<p><strong>Abstract.</strong> The use of virtual reality and ICT in the museum context provides a new key to understand and promote Cultural Heritage: thanks to these technologies the user has the opportunity to experience without the need to come into contact with the real objects. For the museum institutions VR and ICT are a valuable tool that allows them to perform different cultural tasks, addressing the public in a much more effective way than has previously been possible. Especially through VR, it is possible to reconstruct the original context of the artworks through the interconnection of contents: the virtual visitor, while viewing the artwork, can consult useful contents for the learning process. Another revolutionary element introduced by the new technologies is linked to the possibility of creating virtual exhibitions through which it is possible to exhibit works that are not accessible or not visible. These reflections and these theoretical principles were the basis for the development of the project proposal presented in these pages, that was born as a collaboration between the R³D Lab of the Museo della Rappresentazione of University of Catania and the CIMS Lab of Carleton University, Ottawa. It consists in the creation of a virtual museum, the Timeless Museum, in order to create an educational experience, able to make the users reflect on topics such as the value of history, the sense of beauty, the relationship with our past and our future, the protection and transmission to future generations of the artistic heritage we have.</p>

<p><strong>Abstract.</strong> The aim of this paper is to demonstrate the power of the new digitization technologies and, in particular, of Virtual Reality (VR) to document and communicate the knowledge of Cultural Heritage (CH) and to shorten the distance between man and his history, enhancing architectural monuments or art masterpieces (even when they are somehow inaccessible), allowing original educational storytelling and producing innovative ways to learn and enjoy culture. The ultimate goal of this research is the virtual and interactive reconstruction of an important historical site, characterized by a great beauty as well as by a high artistic value: the complex of Santa Maria delle Grazie, in Milan. In order to test an effective digitization workflow, the experimentation focused on the areas of the convent that are closer to the church and that have been characterized by a troubled history: The Cloister of the Frogs, the Cloister of the Prior, the Old Sacristy, the Small Sacristy and the New Sacristy. These environments have been surveyed by combining photogrammetry and terrestrial laser scanning; then they have been modelled as NURBS or reconstructed in the form of meshes. In the end, the entire 3D model was imported in a game engine in order to create a realistic VR simulation, able to revive the convent’s history in a way that no written document could better explain.</p>

<p class="VARAbstract">Can we preserve cultural heritage and, consequently, the memory of the past? To answer this question, one should look at the digital revolution that the world has gone through in recent decades and analyse the complex and the dialectical relationship between cultural heritage and new technologies. Thanks to these, increasingly accurate reconstructions of archaeological sites and historical monuments are possible. The resulting digital replicas are fundamental to experience and understand cultural heritage in innovative ways: they have complex and dynamic relationships with the original objects. This research paper highlights the importance and the scientific validity of digital replicas aimed at understanding, enhancing and protecting cultural heritage. The study focuses on the virtual reconstruction of the constructive phases, from the mid-15^th century to date, of one of the most emblematic Gothic-Renaissance buildings in the city of Milan (Italy): the convent of Santa Maria delle Grazie, famous worldwide for hosting Leonardo da Vinci's Last Supper painting. This site proved to be an ideal case study because of its troubled and little-known history that led to numerous changes over the centuries. Thanks to a methodological approach based on the analysis of the documentary sources and three-dimensional (3D) modelling, it was possible to outline the chronological succession of the convent transformations; the way in which these overlapped the pre-existing structures was described starting from the Renaissance harmonious and organic interventions, to finally reach 18^th-19^thcenturies inhomogeneous and incompatible additions. Finally, the research was completed by mapping the 3D models based on the sources used and their different levels of accuracy. The 3D models have thus become a valid tool for checking and verifying the reconstruction hypotheses.</p><p class="VARAbstract">Highlights:</p><ul><li><p>The study focused on the virtual reconstruction of the convent of Santa Maria delle Grazie, one of the most emblematicGothic-Renaissance buildings in the city of Milan.</p></li><li><p>By combining data from documentary sources, architectural treatises, period photos and digital survey, the mainbuilding phases of the convent, from the 15th century to date, were digitally reconstructed.</p></li><li><p>The 3D models are enriched with information about the accuracy of the digital reconstruction, creating 3D databasesthat can be easily consulted and updated.</p></li></ul>

We study the three-dimensional field distribution of a focused axially symmetric flattened Gaussian beam. In particular, exact closed-form expressions for the intensity along the optical axis and at the focal plane are provided, together with a comparison between our results and those pertinent to the case of a converging spherical wave diffracted by a hard-edge circular aperture. Some hints for future investigations are also given

<p><strong>Abstract.</strong> This abstract illustrates an interdisciplinary research project which focuses on the study, conservation and enhancement, through 3D digitization and virtual fruition, of an asset of great naturalistic, historical and ethnoanthropological value: Grotta dei Pipistrelli of Pantalica Nature Reserve (Sortino, SR). The cave (located in the Calcinara necropolis) is characterized by a great beauty as well as by a high cultural relevance and a remarkable scientific importance. In 2005, it awarded the UNESCO World Heritage title for its high historic, archaeological and speleological profile. Despite the site is being studied by specialists in chiropterofauna, nowadays there is not a comprehensive and reliable documentation of the plano-altimetric morphology of the cave, able to constitute a 3D database of essential information (e.g. morphological, geological, textural and wildlife information) for current and future studies, and to preserve the memory of this fragile ecosystem. The process of 3D digitization aims to create a model of the cave that allows us to enjoy this place, to explore it and to closely understand it in order to limit the anthropic pressure caused by visitors on the real site. Consequently, it is proposed the creation of a virtual environment, as a reproduction of the real one, which can be enjoyed by all categories of users.</p>