texture mapping. Data collection has been performed with topographic, photogrammetric and laser scanning techniques. Two different devices have been used in laser scanning survey: Mensi GS 200 and Faro LS880. A huge point cloud of 15 million points has been used to produce a triangulated surface model of the ceiling. Topographic and photogrammetric survey have been addressed to the production of rectified images of the planar faces of the wooden beams. Modelling process has been performed using planar curves, automatically extracted from the triangulated surface; a CAD model of the entire ceiling has been produced. The CAD model has finally been textured using the rectified images, in order to produce a photorealistic and geometrically correct 3D digital model. Such model can be used both for navigation and geometric inspection.

Italy is one of the country more exposed to coasts erosion: about 1200 km of coasts on about 8350 km are moved back of about 25 m in the last 50 years. Particularly Sicily have about 300 km of coasts moved back. There are various reasons of this phenomenon: natural factor (climatic or physical-oceanographic) with environmental and economic effects. The paper reviews the activity of the Dipartimento di Rappresentazione of University of Palermo in cooperation with the Regional Agency of Environmental Protection (ARPA) about the coastline evolution in Sicily. The research is carried out on selected physiographic units marked out by important erosive phenomena. The coastline trend are reconstructed by the elaboration of aerial photos and high resolution imagery. Particularly were used the aerial photos of the years 1954-55 (scale 1:33.000), 1987 (scale 1:10000) and 1997 (scale 1:20.000). Besides were used QuickBird high resolution satellite imagery of the year 2006. The aerial photos and the QuickBird imagery have been oriented with planimetric accuracy of ± 2 m. The Ground Control Points were collected by static GPS surveys. The comparison with orthophotos allowed to estimate the real coastline trend in the last 50 years.

In last years several methodologies have been developed for guided tours of cultural heritage supported by handheld computers (PocketPC). The instruments used for this purpose are pocketPC, possibly equipped with a GPS receiver, which offer contents related to the place where the visitor is at that moment. This paper concerns the design of an innovative multimedia guide running on handheld computers to support the visit of archaeological sites. To that end the performances of various mobile phones and pocketPCs, equipped with low-cost GPS, have been tested; an application software developed by the Palermo research Unit has been installed into these devices to locate in real time the position of the visitor within a site map and to provide him in automatic way multimedia information about the archaeological area.

La sperimentazione descritta in questo lavoro riguarda la prima parte di un progetto di ricerca, tuttora in corso, che vede coinvolti l’Istituto Geografico Militare e il Dipartimento di Rappresentazione dell’Università di Palermo (DIRAP), avente come tema il raffittimento della rete IGM95 in Sicilia con l’impiego delle Reti di Stazioni Permanenti GNNS. In particolare, sono illustrati i primi risultati di uno studio relativo alla progettazione della rete di raffittimento nella provincia di Trapani e alle prime verifiche sperimentali per valutare il grado di precisione ottenuto con rilievi statici e NTRK effettuati con l’impiego di alcuni punti di coordinate note.

In this paper the electromagnetic fields measured in dynamic way and static way are compared. The experimental tests are been carried out using a car, and over that a GPS antenna and a EMC receiver is been installed, equipped with a data treatment software; 6-minutes static measurements and dynamic ones is been carried out. In the selected area for the measurements (called Monte Pellegrino (PA)) there are many radio-TV antennas. The results of experimental tests are thematic charts, automatically generated, of EMC field measured in dynamic way, compared with static measurements of EMC fields. A statistic analysis of measured data in both ways (static and dynamic) has been done, and there is a good agreement between the two series of data.

In this paper the theoretic and practical points of view about the applications of the modern digital airborne sensors in the photogrammetry and remote sensing fields are described. The first part of the paper describes the theoretic matter, the second one shows the first results regarding the carried out elaborations on an image of Palermo acquired by digital airborne sensor LH System ADS40. Besides the research has examined most of sides regarding the trilinear sensor and it has highlighted the capabilities and limitations respect to the traditional analogical system and the matricial CCD sensor.

In this paper, in order to evaluate the capability of several data, acquired by different sensors, some object-oriented classification tests have been carried out. In particular, the results obtained with two RGB ortophotos, acquired with traditional methodology, have been compared with the ones obtained with two QuickBird images and with the ones obtained by ADS40 pushbroom sensor. The object classification is based on two next steps: The classification to objects is based on two next steps: the decomposition of the whole image in dimension objects bigger than the pixel, procedure called segmentation, and the next classification with Fuzzy logic. This approach provides more reliable results with respect to the classification based on the pixels as it associates homogeneous objects on the basis of the information contained both in the objects themselves and their mutual relations. At last, the results obtained in the three cases have been compared through statistical methods necessary to evaluate the quality of the produced classifications. The comparison has been carried out through the comparing of the confusion matrixes produced on the basis of some samples extracted from the origin images. The used methodology is very useful for the monitoring and identification of landscape changes; in particular, in order to individuate the changes due to the anthropic pressure, a orthophoto, produced in 1979 by traditional techniques and two QuickBird images, acquired in 2002 and 2006 respectively and relative to the very naturalistic area have been elaborated.

Wooden painted ceilings of the Mediterranean area in the middle age have their origin in the islamic culture and were then spread in the countries under the dominion of the Arabs; some of the surviving ceilings are now located in Sicily and Spain. In the historic centre of Palermo two well preserved medieval ceilings are still surviving; the first, built in the XII century, is located in the Palatine chapel; the second one, built in the XIV century covers the “Sala Magna” in the Steri of Palermo. The research, focused on the ceiling in the Steri, deals with the definition of a process for the integration of surveying techniques (photogrammetry, laser scanning), modelling processes and communication technologies for the documentation of such artefacts. The documentation of painted ceilings requires the strict integration of photographic and 3D metric data; the existing documentation is usually made of documents (drawings, photographs) that keep geometric and metric data separated from the photographic documentation of the paintings. The first stage in this work is therefore addressed to produce a digital document that combines metric and photographic data in a 3D textured model; in the second stage a vocal guide interacting with the 3D model has been developed; such guide, thought as a support to people visiting the Steri, uses a database with historic contents and symbolic interpretation of the painted scenes to answer specific questions and “take” the visitor close to the related paintings.

Le discipline topografiche hanno registrato negli ultimi anni un profondo rinnovamento grazie soprattutto allo sviluppo delle tecnologie elettroniche ed informatiche. Nuove strumentazioni e metodologie sono state prodotte, sempre più veloci, automatiche, affidabili; basti pensare alla stazione totale, al GPS, al laser a scansione, oppure alla cartografia numerica, alle tecniche fotogrammetriche digitali, a quelle GIS. Un nuovo termine è stato di recente introdotto nel linguaggio tecnico, Geomatica, proprio ad individuare il complesso delle discipline che hanno come oggetto l’acquisizione, l’elaborazione, l’analisi, la visualizzazione e la gestione di informazioni territoriali, e che includono sia quelle tradizionali (Geodesia, Topografia, Fotogrammetria, Cartografia), nella loro versione aggiornata, sia quelle di recente istituzione (Telerilevamento, Sistemi Informativi Territoriali). Come è ovvio, a questa evoluzione hanno contribuito in modo rilevante anche i tanti studiosi che con impegno e dedizione hanno svolto la loro attività scientifica e didattica all’interno delle Università e fra questi, con un ruolo non secondario, anche quelli che hanno operato presso l’Ateneo di Palermo. Le pagine che seguono raccontano appunto le vicende legate all’evoluzione delle discipline topografiche nell’Università di Palermo attraverso la storia dei docenti che si sono succeduti nell’insegnamento nel corso di poco più di un secolo, fornendo un contributo significativo alla crescita del settore.

Le tecniche di rilievo topografico sono utilizzate da sempre per il monitoraggio di superfici rocciose per ottenere indicazioni sui micromovimenti degli stessi ammassi. Le esperienze recentemente maturate in ambito geologico-applicativo hanno mostrato le potenzialità della tecnica laser scanning long range come ausilio nel rilievo delle superfici rocciose per la possibilità di acquisire un’elevata quantità di dati con rapidità, ma con il limite di una accuratezza non inferiore al centimetro. Attraverso tale tecnica si possono indagare le principali caratteristiche geomorfologiche e geometriche dell’oggetto naturale ed eventualmente quantificare le variazioni geometriche occorse nel tempo. Il modello tridimensionale del territorio ottenuto con laser scanner può essere facilmente integrato con i sistemi di disegno CAD. Scopo del seguente lavoro è l’applicazione di tecniche topografiche tradizionali ed innovative per il monitoraggio dell’ammasso roccioso situato a Mongerbino nel Comune di Bagheria (PA), denominato “Arco Azzurro”, durante la demolizione controllata di un edificio abusivo in prossimità di esso. Per far ciò è stato effettuato un rilievo con laser scanner long range al fine di generare un modello 3D dell’arco. Tale modello è stato usato, come dato di input, nella simulazione agli elementi finiti per valutare l’attuale grado di stabilità dell’ammasso. Successivamente in funzione dello stato tensionale ottenuto dal calcolo, sono stati scelti i punti da monitorare con tecniche topografiche classiche di alta precisione.

This paper proposes a study on the virtual reconstruction of temple B in Selinunte. It is the smallest of Selinunte’s temples yet, despite its size, it has been the subject of great interest and debate by scholars since its discovery in 1823. The studies carried out throughout the XIX century and the first half of the XX century provided different renderings, especially as to the organization of the elevation. The goal of this work is the virtual anastylosis of temple B, through the study of all available historical sources, the survey of fragments preserved today at the “A.Salinas” Regional Archaeology Museum in Palermo, and the survey of the finds at Selinunte’s site. The virtual reconstruction of a partly destroyed artefact is a complex operation requiring the collaboration of many human and cultural resources, as well as the use of various technologies. The work was focused on three main aspects: high accuracy in data acquisition, communication and exchange of information among the various professionals experts taking part in the project, production of ‘open’ papers, to discuss problems in data interpretation and in possible reconstruction hypotheses. This paper intends to give a contribution to favour the knowledge and exchange of information through the use of all available resources. It also intends to represent a case study for understanding all the problems relevant to the reconstruction process of a partly destroyed artefact. The work intends to be in line with the main international guidelines about the highly detailed virtual reconstruction of cultural heritage.

Le discipline topografiche hanno registrato negli ultimi anni un profondo rinnovamento grazie soprattutto allo sviluppo delle tecnologie elettroniche ed informatiche. Nuove strumentazioni e metodologie sono state prodotte, sempre più veloci, automatiche, affidabili; basti pensare alla stazione totale, al GPS, al laser a scansione, oppure alla cartografia numerica, alle tecniche fotogrammetriche digitali, a quelle GIS. Un nuovo termine è stato di recente introdotto nel linguaggio tecnico, Geomatica, proprio ad individuare il complesso delle discipline che hanno come oggetto l’acquisizione, l’elaborazione, l’analisi, la visualizzazione e la gestione di informazioni territoriali, e che includono sia quelle tradizionali (Geodesia, Topografia, Fotogrammetria, Cartografia), nella loro versione aggiornata, sia quelle di recente istituzione (Telerilevamento, Sistemi Informativi Territoriali). Come è ovvio, a questa evoluzione hanno contribuito in modo rilevante anche i tanti studiosi che con impegno e dedizione hanno svolto la loro attività scientifica e didattica all’interno delle Università e fra questi, con un ruolo non secondario, anche quelli che hanno operato presso l’Ateneo di Palermo. Le pagine che seguono raccontano appunto le vicende legate all’evoluzione delle discipline topografiche nell’Università di Palermo attraverso la storia dei docenti che si sono succeduti nell’insegnamento nel corso di un secolo, a partire dalla metà dell’800 fino alla metà del 900, fornendo un contributo significativo alla crescita del settore.

The goal of the current research is to give the definition of standards for structure of digital cartography (relating to different nominal scales and semantic content) compatible with GIS, WEB-GIS, LBS. On the grounds of the critical analysis of those systems and the running of the related software, it was defined a possible model of cartographic structure, applied to a real case. La ricerca, tuttora in corso, è orientata alla definizione di standard di strutturazione della cartografia numerica (in relazione alle diverse scale nominali e al contenuto semantico) compatibile con i GIS, WEBGIS, LBS. Sulla base delle analisi critiche di tali sistemi e del funzionamento dei relativi software è stato definito un possibile modello di strutturazione cartografica applicato ad un caso reale.

This paper describes the first results of a study, carried out within the national research program “Cofin2001”, on the potential use of high resolution satellite images for making digital orthophotos at a scale of 1:5000 and 1:10,000. Particularly, images from IKONOS II and QuickBird of four different types of areas were employed: the first area is the city of Palermo, a greatly urbanized area; the second area is the extra-urban territory near the town of Contessa Entellina in south-western Sicily; the third area is the famous tourist resort of Scopello, in the western Sicily; the last area is the Caselle Airport, a flat zone near Torino. The first three images were orthorectified by using Rational Functions Model (RFM), varying the number of the GCP and using a DEM with 10 m gridcell; the last image was orthorectified by using the Toutin model and a DEM with 40 m grid-cell.