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This work presents a methodology for characterizing ultrasonic and LASER sensors aimed at detecting obstacles within the context of electrical inspections by multirotor Unmanned Aerial Vehicles (UAVs). A set of four ultrasonic and LASER sensor models is evaluated against eight target components, typically found in high-voltage towers. The results show that ultrasonic sensor arrays displaced 25 ∘ apart reduce the chances of problems related to crosstalk and angular uncertainty. Within the LASER sensor suite, solar exposure directly affects the detection behavior among lower power sensors. Based on the results obtained, a set of sensors capable of detecting multiple obstacles belonging to a high-voltage tower was identified. In this reasoning, it becomes possible to model sensor architectures for multirotor UAVs to detect multiple obstacles and advance in the state of the art in obstacle avoidance systems by UAVs in inspections of high-voltage towers. info:eu-repo/semantics/publishedVersion

Autonomous UAVs offer advantages in industrial, agriculture, environment inspection, and logistics applications. Sometimes the use of cooperative UAVs is important to solve specific demands or achieve productivity gain in these applications. An important technical challenge is the precise positioning between two or more UAVs in a cooperative task flight. Some techniques provide solutions, like the GNSS positioning, visual and LIDAR slam, and computer vision intelligent algorithms, but all these techniques present limitations that must be solved to work properly in specific environments. The proposal of new cooperative position methods is important to face these challenges. The present work proposes an evaluation of a visual relative positioning architecture between two small UAV multi-rotor aircraft working in a master-slave operation, based on an Augmented Reality tag tool. The simulation results obtained absolute error measurements lower than 0.2 cm mean and 0.01 standard deviation for X, Y and Z directions. Yaw measurements presented an absolute error lower than 0.5 ∘ C with a 0.02–5 ∘ C standard deviation. The real-world experiments executing autonomous flight with the slave UAV commanded by the master UAV achieved success in 8 of 10 experiment rounds, proving that the proposed architecture is a good approach to building cooperative master-slave UAV applications. The authors are grateful to the FCT - Foundation for Science and Technology, Portugal for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI - Research Centre in Digitalization and Intelligent Robotics (UIDB/05757/2020 and UIDP/05757/2020) and SusTEC (LA/P/0007/2021) info:eu-repo/semantics/publishedVersion

This research proposes positioning obstacle detection sensors by multirotor unmanned aerial vehicles (UAVs) dedicated to detailed inspections in high voltage towers. Different obstacle detection sensors are analyzed to compose a multisensory architecture in a multirotor UAV. The representation of the beam pattern of the sensors is modeled in the CoppeliaSim simulator to analyze the sensors’ coverage and detection performance in simulation. A multirotor UAV is designed to carry the same sensor architecture modeled in the simulation. The aircraft is used to perform flights over a deactivated electrical tower, aiming to evaluate the detection performance of the sensory architecture embedded in the aircraft. The results obtained in the simulation were compared with those obtained in a real scenario of electrical inspections. The proposed method achieved its goals as a mechanism to early evaluate the detection capability of different previously characterized sensor architectures used in multirotor UAV for electrical inspections. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020), SusTEC (LA/P/0007/2021), Oleachain ”Skills for sustainability and innovation in the value chain of traditional olive groves in the Northern Interior of Portugal” (Norte06-3559-FSE-000188) and Centro Federal de Educação Tecnológica Celso Suckow da Fonseca (CEFET/RJ). The project that gave rise to these results received the support of a fellowship from ”la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/DI20/11780028. info:eu-repo/semantics/publishedVersion

The tempo and mode of Homo sapiens dispersal in Eurasia and the demise of Neanderthals has sparked debate about the dynamics of Neanderthal extinction and its relationship to the arrival of H. sapiens. In Italy, the so-called ‘Transition’ from Neanderthals to H. sapiens is related to the Uluzzian technocomplex, i.e. the first archaeological evidence for modern human dispersal on the European continent. This paper illustrates the new chronology and stratigraphy of Uluzzo C, a rock shelter and Uluzzian key site located in the Uluzzo Bay in southern Italy, where excavations are ongoing, refining the cultural sequence known from previous excavations. Microstratigraphic investigation suggests that most of the deposit formed after dismantling of the vault of the rock shelter and due to wind input of loess deflated by the continental shelf. The occasional reactivation of the hydrology of the local karst system under more humid conditions further contributed to the formation of specific layers accumulating former Terra Rossa-type soil fragments. Superposed on sedimentary processes, strong bioturbation and the mobilization and recrystallization of calcite have been detected. Optically stimulated luminescence (OSL) ages from Uluzzo C Rock Shelter are congruent with previously published radiocarbon ages obtained on shell beads and tephrachronology from adjacent sites preserving the Uluzzian technocomplex such as Grotta del Cavallo, confirming the onset for the Uluzzian in the area to ca. 39.2–42.0 ka. The OSL chronology from Uluzzo C also provides a terminus post quem for the end of the Mousterian in the region, constraining the disappearance of the Neanderthals in that part of Italy to ≥46 ± 4 ka.

Mild cognitive impairment (MCI) is a state of declining cognitive abilities with conserved everyday functioning. MCI has been linked with increased risk of dementia. Several non-pharmacological interventions have been investigated in this population. Computerised cognitive training (CCT) is a cognition-oriented treatment aimed at improving cognition. Most of the research on CCT has focused on the immediate or short-term effects on cognition and function of people with MCI. Thus, the aim of this review is to synthesise the current evidence on the medium- and long-term effects of CCT on people with MCI.Furthermore, this will be the first meta-analysis to be conducted with www.cogtale.com, an online repository of cognition-oriented treatment studies that automatises several steps of the evidence synthesis process.

Chemical characterization of cryptotephra is critical for temporally linking archaeological sites. Here, we describe cryptotephra investigations of two Middle–Upper Paleolithic sites from north‐west Italy, Arma Veirana and Riparo Bombrini. Cryptotephra are present as small (75 wt.%) with low FeO ( 1 and P2 is also a high silica rhyolite (>75 wt.%) but with higher FeO (2.33–2.65 wt.%). Shards at Riparo Bombrini (P3) are of the same composition as P1 shards at Arma Veirana, providing a distinct link between deposits at both sites. Geochemical characteristics suggest three possible sources for P1 and P3: eruptions from Lipari Island (56–37.7 ka) in Italy, the Acigöl volcanic field (200–20 ka) in Turkey and the Miocene Kirka‐Phrigian caldera (18 Ma) in Turkey. Eruptions from Lipari Island are the most likely source for P1,3 cryptotephra. This study highlights how cryptotephra can benefit archaeology, by providing a direct link between Arma Veirana and Riparo Bombrini as well as other deposits throughout the Mediterranean.

In the context of the development of HALO3D (High Altitude Low Orbit 3D), an edge-based Finite Element Method multidisciplinary solver for hypersonic flows, this paper presents the simulation of fl...

Because of the close relationship among soils features and their forming factors, soils and paleosols are a useful archive both to reconstruct past environmental conditions and to gather information on the morphodynamic processes affecting landscape evolution through time. The formation of complex paleosols sequences is deeply affected by the combined effect of different soil forming factors that, shaping pedogenesis, leave marks that can be interpreted and used to reconstruct the climatic and environmental history of the landscape.By integrating geopedological, geomorphological and geoarchaeological data gathered in over 20 years of research, we aimed to reconstruct the environmental Holocene history of the Mt. Cusna area (Northern Italian Apennines). We collected chemical, physical and micromorphological data of about 70 soil profiles into a georeferenced database, which maps different soil characteristics from both modern soils and paleosols. The integration of soil data with other types of available data, as geomorphological map, previous paleoenvironmental and geoarcheological reconstructions, allowed to highlight natural and anthropogenic trends and model the dynamics of past climate history, past environmental conditions, and the reciprocal distribution of landforms and paleosurfaces.We have defined the occurrence of different phases of biostasy, characterized by the absence of erosion and/or deposition on the slope, the presence of vegetation cover, and the soil development, alternated with phases of rhexistasy, characterized by slope instability and soil erosion and burial. The soil and paleosols variability across the study area mirrors the different impact of soil forming factors on pedogenesis (e.g., vegetation cover, human impact, slope dynamics), supporting a detailed characterization of the succession of different environments conditions through space and time.These results highlight how soils can represent an important archive for paleoenvironmental information as well as geomorphological dynamics and demonstrate that a multi-disciplinary approach is necessary to properly characterize soils and retrace environmental changes.

In the present paper, we present the main results of a diagnostic investigation on different paintings by Mattia Preti, belonging to the Cycle of the New Church of Sarria, located inside the Church of the Immaculate Conception of Sarria (Floriana) in Malta. The analysis was carried out on the occasion of the restoration process and, due to the short time available, only on some representative areas of each painting. A multi-technique approach was applied in situ, employing X-ray fluorescence spectroscopy (XRF) and Raman microscopy. The aim was to achieve information on the execution technique, in a completely non-invasive way, following the requirements of the restorers., peer-reviewed

The interaction of human dispersal patterns with landscape features can in many cases provide useful information on the sustenance strategies of past communities. Mapping the present landscape is a necessary step in recognizing the nature, impact, and diffusion of the processes which drive the behaviour of past populations and modify palaeolandscapes. We constructed a map of the land units in the southwestern corner of Sardinia and compared them with the distribution of known Bronze Age megalithic towers called nuraghes. The vast majority of nuraghes are near the plains or at mid elevations close to the river network, in areas with the highest landscape diversity. The occurrence of nuraghes also seems to be related to elevated outcrops giving the advantage of a raised position and stable foundations. Denudation processes, Late Holocene sea level rise, and anthropogenic disturbance seem to be the most important factors driving changes in the palaeolandscape.

The paper presents an edge-based finite element method formulation for the coupled magnetohydrodynamic equations used for the simulation of magnetogasdynamic propulsion systems. The flow is modeled...