Lorenzo Valente

Archaeological sites and artifacts are critical for understanding historical contexts, and maintaining their integrity is a vital undertaking. At the same time, ensuring their accessibility to enable direct study and exploration is essential for both researchers and the general public. To this aim, various works have explored the use of Digital Twins (DTs) for Cultural Heritage (CH) preservation and dissemination. However, the current state of the art remains fragmented and heterogeneous, with most approaches relying on ad hoc, case-specific solutions that are rarely reusable. In particular, existing research is often centered on individual digitization projects rather than on scalable frameworks that support the systematic creation and reuse of multiple DTs. Building on these considerations, this paper presents a scalable platform designed to streamline the construction and exploitation of archaeological DTs, enabling the rapid creation of case studies for both research and dissemination purposes. Specifically, we propose a no-code authoring environment that integrates 3D reconstructions of sites and artifacts with associated semantic information (e.g., annotations and points of interest), allowing users with limited technical expertise to create and manage DT-based experiences. The resulting case studies can be edited, organized, shared, and explored through both desktop and Virtual Reality interfaces. The platform positioning with respect to existing solutions has been explicitly investigated through a comparative analysis against representative state-of-the-art systems. In addition, the proposed approach has been evaluated through quantitative performance measurements, a comparative study, and two user studies targeting the Research and Dissemination modes, respectively. The platform was co-designed with curators from the Egyptian Museum in Turin, Italy, and validated through case studies based on two archaeological sites from Deir el-Medina, Egypt.

In recent years, First Responders (FRs) have faced increasing challenges in their operations, highlighting a growing need for specialized and comprehensive training. In particular, the firefighting Incident Commanders (ICs) are playing a pivotal role, providing directions to field operators and making critical decisions in emergency situations. Over time, traditional training tools in this field have evolved, reaching their pinnacle with Augmented Sand Tables (ASTs). ASTs build on Spatial Augmented Reality (SAR), a form of eXtended Reality (XR) that utilizes projections. Although ASTs enable large-scale visualization of the morphological features of the terrain, by relying solely on SAR it is not possible to fully leverage the potential of XR, which is increasingly recognized as a powerful tool for training. This work introduces a novel approach to training ICs by integrating ASTs with XR, incorporating a learning-by-doing methodology alongside an objective measurement of trainees' performance. To this end, an XR Training System (XRTS) has been developed, combining the capabilities of an AST with personal Mixed Reality (MR) devices and integrating a physically accurate, interactive fire simulator. This system was deployed within a forest firefighting IC training course. All the system components were designed based on the theoretical foundations of decision-making to effectively develop the necessary skills. The proposed approach was compared with traditional AST-based training methods for these roles, focusing on the analysis of learning outcomes, user experience, usability, and cognitive load. The study demonstrated several advantages associated with the use of the XRTS, including improvements in training effectiveness and a notable reduction in overall cognitive load.

Train load variability has been a big concern of the railway administrators, since they affect directly the durability of bridge structures. With the objective of ensuring railway bridge durability and stablishing parameters to control the regularity of track geometry and wagons, a Brazilian railway concessionary has demanded a structural assessment of two non-ballasted bridges simultaneously with wagon axle monitoring. For this purpose, a train composed with sixteen GDU and GDT gondola wagons was used, and two wagons of this train were instrumented. Each group of four wagons of the train were used to simulate a different condition, listed as follows: variation of axle loads, wheel defects and springs with low elastic reserve. Furthermore, in one of the bridges, dynamic tests were accomplished with different track geometry irregularities, one of them with track quality TQI of 5.3 and other of 3. Dynamic and quasi-static tests were accomplished. Regarding the importance of each defect, springs with low elastic reserve were the main responsible for the increase of axle load, almost half of the equivalent impact, followed by wheel defects, variations of loads and lastly the track defects. Comparing measured impact factors with values specified by current standardization for railway bridges, it is verified that measured impact is higher than the NBR7189 and AREMA values. Therefore, the simultaneous existence of simulated defects must be avoided.