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THz technologies make use of non-ionizing radiation. For this reason, THz radiation is non-invasive and can be used to assess condition and composites used in the aeronautical field. In this study, we will examine glass fiber composites with simulated structural and fire damage by using a 97 GHz imaging system. The aim of the study will concern the description of the experimental apparatus and the physical principle that regulates its functioning.

The increasingly widespread use of COTS components in equipment with high added value, for critical uses and for use in aggressive environments has brought a new approach to this type of components, especially from the point of view of reliability. In this study, we will examine an approach based on the "forward development"of the Arrhenius equation and in particular of the Apparent Activation Energy Eaa. As the manufacturing technology of electronic components is improving in great strides, it is also necessary to adapt our approach to Eaa which, in some ways, is linked to constructive goodness and to the refinement of production procedures. For this it is necessary to establish a series of criteria that lead to a correct choice of the parameter in order not to have estimates of the useful life of the component that are too pessimistic and therefore unrealistic, or to have durations so favourable as to be objectively unrealistic. In this paper, we will bring some examples and propose some very conservative approaches.

Our study stems from two specific requirements, namely to mount a homing system on the Unmanned Aerial Vehicle (UAV) that is light but at the same time very precise. This question is solved by moving the entire control infrastructure to the ground thanks to very small and low-power high-frequency transmission systems. As an additional advantage, we have that of unloading the vehicle from all the avionics specifically dedicated to homing. Our study concerns the revision and updating of beamriding systems based on radio interferometry.

The cartographic unification of the Italian peninsula with the Carta Topografica d’Italia used the important work done during the pre-unification period and the last years of the XIX century. After the territorial unity of 1870 (leaving aside the appendix of the unredeemed lands of the north-east annexed after the Great War), the vision of a wider space for movement and citizenship took shape. For this reason, it is important to guard the memory and safeguard of all trigonometric points, like geodetic base lines, witnessing in the country the long and hard measurement work.

This paper analyses the use of a WSN for agricultural scenario, referencing to the modality of communication between the network nodes, and proposes a modified version of Multipath Ring Routing (MPRR) to improve performances and robustness of the network on the long period. Through simulations with Castalia, some limits of the standard MPRR have been highlighted, and through the possibility to modify the algorithm itself, improvements have been made that make the modified MPRR suitable for our scenario.

Acoustic, radio frequency (RF) and optical waves systems are the technologies that are used to carry out underwater wireless communications. In scientific, military and industrial sectors, the development of robust and efficient submarine wireless communication links is of enormous interest. To achieve secure short-range wireless communications, the Underwater Optical Wireless Communication (UOWC), which uses the 450-550 nm spectral range of the electromagnetic spectrum, is a good technology. Recently, UOWC applications have been proposed for environmental monitoring, offshore exploration, and military operations. There are many review articles published on this topic. However, research in this field evolves rapidly as does existing literature. The article deals with current and potentially available UWOC technologies in the near future. It is aimed at those who want to undertake studies in this field. Obviously, this paper does not attempt to cover every single aspect of UWOC.

In this paper the idea to develop an underwater drone optimized for shallow water, inland ports and small inlets is shown. The vehicle should be simple and robust: a mathematical part is included on the vertical balance to be able to size weights and payload volumes.

Artwork counterfeiting is an historical problem, which has nowadays still ancient solution, not based on innovative technology, due to the intrinsic nature of the artworks themselves. In this paper an innovative system based on smartphone acquisition and mobile application is depicted to verify artwork authenticity based on typical craquelure patterns present in ancient painting. These patterns are unique and can be modified only via a complete and accurate artwork restoration process. This approach is based on like biometry paradigm (analogue fingerprinting) adapted to the painting pattern.

This paper is a section of several preliminary studies of the Underwater Drones Group of the Università degli Studi “Roma Tre” Science Department. We describe the architecture and features of the Medusa as "quasi-Lagrangian" AUV and its “dual use”: a simple emerging buoy or a sub glider.

The final aim of this paper is to create peculiar strategies in order to optimise the use platform for underwater scientific research that can accommodate a wide range of different payloads. The main mission profiles and the related employment strategies are optimized, according to the dedicated environment: we will examine in detail the three types of typical mission (pure drift, corrected drift and glider) finally a hybrid one (Jellyfish).

In scientific, military, and industrial sectors, the development of robust and efficient submarine wireless communication links is of enormous interest. Underwater wireless communications can be carried out through acoustic, radio frequency (RF), and optical waves. Underwater optical communication is not a new idea, but it has recently been considered because seawater exhibits a window of reduced absorption both in the visible spectrum and long-wavelength UV light (UV-A). Compared to its bandwidth limited acoustic counterpart, underwater optical wireless communications (UOWCs) can support higher data rates at low latency levels. Underwater wireless communication networks are important in ocean exploration, military tactical operations, environmental and water pollution monitoring. Anyway, given the rapid development of UOWC technology, documents are still needed showing the state of the art and the progress made by the most current research. This paper aims to examine current technologies, and those potentially available soon, for Underwater Optical Wireless Communication and to propose a new perspective using UV-A radiation.

For military divers, having a robust, secure, and undetectable wireless communication system available is a fundamental element. Wireless intercoms using acoustic waves are currently used. These systems, even if reliable, have the defect of being easily identifiable and detectable. Visible light can pass through sea water. Therefore, light can be used to develop short-range wireless communication systems. To realize secure close-range underwater wireless communication, the Underwater Optical Wireless Communication (UOWC) can be a valid alternative to acoustic wireless communication. UOWC is not a new idea, but the problem of the presence of sunlight and the possibility of using near-ultraviolet radiation (near-UV) has not been adequately addressed in the literature yet. In military applications, the possibility of using invisible optical radiation can be of great interest. In this paper, a feasibility study is carried out to demonstrate that UOWC can be performed using near-ultraviolet radiation. The proposed system can be useful for wireless voice communications between military divers as well as amateur divers.

Growing interest is now addressed to using essential oils (EOs) as antimicrobial substances, in medical, industrial, food, and many other sectors. Oregano and thyme EOs are among the most effective oils and, for this reason, they have also been investigated in the field of cultural heritage. This work reports some preliminary results of a new approach for monitoring in-situ the biocide action on biological patinas by a fast analysis based on bioluminescence. In this research, we evaluated the efficacy of a commercial biocide based on EOs, in comparison with common commercial biocides containing hazardous formulations for human health and environment.

The use of LED light sources is nowadays an attractive solution because it can easily lead to lower operating costs of artificial lighting. In the last years, the replacement of fluorescent lamps with LED tubes for lighting of workplaces have been frequently proposed. The aim of the Authors is to analyze, from techno-economic’s point of view, the fluorescent tubes replacement of a typical office building with LED tubes. Using the evaluation of the Lighting Energy Numeric Indicator has been possible to point out that the replacement of the fluorescent tubes allows a reduction in energy consumption for lighting higher than 50% with an obvious reduction in the annual operating cost. For the lamps replacement, in the case study have been estimated a simple payback time of less than 5 years. The methodological approach used by the Authors, although based on a case study, can be extended to numerous office buildings because the analyzed configurations (use and dimension of the rooms, type and features of the luminaires) can be considered significantly representative of this type of buildings. The choice of the LED sources that are suitable for the fluorescent lamps replacement must be preceded by a careful lighting analysis in order to ensure the compliance with the standards requirements.

A modified version of LEACH routing protocol has been implemented and simulated in Castalia simulator to verify if it was good to manage a WSN dedicated for necropolis. Simulation results seem to show the valence of our idea.

An important problem in industrial system, both working in low and medium power, is the possibility that some circuits have a current dispersion, with a subsequent increasing in local temperature. This situation, if not immediately corrected, can produce, in some cases, firing accidents, with a great amount of money loss and long period of out-of-order systems. Although procedures based on Infrared Thermography to analyze and find critical situations already exist, these are always based on long manual procedures and usually are used for analysis of complex industrial systems. In this paper, after a short review of the common manual thermograph investigation, an automatic system based on two infrared thermograph cameras and an image processing real time analysis is proposed. The device demonstrates the possibility to take under control some critical systems and preventing firing accident in automatic way. This solution can be easily integrated in a SCADA architecture for monitoring and alerting the supervisor about over-temperature or current dissipation cases.

Many computing techniques are used to evaluate Power Quality parameters, each showing specific advantages and disadvantages. This paper presents an improvement of Curve Fitting Algorithm (CFA) having good accuracy in the estimation of the signal’s power quality parameters.