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The inkjet printing for flexible electronics is an emerging technology that is continuously expanding in different fields, such as healthcare, sports, space science, and, in general, where the traditional rigid electronics is not adequate. In this paper, the design and test of an inkjet-printed device on a flexible substrate are presented. The device is an interdigital capacitor (IDC) fabricated by deposition of conductive ink on a 127 mum-thick polyimide (Kapton) film. First, the electrical characterization of the substrate material is presented. The obtained results are then used for the IDC design. Finally, the prototype is fabricated by means of an inkjet printer and tested in a frequency range from 1 GHz to 5 GHz.

The surface impedance of superconductors in function of intense (~10 T) static magnetic field at varying orientations with respect to the crystallographic axes is of large interest for both characterization purposes, in view of the material engineering, and from the point of view of devices to be used in fundamental physics experiments. A varying field orientation is customarily obtained with mechanically rotating magnets, whose complexity limits the attainable maximum fields to a few T. Here we propose a special proof of concept design for a measuring cell in which the magnetic field orientation is fixed, while the sample orientation can be changed through its incorporation in a rotating portion of the cell. The main design choices are thus proposed for the measuring cell: a cylindrical dielectric loaded resonator, to be used within the surface perturbation approach for the measurement of the surface impedance of flat samples with typical size 10×10 mm2. The main focus in this preliminary work is put on the sensitivity attainable on the surface resistance, i.e. the real part of the surface impedance.

The surface resistance of the internal coating of pipes is an important characteristic which could indicate zones with the corrosion or leakages. In the particular case of particle accelerators, this parameter becomes even more important for the performance. We designed a scanning cell for the monitoring of the surface resistance along the whole pipe length. We show an example of the geometry optimization of the scanning cell for the octagonal shaped beam screen. Taking into account a TE011 operating mode we determine the geometry of the cell from the point of view of sensitivity and the resonant frequency of the operation.

Applications of non-destructive testing methods such as ground penetrating radar (GPR), 3D laser scanners, accelerometer sensors and vibration detecting sensors amongst many others have been used to assess and monitor masonry arch bridge spans (brick and stone) in the past few years. This paper reports the application of high to low frequency GPR antenna systems (2000 MHz, 600 MHz and 200 MHz) and a 3D laser scanner on a historic masonry arch bridge (the Old Bridge, Aylesford - 860 years old) located in Kent, England. The position of different layers of the deck structure was established with the identification of the original stone base of the bridge and location of a number of structural ties (anchors – remedial work carried out previously). Results of the 3D laser scan of the bridge were crucial to initiate long-term monitoring of the structure.

In this study, a demonstration of the ground penetrating radar (GPR) potential in the health monitoring of a matured tree has been given. The main objectives of the research were to provide an effective mapping of the tree roots as well as reliable simulation scenarios representing a variety of possible internal defects in terms of shape and formation. To these purposes, the soil around a 70-year-old fir tree, with a trunk circumference of 3.40 m and an average radius of 0.55 m, was investigated. A ground-coupled multi-frequency GPR system equipped with 600 MHz and 1600 MHz central frequency antennas was used for testing purposes. In addition to the above objective, finite-difference time-domain (FDTD) simulations of the electromagnetic field propagation through the cross-section of a trunk (consistent with the investigated fir tree) were carried out. A variety of defects representing cavities created due to decay were also simulated. The results from the simulations proved significant potential for the interpretation of complex decay phenomena within the trunk.

The measurement and control of humidity is imperative for a variety of applications. We present our significant advances in humidity sensing with different classes of sensors, which includes colorimetric indicators, humidity-based touchless control, ultra-fast point humidity sensors, and fully distributed humidity sensors Refereed/Peer-reviewed

We present a study of the uncertainties on the measures of the surface resistance, obtainable with different measurement methods based on the use of dielectric-loaded resonators. We consider the so-called round robin rotation method versus the single measurement technique and we evaluate the respective uncertainties. This comparison is done in the case of samples with surface resistance near that of the resonant cavity walls. We establish the limits of application of the round robin technique versus those of the single measurement.

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.

The Guidance and Control system is a critical part of the design of a drone. This paper explains the study of a high accuracy attitude system for the SQUID TUG, a Tailless Underwater Glider drone. As the vehicle does not have movable surfaces, the entire manoeuvring system is geared to the buoyancy system and the centre of gravity displacement. We will examine the control system for a tailless AUV (Autonomous Underwater Vehicle) without any type of movable control surfaces embedded in the hydrodynamic flow whose actuators may require "waterways" through the hull.

This paper describes an integrated control system architecture with a high accuracy navigation system for an underwater glider. To optimize the glider performances, a centralized control system called "Glider Integrated Control System (GICS)" is provided: part of this system oversees the navigation function, based on an INS reference. Unlike an UAV system, in our case, some important inertial navigation error terms cannot be neglected due to the peculiar mission.