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Thanks to recent technological developments in 3D surveys, computer graphics and virtual reality, new scenarios have been opened for the documentation and enhancement of ancient sculptures. When not totally preserved, sculptures can be digitally reproduced, modified and visualized to simulate their physical or virtual reconstruction in a non-invasive way for specialists or for dissemination aims. The virtual sculptural reconstruction process starts usually from the 3D survey of real fragments, and then continues by integrating missing parts with 3D modelling techniques by means of source evaluation. Along with primary data sources (reality-based model), secondary data sources (photos, drawings and 3D models of similar sculptures) can be directly used in the reconstruction process. This approach has a double advantage of making the reconstruction activities easier and less arbitrary, contributing to a decrease in the degree of uncertainty for the sculptural reconstruction work, also thanks to many iconographic comparisons to ancient copies. Moreover, virtual reconstruction can be easily visualized alongside a scalable rendering system using open-source Web3D apps and platforms, accessing information, 3D models and descriptions in order to enhance the experience of artworks. Inspecting theoretical and technical approaches, this work aims at establishing how primary and secondary data sources can be effectively used in sculptural reconstruction workflows, and how 3D outputs can be applied to implement digital sculptural heritage exploitation for museums and cultural institutions. The statues of Aesculapius and Hygeia from the sanctuary of Isis in Lilybaeum (Marsala, Italy) were chosen as a case study.

Nowadays, technical and scientific researches are focused on the use of Global Navigation Satellite System (GNSS) Continuously Operating Reference Stations (CORS) networks due to their global impact on the satellite positioning. This study aims to describe the main steps developed by the University of Palermo for the realization of the GNSS CORS network distributed in the western part of Sicily (Italy). Specifically, it focuses on data availability, preliminary studies and analyses involving the GNSS CORS network, the geodetic framework used, the coordinates and displacements time series retrieved over time and the statistical analysis with the Cumulative Distribution Function (CDF). The analyses allowed to verify the network operating service and the quality of the recorded data during the first period of testing procedure (2008 – 2012)

The ‘Archaeological Map of Lilybaeum’ is the result of the long-standing scientific cooperation in Marsala between Palermo and Hamburg Universities. This paper investigates the various methods of field research used to gather the necessary data for the archaeological map of ancient Lilybaeum. There will be a particular focus on the topographic survey and photogrammetric aerial survey by Remotely Piloted Aircraft System (RPAS) conducted in the years 2017–2019. The aim of the work is to highlight the impact of the results on already existing research hypotheses and the ways in which the resulting map enhances our knowledge of the ancient city of Lilybaeum.

[EN] In recent years, the use of three-dimensional (3D) models in cultural and archaeological heritage for documentation and dissemination purposes has increased. New geomatics technologies have significantly reduced the time spent on fieldwork surveys and data processing. The archaeological remains can be documented and reconstructed in a digital 3D environment thanks to the new 3D survey technologies. Furthermore, the products generated by modern surveying technologies can be reconstructed in a virtual environment on effective archaeological bases and hypotheses coming from a detailed 3D data analysis. However, the choice of technologies that should be used to get the best results for different archaeological remains and how to use 3D models to improve knowledge and dissemination to a wider audience are open questions. This paper deals with the use of terrestrial laser scanners and photogrammetric surveys for the virtual reconstruction of an archaeological site. In particular, the work describes the study for the 3D documentation and virtual reconstruction of the Sanctuary of Isis in Lilybaeum, the ancient city of Marsala (southern Italy). The Sanctuary of Isis is the only Roman sacred building known in this archaeological area. Based on the survey data, it has been possible to recreate the original volumes of the ancient building and rebuild the two best-preserved floors –a geometric mosaic and an opus spicatum– for a first digital reconstruction of the archaeological complex in a 3D environment., [ES] En los últimos años, el uso de los modelos tridimensionales (3D) en el patrimonio cultural y arqueológico para los propósitos de documentación y difusión están aumentando. Las nuevas tecnologías geomáticas han reducido significativamente el tiempo de trabajo de campo y procesamiento de los datos. Los restos arquitectónicos se pueden documentar y reconstruir en un entorno digital tridimensional (3D) gracias a las nuevas tecnologías de levantamiento 3D. Además, los productos generados con las tecnologías modernas de levantamiento se pueden reconstruir en entornos virtuales a partir de bases e hipótesis arqueológicas sólidas que provienen de un análisis detallado de los datos 3D. Sin embargo, la elección de las tecnologías que se deberían usar para obtener los mejores resultados en diferentes objetos y cómo los modelos 3D para mejorar el conocimiento y la divulgación a un público más amplio son cuestiones abiertas. Este artículo aborda el uso de los escáneres láser terrestre y de los levantamientos fotogramétricos para la reconstrucción virtual del Santuario de Isis en Lilybaeum, la antigua ciudad de Marsala (sur de Italia). El Santuario de Isis es el único edificio sagrado en la ciudad romana en esta área arqueológica. Sobre la base de la toma de datos, es posible recrear los volúmenes originales del edificio antiguo y reconstruir los dos suelos mejor conservados, un mosaico geométrico y un opus spicatum, para una primera reconstrucción digital del complejo arqueológico en un entorno 3D.

In the last few decades, the use of GNSS Continuously Operating Reference Station (CORS) networks allowed improving the accuracy of real-time positioning and post-processing positioning. In this way, several applications have been performed including remote sensing, agriculture, cultural heritage and geodynamics studies. The latter have been developed analysing CORS time-series and consistent data over long periods were needed to validate the results. In Italy, specifically in Sicily, two CORS networks were be used to monitor the geodynamics motions: the Istituto Nazionale di Geofisica e Vulcanologia (INGV) GNSS CORS network in the eastern part and the University of Palermo (UNIPA) GNSS CORS network in the western part. In this research, preliminary results of time series about geodynamics motions of the western part of Sicily have been presented. In particular, the time series of the UNIPA GNSS CORS network have been analyzed over time by using the static positioning, over a period of approximately 5 years. Results showed a linear trend for all CORS time series, according to literature. An innovative methodology, the static Precise Point Positioning (PPP) has been also tested, to determine the time series of one CORS and compare the results with the static solution. The comparison between the two methodologies (static and PPP) demonstrated the capabilities of PPP technique with benefits in terms of costs and time.

Archaeological documentation is a fundamental step for research and conservation planning phases. Nowadays traditional recording is always supported by geomatics technologies which offer important support to the growth of archaeological study. The integration of sensors and methodologies seems to give the best results, in terms of time, costs and accuracy of products. In particular, the combination of Terrestrial Laser Scanner (TLS) and Unmanned Aerial Vehicle (UAV) can help the documentation of complex sites and the production of 3D and 2D products for different purposes. The paper focuses on the integration of TLS and UAV methodologies to record the thermal baths of the Roman Domus in the archaeological Park of Lylibaeum (Marsala, Italy). The combination of range and image data are useful to achieve a complete 3D model and a high-resolution orthophoto of the site, in order to provide accurate and complete documentation for archaeological research and conservative project.

3D survey and modelling of Cultural Heritage allow to store a great deal of 3D data that can be managed for different purposes. 3D models can be used for documentation, restoration and knowledge of historic architectures and monuments. In this work, a 3D survey of the main portico of the Cathedral of Monreale (Palermo, Italy) was carried out. The paper presents the data acquisition process and the 3D modelling phase. The work is aimed to reconstruct a 3D model that could be used also to set up an HBIM (Heritage or Historic Building Information Modelling) of the main portico. The result of this study could be considered as a first test to implement an HBIM platform for the whole monumental complex of the Cathedral of Monreale.

Remote sensing allowed monitoring the reservoir water level by estimating its surface extension. Surface extension has been estimated using different approaches, employing both optical (Landsat 5 TM, Landsat 7 ETM+ SLC-Off, Landsat 8 OLI-TIRS and ASTER images) and Synthetic Aperture Radar (SAR) images (Cosmo SkyMed and TerraSAR-X). Images were characterized by different acquisition modes, geometric and spectral resolutions, allowing the evaluation of alternative and/or complementary techniques. For each kind of image, two techniques have been tested: The first based on an unsupervised classification and suitable to automate the process, the second based on visual matching with contour lines with the aim of fully exploiting the dataset. Their performances were evaluated by comparison with water levels measured in situ (r2 = 0.97 using the unsupervised classification, r2 = 0.95 using visual matching) demonstrating that both techniques are suitable to quantify reservoir surface extension. However ~90% of available images were analyzed using the visual matching method, and just 37 images out of 58 using the other method. The evaluation of the water level from the water surface, using both techniques, could be easily extended to un-gauged reservoirs to manage the variations of the levels during normal operation. In addition, during the period of investigation, the use of Global Navigation Satellite System (GNSS) allowed the estimation of dam displacements. The advantage of using as reference a GNSS permanent station positioned relatively far from the dam, allowed the exclusion of any interaction with the site deformations. By comparing results from both techniques, relationships between the orthogonal displacement component via GNSS, estimated water levels via remote sensing and in situ measurements were investigated. During periods of changing water level (April 2011–September 2011 and October 2011–March 2012), the moving average of displacement time series (middle section on the dam crest) shows a range of variability of ±2 mm. The dam deformation versus reservoir water level behavior differs during the reservoir emptying and filling periods indicating a hysteresis-kind loop.

In this work, a multidisciplinary experience, aimed to study the permanent deformations of the hull of a regatta sailing yacht is described. In particular, a procedure to compare two different surfaces of the hull of a small sailing yacht, designed and manufactured at the University of Palermo, has been developed. The first one represents the original CAD model while the second one has been obtained by means of a reverse engineering approach. The reverse engineering process was performed through an automatic close-range photogrammetry survey, that has allowed to obtain very accurate measures of the hull, and a 3D modelling step by the well-known 3D computer graphics software Rhinoceros. The reverse engineering model was checked through two different procedures implemented by the graphical algorithm editor Grasshopper. The first procedure has allowed to compare the photogrammetric measurements with the rebuilt surface, in order to verify if the reverse engineering process has led to reliable results. The second has been implement to measure the deviations between the original CAD model and the rebuilt surface of the hull. This procedure has given the possibility to highlight any permanent deformation of the hull due to errors during the production phase or to excessive loads during its use. The obtained results have demonstrated that the developed procedure is very efficient and able to give detailed information on the deviation values of the two compared surfaces.

The matching between reservoirs’ water edge and digital elevation model’s (DEM) contour lines allowed determining the water level at the acquisition date of satellite images. A preliminary study was conducted on the Castello dam (Magazzolo Lake), between Alessandria della Rocca and Bivona (Agrigento, south-Italy). The accuracy assessment of the technique was than evaluated from the comparison between classified and reference objects using similarity metrics about the shape, theme, edge and position, through the plugin STEP of open source software GIS. Moreover, an independent GIS technique was implemented to evaluate the water level, based on a distances’ array between existing contour lines and nodes extracted from vectorised classification images. Results have shown the potentiality of the techniques when applied on an ideal case; advantages and disadvantages when the images are characterized by clear sky, and limits when images are acquired during not ideal atmospheric conditions.

Natural rivers are characterized by continuous variations in bed topography, especially along curved reaches. High resolution topographic data are necessary to analyze the mutual interactions between the downstream flow and the cross-stream flow, which determine the distribution of the bed-shear stress along the channel. Because of the difficulty in acquiring good and accurate data in rivers, the major part of studies have been conducted in laboratory flumes. This paper reports on a laboratory study in which the automatic digital photogrammetric survey was applied to derive the high-resolution Digital Surface Model (DSM) of the bed topography in a large amplitude meandering flume. In order to assess the advantages of the procedure, the bed profiles obtained by the DSM have been compared with those obtained using a servo-controlled vertical profiler (PV09) has been operated and discussed.

This paper describes a method, which uses full-waveform terrestrial laser scanning to survey the surface of the slope below the Temple of Juno, located in the Valley of the Temples in Agrigento (Sicily, Southern Italy). The surface is characterized by the presence of large rock blocks, which have fallen down from the upper side; possible further detachments of rock blocks would cause a situation of general instability, with a very high risk to the archaeological structures in the near future. The methodology was designed to evaluate the potential of full-waveform laser scanning technology for the production of a very high resolution 3D topographic model of the slope, to be used as a support for the interpretation of geomorphological processes and for geotechnical analysis.

The paper reports an overview of some experiences carried out by some Italian research groups (Politecnico di Milano, University of Palermo, Bruno Kessler Foundation in Trento) aimed to assess the conservation‟s state of some analysed paintings and provide useful information for further diagnostic applications. The activities were accomplished in interdisciplinary teams composed of photogrammetrists, surveyors, restorers and experts of non-destructive diagnostic techniques for Cultural Heritage. Two main aspects are considered: (i) the analysis of the radiometric contents using multispectral images and (ii) the 3D surveying for geometric deformation analysis by means of photogrammetry and laser scanning.

Aerial photos, both in colour and in black and white, have always been very important tools in archaeological surveys. Sensors, called hyperspectral, were available on the market for some years: they are able to expand the research beyond the visible area of the electromagnetic spectrum as far as the thermal infrared too. The use of these sensors, at first restricted to the applications in the traditional fields of Remote Sensing (such as, for instance, Botany, Agronomy, Geology, Hydrology), was spreading, in recent years, to some sectors, such as archaeological surveys, which were unexplored before. The presence of structures and hollows in the top subsurface is likely to cause variations in humidity in the surface. These variations affect both vegetation, and some physical features of the ground such as thermal conductivity and capacity. Especially in the first hours of day, you can notice thermal anomalies due to different evaporation. The exam of these anomalies, carried out by the use of techniques of digital processing of images in the spectrum bands particularly sensitive to the abovementioned indicators, enables the photointerpreter to determine possible signs of underground structures of archaeological interest. The application of the remote sensing in archaeology allows to acquire, with rapidity, a lot of information connected to the territory; that's the reason why, together with the development of sensors, came out the necessity to take advantage from the potentialities offered by the GIS to manage, process and file the spatial dates acquired with the remote sensing techniques. In this work, in fact, the results produced with the image processing technique were implemented in a GIS and were overlaid on the historical and contemporary maps and on the DEM in order to produce, for each study area, a Prediction map of archaeological finds.

Vision metrology and computer vision can be successfully used for archaeological heritage 3D reconstruction in very high precision 3D measurement projects. Of those archaeological objects requiring very accurate measurements (Antonino Salinas Regional Archaeological Museum in Palermo (Italy) and the other is located at the Baglio Anselmi Regional Archaeological Museum in Marsala (Italy). The mosaics survey was undertaken in order to obtain a very detailed 3D model and a full-scale ortho-image (scale 1:1), which would be useful for documentation and restoration processes. The research involved an evaluation of the potential and the related issues of the photogrammetric/computer vision approach for 3D mosaic documentation, particularly regarding the issue of camera calibration.